Adopt more fixed size array types for struct fields

[rbdr/mobius] / hotline / transaction_handlers.go
diff --git a/hotline/transaction_handlers.go b/hotline/transaction_handlers.go

index 7f29d7385cdacb4dde07a44eb16483ab7191a789..3d7ba14ec03931cf9a1119f927ac561bd410da7e 100644 (file)
--- a/hotline/transaction_handlers.go
+++ b/hotline/transaction_handlers.go
@@ -1,12 +1,13 @@
  package hotline
  
  import (
  package hotline
  
  import (
+       "bufio"
         "bytes"
         "encoding/binary"
         "errors"
         "fmt"
         "gopkg.in/yaml.v3"
         "bytes"
         "encoding/binary"
         "errors"
         "fmt"
         "gopkg.in/yaml.v3"
-       "io/ioutil"
+       "io"
         "math/big"
         "os"
         "path"
         "math/big"
         "os"
         "path"
@@ -16,247 +17,251 @@ import (
         "time"
  )
  
         "time"
  )
  
+type HandlerFunc func(*ClientConn, *Transaction) ([]Transaction, error)
+
  type TransactionType struct {
  type TransactionType struct {
-       Handler        func(*ClientConn, *Transaction) ([]Transaction, error) // function for handling the transaction type
-       Name           string                                                 // Name of transaction as it will appear in logging
+       Handler        HandlerFunc // function for handling the transaction type
+       Name           string      // Name of transaction as it will appear in logging
         RequiredFields []requiredField
  }
  
  var TransactionHandlers = map[uint16]TransactionType{
         // Server initiated
         RequiredFields []requiredField
  }
  
  var TransactionHandlers = map[uint16]TransactionType{
         // Server initiated
-       tranChatMsg: {
-               Name: "tranChatMsg",
+       TranChatMsg: {
+               Name: "TranChatMsg",
         },
         // Server initiated
         },
         // Server initiated
-       tranNotifyChangeUser: {
-               Name: "tranNotifyChangeUser",
+       TranNotifyChangeUser: {
+               Name: "TranNotifyChangeUser",
         },
         },
-       tranError: {
-               Name: "tranError",
+       TranError: {
+               Name: "TranError",
         },
         },
-       tranShowAgreement: {
-               Name: "tranShowAgreement",
+       TranShowAgreement: {
+               Name: "TranShowAgreement",
         },
         },
-       tranUserAccess: {
-               Name: "tranUserAccess",
+       TranUserAccess: {
+               Name: "TranUserAccess",
         },
         },
-       tranNotifyDeleteUser: {
-               Name: "tranNotifyDeleteUser",
+       TranNotifyDeleteUser: {
+               Name: "TranNotifyDeleteUser",
         },
         },
-       tranAgreed: {
-               Name:    "tranAgreed",
+       TranAgreed: {
+               Name:    "TranAgreed",
                 Handler: HandleTranAgreed,
         },
                 Handler: HandleTranAgreed,
         },
-       tranChatSend: {
-               Name:    "tranChatSend",
+       TranChatSend: {
+               Name:    "TranChatSend",
                 Handler: HandleChatSend,
                 RequiredFields: []requiredField{
                         {
                 Handler: HandleChatSend,
                 RequiredFields: []requiredField{
                         {
-                               ID:     fieldData,
+                               ID:     FieldData,
                                 minLen: 0,
                         },
                 },
         },
                                 minLen: 0,
                         },
                 },
         },
-       tranDelNewsArt: {
-               Name:    "tranDelNewsArt",
+       TranDelNewsArt: {
+               Name:    "TranDelNewsArt",
                 Handler: HandleDelNewsArt,
         },
                 Handler: HandleDelNewsArt,
         },
-       tranDelNewsItem: {
-               Name:    "tranDelNewsItem",
+       TranDelNewsItem: {
+               Name:    "TranDelNewsItem",
                 Handler: HandleDelNewsItem,
         },
                 Handler: HandleDelNewsItem,
         },
-       tranDeleteFile: {
-               Name:    "tranDeleteFile",
+       TranDeleteFile: {
+               Name:    "TranDeleteFile",
                 Handler: HandleDeleteFile,
         },
                 Handler: HandleDeleteFile,
         },
-       tranDeleteUser: {
-               Name:    "tranDeleteUser",
+       TranDeleteUser: {
+               Name:    "TranDeleteUser",
                 Handler: HandleDeleteUser,
         },
                 Handler: HandleDeleteUser,
         },
-       tranDisconnectUser: {
-               Name:    "tranDisconnectUser",
+       TranDisconnectUser: {
+               Name:    "TranDisconnectUser",
                 Handler: HandleDisconnectUser,
         },
                 Handler: HandleDisconnectUser,
         },
-       tranDownloadFile: {
-               Name:    "tranDownloadFile",
+       TranDownloadFile: {
+               Name:    "TranDownloadFile",
                 Handler: HandleDownloadFile,
         },
                 Handler: HandleDownloadFile,
         },
-       tranDownloadFldr: {
-               Name:    "tranDownloadFldr",
+       TranDownloadFldr: {
+               Name:    "TranDownloadFldr",
                 Handler: HandleDownloadFolder,
         },
                 Handler: HandleDownloadFolder,
         },
-       tranGetClientInfoText: {
-               Name:    "tranGetClientInfoText",
+       TranGetClientInfoText: {
+               Name:    "TranGetClientInfoText",
                 Handler: HandleGetClientInfoText,
         },
                 Handler: HandleGetClientInfoText,
         },
-       tranGetFileInfo: {
-               Name:    "tranGetFileInfo",
+       TranGetFileInfo: {
+               Name:    "TranGetFileInfo",
                 Handler: HandleGetFileInfo,
         },
                 Handler: HandleGetFileInfo,
         },
-       tranGetFileNameList: {
-               Name:    "tranGetFileNameList",
+       TranGetFileNameList: {
+               Name:    "TranGetFileNameList",
                 Handler: HandleGetFileNameList,
         },
                 Handler: HandleGetFileNameList,
         },
-       tranGetMsgs: {
-               Name:    "tranGetMsgs",
+       TranGetMsgs: {
+               Name:    "TranGetMsgs",
                 Handler: HandleGetMsgs,
         },
                 Handler: HandleGetMsgs,
         },
-       tranGetNewsArtData: {
-               Name:    "tranGetNewsArtData",
+       TranGetNewsArtData: {
+               Name:    "TranGetNewsArtData",
                 Handler: HandleGetNewsArtData,
         },
                 Handler: HandleGetNewsArtData,
         },
-       tranGetNewsArtNameList: {
-               Name:    "tranGetNewsArtNameList",
+       TranGetNewsArtNameList: {
+               Name:    "TranGetNewsArtNameList",
                 Handler: HandleGetNewsArtNameList,
         },
                 Handler: HandleGetNewsArtNameList,
         },
-       tranGetNewsCatNameList: {
-               Name:    "tranGetNewsCatNameList",
+       TranGetNewsCatNameList: {
+               Name:    "TranGetNewsCatNameList",
                 Handler: HandleGetNewsCatNameList,
         },
                 Handler: HandleGetNewsCatNameList,
         },
-       tranGetUser: {
-               Name:    "tranGetUser",
+       TranGetUser: {
+               Name:    "TranGetUser",
                 Handler: HandleGetUser,
         },
                 Handler: HandleGetUser,
         },
-       tranGetUserNameList: {
+       TranGetUserNameList: {
                 Name:    "tranHandleGetUserNameList",
                 Handler: HandleGetUserNameList,
         },
                 Name:    "tranHandleGetUserNameList",
                 Handler: HandleGetUserNameList,
         },
-       tranInviteNewChat: {
-               Name:    "tranInviteNewChat",
+       TranInviteNewChat: {
+               Name:    "TranInviteNewChat",
                 Handler: HandleInviteNewChat,
         },
                 Handler: HandleInviteNewChat,
         },
-       tranInviteToChat: {
-               Name:    "tranInviteToChat",
+       TranInviteToChat: {
+               Name:    "TranInviteToChat",
                 Handler: HandleInviteToChat,
         },
                 Handler: HandleInviteToChat,
         },
-       tranJoinChat: {
-               Name:    "tranJoinChat",
+       TranJoinChat: {
+               Name:    "TranJoinChat",
                 Handler: HandleJoinChat,
         },
                 Handler: HandleJoinChat,
         },
-       tranKeepAlive: {
-               Name:    "tranKeepAlive",
+       TranKeepAlive: {
+               Name:    "TranKeepAlive",
                 Handler: HandleKeepAlive,
         },
                 Handler: HandleKeepAlive,
         },
-       tranLeaveChat: {
-               Name:    "tranJoinChat",
+       TranLeaveChat: {
+               Name:    "TranJoinChat",
                 Handler: HandleLeaveChat,
         },
                 Handler: HandleLeaveChat,
         },
-       tranListUsers: {
-               Name:    "tranListUsers",
+       TranListUsers: {
+               Name:    "TranListUsers",
                 Handler: HandleListUsers,
         },
                 Handler: HandleListUsers,
         },
-       tranMoveFile: {
-               Name:    "tranMoveFile",
+       TranMoveFile: {
+               Name:    "TranMoveFile",
                 Handler: HandleMoveFile,
         },
                 Handler: HandleMoveFile,
         },
-       tranNewFolder: {
-               Name:    "tranNewFolder",
+       TranNewFolder: {
+               Name:    "TranNewFolder",
                 Handler: HandleNewFolder,
         },
                 Handler: HandleNewFolder,
         },
-       tranNewNewsCat: {
-               Name:    "tranNewNewsCat",
+       TranNewNewsCat: {
+               Name:    "TranNewNewsCat",
                 Handler: HandleNewNewsCat,
         },
                 Handler: HandleNewNewsCat,
         },
-       tranNewNewsFldr: {
-               Name:    "tranNewNewsFldr",
+       TranNewNewsFldr: {
+               Name:    "TranNewNewsFldr",
                 Handler: HandleNewNewsFldr,
         },
                 Handler: HandleNewNewsFldr,
         },
-       tranNewUser: {
-               Name:    "tranNewUser",
+       TranNewUser: {
+               Name:    "TranNewUser",
                 Handler: HandleNewUser,
         },
                 Handler: HandleNewUser,
         },
-       tranUpdateUser: {
-               Name:    "tranUpdateUser",
+       TranUpdateUser: {
+               Name:    "TranUpdateUser",
                 Handler: HandleUpdateUser,
         },
                 Handler: HandleUpdateUser,
         },
-       tranOldPostNews: {
-               Name:    "tranOldPostNews",
+       TranOldPostNews: {
+               Name:    "TranOldPostNews",
                 Handler: HandleTranOldPostNews,
         },
                 Handler: HandleTranOldPostNews,
         },
-       tranPostNewsArt: {
-               Name:    "tranPostNewsArt",
+       TranPostNewsArt: {
+               Name:    "TranPostNewsArt",
                 Handler: HandlePostNewsArt,
         },
                 Handler: HandlePostNewsArt,
         },
-       tranRejectChatInvite: {
-               Name:    "tranRejectChatInvite",
+       TranRejectChatInvite: {
+               Name:    "TranRejectChatInvite",
                 Handler: HandleRejectChatInvite,
         },
                 Handler: HandleRejectChatInvite,
         },
-       tranSendInstantMsg: {
-               Name:    "tranSendInstantMsg",
+       TranSendInstantMsg: {
+               Name:    "TranSendInstantMsg",
                 Handler: HandleSendInstantMsg,
                 RequiredFields: []requiredField{
                         {
                 Handler: HandleSendInstantMsg,
                 RequiredFields: []requiredField{
                         {
-                               ID:     fieldData,
+                               ID:     FieldData,
                                 minLen: 0,
                         },
                         {
                                 minLen: 0,
                         },
                         {
-                               ID: fieldUserID,
+                               ID: FieldUserID,
                         },
                 },
         },
                         },
                 },
         },
-       tranSetChatSubject: {
-               Name:    "tranSetChatSubject",
+       TranSetChatSubject: {
+               Name:    "TranSetChatSubject",
                 Handler: HandleSetChatSubject,
         },
                 Handler: HandleSetChatSubject,
         },
-       tranMakeFileAlias: {
-               Name:    "tranMakeFileAlias",
+       TranMakeFileAlias: {
+               Name:    "TranMakeFileAlias",
                 Handler: HandleMakeAlias,
                 RequiredFields: []requiredField{
                 Handler: HandleMakeAlias,
                 RequiredFields: []requiredField{
-                       {ID: fieldFileName, minLen: 1},
-                       {ID: fieldFilePath, minLen: 1},
-                       {ID: fieldFileNewPath, minLen: 1},
+                       {ID: FieldFileName, minLen: 1},
+                       {ID: FieldFilePath, minLen: 1},
+                       {ID: FieldFileNewPath, minLen: 1},
                 },
         },
                 },
         },
-       tranSetClientUserInfo: {
-               Name:    "tranSetClientUserInfo",
+       TranSetClientUserInfo: {
+               Name:    "TranSetClientUserInfo",
                 Handler: HandleSetClientUserInfo,
         },
                 Handler: HandleSetClientUserInfo,
         },
-       tranSetFileInfo: {
-               Name:    "tranSetFileInfo",
+       TranSetFileInfo: {
+               Name:    "TranSetFileInfo",
                 Handler: HandleSetFileInfo,
         },
                 Handler: HandleSetFileInfo,
         },
-       tranSetUser: {
-               Name:    "tranSetUser",
+       TranSetUser: {
+               Name:    "TranSetUser",
                 Handler: HandleSetUser,
         },
                 Handler: HandleSetUser,
         },
-       tranUploadFile: {
-               Name:    "tranUploadFile",
+       TranUploadFile: {
+               Name:    "TranUploadFile",
                 Handler: HandleUploadFile,
         },
                 Handler: HandleUploadFile,
         },
-       tranUploadFldr: {
-               Name:    "tranUploadFldr",
+       TranUploadFldr: {
+               Name:    "TranUploadFldr",
                 Handler: HandleUploadFolder,
         },
                 Handler: HandleUploadFolder,
         },
-       tranUserBroadcast: {
-               Name:    "tranUserBroadcast",
+       TranUserBroadcast: {
+               Name:    "TranUserBroadcast",
                 Handler: HandleUserBroadcast,
         },
                 Handler: HandleUserBroadcast,
         },
-       tranDownloadBanner: {
-               Name:    "tranDownloadBanner",
+       TranDownloadBanner: {
+               Name:    "TranDownloadBanner",
                 Handler: HandleDownloadBanner,
         },
  }
  
  func HandleChatSend(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
                 Handler: HandleDownloadBanner,
         },
  }
  
  func HandleChatSend(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessSendChat) {
+       if !cc.Authorize(accessSendChat) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to participate in chat."))
                 return res, err
         }
  
         // Truncate long usernames
         trunc := fmt.Sprintf("%13s", cc.UserName)
                 res = append(res, cc.NewErrReply(t, "You are not allowed to participate in chat."))
                 return res, err
         }
  
         // Truncate long usernames
         trunc := fmt.Sprintf("%13s", cc.UserName)
-       formattedMsg := fmt.Sprintf("\r%.14s:  %s", trunc, t.GetField(fieldData).Data)
+       formattedMsg := fmt.Sprintf("\r%.14s:  %s", trunc, t.GetField(FieldData).Data)
  
         // By holding the option key, Hotline chat allows users to send /me formatted messages like:
         // *** Halcyon does stuff
  
