X-Git-Url: https://arthur.barton.de/cgi-bin/gitweb.cgi?p=ngircd-alex.git;a=blobdiff_plain;f=src%2Fngircd%2Fresolve.c;h=dbf28736ab8c2329705be524c5d893be5266e230;hp=955ef4d9536f38903e83c04cac6ef1863f700f79;hb=20ce56cc5bdbee652f73499e3b03714ecbb45085;hpb=63c36773e4240e3d1b768d6a117e5178dbffc7df

diff --git a/src/ngircd/resolve.c b/src/ngircd/resolve.c
index 955ef4d9..dbf28736 100644
--- a/src/ngircd/resolve.c
+++ b/src/ngircd/resolve.c
@@ -1,22 +1,21 @@
 /*
  * ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001,2002 by Alexander Barton (alex@barton.de)
+ * Copyright (c)2001-2003 by Alexander Barton (alex@barton.de)
  *
- * Dieses Programm ist freie Software. Sie koennen es unter den Bedingungen
- * der GNU General Public License (GPL), wie von der Free Software Foundation
- * herausgegeben, weitergeben und/oder modifizieren, entweder unter Version 2
- * der Lizenz oder (wenn Sie es wuenschen) jeder spaeteren Version.
- * Naehere Informationen entnehmen Sie bitter der Datei COPYING. Eine Liste
- * der an ngIRCd beteiligten Autoren finden Sie in der Datei AUTHORS.
+ * 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.
  *
- * $Id: resolve.c,v 1.3 2002/06/09 13:19:08 alex Exp $
- *
- * resolve.c: asyncroner Resolver
+ * Asynchronous resolver
  */
 
 
 #include "portab.h"
 
+static char UNUSED id[] = "$Id: resolve.c,v 1.27 2007/11/25 18:42:37 fw Exp $";
+
 #include "imp.h"
 #include <assert.h>
 #include <errno.h>
@@ -25,225 +24,264 @@
 #include <unistd.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
-#include <arpa/inet.h>
 #include <netdb.h>
 
+#ifdef IDENTAUTH
+#ifdef HAVE_IDENT_H
+#include <ident.h>
+#endif
+#endif
+
 #include "conn.h"
 #include "defines.h"
 #include "log.h"
+#include "tool.h"
 
 #include "exp.h"
 #include "resolve.h"
+#include "io.h"
 
 
-LOCAL VOID Do_ResolveAddr PARAMS(( struct sockaddr_in *Addr, INT w_fd ));
-LOCAL VOID Do_ResolveName PARAMS(( CHAR *Host, INT w_fd ));
+static void Do_ResolveAddr PARAMS(( struct sockaddr_in *Addr, int Sock, int w_fd ));
+static void Do_ResolveName PARAMS(( const char *Host, int w_fd ));
+static bool register_callback PARAMS((RES_STAT *s, void (*cbfunc)(int, short)));
 
 #ifdef h_errno
-LOCAL CHAR *Get_Error PARAMS(( INT H_Error ));
+static char *Get_Error PARAMS(( int H_Error ));
 #endif
 
-
-GLOBAL VOID
-Resolve_Init( VOID )
+static pid_t
+Resolver_fork(int *pipefds)
 {
-	/* Modul initialisieren */
-
-	FD_ZERO( &Resolver_FDs );
-} /* Resolve_Init */
+	pid_t pid;
 
+	if (pipe(pipefds) != 0) {
+                Log( LOG_ALERT, "Resolver: Can't create output pipe: %s!", strerror( errno ));
+                return -1;
+	}
 
-GLOBAL RES_STAT *
-Resolve_Addr( struct sockaddr_in *Addr )
-{
-	/* IP (asyncron!) aufloesen. Bei Fehler, z.B. wenn der
-	 * Child-Prozess nicht erzeugt werden kann, wird NULL geliefert.
-	 * Der Host kann dann nicht aufgeloest werden. */
+	pid = fork();
+	switch(pid) {
+		case -1:
+			Log( LOG_CRIT, "Resolver: Can't fork: %s!", strerror( errno ));
+			close(pipefds[0]);
+			close(pipefds[1]);
+			return -1;
+		case 0: /* child */
+			close(pipefds[0]);
+			Log_Init_Resolver( );
+			return 0;
+	}
+	/* parent */
+	close(pipefds[1]);
+	return pid; 
+}
 
-	RES_STAT *s;
-	INT pid;
 
-	/* Speicher anfordern */
-	s = malloc( sizeof( RES_STAT ));
-	if( ! s )
-	{
-		Log( LOG_EMERG, "Resolver: Can't allocate memory! [Resolve_Addr]" );
-		return NULL;
-	}
+/**
+ * Resolve IP (asynchronous!).
+ */
+GLOBAL bool
+Resolve_Addr(RES_STAT * s, struct sockaddr_in *Addr, int identsock,
+	     void (*cbfunc) (int, short))
+{
+	int pipefd[2];
+	pid_t pid;
 
