X-Git-Url: https://arthur.barton.de/cgi-bin/gitweb.cgi?p=ngircd-alex.git;a=blobdiff_plain;f=src%2Fngircd%2Firc-login.c;h=92d54ab15e42ad64d2e7d05bd605bccc1cd7f734;hp=62e339769fcf2382293bc1dac59f643dcc11f4f9;hb=fa8b83e69b0d7edcfdcf8f0a4496c79f9c5ec161;hpb=e56bd8ff89b224ba9d78dee69587643be909605b

diff --git a/src/ngircd/irc-login.c b/src/ngircd/irc-login.c
index 62e33976..92d54ab1 100644
--- a/src/ngircd/irc-login.c
+++ b/src/ngircd/irc-login.c
@@ -1,34 +1,38 @@
 /*
  * ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001-2008 Alexander Barton (alex@barton.de)
+ * Copyright (c)2001-2010 Alexander Barton (alex@barton.de)
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  * Please read the file COPYING, README and AUTHORS for more information.
- *
- * Login and logout
  */
 
-
 #include "portab.h"
 
+/**
+ * @file
+ * Login and logout
+ */
+
 #include "imp.h"
 #include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <strings.h>
+#include <signal.h>
+#include <unistd.h>
 
 #include "ngircd.h"
-#include "resolve.h"
 #include "conn-func.h"
 #include "conf.h"
-#include "client.h"
 #include "channel.h"
+#include "io.h"
 #include "log.h"
 #include "messages.h"
+#include "pam.h"
 #include "parse.h"
 #include "irc.h"
 #include "irc-info.h"
@@ -39,12 +43,26 @@
 
 
 static bool Hello_User PARAMS(( CLIENT *Client ));
+static bool Hello_User_PostAuth PARAMS(( CLIENT *Client ));
 static void Kill_Nick PARAMS(( char *Nick, char *Reason ));
+static void Introduce_Client PARAMS((CLIENT *To, CLIENT *Client, int Type));
+static void Reject_Client PARAMS((CLIENT *Client));
+
+static void cb_introduceClient PARAMS((CLIENT *Client, CLIENT *Prefix,
+				       void *i));
 
+#ifdef PAM
+static void cb_Read_Auth_Result PARAMS((int r_fd, UNUSED short events));
+#endif
 
 /**
- * Handler for the IRC command "PASS".
+ * Handler for the IRC "PASS" command.
+ *
  * See RFC 2813 section 4.1.1, and RFC 2812 section 3.1.1.
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED.
  */
 GLOBAL bool
 IRC_PASS( CLIENT *Client, REQUEST *Req )
@@ -64,7 +82,7 @@ IRC_PASS( CLIENT *Client, REQUEST *Req )
 		/* Not yet registered "unknown" connection, PASS with one
 		 * argument: either a regular client, service, or server
 		 * using the old RFC 1459 section 4.1.1 syntax. */
-		LogDebug("Connection %d: got PASS command ...",
+		LogDebug("Connection %d: got PASS command (RFC 1459) ...",
 			 Client_Conn(Client));
 	} else if ((Client_Type(Client) == CLIENT_UNKNOWN ||
 		    Client_Type(Client) == CLIENT_UNKNOWNSERVER) &&
@@ -72,7 +90,7 @@ IRC_PASS( CLIENT *Client, REQUEST *Req )
 		/* Not yet registered "unknown" connection or outgoing server
 		 * link, PASS with three or four argument: server using the
 		 * RFC 2813 section 4.1.1 syntax. */
-		LogDebug("Connection %d: got PASS command (new server link) ...",
+		LogDebug("Connection %d: got PASS command (RFC 2813, new server link) ...",
 			 Client_Conn(Client));
 	} else if (Client_Type(Client) == CLIENT_UNKNOWN ||
 		   Client_Type(Client) == CLIENT_UNKNOWNSERVER) {
@@ -86,7 +104,6 @@ IRC_PASS( CLIENT *Client, REQUEST *Req )
 	}
 
 	Client_SetPassword(Client, Req->argv[0]);
-	Client_SetType(Client, CLIENT_GOTPASS);
 
 	/* Protocol version */
 	if (Req->argc >= 2 && strlen(Req->argv[1]) >= 4) {
@@ -102,8 +119,12 @@ IRC_PASS( CLIENT *Client, REQUEST *Req )
 
 		Req->argv[1][2] = c2;
 		Req->argv[1][4] = c4;
-	} else
+
+		Client_SetType(Client, CLIENT_GOTPASS_2813);
+	} else {
 		protohigh = protolow = 0;
+		Client_SetType(Client, CLIENT_GOTPASS);
+	}
 