         // By holding the option key, Hotline chat allows users to send /me formatted messages like:
         // *** Halcyon does stuff
-       // This is indicated by the presence of the optional field fieldChatOptions in the transaction payload
-       if t.GetField(fieldChatOptions).Data != nil {
-               formattedMsg = fmt.Sprintf("\r*** %s %s", cc.UserName, t.GetField(fieldData).Data)
+       // This is indicated by the presence of the optional field FieldChatOptions set to a value of 1.
+       // Most clients do not send this option for normal chat messages.
+       if t.GetField(FieldChatOptions).Data != nil && bytes.Equal(t.GetField(FieldChatOptions).Data, []byte{0, 1}) {
+               formattedMsg = fmt.Sprintf("\r*** %s %s", cc.UserName, t.GetField(FieldData).Data)
         }
  
         }
  
-       chatID := t.GetField(fieldChatID).Data
-       // a non-nil chatID indicates the message belongs to a private chat
-       if chatID != nil {
+       // The ChatID field is used to identify messages as belonging to a private chat.
+       // All clients *except* Frogblast omit this field for public chat, but Frogblast sends a value of 00 00 00 00.
+       chatID := t.GetField(FieldChatID).Data
+       if chatID != nil && !bytes.Equal([]byte{0, 0, 0, 0}, chatID) {
                 chatInt := binary.BigEndian.Uint32(chatID)
                 privChat := cc.Server.PrivateChats[chatInt]
  
                 chatInt := binary.BigEndian.Uint32(chatID)
                 privChat := cc.Server.PrivateChats[chatInt]
  
@@ -265,10 +270,10 @@ func HandleChatSend(cc *ClientConn, t *Transaction) (res []Transaction, err erro
                 // send the message to all connected clients of the private chat
                 for _, c := range clients {
                         res = append(res, *NewTransaction(
                 // send the message to all connected clients of the private chat
                 for _, c := range clients {
                         res = append(res, *NewTransaction(
-                               tranChatMsg,
+                               TranChatMsg,
                                 c.ID,
                                 c.ID,
-                               NewField(fieldChatID, chatID),
-                               NewField(fieldData, []byte(formattedMsg)),
+                               NewField(FieldChatID, chatID),
+                               NewField(FieldData, []byte(formattedMsg)),
                         ))
                 }
                 return res, err
                         ))
                 }
                 return res, err
@@ -276,8 +281,8 @@ func HandleChatSend(cc *ClientConn, t *Transaction) (res []Transaction, err erro
  
         for _, c := range sortedClients(cc.Server.Clients) {
                 // Filter out clients that do not have the read chat permission
  
         for _, c := range sortedClients(cc.Server.Clients) {
                 // Filter out clients that do not have the read chat permission
-               if authorize(c.Account.Access, accessReadChat) {
-                       res = append(res, *NewTransaction(tranChatMsg, c.ID, NewField(fieldData, []byte(formattedMsg))))
+               if c.Authorize(accessReadChat) {
+                       res = append(res, *NewTransaction(TranChatMsg, c.ID, NewField(FieldData, []byte(formattedMsg))))
                 }
         }
  
                 }
         }
  
@@ -286,6 +291,7 @@ func HandleChatSend(cc *ClientConn, t *Transaction) (res []Transaction, err erro
  
  // HandleSendInstantMsg sends instant message to the user on the current server.
  // Fields used in the request:
  
  // HandleSendInstantMsg sends instant message to the user on the current server.
  // Fields used in the request:
+//
  //     103     User ID
  //     113     Options
  //             One of the following values:
  //     103     User ID
  //     113     Options
  //             One of the following values:
@@ -299,42 +305,65 @@ func HandleChatSend(cc *ClientConn, t *Transaction) (res []Transaction, err erro
  // Fields used in the reply:
  // None
  func HandleSendInstantMsg(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // Fields used in the reply:
  // None
  func HandleSendInstantMsg(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       msg := t.GetField(fieldData)
-       ID := t.GetField(fieldUserID)
+       if !cc.Authorize(accessSendPrivMsg) {
+               res = append(res, cc.NewErrReply(t, "You are not allowed to send private messages."))
+               return res, errors.New("user is not allowed to send private messages")
+       }
+
+       msg := t.GetField(FieldData)
+       ID := t.GetField(FieldUserID)
  
         reply := NewTransaction(
  
         reply := NewTransaction(
-               tranServerMsg,
+               TranServerMsg,
                 &ID.Data,
                 &ID.Data,
-               NewField(fieldData, msg.Data),
-               NewField(fieldUserName, cc.UserName),
-               NewField(fieldUserID, *cc.ID),
-               NewField(fieldOptions, []byte{0, 1}),
+               NewField(FieldData, msg.Data),
+               NewField(FieldUserName, cc.UserName),
+               NewField(FieldUserID, *cc.ID),
+               NewField(FieldOptions, []byte{0, 1}),
         )
  
         )
  
-       // Later versions of Hotline include the original message in the fieldQuotingMsg field so
+       // Later versions of Hotline include the original message in the FieldQuotingMsg field so
         //  the receiving client can display both the received message and what it is in reply to
         //  the receiving client can display both the received message and what it is in reply to
-       if t.GetField(fieldQuotingMsg).Data != nil {
-               reply.Fields = append(reply.Fields, NewField(fieldQuotingMsg, t.GetField(fieldQuotingMsg).Data))
+       if t.GetField(FieldQuotingMsg).Data != nil {
+               reply.Fields = append(reply.Fields, NewField(FieldQuotingMsg, t.GetField(FieldQuotingMsg).Data))
         }
  
         }
  
-       res = append(res, *reply)
-
-       id, _ := byteToInt(ID.Data)
+       id, err := byteToInt(ID.Data)
+       if err != nil {
+               return res, errors.New("invalid client ID")
+       }
         otherClient, ok := cc.Server.Clients[uint16(id)]
         if !ok {
                 return res, errors.New("invalid client ID")
         }
  
         otherClient, ok := cc.Server.Clients[uint16(id)]
         if !ok {
                 return res, errors.New("invalid client ID")
         }
  
+       // Check if target user has "Refuse private messages" flag
+       flagBitmap := big.NewInt(int64(binary.BigEndian.Uint16(otherClient.Flags)))
+       if flagBitmap.Bit(UserFlagRefusePM) == 1 {
+               res = append(res,
+                       *NewTransaction(
+                               TranServerMsg,
+                               cc.ID,
+                               NewField(FieldData, []byte(string(otherClient.UserName)+" does not accept private messages.")),
+                               NewField(FieldUserName, otherClient.UserName),
+                               NewField(FieldUserID, *otherClient.ID),
+                               NewField(FieldOptions, []byte{0, 2}),
+                       ),
+               )
+       } else {
+               res = append(res, *reply)
+       }
+
         // Respond with auto reply if other client has it enabled
         if len(otherClient.AutoReply) > 0 {
                 res = append(res,
                         *NewTransaction(
         // Respond with auto reply if other client has it enabled
         if len(otherClient.AutoReply) > 0 {
                 res = append(res,
                         *NewTransaction(
-                               tranServerMsg,
+                               TranServerMsg,
                                 cc.ID,
                                 cc.ID,
-                               NewField(fieldData, otherClient.AutoReply),
-                               NewField(fieldUserName, otherClient.UserName),
-                               NewField(fieldUserID, *otherClient.ID),
-                               NewField(fieldOptions, []byte{0, 1}),
+                               NewField(FieldData, otherClient.AutoReply),
+                               NewField(FieldUserName, otherClient.UserName),
+                               NewField(FieldUserID, *otherClient.ID),
+                               NewField(FieldOptions, []byte{0, 1}),
                         ),
                 )
         }
                         ),
                 )
         }
@@ -344,9 +373,11 @@ func HandleSendInstantMsg(cc *ClientConn, t *Transaction) (res []Transaction, er
         return res, err
  }
  
         return res, err
  }
  
+var fileTypeFLDR = [4]byte{0x66, 0x6c, 0x64, 0x72}
+
  func HandleGetFileInfo(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  func HandleGetFileInfo(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       fileName := t.GetField(fieldFileName).Data
-       filePath := t.GetField(fieldFilePath).Data
+       fileName := t.GetField(FieldFileName).Data
+       filePath := t.GetField(FieldFilePath).Data
  
         fullFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, fileName)
         if err != nil {
  
         fullFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, fileName)
         if err != nil {
@@ -358,29 +389,44 @@ func HandleGetFileInfo(cc *ClientConn, t *Transaction) (res []Transaction, err e
                 return res, err
         }
  
                 return res, err
         }
  
-       res = append(res, cc.NewReply(t,
-               NewField(fieldFileName, []byte(fw.name)),
-               NewField(fieldFileTypeString, fw.ffo.FlatFileInformationFork.friendlyType()),
-               NewField(fieldFileCreatorString, fw.ffo.FlatFileInformationFork.friendlyCreator()),
-               NewField(fieldFileComment, fw.ffo.FlatFileInformationFork.Comment),
-               NewField(fieldFileType, fw.ffo.FlatFileInformationFork.TypeSignature),
-               NewField(fieldFileCreateDate, fw.ffo.FlatFileInformationFork.CreateDate),
-               NewField(fieldFileModifyDate, fw.ffo.FlatFileInformationFork.ModifyDate),
-               NewField(fieldFileSize, fw.totalSize()),
-       ))
+       encodedName, err := txtEncoder.String(fw.name)
+       if err != nil {
+               return res, fmt.Errorf("invalid filepath encoding: %w", err)
+       }
+
+       fields := []Field{
+               NewField(FieldFileName, []byte(encodedName)),
+               NewField(FieldFileTypeString, fw.ffo.FlatFileInformationFork.friendlyType()),
+               NewField(FieldFileCreatorString, fw.ffo.FlatFileInformationFork.friendlyCreator()),
+               NewField(FieldFileType, fw.ffo.FlatFileInformationFork.TypeSignature[:]),
+               NewField(FieldFileCreateDate, fw.ffo.FlatFileInformationFork.CreateDate[:]),
+               NewField(FieldFileModifyDate, fw.ffo.FlatFileInformationFork.ModifyDate[:]),
+       }
+
+       // Include the optional FileComment field if there is a comment.
+       if len(fw.ffo.FlatFileInformationFork.Comment) != 0 {
+               fields = append(fields, NewField(FieldFileComment, fw.ffo.FlatFileInformationFork.Comment))
+       }
+
+       // Include the FileSize field for files.
+       if fw.ffo.FlatFileInformationFork.TypeSignature != fileTypeFLDR {
+               fields = append(fields, NewField(FieldFileSize, fw.totalSize()))
+       }
+
+       res = append(res, cc.NewReply(t, fields...))
         return res, err
  }
  
         return res, err
  }
  
-// HandleSetFileInfo updates a file or folder name and/or comment from the Get Info window
+// HandleSetFileInfo updates a file or folder Name and/or comment from the Get Info window
  // Fields used in the request:
  // Fields used in the request:
-// * 201       File name
+// * 201       File Name
  // * 202       File path       Optional
  // * 202       File path       Optional
-// * 211       File new name   Optional
+// * 211       File new Name   Optional
  // * 210       File comment    Optional
  // Fields used in the reply:   None
  func HandleSetFileInfo(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // * 210       File comment    Optional
  // Fields used in the reply:   None
  func HandleSetFileInfo(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       fileName := t.GetField(fieldFileName).Data
-       filePath := t.GetField(fieldFilePath).Data
+       fileName := t.GetField(FieldFileName).Data
+       filePath := t.GetField(FieldFilePath).Data
  
         fullFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, fileName)
         if err != nil {
  
         fullFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, fileName)
         if err != nil {
@@ -396,44 +442,44 @@ func HandleSetFileInfo(cc *ClientConn, t *Transaction) (res []Transaction, err e
         if err != nil {
                 return res, err
         }
         if err != nil {
                 return res, err
         }
-       if t.GetField(fieldFileComment).Data != nil {
+       if t.GetField(FieldFileComment).Data != nil {
                 switch mode := fi.Mode(); {
                 case mode.IsDir():
                 switch mode := fi.Mode(); {
                 case mode.IsDir():
-                       if !authorize(cc.Account.Access, accessSetFolderComment) {
+                       if !cc.Authorize(accessSetFolderComment) {
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to set comments for folders."))
                                 return res, err
                         }
                 case mode.IsRegular():
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to set comments for folders."))
                                 return res, err
                         }
                 case mode.IsRegular():
-                       if !authorize(cc.Account.Access, accessSetFileComment) {
+                       if !cc.Authorize(accessSetFileComment) {
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to set comments for files."))
                                 return res, err
                         }
                 }
  
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to set comments for files."))
                                 return res, err
                         }
                 }
  
-               if err := hlFile.ffo.FlatFileInformationFork.setComment(t.GetField(fieldFileComment).Data); err != nil {
+               if err := hlFile.ffo.FlatFileInformationFork.setComment(t.GetField(FieldFileComment).Data); err != nil {
                         return res, err
                 }
                 w, err := hlFile.infoForkWriter()
                 if err != nil {
                         return res, err
                 }
                         return res, err
                 }
                 w, err := hlFile.infoForkWriter()
                 if err != nil {
                         return res, err
                 }
-               _, err = w.Write(hlFile.ffo.FlatFileInformationFork.MarshalBinary())
+               _, err = io.Copy(w, &hlFile.ffo.FlatFileInformationFork)
                 if err != nil {
                         return res, err
                 }
         }
  
                 if err != nil {
                         return res, err
                 }
         }
  
-       fullNewFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, t.GetField(fieldFileNewName).Data)
+       fullNewFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, t.GetField(FieldFileNewName).Data)
         if err != nil {
                 return nil, err
         }
  
         if err != nil {
                 return nil, err
         }
  
-       fileNewName := t.GetField(fieldFileNewName).Data
+       fileNewName := t.GetField(FieldFileNewName).Data
  
         if fileNewName != nil {
                 switch mode := fi.Mode(); {
                 case mode.IsDir():
  
         if fileNewName != nil {
                 switch mode := fi.Mode(); {
                 case mode.IsDir():
-                       if !authorize(cc.Account.Access, accessRenameFolder) {
+                       if !cc.Authorize(accessRenameFolder) {
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to rename folders."))
                                 return res, err
                         }
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to rename folders."))
                                 return res, err
                         }
@@ -443,7 +489,7 @@ func HandleSetFileInfo(cc *ClientConn, t *Transaction) (res []Transaction, err e
                                 return res, err
                         }
                 case mode.IsRegular():
                                 return res, err
                         }
                 case mode.IsRegular():
-                       if !authorize(cc.Account.Access, accessRenameFile) {
+                       if !cc.Authorize(accessRenameFile) {
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to rename files."))
                                 return res, err
                         }
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to rename files."))
                                 return res, err
                         }
@@ -451,14 +497,18 @@ func HandleSetFileInfo(cc *ClientConn, t *Transaction) (res []Transaction, err e
                         if err != nil {
                                 return nil, err
                         }
                         if err != nil {
                                 return nil, err
                         }
-                       hlFile.name = string(fileNewName)
+                       hlFile.name, err = txtDecoder.String(string(fileNewName))
+                       if err != nil {
+                               return res, fmt.Errorf("invalid filepath encoding: %w", err)
+                       }
+
                         err = hlFile.move(fileDir)
                         if os.IsNotExist(err) {
                                 res = append(res, cc.NewErrReply(t, "Cannot rename file "+string(fileName)+" because it does not exist or cannot be found."))
                                 return res, err
                         }
                         if err != nil {
                         err = hlFile.move(fileDir)
                         if os.IsNotExist(err) {
                                 res = append(res, cc.NewErrReply(t, "Cannot rename file "+string(fileName)+" because it does not exist or cannot be found."))
                                 return res, err
                         }
                         if err != nil {
-                               panic(err)
+                               return res, err
                         }
                 }
         }
                         }
                 }
         }
@@ -469,12 +519,12 @@ func HandleSetFileInfo(cc *ClientConn, t *Transaction) (res []Transaction, err e
  
