]> andersk Git - openssh.git/blobdiff - channels.c
- (tim) [configure.ac] Bug 1078. Fix --without-kerberos5. Reported by
[openssh.git] / channels.c
index ac35293d474518be3b2c29b30129eac8d7b22efc..8c7b2b369000a3c806b8adb77b8dfd374c1556f6 100644 (file)
@@ -39,7 +39,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: channels.c,v 1.210 2004/08/23 11:48:47 djm Exp $");
+RCSID("$OpenBSD: channels.c,v 1.223 2005/07/17 07:17:54 djm Exp $");
 
 #include "ssh.h"
 #include "ssh1.h"
@@ -58,6 +58,8 @@ RCSID("$OpenBSD: channels.c,v 1.210 2004/08/23 11:48:47 djm Exp $");
 
 /* -- channel core */
 
+#define CHAN_RBUF      16*1024
+
 /*
  * Pointer to an array containing all allocated channels.  The array is
  * dynamically extended as needed.
@@ -109,6 +111,9 @@ static int all_opens_permitted = 0;
 /* Maximum number of fake X11 displays to try. */
 #define MAX_DISPLAYS  1000
 
+/* Saved X11 local (client) display. */
+static char *x11_saved_display = NULL;
+
 /* Saved X11 authentication protocol name. */
 static char *x11_saved_proto = NULL;
 
@@ -712,6 +717,9 @@ channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset)
 {
        u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
 
+       /* check buffer limits */
+       limit = MIN(limit, (BUFFER_MAX_LEN - BUFFER_MAX_CHUNK - CHAN_RBUF));
+
        if (c->istate == CHAN_INPUT_OPEN &&
            limit > 0 &&
            buffer_len(&c->input) < limit)
@@ -722,8 +730,8 @@ channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset)
                        FD_SET(c->wfd, writeset);
                } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
                        if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
-                              debug2("channel %d: obuf_empty delayed efd %d/(%d)",
-                                  c->self, c->efd, buffer_len(&c->extended));
+                               debug2("channel %d: obuf_empty delayed efd %d/(%d)",
+                                   c->self, c->efd, buffer_len(&c->extended));
                        else
                                chan_obuf_empty(c);
                }
@@ -889,7 +897,7 @@ static int
 channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
 {
        char *p, *host;
-       int len, have, i, found;
+       u_int len, have, i, found;
        char username[256];
        struct {
                u_int8_t version;
@@ -974,7 +982,7 @@ channel_decode_socks5(Channel *c, fd_set * readset, fd_set * writeset)
        } s5_req, s5_rsp;
        u_int16_t dest_port;
        u_char *p, dest_addr[255+1];
-       int i, have, found, nmethods, addrlen, af;
+       u_int have, i, found, nmethods, addrlen, af;
 
        debug2("channel %d: decode socks5", c->self);
        p = buffer_ptr(&c->input);
@@ -1018,7 +1026,7 @@ channel_decode_socks5(Channel *c, fd_set * readset, fd_set * writeset)
                debug2("channel %d: only socks5 connect supported", c->self);
                return -1;
        }
-       switch(s5_req.atyp){
+       switch (s5_req.atyp){
        case SSH_SOCKS5_IPV4:
                addrlen = 4;
                af = AF_INET;
@@ -1070,7 +1078,8 @@ static void
 channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
 {
        u_char *p;
-       int have, ret;
+       u_int have;
+       int ret;
 
        have = buffer_len(&c->input);
        c->delayed = 0;
@@ -1173,7 +1182,7 @@ port_open_helper(Channel *c, char *rtype)
        int direct;
        char buf[1024];
        char *remote_ipaddr = get_peer_ipaddr(c->sock);
-       u_short remote_port = get_peer_port(c->sock);
+       int remote_port = get_peer_port(c->sock);
 
        direct = (strcmp(rtype, "direct-tcpip") == 0);
 