 	/* Protocol type, see doc/Protocol.txt */
 	if (Req->argc >= 2 && strlen(Req->argv[1]) > 4)
@@ -129,27 +150,28 @@ IRC_PASS( CLIENT *Client, REQUEST *Req )
 		if (type && strcmp(type, PROTOIRCPLUS) == 0) {
 			/* The peer seems to be a server which supports the
 			 * IRC+ protocol (see doc/Protocol.txt). */
-			serverver = ptr + 1;
-			flags = strchr(serverver, ':');
+			serverver = ptr ? ptr + 1 : "?";
+			flags = strchr(ptr ? serverver : impl, ':');
 			if (flags) {
 				*flags = '\0';
 				flags++;
 			} else
 				flags = "";
 			Log(LOG_INFO,
-			    "Peer announces itself as %s-%s using protocol %d.%d/IRC+ (flags: \"%s\").",
-			    impl, serverver, protohigh, protolow, flags);
+			    "Peer on conenction %d announces itself as %s-%s using protocol %d.%d/IRC+ (flags: \"%s\").",
+			    Client_Conn(Client), impl, serverver,
+			    protohigh, protolow, flags);
 		} else {
 			/* The peer seems to be a server supporting the
 			 * "original" IRC protocol (RFC 2813). */
-			serverver = "";
 			if (strchr(orig_flags, 'Z'))
 				flags = "Z";
 			else
 				flags = "";
 			Log(LOG_INFO,
-			    "Peer announces itself as \"%s\" using protocol %d.%d (flags: \"%s\").",
-			    impl, protohigh, protolow, flags);
+			    "Peer on connection %d announces itself as \"%s\" using protocol %d.%d (flags: \"%s\").",
+			    Client_Conn(Client), impl,
+			    protohigh, protolow, flags);
 		}
 		Client_SetFlags(Client, flags);
 	}
@@ -159,36 +181,39 @@ IRC_PASS( CLIENT *Client, REQUEST *Req )
 
 
 /**
- * IRC "NICK" command.
+ * Handler for the IRC "NICK" command.
+ *
+ * See RFC 2812, 3.1.2 "Nick message", and RFC 2813, 4.1.3 "Nick".
+ *
  * This function implements the IRC command "NICK" which is used to register
  * with the server, to change already registered nicknames and to introduce
  * new users which are connected to other servers.
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED.
  */
 GLOBAL bool
 IRC_NICK( CLIENT *Client, REQUEST *Req )
 {
 	CLIENT *intr_c, *target, *c;
-	char *modes;
+	char *nick, *user, *hostname, *modes, *info;
+	int token, hops;
 
 	assert( Client != NULL );
 	assert( Req != NULL );
 
-#ifndef STRICT_RFC
 	/* Some IRC clients, for example BitchX, send the NICK and USER
 	 * commands in the wrong order ... */
-	if( Client_Type( Client ) == CLIENT_UNKNOWN
-	    || Client_Type( Client ) == CLIENT_GOTPASS
-	    || Client_Type( Client ) == CLIENT_GOTNICK
-	    || Client_Type( Client ) == CLIENT_GOTUSER
-	    || Client_Type( Client ) == CLIENT_USER
-	    || ( Client_Type( Client ) == CLIENT_SERVER && Req->argc == 1 ))
-#else
-	if( Client_Type( Client ) == CLIENT_UNKNOWN
-	    || Client_Type( Client ) == CLIENT_GOTPASS
-	    || Client_Type( Client ) == CLIENT_GOTNICK
-	    || Client_Type( Client ) == CLIENT_USER
-	    || ( Client_Type( Client ) == CLIENT_SERVER && Req->argc == 1 ))
+	if(Client_Type(Client) == CLIENT_UNKNOWN
+	    || Client_Type(Client) == CLIENT_GOTPASS
+	    || Client_Type(Client) == CLIENT_GOTNICK
+#ifndef STRICT_RFC
+	    || Client_Type(Client) == CLIENT_GOTUSER
 #endif
+	    || Client_Type(Client) == CLIENT_USER
+	    || Client_Type(Client) == CLIENT_SERVICE
+	    || (Client_Type(Client) == CLIENT_SERVER && Req->argc == 1))
 	{
 		/* User registration or change of nickname */
 
@@ -236,11 +261,11 @@ IRC_NICK( CLIENT *Client, REQUEST *Req )
 				return CONNECTED;
 		}
 
-		if(( Client_Type( target ) != CLIENT_USER )
-		   && ( Client_Type( target ) != CLIENT_SERVER ))
-		{
+		if (Client_Type(target) != CLIENT_USER &&
+		    Client_Type(target) != CLIENT_SERVICE &&
+		    Client_Type(target) != CLIENT_SERVER) {
 			/* New client */
-			Log( LOG_DEBUG, "Connection %d: got valid NICK command ...", 
+			LogDebug("Connection %d: got valid NICK command ...",
 			     Client_Conn( Client ));
 
 			/* Register new nickname of this client */
@@ -252,25 +277,22 @@ IRC_NICK( CLIENT *Client, REQUEST *Req )
 				return Hello_User( Client );
 			else
 				Client_SetType( Client, CLIENT_GOTNICK );
-		}
-		else
-		{
+		} else {
 			/* Nickname change */
 			if (Client_Conn(target) > NONE) {
 				/* Local client */
 				Log(LOG_INFO,
-				    "User \"%s\" changed nick (connection %d): \"%s\" -> \"%s\".",
-				    Client_Mask(target), Client_Conn(target),
-				    Client_ID(target), Req->argv[0]);
+				    "%s \"%s\" changed nick (connection %d): \"%s\" -> \"%s\".",
+				    Client_TypeText(target), Client_Mask(target),
+				    Client_Conn(target), Client_ID(target),
+				    Req->argv[0]);
 				Conn_UpdateIdle(Client_Conn(target));
-			}
-			else
-			{
+			} else {
 				/* Remote client */
-				Log( LOG_DEBUG,
-				     "User \"%s\" changed nick: \"%s\" -> \"%s\".",
-				     Client_Mask( target ), Client_ID( target ),
-				     Req->argv[0] );
+				LogDebug("%s \"%s\" changed nick: \"%s\" -> \"%s\".",
+					 Client_TypeText(target),
+					 Client_Mask(target), Client_ID(target),
+					 Req->argv[0]);
 			}
 