  // HandleDeleteFile deletes a file or folder
  // Fields used in the request:
  
  // HandleDeleteFile deletes a file or folder
  // Fields used in the request:
-// * 201       File name
+// * 201       File Name
  // * 202       File path
  // Fields used in the reply: none
  func HandleDeleteFile(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // * 202       File path
  // Fields used in the reply: none
  func HandleDeleteFile(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       fileName := t.GetField(fieldFileName).Data
-       filePath := t.GetField(fieldFilePath).Data
+       fileName := t.GetField(FieldFileName).Data
+       filePath := t.GetField(FieldFilePath).Data
  
         fullFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, fileName)
         if err != nil {
  
         fullFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, fileName)
         if err != nil {
@@ -494,12 +544,12 @@ func HandleDeleteFile(cc *ClientConn, t *Transaction) (res []Transaction, err er
  
         switch mode := fi.Mode(); {
         case mode.IsDir():
  
         switch mode := fi.Mode(); {
         case mode.IsDir():
-               if !authorize(cc.Account.Access, accessDeleteFolder) {
+               if !cc.Authorize(accessDeleteFolder) {
                         res = append(res, cc.NewErrReply(t, "You are not allowed to delete folders."))
                         return res, err
                 }
         case mode.IsRegular():
                         res = append(res, cc.NewErrReply(t, "You are not allowed to delete folders."))
                         return res, err
                 }
         case mode.IsRegular():
-               if !authorize(cc.Account.Access, accessDeleteFile) {
+               if !cc.Authorize(accessDeleteFile) {
                         res = append(res, cc.NewErrReply(t, "You are not allowed to delete files."))
                         return res, err
                 }
                         res = append(res, cc.NewErrReply(t, "You are not allowed to delete files."))
                         return res, err
                 }
@@ -515,19 +565,19 @@ func HandleDeleteFile(cc *ClientConn, t *Transaction) (res []Transaction, err er
  
  // HandleMoveFile moves files or folders. Note: seemingly not documented
  func HandleMoveFile(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  
  // HandleMoveFile moves files or folders. Note: seemingly not documented
  func HandleMoveFile(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       fileName := string(t.GetField(fieldFileName).Data)
+       fileName := string(t.GetField(FieldFileName).Data)
  
  
-       filePath, err := readPath(cc.Server.Config.FileRoot, t.GetField(fieldFilePath).Data, t.GetField(fieldFileName).Data)
+       filePath, err := readPath(cc.Server.Config.FileRoot, t.GetField(FieldFilePath).Data, t.GetField(FieldFileName).Data)
         if err != nil {
                 return res, err
         }
  
         if err != nil {
                 return res, err
         }
  
-       fileNewPath, err := readPath(cc.Server.Config.FileRoot, t.GetField(fieldFileNewPath).Data, nil)
+       fileNewPath, err := readPath(cc.Server.Config.FileRoot, t.GetField(FieldFileNewPath).Data, nil)
         if err != nil {
                 return res, err
         }
  
         if err != nil {
                 return res, err
         }
  
-       cc.logger.Infow("Move file", "src", filePath+"/"+fileName, "dst", fileNewPath+"/"+fileName)
+       cc.logger.Info("Move file", "src", filePath+"/"+fileName, "dst", fileNewPath+"/"+fileName)
  
         hlFile, err := newFileWrapper(cc.Server.FS, filePath, 0)
         if err != nil {
  
         hlFile, err := newFileWrapper(cc.Server.FS, filePath, 0)
         if err != nil {
@@ -539,17 +589,14 @@ func HandleMoveFile(cc *ClientConn, t *Transaction) (res []Transaction, err erro
                 res = append(res, cc.NewErrReply(t, "Cannot delete file "+fileName+" because it does not exist or cannot be found."))
                 return res, err
         }
                 res = append(res, cc.NewErrReply(t, "Cannot delete file "+fileName+" because it does not exist or cannot be found."))
                 return res, err
         }
-       if err != nil {
-               return res, err
-       }
         switch mode := fi.Mode(); {
         case mode.IsDir():
         switch mode := fi.Mode(); {
         case mode.IsDir():
-               if !authorize(cc.Account.Access, accessMoveFolder) {
+               if !cc.Authorize(accessMoveFolder) {
                         res = append(res, cc.NewErrReply(t, "You are not allowed to move folders."))
                         return res, err
                 }
         case mode.IsRegular():
                         res = append(res, cc.NewErrReply(t, "You are not allowed to move folders."))
                         return res, err
                 }
         case mode.IsRegular():
-               if !authorize(cc.Account.Access, accessMoveFile) {
+               if !cc.Authorize(accessMoveFile) {
                         res = append(res, cc.NewErrReply(t, "You are not allowed to move files."))
                         return res, err
                 }
                         res = append(res, cc.NewErrReply(t, "You are not allowed to move files."))
                         return res, err
                 }
@@ -564,20 +611,20 @@ func HandleMoveFile(cc *ClientConn, t *Transaction) (res []Transaction, err erro
  }
  
  func HandleNewFolder(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleNewFolder(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessCreateFolder) {
+       if !cc.Authorize(accessCreateFolder) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to create folders."))
                 return res, err
         }
                 res = append(res, cc.NewErrReply(t, "You are not allowed to create folders."))
                 return res, err
         }
-       folderName := string(t.GetField(fieldFileName).Data)
+       folderName := string(t.GetField(FieldFileName).Data)
  
         folderName = path.Join("/", folderName)
  
         var subPath string
  
  
         folderName = path.Join("/", folderName)
  
         var subPath string
  
-       // fieldFilePath is only present for nested paths
-       if t.GetField(fieldFilePath).Data != nil {
+       // FieldFilePath is only present for nested paths
+       if t.GetField(FieldFilePath).Data != nil {
                 var newFp FilePath
                 var newFp FilePath
-               err := newFp.UnmarshalBinary(t.GetField(fieldFilePath).Data)
+               _, err := newFp.Write(t.GetField(FieldFilePath).Data)
                 if err != nil {
                         return nil, err
                 }
                 if err != nil {
                         return nil, err
                 }
@@ -587,16 +634,18 @@ func HandleNewFolder(cc *ClientConn, t *Transaction) (res []Transaction, err err
                 }
         }
         newFolderPath := path.Join(cc.Server.Config.FileRoot, subPath, folderName)
                 }
         }
         newFolderPath := path.Join(cc.Server.Config.FileRoot, subPath, folderName)
+       newFolderPath, err = txtDecoder.String(newFolderPath)
+       if err != nil {
+               return res, fmt.Errorf("invalid filepath encoding: %w", err)
+       }
  
  
-       // TODO: check path and folder name lengths
+       // TODO: check path and folder Name lengths
  
         if _, err := cc.Server.FS.Stat(newFolderPath); !os.IsNotExist(err) {
  
         if _, err := cc.Server.FS.Stat(newFolderPath); !os.IsNotExist(err) {
-               msg := fmt.Sprintf("Cannot create folder \"%s\" because there is already a file or folder with that name.", folderName)
+               msg := fmt.Sprintf("Cannot create folder \"%s\" because there is already a file or folder with that Name.", folderName)
                 return []Transaction{cc.NewErrReply(t, msg)}, nil
         }
  
                 return []Transaction{cc.NewErrReply(t, msg)}, nil
         }
  
-       // TODO: check for disallowed characters to maintain compatibility for original client
-
         if err := cc.Server.FS.Mkdir(newFolderPath, 0777); err != nil {
                 msg := fmt.Sprintf("Cannot create folder \"%s\" because an error occurred.", folderName)
                 return []Transaction{cc.NewErrReply(t, msg)}, nil
         if err := cc.Server.FS.Mkdir(newFolderPath, 0777); err != nil {
                 msg := fmt.Sprintf("Cannot create folder \"%s\" because an error occurred.", folderName)
                 return []Transaction{cc.NewErrReply(t, msg)}, nil
@@ -607,34 +656,38 @@ func HandleNewFolder(cc *ClientConn, t *Transaction) (res []Transaction, err err
  }
  
  func HandleSetUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleSetUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessModifyUser) {
+       if !cc.Authorize(accessModifyUser) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to modify accounts."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to modify accounts."))
                 return res, err
         }
  
-       login := DecodeUserString(t.GetField(fieldUserLogin).Data)
-       userName := string(t.GetField(fieldUserName).Data)
+       login := string(encodeString(t.GetField(FieldUserLogin).Data))
+       userName := string(t.GetField(FieldUserName).Data)
  
  
-       newAccessLvl := t.GetField(fieldUserAccess).Data
+       newAccessLvl := t.GetField(FieldUserAccess).Data
  
         account := cc.Server.Accounts[login]
  
         account := cc.Server.Accounts[login]
-       account.Access = &newAccessLvl
+       if account == nil {
+               return append(res, cc.NewErrReply(t, "Account not found.")), nil
+       }
         account.Name = userName
         account.Name = userName
+       copy(account.Access[:], newAccessLvl)
  
         // If the password field is cleared in the Hotline edit user UI, the SetUser transaction does
  
         // If the password field is cleared in the Hotline edit user UI, the SetUser transaction does
-       // not include fieldUserPassword
-       if t.GetField(fieldUserPassword).Data == nil {
+       // not include FieldUserPassword
+       if t.GetField(FieldUserPassword).Data == nil {
                 account.Password = hashAndSalt([]byte(""))
         }
                 account.Password = hashAndSalt([]byte(""))
         }
-       if len(t.GetField(fieldUserPassword).Data) > 1 {
-               account.Password = hashAndSalt(t.GetField(fieldUserPassword).Data)
+
+       if !bytes.Equal([]byte{0}, t.GetField(FieldUserPassword).Data) {
+               account.Password = hashAndSalt(t.GetField(FieldUserPassword).Data)
         }
  
         out, err := yaml.Marshal(&account)
         if err != nil {
                 return res, err
         }
         }
  
         out, err := yaml.Marshal(&account)
         if err != nil {
                 return res, err
         }
-       if err := os.WriteFile(cc.Server.ConfigDir+"Users/"+login+".yaml", out, 0666); err != nil {
+       if err := os.WriteFile(filepath.Join(cc.Server.ConfigDir, "Users", login+".yaml"), out, 0666); err != nil {
                 return res, err
         }
  
                 return res, err
         }
  
@@ -642,25 +695,25 @@ func HandleSetUser(cc *ClientConn, t *Transaction) (res []Transaction, err error
         for _, c := range cc.Server.Clients {
                 if c.Account.Login == login {
                         // Note: comment out these two lines to test server-side deny messages
         for _, c := range cc.Server.Clients {
                 if c.Account.Login == login {
                         // Note: comment out these two lines to test server-side deny messages
-                       newT := NewTransaction(tranUserAccess, c.ID, NewField(fieldUserAccess, newAccessLvl))
+                       newT := NewTransaction(TranUserAccess, c.ID, NewField(FieldUserAccess, newAccessLvl))
                         res = append(res, *newT)
  
                         res = append(res, *newT)
  
-                       flagBitmap := big.NewInt(int64(binary.BigEndian.Uint16(*c.Flags)))
-                       if authorize(c.Account.Access, accessDisconUser) {
-                               flagBitmap.SetBit(flagBitmap, userFlagAdmin, 1)
+                       flagBitmap := big.NewInt(int64(binary.BigEndian.Uint16(c.Flags)))
+                       if c.Authorize(accessDisconUser) {
+                               flagBitmap.SetBit(flagBitmap, UserFlagAdmin, 1)
                         } else {
                         } else {
-                               flagBitmap.SetBit(flagBitmap, userFlagAdmin, 0)
+                               flagBitmap.SetBit(flagBitmap, UserFlagAdmin, 0)
                         }
                         }
-                       binary.BigEndian.PutUint16(*c.Flags, uint16(flagBitmap.Int64()))
+                       binary.BigEndian.PutUint16(c.Flags, uint16(flagBitmap.Int64()))
  
                         c.Account.Access = account.Access
  
                         cc.sendAll(
  
                         c.Account.Access = account.Access
  
                         cc.sendAll(
-                               tranNotifyChangeUser,
-                               NewField(fieldUserID, *c.ID),
-                               NewField(fieldUserFlags, *c.Flags),
-                               NewField(fieldUserName, c.UserName),
-                               NewField(fieldUserIconID, *c.Icon),
+                               TranNotifyChangeUser,
+                               NewField(FieldUserID, *c.ID),
+                               NewField(FieldUserFlags, c.Flags),
+                               NewField(FieldUserName, c.UserName),
+                               NewField(FieldUserIconID, c.Icon),
                         )
                 }
         }
                         )
                 }
         }
@@ -670,36 +723,41 @@ func HandleSetUser(cc *ClientConn, t *Transaction) (res []Transaction, err error
  }
  
  func HandleGetUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleGetUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessOpenUser) {
+       if !cc.Authorize(accessOpenUser) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to view accounts."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to view accounts."))
                 return res, err
         }
  
-       account := cc.Server.Accounts[string(t.GetField(fieldUserLogin).Data)]
+       account := cc.Server.Accounts[string(t.GetField(FieldUserLogin).Data)]
         if account == nil {
                 res = append(res, cc.NewErrReply(t, "Account does not exist."))
                 return res, err
         }
  
         res = append(res, cc.NewReply(t,
         if account == nil {
                 res = append(res, cc.NewErrReply(t, "Account does not exist."))
                 return res, err
         }
  
         res = append(res, cc.NewReply(t,
-               NewField(fieldUserName, []byte(account.Name)),
-               NewField(fieldUserLogin, negateString(t.GetField(fieldUserLogin).Data)),
-               NewField(fieldUserPassword, []byte(account.Password)),
-               NewField(fieldUserAccess, *account.Access),
+               NewField(FieldUserName, []byte(account.Name)),
+               NewField(FieldUserLogin, encodeString(t.GetField(FieldUserLogin).Data)),
+               NewField(FieldUserPassword, []byte(account.Password)),
+               NewField(FieldUserAccess, account.Access[:]),
         ))
         return res, err
  }
  
  func HandleListUsers(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
         ))
         return res, err
  }
  
  func HandleListUsers(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessOpenUser) {
+       if !cc.Authorize(accessOpenUser) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to view accounts."))
                 return res, err
         }
  
         var userFields []Field
         for _, acc := range cc.Server.Accounts {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to view accounts."))
                 return res, err
         }
  
         var userFields []Field
         for _, acc := range cc.Server.Accounts {
-               userField := acc.MarshalBinary()
-               userFields = append(userFields, NewField(fieldData, userField))
+               accCopy := *acc
+               b, err := io.ReadAll(&accCopy)
+               if err != nil {
+                       return res, err
+               }
+
+               userFields = append(userFields, NewField(FieldData, b))
         }
  
         res = append(res, cc.NewReply(t, userFields...))
         }
  
         res = append(res, cc.NewReply(t, userFields...))
@@ -717,75 +775,120 @@ func HandleListUsers(cc *ClientConn, t *Transaction) (res []Transaction, err err
  // performed.  This seems to be the only place in the Hotline protocol where a data field contains another data field.
  func HandleUpdateUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
         for _, field := range t.Fields {
  // performed.  This seems to be the only place in the Hotline protocol where a data field contains another data field.
  func HandleUpdateUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
         for _, field := range t.Fields {
-               subFields, err := ReadFields(field.Data[0:2], field.Data[2:])
-               if err != nil {
-                       return res, err
+               var subFields []Field
+
+               // Create a new scanner for parsing incoming bytes into transaction tokens
+               scanner := bufio.NewScanner(bytes.NewReader(field.Data[2:]))
+               scanner.Split(fieldScanner)
+
+               for i := 0; i < int(binary.BigEndian.Uint16(field.Data[0:2])); i++ {
+                       scanner.Scan()
+
+                       var field Field
+                       if _, err := field.Write(scanner.Bytes()); err != nil {
+                               return res, fmt.Errorf("error reading field: %w", err)
+                       }
+                       subFields = append(subFields, field)
                 }
  
