- Merged OpenBSD IPv6 patch:

   - [sshd.c sshd.8 sshconnect.c ssh.h ssh.c servconf.h servconf.c scp.1]
     [scp.c packet.h packet.c login.c log.c canohost.c channels.c]
     [hostfile.c sshd_config]
     ipv6 support: mostly gethostbyname->getaddrinfo/getnameinfo, new
     features: sshd allows multiple ListenAddress and Port options. note
     that libwrap is not IPv6-ready. (based on patches from
     fujiwara@rcac.tdi.co.jp)
   - [ssh.c canohost.c]
     more hints (hints.ai_socktype=SOCK_STREAM) for getaddrinfo,
     from itojun@
   - [channels.c]
     listen on _all_ interfaces for X11-Fwd (hints.ai_flags = AI_PASSIVE)
   - [packet.h]
     allow auth-kerberos for IPv4 only
   - [scp.1 sshd.8 servconf.h scp.c]
     document -4, -6, and 'ssh -L 2022/::1/22'
   - [ssh.c]
     'ssh @host' is illegal (null user name), from
     karsten@gedankenpolizei.de
   - [sshconnect.c]
     better error message
   - [sshd.c]
     allow auth-kerberos for IPv4 only
 - Big IPv6 merge:
   - Cleanup overrun in sockaddr copying on RHL 6.1
   - Replacements for getaddrinfo, getnameinfo, etc based on versions
     from patch from KIKUCHI Takahiro <kick@kyoto.wide.ad.jp>
   - Replacement for missing structures on systems that lack IPv6
   - record_login needed to know about AF_INET6 addresses
   - Borrowed more code from OpenBSD: rresvport_af and requisites

1 files changed, 96 insertions, 88 deletions

diff --git a/canohost.c b/canohost.c
index edfaa94e1..9a6d8b732 100644
--- a/canohost.c
+++ b/canohost.c
@@ -14,7 +14,7 @@
  */
 
 #include "includes.h"
-RCSID("$Id: canohost.c,v 1.6 1999/12/18 09:57:40 damien Exp $");
+RCSID("$Id: canohost.c,v 1.7 2000/01/14 04:45:48 damien Exp $");
 
 #include "packet.h"
 #include "xmalloc.h"
@@ -28,10 +28,12 @@ RCSID("$Id: canohost.c,v 1.6 1999/12/18 09:57:40 damien Exp $");
 char *
 get_remote_hostname(int socket)
 {
-        struct sockaddr_in from;
-        int fromlen, i;
-        struct hostent *hp;
+        struct sockaddr_storage from;
+        int i;
+        socklen_t fromlen;
+        struct addrinfo hints, *ai, *aitop;
         char name[MAXHOSTNAMELEN];
+        char ntop[NI_MAXHOST], ntop2[NI_MAXHOST];
 
         /* Get IP address of client. */
         fromlen = sizeof(from);
@@ -40,20 +42,15 @@ get_remote_hostname(int socket)
                 debug("getpeername failed: %.100s", strerror(errno));
                 fatal_cleanup();
         }
-        /* Map the IP address to a host name. */
-        hp = gethostbyaddr((char *) &from.sin_addr, sizeof(struct in_addr),
-                           from.sin_family);
-        if (hp) {
-                /* Got host name, find canonic host name. */
-                if (strchr(hp->h_name, '.') != 0)
-                        strlcpy(name, hp->h_name, sizeof(name));
-                else if (hp->h_aliases != 0
-                         && hp->h_aliases[0] != 0
-                         && strchr(hp->h_aliases[0], '.') != 0)
-                        strlcpy(name, hp->h_aliases[0], sizeof(name));
-                else
-                        strlcpy(name, hp->h_name, sizeof(name));
+        if (getnameinfo((struct sockaddr *)&from, fromlen, ntop, sizeof(ntop),
+             NULL, 0, NI_NUMERICHOST) != 0)
+                fatal("get_remote_hostname: getnameinfo NI_NUMERICHOST failed");
 
