#include "portab.h"
-static char UNUSED id[] = "$Id: resolve.c,v 1.10 2005/03/05 12:57:14 alex Exp $";
+static char UNUSED id[] = "$Id: resolve.c,v 1.24 2006/05/10 21:24:01 alex Exp $";
#include "imp.h"
#include <assert.h>
#include "exp.h"
#include "resolve.h"
+#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 ));
-
-
-GLOBAL VOID
-Resolve_Init( VOID )
+static pid_t
+Resolver_fork(int *pipefds)
{
- /* Initialize module */
+ pid_t pid;
- FD_ZERO( &Resolver_FDs );
-} /* Resolve_Init */
+ if (pipe(pipefds) != 0) {
+ Log( LOG_ALERT, "Resolver: Can't create output pipe: %s!", strerror( errno ));
+ return -1;
+ }
+ 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!). On errors, e.g. if the child process
- * can't be forked, this functions returns NULL. */
- RES_STAT *s;
- INT pid;
+/**
+ * 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;
- s = New_Res_Stat( );
- if( ! s ) return NULL;
+ assert(s != NULL);
- /* For sub-process */
- pid = fork( );
- if( pid > 0 )
- {
- /* 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 );
- 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 )
- {
+ 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 );
- }
- else
- {
- /* Error! */
- 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))
{
- /* 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 )
- {
+ 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 )
- {
+ 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 );
- }
- else
- {
- /* Error! */
- free( s );
- Log( LOG_CRIT, "Resolver: Can't fork: %s!", strerror( errno ));
- return NULL;
+ exit(0);
}
+ return false;
} /* Resolve_Name */
-#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
+GLOBAL void
+Resolve_Init(RES_STAT *s)
+{
+ assert(s != NULL);
+ s->resolver_fd = -1;
+ s->pid = 0;
+}
+
+
+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 hostname[HOST_LEN];
+ char ipstr[HOST_LEN];
struct hostent *h;
- INT len;
+ size_t len;
+ struct in_addr *addr;
+ char *ntoaptr;
+ array resolved_addr;
#ifdef IDENTAUTH
- CHAR *res;
+ char *res;
#endif
-
+ array_init(&resolved_addr);
/* Resolve IP address */
+#ifdef DEBUG
Log_Resolver( LOG_DEBUG, "Now resolving %s ...", inet_ntoa( Addr->sin_addr ));
- h = gethostbyaddr( (CHAR *)&Addr->sin_addr, sizeof( Addr->sin_addr ), AF_INET );
- if( h ) strlcpy( hostname, h->h_name, sizeof( hostname ));
- else
- {
+#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
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 */
- len = strlen( res ? res : "" );
- if( res != NULL ) res[len] = '\n';
- len++;
- 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. */
- CHAR ip[16];
+ 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 );
}
#ifdef h_errno
-LOCAL CHAR *
-Get_Error( INT H_Error )
+static char *
+Get_Error( int H_Error )
{
/* Get error message for 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);
- /* Allocate memory */
- s = (RES_STAT *)malloc( sizeof( RES_STAT ));
- if( ! s )
- {
- Log( LOG_EMERG, "Resolver: Can't allocate memory! [Resolve_Addr]" );
- return NULL;
- }
+ if (io_setnonblock(s->resolver_fd) &&
+ io_event_create(s->resolver_fd, IO_WANTREAD, cbfunc))
+ return true;
- /* 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;
- }
+ Log( LOG_CRIT, "Resolver: Could not register callback function: %s!", strerror(errno));
+ Resolve_Shutdown(s);
+ return false;
+}
+
+
+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)
+{
+ int err;
+ ssize_t bytes_read;
+
+ assert(buflen > 0);
+
+ /* Read result from pipe */
+ errno = 0;
+ bytes_read = read(s->resolver_fd, readbuf, buflen);
+ if (bytes_read < 0) {
+ if (errno != EAGAIN) {
+ err = errno;
+ Log( LOG_CRIT, "Resolver: Can't read result: %s!", strerror(err));
+ Resolve_Shutdown(s);
+ errno = err;
+ return 0;
+ }
+ return 0;
+ }
+ Resolve_Shutdown(s);
+ if (bytes_read == 0) { /* EOF: lookup failed */
+#ifdef DEBUG
+ Log( LOG_DEBUG, "Resolver: Can't read result: EOF");
+#endif
+ return 0;
+ }
+
+ return (size_t)bytes_read;
+}
/* -eof- */
+