                 }
  
+               // If there's only one subfield, that indicates this is a delete operation for the login in FieldData
                 if len(subFields) == 1 {
                 if len(subFields) == 1 {
-                       login := DecodeUserString(getField(fieldData, &subFields).Data)
-                       cc.logger.Infow("DeleteUser", "login", login)
-
-                       if !authorize(cc.Account.Access, accessDeleteUser) {
+                       if !cc.Authorize(accessDeleteUser) {
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to delete accounts."))
                                 return res, err
                         }
  
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to delete accounts."))
                                 return res, err
                         }
  
+                       login := string(encodeString(getField(FieldData, &subFields).Data))
+                       cc.logger.Info("DeleteUser", "login", login)
+
                         if err := cc.Server.DeleteUser(login); err != nil {
                                 return res, err
                         }
                         continue
                 }
  
                         if err := cc.Server.DeleteUser(login); err != nil {
                                 return res, err
                         }
                         continue
                 }
  
-               login := DecodeUserString(getField(fieldUserLogin, &subFields).Data)
+               // login of the account to update
+               var accountToUpdate, loginToRename string
  
  
-               // check if the login dataFile; if so, we know we are updating an existing user
-               if acc, ok := cc.Server.Accounts[login]; ok {
-                       cc.logger.Infow("UpdateUser", "login", login)
+               // If FieldData is included, this is a rename operation where FieldData contains the login of the existing
+               // account and FieldUserLogin contains the new login.
+               if getField(FieldData, &subFields) != nil {
+                       loginToRename = string(encodeString(getField(FieldData, &subFields).Data))
+               }
+               userLogin := string(encodeString(getField(FieldUserLogin, &subFields).Data))
+               if loginToRename != "" {
+                       accountToUpdate = loginToRename
+               } else {
+                       accountToUpdate = userLogin
+               }
  
  
-                       // account dataFile, so this is an update action
-                       if !authorize(cc.Account.Access, accessModifyUser) {
+               // Check if accountToUpdate has an existing account.  If so, we know we are updating an existing user.
+               if acc, ok := cc.Server.Accounts[accountToUpdate]; ok {
+                       if loginToRename != "" {
+                               cc.logger.Info("RenameUser", "prevLogin", accountToUpdate, "newLogin", userLogin)
+                       } else {
+                               cc.logger.Info("UpdateUser", "login", accountToUpdate)
+                       }
+
+                       // account exists, so this is an update action
+                       if !cc.Authorize(accessModifyUser) {
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to modify accounts."))
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to modify accounts."))
-                               return res, err
+                               return res, nil
                         }
  
                         }
  
-                       if getField(fieldUserPassword, &subFields) != nil {
-                               newPass := getField(fieldUserPassword, &subFields).Data
-                               acc.Password = hashAndSalt(newPass)
+                       // This part is a bit tricky. There are three possibilities:
+                       // 1) The transaction is intended to update the password.
+                       //        In this case, FieldUserPassword is sent with the new password.
+                       // 2) The transaction is intended to remove the password.
+                       //    In this case, FieldUserPassword is not sent.
+                       // 3) The transaction updates the users access bits, but not the password.
+                       //    In this case, FieldUserPassword is sent with zero as the only byte.
+                       if getField(FieldUserPassword, &subFields) != nil {
+                               newPass := getField(FieldUserPassword, &subFields).Data
+                               if !bytes.Equal([]byte{0}, newPass) {
+                                       acc.Password = hashAndSalt(newPass)
+                               }
                         } else {
                                 acc.Password = hashAndSalt([]byte(""))
                         }
  
                         } else {
                                 acc.Password = hashAndSalt([]byte(""))
                         }
  
-                       if getField(fieldUserAccess, &subFields) != nil {
-                               acc.Access = &getField(fieldUserAccess, &subFields).Data
+                       if getField(FieldUserAccess, &subFields) != nil {
+                               copy(acc.Access[:], getField(FieldUserAccess, &subFields).Data)
                         }
  
                         err = cc.Server.UpdateUser(
                         }
  
                         err = cc.Server.UpdateUser(
-                               DecodeUserString(getField(fieldData, &subFields).Data),
-                               DecodeUserString(getField(fieldUserLogin, &subFields).Data),
-                               string(getField(fieldUserName, &subFields).Data),
+                               string(encodeString(getField(FieldData, &subFields).Data)),
+                               string(encodeString(getField(FieldUserLogin, &subFields).Data)),
+                               string(getField(FieldUserName, &subFields).Data),
                                 acc.Password,
                                 acc.Password,
-                               *acc.Access,
+                               acc.Access,
                         )
                         if err != nil {
                                 return res, err
                         }
                 } else {
                         )
                         if err != nil {
                                 return res, err
                         }
                 } else {
-                       cc.logger.Infow("CreateUser", "login", login)
-
-                       if !authorize(cc.Account.Access, accessCreateUser) {
+                       if !cc.Authorize(accessCreateUser) {
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to create new accounts."))
                                 res = append(res, cc.NewErrReply(t, "You are not allowed to create new accounts."))
-                               return res, err
+                               return res, nil
                         }
  
                         }
  
-                       err := cc.Server.NewUser(
-                               login,
-                               string(getField(fieldUserName, &subFields).Data),
-                               string(getField(fieldUserPassword, &subFields).Data),
-                               getField(fieldUserAccess, &subFields).Data,
-                       )
+                       cc.logger.Info("CreateUser", "login", userLogin)
+
+                       newAccess := accessBitmap{}
+                       copy(newAccess[:], getField(FieldUserAccess, &subFields).Data)
+
+                       // Prevent account from creating new account with greater permission
+                       for i := 0; i < 64; i++ {
+                               if newAccess.IsSet(i) {
+                                       if !cc.Authorize(i) {
+                                               return append(res, cc.NewErrReply(t, "Cannot create account with more access than yourself.")), nil
+                                       }
+                               }
+                       }
+
+                       err = cc.Server.NewUser(userLogin, string(getField(FieldUserName, &subFields).Data), string(getField(FieldUserPassword, &subFields).Data), newAccess)
                         if err != nil {
                         if err != nil {
-                               return []Transaction{}, err
+                               return append(res, cc.NewErrReply(t, "Cannot create account because there is already an account with that login.")), nil
                         }
                 }
         }
                         }
                 }
         }
@@ -796,12 +899,12 @@ func HandleUpdateUser(cc *ClientConn, t *Transaction) (res []Transaction, err er
  
  // HandleNewUser creates a new user account
  func HandleNewUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  
  // HandleNewUser creates a new user account
  func HandleNewUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessCreateUser) {
+       if !cc.Authorize(accessCreateUser) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to create new accounts."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to create new accounts."))
                 return res, err
         }
  
-       login := DecodeUserString(t.GetField(fieldUserLogin).Data)
+       login := string(encodeString(t.GetField(FieldUserLogin).Data))
  
         // If the account already dataFile, reply with an error
         if _, ok := cc.Server.Accounts[login]; ok {
  
         // If the account already dataFile, reply with an error
         if _, ok := cc.Server.Accounts[login]; ok {
@@ -809,13 +912,22 @@ func HandleNewUser(cc *ClientConn, t *Transaction) (res []Transaction, err error
                 return res, err
         }
  
                 return res, err
         }
  
-       if err := cc.Server.NewUser(
-               login,
-               string(t.GetField(fieldUserName).Data),
-               string(t.GetField(fieldUserPassword).Data),
-               t.GetField(fieldUserAccess).Data,
-       ); err != nil {
-               return []Transaction{}, err
+       newAccess := accessBitmap{}
+       copy(newAccess[:], t.GetField(FieldUserAccess).Data)
+
+       // Prevent account from creating new account with greater permission
+       for i := 0; i < 64; i++ {
+               if newAccess.IsSet(i) {
+                       if !cc.Authorize(i) {
+                               res = append(res, cc.NewErrReply(t, "Cannot create account with more access than yourself."))
+                               return res, err
+                       }
+               }
+       }
+
+       if err := cc.Server.NewUser(login, string(t.GetField(FieldUserName).Data), string(t.GetField(FieldUserPassword).Data), newAccess); err != nil {
+               res = append(res, cc.NewErrReply(t, "Cannot create account because there is already an account with that login."))
+               return res, err
         }
  
         res = append(res, cc.NewReply(t))
         }
  
         res = append(res, cc.NewReply(t))
@@ -823,13 +935,12 @@ func HandleNewUser(cc *ClientConn, t *Transaction) (res []Transaction, err error
  }
  
  func HandleDeleteUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleDeleteUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessDeleteUser) {
+       if !cc.Authorize(accessDeleteUser) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to delete accounts."))
                 res = append(res, cc.NewErrReply(t, "You are not allowed to delete accounts."))
-               return res, err
+               return res, nil
         }
  
         }
  
-       // TODO: Handle case where account doesn't exist; e.g. delete race condition
-       login := DecodeUserString(t.GetField(fieldUserLogin).Data)
+       login := string(encodeString(t.GetField(FieldUserLogin).Data))
  
         if err := cc.Server.DeleteUser(login); err != nil {
                 return res, err
  
         if err := cc.Server.DeleteUser(login); err != nil {
                 return res, err
@@ -841,47 +952,36 @@ func HandleDeleteUser(cc *ClientConn, t *Transaction) (res []Transaction, err er
  
  // HandleUserBroadcast sends an Administrator Message to all connected clients of the server
  func HandleUserBroadcast(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  
  // HandleUserBroadcast sends an Administrator Message to all connected clients of the server
  func HandleUserBroadcast(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessBroadcast) {
+       if !cc.Authorize(accessBroadcast) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to send broadcast messages."))
                 return res, err
         }
  
         cc.sendAll(
                 res = append(res, cc.NewErrReply(t, "You are not allowed to send broadcast messages."))
                 return res, err
         }
  
         cc.sendAll(
-               tranServerMsg,
-               NewField(fieldData, t.GetField(tranGetMsgs).Data),
-               NewField(fieldChatOptions, []byte{0}),
+               TranServerMsg,
+               NewField(FieldData, t.GetField(TranGetMsgs).Data),
+               NewField(FieldChatOptions, []byte{0}),
         )
  
         res = append(res, cc.NewReply(t))
         return res, err
  }
  
         )
  
         res = append(res, cc.NewReply(t))
         return res, err
  }
  
-func byteToInt(bytes []byte) (int, error) {
-       switch len(bytes) {
-       case 2:
-               return int(binary.BigEndian.Uint16(bytes)), nil
-       case 4:
-               return int(binary.BigEndian.Uint32(bytes)), nil
-       }
-
-       return 0, errors.New("unknown byte length")
-}
-
  // HandleGetClientInfoText returns user information for the specific user.
  //
  // Fields used in the request:
  // 103 User ID
  //
  // Fields used in the reply:
  // HandleGetClientInfoText returns user information for the specific user.
  //
  // Fields used in the request:
  // 103 User ID
  //
  // Fields used in the reply:
-// 102 User name
+// 102 User Name
  // 101 Data            User info text string
  func HandleGetClientInfoText(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // 101 Data            User info text string
  func HandleGetClientInfoText(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessGetClientInfo) {
+       if !cc.Authorize(accessGetClientInfo) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to get client info."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to get client info."))
                 return res, err
         }
  
-       clientID, _ := byteToInt(t.GetField(fieldUserID).Data)
+       clientID, _ := byteToInt(t.GetField(FieldUserID).Data)
  
         clientConn := cc.Server.Clients[uint16(clientID)]
         if clientConn == nil {
  
         clientConn := cc.Server.Clients[uint16(clientID)]
         if clientConn == nil {
@@ -889,64 +989,67 @@ func HandleGetClientInfoText(cc *ClientConn, t *Transaction) (res []Transaction,
         }
  
         res = append(res, cc.NewReply(t,
         }
  
         res = append(res, cc.NewReply(t,
-               NewField(fieldData, []byte(clientConn.String())),
-               NewField(fieldUserName, clientConn.UserName),
+               NewField(FieldData, []byte(clientConn.String())),
+               NewField(FieldUserName, clientConn.UserName),
         ))
         return res, err
  }
  
  func HandleGetUserNameList(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
         ))
         return res, err
  }
  
  func HandleGetUserNameList(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       res = append(res, cc.NewReply(t, cc.Server.connectedUsers()...))
-
-       return res, err
+       return []Transaction{cc.NewReply(t, cc.Server.connectedUsers()...)}, nil
  }
  
  func HandleTranAgreed(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleTranAgreed(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       cc.Agreed = true
-       cc.UserName = t.GetField(fieldUserName).Data
-       *cc.Icon = t.GetField(fieldUserIconID).Data
+       if t.GetField(FieldUserName).Data != nil {
+               if cc.Authorize(accessAnyName) {
+                       cc.UserName = t.GetField(FieldUserName).Data
+               } else {
+                       cc.UserName = []byte(cc.Account.Name)
+               }
+       }
+
+       cc.Icon = t.GetField(FieldUserIconID).Data
  
  
-       cc.logger = cc.logger.With("name", string(cc.UserName))
-       cc.logger.Infow("Login successful", "clientVersion", fmt.Sprintf("%x", *cc.Version))
+       cc.logger = cc.logger.With("Name", string(cc.UserName))
+       cc.logger.Info("Login successful", "clientVersion", fmt.Sprintf("%v", func() int { i, _ := byteToInt(cc.Version); return i }()))
  
  
-       options := t.GetField(fieldOptions).Data
+       options := t.GetField(FieldOptions).Data
         optBitmap := big.NewInt(int64(binary.BigEndian.Uint16(options)))
  
         optBitmap := big.NewInt(int64(binary.BigEndian.Uint16(options)))
  
-       flagBitmap := big.NewInt(int64(binary.BigEndian.Uint16(*cc.Flags)))
+       flagBitmap := big.NewInt(int64(binary.BigEndian.Uint16(cc.Flags)))
  
         // Check refuse private PM option
  
         // Check refuse private PM option
-       if optBitmap.Bit(refusePM) == 1 {
-               flagBitmap.SetBit(flagBitmap, userFlagRefusePM, 1)
-               binary.BigEndian.PutUint16(*cc.Flags, uint16(flagBitmap.Int64()))
+       if optBitmap.Bit(UserOptRefusePM) == 1 {
+               flagBitmap.SetBit(flagBitmap, UserFlagRefusePM, 1)
+               binary.BigEndian.PutUint16(cc.Flags, uint16(flagBitmap.Int64()))
         }
  
         // Check refuse private chat option
         }
  
         // Check refuse private chat option
-       if optBitmap.Bit(refuseChat) == 1 {
-               flagBitmap.SetBit(flagBitmap, userFLagRefusePChat, 1)
-               binary.BigEndian.PutUint16(*cc.Flags, uint16(flagBitmap.Int64()))
+       if optBitmap.Bit(UserOptRefuseChat) == 1 {
+               flagBitmap.SetBit(flagBitmap, UserFlagRefusePChat, 1)
+               binary.BigEndian.PutUint16(cc.Flags, uint16(flagBitmap.Int64()))
         }
  