 			/* Inform all users and servers (which have to know)
@@ -294,28 +316,48 @@ IRC_NICK( CLIENT *Client, REQUEST *Req )
 		}
 
 		return CONNECTED;
-	}
-	else if( Client_Type( Client ) == CLIENT_SERVER )
-	{
-		/* Server introduces new client */
-
-		/* Falsche Anzahl Parameter? */
-		if( Req->argc != 7 ) return IRC_WriteStrClient( Client, ERR_NEEDMOREPARAMS_MSG, Client_ID( Client ), Req->command );
+	} else if(Client_Type(Client) == CLIENT_SERVER ||
+		  Client_Type(Client) == CLIENT_SERVICE) {
+		/* Server or service introduces new client */
+
+		/* Bad number of parameters? */
+		if (Req->argc != 2 && Req->argc != 7)
+			return IRC_WriteStrClient(Client, ERR_NEEDMOREPARAMS_MSG,
+						  Client_ID(Client), Req->command);
+
+		if (Req->argc >= 7) {
+			/* RFC 2813 compatible syntax */
+			nick = Req->argv[0];
+			hops = atoi(Req->argv[1]);
+			user = Req->argv[2];
+			hostname = Req->argv[3];
+			token = atoi(Req->argv[4]);
+			modes = Req->argv[5] + 1;
+			info = Req->argv[6];
+		} else {
+			/* RFC 1459 compatible syntax */
+			nick = Req->argv[0];
+			hops = 1;
+			user = Req->argv[0];
+			hostname = Client_ID(Client);
+			token = atoi(Req->argv[1]);
+			modes = "";
+			info = Req->argv[0];
+		}
 
-		/* Nick ueberpruefen */
-		c = Client_Search( Req->argv[0] );
-		if( c )
-		{
-			/* Der neue Nick ist auf diesem Server bereits registriert:
-			 * sowohl der neue, als auch der alte Client muessen nun
-			 * disconnectiert werden. */
+		c = Client_Search(nick);
+		if(c) {
+			/*
+			 * the new nick is already present on this server:
+			 * the new and the old one have to be disconnected now.
+			 */
 			Log( LOG_ERR, "Server %s introduces already registered nick \"%s\"!", Client_ID( Client ), Req->argv[0] );
 			Kill_Nick( Req->argv[0], "Nick collision" );
 			return CONNECTED;
 		}
 
-		/* Server, zu dem der Client connectiert ist, suchen */
-		intr_c = Client_GetFromToken( Client, atoi( Req->argv[4] ));
+		/* Find the Server this client is connected to */
+		intr_c = Client_GetFromToken(Client, token);
 		if( ! intr_c )
 		{
 			Log( LOG_ERR, "Server %s introduces nick \"%s\" on unknown server!?", Client_ID( Client ), Req->argv[0] );
@@ -323,24 +365,26 @@ IRC_NICK( CLIENT *Client, REQUEST *Req )
 			return CONNECTED;
 		}
 
-		/* Neue Client-Struktur anlegen */
-		c = Client_NewRemoteUser( intr_c, Req->argv[0], atoi( Req->argv[1] ), Req->argv[2], Req->argv[3], atoi( Req->argv[4] ), Req->argv[5] + 1, Req->argv[6], true);
+		c = Client_NewRemoteUser(intr_c, nick, hops, user, hostname,
+					 token, modes, info, true);
 		if( ! c )
 		{
-			/* Eine neue Client-Struktur konnte nicht angelegt werden.
-			 * Der Client muss disconnectiert werden, damit der Netz-
-			 * status konsistent bleibt. */
+			/* out of memory, need to disconnect client to keep network state consistent */
 			Log( LOG_ALERT, "Can't create client structure! (on connection %d)", Client_Conn( Client ));
 			Kill_Nick( Req->argv[0], "Server error" );
 			return CONNECTED;
 		}
 
