X-Git-Url: https://arthur.barton.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fngircd%2Fresolve.c;h=d2c01775dfa4aa280d81edc9e10c89c2cee795fa;hb=47ca178a219d682c589b27e64ee1a4e936cc7bdc;hp=d261fd0a5873c2c7242b01d190d6bddc7dde7428;hpb=afef7dee82264a5c0981ac66584c8888a1329827;p=ngircd-alex.git

diff --git a/src/ngircd/resolve.c b/src/ngircd/resolve.c
index d261fd0a..d2c01775 100644
--- a/src/ngircd/resolve.c
+++ b/src/ngircd/resolve.c
@@ -14,7 +14,7 @@
 
 #include "portab.h"
 
-static char UNUSED id[] = "$Id: resolve.c,v 1.13 2005/07/07 18:39:08 fw Exp $";
+static char UNUSED id[] = "$Id: resolve.c,v 1.26 2006/12/17 22:50:51 fw Exp $";
 
 #include "imp.h"
 #include <assert.h>
@@ -42,205 +42,203 @@ static char UNUSED id[] = "$Id: resolve.c,v 1.13 2005/07/07 18:39:08 fw Exp $";
 #include "io.h"
 
 
-#ifdef IDENTAUTH
-LOCAL void Do_ResolveAddr PARAMS(( struct sockaddr_in *Addr, int Sock, int w_fd ));
-#else
-LOCAL void Do_ResolveAddr PARAMS(( struct sockaddr_in *Addr, int w_fd ));
-#endif
-
-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
 
-LOCAL RES_STAT *New_Res_Stat PARAMS(( void ));
+static pid_t
+Resolver_fork(int *pipefds)
+{
+	pid_t pid;
 
+	if (pipe(pipefds) != 0) {
+                Log( LOG_ALERT, "Resolver: Can't create output pipe: %s!", strerror( errno ));
+                return -1;
+	}
 
-static void
-cb_resolver(int fd, short unused) {
-	(void) unused;	/* shut up compiler warning */
-	Read_Resolver_Result(fd);
+	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; 
 }
 
 
-#ifdef IDENTAUTH
-GLOBAL RES_STAT *
-Resolve_Addr( struct sockaddr_in *Addr, int Sock )
-#else
-GLOBAL RES_STAT *
-Resolve_Addr( struct sockaddr_in *Addr )
-#endif
+/**
+ * Resolve IP (asynchronous!).
+ */
+GLOBAL bool
+Resolve_Addr(RES_STAT * s, struct sockaddr_in *Addr, int identsock,
+	     void (*cbfunc) (int, short))
 {
-	/* Resolve IP (asynchronous!). On errors, e.g. if the child process
-	 * can't be forked, this functions returns NULL. */
-
-	RES_STAT *s;
-	int pid;
+	int pipefd[2];
+	pid_t pid;
 
-	s = New_Res_Stat( );
-	if( ! s ) return NULL;
+	assert(s != NULL);
 
