Added RERR_VANISHED.
[rsync/rsync.git] / clientname.c
index de002db..661d4ab 100644 (file)
@@ -34,6 +34,8 @@
 #include "rsync.h"
 
 static const char default_name[] = "UNKNOWN";
+extern int am_daemon;
+extern int am_server;
 
 
 /**
@@ -43,6 +45,8 @@ char *client_addr(int fd)
 {
        struct sockaddr_storage ss;
        socklen_t length = sizeof ss;
+       char *ssh_client, *p;
+       int len;
        static char addr_buf[100];
        static int initialised;
 
@@ -50,11 +54,25 @@ char *client_addr(int fd)
 
        initialised = 1;
 
-       client_sockaddr(fd, &ss, &length);
+       if (am_server) {
+               /* daemon over --rsh mode */
+               strcpy(addr_buf, "0.0.0.0");
+               if ((ssh_client = getenv("SSH_CLIENT")) != NULL) {
+                       /* truncate SSH_CLIENT to just IP address */
+                       p = strchr(ssh_client, ' ');
+                       if (p) {
+                               len = MIN((unsigned int) (p - ssh_client), 
+                                               sizeof(addr_buf) - 1);
+                               strncpy(addr_buf, ssh_client, len);
+                               *(addr_buf + len) = '\0';
+                       }
+               }
+       } else {
+               client_sockaddr(fd, &ss, &length);
+               getnameinfo((struct sockaddr *)&ss, length,
+                           addr_buf, sizeof addr_buf, NULL, 0, NI_NUMERICHOST);
+       }
 
-       getnameinfo((struct sockaddr *)&ss, length,
-                   addr_buf, sizeof(addr_buf), NULL, 0, NI_NUMERICHOST);
-       
        return addr_buf;
 }
 
@@ -74,24 +92,67 @@ static int get_sockaddr_family(const struct sockaddr_storage *ss)
  * If anything goes wrong, including the name->addr->name check, then
  * we just use "UNKNOWN", so you can use that value in hosts allow
  * lines.
+ *
+ * After translation from sockaddr to name we do a forward lookup to
+ * make sure nobody is spoofing PTR records.
  **/
 char *client_name(int fd)
 {
-       struct sockaddr_storage ss;
-       socklen_t ss_len = sizeof ss;
        static char name_buf[100];
        static char port_buf[100];
        static int initialised;
+       struct sockaddr_storage ss, *ssp;
+       struct sockaddr_in sin;
+#ifdef INET6
+       struct sockaddr_in6 sin6;
+#endif
+       socklen_t ss_len;
 
        if (initialised) return name_buf;
 
        strcpy(name_buf, default_name);
        initialised = 1;
 
-       client_sockaddr(fd, &ss, &ss_len);
+       if (am_server) {
+               /* daemon over --rsh mode */
+
+               char *addr = client_addr(fd);
+#ifdef INET6
+               int dots = 0;
+               char *p;
+
+               for (p = addr; *p && (dots <= 3); p++) {
+                   if (*p == '.')
+                       dots++;
+               }
+               if (dots > 3) {
+                       /* more than 4 parts to IP address, must be ipv6 */
+                       ssp = (struct sockaddr_storage *) &sin6;
+                       ss_len = sizeof sin6;
+                       memset(ssp, 0, ss_len);
+                       inet_pton(AF_INET6, addr, &sin6.sin6_addr);
+                       sin6.sin6_family = AF_INET6;
+               } else
+#endif
+               {
+                       ssp = (struct sockaddr_storage *) &sin;
+                       ss_len = sizeof sin;
+                       memset(ssp, 0, ss_len);
+                       inet_pton(AF_INET, addr, &sin.sin_addr);
+                       sin.sin_family = AF_INET;
+               }
+
+       } else {
+               ss_len = sizeof ss;
+               ssp = &ss;
+
+               client_sockaddr(fd, &ss, &ss_len);
+
+       }
 
-       if (!lookup_name(fd, &ss, ss_len, name_buf, sizeof name_buf, port_buf, sizeof port_buf))
-               check_name(fd, &ss, ss_len, name_buf, port_buf);
+       if (!lookup_name(fd, ssp, ss_len, name_buf, sizeof name_buf, 
+                       port_buf, sizeof port_buf))
+               check_name(fd, ssp, name_buf);
 
        return name_buf;
 }
@@ -108,6 +169,8 @@ void client_sockaddr(int fd,
                     struct sockaddr_storage *ss,
                     socklen_t *ss_len)
 {
+       memset(ss, 0, sizeof(*ss));
+
        if (getpeername(fd, (struct sockaddr *) ss, ss_len)) {
                /* FIXME: Can we really not continue? */
                rprintf(FERROR, RSYNC_NAME ": getpeername on fd%d failed: %s\n",
@@ -149,6 +212,8 @@ void client_sockaddr(int fd,
 
 /**
  * Look up a name from @p ss into @p name_buf.
+ *
+ * @param fd file descriptor for client socket.
  **/
 int lookup_name(int fd, const struct sockaddr_storage *ss,
                socklen_t ss_len,
@@ -175,27 +240,89 @@ int lookup_name(int fd, const struct sockaddr_storage *ss,
 