-		modes = Client_Modes( c );
-		if( *modes ) Log( LOG_DEBUG, "User \"%s\" (+%s) registered (via %s, on %s, %d hop%s).", Client_Mask( c ), modes, Client_ID( Client ), Client_ID( intr_c ), Client_Hops( c ), Client_Hops( c ) > 1 ? "s": "" );
-		else Log( LOG_DEBUG, "User \"%s\" registered (via %s, on %s, %d hop%s).", Client_Mask( c ), Client_ID( Client ), Client_ID( intr_c ), Client_Hops( c ), Client_Hops( c ) > 1 ? "s": "" );
-
-		/* Andere Server, ausser dem Introducer, informieren */
-		IRC_WriteStrServersPrefix( Client, Client, "NICK %s %d %s %s %d %s :%s", Req->argv[0], atoi( Req->argv[1] ) + 1, Req->argv[2], Req->argv[3], Client_MyToken( intr_c ), Req->argv[5], Req->argv[6] );
+		/* RFC 2813: client is now fully registered, inform all the
+		 * other servers about the new user.
+		 * RFC 1459: announce the new client only after receiving the
+		 * USER command, first we need more information! */
+		if (Req->argc < 7) {
+			LogDebug("Client \"%s\" is being registered (RFC 1459) ...",
+				 Client_Mask(c));
+			Client_SetType(c, CLIENT_GOTNICK);
+		} else
+			Introduce_Client(Client, c, CLIENT_USER);
 
 		return CONNECTED;
 	}
@@ -348,63 +392,131 @@ IRC_NICK( CLIENT *Client, REQUEST *Req )
 } /* IRC_NICK */
 
 
+/**
+ * Handler for the IRC "USER" command.
+ *
+ * See RFC 2812, 3.1.3 "User message".
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
 GLOBAL bool
-IRC_USER( CLIENT *Client, REQUEST *Req )
+IRC_USER(CLIENT * Client, REQUEST * Req)
 {
+	CLIENT *c;
 #ifdef IDENTAUTH
 	char *ptr;
 #endif
 
-	assert( Client != NULL );
-	assert( Req != NULL );
+	assert(Client != NULL);
+	assert(Req != NULL);
 
+	if (Client_Type(Client) == CLIENT_GOTNICK ||
 #ifndef STRICT_RFC
-	if( Client_Type( Client ) == CLIENT_GOTNICK || Client_Type( Client ) == CLIENT_GOTPASS || Client_Type( Client ) == CLIENT_UNKNOWN )
-#else
-	if( Client_Type( Client ) == CLIENT_GOTNICK || Client_Type( Client ) == CLIENT_GOTPASS )
+	    Client_Type(Client) == CLIENT_UNKNOWN ||
 #endif
+	    Client_Type(Client) == CLIENT_GOTPASS)
 	{
-		/* Wrong number of parameters? */
-		if( Req->argc != 4 ) return IRC_WriteStrClient( Client, ERR_NEEDMOREPARAMS_MSG, Client_ID( Client ), Req->command );
+		/* New connection */
+		if (Req->argc != 4)
+			return IRC_WriteStrClient(Client,
+						  ERR_NEEDMOREPARAMS_MSG,
+						  Client_ID(Client),
+						  Req->command);
 
 		/* User name */
 #ifdef IDENTAUTH
-		ptr = Client_User( Client );
-		if( ! ptr || ! *ptr || *ptr == '~' ) Client_SetUser( Client, Req->argv[0], false );
+		ptr = Client_User(Client);
+		if (!ptr || !*ptr || *ptr == '~')
+			Client_SetUser(Client, Req->argv[0], false);
 #else
-		Client_SetUser( Client, Req->argv[0], false );
+		Client_SetUser(Client, Req->argv[0], false);
 #endif
+		Client_SetOrigUser(Client, Req->argv[0]);
 
-		/* "Real name" or user info text: Don't set it to the empty string, the original ircd
-		 * can't deal with such "real names" (e. g. "USER user * * :") ... */
-		if( *Req->argv[3] ) Client_SetInfo( Client, Req->argv[3] );
-		else Client_SetInfo( Client, "-" );
+		/* "Real name" or user info text: Don't set it to the empty
+		 * string, the original ircd can't deal with such "real names"
+		 * (e. g. "USER user * * :") ... */
+		if (*Req->argv[3])
+			Client_SetInfo(Client, Req->argv[3]);
+		else
+			Client_SetInfo(Client, "-");
 
-		Log( LOG_DEBUG, "Connection %d: got valid USER command ...", Client_Conn( Client ));
-		if( Client_Type( Client ) == CLIENT_GOTNICK ) return Hello_User( Client );
-		else Client_SetType( Client, CLIENT_GOTUSER );
+		LogDebug("Connection %d: got valid USER command ...",
+		    Client_Conn(Client));
+		if (Client_Type(Client) == CLIENT_GOTNICK)
+			return Hello_User(Client);
+		else
+			Client_SetType(Client, CLIENT_GOTUSER);
 		return CONNECTED;
+
+	} else if (Client_Type(Client) == CLIENT_SERVER ||
+		   Client_Type(Client) == CLIENT_SERVICE) {
+		/* Server/service updating an user */
+		if (Req->argc != 4)
+			return IRC_WriteStrClient(Client,
+						  ERR_NEEDMOREPARAMS_MSG,
+						  Client_ID(Client),
+						  Req->command);
+		c = Client_Search(Req->prefix);
+		if (!c)
+			return IRC_WriteStrClient(Client, ERR_NOSUCHNICK_MSG,
+						  Client_ID(Client),
+						  Req->prefix);
+
+		Client_SetUser(c, Req->argv[0], true);
+		Client_SetOrigUser(c, Req->argv[0]);
+		Client_SetHostname(c, Req->argv[1]);
+		Client_SetInfo(c, Req->argv[3]);
+
+		LogDebug("Connection %d: got valid USER command for \"%s\".",
+			 Client_Conn(Client), Client_Mask(c));
+
+		/* RFC 1459 style user registration?
+		 * Introduce client to network: */
+		if (Client_Type(c) == CLIENT_GOTNICK)
+			Introduce_Client(Client, c, CLIENT_USER);
+
+		return CONNECTED;
+	} else if (Client_Type(Client) == CLIENT_USER) {
+		/* Already registered connection */
+		return IRC_WriteStrClient(Client, ERR_ALREADYREGISTRED_MSG,
+					  Client_ID(Client));
+	} else {
+		/* Unexpected/invalid connection state? */
+		return IRC_WriteStrClient(Client, ERR_NOTREGISTERED_MSG,
+					  Client_ID(Client));
 	}
-	else if( Client_Type( Client ) == CLIENT_USER || Client_Type( Client ) == CLIENT_SERVER || Client_Type( Client ) == CLIENT_SERVICE )
-	{
-		return IRC_WriteStrClient( Client, ERR_ALREADYREGISTRED_MSG, Client_ID( Client ));
-	}
-	else return IRC_WriteStrClient( Client, ERR_NOTREGISTERED_MSG, Client_ID( Client ));
 } /* IRC_USER */
 
