Support individual channel keys for pre-defined channels.

This patch introduces the new configuration variable "KeyFile" for
[Channel] sections in ngircd.conf. Here a file can be configured for each
pre-defined channel which contains individual channel keys for different
users. This file is line-based and must have the following syntax:

  <user>:<nick>:<key>

<user> and <nick> can contain the wildcard character "*".

Please not that these channel keys are only in effect, when the channel
has a regular key set using channel mode "k"!

doc/sample-ngircd.conf

@@ -245,6 +245,10 @@
 	# initial channel password (mode k)
 	;Key = Secret
 
+	# Key file, syntax for each line: "<user>:<nick>:<key>".
+	# Default: none.
+	;KeyFile = /etc/ngircd/#chan.key
+
 	# maximum users per channel (mode l)
 	;MaxUsers = 23
 

man/ngircd.conf.5.tmpl

@@ -319,7 +319,50 @@ Topic for this channel.
 Initial channel modes.
 .TP
 \fBKey\fR
-Sets initial channel key (only relevant if mode k is set).
+Sets initial channel key (only relevant if channel mode "k" is set).
+.TP
+\fBKeyFile\fR
+Path and file name of a "key file" containing individual channel keys for
+different users. The file consists of plain text lines with the following
+syntax (without spaces!):
+.PP
+.RS
+.RS
+.I user
+:
+.I nick
+:
+.I key
+.RE
+.PP
+.I user
+and
+.I nick
+can contain the wildcard character "*".
+.br
+.I key
+is an arbitrary password.
+.PP
+Valid examples are:
+.PP
+.RS
+*:*:KeY
+.br
+*:nick:123
+.br
+~user:*:xyz
+.RE
+.PP
+The key file is read on each JOIN command when this channel has a key
+(channel mode +k). Access is granted, if a) the channel key set using the
+MODE +k command or b) one of the lines in the key file match.
+.PP
+.B Please note:
+.br
+The file is not reopened on each access, so you can modify and overwrite it
+without problems, but moving or deleting the file will have not effect until
+the daemon re-reads its configuration!
+.RE
 .TP
 \fBMaxUsers\fR
 Set maximum user limit for this channel (only relevant if channel mode "l"

src/ngircd/channel.c

@@ -22,6 +22,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
+#include <stdio.h>
 #include <strings.h>
 
 #include "defines.h"
@@ -39,6 +40,7 @@
 #include "lists.h"
 #include "log.h"
 #include "messages.h"
+#include "match.h"
 
 #include "exp.h"
 
@@ -59,6 +61,9 @@ static CL2CHAN *Get_First_Cl2Chan PARAMS(( CLIENT *Client, CHANNEL *Chan ));
 static CL2CHAN *Get_Next_Cl2Chan PARAMS(( CL2CHAN *Start, CLIENT *Client, CHANNEL *Chan ));
 static void Delete_Channel PARAMS(( CHANNEL *Chan ));
 static void Free_Channel PARAMS(( CHANNEL *Chan ));
+static void Update_Predefined PARAMS((CHANNEL *Chan,
+				      const struct Conf_Channel *Conf_Chan));
+static void Set_Key_File PARAMS((CHANNEL *Chan, FILE *KeyFile));
 
 
 GLOBAL void
@@ -116,8 +121,10 @@ Channel_InitPredefined( void )
 
 		new_chan = Channel_Search(conf_chan->name);
 		if (new_chan) {
-			Log(LOG_INFO, "Can't create pre-defined channel \"%s\": name already in use.",
+			Log(LOG_INFO,
-										conf_chan->name);
+			    "Can't create pre-defined channel \"%s\": name already in use.",
+			    conf_chan->name);
+			Update_Predefined(new_chan, conf_chan);
 			continue;
 		}
 
@@ -127,6 +134,8 @@ Channel_InitPredefined( void )
 							conf_chan->name);
 			continue;
 		}
+		Log(LOG_INFO, "Created pre-defined channel \"%s\"",
+						conf_chan->name);
 
 		Channel_ModeAdd(new_chan, 'P');
 
@@ -139,8 +148,7 @@ Channel_InitPredefined( void )
 
 		Channel_SetKey(new_chan, conf_chan->key);
 		Channel_SetMaxUsers(new_chan, conf_chan->maxusers);
-		Log(LOG_INFO, "Created pre-defined channel \"%s\"",
+		Update_Predefined(new_chan, conf_chan);
-						conf_chan->name);
 	}
 	if (channel_count)
 		array_free(&Conf_Channels);
@@ -153,6 +161,8 @@ Free_Channel(CHANNEL *chan)
 	array_free(&chan->topic);
 	Lists_Free(&chan->list_bans);
 	Lists_Free(&chan->list_invites);
+	if (Chan->keyfile)
+		fclose(Chan->keyfile);
 
 	free(chan);
 }
@@ -1051,6 +1061,44 @@ Channel_LogServer(char *msg)
 } /* Channel_LogServer */
 