-	/* Pipe fuer Antwort initialisieren */
-	if( pipe( s->pipe ) != 0 )
-	{
-		free( s );
-		Log( LOG_ALERT, "Resolver: Can't create output pipe: %s!", strerror( errno ));
-		return NULL;
-	}
+	assert(s != NULL);
 
-	/* Sub-Prozess erzeugen */
-	pid = fork( );
-	if( pid > 0 )
-	{
-		/* Haupt-Prozess */
+	pid = Resolver_fork(pipefd);
+	if (pid > 0) {
+#ifdef DEBUG
 		Log( LOG_DEBUG, "Resolver for %s created (PID %d).", inet_ntoa( Addr->sin_addr ), pid );
-		FD_SET( s->pipe[0], &Resolver_FDs );
-		if( s->pipe[0] > Conn_MaxFD ) Conn_MaxFD = s->pipe[0];
+#endif
 		s->pid = pid;
-		return s;
-	}
-	else if( pid == 0 )
-	{
-		/* Sub-Prozess */
-		Log_Init_Resolver( );
-		Do_ResolveAddr( Addr, s->pipe[1] );
+		s->resolver_fd = pipefd[0];
+		return register_callback(s, cbfunc);
+	} else if( pid == 0 ) {
+		/* Sub process */
+		Do_ResolveAddr( Addr, identsock, pipefd[1]);
 		Log_Exit_Resolver( );
-		exit( 0 );
-	}
-	else
-	{
-		/* Fehler */
-		free( s );
-		Log( LOG_CRIT, "Resolver: Can't fork: %s!", strerror( errno ));
-		return NULL;
+		exit(0);
 	}
+	return false;
 } /* Resolve_Addr */
 
 
-GLOBAL RES_STAT *
-Resolve_Name( CHAR *Host )
+/**
+ * Resolve hostname (asynchronous!).
+ */
+GLOBAL bool
+Resolve_Name( RES_STAT *s, const char *Host, void (*cbfunc)(int, short))
 {
-	/* Hostnamen (asyncron!) aufloesen. Bei Fehler, z.B. wenn der
-	 * Child-Prozess nicht erzeugt werden kann, wird NULL geliefert.
-	 * Der Host kann dann nicht aufgeloest werden. */
-
-	RES_STAT *s;
-	INT pid;
+	int pipefd[2];
+	pid_t pid;
 
-	/* Speicher anfordern */
-	s = malloc( sizeof( RES_STAT ));
-	if( ! s )
-	{
-		Log( LOG_EMERG, "Resolver: Can't allocate memory! [Resolve_Name]" );
-		return NULL;
-	}
+	assert(s != NULL);
 
-	/* Pipe fuer Antwort initialisieren */
-	if( pipe( s->pipe ) != 0 )
-	{
-		free( s );
-		Log( LOG_ALERT, "Resolver: Can't create output pipe: %s!", strerror( errno ));
-		return NULL;
-	}
-
-	/* Sub-Prozess erzeugen */
-	pid = fork( );
-	if( pid > 0 )
-	{
-		/* Haupt-Prozess */
+	pid = Resolver_fork(pipefd);
+	if (pid > 0) {
+		/* Main process */
+#ifdef DEBUG
 		Log( LOG_DEBUG, "Resolver for \"%s\" created (PID %d).", Host, pid );
-		FD_SET( s->pipe[0], &Resolver_FDs );
-		if( s->pipe[0] > Conn_MaxFD ) Conn_MaxFD = s->pipe[0];
+#endif
 		s->pid = pid;
-		return s;
-	}
-	else if( pid == 0 )
-	{
-		/* Sub-Prozess */
-		Log_Init_Resolver( );
-		Do_ResolveName( Host, s->pipe[1] );
+		s->resolver_fd = pipefd[0];
+		return register_callback(s, cbfunc);
+	} else if( pid == 0 ) {
+		/* Sub process */
+		Do_ResolveName(Host, pipefd[1]);
 		Log_Exit_Resolver( );
-		exit( 0 );
-	}
-	else
-	{
-		/* Fehler */
-		free( s );
-		Log( LOG_CRIT, "Resolver: Can't fork: %s!", strerror( errno ));
-		return NULL;
+		exit(0);
 	}
+	return false;
 } /* Resolve_Name */
 
 
-LOCAL VOID
-Do_ResolveAddr( struct sockaddr_in *Addr, INT w_fd )
+GLOBAL void
+Resolve_Init(RES_STAT *s)
 {
-	/* Resolver Sub-Prozess: IP aufloesen und Ergebnis in Pipe schreiben. */
+	assert(s != NULL);
+	s->resolver_fd = -1;
+	s->pid = 0;
+}
 