         // Check auto response
         }
  
         // Check auto response
-       if optBitmap.Bit(autoResponse) == 1 {
-               cc.AutoReply = t.GetField(fieldAutomaticResponse).Data
+       if optBitmap.Bit(UserOptAutoResponse) == 1 {
+               cc.AutoReply = t.GetField(FieldAutomaticResponse).Data
         } else {
                 cc.AutoReply = []byte{}
         }
  
         } else {
                 cc.AutoReply = []byte{}
         }
  
-       for _, t := range cc.notifyOthers(
+       trans := cc.notifyOthers(
                 *NewTransaction(
                 *NewTransaction(
-                       tranNotifyChangeUser, nil,
-                       NewField(fieldUserName, cc.UserName),
-                       NewField(fieldUserID, *cc.ID),
-                       NewField(fieldUserIconID, *cc.Icon),
-                       NewField(fieldUserFlags, *cc.Flags),
+                       TranNotifyChangeUser, nil,
+                       NewField(FieldUserName, cc.UserName),
+                       NewField(FieldUserID, *cc.ID),
+                       NewField(FieldUserIconID, cc.Icon),
+                       NewField(FieldUserFlags, cc.Flags),
                 ),
                 ),
-       ) {
-               cc.Server.outbox <- t
-       }
+       )
+       res = append(res, trans...)
  
         if cc.Server.Config.BannerFile != "" {
  
         if cc.Server.Config.BannerFile != "" {
-               cc.Server.outbox <- *NewTransaction(tranServerBanner, cc.ID, NewField(fieldBannerType, []byte("JPEG")))
+               res = append(res, *NewTransaction(TranServerBanner, cc.ID, NewField(FieldBannerType, []byte("JPEG"))))
         }
  
         res = append(res, cc.NewReply(t))
         }
  
         res = append(res, cc.NewReply(t))
@@ -954,20 +1057,11 @@ func HandleTranAgreed(cc *ClientConn, t *Transaction) (res []Transaction, err er
         return res, err
  }
  
         return res, err
  }
  
-const defaultNewsDateFormat = "Jan02 15:04" // Jun23 20:49
-//  "Mon, 02 Jan 2006 15:04:05 MST"
-
-const defaultNewsTemplate = `From %s (%s):
-
-%s
-
-__________________________________________________________`
-
  // HandleTranOldPostNews updates the flat news
  // Fields used in this request:
  // 101 Data
  func HandleTranOldPostNews(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // HandleTranOldPostNews updates the flat news
  // Fields used in this request:
  // 101 Data
  func HandleTranOldPostNews(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessNewsPostArt) {
+       if !cc.Authorize(accessNewsPostArt) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to post news."))
                 return res, err
         }
                 res = append(res, cc.NewErrReply(t, "You are not allowed to post news."))
                 return res, err
         }
@@ -985,21 +1079,21 @@ func HandleTranOldPostNews(cc *ClientConn, t *Transaction) (res []Transaction, e
                 newsTemplate = cc.Server.Config.NewsDelimiter
         }
  
                 newsTemplate = cc.Server.Config.NewsDelimiter
         }
  
-       newsPost := fmt.Sprintf(newsTemplate+"\r", cc.UserName, time.Now().Format(newsDateTemplate), t.GetField(fieldData).Data)
-       newsPost = strings.Replace(newsPost, "\n", "\r", -1)
+       newsPost := fmt.Sprintf(newsTemplate+"\r", cc.UserName, time.Now().Format(newsDateTemplate), t.GetField(FieldData).Data)
+       newsPost = strings.ReplaceAll(newsPost, "\n", "\r")
  
         // update news in memory
         cc.Server.FlatNews = append([]byte(newsPost), cc.Server.FlatNews...)
  
         // update news on disk
  
         // update news in memory
         cc.Server.FlatNews = append([]byte(newsPost), cc.Server.FlatNews...)
  
         // update news on disk
-       if err := ioutil.WriteFile(cc.Server.ConfigDir+"MessageBoard.txt", cc.Server.FlatNews, 0644); err != nil {
+       if err := cc.Server.FS.WriteFile(filepath.Join(cc.Server.ConfigDir, "MessageBoard.txt"), cc.Server.FlatNews, 0644); err != nil {
                 return res, err
         }
  
         // Notify all clients of updated news
         cc.sendAll(
                 return res, err
         }
  
         // Notify all clients of updated news
         cc.sendAll(
-               tranNewMsg,
-               NewField(fieldData, []byte(newsPost)),
+               TranNewMsg,
+               NewField(FieldData, []byte(newsPost)),
         )
  
         res = append(res, cc.NewReply(t))
         )
  
         res = append(res, cc.NewReply(t))
@@ -1007,36 +1101,75 @@ func HandleTranOldPostNews(cc *ClientConn, t *Transaction) (res []Transaction, e
  }
  
  func HandleDisconnectUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleDisconnectUser(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessDisconUser) {
+       if !cc.Authorize(accessDisconUser) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to disconnect users."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to disconnect users."))
                 return res, err
         }
  
-       clientConn := cc.Server.Clients[binary.BigEndian.Uint16(t.GetField(fieldUserID).Data)]
+       clientConn := cc.Server.Clients[binary.BigEndian.Uint16(t.GetField(FieldUserID).Data)]
  
  
-       if authorize(clientConn.Account.Access, accessCannotBeDiscon) {
+       if clientConn.Authorize(accessCannotBeDiscon) {
                 res = append(res, cc.NewErrReply(t, clientConn.Account.Login+" is not allowed to be disconnected."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, clientConn.Account.Login+" is not allowed to be disconnected."))
                 return res, err
         }
  
-       if err := clientConn.Connection.Close(); err != nil {
-               return res, err
+       // If FieldOptions is set, then the client IP is banned in addition to disconnected.
+       // 00 01 = temporary ban
+       // 00 02 = permanent ban
+       if t.GetField(FieldOptions).Data != nil {
+               switch t.GetField(FieldOptions).Data[1] {
+               case 1:
+                       // send message: "You are temporarily banned on this server"
+                       cc.logger.Info("Disconnect & temporarily ban " + string(clientConn.UserName))
+
+                       res = append(res, *NewTransaction(
+                               TranServerMsg,
+                               clientConn.ID,
+                               NewField(FieldData, []byte("You are temporarily banned on this server")),
+                               NewField(FieldChatOptions, []byte{0, 0}),
+                       ))
+
+                       banUntil := time.Now().Add(tempBanDuration)
+                       cc.Server.banList[strings.Split(clientConn.RemoteAddr, ":")[0]] = &banUntil
+               case 2:
+                       // send message: "You are permanently banned on this server"
+                       cc.logger.Info("Disconnect & ban " + string(clientConn.UserName))
+
+                       res = append(res, *NewTransaction(
+                               TranServerMsg,
+                               clientConn.ID,
+                               NewField(FieldData, []byte("You are permanently banned on this server")),
+                               NewField(FieldChatOptions, []byte{0, 0}),
+                       ))
+
+                       cc.Server.banList[strings.Split(clientConn.RemoteAddr, ":")[0]] = nil
+               }
+
+               err := cc.Server.writeBanList()
+               if err != nil {
+                       return res, err
+               }
         }
  
         }
  
-       res = append(res, cc.NewReply(t))
-       return res, err
+       // TODO: remove this awful hack
+       go func() {
+               time.Sleep(1 * time.Second)
+               clientConn.Disconnect()
+       }()
+
+       return append(res, cc.NewReply(t)), err
  }
  
  // HandleGetNewsCatNameList returns a list of news categories for a path
  // Fields used in the request:
  // 325 News path       (Optional)
  func HandleGetNewsCatNameList(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  // HandleGetNewsCatNameList returns a list of news categories for a path
  // Fields used in the request:
  // 325 News path       (Optional)
  func HandleGetNewsCatNameList(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessNewsReadArt) {
+       if !cc.Authorize(accessNewsReadArt) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to read news."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to read news."))
                 return res, err
         }
  
-       pathStrs := ReadNewsPath(t.GetField(fieldNewsPath).Data)
+       pathStrs := ReadNewsPath(t.GetField(FieldNewsPath).Data)
         cats := cc.Server.GetNewsCatByPath(pathStrs)
  
         // To store the keys in slice in sorted order
         cats := cc.Server.GetNewsCatByPath(pathStrs)
  
         // To store the keys in slice in sorted order
@@ -1053,7 +1186,7 @@ func HandleGetNewsCatNameList(cc *ClientConn, t *Transaction) (res []Transaction
                 cat := cats[k]
                 b, _ := cat.MarshalBinary()
                 fieldData = append(fieldData, NewField(
                 cat := cats[k]
                 b, _ := cat.MarshalBinary()
                 fieldData = append(fieldData, NewField(
-                       fieldNewsCatListData15,
+                       FieldNewsCatListData15,
                         b,
                 ))
         }
                         b,
                 ))
         }
@@ -1063,18 +1196,18 @@ func HandleGetNewsCatNameList(cc *ClientConn, t *Transaction) (res []Transaction
  }
  
  func HandleNewNewsCat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleNewNewsCat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessNewsCreateCat) {
+       if !cc.Authorize(accessNewsCreateCat) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to create news categories."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to create news categories."))
                 return res, err
         }
  
-       name := string(t.GetField(fieldNewsCatName).Data)
-       pathStrs := ReadNewsPath(t.GetField(fieldNewsPath).Data)
+       name := string(t.GetField(FieldNewsCatName).Data)
+       pathStrs := ReadNewsPath(t.GetField(FieldNewsPath).Data)
  
         cats := cc.Server.GetNewsCatByPath(pathStrs)
         cats[name] = NewsCategoryListData15{
                 Name:     name,
  
         cats := cc.Server.GetNewsCatByPath(pathStrs)
         cats[name] = NewsCategoryListData15{
                 Name:     name,
-               Type:     []byte{0, 3},
+               Type:     [2]byte{0, 3},
                 Articles: map[uint32]*NewsArtData{},
                 SubCats:  make(map[string]NewsCategoryListData15),
         }
                 Articles: map[uint32]*NewsArtData{},
                 SubCats:  make(map[string]NewsCategoryListData15),
         }
@@ -1087,23 +1220,21 @@ func HandleNewNewsCat(cc *ClientConn, t *Transaction) (res []Transaction, err er
  }
  
  // Fields used in the request:
  }
  
  // Fields used in the request:
-// 322 News category name
+// 322 News category Name
  // 325 News path
  func HandleNewNewsFldr(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // 325 News path
  func HandleNewNewsFldr(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessNewsCreateFldr) {
+       if !cc.Authorize(accessNewsCreateFldr) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to create news folders."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to create news folders."))
                 return res, err
         }
  
-       name := string(t.GetField(fieldFileName).Data)
-       pathStrs := ReadNewsPath(t.GetField(fieldNewsPath).Data)
-
-       cc.logger.Infof("Creating new news folder %s", name)
+       name := string(t.GetField(FieldFileName).Data)
+       pathStrs := ReadNewsPath(t.GetField(FieldNewsPath).Data)
  
         cats := cc.Server.GetNewsCatByPath(pathStrs)
         cats[name] = NewsCategoryListData15{
                 Name:     name,
  
         cats := cc.Server.GetNewsCatByPath(pathStrs)
         cats[name] = NewsCategoryListData15{
                 Name:     name,
-               Type:     []byte{0, 2},
+               Type:     [2]byte{0, 2},
                 Articles: map[uint32]*NewsArtData{},
                 SubCats:  make(map[string]NewsCategoryListData15),
         }
                 Articles: map[uint32]*NewsArtData{},
                 SubCats:  make(map[string]NewsCategoryListData15),
         }
@@ -1114,17 +1245,20 @@ func HandleNewNewsFldr(cc *ClientConn, t *Transaction) (res []Transaction, err e
         return res, err
  }
  
         return res, err
  }
  
+// HandleGetNewsArtData gets the list of article names at the specified news path.
+
  // Fields used in the request:
  // 325 News path       Optional
  // Fields used in the request:
  // 325 News path       Optional
-//
-// Reply fields:
+
+// Fields used in the reply:
  // 321 News article list data  Optional
  func HandleGetNewsArtNameList(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // 321 News article list data  Optional
  func HandleGetNewsArtNameList(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessNewsReadArt) {
+       if !cc.Authorize(accessNewsReadArt) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to read news."))
                 res = append(res, cc.NewErrReply(t, "You are not allowed to read news."))
-               return res, err
+               return res, nil
         }
         }
-       pathStrs := ReadNewsPath(t.GetField(fieldNewsPath).Data)
+
+       pathStrs := ReadNewsPath(t.GetField(FieldNewsPath).Data)
  
         var cat NewsCategoryListData15
         cats := cc.Server.ThreadedNews.Categories
  
         var cat NewsCategoryListData15
         cats := cc.Server.ThreadedNews.Categories
@@ -1136,77 +1270,83 @@ func HandleGetNewsArtNameList(cc *ClientConn, t *Transaction) (res []Transaction
  
         nald := cat.GetNewsArtListData()
  
  
         nald := cat.GetNewsArtListData()
  
-       res = append(res, cc.NewReply(t, NewField(fieldNewsArtListData, nald.Payload())))
-       return res, err
+       b, err := io.ReadAll(&nald)
+       if err != nil {
+               return res, fmt.Errorf("error loading news articles: %w", err)
+       }
+
+       res = append(res, cc.NewReply(t, NewField(FieldNewsArtListData, b)))
+       return res, nil
  }
  
  }
  
+// HandleGetNewsArtData requests information about the specific news article.
+// Fields used in the request:
+//
+// Request fields
+// 325 News path
+// 326 News article ID
+// 327 News article data flavor
+//
+// Fields used in the reply:
+// 328 News article title
+// 329 News article poster
+// 330 News article date
+// 331 Previous article ID
+// 332 Next article ID
+// 335 Parent article ID
+// 336 First child article ID
+// 327 News article data flavor        "Should be “text/plain”
+// 333 News article data       Optional (if data flavor is “text/plain”)
  func HandleGetNewsArtData(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  func HandleGetNewsArtData(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessNewsReadArt) {
+       if !cc.Authorize(accessNewsReadArt) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to read news."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to read news."))
                 return res, err
         }
  
-       // Request fields
-       // 325  News fp
-       // 326  News article ID
-       // 327  News article data flavor
-
-       pathStrs := ReadNewsPath(t.GetField(fieldNewsPath).Data)
-
         var cat NewsCategoryListData15
         cats := cc.Server.ThreadedNews.Categories
  
         var cat NewsCategoryListData15
         cats := cc.Server.ThreadedNews.Categories
  
-       for _, fp := range pathStrs {
+       for _, fp := range ReadNewsPath(t.GetField(FieldNewsPath).Data) {
                 cat = cats[fp]
                 cats = cats[fp].SubCats
         }
                 cat = cats[fp]
                 cats = cats[fp].SubCats
         }
-       newsArtID := t.GetField(fieldNewsArtID).Data
  
  
-       convertedArtID := binary.BigEndian.Uint16(newsArtID)
+       // The official Hotline clients will send the article ID as 2 bytes if possible, but
+       // some third party clients such as Frogblast and Heildrun will always send 4 bytes
+       convertedID, err := byteToInt(t.GetField(FieldNewsArtID).Data)
+       if err != nil {
+               return res, err
+       }
  
  
-       art := cat.Articles[uint32(convertedArtID)]
+       art := cat.Articles[uint32(convertedID)]
         if art == nil {
                 res = append(res, cc.NewReply(t))
                 return res, err
         }
  
         if art == nil {
                 res = append(res, cc.NewReply(t))
                 return res, err
         }
  