-	/* For sub-process */
-	pid = fork( );
-	if( pid > 0 )
-	{
-		close( s->pipe[1] );
-		/* Main process */
+	pid = Resolver_fork(pipefd);
+	if (pid > 0) {
+#ifdef DEBUG
 		Log( LOG_DEBUG, "Resolver for %s created (PID %d).", inet_ntoa( Addr->sin_addr ), pid );
-		if (!io_setnonblock( s->pipe[0] )) {
-			Log( LOG_DEBUG, "Could not set Non-Blocking mode for pipefd %d", s->pipe[0] );
-			goto out;
-		}
-		if (!io_event_create( s->pipe[0], IO_WANTREAD, cb_resolver )) {
-			Log( LOG_DEBUG, "Could not add pipefd %dto event watchlist: %s",
-								s->pipe[0], strerror(errno) );
-			goto out;
-		}
+#endif
 		s->pid = pid;
-		return s;
-	}
-	else if( pid == 0 )
-	{
-		close( s->pipe[0] );
+		s->resolver_fd = pipefd[0];
+		return register_callback(s, cbfunc);
+	} else if( pid == 0 ) {
 		/* Sub process */
-		Log_Init_Resolver( );
-#ifdef IDENTAUTH
-		Do_ResolveAddr( Addr, Sock, s->pipe[1] );
-#else
-		Do_ResolveAddr( Addr, s->pipe[1] );
-#endif
+		Do_ResolveAddr( Addr, identsock, pipefd[1]);
 		Log_Exit_Resolver( );
-		exit( 0 );
+		exit(0);
 	}
-	
-	Log( LOG_CRIT, "Resolver: Can't fork: %s!", strerror( errno ));
-
-out: /* Error! */
-	close( s->pipe[0] );
-	free( s );
-return NULL;
+	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))
 {
-	/* Resolve hostname (asynchronous!). On errors, e.g. if the child
-	 * process can't be forked, this functions returns NULL. */
-
-	RES_STAT *s;
-	int pid;
+	int pipefd[2];
+	pid_t pid;
 
-	s = New_Res_Stat( );
-	if( ! s ) return NULL;
+	assert(s != NULL);
 
-	/* Fork sub-process */
-	pid = fork( );
-	if( pid > 0 )
-	{
-		close( s->pipe[1] );
+	pid = Resolver_fork(pipefd);
+	if (pid > 0) {
 		/* Main process */
+#ifdef DEBUG
 		Log( LOG_DEBUG, "Resolver for \"%s\" created (PID %d).", Host, pid );
-		if (!io_setnonblock( s->pipe[0] )) {
-			Log( LOG_DEBUG, "Could not set Non-Blocking mode for pipefd %d", s->pipe[0] );
-			goto out;
-		}
-		if (!io_event_create( s->pipe[0], IO_WANTREAD, cb_resolver )) {
-			Log( LOG_DEBUG, "Could not add pipefd %dto event watchlist: %s",
-								s->pipe[0], strerror(errno) );
-			goto out;
-		}
+#endif
 		s->pid = pid;
-		return s;
-	}
-	else if( pid == 0 )
-	{
-		close( s->pipe[0] );
+		s->resolver_fd = pipefd[0];
+		return register_callback(s, cbfunc);
+	} else if( pid == 0 ) {
 		/* Sub process */
-		Log_Init_Resolver( );
-		Do_ResolveName( Host, s->pipe[1] );
+		Do_ResolveName(Host, pipefd[1]);
 		Log_Exit_Resolver( );
-		exit( 0 );
+		exit(0);
 	}
+	return false;
+} /* Resolve_Name */
 
-	Log( LOG_CRIT, "Resolver: Can't fork: %s!", strerror( errno ));
 
-out: /* Error! */
-	close( s->pipe[0] );
-	free( s );
-	return NULL;
-} /* Resolve_Name */
+GLOBAL void
+Resolve_Init(RES_STAT *s)
+{
+	assert(s != NULL);
+	s->resolver_fd = -1;
+	s->pid = 0;
+}
 
 
-#ifdef IDENTAUTH
-LOCAL void
-Do_ResolveAddr( struct sockaddr_in *Addr, int Sock, int w_fd )
-#else
-LOCAL void
-Do_ResolveAddr( struct sockaddr_in *Addr, int w_fd )
-#endif
+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. */
 
 	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 ) strlcpy( hostname, h->h_name, sizeof( hostname ));
-	else
-	{
+	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	
 		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 );
 
-	/* Write resolver result into pipe to parent */
 	len = strlen( hostname ); 
 	hostname[len] = '\n'; len++;
-	if( (size_t)write( w_fd, hostname, len ) != (size_t)len )
-	{
-		Log_Resolver( LOG_CRIT, "Resolver: Can't write to parent: %s!", strerror( errno ));
+	if (!array_copyb(&resolved_addr, hostname, len )) {
+		Log_Resolver( LOG_CRIT, "Resolver: Can't copy resolved name: %s!", strerror( errno ));
 		close( w_fd );
 		return;
 	}
 