 
 
+/**
+ * Compare an addrinfo from the resolver to a sockinfo.
+ *
+ * Like strcmp, returns 0 for identical.
+ **/
+int compare_addrinfo_sockaddr(const struct addrinfo *ai,
+                             const struct sockaddr_storage *ss)
+{
+       int ss_family = get_sockaddr_family(ss);
+       const char fn[] = "compare_addrinfo_sockaddr";
+                     
+       if (ai->ai_family != ss_family) {
+               rprintf(FERROR,
+                       "%s: response family %d != %d\n",
+                       fn, ai->ai_family, ss_family);
+               return 1;
+       }
+
+       /* The comparison method depends on the particular AF. */
+       if (ss_family == AF_INET) {
+               const struct sockaddr_in *sin1, *sin2;
+
+               sin1 = (const struct sockaddr_in *) ss;
+               sin2 = (const struct sockaddr_in *) ai->ai_addr;
+               
+               return memcmp(&sin1->sin_addr, &sin2->sin_addr,
+                             sizeof sin1->sin_addr);
+       }
+#ifdef INET6
+       else if (ss_family == AF_INET6) {
+               const struct sockaddr_in6 *sin1, *sin2;
+
+               sin1 = (const struct sockaddr_in6 *) ss;
+               sin2 = (const struct sockaddr_in6 *) ai->ai_addr;
+
+               if (ai->ai_addrlen < sizeof(struct sockaddr_in6)) {
+                       rprintf(FERROR,
+                               "%s: too short sockaddr_in6; length=%d\n",
+                               fn, ai->ai_addrlen);
+                       return 1;
+               }
+
+               if (memcmp(&sin1->sin6_addr, &sin2->sin6_addr,
+                          sizeof sin1->sin6_addr))
+                       return 1;
+
+#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
+               if (sin1->sin6_scope_id != sin2->sin6_scope_id)
+                       return 1;
+#endif
+               return 0;
+       }
+#endif /* INET6 */
+       else {
+               /* don't know */
+               return 1;
+       }
+}
+
+
 /**
  * Do a forward lookup on @p name_buf and make sure it corresponds to
  * @p ss -- otherwise we may be being spoofed.  If we suspect we are,
  * then we don't abort the connection but just emit a warning, and
  * change @p name_buf to be "UNKNOWN".
+ *
+ * We don't do anything with the service when checking the name,
+ * because it doesn't seem that it could be spoofed in any way, and
+ * getaddrinfo on random service names seems to cause problems on AIX.
  **/
 int check_name(int fd,
               const struct sockaddr_storage *ss,
-              socklen_t ss_len,
-              char *name_buf,
-              const char *port_buf)
+              char *name_buf)
 {
        struct addrinfo hints, *res, *res0;
        int error;
        int ss_family = get_sockaddr_family(ss);
 
        memset(&hints, 0, sizeof(hints));
-       hints.ai_family = PF_UNSPEC;
-       hints.ai_flags = ss_family;
+       hints.ai_family = ss_family;
+       hints.ai_flags = AI_CANONNAME;
        hints.ai_socktype = SOCK_STREAM;
-       error = getaddrinfo(name_buf, port_buf, &hints, &res0);
+       error = getaddrinfo(name_buf, NULL, &hints, &res0);
        if (error) {
                rprintf(FERROR,
                        RSYNC_NAME ": forward name lookup for %s failed: %s\n",
@@ -205,30 +332,11 @@ int check_name(int fd,
        }
 
 
-       /* We expect that one of the results will be the same as ss. */
+       /* Given all these results, we expect that one of them will be
+        * the same as ss.  The comparison is a bit complicated. */
        for (res = res0; res; res = res->ai_next) {
-               if (res->ai_family != ss_family) {
-                       rprintf(FERROR,
-                               "check_name: response family %d != %d\n",
-                               res->ai_family, ss_family);
-                       continue;
-               }
-               if (res->ai_addrlen != ss_len) {
-                       rprintf(FERROR,
-                               "check_name: addrlen %d != %d\n",
-                               res->ai_addrlen, ss_len);
-                       continue;
-               }
-               if (memcmp(res->ai_addr, ss, res->ai_addrlen) == 0) {
-                       rprintf(FERROR,
-                               "check_name: %d bytes of address identical\n",
-                               res->ai_addrlen);
-                       break;
-               } else{
-                       rprintf(FERROR,
-                               "check_name: %d bytes of address NOT identical\n",
-                               res->ai_addrlen);
-               }
+               if (!compare_addrinfo_sockaddr(res, ss))
+                       break;  /* OK, identical */
        }
 
        if (!res0) {
@@ -239,8 +347,7 @@ int check_name(int fd,
                        "spoofed address?\n",
                        name_buf);
                strcpy(name_buf, default_name);
-       }
-       if (res == NULL) {
+       } else if (res == NULL) {
                /* We hit the end of the list without finding an
                 * address that was the same as ss. */
                rprintf(FERROR, RSYNC_NAME