-       // Reply fields
-       // 328  News article title
-       // 329  News article poster
-       // 330  News article date
-       // 331  Previous article ID
-       // 332  Next article ID
-       // 335  Parent article ID
-       // 336  First child article ID
-       // 327  News article data flavor        "Should be “text/plain”
-       // 333  News article data       Optional (if data flavor is “text/plain”)
-
         res = append(res, cc.NewReply(t,
         res = append(res, cc.NewReply(t,
-               NewField(fieldNewsArtTitle, []byte(art.Title)),
-               NewField(fieldNewsArtPoster, []byte(art.Poster)),
-               NewField(fieldNewsArtDate, art.Date),
-               NewField(fieldNewsArtPrevArt, art.PrevArt),
-               NewField(fieldNewsArtNextArt, art.NextArt),
-               NewField(fieldNewsArtParentArt, art.ParentArt),
-               NewField(fieldNewsArt1stChildArt, art.FirstChildArt),
-               NewField(fieldNewsArtDataFlav, []byte("text/plain")),
-               NewField(fieldNewsArtData, []byte(art.Data)),
+               NewField(FieldNewsArtTitle, []byte(art.Title)),
+               NewField(FieldNewsArtPoster, []byte(art.Poster)),
+               NewField(FieldNewsArtDate, art.Date[:]),
+               NewField(FieldNewsArtPrevArt, art.PrevArt[:]),
+               NewField(FieldNewsArtNextArt, art.NextArt[:]),
+               NewField(FieldNewsArtParentArt, art.ParentArt[:]),
+               NewField(FieldNewsArt1stChildArt, art.FirstChildArt[:]),
+               NewField(FieldNewsArtDataFlav, []byte("text/plain")),
+               NewField(FieldNewsArtData, []byte(art.Data)),
         ))
         return res, err
  }
  
         ))
         return res, err
  }
  
+// HandleDelNewsItem deletes an existing threaded news folder or category from the server.
+// Fields used in the request:
+// 325 News path
+// Fields used in the reply:
+// None
  func HandleDelNewsItem(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  func HandleDelNewsItem(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       // Has multiple access flags: News Delete Folder (37) or News Delete Category (35)
-       // TODO: Implement
-
-       pathStrs := ReadNewsPath(t.GetField(fieldNewsPath).Data)
-
-       // TODO: determine if path is a Folder (Bundle) or Category and check for permission
-
-       cc.logger.Infof("DelNewsItem %v", pathStrs)
+       pathStrs := ReadNewsPath(t.GetField(FieldNewsPath).Data)
  
         cats := cc.Server.ThreadedNews.Categories
  
         cats := cc.Server.ThreadedNews.Categories
-
         delName := pathStrs[len(pathStrs)-1]
         if len(pathStrs) > 1 {
                 for _, fp := range pathStrs[0 : len(pathStrs)-1] {
         delName := pathStrs[len(pathStrs)-1]
         if len(pathStrs) > 1 {
                 for _, fp := range pathStrs[0 : len(pathStrs)-1] {
@@ -1214,21 +1354,27 @@ func HandleDelNewsItem(cc *ClientConn, t *Transaction) (res []Transaction, err e
                 }
         }
  
                 }
         }
  
+       if cats[delName].Type == [2]byte{0, 3} {
+               if !cc.Authorize(accessNewsDeleteCat) {
+                       return append(res, cc.NewErrReply(t, "You are not allowed to delete news categories.")), nil
+               }
+       } else {
+               if !cc.Authorize(accessNewsDeleteFldr) {
+                       return append(res, cc.NewErrReply(t, "You are not allowed to delete news folders.")), nil
+               }
+       }
+
         delete(cats, delName)
  
         delete(cats, delName)
  
-       err = cc.Server.writeThreadedNews()
-       if err != nil {
+       if err := cc.Server.writeThreadedNews(); err != nil {
                 return res, err
         }
  
                 return res, err
         }
  
-       // Reply params: none
-       res = append(res, cc.NewReply(t))
-
-       return res, err
+       return append(res, cc.NewReply(t)), nil
  }
  
  func HandleDelNewsArt(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleDelNewsArt(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessNewsDeleteArt) {
+       if !cc.Authorize(accessNewsDeleteArt) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to delete news articles."))
                 return res, err
         }
                 res = append(res, cc.NewErrReply(t, "You are not allowed to delete news articles."))
                 return res, err
         }
@@ -1237,8 +1383,11 @@ func HandleDelNewsArt(cc *ClientConn, t *Transaction) (res []Transaction, err er
         // 325  News path
         // 326  News article ID
         // 337  News article – recursive delete       Delete child articles (1) or not (0)
         // 325  News path
         // 326  News article ID
         // 337  News article – recursive delete       Delete child articles (1) or not (0)
-       pathStrs := ReadNewsPath(t.GetField(fieldNewsPath).Data)
-       ID := binary.BigEndian.Uint16(t.GetField(fieldNewsArtID).Data)
+       pathStrs := ReadNewsPath(t.GetField(FieldNewsPath).Data)
+       ID, err := byteToInt(t.GetField(FieldNewsArtID).Data)
+       if err != nil {
+               return res, err
+       }
  
         // TODO: Delete recursive
         cats := cc.Server.GetNewsCatByPath(pathStrs[:len(pathStrs)-1])
  
         // TODO: Delete recursive
         cats := cc.Server.GetNewsCatByPath(pathStrs[:len(pathStrs)-1])
@@ -1265,27 +1414,38 @@ func HandleDelNewsArt(cc *ClientConn, t *Transaction) (res []Transaction, err er
  // 327 News article data flavor                Currently “text/plain”
  // 333 News article data
  func HandlePostNewsArt(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // 327 News article data flavor                Currently “text/plain”
  // 333 News article data
  func HandlePostNewsArt(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessNewsPostArt) {
+       if !cc.Authorize(accessNewsPostArt) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to post news articles."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to post news articles."))
                 return res, err
         }
  
-       pathStrs := ReadNewsPath(t.GetField(fieldNewsPath).Data)
+       pathStrs := ReadNewsPath(t.GetField(FieldNewsPath).Data)
         cats := cc.Server.GetNewsCatByPath(pathStrs[:len(pathStrs)-1])
  
         catName := pathStrs[len(pathStrs)-1]
         cat := cats[catName]
  
         cats := cc.Server.GetNewsCatByPath(pathStrs[:len(pathStrs)-1])
  
         catName := pathStrs[len(pathStrs)-1]
         cat := cats[catName]
  
+       artID, err := byteToInt(t.GetField(FieldNewsArtID).Data)
+       if err != nil {
+               return res, err
+       }
+       convertedArtID := uint32(artID)
+       bs := make([]byte, 4)
+       binary.BigEndian.PutUint32(bs, convertedArtID)
+
+       cc.Server.mux.Lock()
+       defer cc.Server.mux.Unlock()
+
         newArt := NewsArtData{
         newArt := NewsArtData{
-               Title:         string(t.GetField(fieldNewsArtTitle).Data),
+               Title:         string(t.GetField(FieldNewsArtTitle).Data),
                 Poster:        string(cc.UserName),
                 Date:          toHotlineTime(time.Now()),
                 Poster:        string(cc.UserName),
                 Date:          toHotlineTime(time.Now()),
-               PrevArt:       []byte{0, 0, 0, 0},
-               NextArt:       []byte{0, 0, 0, 0},
-               ParentArt:     append([]byte{0, 0}, t.GetField(fieldNewsArtID).Data...),
-               FirstChildArt: []byte{0, 0, 0, 0},
+               PrevArt:       [4]byte{},
+               NextArt:       [4]byte{},
+               ParentArt:     [4]byte(bs),
+               FirstChildArt: [4]byte{},
                 DataFlav:      []byte("text/plain"),
                 DataFlav:      []byte("text/plain"),
-               Data:          string(t.GetField(fieldNewsArtData).Data),
+               Data:          string(t.GetField(FieldNewsArtData).Data),
         }
  
         var keys []int
         }
  
         var keys []int
@@ -1299,19 +1459,19 @@ func HandlePostNewsArt(cc *ClientConn, t *Transaction) (res []Transaction, err e
                 prevID := uint32(keys[len(keys)-1])
                 nextID = prevID + 1
  
                 prevID := uint32(keys[len(keys)-1])
                 nextID = prevID + 1
  
-               binary.BigEndian.PutUint32(newArt.PrevArt, prevID)
+               binary.BigEndian.PutUint32(newArt.PrevArt[:], prevID)
  
                 // Set next article ID
  
                 // Set next article ID
-               binary.BigEndian.PutUint32(cat.Articles[prevID].NextArt, nextID)
+               binary.BigEndian.PutUint32(cat.Articles[prevID].NextArt[:], nextID)
         }
  
         // Update parent article with first child reply
         }
  
         // Update parent article with first child reply
-       parentID := binary.BigEndian.Uint16(t.GetField(fieldNewsArtID).Data)
+       parentID := convertedArtID
         if parentID != 0 {
         if parentID != 0 {
-               parentArt := cat.Articles[uint32(parentID)]
+               parentArt := cat.Articles[parentID]
  
  
-               if bytes.Equal(parentArt.FirstChildArt, []byte{0, 0, 0, 0}) {
-                       binary.BigEndian.PutUint32(parentArt.FirstChildArt, nextID)
+               if parentArt.FirstChildArt == [4]byte{0, 0, 0, 0} {
+                       binary.BigEndian.PutUint32(parentArt.FirstChildArt[:], nextID)
                 }
         }
  
                 }
         }
  
@@ -1328,30 +1488,30 @@ func HandlePostNewsArt(cc *ClientConn, t *Transaction) (res []Transaction, err e
  
  // HandleGetMsgs returns the flat news data
  func HandleGetMsgs(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  
  // HandleGetMsgs returns the flat news data
  func HandleGetMsgs(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessNewsReadArt) {
+       if !cc.Authorize(accessNewsReadArt) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to read news."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to read news."))
                 return res, err
         }
  
-       res = append(res, cc.NewReply(t, NewField(fieldData, cc.Server.FlatNews)))
+       res = append(res, cc.NewReply(t, NewField(FieldData, cc.Server.FlatNews)))
  
         return res, err
  }
  
  func HandleDownloadFile(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  
         return res, err
  }
  
  func HandleDownloadFile(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessDownloadFile) {
+       if !cc.Authorize(accessDownloadFile) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to download files."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to download files."))
                 return res, err
         }
  
-       fileName := t.GetField(fieldFileName).Data
-       filePath := t.GetField(fieldFilePath).Data
-       resumeData := t.GetField(fieldFileResumeData).Data
+       fileName := t.GetField(FieldFileName).Data
+       filePath := t.GetField(FieldFilePath).Data
+       resumeData := t.GetField(FieldFileResumeData).Data
  
         var dataOffset int64
         var frd FileResumeData
         if resumeData != nil {
  
         var dataOffset int64
         var frd FileResumeData
         if resumeData != nil {
-               if err := frd.UnmarshalBinary(t.GetField(fieldFileResumeData).Data); err != nil {
+               if err := frd.UnmarshalBinary(t.GetField(FieldFileResumeData).Data); err != nil {
                         return res, err
                 }
                 // TODO: handle rsrc fork offset
                         return res, err
                 }
                 // TODO: handle rsrc fork offset
@@ -1375,7 +1535,7 @@ func HandleDownloadFile(cc *ClientConn, t *Transaction) (res []Transaction, err
         // TODO: refactor to remove this
         if resumeData != nil {
                 var frd FileResumeData
         // TODO: refactor to remove this
         if resumeData != nil {
                 var frd FileResumeData
-               if err := frd.UnmarshalBinary(t.GetField(fieldFileResumeData).Data); err != nil {
+               if err := frd.UnmarshalBinary(t.GetField(FieldFileResumeData).Data); err != nil {
                         return res, err
                 }
                 ft.fileResumeData = &frd
                         return res, err
                 }
                 ft.fileResumeData = &frd
@@ -1384,16 +1544,16 @@ func HandleDownloadFile(cc *ClientConn, t *Transaction) (res []Transaction, err
         // Optional field for when a HL v1.5+ client requests file preview
         // Used only for TEXT, JPEG, GIFF, BMP or PICT files
         // The value will always be 2
         // Optional field for when a HL v1.5+ client requests file preview
         // Used only for TEXT, JPEG, GIFF, BMP or PICT files
         // The value will always be 2
-       if t.GetField(fieldFileTransferOptions).Data != nil {
-               ft.options = t.GetField(fieldFileTransferOptions).Data
+       if t.GetField(FieldFileTransferOptions).Data != nil {
+               ft.options = t.GetField(FieldFileTransferOptions).Data
                 xferSize = hlFile.ffo.FlatFileDataForkHeader.DataSize[:]
         }
  
         res = append(res, cc.NewReply(t,
                 xferSize = hlFile.ffo.FlatFileDataForkHeader.DataSize[:]
         }
  
         res = append(res, cc.NewReply(t,
-               NewField(fieldRefNum, ft.refNum[:]),
-               NewField(fieldWaitingCount, []byte{0x00, 0x00}), // TODO: Implement waiting count
-               NewField(fieldTransferSize, xferSize),
-               NewField(fieldFileSize, hlFile.ffo.FlatFileDataForkHeader.DataSize[:]),
+               NewField(FieldRefNum, ft.refNum[:]),
+               NewField(FieldWaitingCount, []byte{0x00, 0x00}), // TODO: Implement waiting count
+               NewField(FieldTransferSize, xferSize),
+               NewField(FieldFileSize, hlFile.ffo.FlatFileDataForkHeader.DataSize[:]),
         ))
  
         return res, err
         ))
  
         return res, err
@@ -1401,12 +1561,12 @@ func HandleDownloadFile(cc *ClientConn, t *Transaction) (res []Transaction, err
  
  // Download all files from the specified folder and sub-folders
  func HandleDownloadFolder(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  
  // Download all files from the specified folder and sub-folders
  func HandleDownloadFolder(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessDownloadFile) {
+       if !cc.Authorize(accessDownloadFile) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to download folders."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to download folders."))
                 return res, err
         }
  
-       fullFilePath, err := readPath(cc.Server.Config.FileRoot, t.GetField(fieldFilePath).Data, t.GetField(fieldFileName).Data)
+       fullFilePath, err := readPath(cc.Server.Config.FileRoot, t.GetField(FieldFilePath).Data, t.GetField(FieldFileName).Data)
         if err != nil {
                 return res, err
         }
         if err != nil {
                 return res, err
         }
@@ -1420,85 +1580,85 @@ func HandleDownloadFolder(cc *ClientConn, t *Transaction) (res []Transaction, er
                 return res, err
         }
  
                 return res, err
         }
  
-       fileTransfer := cc.newFileTransfer(FolderDownload, t.GetField(fieldFileName).Data, t.GetField(fieldFilePath).Data, transferSize)
+       fileTransfer := cc.newFileTransfer(FolderDownload, t.GetField(FieldFileName).Data, t.GetField(FieldFilePath).Data, transferSize)
  
         var fp FilePath
  
         var fp FilePath
-       err = fp.UnmarshalBinary(t.GetField(fieldFilePath).Data)
+       _, err = fp.Write(t.GetField(FieldFilePath).Data)
         if err != nil {
                 return res, err
         }
  
         res = append(res, cc.NewReply(t,
         if err != nil {
                 return res, err
         }
  
         res = append(res, cc.NewReply(t,
-               NewField(fieldRefNum, fileTransfer.ReferenceNumber),
-               NewField(fieldTransferSize, transferSize),
-               NewField(fieldFolderItemCount, itemCount),
-               NewField(fieldWaitingCount, []byte{0x00, 0x00}), // TODO: Implement waiting count
+               NewField(FieldRefNum, fileTransfer.ReferenceNumber),
+               NewField(FieldTransferSize, transferSize),
+               NewField(FieldFolderItemCount, itemCount),
+               NewField(FieldWaitingCount, []byte{0x00, 0x00}), // TODO: Implement waiting count
         ))
         return res, err
  }
  