 #ifdef IDENTAUTH
-	/* Do "IDENT" (aka "AUTH") lookup and write result to parent */
-	Log_Resolver( LOG_DEBUG, "Doing IDENT lookup on socket %d ...", Sock );
-	res = ident_id( Sock, 10 );
-	Log_Resolver( LOG_DEBUG, "Ok, IDENT lookup on socket %d done: \"%s\"", Sock, res ? res : "" );
-
-	/* Write IDENT result into pipe to parent */
-	if (res) {
-		len = strlen(res);
-		res[len] = '\n';
-		len++;
-	} else len = 1;
-
-	if( (size_t)write( w_fd, res ? res : "\n", len ) != (size_t)len )
-	{
-		Log_Resolver( LOG_CRIT, "Resolver: Can't write to parent (IDENT): %s!", strerror( errno ));
-		close( w_fd );
+	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);
 	}
-	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-process: resolve name and write result into pipe
 	 * to parent. */
@@ -248,33 +246,30 @@ Do_ResolveName( char *Host, int w_fd )
 	char ip[16];
 	struct hostent *h;
 	struct in_addr *addr;
-	int len;
+	size_t len;
 
 	Log_Resolver( LOG_DEBUG, "Now resolving \"%s\" ...", Host );
 
 	/* Resolve hostname */
 	h = gethostbyname( Host );
-	if( h )
-	{
+	if( h ) {
 		addr = (struct in_addr *)h->h_addr;
 		strlcpy( ip, inet_ntoa( *addr ), sizeof( ip ));
-	}
-	else
-	{
+	} 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
-		ip[0] = '\0';
+		close(w_fd);
+		return;
 	}
-	if( ip[0] ) Log_Resolver( LOG_DEBUG, "Ok, translated \"%s\" to %s.", Host, ip );
-
+#ifdef DEBUG
+	Log_Resolver( LOG_DEBUG, "Ok, translated \"%s\" to %s.", Host, ip );
+#endif
 	/* Write result into pipe to parent */
 	len = strlen( ip );
-	ip[len] = '\n'; len++;
-	if( (size_t)write( w_fd, ip, len ) != (size_t)len )
-	{
+	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 );
 	}
@@ -283,7 +278,7 @@ Do_ResolveName( char *Host, int w_fd )
 
 #ifdef h_errno
 
-LOCAL char *
+static char *
 Get_Error( int H_Error )
 {
 	/* Get error message for H_Error */
@@ -306,33 +301,65 @@ Get_Error( int H_Error )
 #endif
 
 
-LOCAL RES_STAT *
-New_Res_Stat( void )
+static bool
+register_callback( RES_STAT *s, void (*cbfunc)(int, short))
 {
-	RES_STAT *s;
+	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;
+}
 
-	/* Allocate memory */
-	s = (RES_STAT *)malloc( sizeof( RES_STAT ));
-	if( ! s )
-	{
-		Log( LOG_EMERG, "Resolver: Can't allocate memory! [Resolve_Addr]" );
-		return NULL;
-	}
 
-	/* Initialize pipe for result */
-	if( pipe( s->pipe ) != 0 )
-	{
-		free( s );
-		Log( LOG_ALERT, "Resolver: Can't create output pipe: %s!", strerror( errno ));
-		return NULL;
-	}
+GLOBAL bool
+Resolve_Shutdown( RES_STAT *s)
+{
+	bool ret = false;
+
+	assert(s != NULL);
+	assert(s->resolver_fd >= 0);
 
-	s->stage = 0;
-	s->bufpos = 0;
-	s->pid = -1;
+	if (s->resolver_fd >= 0)
+		ret = io_close(s->resolver_fd);
 
-	return s;
-} /* New_Res_Stat */
+	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- */
+