X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/d5bb94183c032a74ba8828f78ec1d6ac584d6f04..32560f077f93eb11a8d199ada25e7f7dfec79af4:/channels.c diff --git a/channels.c b/channels.c index da6fc000..3f6db60c 100644 --- a/channels.c +++ b/channels.c @@ -13,7 +13,7 @@ * called by a name other than "ssh" or "Secure Shell". * * SSH2 support added by Markus Friedl. - * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved. + * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. * Copyright (c) 1999 Dug Song. All rights reserved. * Copyright (c) 1999 Theo de Raadt. All rights reserved. * @@ -39,14 +39,13 @@ */ #include "includes.h" -RCSID("$OpenBSD: channels.c,v 1.142 2001/12/05 03:56:39 itojun Exp $"); +RCSID("$OpenBSD: channels.c,v 1.214 2005/03/14 11:46:56 markus Exp $"); #include "ssh.h" #include "ssh1.h" #include "ssh2.h" #include "packet.h" #include "xmalloc.h" -#include "uidswap.h" #include "log.h" #include "misc.h" #include "channels.h" @@ -54,10 +53,13 @@ RCSID("$OpenBSD: channels.c,v 1.142 2001/12/05 03:56:39 itojun Exp $"); #include "canohost.h" #include "key.h" #include "authfd.h" - +#include "pathnames.h" +#include "bufaux.h" /* -- channel core */ +#define CHAN_RBUF 16*1024 + /* * Pointer to an array containing all allocated channels. The array is * dynamically extended as needed. @@ -68,7 +70,7 @@ static Channel **channels = NULL; * Size of the channel array. All slots of the array must always be * initialized (at least the type field); unused slots set to NULL */ -static int channels_alloc = 0; +static u_int channels_alloc = 0; /* * Maximum file descriptor value used in any of the channels. This is @@ -128,10 +130,6 @@ static u_int x11_fake_data_len; #define NUM_SOCKS 10 -/* Name and directory of socket for authentication agent forwarding. */ -static char *auth_sock_name = NULL; -static char *auth_sock_dir = NULL; - /* AF_UNSPEC or AF_INET or AF_INET6 */ static int IPv4or6 = AF_UNSPEC; @@ -145,13 +143,13 @@ channel_lookup(int id) { Channel *c; - if (id < 0 || id > channels_alloc) { - log("channel_lookup: %d: bad id", id); + if (id < 0 || (u_int)id >= channels_alloc) { + logit("channel_lookup: %d: bad id", id); return NULL; } c = channels[id]; if (c == NULL) { - log("channel_lookup: %d: bad id: channel free", id); + logit("channel_lookup: %d: bad id: channel free", id); return NULL; } return c; @@ -176,12 +174,13 @@ channel_register_fds(Channel *c, int rfd, int wfd, int efd, c->rfd = rfd; c->wfd = wfd; c->sock = (rfd == wfd) ? rfd : -1; + c->ctl_fd = -1; /* XXX: set elsewhere */ c->efd = efd; c->extended_usage = extusage; /* XXX ugly hack: nonblock is only set by the server */ if (nonblock && isatty(c->rfd)) { - debug("channel %d: rfd %d isatty", c->self, c->rfd); + debug2("channel %d: rfd %d isatty", c->self, c->rfd); c->isatty = 1; if (!isatty(c->wfd)) { error("channel %d: wfd %d is not a tty?", @@ -190,6 +189,7 @@ channel_register_fds(Channel *c, int rfd, int wfd, int efd, } else { c->isatty = 0; } + c->wfd_isatty = isatty(c->wfd); /* enable nonblocking mode */ if (nonblock) { @@ -209,33 +209,36 @@ channel_register_fds(Channel *c, int rfd, int wfd, int efd, Channel * channel_new(char *ctype, int type, int rfd, int wfd, int efd, - int window, int maxpack, int extusage, char *remote_name, int nonblock) + u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock) { - int i, found; + int found; + u_int i; Channel *c; /* Do initial allocation if this is the first call. */ if (channels_alloc == 0) { - chan_init(); channels_alloc = 10; channels = xmalloc(channels_alloc * sizeof(Channel *)); for (i = 0; i < channels_alloc; i++) channels[i] = NULL; - fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL); } /* Try to find a free slot where to put the new channel. */ for (found = -1, i = 0; i < channels_alloc; i++) if (channels[i] == NULL) { /* Found a free slot. */ - found = i; + found = (int)i; break; } - if (found == -1) { + if (found < 0) { /* There are no free slots. Take last+1 slot and expand the array. */ found = channels_alloc; + if (channels_alloc > 10000) + fatal("channel_new: internal error: channels_alloc %d " + "too big.", channels_alloc); + channels = xrealloc(channels, + (channels_alloc + 10) * sizeof(Channel *)); channels_alloc += 10; debug2("channel: expanding %d", channels_alloc); - channels = xrealloc(channels, channels_alloc * sizeof(Channel *)); for (i = found; i < channels_alloc; i++) channels[i] = NULL; } @@ -245,7 +248,9 @@ channel_new(char *ctype, int type, int rfd, int wfd, int efd, buffer_init(&c->input); buffer_init(&c->output); buffer_init(&c->extended); - chan_init_iostates(c); + c->ostate = CHAN_OUTPUT_OPEN; + c->istate = CHAN_INPUT_OPEN; + c->flags = 0; channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); c->self = found; c->type = type; @@ -255,14 +260,14 @@ channel_new(char *ctype, int type, int rfd, int wfd, int efd, c->local_consumed = 0; c->local_maxpacket = maxpack; c->remote_id = -1; - c->remote_name = remote_name; + c->remote_name = xstrdup(remote_name); c->remote_window = 0; c->remote_maxpacket = 0; - c->cb_fn = NULL; - c->cb_arg = NULL; - c->cb_event = 0; c->force_drain = 0; + c->single_connection = 0; c->detach_user = NULL; + c->confirm = NULL; + c->confirm_ctx = NULL; c->input_filter = NULL; debug("channel %d: new [%s]", found, remote_name); return c; @@ -271,7 +276,8 @@ channel_new(char *ctype, int type, int rfd, int wfd, int efd, static int channel_find_maxfd(void) { - int i, max = 0; + u_int i; + int max = 0; Channel *c; for (i = 0; i < channels_alloc; i++) { @@ -304,10 +310,11 @@ channel_close_fd(int *fdp) static void channel_close_fds(Channel *c) { - debug3("channel_close_fds: channel %d: r %d w %d e %d", - c->self, c->rfd, c->wfd, c->efd); + debug3("channel %d: close_fds r %d w %d e %d c %d", + c->self, c->rfd, c->wfd, c->efd, c->ctl_fd); channel_close_fd(&c->sock); + channel_close_fd(&c->ctl_fd); channel_close_fd(&c->rfd); channel_close_fd(&c->wfd); channel_close_fd(&c->efd); @@ -319,20 +326,22 @@ void channel_free(Channel *c) { char *s; - int i, n; + u_int i, n; for (n = 0, i = 0; i < channels_alloc; i++) if (channels[i]) n++; - debug("channel_free: channel %d: %s, nchannels %d", c->self, + debug("channel %d: free: %s, nchannels %u", c->self, c->remote_name ? c->remote_name : "???", n); s = channel_open_message(); - debug3("channel_free: status: %s", s); + debug3("channel %d: status: %s", c->self, s); xfree(s); if (c->sock != -1) shutdown(c->sock, SHUT_RDWR); + if (c->ctl_fd != -1) + shutdown(c->ctl_fd, SHUT_RDWR); channel_close_fds(c); buffer_free(&c->input); buffer_free(&c->output); @@ -348,7 +357,7 @@ channel_free(Channel *c) void channel_free_all(void) { - int i; + u_int i; for (i = 0; i < channels_alloc; i++) if (channels[i] != NULL) @@ -363,7 +372,7 @@ channel_free_all(void) void channel_close_all(void) { - int i; + u_int i; for (i = 0; i < channels_alloc; i++) if (channels[i] != NULL) @@ -377,7 +386,7 @@ channel_close_all(void) void channel_stop_listening(void) { - int i; + u_int i; Channel *c; for (i = 0; i < channels_alloc; i++) { @@ -413,13 +422,13 @@ channel_not_very_much_buffered_data(void) #if 0 if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) { - debug("channel %d: big input buffer %d", + debug2("channel %d: big input buffer %d", c->self, buffer_len(&c->input)); return 0; } #endif if (buffer_len(&c->output) > packet_get_maxsize()) { - debug("channel %d: big output buffer %d > %d", + debug2("channel %d: big output buffer %u > %u", c->self, buffer_len(&c->output), packet_get_maxsize()); return 0; @@ -434,7 +443,7 @@ channel_not_very_much_buffered_data(void) int channel_still_open(void) { - int i; + u_int i; Channel *c; for (i = 0; i < channels_alloc; i++) { @@ -477,12 +486,12 @@ channel_still_open(void) int channel_find_open(void) { - int i; + u_int i; Channel *c; for (i = 0; i < channels_alloc; i++) { c = channels[i]; - if (c == NULL) + if (c == NULL || c->remote_id < 0) continue; switch (c->type) { case SSH_CHANNEL_CLOSED: @@ -525,7 +534,7 @@ channel_open_message(void) Buffer buffer; Channel *c; char buf[1024], *cp; - int i; + u_int i; buffer_init(&buffer); snprintf(buf, sizeof buf, "The following connections are open:\r\n"); @@ -550,12 +559,13 @@ channel_open_message(void) case SSH_CHANNEL_X11_OPEN: case SSH_CHANNEL_INPUT_DRAINING: case SSH_CHANNEL_OUTPUT_DRAINING: - snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", + snprintf(buf, sizeof buf, + " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n", c->self, c->remote_name, c->type, c->remote_id, c->istate, buffer_len(&c->input), c->ostate, buffer_len(&c->output), - c->rfd, c->wfd); + c->rfd, c->wfd, c->ctl_fd); buffer_append(&buffer, buf, strlen(buf)); continue; default: @@ -573,11 +583,12 @@ void channel_send_open(int id) { Channel *c = channel_lookup(id); + if (c == NULL) { - log("channel_send_open: %d: bad id", id); + logit("channel_send_open: %d: bad id", id); return; } - debug("send channel open %d", id); + debug2("channel %d: send open", id); packet_start(SSH2_MSG_CHANNEL_OPEN); packet_put_cstring(c->ctype); packet_put_int(c->self); @@ -586,44 +597,40 @@ channel_send_open(int id) packet_send(); } -void -channel_request(int id, char *service, int wantconfirm) -{ - channel_request_start(id, service, wantconfirm); - packet_send(); - debug("channel request %d: %s", id, service) ; -} void channel_request_start(int id, char *service, int wantconfirm) { Channel *c = channel_lookup(id); + if (c == NULL) { - log("channel_request: %d: bad id", id); + logit("channel_request_start: %d: unknown channel id", id); return; } + debug2("channel %d: request %s confirm %d", id, service, wantconfirm); packet_start(SSH2_MSG_CHANNEL_REQUEST); packet_put_int(c->remote_id); packet_put_cstring(service); packet_put_char(wantconfirm); } void -channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) +channel_register_confirm(int id, channel_callback_fn *fn, void *ctx) { Channel *c = channel_lookup(id); + if (c == NULL) { - log("channel_register_callback: %d: bad id", id); + logit("channel_register_comfirm: %d: bad id", id); return; } - c->cb_event = mtype; - c->cb_fn = fn; - c->cb_arg = arg; + c->confirm = fn; + c->confirm_ctx = ctx; } void channel_register_cleanup(int id, channel_callback_fn *fn) { Channel *c = channel_lookup(id); + if (c == NULL) { - log("channel_register_cleanup: %d: bad id", id); + logit("channel_register_cleanup: %d: bad id", id); return; } c->detach_user = fn; @@ -632,8 +639,9 @@ void channel_cancel_cleanup(int id) { Channel *c = channel_lookup(id); + if (c == NULL) { - log("channel_cancel_cleanup: %d: bad id", id); + logit("channel_cancel_cleanup: %d: bad id", id); return; } c->detach_user = NULL; @@ -642,8 +650,9 @@ void channel_register_filter(int id, channel_filter_fn *fn) { Channel *c = channel_lookup(id); + if (c == NULL) { - log("channel_register_filter: %d: bad id", id); + logit("channel_register_filter: %d: bad id", id); return; } c->input_filter = fn; @@ -651,15 +660,15 @@ channel_register_filter(int id, channel_filter_fn *fn) void channel_set_fds(int id, int rfd, int wfd, int efd, - int extusage, int nonblock) + int extusage, int nonblock, u_int window_max) { Channel *c = channel_lookup(id); + if (c == NULL || c->type != SSH_CHANNEL_LARVAL) fatal("channel_activate for non-larval channel %d.", id); channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); c->type = SSH_CHANNEL_OPEN; - /* XXX window size? */ - c->local_window = c->local_window_max = c->local_maxpacket * 2; + c->local_window = c->local_window_max = window_max; packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); packet_put_int(c->remote_id); packet_put_int(c->local_window); @@ -701,46 +710,43 @@ channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) } static void -channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset) +channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset) { - /* test whether sockets are 'alive' for read/write */ - if (c->istate == CHAN_INPUT_OPEN) - if (buffer_len(&c->input) < packet_get_maxsize()) - FD_SET(c->sock, readset); - if (c->ostate == CHAN_OUTPUT_OPEN || - c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { - if (buffer_len(&c->output) > 0) { - FD_SET(c->sock, writeset); - } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { - chan_obuf_empty(c); - } - } -} + u_int limit = compat20 ? c->remote_window : packet_get_maxsize(); + + /* check buffer limits */ + limit = MIN(limit, (BUFFER_MAX_LEN - BUFFER_MAX_CHUNK - CHAN_RBUF)); -static void -channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset) -{ if (c->istate == CHAN_INPUT_OPEN && - c->remote_window > 0 && - buffer_len(&c->input) < c->remote_window) + limit > 0 && + buffer_len(&c->input) < limit) FD_SET(c->rfd, readset); if (c->ostate == CHAN_OUTPUT_OPEN || c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { if (buffer_len(&c->output) > 0) { FD_SET(c->wfd, writeset); } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { - chan_obuf_empty(c); + if (CHANNEL_EFD_OUTPUT_ACTIVE(c)) + debug2("channel %d: obuf_empty delayed efd %d/(%d)", + c->self, c->efd, buffer_len(&c->extended)); + else + chan_obuf_empty(c); } } /** XXX check close conditions, too */ - if (c->efd != -1) { + if (compat20 && c->efd != -1) { if (c->extended_usage == CHAN_EXTENDED_WRITE && buffer_len(&c->extended) > 0) FD_SET(c->efd, writeset); - else if (c->extended_usage == CHAN_EXTENDED_READ && + else if (!(c->flags & CHAN_EOF_SENT) && + c->extended_usage == CHAN_EXTENDED_READ && buffer_len(&c->extended) < c->remote_window) FD_SET(c->efd, readset); } + /* XXX: What about efd? races? */ + if (compat20 && c->ctl_fd != -1 && + c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN) + FD_SET(c->ctl_fd, readset); } static void @@ -751,7 +757,7 @@ channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) packet_put_int(c->remote_id); packet_send(); c->type = SSH_CHANNEL_CLOSED; - debug("channel %d: closing after input drain.", c->self); + debug2("channel %d: closing after input drain.", c->self); } } @@ -784,7 +790,7 @@ x11_open_helper(Buffer *b) return 0; /* Parse the lengths of variable-length fields. */ - ucp = (u_char *) buffer_ptr(b); + ucp = buffer_ptr(b); if (ucp[0] == 0x42) { /* Byte order MSB first. */ proto_len = 256 * ucp[6] + ucp[7]; data_len = 256 * ucp[8] + ucp[9]; @@ -792,8 +798,8 @@ x11_open_helper(Buffer *b) proto_len = ucp[6] + 256 * ucp[7]; data_len = ucp[8] + 256 * ucp[9]; } else { - debug("Initial X11 packet contains bad byte order byte: 0x%x", - ucp[0]); + debug2("Initial X11 packet contains bad byte order byte: 0x%x", + ucp[0]); return -1; } @@ -805,14 +811,14 @@ x11_open_helper(Buffer *b) /* Check if authentication protocol matches. */ if (proto_len != strlen(x11_saved_proto) || memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { - debug("X11 connection uses different authentication protocol."); + debug2("X11 connection uses different authentication protocol."); return -1; } /* Check if authentication data matches our fake data. */ if (data_len != x11_fake_data_len || memcmp(ucp + 12 + ((proto_len + 3) & ~3), x11_fake_data, x11_fake_data_len) != 0) { - debug("X11 auth data does not match fake data."); + debug2("X11 auth data does not match fake data."); return -1; } /* Check fake data length */ @@ -835,6 +841,7 @@ static void channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) { int ret = x11_open_helper(&c->output); + if (ret == 1) { /* Start normal processing for the channel. */ c->type = SSH_CHANNEL_OPEN; @@ -844,7 +851,7 @@ channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) * We have received an X11 connection that has bad * authentication information. */ - log("X11 connection rejected because of wrong authentication."); + logit("X11 connection rejected because of wrong authentication."); buffer_clear(&c->input); buffer_clear(&c->output); channel_close_fd(&c->sock); @@ -865,15 +872,20 @@ channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) if (ret == 1) { c->type = SSH_CHANNEL_OPEN; + channel_pre_open(c, readset, writeset); + } else if (ret == -1) { + logit("X11 connection rejected because of wrong authentication."); + debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); + chan_read_failed(c); + buffer_clear(&c->input); + chan_ibuf_empty(c); + buffer_clear(&c->output); + /* for proto v1, the peer will send an IEOF */ if (compat20) - channel_pre_open_20(c, readset, writeset); + chan_write_failed(c); else - channel_pre_open_15(c, readset, writeset); - } else if (ret == -1) { - debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); - chan_read_failed(c); /** force close? */ - chan_write_failed(c); - debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); + c->type = SSH_CHANNEL_OPEN; + debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); } } @@ -881,9 +893,9 @@ channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) static int channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) { - u_char *p, *host; + char *p, *host; int len, have, i, found; - char username[256]; + char username[256]; struct { u_int8_t version; u_int8_t command; @@ -930,8 +942,8 @@ channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) host = inet_ntoa(s4_req.dest_addr); strlcpy(c->path, host, sizeof(c->path)); c->host_port = ntohs(s4_req.dest_port); - - debug("channel %d: dynamic request: socks4 host %s port %u command %u", + + debug2("channel %d: dynamic request: socks4 host %s port %u command %u", c->self, host, c->host_port, s4_req.command); if (s4_req.command != 1) { @@ -947,6 +959,117 @@ channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) return 1; } +/* try to decode a socks5 header */ +#define SSH_SOCKS5_AUTHDONE 0x1000 +#define SSH_SOCKS5_NOAUTH 0x00 +#define SSH_SOCKS5_IPV4 0x01 +#define SSH_SOCKS5_DOMAIN 0x03 +#define SSH_SOCKS5_IPV6 0x04 +#define SSH_SOCKS5_CONNECT 0x01 +#define SSH_SOCKS5_SUCCESS 0x00 + +static int +channel_decode_socks5(Channel *c, fd_set * readset, fd_set * writeset) +{ + struct { + u_int8_t version; + u_int8_t command; + u_int8_t reserved; + u_int8_t atyp; + } s5_req, s5_rsp; + u_int16_t dest_port; + u_char *p, dest_addr[255+1]; + int i, have, found, nmethods, addrlen, af; + + debug2("channel %d: decode socks5", c->self); + p = buffer_ptr(&c->input); + if (p[0] != 0x05) + return -1; + have = buffer_len(&c->input); + if (!(c->flags & SSH_SOCKS5_AUTHDONE)) { + /* format: ver | nmethods | methods */ + if (have < 2) + return 0; + nmethods = p[1]; + if (have < nmethods + 2) + return 0; + /* look for method: "NO AUTHENTICATION REQUIRED" */ + for (found = 0, i = 2 ; i < nmethods + 2; i++) { + if (p[i] == SSH_SOCKS5_NOAUTH ) { + found = 1; + break; + } + } + if (!found) { + debug("channel %d: method SSH_SOCKS5_NOAUTH not found", + c->self); + return -1; + } + buffer_consume(&c->input, nmethods + 2); + buffer_put_char(&c->output, 0x05); /* version */ + buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */ + FD_SET(c->sock, writeset); + c->flags |= SSH_SOCKS5_AUTHDONE; + debug2("channel %d: socks5 auth done", c->self); + return 0; /* need more */ + } + debug2("channel %d: socks5 post auth", c->self); + if (have < sizeof(s5_req)+1) + return 0; /* need more */ + memcpy((char *)&s5_req, p, sizeof(s5_req)); + if (s5_req.version != 0x05 || + s5_req.command != SSH_SOCKS5_CONNECT || + s5_req.reserved != 0x00) { + debug2("channel %d: only socks5 connect supported", c->self); + return -1; + } + switch (s5_req.atyp){ + case SSH_SOCKS5_IPV4: + addrlen = 4; + af = AF_INET; + break; + case SSH_SOCKS5_DOMAIN: + addrlen = p[sizeof(s5_req)]; + af = -1; + break; + case SSH_SOCKS5_IPV6: + addrlen = 16; + af = AF_INET6; + break; + default: + debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp); + return -1; + } + if (have < 4 + addrlen + 2) + return 0; + buffer_consume(&c->input, sizeof(s5_req)); + if (s5_req.atyp == SSH_SOCKS5_DOMAIN) + buffer_consume(&c->input, 1); /* host string length */ + buffer_get(&c->input, (char *)&dest_addr, addrlen); + buffer_get(&c->input, (char *)&dest_port, 2); + dest_addr[addrlen] = '\0'; + if (s5_req.atyp == SSH_SOCKS5_DOMAIN) + strlcpy(c->path, (char *)dest_addr, sizeof(c->path)); + else if (inet_ntop(af, dest_addr, c->path, sizeof(c->path)) == NULL) + return -1; + c->host_port = ntohs(dest_port); + + debug2("channel %d: dynamic request: socks5 host %s port %u command %u", + c->self, c->path, c->host_port, s5_req.command); + + s5_rsp.version = 0x05; + s5_rsp.command = SSH_SOCKS5_SUCCESS; + s5_rsp.reserved = 0; /* ignored */ + s5_rsp.atyp = SSH_SOCKS5_IPV4; + ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY; + dest_port = 0; /* ignored */ + + buffer_append(&c->output, (char *)&s5_rsp, sizeof(s5_rsp)); + buffer_append(&c->output, (char *)&dest_addr, sizeof(struct in_addr)); + buffer_append(&c->output, (char *)&dest_port, sizeof(dest_port)); + return 1; +} + /* dynamic port forwarding */ static void channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) @@ -959,7 +1082,7 @@ channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) debug2("channel %d: pre_dynamic: have %d", c->self, have); /* buffer_dump(&c->input); */ /* check if the fixed size part of the packet is in buffer. */ - if (have < 4) { + if (have < 3) { /* need more */ FD_SET(c->sock, readset); return; @@ -970,6 +1093,9 @@ channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) case 