@@ -1203,7 +1212,7 @@ port_open_helper(Channel *c, char *rtype)
                }
                /* originator host and port */
                packet_put_cstring(remote_ipaddr);
-               packet_put_int(remote_port);
+               packet_put_int((u_int)remote_port);
                packet_send();
        } else {
                packet_start(SSH_MSG_PORT_OPEN);
@@ -1360,7 +1369,7 @@ channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
 static int
 channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
 {
-       char buf[16*1024];
+       char buf[CHAN_RBUF];
        int len;
 
        if (c->rfd != -1 &&
@@ -1454,7 +1463,7 @@ channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
 static int
 channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
 {
-       char buf[16*1024];
+       char buf[CHAN_RBUF];
        int len;
 
 /** XXX handle drain efd, too */
@@ -1804,8 +1813,8 @@ channel_output_poll(void)
                         * hack for extended data: delay EOF if EFD still in use.
                         */
                        if (CHANNEL_EFD_INPUT_ACTIVE(c))
-                              debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
-                                  c->self, c->efd, buffer_len(&c->extended));
+                               debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
+                                   c->self, c->efd, buffer_len(&c->extended));
                        else
                                chan_ibuf_empty(c);
                }
@@ -2179,35 +2188,77 @@ channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_por
     const char *host_to_connect, u_short port_to_connect, int gateway_ports)
 {
        Channel *c;
-       int success, sock, on = 1;
+       int sock, r, success = 0, on = 1, wildcard = 0, is_client;
        struct addrinfo hints, *ai, *aitop;
-       const char *host;
+       const char *host, *addr;
        char ntop[NI_MAXHOST], strport[NI_MAXSERV];
 
-       success = 0;
        host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
            listen_addr : host_to_connect;
+       is_client = (type == SSH_CHANNEL_PORT_LISTENER);
 
        if (host == NULL) {
                error("No forward host name.");
-               return success;
+               return 0;
        }
        if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
                error("Forward host name too long.");
-               return success;
+               return 0;
        }
 
+       /*
+        * Determine whether or not a port forward listens to loopback,
+        * specified address or wildcard. On the client, a specified bind
+        * address will always override gateway_ports. On the server, a
+        * gateway_ports of 1 (``yes'') will override the client's
+        * specification and force a wildcard bind, whereas a value of 2
+        * (``clientspecified'') will bind to whatever address the client
+        * asked for.
+        *
+        * Special-case listen_addrs are:
+        *
+        * "0.0.0.0"               -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
+        * "" (empty string), "*"  -> wildcard v4/v6
+        * "localhost"             -> loopback v4/v6
+        */
+       addr = NULL;
+       if (listen_addr == NULL) {
+               /* No address specified: default to gateway_ports setting */
+               if (gateway_ports)
+                       wildcard = 1;
+       } else if (gateway_ports || is_client) {
+               if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
+                   strcmp(listen_addr, "0.0.0.0") == 0) ||
+                   *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
+                   (!is_client && gateway_ports == 1))
+                       wildcard = 1;
+               else if (strcmp(listen_addr, "localhost") != 0)
+                       addr = listen_addr;
+       }
+
+       debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
+           type, wildcard, (addr == NULL) ? "NULL" : addr);
+
        /*
         * getaddrinfo returns a loopback address if the hostname is
         * set to NULL and hints.ai_flags is not AI_PASSIVE
         */
        memset(&hints, 0, sizeof(hints));
        hints.ai_family = IPv4or6;
-       hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
+       hints.ai_flags = wildcard ? AI_PASSIVE : 0;
        hints.ai_socktype = SOCK_STREAM;
        snprintf(strport, sizeof strport, "%d", listen_port);
-       if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
-               packet_disconnect("getaddrinfo: fatal error");
+       if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
+               if (addr == NULL) {
+                       /* This really shouldn't happen */
+                       packet_disconnect("getaddrinfo: fatal error: %s",
+                           gai_strerror(r));
+               } else {
+                       error("channel_setup_fwd_listener: "
+                           "getaddrinfo(%.64s): %s", addr, gai_strerror(r));
+               }
+               return 0;
+       }
 
        for (ai = aitop; ai; ai = ai->ai_next) {
                if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
@@ -2273,7 +2324,7 @@ channel_cancel_rport_listener(const char *host, u_short port)
        u_int i;
        int found = 0;
 