 
 /**
- * Service registration.
- * ngIRCd does not support services at the moment, so this function is a
- * dummy that returns ERR_ERRONEUSNICKNAME on each call.
+ * Handler for the IRC "SERVICE" command.
+ *
+ * This function implements IRC Services registration using the SERVICE command
+ * defined in RFC 2812 3.1.6 and RFC 2813 4.1.4.
+ *
+ * At the moment ngIRCd doesn't support directly linked services, so this
+ * function returns ERR_ERRONEUSNICKNAME when the SERVICE command has not been
+ * received from a peer server.
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED..
  */
 GLOBAL bool
 IRC_SERVICE(CLIENT *Client, REQUEST *Req)
 {
+	CLIENT *c, *intr_c;
+	char *nick, *user, *host, *info, *modes, *ptr;
+	int token, hops;
+
 	assert(Client != NULL);
 	assert(Req != NULL);
 
-	if (Client_Type(Client) != CLIENT_GOTPASS)
+	if (Client_Type(Client) != CLIENT_GOTPASS &&
+	    Client_Type(Client) != CLIENT_SERVER)
 		return IRC_WriteStrClient(Client, ERR_ALREADYREGISTRED_MSG,
 					  Client_ID(Client));
 
@@ -412,11 +524,118 @@ IRC_SERVICE(CLIENT *Client, REQUEST *Req)
 		return IRC_WriteStrClient(Client, ERR_NEEDMOREPARAMS_MSG,
 					  Client_ID(Client), Req->command);
 
-	return IRC_WriteStrClient(Client, ERR_ERRONEUSNICKNAME_MSG,
+	if (Client_Type(Client) != CLIENT_SERVER)
+		return IRC_WriteStrClient(Client, ERR_ERRONEUSNICKNAME_MSG,
 				  Client_ID(Client), Req->argv[0]);
+
+	/* Bad number of parameters? */
+	if (Req->argc != 6)
+		return IRC_WriteStrClient(Client, ERR_NEEDMOREPARAMS_MSG,
+					  Client_ID(Client), Req->command);
+
+	nick = Req->argv[0];
+	user = NULL; host = NULL;
+	token = atoi(Req->argv[1]);
+	hops = atoi(Req->argv[4]);
+	info = Req->argv[5];
+
+	/* Validate service name ("nick name") */
+	c = Client_Search(nick);
+	if(c) {
+		/* Nick name collission: disconnect (KILL) both clients! */
+		Log(LOG_ERR, "Server %s introduces already registered service \"%s\"!",
+		    Client_ID(Client), nick);
+		Kill_Nick(nick, "Nick collision");
+		return CONNECTED;
+	}
+
+	/* Get the server to which the service is connected */
+	intr_c = Client_GetFromToken(Client, token);
+	if (! intr_c) {
+		Log(LOG_ERR, "Server %s introduces service \"%s\" on unknown server!?",
+		    Client_ID(Client), nick);
+		Kill_Nick(nick, "Unknown server");
+		return CONNECTED;
+	}
+
+	/* Get user and host name */
+	ptr = strchr(nick, '@');
+	if (ptr) {
+		*ptr = '\0';
+		host = ++ptr;
+	}
+	if (!host)
+		host = Client_Hostname(intr_c);
+	ptr = strchr(nick, '!');
+	if (ptr) {
+		*ptr = '\0';
+		user = ++ptr;
+	}
+	if (!user)
+		user = nick;
+
+	/* According to RFC 2812/2813 parameter 4 <type> "is currently reserved
+	 * for future usage"; but we use it to transfer the modes and check
+	 * that the first character is a '+' sign and ignore it otherwise. */
+	modes = (Req->argv[3][0] == '+') ? ++Req->argv[3] : "";
+
+	c = Client_NewRemoteUser(intr_c, nick, hops, user, host,
+				 token, modes, info, true);
+	if (! c) {
+		/* Couldn't create client structure, so KILL the service to
+		 * keep network status consistent ... */
+		Log(LOG_ALERT, "Can't create client structure! (on connection %d)",
+		    Client_Conn(Client));
+		Kill_Nick(nick, "Server error");
+		return CONNECTED;
+	}
+
+	Introduce_Client(Client, c, CLIENT_SERVICE);
+	return CONNECTED;
 } /* IRC_SERVICE */
 
