Improve Frogblast client compatibility

3 files changed, 67 insertions, 3 deletions

diff --git a/hotline/server.go b/hotline/server.go
index ec83522..8d6803b 100644
--- a/hotline/server.go
+++ b/hotline/server.go
@@ -34,6 +34,7 @@ type requestCtx struct {
 }
 
 var nostalgiaVersion = []byte{0, 0, 2, 0x2c} // version ID used by the Nostalgia client
+var frogblastVersion = []byte{0, 0, 0, 0xb9} // version ID used by the Frogblast 1.2.4 client
 
 type Server struct {
 	Port          int
@@ -667,7 +668,7 @@ func (s *Server) handleNewConnection(ctx context.Context, rwc io.ReadWriteCloser
 	}
 
 	// Used simplified hotline v1.2.3 login flow for clients that do not send login info in tranAgreed
-	if c.Version == nil || bytes.Equal(c.Version, nostalgiaVersion) {
+	if c.Version == nil || bytes.Equal(c.Version, nostalgiaVersion) || bytes.Equal(c.Version, frogblastVersion) {
 		c.Agreed = true
 		c.logger = c.logger.With("name", string(c.UserName))
 		c.logger.Infow("Login successful", "clientVersion", fmt.Sprintf("%v", func() int { i, _ := byteToInt(c.Version); return i }()))
diff --git a/hotline/transaction_handlers.go b/hotline/transaction_handlers.go
index 5a9ea5e..6816456 100644
--- a/hotline/transaction_handlers.go
+++ b/hotline/transaction_handlers.go
@@ -253,9 +253,10 @@ func HandleChatSend(cc *ClientConn, t *Transaction) (res []Transaction, err erro
 		formattedMsg = fmt.Sprintf("\r*** %s %s", cc.UserName, t.GetField(fieldData).Data)
 	}
 
+	// 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
-	// a non-nil chatID indicates the message belongs to a private chat
-	if chatID != nil {
+	if chatID != nil && !bytes.Equal([]byte{0, 0, 0, 0}, chatID) {
 		chatInt := binary.BigEndian.Uint32(chatID)
 		privChat := cc.Server.PrivateChats[chatInt]
 
diff --git a/hotline/transaction_handlers_test.go b/hotline/transaction_handlers_test.go
index bc40254..8898594 100644
--- a/hotline/transaction_handlers_test.go
+++ b/hotline/transaction_handlers_test.go
@@ -364,6 +364,68 @@ func TestHandleChatSend(t *testing.T) {
 			wantErr: false,
 		},
 		{
+			name: "treats Chat ID 00 00 00 00 as a public chat message",
+			args: args{
+				cc: &ClientConn{
+					Account: &Account{
+						Access: func() accessBitmap {
+							var bits accessBitmap
+							bits.Set(accessSendChat)
+							return bits
+						}(),
+					},
+					UserName: []byte{0x00, 0x01},
+					Server: &Server{
+						Clients: map[uint16]*ClientConn{
+							uint16(1): {
+								Account: &Account{
+									Access: accessBitmap{255, 255, 255, 255, 255, 255, 255, 255},
+								},
+								ID: &[]byte{0, 1},
+							},
+							uint16(2): {
+								Account: &Account{
+									Access: accessBitmap{255, 255, 255, 255, 255, 255, 255, 255},
+								},
+								ID: &[]byte{0, 2},
+							},
+						},
+					},
+				},
+				t: &Transaction{
+					Fields: []Field{
+						NewField(fieldData, []byte("hai")),
+						NewField(fieldChatID, []byte{0, 0, 0, 0}),
+					},
+				},
+			},
+			want: []Transaction{
+				{
+					clientID:  &[]byte{0, 1},
+					Flags:     0x00,
+					IsReply:   0x00,
+					Type:      []byte{0, 0x6a},
+					ID:        []byte{0x9a, 0xcb, 0x04, 0x42}, // Random ID from rand.Seed(1)
+					ErrorCode: []byte{0, 0, 0, 0},
+					Fields: []Field{
+						NewField(fieldData, []byte{0x0d, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x00, 0x01, 0x3a, 0x20, 0x20, 0x68, 0x61, 0x69}),
+					},
+				},
+				{
+					clientID:  &[]byte{0, 2},
+					Flags:     0x00,
+					IsReply:   0x00,
+					Type:      []byte{0, 0x6a},
+					ID:        []byte{0xf0, 0xc5, 0x34, 0x1e}, // Random ID from rand.Seed(1)
+					ErrorCode: []byte{0, 0, 0, 0},
+					Fields: []Field{
+						NewField(fieldData, []byte{0x0d, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x00, 0x01, 0x3a, 0x20, 0x20, 0x68, 0x61, 0x69}),
+					},
+				},
+			},
+			wantErr: false,
+		},
+		{
 			name: "when user does not have required permission",
 			args: args{
 				cc: &ClientConn{