-       for(i = 0; i < channels_alloc; i++) {
+       for (i = 0; i < channels_alloc; i++) {
                Channel *c = channels[i];
 
                if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
@@ -2290,11 +2341,12 @@ channel_cancel_rport_listener(const char *host, u_short port)
 
 /* protocol local port fwd, used by ssh (and sshd in v1) */
 int
-channel_setup_local_fwd_listener(u_short listen_port,
+channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
     const char *host_to_connect, u_short port_to_connect, int gateway_ports)
 {
        return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
-           NULL, listen_port, host_to_connect, port_to_connect, gateway_ports);
+           listen_host, listen_port, host_to_connect, port_to_connect,
+           gateway_ports);
 }
 
 /* protocol v2 remote port fwd, used by sshd */
@@ -2312,7 +2364,7 @@ channel_setup_remote_fwd_listener(const char *listen_address,
  */
 
 void
-channel_request_remote_forwarding(u_short listen_port,
+channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
     const char *host_to_connect, u_short port_to_connect)
 {
        int type, success = 0;
@@ -2323,7 +2375,14 @@ channel_request_remote_forwarding(u_short listen_port,
 
        /* Send the forward request to the remote side. */
        if (compat20) {
-               const char *address_to_bind = "0.0.0.0";
+               const char *address_to_bind;
+               if (listen_host == NULL)
+                       address_to_bind = "localhost";
+               else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0)
+                       address_to_bind = "";
+               else
+                       address_to_bind = listen_host;
+
                packet_start(SSH2_MSG_GLOBAL_REQUEST);
                packet_put_cstring("tcpip-forward");
                packet_put_char(1);                     /* boolean: want reply */
@@ -2369,10 +2428,9 @@ channel_request_remote_forwarding(u_short listen_port,
  * local side.
  */
 void
-channel_request_rforward_cancel(u_short port)
+channel_request_rforward_cancel(const char *host, u_short port)
 {
        int i;
-       const char *address_to_bind = "0.0.0.0";
 
        if (!compat20)
                return;
@@ -2389,7 +2447,7 @@ channel_request_rforward_cancel(u_short port)
        packet_start(SSH2_MSG_GLOBAL_REQUEST);
        packet_put_cstring("cancel-tcpip-forward");
        packet_put_char(0);
-       packet_put_cstring(address_to_bind);
+       packet_put_cstring(host == NULL ? "" : host);
        packet_put_int(port);
        packet_send();
 
@@ -2430,7 +2488,8 @@ channel_input_port_forward_request(int is_root, int gateway_ports)
 #endif
 
        /* Initiate forwarding */
-       channel_setup_local_fwd_listener(port, hostname, host_port, gateway_ports);
+       channel_setup_local_fwd_listener(NULL, port, hostname,
+           host_port, gateway_ports);
 
        /* Free the argument string. */
        xfree(hostname);
@@ -2577,7 +2636,7 @@ channel_send_window_changes(void)
        struct winsize ws;
 
        for (i = 0; i < channels_alloc; i++) {
-               if (channels[i] == NULL ||
+               if (channels[i] == NULL || !channels[i]->client_tty ||
                    channels[i]->type != SSH_CHANNEL_OPEN)
                        continue;
                if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
@@ -2600,7 +2659,7 @@ channel_send_window_changes(void)
  */
 int
 x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
-    int single_connection, u_int *display_numberp)
+    int single_connection, u_int *display_numberp, int **chanids)
 {
        Channel *nc = NULL;
        int display_number, sock;
@@ -2690,6 +2749,8 @@ x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
        }
 
