+++ /dev/null
-/*
- * $Id$
- *
- * locate the originating host
- *
- */
-
-#include "sysdep.h"
-#include <stdlib.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <ctype.h>
-#include <signal.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <limits.h>
-#include <netdb.h>
-#include <string.h>
-#include "citadel.h"
-#include "server.h"
-#include "serv_extensions.h"
-#include "locate_host.h"
-#include "sysdep_decls.h"
-#include "config.h"
-#include "tools.h"
-#include "domain.h"
-
-#ifdef HAVE_RESOLV_H
-#include <arpa/nameser.h>
-#ifdef HAVE_ARPA_NAMESER_COMPAT_H
-#include <arpa/nameser_compat.h>
-#endif
-#include <resolv.h>
-#endif
-
-
-/* Hacks to work around nameser.h declarations missing on OpenBSD
- * see also: http://search.cpan.org/src/MIKER/Net-DNS-ToolKit-0.30/ToolKit.h
- */
-
-#ifndef NS_INT16SZ
-# ifdef INT16SZ
-# define NS_INT16SZ INT16SZ
-# endif
-#endif
-
-#ifndef NS_INT32SZ
-# ifdef INT32SZ
-# define NS_INT32SZ INT32SZ
-# endif
-#endif
-
-#ifndef NS_GET16
-# ifdef GETSHORT
-# define NS_GET16 GETSHORT
-# endif
-#endif
-
-
-/***************************************************************************/
-
-
-void locate_host(char *tbuf, size_t n,
- char *abuf, size_t na,
- const struct in_addr *addr)
-{
- struct hostent *ch;
- const char *i;
- char *j;
- int a1, a2, a3, a4;
- char address_string[SIZ];
-
-
-#ifdef HAVE_NONREENTRANT_NETDB
- begin_critical_section(S_NETDB);
-#endif
-
- i = (const char *) addr;
- a1 = ((*i++) & 0xff);
- a2 = ((*i++) & 0xff);
- a3 = ((*i++) & 0xff);
- a4 = ((*i++) & 0xff);
- sprintf(address_string, "%d.%d.%d.%d", a1, a2, a3, a4);
-
- if (abuf != NULL) {
- safestrncpy(abuf, address_string, na);
- }
-
- if ((ch = gethostbyaddr((const char *) addr,
- sizeof(*addr), AF_INET)) == NULL) {
-bad_dns:
- safestrncpy(tbuf, address_string, n);
- goto end; /* because we might need to end the critical
- section */
- }
- /* check if the forward DNS agrees; if not, they're spoofing */
- j = strdup(ch->h_name);
- ch = gethostbyname(j);
- free(j);
- if (ch == NULL)
- goto bad_dns;
-
- /* check address for consistency */
- for (; *ch->h_addr_list; ch->h_addr_list++)
- if (!memcmp(*ch->h_addr_list, addr,
- sizeof *addr)) {
- safestrncpy(tbuf, ch->h_name, 63);
- goto end;
- }
- goto bad_dns; /* they were spoofing. report a numeric IP
- address. */
-
- end:
-
-#ifdef HAVE_NONREENTRANT_NETDB
- end_critical_section(S_NETDB);
-#endif
-
- tbuf[63] = 0;
-}
-
-
-/*
- * RBL check written by Edward S. Marshall [http://rblcheck.sourceforge.net]
- */
-#define RESULT_SIZE 4096 /* What is the longest result text we support? */
-int rblcheck_backend(char *domain, char *txtbuf, int txtbufsize) {
- int a, b, c;
- char *result = NULL;
- u_char fixedans[ PACKETSZ ];
- u_char *answer;
- int need_to_free_answer = 0;
- const u_char *cp;
- u_char *rp;
- const u_char *cend;
- const u_char *rend;
- int len;
- char *p = NULL;
-
- /* Make our DNS query. */
- //res_init();
- answer = fixedans;
- len = res_query( domain, C_IN, T_A, answer, PACKETSZ );
-
- /* Was there a problem? If so, the domain doesn't exist. */
- if( len == -1 ) {
- if (txtbuf != NULL) {
- strcpy(txtbuf, "");
- }
- return(0);
- }
-
- if( len > PACKETSZ )
- {
- answer = malloc( len );
- need_to_free_answer = 1;
- len = res_query( domain, C_IN, T_A, answer, len );
- if( len == -1 ) {
- if (txtbuf != NULL) {
- snprintf(txtbuf, txtbufsize,
- "Message rejected due to known spammer source IP address");
- }
- if (need_to_free_answer) free(answer);
- return(1);
- }
- }
-
- result = ( char * )malloc( RESULT_SIZE );
- result[ 0 ] = '\0';
-
-
- /* Make another DNS query for textual data; this shouldn't
- be a performance hit, since it'll now be cached at the
- nameserver we're using. */