+        /* Map the IP address to a host name. */
+        if (getnameinfo((struct sockaddr *)&from, fromlen, name, sizeof(name),
+             NULL, 0, NI_NAMEREQD) == 0) {
+                /* Got host name. */
+                name[sizeof(name) - 1] = '\0';
                 /*
                  * Convert it to all lowercase (which is expected by the rest
                  * of this software).
@@ -71,32 +68,34 @@ get_remote_hostname(int socket)
                  * fooled if the intruder has access to the name server of
                  * the domain).
                  */
-                hp = gethostbyname(name);
-                if (!hp) {
-                        log("reverse mapping checking gethostbyname for %.700s failed - POSSIBLE BREAKIN ATTEMPT!", name);
-                        strlcpy(name, inet_ntoa(from.sin_addr), sizeof name);
+                memset(&hints, 0, sizeof(hints));
+                hints.ai_family = from.ss_family;
+                hints.ai_socktype = SOCK_STREAM;
+                if (getaddrinfo(name, NULL, &hints, &aitop) != 0) {
+                        log("reverse mapping checking getaddrinfo for %.700s failed - POSSIBLE BREAKIN ATTEMPT!", name);
+                        strlcpy(name, ntop, sizeof name);
                         goto check_ip_options;
                 }
                 /* Look for the address from the list of addresses. */
-                for (i = 0; hp->h_addr_list[i]; i++)
-                        if (memcmp(hp->h_addr_list[i], &from.sin_addr, sizeof(from.sin_addr))
-                            == 0)
-                                break;
-                /*
-                 * If we reached the end of the list, the address was not
-                 * there.
-                 */
-                if (!hp->h_addr_list[i]) {
+                for (ai = aitop; ai; ai = ai->ai_next) {
+                        if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop2,
+                            sizeof(ntop2), NULL, 0, NI_NUMERICHOST) == 0 &&
+                            (strcmp(ntop, ntop2) == 0))
+                                        break;
+                }
+                freeaddrinfo(aitop);
+                /* If we reached the end of the list, the address was not there. */
+                if (!ai) {
                         /* Address not found for the host name. */
                         log("Address %.100s maps to %.600s, but this does not map back to the address - POSSIBLE BREAKIN ATTEMPT!",
-                            inet_ntoa(from.sin_addr), name);
-                        strlcpy(name, inet_ntoa(from.sin_addr), sizeof name);
+                            ntop, name);
+                        strlcpy(name, ntop, sizeof name);
                         goto check_ip_options;
                 }
                 /* Address was found for the host name.  We accept the host name. */
         } else {
                 /* Host name not found.  Use ascii representation of the address. */
-                strlcpy(name, inet_ntoa(from.sin_addr), sizeof name);
+                strlcpy(name, ntop, sizeof name);
                 log("Could not reverse map address %.100s.", name);
         }
 
@@ -113,10 +112,12 @@ check_ip_options:
          * rest of the interaction and could still bypass security.  So we
          * exit here if we detect any IP options.
          */
-        {
+        /* IP options -- IPv4 only */
+        if (from.ss_family == AF_INET) {
                 unsigned char options[200], *ucp;
                 char text[1024], *cp;
-                int option_size, ipproto;
+                socklen_t option_size;
+                int ipproto;
                 struct protoent *ip;
 
                 if ((ip = getprotobyname("ip")) != NULL)
@@ -125,47 +126,21 @@ check_ip_options:
                         ipproto = IPPROTO_IP;
                 option_size = sizeof(options);
                 if (getsockopt(0, ipproto, IP_OPTIONS, (char *) options,
-                               &option_size) >= 0 && option_size != 0) {
+                    &option_size) >= 0 && option_size != 0) {
                         cp = text;
                         /* Note: "text" buffer must be at least 3x as big as options. */
                         for (ucp = options; option_size > 0; ucp++, option_size--, cp += 3)
                                 sprintf(cp, " %2.2x", *ucp);
                         log("Connection from %.100s with IP options:%.800s",
-                            inet_ntoa(from.sin_addr), text);
+                            ntop, text);
                         packet_disconnect("Connection from %.100s with IP options:%.800s",
-                                          inet_ntoa(from.sin_addr), text);
+                                          ntop, text);
                 }
         }
 
         return xstrdup(name);
 }
 
-static char *canonical_host_name = NULL;
-static char *canonical_host_ip = NULL;
-
-/* Returns 1 if remote host is connected via socket, 0 if not. */
-
-int
-peer_connection_is_on_socket()
-{
-        struct sockaddr_in from;
-        int fromlen;
-        int in = packet_get_connection_in();
-        int out = packet_get_connection_out();
-
-        /* filedescriptors in and out are the same, so it's a socket */
-        if (in == out)
-                return 1;
-        fromlen = sizeof(from);
-        memset(&from, 0, sizeof(from));
-        if (getpeername(in, (struct sockaddr *) & from, &fromlen) < 0)
-                return 0;
-        if (from.sin_family != AF_INET)
-                return 0;
-
-        return 1;
-}
-
 /*
  * Return the canonical name of the host in the other side of the current
  * connection.  The host name is cached, so it is efficient to call this
@@ -175,12 +150,14 @@ peer_connection_is_on_socket()
 const char *
 get_canonical_hostname()
 {
+        static char *canonical_host_name = NULL;
+
         /* Check if we have previously retrieved this same name. */
         if (canonical_host_name != NULL)
                 return canonical_host_name;
 