        /* Allocate a channel for each socket. */
+       if (chanids != NULL)
+               *chanids = xmalloc(sizeof(**chanids) * (num_socks + 1));
        for (n = 0; n < num_socks; n++) {
                sock = socks[n];
                nc = channel_new("x11 listener",
@@ -2697,7 +2758,11 @@ x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
                    CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
                    0, "X11 inet listener", 1);
                nc->single_connection = single_connection;
+               if (*chanids != NULL)
+                       (*chanids)[n] = nc->self;
        }
+       if (*chanids != NULL)
+               (*chanids)[n] = -1;
 
        /* Return the display number for the DISPLAY environment variable. */
        *display_numberp = display_number;
@@ -2895,19 +2960,27 @@ deny_input_open(int type, u_int32_t seq, void *ctxt)
  * This should be called in the client only.
  */
 void
-x11_request_forwarding_with_spoofing(int client_session_id,
+x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
     const char *proto, const char *data)
 {
        u_int data_len = (u_int) strlen(data) / 2;
-       u_int i, value, len;
+       u_int i, value;
        char *new_data;
        int screen_number;
        const char *cp;
        u_int32_t rnd = 0;
 
-       cp = getenv("DISPLAY");
-       if (cp)
-               cp = strchr(cp, ':');
+       if (x11_saved_display == NULL)
+               x11_saved_display = xstrdup(disp);
+       else if (strcmp(disp, x11_saved_display) != 0) {
+               error("x11_request_forwarding_with_spoofing: different "
+                   "$DISPLAY already forwarded");
+               return;
+       }
+
+       cp = disp;
+       if (disp)
+               cp = strchr(disp, ':');
        if (cp)
                cp = strchr(cp, '.');
        if (cp)
@@ -2915,33 +2988,31 @@ x11_request_forwarding_with_spoofing(int client_session_id,
        else
                screen_number = 0;
 
-       /* Save protocol name. */
-       x11_saved_proto = xstrdup(proto);
-
-       /*
-        * Extract real authentication data and generate fake data of the
-        * same length.
-        */
-       x11_saved_data = xmalloc(data_len);
-       x11_fake_data = xmalloc(data_len);
-       for (i = 0; i < data_len; i++) {
-               if (sscanf(data + 2 * i, "%2x", &value) != 1)
-                       fatal("x11_request_forwarding: bad authentication data: %.100s", data);
-               if (i % 4 == 0)
-                       rnd = arc4random();
-               x11_saved_data[i] = value;
-               x11_fake_data[i] = rnd & 0xff;
-               rnd >>= 8;
-       }
-       x11_saved_data_len = data_len;
-       x11_fake_data_len = data_len;
+       if (x11_saved_proto == NULL) {
+               /* Save protocol name. */
+               x11_saved_proto = xstrdup(proto);
+               /*
+                * Extract real authentication data and generate fake data
+                * of the same length.
+                */
+               x11_saved_data = xmalloc(data_len);
+               x11_fake_data = xmalloc(data_len);
+               for (i = 0; i < data_len; i++) {
+                       if (sscanf(data + 2 * i, "%2x", &value) != 1)
+                               fatal("x11_request_forwarding: bad "
+                                   "authentication data: %.100s", data);
+                       if (i % 4 == 0)
+                               rnd = arc4random();
+                       x11_saved_data[i] = value;
+                       x11_fake_data[i] = rnd & 0xff;
+                       rnd >>= 8;
+               }
+               x11_saved_data_len = data_len;
+               x11_fake_data_len = data_len;
+       }
 
        /* Convert the fake data into hex. */
-       len = 2 * data_len + 1;
-       new_data = xmalloc(len);
-       for (i = 0; i < data_len; i++)
-               snprintf(new_data + 2 * i, len - 2 * i,
-                   "%02x", (u_char) x11_fake_data[i]);
+       new_data = tohex(x11_fake_data, data_len);
 
        /* Send the request packet. */
        if (compat20) {
This page took 0.068093 seconds and 4 git commands to generate.