  // Upload all files from the local folder and its subfolders to the specified path on the server
  // Fields used in the request
         ))
         return res, err
  }
  
  // Upload all files from the local folder and its subfolders to the specified path on the server
  // Fields used in the request
-// 201 File name
+// 201 File Name
  // 202 File path
  // 108 transfer size   Total size of all items in the folder
  // 220 Folder item count
  // 204 File transfer options   "Optional Currently set to 1" (TODO: ??)
  func HandleUploadFolder(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
         var fp FilePath
  // 202 File path
  // 108 transfer size   Total size of all items in the folder
  // 220 Folder item count
  // 204 File transfer options   "Optional Currently set to 1" (TODO: ??)
  func HandleUploadFolder(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
         var fp FilePath
-       if t.GetField(fieldFilePath).Data != nil {
-               if err = fp.UnmarshalBinary(t.GetField(fieldFilePath).Data); err != nil {
+       if t.GetField(FieldFilePath).Data != nil {
+               if _, err = fp.Write(t.GetField(FieldFilePath).Data); err != nil {
                         return res, err
                 }
         }
  
         // Handle special cases for Upload and Drop Box folders
                         return res, err
                 }
         }
  
         // Handle special cases for Upload and Drop Box folders
-       if !authorize(cc.Account.Access, accessUploadAnywhere) {
+       if !cc.Authorize(accessUploadAnywhere) {
                 if !fp.IsUploadDir() && !fp.IsDropbox() {
                 if !fp.IsUploadDir() && !fp.IsDropbox() {
-                       res = append(res, cc.NewErrReply(t, fmt.Sprintf("Cannot accept upload of the folder \"%v\" because you are only allowed to upload to the \"Uploads\" folder.", string(t.GetField(fieldFileName).Data))))
+                       res = append(res, cc.NewErrReply(t, fmt.Sprintf("Cannot accept upload of the folder \"%v\" because you are only allowed to upload to the \"Uploads\" folder.", string(t.GetField(FieldFileName).Data))))
                         return res, err
                 }
         }
  
         fileTransfer := cc.newFileTransfer(FolderUpload,
                         return res, err
                 }
         }
  
         fileTransfer := cc.newFileTransfer(FolderUpload,
-               t.GetField(fieldFileName).Data,
-               t.GetField(fieldFilePath).Data,
-               t.GetField(fieldTransferSize).Data,
+               t.GetField(FieldFileName).Data,
+               t.GetField(FieldFilePath).Data,
+               t.GetField(FieldTransferSize).Data,
         )
  
         )
  
-       fileTransfer.FolderItemCount = t.GetField(fieldFolderItemCount).Data
+       fileTransfer.FolderItemCount = t.GetField(FieldFolderItemCount).Data
  
  
-       res = append(res, cc.NewReply(t, NewField(fieldRefNum, fileTransfer.ReferenceNumber)))
+       res = append(res, cc.NewReply(t, NewField(FieldRefNum, fileTransfer.ReferenceNumber)))
         return res, err
  }
  
  // HandleUploadFile
  // Fields used in the request:
         return res, err
  }
  
  // HandleUploadFile
  // Fields used in the request:
-// 201 File name
+// 201 File Name
  // 202 File path
  // 204 File transfer options   "Optional
  // Used only to resume download, currently has value 2"
  // 108 File transfer size      "Optional used if download is not resumed"
  func HandleUploadFile(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // 202 File path
  // 204 File transfer options   "Optional
  // Used only to resume download, currently has value 2"
  // 108 File transfer size      "Optional used if download is not resumed"
  func HandleUploadFile(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessUploadFile) {
+       if !cc.Authorize(accessUploadFile) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to upload files."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to upload files."))
                 return res, err
         }
  
-       fileName := t.GetField(fieldFileName).Data
-       filePath := t.GetField(fieldFilePath).Data
-       transferOptions := t.GetField(fieldFileTransferOptions).Data
-       transferSize := t.GetField(fieldTransferSize).Data // not sent for resume
+       fileName := t.GetField(FieldFileName).Data
+       filePath := t.GetField(FieldFilePath).Data
+       transferOptions := t.GetField(FieldFileTransferOptions).Data
+       transferSize := t.GetField(FieldTransferSize).Data // not sent for resume
  
         var fp FilePath
         if filePath != nil {
  
         var fp FilePath
         if filePath != nil {
-               if err = fp.UnmarshalBinary(filePath); err != nil {
+               if _, err = fp.Write(filePath); err != nil {
                         return res, err
                 }
         }
  
         // Handle special cases for Upload and Drop Box folders
                         return res, err
                 }
         }
  
         // Handle special cases for Upload and Drop Box folders
-       if !authorize(cc.Account.Access, accessUploadAnywhere) {
+       if !cc.Authorize(accessUploadAnywhere) {
                 if !fp.IsUploadDir() && !fp.IsDropbox() {
                         res = append(res, cc.NewErrReply(t, fmt.Sprintf("Cannot accept upload of the file \"%v\" because you are only allowed to upload to the \"Uploads\" folder.", string(fileName))))
                         return res, err
                 if !fp.IsUploadDir() && !fp.IsDropbox() {
                         res = append(res, cc.NewErrReply(t, fmt.Sprintf("Cannot accept upload of the file \"%v\" because you are only allowed to upload to the \"Uploads\" folder.", string(fileName))))
                         return res, err
@@ -1510,17 +1670,16 @@ func HandleUploadFile(cc *ClientConn, t *Transaction) (res []Transaction, err er
         }
  
         if _, err := cc.Server.FS.Stat(fullFilePath); err == nil {
         }
  
         if _, err := cc.Server.FS.Stat(fullFilePath); err == nil {
-               res = append(res, cc.NewErrReply(t, fmt.Sprintf("Cannot accept upload because there is already a file named \"%v\".  Try choosing a different name.", string(fileName))))
+               res = append(res, cc.NewErrReply(t, fmt.Sprintf("Cannot accept upload because there is already a file named \"%v\".  Try choosing a different Name.", string(fileName))))
                 return res, err
         }
  
         ft := cc.newFileTransfer(FileUpload, fileName, filePath, transferSize)
  
                 return res, err
         }
  
         ft := cc.newFileTransfer(FileUpload, fileName, filePath, transferSize)
  
-       replyT := cc.NewReply(t, NewField(fieldRefNum, ft.ReferenceNumber))
+       replyT := cc.NewReply(t, NewField(FieldRefNum, ft.ReferenceNumber))
  
         // client has requested to resume a partially transferred file
         if transferOptions != nil {
  
         // client has requested to resume a partially transferred file
         if transferOptions != nil {
-
                 fileInfo, err := cc.Server.FS.Stat(fullFilePath + incompleteFileSuffix)
                 if err != nil {
                         return res, err
                 fileInfo, err := cc.Server.FS.Stat(fullFilePath + incompleteFileSuffix)
                 if err != nil {
                         return res, err
@@ -1537,7 +1696,7 @@ func HandleUploadFile(cc *ClientConn, t *Transaction) (res []Transaction, err er
  
                 ft.TransferSize = offset
  
  
                 ft.TransferSize = offset
  
-               replyT.Fields = append(replyT.Fields, NewField(fieldFileResumeData, b))
+               replyT.Fields = append(replyT.Fields, NewField(FieldFileResumeData, b))
         }
  
         res = append(res, replyT)
         }
  
         res = append(res, replyT)
@@ -1545,44 +1704,45 @@ func HandleUploadFile(cc *ClientConn, t *Transaction) (res []Transaction, err er
  }
  
  func HandleSetClientUserInfo(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleSetClientUserInfo(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       var icon []byte
-       if len(t.GetField(fieldUserIconID).Data) == 4 {
-               icon = t.GetField(fieldUserIconID).Data[2:]
+       if len(t.GetField(FieldUserIconID).Data) == 4 {
+               cc.Icon = t.GetField(FieldUserIconID).Data[2:]
         } else {
         } else {
-               icon = t.GetField(fieldUserIconID).Data
+               cc.Icon = t.GetField(FieldUserIconID).Data
+       }
+       if cc.Authorize(accessAnyName) {
+               cc.UserName = t.GetField(FieldUserName).Data
         }
         }
-       *cc.Icon = icon
-       cc.UserName = t.GetField(fieldUserName).Data
  
         // the options field is only passed by the client versions > 1.2.3.
  
         // the options field is only passed by the client versions > 1.2.3.
-       options := t.GetField(fieldOptions).Data
-
+       options := t.GetField(FieldOptions).Data
         if options != nil {
                 optBitmap := big.NewInt(int64(binary.BigEndian.Uint16(options)))
         if options != nil {
                 optBitmap := big.NewInt(int64(binary.BigEndian.Uint16(options)))
-               flagBitmap := big.NewInt(int64(binary.BigEndian.Uint16(*cc.Flags)))
+               flagBitmap := big.NewInt(int64(binary.BigEndian.Uint16(cc.Flags)))
  
  
-               flagBitmap.SetBit(flagBitmap, userFlagRefusePM, optBitmap.Bit(refusePM))
-               binary.BigEndian.PutUint16(*cc.Flags, uint16(flagBitmap.Int64()))
+               flagBitmap.SetBit(flagBitmap, UserFlagRefusePM, optBitmap.Bit(UserOptRefusePM))
+               binary.BigEndian.PutUint16(cc.Flags, uint16(flagBitmap.Int64()))
  
  
-               flagBitmap.SetBit(flagBitmap, userFLagRefusePChat, optBitmap.Bit(refuseChat))
-               binary.BigEndian.PutUint16(*cc.Flags, uint16(flagBitmap.Int64()))
+               flagBitmap.SetBit(flagBitmap, UserFlagRefusePChat, optBitmap.Bit(UserOptRefuseChat))
+               binary.BigEndian.PutUint16(cc.Flags, uint16(flagBitmap.Int64()))
  
                 // Check auto response
  
                 // Check auto response
-               if optBitmap.Bit(autoResponse) == 1 {
-                       cc.AutoReply = t.GetField(fieldAutomaticResponse).Data
+               if optBitmap.Bit(UserOptAutoResponse) == 1 {
+                       cc.AutoReply = t.GetField(FieldAutomaticResponse).Data
                 } else {
                         cc.AutoReply = []byte{}
                 }
         }
  
                 } else {
                         cc.AutoReply = []byte{}
                 }
         }
  
-       // Notify all clients of updated user info
-       cc.sendAll(
-               tranNotifyChangeUser,
-               NewField(fieldUserID, *cc.ID),
-               NewField(fieldUserIconID, *cc.Icon),
-               NewField(fieldUserFlags, *cc.Flags),
-               NewField(fieldUserName, cc.UserName),
-       )
+       for _, c := range sortedClients(cc.Server.Clients) {
+               res = append(res, *NewTransaction(
+                       TranNotifyChangeUser,
+                       c.ID,
+                       NewField(FieldUserID, *cc.ID),
+                       NewField(FieldUserIconID, cc.Icon),
+                       NewField(FieldUserFlags, cc.Flags),
+                       NewField(FieldUserName, cc.UserName),
+               ))
+       }
  
         return res, err
  }
  
         return res, err
  }
@@ -1599,29 +1759,29 @@ func HandleKeepAlive(cc *ClientConn, t *Transaction) (res []Transaction, err err
  func HandleGetFileNameList(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
         fullPath, err := readPath(
                 cc.Server.Config.FileRoot,
  func HandleGetFileNameList(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
         fullPath, err := readPath(
                 cc.Server.Config.FileRoot,
-               t.GetField(fieldFilePath).Data,
+               t.GetField(FieldFilePath).Data,
                 nil,
         )
         if err != nil {
                 nil,
         )
         if err != nil {
-               return res, err
+               return res, fmt.Errorf("error reading file path: %w", err)
         }
  
         var fp FilePath
         }
  
         var fp FilePath
-       if t.GetField(fieldFilePath).Data != nil {
-               if err = fp.UnmarshalBinary(t.GetField(fieldFilePath).Data); err != nil {
-                       return res, err
+       if t.GetField(FieldFilePath).Data != nil {
+               if _, err = fp.Write(t.GetField(FieldFilePath).Data); err != nil {
+                       return res, fmt.Errorf("error writing file path: %w", err)
                 }
         }
  
         // Handle special case for drop box folders
                 }
         }
  
         // Handle special case for drop box folders
-       if fp.IsDropbox() && !authorize(cc.Account.Access, accessViewDropBoxes) {
+       if fp.IsDropbox() && !cc.Authorize(accessViewDropBoxes) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to view drop boxes."))
                 return res, err
         }
  
                 res = append(res, cc.NewErrReply(t, "You are not allowed to view drop boxes."))
                 return res, err
         }
  
-       fileNames, err := getFileNameList(fullPath)
+       fileNames, err := getFileNameList(fullPath, cc.Server.Config.IgnoreFiles)
         if err != nil {
         if err != nil {
-               return res, err
+               return res, fmt.Errorf("getFileNameList: %w", err)
         }
  
         res = append(res, cc.NewReply(t, fileNames...))
         }
  
         res = append(res, cc.NewReply(t, fileNames...))
@@ -1632,43 +1792,61 @@ func HandleGetFileNameList(cc *ClientConn, t *Transaction) (res []Transaction, e
  // =================================
  //     Hotline private chat flow
  // =================================
  // =================================
  //     Hotline private chat flow
  // =================================
-// 1. ClientA sends tranInviteNewChat to server with user ID to invite
+// 1. ClientA sends TranInviteNewChat to server with user ID to invite
  // 2. Server creates new ChatID
  // 2. Server creates new ChatID
-// 3. Server sends tranInviteToChat to invitee
+// 3. Server sends TranInviteToChat to invitee
  // 4. Server replies to ClientA with new Chat ID
  //
  // A dialog box pops up in the invitee client with options to accept or decline the invitation.
  // If Accepted is clicked:
  // 4. Server replies to ClientA with new Chat ID
  //
  // A dialog box pops up in the invitee client with options to accept or decline the invitation.
  // If Accepted is clicked:
-// 1. ClientB sends tranJoinChat with fieldChatID
+// 1. ClientB sends TranJoinChat with FieldChatID
  
  // HandleInviteNewChat invites users to new private chat
  func HandleInviteNewChat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  
  // HandleInviteNewChat invites users to new private chat
  func HandleInviteNewChat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessOpenChat) {
+       if !cc.Authorize(accessOpenChat) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to request private chat."))
                 return res, err
         }
  
         // Client to Invite
                 res = append(res, cc.NewErrReply(t, "You are not allowed to request private chat."))
                 return res, err
         }
  
         // Client to Invite
-       targetID := t.GetField(fieldUserID).Data
+       targetID := t.GetField(FieldUserID).Data
         newChatID := cc.Server.NewPrivateChat(cc)
  
         newChatID := cc.Server.NewPrivateChat(cc)
  