         /* Get the real hostname if socket; otherwise return UNKNOWN. */
-        if (peer_connection_is_on_socket())
+        if (packet_connection_is_on_socket())
                 canonical_host_name = get_remote_hostname(packet_get_connection_in());
         else
                 canonical_host_name = xstrdup("UNKNOWN");
@@ -190,21 +167,24 @@ get_canonical_hostname()
 
 /*
  * Returns the IP-address of the remote host as a string.  The returned
- * string need not be freed.
+ * string must not be freed.
  */
 
 const char *
 get_remote_ipaddr()
 {
-        struct sockaddr_in from;
-        int fromlen, socket;
+        static char *canonical_host_ip = NULL;
+        struct sockaddr_storage from;
+        socklen_t fromlen;
+        int socket;
+        char ntop[NI_MAXHOST];
 
         /* Check whether we have chached the name. */
         if (canonical_host_ip != NULL)
                 return canonical_host_ip;
 
         /* If not a socket, return UNKNOWN. */
-        if (!peer_connection_is_on_socket()) {
+        if (!packet_connection_is_on_socket()) {
                 canonical_host_ip = xstrdup("UNKNOWN");
                 return canonical_host_ip;
         }
@@ -219,48 +199,76 @@ get_remote_ipaddr()
                 fatal_cleanup();
         }
         /* Get the IP address in ascii. */
-        canonical_host_ip = xstrdup(inet_ntoa(from.sin_addr));
+        if (getnameinfo((struct sockaddr *)&from, fromlen, ntop, sizeof(ntop),
+             NULL, 0, NI_NUMERICHOST) != 0)
+                fatal("get_remote_hostname: getnameinfo NI_NUMERICHOST failed");
+
+        canonical_host_ip = xstrdup(ntop);
 
         /* Return ip address string. */
         return canonical_host_ip;
 }
 
-/* Returns the port of the peer of the socket. */
+/* Returns the local/remote port for the socket. */
 
-int 
-get_peer_port(int sock)
+int
+get_sock_port(int sock, int local)
 {
-        struct sockaddr_in from;
-        int fromlen;
+        struct sockaddr_storage from;
+        socklen_t fromlen;
+        char strport[NI_MAXSERV];
 
         /* Get IP address of client. */
         fromlen = sizeof(from);
         memset(&from, 0, sizeof(from));
-        if (getpeername(sock, (struct sockaddr *) & from, &fromlen) < 0) {
-                debug("getpeername failed: %.100s", strerror(errno));
-                fatal_cleanup();
+        if (local) {
+                if (getsockname(sock, (struct sockaddr *)&from, &fromlen) < 0) {
+                        error("getsockname failed: %.100s", strerror(errno));
+                        return 0;
+                }
+        } else {
+                if (getpeername(sock, (struct sockaddr *) & from, &fromlen) < 0) {
+                        debug("getpeername failed: %.100s", strerror(errno));
+                        fatal_cleanup();
+                }
         }
         /* Return port number. */
-        return ntohs(from.sin_port);
+        if (getnameinfo((struct sockaddr *)&from, fromlen, NULL, 0,
+             strport, sizeof(strport), NI_NUMERICSERV) != 0)
+                fatal("get_sock_port: getnameinfo NI_NUMERICSERV failed");
+        return atoi(strport);
 }
 
-/* Returns the port number of the remote host.  */
+/* Returns remote/local port number for the current connection. */
 
 int 
-get_remote_port()
+get_port(int local)
 {
-        int socket;
-
         /*
          * If the connection is not a socket, return 65535.  This is
          * intentionally chosen to be an unprivileged port number.
          */
-        if (!peer_connection_is_on_socket())
+        if (!packet_connection_is_on_socket())
                 return 65535;
 
-        /* Get client socket. */
-        socket = packet_get_connection_in();
+        /* Get socket and return the port number. */
+        return get_sock_port(packet_get_connection_in(), local);
+}
+
+int 
+get_peer_port(int sock)
+{
+        return get_sock_port(sock, 0);
+}
 
-        /* Get and return the peer port number. */
-        return get_peer_port(socket);
+int 
+get_remote_port()
+{
+        return get_port(0);
+}
+
+int
+get_local_port()
+{
+        return get_port(1);
 }