 
+/**
+ * Handler for the IRC "WEBIRC" command.
+ *
+ * See doc/Protocol.txt, section II.4:
+ * "Update webchat/proxy client information".
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
+GLOBAL bool
+IRC_WEBIRC(CLIENT *Client, REQUEST *Req)
+{
+	/* Exactly 4 parameters are requited */
+	if (Req->argc != 4)
+		return IRC_WriteStrClient(Client, ERR_NEEDMOREPARAMS_MSG,
+					  Client_ID(Client), Req->command);
+
+	if (!Conf_WebircPwd[0] || strcmp(Req->argv[0], Conf_WebircPwd) != 0)
+		return IRC_WriteStrClient(Client, ERR_PASSWDMISMATCH_MSG,
+					  Client_ID(Client));
+
+	LogDebug("Connection %d: got valid WEBIRC command: user=%s, host=%s, ip=%s",
+		 Client_Conn(Client), Req->argv[1], Req->argv[2], Req->argv[3]);
+
+	Client_SetUser(Client, Req->argv[1], true);
+	Client_SetOrigUser(Client, Req->argv[1]);
+	Client_SetHostname(Client, Req->argv[2]);
+	return CONNECTED;
+} /* IRC_WEBIRC */
+
+
+/**
+ * Handler for the IRC "QUIT" command.
+ *
+ * See RFC 2812, 3.1.7 "Quit", and RFC 2813, 4.1.5 "Quit".
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
 GLOBAL bool
 IRC_QUIT( CLIENT *Client, REQUEST *Req )
 {
@@ -439,7 +658,6 @@ IRC_QUIT( CLIENT *Client, REQUEST *Req )
 		target = Client_Search( Req->prefix );
 		if( ! target )
 		{
-			/* Den Client kennen wir nicht (mehr), also nichts zu tun. */
 			Log( LOG_WARNING, "Got QUIT from %s for unknown client!?", Client_ID( Client ));
 			return CONNECTED;
 		}
@@ -457,7 +675,7 @@ IRC_QUIT( CLIENT *Client, REQUEST *Req )
 			strlcat(quitmsg, "\"", sizeof quitmsg );
 		}
 
-		/* User, Service, oder noch nicht registriert */
+		/* User, Service, or not yet registered */
 		Conn_Close( Client_Conn( Client ), "Got QUIT command.", Req->argc == 1 ? quitmsg : NULL, true);
 
 		return DISCONNECTED;
@@ -465,6 +683,38 @@ IRC_QUIT( CLIENT *Client, REQUEST *Req )
 } /* IRC_QUIT */
 
 
+#ifndef STRICT_RFC
+
+/**
+ * Handler for HTTP command, e.g. GET and POST
+ *
+ * We handle these commands here to avoid the quite long timeout when
+ * some user tries to access this IRC daemon using an web browser ...
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
+GLOBAL bool
+IRC_QUIT_HTTP( CLIENT *Client, REQUEST *Req )
+{
+	Req->argc = 1;
+	Req->argv[0] = "Oops, HTTP request received? This is IRC!";
+	return IRC_QUIT(Client, Req);
+} /* IRC_QUIT_HTTP */
+
+#endif
+
+
+/**
+ * Handler for the IRC "PING" command.
+ *
+ * See RFC 2812, 3.7.2 "Ping message".
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
 GLOBAL bool
 IRC_PING(CLIENT *Client, REQUEST *Req)
 {
@@ -473,7 +723,6 @@ IRC_PING(CLIENT *Client, REQUEST *Req)
 	assert(Client != NULL);
 	assert(Req != NULL);
 
-	/* Wrong number of arguments? */
 	if (Req->argc < 1)
 		return IRC_WriteStrClient(Client, ERR_NOORIGIN_MSG,
 					  Client_ID(Client));
@@ -535,6 +784,15 @@ IRC_PING(CLIENT *Client, REQUEST *Req)
 } /* IRC_PING */
 
 
+/**
+ * Handler for the IRC "PONG" command.
+ *
+ * See RFC 2812, 3.7.3 "Pong message".
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
 GLOBAL bool
 IRC_PONG(CLIENT *Client, REQUEST *Req)
 {
@@ -579,7 +837,7 @@ IRC_PONG(CLIENT *Client, REQUEST *Req)
 
 	/* The connection timestamp has already been updated when the data has
 	 * been read from so socket, so we don't need to update it here. */
-
+#ifdef DEBUG
 	if (Client_Conn(Client) > NONE)
 		Log(LOG_DEBUG,
 			"Connection %d: received PONG. Lag: %ld seconds.",
@@ -588,34 +846,158 @@ IRC_PONG(CLIENT *Client, REQUEST *Req)
 	else
 		 Log(LOG_DEBUG,
 			"Connection %d: received PONG.", Client_Conn(Client));
-
+#endif
 	return CONNECTED;
 } /* IRC_PONG */
 