-	CHAR hostname[HOST_LEN];
-	struct hostent *h;
 
-	Log_Resolver( LOG_DEBUG, "Now resolving %s ...", inet_ntoa( Addr->sin_addr ));
+static void
+Do_ResolveAddr( struct sockaddr_in *Addr, int identsock, int w_fd )
+{
+	/* Resolver sub-process: resolve IP address and write result into
+	 * pipe to parent. */
 
-	/* Namen aufloesen */
-	h = gethostbyaddr( (CHAR *)&Addr->sin_addr, sizeof( Addr->sin_addr ), AF_INET );
-	if( h ) strcpy( hostname, h->h_name );
-	else
-	{
+	char hostname[HOST_LEN];
+	char ipstr[HOST_LEN];
+	struct hostent *h;
+	size_t len;
+	struct in_addr *addr;
+	char *ntoaptr;
+	array resolved_addr;
+#ifdef IDENTAUTH
+	char *res;
+#endif
+	array_init(&resolved_addr);
+	/* Resolve IP address */
+#ifdef DEBUG
+	Log_Resolver( LOG_DEBUG, "Now resolving %s ...", inet_ntoa( Addr->sin_addr ));
+#endif
+	h = gethostbyaddr( (char *)&Addr->sin_addr, sizeof( Addr->sin_addr ), AF_INET );
+	if (!h) {
 #ifdef h_errno
 		Log_Resolver( LOG_WARNING, "Can't resolve address \"%s\": %s!", inet_ntoa( Addr->sin_addr ), Get_Error( h_errno ));
 #else
 		Log_Resolver( LOG_WARNING, "Can't resolve address \"%s\"!", inet_ntoa( Addr->sin_addr ));
 #endif	
-		strcpy( hostname, inet_ntoa( Addr->sin_addr ));
+		strlcpy( hostname, inet_ntoa( Addr->sin_addr ), sizeof( hostname ));
+	} else {
+ 		strlcpy( hostname, h->h_name, sizeof( hostname ));
+
+		h = gethostbyname( hostname );
+		if ( h ) {
+			if (memcmp(h->h_addr, &Addr->sin_addr, sizeof (struct in_addr))) {
+				addr = (struct in_addr*) h->h_addr;
+				strlcpy(ipstr, inet_ntoa(*addr), sizeof ipstr); 
+				ntoaptr = inet_ntoa( Addr->sin_addr );
+				Log(LOG_WARNING,"Possible forgery: %s resolved to %s (which is at ip %s!)",
+										ntoaptr, hostname, ipstr);
+				strlcpy( hostname, ntoaptr, sizeof hostname);
+			}
+		} else {
+			ntoaptr = inet_ntoa( Addr->sin_addr );
+			Log(LOG_WARNING, "Possible forgery: %s resolved to %s (which has no ip address)",
+											ntoaptr, hostname);
+			strlcpy( hostname, ntoaptr, sizeof hostname);
+		}
 	}
+	Log_Resolver( LOG_DEBUG, "Ok, translated %s to \"%s\".", inet_ntoa( Addr->sin_addr ), hostname );
 
-	/* Antwort an Parent schreiben */
-	if( write( w_fd, hostname, strlen( hostname ) + 1 ) != ( strlen( hostname ) + 1 ))
-	{
-		Log_Resolver( LOG_CRIT, "Resolver: Can't write to parent: %s!", strerror( errno ));
+	len = strlen( hostname ); 
+	hostname[len] = '\n'; len++;
+	if (!array_copyb(&resolved_addr, hostname, len )) {
+		Log_Resolver( LOG_CRIT, "Resolver: Can't copy resolved name: %s!", strerror( errno ));
 		close( w_fd );
 		return;
 	}
 
-	Log_Resolver( LOG_DEBUG, "Ok, translated %s to \"%s\".", inet_ntoa( Addr->sin_addr ), hostname );
+#ifdef IDENTAUTH
+	assert(identsock >= 0);
+	if (identsock >= 0) {
+		/* Do "IDENT" (aka "AUTH") lookup and append result to resolved_addr array */
+#ifdef DEBUG
+		Log_Resolver( LOG_DEBUG, "Doing IDENT lookup on socket %d ...", identsock );
+#endif
+		res = ident_id( identsock, 10 );
+#ifdef DEBUG
+		Log_Resolver(LOG_DEBUG, "Ok, IDENT lookup on socket %d done: \"%s\"",
+							identsock, res ? res : "(NULL)" );
+#endif
+		if (res && !array_cats(&resolved_addr, res)) {
+			Log_Resolver(LOG_WARNING, "Resolver: Cannot copy IDENT result: %s!", strerror(errno));
+			/* omit ident and return hostname only */ 
+		}
+
+		if (res) free(res);
+	}
+#else
+	(void)identsock;
+#endif
+	len = array_bytes(&resolved_addr);
+	if( (size_t)write( w_fd, array_start(&resolved_addr), len) != len )
+		Log_Resolver( LOG_CRIT, "Resolver: Can't write result to parent: %s!", strerror( errno ));
+
+	close(w_fd);
+	array_free(&resolved_addr);
 } /* Do_ResolveAddr */
 