0x04: ret = channel_decode_socks4(c, readset, writeset); break; + case 0x05: + ret = channel_decode_socks5(c, readset, writeset); + break; default: ret = -1; break; @@ -1002,10 +1128,16 @@ channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) debug("X11 connection requested."); addrlen = sizeof(addr); newsock = accept(c->sock, &addr, &addrlen); + if (c->single_connection) { + debug2("single_connection: closing X11 listener."); + channel_close_fd(&c->sock); + chan_mark_dead(c); + } if (newsock < 0) { error("accept: %.100s", strerror(errno)); return; } + set_nodelay(newsock); remote_ipaddr = get_peer_ipaddr(newsock); remote_port = get_peer_port(newsock); snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", @@ -1013,23 +1145,17 @@ channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) nc = channel_new("accepted x11 socket", SSH_CHANNEL_OPENING, newsock, newsock, -1, - c->local_window_max, c->local_maxpacket, - 0, xstrdup(buf), 1); - if (nc == NULL) { - close(newsock); - xfree(remote_ipaddr); - return; - } + c->local_window_max, c->local_maxpacket, 0, buf, 1); if (compat20) { packet_start(SSH2_MSG_CHANNEL_OPEN); packet_put_cstring("x11"); packet_put_int(nc->self); - packet_put_int(c->local_window_max); - packet_put_int(c->local_maxpacket); + packet_put_int(nc->local_window_max); + packet_put_int(nc->local_maxpacket); /* originator ipaddr and port */ packet_put_cstring(remote_ipaddr); if (datafellows & SSH_BUG_X11FWD) { - debug("ssh2 x11 bug compat mode"); + debug2("ssh2 x11 bug compat mode"); } else { packet_put_int(remote_port); } @@ -1133,15 +1259,9 @@ channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) error("accept: %.100s", strerror(errno)); return; } - nc = channel_new(rtype, - nextstate, newsock, newsock, -1, - c->local_window_max, c->local_maxpacket, - 0, xstrdup(rtype), 1); - if (nc == NULL) { - error("channel_post_port_listener: no new channel:"); - close(newsock); - return; - } + set_nodelay(newsock); + nc = channel_new(rtype, nextstate, newsock, newsock, -1, + c->local_window_max, c->local_maxpacket, 0, rtype, 1); nc->listening_port = c->listening_port; nc->host_port = c->host_port; strlcpy(nc->path, c->path, sizeof(nc->path)); @@ -1167,7 +1287,6 @@ static void channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) { Channel *nc; - char *name; int newsock; struct sockaddr addr; socklen_t addrlen; @@ -1179,16 +1298,10 @@ channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) error("accept from auth socket: %.100s", strerror(errno)); return; } - name = xstrdup("accepted auth socket"); nc = channel_new("accepted auth socket", SSH_CHANNEL_OPENING, newsock, newsock, -1, c->local_window_max, c->local_maxpacket, - 0, name, 1); - if (nc == NULL) { - error("channel_post_auth_listener: channel_new failed"); - xfree(name); - close(newsock); - } + 0, "accepted auth socket", 1); if (compat20) { packet_start(SSH2_MSG_CHANNEL_OPEN); packet_put_cstring("auth-agent@openssh.com"); @@ -1210,8 +1323,7 @@ channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset) socklen_t sz = sizeof(err); if (FD_ISSET(c->sock, writeset)) { - if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err, - &sz) < 0) { + if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) { err = errno; error("getsockopt SO_ERROR failed"); } @@ -1253,7 +1365,7 @@ 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 && @@ -1262,24 +1374,24 @@ channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) if (len < 0 && (errno == EINTR || errno == EAGAIN)) return 1; if (len <= 0) { - debug("channel %d: read<=0 rfd %d len %d", + debug2("channel %d: read<=0 rfd %d len %d", c->self, c->rfd, len); if (c->type != SSH_CHANNEL_OPEN) { - debug("channel %d: not open", c->self); + debug2("channel %d: not open", c->self); chan_mark_dead(c); return -1; } else if (compat13) { - buffer_consume(&c->output, buffer_len(&c->output)); + buffer_clear(&c->output); c->type = SSH_CHANNEL_INPUT_DRAINING; - debug("channel %d: input draining.", c->self); + debug2("channel %d: input draining.", c->self); } else { chan_read_failed(c); } return -1; } - if(c->input_filter != NULL) { + if (c->input_filter != NULL) { if (c->input_filter(c, buf, len) == -1) { - debug("channel %d: filter stops", c->self); + debug2("channel %d: filter stops", c->self); chan_read_failed(c); } } else { @@ -1302,17 +1414,22 @@ channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) buffer_len(&c->output) > 0) { data = buffer_ptr(&c->output); dlen = buffer_len(&c->output); +#ifdef _AIX + /* XXX: Later AIX versions can't push as much data to tty */ + if (compat20 && c->wfd_isatty) + dlen = MIN(dlen, 8*1024); +#endif len = write(c->wfd, data, dlen); if (len < 0 && (errno == EINTR || errno == EAGAIN)) return 1; if (len <= 0) { if (c->type != SSH_CHANNEL_OPEN) { - debug("channel %d: not open", c->self); + debug2("channel %d: not open", c->self); chan_mark_dead(c); return -1; } else if (compat13) { - buffer_consume(&c->output, buffer_len(&c->output)); - debug("channel %d: input draining.", c->self); + buffer_clear(&c->output); + debug2("channel %d: input draining.", c->self); c->type = SSH_CHANNEL_INPUT_DRAINING; } else { chan_write_failed(c); @@ -1342,7 +1459,7 @@ 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 */ @@ -1368,7 +1485,7 @@ channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) FD_ISSET(c->efd, readset)) { len = read(c->efd, buf, sizeof(buf)); debug2("channel %d: read %d from efd %d", - c->self, len, c->efd); + c->self, len, c->efd); if (len < 0 && (errno == EINTR || errno == EAGAIN)) return 1; if (len <= 0) { @@ -1383,6 +1500,33 @@ channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) return 1; } static int +channel_handle_ctl(Channel *c, fd_set * readset, fd_set * writeset) +{ + char buf[16]; + int len; + + /* Monitor control fd to detect if the slave client exits */ + if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) { + len = read(c->ctl_fd, buf, sizeof(buf)); + if (len < 0 && (errno == EINTR || errno == EAGAIN)) + return 1; + if (len <= 0) { + debug2("channel %d: ctl read<=0", c->self); + if (c->type != SSH_CHANNEL_OPEN) { + debug2("channel %d: not open", c->self); + chan_mark_dead(c); + return -1; + } else { + chan_read_failed(c); + chan_write_failed(c); + } + return -1; + } else + fatal("%s: unexpected data on ctl fd", __func__); + } + return 1; +} +static int channel_check_window(Channel *c) { if (c->type == SSH_CHANNEL_OPEN && @@ -1403,23 +1547,16 @@ channel_check_window(Channel *c) } static void -channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset) +channel_post_open(Channel *c, fd_set * readset, fd_set * writeset) { if (c->delayed) return; channel_handle_rfd(c, readset, writeset); channel_handle_wfd(c, readset, writeset); -} - -static void -channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset) -{ - if (c->delayed) + if (!compat20) return; - channel_handle_rfd(c, readset, writeset); - channel_handle_wfd(c, readset, writeset); channel_handle_efd(c, readset, writeset); - + channel_handle_ctl(c, readset, writeset); channel_check_window(c); } @@ -1427,12 +1564,13 @@ static void channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) { int len; + /* Send buffered output data to the socket. */ if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { len = write(c->sock, buffer_ptr(&c->output), buffer_len(&c->output)); if (len <= 0) - buffer_consume(&c->output, buffer_len(&c->output)); + buffer_clear(&c->output); else buffer_consume(&c->output, len); } @@ -1441,7 +1579,7 @@ channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) static void channel_handler_init_20(void) { - channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20; + channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; @@ -1450,13 +1588,13 @@ channel_handler_init_20(void) channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; - channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2; + channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; - channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2; + channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; } static void @@ -1472,19 +1610,19 @@ channel_handler_init_13(void) channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; - channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; + channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; - channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; + channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; } static void channel_handler_init_15(void) { - channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15; + channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; @@ -1495,16 +1633,17 @@ channel_handler_init_15(void) channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; - channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; + channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; - channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; + channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; } static void channel_handler_init(void) { int i; - for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { + + for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { channel_pre[i] = NULL; channel_post[i] = NULL; } @@ -1525,16 +1664,16 @@ channel_garbage_collect(Channel *c) if (c->detach_user != NULL) { if (!chan_is_dead(c, 0)) return; - debug("channel %d: gc: notify user", c->self); + debug2("channel %d: gc: notify user", c->self); c->detach_user(c->self, NULL); /* if we still have a callback */ if (c->detach_user != NULL) return; - debug("channel %d: gc: user detached", c->self); + debug2("channel %d: gc: user detached", c->self); } if (!chan_is_dead(c, 1)) return; - debug("channel %d: garbage collecting", c->self); + debug2("channel %d: garbage collecting", c->self); channel_free(c); } @@ -1542,7 +1681,7 @@ static void channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) { static int did_init = 0; - int i; + u_int i; Channel *c; if (!did_init) { @@ -1565,10 +1704,9 @@ channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) */ void channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, - int *nallocp, int rekeying) + u_int *nallocp, int rekeying) { - int n; - u_int sz; + u_int n, sz; n = MAX(*maxfdp, channel_max_fd); @@ -1603,8 +1741,8 @@ channel_after_select(fd_set * readset, fd_set * writeset) void channel_output_poll(void) { - int len, i; Channel *c; + u_int i, len; for (i = 0; i < channels_alloc; i++) { c = channels[i]; @@ -1667,16 +1805,22 @@ channel_output_poll(void) fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); /* * input-buffer is empty and read-socket shutdown: - * tell peer, that we will not send more data: send IEOF + * tell peer, that we will not send more data: send IEOF. + * hack for extended data: delay EOF if EFD still in use. */ - chan_ibuf_empty(c); + if (CHANNEL_EFD_INPUT_ACTIVE(c)) + debug2("channel %d: ibuf_empty delayed efd %d/(%d)", + c->self, c->efd, buffer_len(&c->extended)); + else + chan_ibuf_empty(c); } /* Send extended data, i.e. stderr */ if (compat20 && + !