 
+GLOBAL bool
+Channel_CheckKey(CHANNEL *Chan, CLIENT *Client, const char *Key)
+{
+	char line[COMMAND_LEN], *nick, *pass;
+
+	assert(Chan != NULL);
+	assert(Client != NULL);
+	assert(Key != NULL);
+
+	if (!strchr(Chan->modes, 'k'))
+		return true;
+	if (strcmp(Chan->key, Key) == 0)
+		return true;
+	if (!Chan->keyfile)
+		return false;
+
+	Chan->keyfile = freopen(NULL, "r", Chan->keyfile);
+	while (fgets(line, sizeof(line), Chan->keyfile) != NULL) {
+		ngt_TrimStr(line);
+		if (! (nick = strchr(line, ':')))
+			continue;
+		*nick++ = '\0';
+		if (!Match(line, Client_User(Client)))
+			continue;
+		if (! (pass = strchr(nick, ':')))
+			continue;
+		*pass++ = '\0';
+		if (!Match(nick, Client_ID(Client)))
+			continue;
+		if (strcmp(Key, pass) != 0)
+			continue;
+
+		return true;
+	}
+	return false;
+} /* Channel_CheckKey */
+
+
 static CL2CHAN *
 Get_First_Cl2Chan( CLIENT *Client, CHANNEL *Chan )
 {
@@ -1108,4 +1156,36 @@ Delete_Channel(CHANNEL *Chan)
 } /* Delete_Channel */
 
 
+static void
+Update_Predefined(CHANNEL *Chan, const struct Conf_Channel *Conf_Chan)
+{
+	FILE *fd;
+
+	if (! Conf_Chan->keyfile || ! *Conf_Chan->keyfile)
+		return;
+
+	fd = fopen(Conf_Chan->keyfile, "r");
+	if (! fd)
+		Log(LOG_ERR,
+		    "Can't open channel key file for \"%s\", \"%s\": %s",
+		    Conf_Chan->name, Conf_Chan->keyfile,
+		    strerror(errno));
+	else
+		Set_Key_File(Chan, fd);
+} /* Update_Predefined */
+
+
+static void
+Set_Key_File(CHANNEL *Chan, FILE *KeyFile)
+{
+	assert(Chan != NULL);
+
+	if (Chan->keyfile)
+		fclose(Chan->keyfile);
+	Chan->keyfile = KeyFile;
+	Log(LOG_INFO|LOG_snotice,
+	    "New local channel key file for \"%s\" activated.", Chan->name);
+} /* Set_Key_File */
+
+
 /* -eof- */

src/ngircd/channel.h

@@ -37,6 +37,7 @@ typedef struct _CHANNEL
 	unsigned long maxusers;		/* Maximum number of members (mode "l") */
 	struct list_head list_bans;	/* list head of banned users */
 	struct list_head list_invites;	/* list head of invited users */
+	FILE *keyfile;			/* handle of the channel key file */
 } CHANNEL;
 
 typedef struct _CLIENT2CHAN
@@ -127,6 +128,9 @@ GLOBAL bool Channel_ShowInvites PARAMS((CLIENT *client, CHANNEL *c));
 
 GLOBAL void Channel_LogServer PARAMS((char *msg));
 
+GLOBAL bool Channel_CheckKey PARAMS((CHANNEL *Chan, CLIENT *Client,
+				     const char *Key));
+
 #define Channel_IsLocal(c) (Channel_Name(c)[0] == '&')
 
 

src/ngircd/conf.c

@@ -313,7 +313,8 @@ Conf_Test( void )
 		printf("  Modes = %s\n", predef_chan->modes);
 		printf("  Key = %s\n", predef_chan->key);
 		printf("  MaxUsers = %lu\n", predef_chan->maxusers);
-		printf("  Topic = %s\n\n", predef_chan->topic);
+		printf("  Topic = %s\n", predef_chan->topic);
+		printf("  KeyFile = %s\n\n", predef_chan->keyfile);
 	}
 
 	return (config_valid ? 0 : 1);
@@ -1232,6 +1233,13 @@ Handle_CHANNEL(int Line, char *Var, char *Arg)
 			Config_Error_NaN(Line, Var);
 		return;
 	}
+	if (strcasecmp(Var, "KeyFile") == 0) {
+		/* channel keys */
+		len = strlcpy(chan->keyfile, Arg, sizeof(chan->keyfile));
+		if (len >= sizeof(chan->keyfile))
+			Config_Error_TooLong(Line, Var);
+		return;
+	}
 
 	Config_Error( LOG_ERR, "%s, line %d (section \"Channel\"): Unknown variable \"%s\"!",
 								NGIRCd_ConfFile, Line, Var );

src/ngircd/conf.h

@@ -72,6 +72,7 @@ struct Conf_Channel {
 	char modes[CHANNEL_MODE_LEN];	/* Initial channel modes */
 	char key[CLIENT_PASS_LEN];      /* Channel key ("password", mode "k" ) */
 	char topic[COMMAND_LEN];	/* Initial topic */
+	char keyfile[512];		/* Path and name of channel key file */
 	unsigned long maxusers;		/* maximum usercount for this channel, mode "l" */
 };
 

src/ngircd/irc-channel.c

@@ -89,10 +89,9 @@ join_allowed(CLIENT *Client, CLIENT *target, CHANNEL *chan,
 	}
 
 	/* Is the channel protected by a key? */
-	if (strchr(channel_modes, 'k') &&
+	if (!Channel_CheckKey(chan, target, key ? key : "")) {
-		strcmp(Channel_Key(chan), key ? key : ""))
+		IRC_WriteStrClient(Client, ERR_BADCHANNELKEY_MSG,
-	{
+				   Client_ID(Client), channame);
-		IRC_WriteStrClient(Client, ERR_BADCHANNELKEY_MSG, Client_ID(Client), channame);
 		return false;
 	}
 	/* Are there already too many members? */