 
-LOCAL VOID
-Do_ResolveName( CHAR *Host, INT w_fd )
+static void
+Do_ResolveName( const char *Host, int w_fd )
 {
-	/* Resolver Sub-Prozess: Name aufloesen und Ergebnis in Pipe schreiben. */
+	/* Resolver sub-process: resolve name and write result into pipe
+	 * to parent. */
 
-	CHAR ip[16];
+	char ip[16];
 	struct hostent *h;
 	struct in_addr *addr;
+	size_t len;
 
 	Log_Resolver( LOG_DEBUG, "Now resolving \"%s\" ...", Host );
 
-	/* Namen aufloesen */
+	/* Resolve hostname */
 	h = gethostbyname( Host );
-	if( h )
-	{
+	if( h ) {
 		addr = (struct in_addr *)h->h_addr;
-		strcpy( ip, inet_ntoa( *addr ));
-	}
-	else
-	{
+		strlcpy( ip, inet_ntoa( *addr ), sizeof( ip ));
+	} else {
 #ifdef h_errno
 		Log_Resolver( LOG_WARNING, "Can't resolve \"%s\": %s!", Host, Get_Error( h_errno ));
 #else
 		Log_Resolver( LOG_WARNING, "Can't resolve \"%s\"!", Host );
 #endif
-		strcpy( ip, "" );
+		close(w_fd);
+		return;
 	}
-
-	/* Antwort an Parent schreiben */
-	if( write( w_fd, ip, strlen( ip ) + 1 ) != ( strlen( ip ) + 1 ))
-	{
+#ifdef DEBUG
+	Log_Resolver( LOG_DEBUG, "Ok, translated \"%s\" to %s.", Host, ip );
+#endif
+	/* Write result into pipe to parent */
+	len = strlen( ip );
+	if ((size_t)write( w_fd, ip, len ) != len) {
 		Log_Resolver( LOG_CRIT, "Resolver: Can't write to parent: %s!", strerror( errno ));
 		close( w_fd );
-		return;
 	}
-
-	if( ip[0] ) Log_Resolver( LOG_DEBUG, "Ok, translated \"%s\" to %s.", Host, ip );
 } /* Do_ResolveName */
 
 
 #ifdef h_errno
 
-LOCAL CHAR *
-Get_Error( INT H_Error )
+static char *
+Get_Error( int H_Error )
 {
-	/* Fehlerbeschreibung fuer H_Error liefern */
+	/* Get error message for H_Error */
 
 	switch( H_Error )
 	{
@@ -263,4 +301,65 @@ Get_Error( INT H_Error )
 #endif
 
 
+static bool
+register_callback( RES_STAT *s, void (*cbfunc)(int, short))
+{
+	assert(cbfunc != NULL);
+	assert(s != NULL);
+	assert(s->resolver_fd >= 0);
+
+	if (io_setnonblock(s->resolver_fd) &&
+		io_event_create(s->resolver_fd, IO_WANTREAD, cbfunc))
+			return true;
+
+	Log( LOG_CRIT, "Resolver: Could not register callback function: %s!", strerror(errno));
+	close(s->resolver_fd);
+	Resolve_Init(s);
+	return false;
+}
+
+
+GLOBAL bool
+Resolve_Shutdown( RES_STAT *s)
+{
+	bool ret = false;
+
+	assert(s != NULL);
+	assert(s->resolver_fd >= 0);
+
+	if (s->resolver_fd >= 0)
+		ret = io_close(s->resolver_fd);
+
+	Resolve_Init(s);
+	return ret;
+}
+
+
+/**
+ * Read result of resolver sub-process from pipe
+ */
+GLOBAL size_t
+Resolve_Read( RES_STAT *s, void* readbuf, size_t buflen)
+{
+	ssize_t bytes_read;
+
+	assert(buflen > 0);
+
+	/* Read result from pipe */
+	bytes_read = read(s->resolver_fd, readbuf, buflen);
+	if (bytes_read < 0) {
+		if (errno == EAGAIN)
+			return 0;
+
+		Log( LOG_CRIT, "Resolver: Can't read result: %s!", strerror(errno));
+		bytes_read = 0;
+	}
+#ifdef DEBUG
+	else if (bytes_read == 0)
+		Log( LOG_DEBUG, "Resolver: Can't read result: EOF");
+#endif
+	Resolve_Shutdown(s);
+	return (size_t)bytes_read;
+}
 /* -eof- */
+