(c->flags & CHAN_EOF_SENT) && c->remote_window > 0 && (len = buffer_len(&c->extended)) > 0 && c->extended_usage == CHAN_EXTENDED_READ) { - debug2("channel %d: rwin %d elen %d euse %d", + debug2("channel %d: rwin %u elen %u euse %d", c->self, c->remote_window, buffer_len(&c->extended), c->extended_usage); if (len > c->remote_window) @@ -1699,7 +1843,7 @@ channel_output_poll(void) /* -- protocol input */ void -channel_input_data(int type, int plen, void *ctxt) +channel_input_data(int type, u_int32_t seq, void *ctxt) { int id; char *data; @@ -1717,40 +1861,49 @@ channel_input_data(int type, int plen, void *ctxt) c->type != SSH_CHANNEL_X11_OPEN) return; - /* same for protocol 1.5 if output end is no longer open */ - if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) - return; - /* Get the data. */ data = packet_get_string(&data_len); - packet_done(); - if (compat20){ + /* + * Ignore data for protocol > 1.3 if output end is no longer open. + * For protocol 2 the sending side is reducing its window as it sends + * data, so we must 'fake' consumption of the data in order to ensure + * that window updates are sent back. Otherwise the connection might + * deadlock. + */ + if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) { + if (compat20) { + c->local_window -= data_len; + c->local_consumed += data_len; + } + xfree(data); + return; + } + + if (compat20) { if (data_len > c->local_maxpacket) { - log("channel %d: rcvd big packet %d, maxpack %d", + logit("channel %d: rcvd big packet %d, maxpack %d", c->self, data_len, c->local_maxpacket); } if (data_len > c->local_window) { - log("channel %d: rcvd too much data %d, win %d", + logit("channel %d: rcvd too much data %d, win %d", c->self, data_len, c->local_window); xfree(data); return; } c->local_window -= data_len; - }else{ - packet_integrity_check(plen, 4 + 4 + data_len, type); } + packet_check_eom(); buffer_append(&c->output, data, data_len); xfree(data); } void -channel_input_extended_data(int type, int plen, void *ctxt) +channel_input_extended_data(int type, u_int32_t seq, void *ctxt) { int id; - int tcode; char *data; - u_int data_len; + u_int data_len, tcode; Channel *c; /* Get the channel number and verify it. */ @@ -1760,20 +1913,27 @@ channel_input_extended_data(int type, int plen, void *ctxt) if (c == NULL) packet_disconnect("Received extended_data for bad channel %d.", id); if (c->type != SSH_CHANNEL_OPEN) { - log("channel %d: ext data for non open", id); + logit("channel %d: ext data for non open", id); return; } + if (c->flags & CHAN_EOF_RCVD) { + if (datafellows & SSH_BUG_EXTEOF) + debug("channel %d: accepting ext data after eof", id); + else + packet_disconnect("Received extended_data after EOF " + "on channel %d.", id); + } tcode = packet_get_int(); if (c->efd == -1 || c->extended_usage != CHAN_EXTENDED_WRITE || tcode != SSH2_EXTENDED_DATA_STDERR) { - log("channel %d: bad ext data", c->self); + logit("channel %d: bad ext data", c->self); return; } data = packet_get_string(&data_len); - packet_done(); + packet_check_eom(); if (data_len > c->local_window) { - log("channel %d: rcvd too much extended_data %d, win %d", + logit("channel %d: rcvd too much extended_data %d, win %d", c->self, data_len, c->local_window); xfree(data); return; @@ -1785,36 +1945,36 @@ channel_input_extended_data(int type, int plen, void *ctxt) } void -channel_input_ieof(int type, int plen, void *ctxt) +channel_input_ieof(int type, u_int32_t seq, void *ctxt) { int id; Channel *c; - packet_integrity_check(plen, 4, type); - id = packet_get_int(); + packet_check_eom(); c = channel_lookup(id); if (c == NULL) packet_disconnect("Received ieof for nonexistent channel %d.", id); chan_rcvd_ieof(c); /* XXX force input close */ - if (c->force_drain) { + if (c->force_drain && c->istate == CHAN_INPUT_OPEN) { debug("channel %d: FORCE input drain", c->self); c->istate = CHAN_INPUT_WAIT_DRAIN; + if (buffer_len(&c->input) == 0) + chan_ibuf_empty(c); } } void -channel_input_close(int type, int plen, void *ctxt) +channel_input_close(int type, u_int32_t seq, void *ctxt) { int id; Channel *c; - packet_integrity_check(plen, 4, type); - id = packet_get_int(); + packet_check_eom(); c = channel_lookup(id); if (c == NULL) packet_disconnect("Received close for nonexistent channel %d.", id); @@ -1839,30 +1999,31 @@ channel_input_close(int type, int plen, void *ctxt) * Not a closed channel - mark it as draining, which will * cause it to be freed later. */ - buffer_consume(&c->input, buffer_len(&c->input)); + buffer_clear(&c->input); c->type = SSH_CHANNEL_OUTPUT_DRAINING; } } /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ void -channel_input_oclose(int type, int plen, void *ctxt) +channel_input_oclose(int type, u_int32_t seq, void *ctxt) { int id = packet_get_int(); Channel *c = channel_lookup(id); - packet_integrity_check(plen, 4, type); + + packet_check_eom(); if (c == NULL) packet_disconnect("Received