- res_init();
- len = res_query( domain, C_IN, T_TXT, answer, PACKETSZ );
-
- /* Just in case there's no TXT record... */
- if( len == -1 )
- {
- if (txtbuf != NULL) {
- snprintf(txtbuf, txtbufsize,
- "Message rejected due to known spammer source IP address");
- }
- if (need_to_free_answer) free(answer);
- free(result);
- return(1);
- }
-
- /* Skip the header and the address we queried. */
- cp = answer + sizeof( HEADER );
- while( *cp != '\0' )
- {
- a = *cp++;
- while( a-- )
- cp++;
- }
-
- /* This seems to be a bit of magic data that we need to
- skip. I wish there were good online documentation
- for programming for libresolv, so I'd know what I'm
- skipping here. Anyone reading this, feel free to
- enlighten me. */
- cp += 1 + NS_INT16SZ + NS_INT32SZ;
-
- /* Skip the type, class and ttl. */
- cp += ( NS_INT16SZ * 2 ) + NS_INT32SZ;
-
- /* Get the length and end of the buffer. */
- NS_GET16( c, cp );
- cend = cp + c;
-
- /* Iterate over any multiple answers we might have. In
- this context, it's unlikely, but anyway. */
- rp = (u_char *) result;
- rend = (u_char *) result + RESULT_SIZE - 1;
- while( cp < cend && rp < rend )
- {
- a = *cp++;
- if( a != 0 )
- for( b = a; b > 0 && cp < cend && rp < rend;
- b-- )
- {
- if( *cp == '\n' || *cp == '"' ||
- *cp == '\\' )
- {
- *rp++ = '\\';
- }
- *rp++ = *cp++;
- }
- }
- *rp = '\0';
- if (txtbuf != NULL) {
- snprintf(txtbuf, txtbufsize, "%s", result);
- }
- /* Remove nonprintable characters */
- for (p=txtbuf; *p; ++p) {
- if (!isprint(*p)) strcpy(p, p+1);
- }
- if (need_to_free_answer) free(answer);
- free(result);
- return(1);
-}
-
-
-/*
- * Check to see if a host is on some sort of spam list (RBL)
- * If spammer, returns nonzero and places reason in 'message_to_spammer'
- */
-int rbl_check_addr(struct in_addr *addr, char *message_to_spammer)
-{
- const char *i;
- int a1, a2, a3, a4;
- char tbuf[256];
- int rbl;
- int num_rbl;
- char rbl_domains[SIZ];
- char txt_answer[1024];
-
- strcpy(message_to_spammer, "ok");
-
- i = (const char *) addr;
- a1 = ((*i++) & 0xff);
- a2 = ((*i++) & 0xff);
- a3 = ((*i++) & 0xff);
- a4 = ((*i++) & 0xff);
-
- /* See if we have any RBL domains configured */
- num_rbl = get_hosts(rbl_domains, "rbl");
- if (num_rbl < 1) return(0);
-
- /* Try all configured RBL's */
- for (rbl=0; rbl<num_rbl; ++rbl) {
- snprintf(tbuf, sizeof tbuf,
- "%d.%d.%d.%d.",
- a4, a3, a2, a1);
- extract_token(&tbuf[strlen(tbuf)], rbl_domains, rbl, '|', (sizeof tbuf - strlen(tbuf)));
-
- if (rblcheck_backend(tbuf, txt_answer, sizeof txt_answer)) {
- sprintf(message_to_spammer, "5.7.1 %s", txt_answer);
- lprintf(CTDL_INFO, "RBL: %s\n", txt_answer);
- return(1);
- }
- }
-
- return(0);
-}
-
-
-/*
- * Check to see if the client host is on some sort of spam list (RBL)
- * If spammer, returns nonzero and places reason in 'message_to_spammer'
- */
-int rbl_check(char *message_to_spammer) {
- struct sockaddr_in sin;
- int len; /* should be socklen_t but doesn't work on Macintosh */
-
- if (!getpeername(CC->client_socket, (struct sockaddr *) &sin, (socklen_t *)&len)) {
- return(rbl_check_addr(&sin.sin_addr, message_to_spammer));
- }
- return(0);
-}
-
-/*
- * Convert a host name to a dotted quad address.
- * Returns zero on success or nonzero on failure.
- */
-int hostname_to_dotted_quad(char *addr, char *host) {
- struct hostent *ch;
- const char *i;
- int a1, a2, a3, a4;
-
- ch = gethostbyname(host);
- if (ch == NULL) {
- strcpy(addr, "0.0.0.0");
- return(1);
- }
-
- i = (const char *) ch->h_addr_list[0];
- a1 = ((*i++) & 0xff);
- a2 = ((*i++) & 0xff);
- a3 = ((*i++) & 0xff);
- a4 = ((*i++) & 0xff);
- sprintf(addr, "%d.%d.%d.%d", a1, a2, a3, a4);
- return(0);
-}
projects / citadel.git / blobdiff