 
+/**
+ * Initiate client registration.
+ *
+ * This function is called after the daemon received the required NICK and
+ * USER commands of a new client. If the daemon is compiled with support for
+ * PAM, the authentication sub-processs is forked; otherwise the global server
+ * password is checked.
+ *
+ * @param Client	The client logging in.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
 static bool
 Hello_User(CLIENT * Client)
 {
+#ifdef PAM
+	int pipefd[2], result;
+	CONN_ID conn;
+	pid_t pid;
+
 	assert(Client != NULL);
+	conn = Client_Conn(Client);
+
+	if (!Conf_PAM) {
+		/* Don't do any PAM authentication at all, instead emulate
+		 * the beahiour of the daemon compiled without PAM support:
+		 * because there can't be any "server password", all
+		 * passwords supplied are classified as "wrong". */
+		if(Client_Password(Client)[0] == '\0')
+			return Hello_User_PostAuth(Client);
+		Reject_Client(Client);
+		return DISCONNECTED;
+	}
 
-	/* Check password ... */
+	/* Fork child process for PAM authentication; and make sure that the
+	 * process timeout is set higher than the login timeout! */
+	pid = Proc_Fork(Conn_GetProcStat(conn), pipefd,
+			cb_Read_Auth_Result, Conf_PongTimeout + 1);
+	if (pid > 0) {
+		LogDebug("Authenticator for connection %d created (PID %d).",
+			 conn, pid);
+		return CONNECTED;
+	} else {
+		/* Sub process */
+		Log_Init_Subprocess("Auth");
+		result = PAM_Authenticate(Client);
+		if (write(pipefd[1], &result, sizeof(result)) != sizeof(result))
+			Log_Subprocess(LOG_ERR,
+				       "Failed to pipe result to parent!");
+		Log_Exit_Subprocess("Auth");
+		exit(0);
+	}
+#else
+	assert(Client != NULL);
+
+	/* Check global server password ... */
 	if (strcmp(Client_Password(Client), Conf_ServerPwd) != 0) {
 		/* Bad password! */
-		Log(LOG_ERR,
-		    "User \"%s\" rejected (connection %d): Bad password!",
-		    Client_Mask(Client), Client_Conn(Client));
-		Conn_Close(Client_Conn(Client), NULL, "Bad password", true);
+		Reject_Client(Client);
 		return DISCONNECTED;
 	}
+	return Hello_User_PostAuth(Client);
+#endif
+}
+
+
+#ifdef PAM
+
+/**
+ * Read result of the authenticatior sub-process from pipe
+ *
+ * @param r_fd		File descriptor of the pipe.
+ * @param events	(ignored IO specification)
+ */
+static void
+cb_Read_Auth_Result(int r_fd, UNUSED short events)
+{
+	CONN_ID conn;
+	CLIENT *client;
+	int result;
+	size_t len;
+	PROC_STAT *proc;
+
+	LogDebug("Auth: Got callback on fd %d, events %d", r_fd, events);
+	conn = Conn_GetFromProc(r_fd);
+	if (conn == NONE) {
+		/* Ops, none found? Probably the connection has already
+		 * been closed!? We'll ignore that ... */
+		io_close(r_fd);
+		LogDebug("Auth: Got callback for unknown connection!?");
+		return;
+	}
+	proc = Conn_GetProcStat(conn);
+	client = Conn_GetClient(conn);
+
+	/* Read result from pipe */
+	len = Proc_Read(proc, &result, sizeof(result));
+	if (len == 0)
+		return;
+
+	if (len != sizeof(result)) {
+		Log(LOG_CRIT, "Auth: Got malformed result!");
+		Reject_Client(client);
+		return;
+	}
+
+	if (result == true) {
+		Client_SetUser(client, Client_OrigUser(client), true);
+		(void)Hello_User_PostAuth(client);
+	} else
+		Reject_Client(client);
+}
+
+#endif
 
-	Log(LOG_NOTICE, "User \"%s\" registered (connection %d).",
+
+/**
+ * Reject a client because of wrong password.
+ *
+ * This function is called either when the global server password or a password
+ * checked using PAM has been wrong.
+ *
+ * @param Client	The client to reject.
+ */
+static void
+Reject_Client(CLIENT *Client)
+{
+	Log(LOG_ERR,
+	    "User \"%s\" rejected (connection %d): Access denied!",
 	    Client_Mask(Client), Client_Conn(Client));
+	Conn_Close(Client_Conn(Client), NULL,
+		   "Access denied! Bad password?", true);
+}
 
-	/* Inform other servers */
-	IRC_WriteStrServers(NULL, "NICK %s 1 %s %s 1 +%s :%s",
-			    Client_ID(Client), Client_User(Client),
-			    Client_Hostname(Client), Client_Modes(Client),
-			    Client_Info(Client));
+
+/**
+ * Finish client registration.
+ *
+ * Introduce the new client to the network and send all "hello messages"
+ * to it after authentication has been succeeded.
+ *
+ * @param Client	The client logging in.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
+static bool
+Hello_User_PostAuth(CLIENT *Client)
+{
+	Introduce_Client(NULL, Client, CLIENT_USER);
 
 	if (!IRC_WriteStrClient
 	    (Client, RPL_WELCOME_MSG, Client_ID(Client), Client_Mask(Client)))
@@ -639,8 +1021,6 @@ Hello_User(CLIENT * Client)
 	if (!IRC_Send_ISUPPORT(Client))
 		return DISCONNECTED;
 
