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package hotline
import (
"encoding/binary"
)
// User flags are stored as a 2 byte bitmap with the following values:
const (
userFlagAway = 0 // User is away
userFlagAdmin = 1 // User is admin
userFlagRefusePM = 2 // User refuses private messages
userFLagRefusePChat = 3 // User refuses private chat
)
// fieldOptions flags are sent from v1.5+ clients as part of tranAgreed
const (
refusePM = 0 // User has "Refuse private messages" pref set
refuseChat = 1 // User has "Refuse private chat" pref set
autoResponse = 2 // User has "Automatic response" pref set
)
type User struct {
ID []byte // Size 2
Icon []byte // Size 2
Flags []byte // Size 2
Name string // Variable length user name
}
func (u User) Payload() []byte {
nameLen := make([]byte, 2)
binary.BigEndian.PutUint16(nameLen, uint16(len(u.Name)))
if len(u.Icon) == 4 {
u.Icon = u.Icon[2:]
}
if len(u.Flags) == 4 {
u.Flags = u.Flags[2:]
}
out := append(u.ID[:2], u.Icon[:2]...)
out = append(out, u.Flags[:2]...)
out = append(out, nameLen...)
out = append(out, u.Name...)
return out
}
func ReadUser(b []byte) (*User, error) {
u := &User{
ID: b[0:2],
Icon: b[2:4],
Flags: b[4:6],
Name: string(b[8:]),
}
return u, nil
}
// DecodeUserString decodes an obfuscated user string from a client
// e.g. 98 8a 9a 8c 8b => "guest"
func DecodeUserString(obfuText []byte) (clearText string) {
for _, char := range obfuText {
clearText += string(rune(255 - uint(char)))
}
return clearText
}
// negateString takes []byte s containing cleartext and rotates by 255 into obfuscated cleartext.
// The Hotline protocol uses this format for sending passwords over network.
// Not secure, but hey, it was the 90s!
func negateString(clearText []byte) []byte {
obfuText := make([]byte, len(clearText))
for i := 0; i < len(clearText); i++ {
obfuText[i] = 255 - clearText[i]
}
return obfuText
}
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