-       res = append(res,
-               *NewTransaction(
-                       tranInviteToChat,
-                       &targetID,
-                       NewField(fieldChatID, newChatID),
-                       NewField(fieldUserName, cc.UserName),
-                       NewField(fieldUserID, *cc.ID),
-               ),
-       )
+       // Check if target user has "Refuse private chat" flag
+       binary.BigEndian.Uint16(targetID)
+       targetClient := cc.Server.Clients[binary.BigEndian.Uint16(targetID)]
+
+       flagBitmap := big.NewInt(int64(binary.BigEndian.Uint16(targetClient.Flags)))
+       if flagBitmap.Bit(UserFlagRefusePChat) == 1 {
+               res = append(res,
+                       *NewTransaction(
+                               TranServerMsg,
+                               cc.ID,
+                               NewField(FieldData, []byte(string(targetClient.UserName)+" does not accept private chats.")),
+                               NewField(FieldUserName, targetClient.UserName),
+                               NewField(FieldUserID, *targetClient.ID),
+                               NewField(FieldOptions, []byte{0, 2}),
+                       ),
+               )
+       } else {
+               res = append(res,
+                       *NewTransaction(
+                               TranInviteToChat,
+                               &targetID,
+                               NewField(FieldChatID, newChatID),
+                               NewField(FieldUserName, cc.UserName),
+                               NewField(FieldUserID, *cc.ID),
+                       ),
+               )
+       }
  
         res = append(res,
                 cc.NewReply(t,
  
         res = append(res,
                 cc.NewReply(t,
-                       NewField(fieldChatID, newChatID),
-                       NewField(fieldUserName, cc.UserName),
-                       NewField(fieldUserID, *cc.ID),
-                       NewField(fieldUserIconID, *cc.Icon),
-                       NewField(fieldUserFlags, *cc.Flags),
+                       NewField(FieldChatID, newChatID),
+                       NewField(FieldUserName, cc.UserName),
+                       NewField(FieldUserID, *cc.ID),
+                       NewField(FieldUserIconID, cc.Icon),
+                       NewField(FieldUserFlags, cc.Flags),
                 ),
         )
  
                 ),
         )
  
@@ -1676,32 +1854,32 @@ func HandleInviteNewChat(cc *ClientConn, t *Transaction) (res []Transaction, err
  }
  
  func HandleInviteToChat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleInviteToChat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessOpenChat) {
+       if !cc.Authorize(accessOpenChat) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to request private chat."))
                 return res, err
         }
  
         // Client to Invite
                 res = append(res, cc.NewErrReply(t, "You are not allowed to request private chat."))
                 return res, err
         }
  
         // Client to Invite
-       targetID := t.GetField(fieldUserID).Data
-       chatID := t.GetField(fieldChatID).Data
+       targetID := t.GetField(FieldUserID).Data
+       chatID := t.GetField(FieldChatID).Data
  
         res = append(res,
                 *NewTransaction(
  
         res = append(res,
                 *NewTransaction(
-                       tranInviteToChat,
+                       TranInviteToChat,
                         &targetID,
                         &targetID,
-                       NewField(fieldChatID, chatID),
-                       NewField(fieldUserName, cc.UserName),
-                       NewField(fieldUserID, *cc.ID),
+                       NewField(FieldChatID, chatID),
+                       NewField(FieldUserName, cc.UserName),
+                       NewField(FieldUserID, *cc.ID),
                 ),
         )
         res = append(res,
                 cc.NewReply(
                         t,
                 ),
         )
         res = append(res,
                 cc.NewReply(
                         t,
-                       NewField(fieldChatID, chatID),
-                       NewField(fieldUserName, cc.UserName),
-                       NewField(fieldUserID, *cc.ID),
-                       NewField(fieldUserIconID, *cc.Icon),
-                       NewField(fieldUserFlags, *cc.Flags),
+                       NewField(FieldChatID, chatID),
+                       NewField(FieldUserName, cc.UserName),
+                       NewField(FieldUserID, *cc.ID),
+                       NewField(FieldUserIconID, cc.Icon),
+                       NewField(FieldUserFlags, cc.Flags),
                 ),
         )
  
                 ),
         )
  
@@ -1709,7 +1887,7 @@ func HandleInviteToChat(cc *ClientConn, t *Transaction) (res []Transaction, err
  }
  
  func HandleRejectChatInvite(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  }
  
  func HandleRejectChatInvite(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       chatID := t.GetField(fieldChatID).Data
+       chatID := t.GetField(FieldChatID).Data
         chatInt := binary.BigEndian.Uint32(chatID)
  
         privChat := cc.Server.PrivateChats[chatInt]
         chatInt := binary.BigEndian.Uint32(chatID)
  
         privChat := cc.Server.PrivateChats[chatInt]
@@ -1719,10 +1897,10 @@ func HandleRejectChatInvite(cc *ClientConn, t *Transaction) (res []Transaction,
         for _, c := range sortedClients(privChat.ClientConn) {
                 res = append(res,
                         *NewTransaction(
         for _, c := range sortedClients(privChat.ClientConn) {
                 res = append(res,
                         *NewTransaction(
-                               tranChatMsg,
+                               TranChatMsg,
                                 c.ID,
                                 c.ID,
-                               NewField(fieldChatID, chatID),
-                               NewField(fieldData, resMsg),
+                               NewField(FieldChatID, chatID),
+                               NewField(FieldData, resMsg),
                         ),
                 )
         }
                         ),
                 )
         }
@@ -1733,41 +1911,43 @@ func HandleRejectChatInvite(cc *ClientConn, t *Transaction) (res []Transaction,
  // HandleJoinChat is sent from a v1.8+ Hotline client when the joins a private chat
  // Fields used in the reply:
  // * 115       Chat subject
  // HandleJoinChat is sent from a v1.8+ Hotline client when the joins a private chat
  // Fields used in the reply:
  // * 115       Chat subject
-// * 300       User name with info (Optional)
+// * 300       User Name with info (Optional)
  // * 300       (more user names with info)
  func HandleJoinChat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // * 300       (more user names with info)
  func HandleJoinChat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       chatID := t.GetField(fieldChatID).Data
+       chatID := t.GetField(FieldChatID).Data
         chatInt := binary.BigEndian.Uint32(chatID)
  
         privChat := cc.Server.PrivateChats[chatInt]
  
         chatInt := binary.BigEndian.Uint32(chatID)
  
         privChat := cc.Server.PrivateChats[chatInt]
  
-       // Send tranNotifyChatChangeUser to current members of the chat to inform of new user
+       // Send TranNotifyChatChangeUser to current members of the chat to inform of new user
         for _, c := range sortedClients(privChat.ClientConn) {
                 res = append(res,
                         *NewTransaction(
         for _, c := range sortedClients(privChat.ClientConn) {
                 res = append(res,
                         *NewTransaction(
-                               tranNotifyChatChangeUser,
+                               TranNotifyChatChangeUser,
                                 c.ID,
                                 c.ID,
-                               NewField(fieldChatID, chatID),
-                               NewField(fieldUserName, cc.UserName),
-                               NewField(fieldUserID, *cc.ID),
-                               NewField(fieldUserIconID, *cc.Icon),
-                               NewField(fieldUserFlags, *cc.Flags),
+                               NewField(FieldChatID, chatID),
+                               NewField(FieldUserName, cc.UserName),
+                               NewField(FieldUserID, *cc.ID),
+                               NewField(FieldUserIconID, cc.Icon),
+                               NewField(FieldUserFlags, cc.Flags),
                         ),
                 )
         }
  
         privChat.ClientConn[cc.uint16ID()] = cc
  
                         ),
                 )
         }
  
         privChat.ClientConn[cc.uint16ID()] = cc
  
-       replyFields := []Field{NewField(fieldChatSubject, []byte(privChat.Subject))}
+       replyFields := []Field{NewField(FieldChatSubject, []byte(privChat.Subject))}
         for _, c := range sortedClients(privChat.ClientConn) {
         for _, c := range sortedClients(privChat.ClientConn) {
-               user := User{
+               b, err := io.ReadAll(&User{
                         ID:    *c.ID,
                         ID:    *c.ID,
-                       Icon:  *c.Icon,
-                       Flags: *c.Flags,
+                       Icon:  c.Icon,
+                       Flags: c.Flags,
                         Name:  string(c.UserName),
                         Name:  string(c.UserName),
+               })
+               if err != nil {
+                       return res, nil
                 }
                 }
-
-               replyFields = append(replyFields, NewField(fieldUsernameWithInfo, user.Payload()))
+               replyFields = append(replyFields, NewField(FieldUsernameWithInfo, b))
         }
  
         res = append(res, cc.NewReply(t, replyFields...))
         }
  
         res = append(res, cc.NewReply(t, replyFields...))
@@ -1776,13 +1956,17 @@ func HandleJoinChat(cc *ClientConn, t *Transaction) (res []Transaction, err erro
  
  // HandleLeaveChat is sent from a v1.8+ Hotline client when the user exits a private chat
  // Fields used in the request:
  
  // HandleLeaveChat is sent from a v1.8+ Hotline client when the user exits a private chat
  // Fields used in the request:
-//     * 114   fieldChatID
+//   - 114     FieldChatID
+//
  // Reply is not expected.
  func HandleLeaveChat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // Reply is not expected.
  func HandleLeaveChat(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       chatID := t.GetField(fieldChatID).Data
+       chatID := t.GetField(FieldChatID).Data
         chatInt := binary.BigEndian.Uint32(chatID)
  
         chatInt := binary.BigEndian.Uint32(chatID)
  
-       privChat := cc.Server.PrivateChats[chatInt]
+       privChat, ok := cc.Server.PrivateChats[chatInt]
+       if !ok {
+               return res, nil
+       }
  
         delete(privChat.ClientConn, cc.uint16ID())
  
  
         delete(privChat.ClientConn, cc.uint16ID())
  
@@ -1790,10 +1974,10 @@ func HandleLeaveChat(cc *ClientConn, t *Transaction) (res []Transaction, err err
         for _, c := range sortedClients(privChat.ClientConn) {
                 res = append(res,
                         *NewTransaction(
         for _, c := range sortedClients(privChat.ClientConn) {
                 res = append(res,
                         *NewTransaction(
-                               tranNotifyChatDeleteUser,
+                               TranNotifyChatDeleteUser,
                                 c.ID,
                                 c.ID,
-                               NewField(fieldChatID, chatID),
-                               NewField(fieldUserID, *cc.ID),
+                               NewField(FieldChatID, chatID),
+                               NewField(FieldUserID, *cc.ID),
                         ),
                 )
         }
                         ),
                 )
         }
@@ -1804,22 +1988,22 @@ func HandleLeaveChat(cc *ClientConn, t *Transaction) (res []Transaction, err err
  // HandleSetChatSubject is sent from a v1.8+ Hotline client when the user sets a private chat subject
  // Fields used in the request:
  // * 114       Chat ID
  // HandleSetChatSubject is sent from a v1.8+ Hotline client when the user sets a private chat subject
  // Fields used in the request:
  // * 114       Chat ID
-// * 115       Chat subject    Chat subject string
+// * 115       Chat subject
  // Reply is not expected.
  func HandleSetChatSubject(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // Reply is not expected.
  func HandleSetChatSubject(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       chatID := t.GetField(fieldChatID).Data
+       chatID := t.GetField(FieldChatID).Data
         chatInt := binary.BigEndian.Uint32(chatID)
  
         privChat := cc.Server.PrivateChats[chatInt]
         chatInt := binary.BigEndian.Uint32(chatID)
  
         privChat := cc.Server.PrivateChats[chatInt]
-       privChat.Subject = string(t.GetField(fieldChatSubject).Data)
+       privChat.Subject = string(t.GetField(FieldChatSubject).Data)
  
         for _, c := range sortedClients(privChat.ClientConn) {
                 res = append(res,
                         *NewTransaction(
  
         for _, c := range sortedClients(privChat.ClientConn) {
                 res = append(res,
                         *NewTransaction(
-                               tranNotifyChatSubject,
+                               TranNotifyChatSubject,
                                 c.ID,
                                 c.ID,
-                               NewField(fieldChatID, chatID),
-                               NewField(fieldChatSubject, t.GetField(fieldChatSubject).Data),
+                               NewField(FieldChatID, chatID),
+                               NewField(FieldChatSubject, t.GetField(FieldChatSubject).Data),
                         ),
                 )
         }
                         ),
                 )
         }
@@ -1827,22 +2011,22 @@ func HandleSetChatSubject(cc *ClientConn, t *Transaction) (res []Transaction, er
         return res, err
  }
  
         return res, err
  }
  
-// HandleMakeAlias makes a filer alias using the specified path.
+// HandleMakeAlias makes a file alias using the specified path.
  // Fields used in the request:
  // Fields used in the request:
-// 201 File name
+// 201 File Name
  // 202 File path
  // 212 File new path   Destination path
  //
  // Fields used in the reply:
  // None
  func HandleMakeAlias(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  // 202 File path
  // 212 File new path   Destination path
  //
  // Fields used in the reply:
  // None
  func HandleMakeAlias(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       if !authorize(cc.Account.Access, accessMakeAlias) {
+       if !cc.Authorize(accessMakeAlias) {
                 res = append(res, cc.NewErrReply(t, "You are not allowed to make aliases."))
                 return res, err
         }
                 res = append(res, cc.NewErrReply(t, "You are not allowed to make aliases."))
                 return res, err
         }
-       fileName := t.GetField(fieldFileName).Data
-       filePath := t.GetField(fieldFilePath).Data
-       fileNewPath := t.GetField(fieldFileNewPath).Data
+       fileName := t.GetField(FieldFileName).Data
+       filePath := t.GetField(FieldFilePath).Data
+       fileNewPath := t.GetField(FieldFileNewPath).Data
  
         fullFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, fileName)
         if err != nil {
  
         fullFilePath, err := readPath(cc.Server.Config.FileRoot, filePath, fileName)
         if err != nil {
@@ -1854,7 +2038,7 @@ func HandleMakeAlias(cc *ClientConn, t *Transaction) (res []Transaction, err err
                 return res, err
         }
  
                 return res, err
         }
  
-       cc.logger.Debugw("Make alias", "src", fullFilePath, "dst", fullNewFilePath)
+       cc.logger.Debug("Make alias", "src", fullFilePath, "dst", fullNewFilePath)
  
         if err := cc.Server.FS.Symlink(fullFilePath, fullNewFilePath); err != nil {
                 res = append(res, cc.NewErrReply(t, "Error creating alias"))
  
         if err := cc.Server.FS.Symlink(fullFilePath, fullNewFilePath); err != nil {
                 res = append(res, cc.NewErrReply(t, "Error creating alias"))
@@ -1865,20 +2049,18 @@ func HandleMakeAlias(cc *ClientConn, t *Transaction) (res []Transaction, err err
         return res, err
  }
  
         return res, err
  }
  
+// HandleDownloadBanner handles requests for a new banner from the server
+// Fields used in the request:
+// None
+// Fields used in the reply:
+// 107 FieldRefNum                     Used later for transfer
+// 108 FieldTransferSize       Size of data to be downloaded
  func HandleDownloadBanner(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
  func HandleDownloadBanner(cc *ClientConn, t *Transaction) (res []Transaction, err error) {
-       fi, err := cc.Server.FS.Stat(filepath.Join(cc.Server.ConfigDir, cc.Server.Config.BannerFile))
-       if err != nil {
-               return res, err
-       }
-
         ft := cc.newFileTransfer(bannerDownload, []byte{}, []byte{}, make([]byte, 4))
         ft := cc.newFileTransfer(bannerDownload, []byte{}, []byte{}, make([]byte, 4))
+       binary.BigEndian.PutUint32(ft.TransferSize, uint32(len(cc.Server.banner)))
  
  
-       binary.BigEndian.PutUint32(ft.TransferSize, uint32(fi.Size()))
-
-       res = append(res, cc.NewReply(t,
-               NewField(fieldRefNum, ft.refNum[:]),
-               NewField(fieldTransferSize, ft.TransferSize),
-       ))
-
-       return res, err
+       return append(res, cc.NewReply(t,
+               NewField(FieldRefNum, ft.refNum[:]),
+               NewField(FieldTransferSize, ft.TransferSize),
+       )), err
  }
  }