-	Client_SetType(Client, CLIENT_USER);
-
 	if (!IRC_Send_LUSERS(Client))
 		return DISCONNECTED;
 	if (!IRC_Show_MOTD(Client))
@@ -650,9 +1030,15 @@ Hello_User(CLIENT * Client)
 	IRC_SetPenalty(Client, 1);
 
 	return CONNECTED;
-} /* Hello_User */
+}
 
 
+/**
+ * Kill all users with a specific nick name in the network.
+ *
+ * @param Nick		Nick name.
+ * @param Reason	Reason for the KILL.
+ */
 static void
 Kill_Nick( char *Nick, char *Reason )
 {
@@ -671,4 +1057,97 @@ Kill_Nick( char *Nick, char *Reason )
 } /* Kill_Nick */
 
 
+/**
+ * Introduce a new user or service client in the network.
+ *
+ * @param From		Remote server introducing the client or NULL (local).
+ * @param Client	New client.
+ * @param Type		Type of the client (CLIENT_USER or CLIENT_SERVICE).
+ */
+static void
+Introduce_Client(CLIENT *From, CLIENT *Client, int Type)
+{
+	/* Set client type (user or service) */
+	Client_SetType(Client, Type);
+
+	if (From) {
+		if (Conf_IsService(Conf_GetServer(Client_Conn(From)),
+				   Client_ID(Client)))
+			Client_SetType(Client, CLIENT_SERVICE);
+		LogDebug("%s \"%s\" (+%s) registered (via %s, on %s, %d hop%s).",
+			 Client_TypeText(Client), Client_Mask(Client),
+			 Client_Modes(Client), Client_ID(From),
+			 Client_ID(Client_Introducer(Client)),
+			 Client_Hops(Client), Client_Hops(Client) > 1 ? "s": "");
+	} else {
+		Log(LOG_NOTICE, "%s \"%s\" registered (connection %d).",
+		    Client_TypeText(Client), Client_Mask(Client),
+		    Client_Conn(Client));
+		Log_ServerNotice('c', "Client connecting: %s (%s@%s) [%s] - %s",
+			         Client_ID(Client), Client_User(Client),
+				 Client_Hostname(Client),
+				 Conn_IPA(Client_Conn(Client)),
+				 Client_TypeText(Client));
+	}
+
+	/* Inform other servers */
+	IRC_WriteStrServersPrefixFlag_CB(From,
+				From != NULL ? From : Client_ThisServer(),
+				'\0', cb_introduceClient, (void *)Client);
+} /* Introduce_Client */
+
+
+/**
+ * Introduce a new user or service client to a remote server.
+ *
+ * This function differentiates between RFC1459 and RFC2813 server links and
+ * generates the appropriate commands to register the new user or service.
+ *
+ * @param To		The remote server to inform.
+ * @param Prefix	Prefix for the generated commands.
+ * @param data		CLIENT structure of the new client.
+ */
+static void
+cb_introduceClient(CLIENT *To, CLIENT *Prefix, void *data)
+{
+	CLIENT *c = (CLIENT *)data;
+	CONN_ID conn;
+	char *modes, *user, *host;
+
+	modes = Client_Modes(c);
+	user = Client_User(c) ? Client_User(c) : "-";
+	host = Client_Hostname(c) ? Client_Hostname(c) : "-";
+
+	conn = Client_Conn(To);
+	if (Conn_Options(conn) & CONN_RFC1459) {
+		/* RFC 1459 mode: separate NICK and USER commands */
+		Conn_WriteStr(conn, "NICK %s :%d", Client_ID(c),
+			      Client_Hops(c) + 1);
+		Conn_WriteStr(conn, ":%s USER %s %s %s :%s",
+			      Client_ID(c), user, host,
+			      Client_ID(Client_Introducer(c)), Client_Info(c));
+		if (modes[0])
+			Conn_WriteStr(conn, ":%s MODE %s +%s",
+				      Client_ID(c), Client_ID(c), modes);
+	} else {
+		/* RFC 2813 mode: one combined NICK or SERVICE command */
+		if (Client_Type(c) == CLIENT_SERVICE
+		    && strchr(Client_Flags(To), 'S'))
+			IRC_WriteStrClientPrefix(To, Prefix,
+					 "SERVICE %s %d * +%s %d :%s",
+					 Client_Mask(c),
+					 Client_MyToken(Client_Introducer(c)),
+					 Client_Modes(c), Client_Hops(c) + 1,
+					 Client_Info(c));
+		else
+			IRC_WriteStrClientPrefix(To, Prefix,
+					 "NICK %s %d %s %s %d +%s :%s",
+					 Client_ID(c), Client_Hops(c) + 1,
+					 user, host,
+					 Client_MyToken(Client_Introducer(c)),
+					 modes, Client_Info(c));
+	}
+} /* cb_introduceClient */
+
+
 /* -eof- */