oclose for nonexistent channel %d.", id); chan_rcvd_oclose(c); } void -channel_input_close_confirmation(int type, int plen, void *ctxt) +channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt) { int id = packet_get_int(); Channel *c = channel_lookup(id); - packet_done(); + packet_check_eom(); if (c == NULL) packet_disconnect("Received close confirmation for " "out-of-range channel %d.", id); @@ -1873,14 +2034,11 @@ channel_input_close_confirmation(int type, int plen, void *ctxt) } void -channel_input_open_confirmation(int type, int plen, void *ctxt) +channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt) { int id, remote_id; Channel *c; - if (!compat20) - packet_integrity_check(plen, 4 + 4, type); - id = packet_get_int(); c = channel_lookup(id); @@ -1895,21 +2053,21 @@ channel_input_open_confirmation(int type, int plen, void *ctxt) if (compat20) { c->remote_window = packet_get_int(); c->remote_maxpacket = packet_get_int(); - packet_done(); - if (c->cb_fn != NULL && c->cb_event == type) { + if (c->confirm) { debug2("callback start"); - c->cb_fn(c->self, c->cb_arg); + c->confirm(c->self, c->confirm_ctx); debug2("callback done"); } - debug("channel %d: open confirm rwindow %d rmax %d", c->self, + debug2("channel %d: open confirm rwindow %u rmax %u", c->self, c->remote_window, c->remote_maxpacket); } + packet_check_eom(); } static char * reason2txt(int reason) { - switch(reason) { + switch (reason) { case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED: return "administratively prohibited"; case SSH2_OPEN_CONNECT_FAILED: @@ -1923,15 +2081,12 @@ reason2txt(int reason) } void -channel_input_open_failure(int type, int plen, void *ctxt) +channel_input_open_failure(int type, u_int32_t seq, void *ctxt) { int id, reason; char *msg = NULL, *lang = NULL; Channel *c; - if (!compat20) - packet_integrity_check(plen, 4, type); - id = packet_get_int(); c = channel_lookup(id); @@ -1944,48 +2099,24 @@ channel_input_open_failure(int type, int plen, void *ctxt) msg = packet_get_string(NULL); lang = packet_get_string(NULL); } - packet_done(); - log("channel %d: open failed: %s%s%s", id, + logit("channel %d: open failed: %s%s%s", id, reason2txt(reason), msg ? ": ": "", msg ? msg : ""); if (msg != NULL) xfree(msg); if (lang != NULL) xfree(lang); } + packet_check_eom(); /* Free the channel. This will also close the socket. */ channel_free(c); } void -channel_input_channel_request(int type, int plen, void *ctxt) +channel_input_window_adjust(int type, u_int32_t seq, void *ctxt) { - int id; Channel *c; - - id = packet_get_int(); - c = channel_lookup(id); - - if (c == NULL || - (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL)) - packet_disconnect("Received request for " - "non-open channel %d.", id); - if (c->cb_fn != NULL && c->cb_event == type) { - debug2("callback start"); - c->cb_fn(c->self, c->cb_arg); - debug2("callback done"); - } else { - char *service = packet_get_string(NULL); - debug("channel %d: rcvd request for %s", c->self, service); - debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event); - xfree(service); - } -} - -void -channel_input_window_adjust(int type, int plen, void *ctxt) -{ - Channel *c; - int id, adjust; + int id; + u_int adjust; if (!compat20) return; @@ -1995,18 +2126,18 @@ channel_input_window_adjust(int type, int plen, void *ctxt) c = channel_lookup(id); if (c == NULL || c->type != SSH_CHANNEL_OPEN) { - log("Received window adjust for " + logit("Received window adjust for " "non-open channel %d.", id); return; } adjust = packet_get_int(); - packet_done(); - debug2("channel %d: rcvd adjust %d", id, adjust); + packet_check_eom(); + debug2("channel %d: rcvd adjust %u", id, adjust); c->remote_window += adjust; } void -channel_input_port_open(int type, int plen, void *ctxt) +channel_input_port_open(int type, u_int32_t seq, void *ctxt) { Channel *c = NULL; u_short host_port; @@ -2022,19 +2153,15 @@ channel_input_port_open(int type, int plen, void *ctxt) } else { originator_string = xstrdup("unknown (remote did not supply name)"); } - packet_done(); + packet_check_eom(); sock = channel_connect_to(host, host_port); if (sock != -1) { c = channel_new("connected socket", SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, originator_string, 1); - if (c == NULL) { - error("channel_input_port_open: channel_new failed"); - close(sock); - } else { - c->remote_id = remote_id; - } + c->remote_id = remote_id; } + xfree(originator_string); if (c == NULL) { packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); packet_put_int(remote_id); @@ -2052,88 +2179,108 @@ channel_set_af(int af) IPv4or6 = af; } -/* - * Initiate forwarding of connections to local port "port" through the secure - * channel to host:port from remote side. - */ -int -channel_request_local_forwarding(u_short listen_port, const char *host_to_connect, - u_short port_to_connect, int gateway_ports) -{ - return channel_request_forwarding( - NULL, listen_port, - host_to_connect, port_to_connect, - gateway_ports, /*remote_fwd*/ 0); -} - -/* - * If 'remote_fwd' is true we have a '-R style' listener for protocol 2 - * (SSH_CHANNEL_RPORT_LISTENER). - */ -int -channel_request_forwarding( - const char *listen_address, u_short listen_port, - const char *host_to_connect, u_short port_to_connect, - int gateway_ports, int remote_fwd) +static int +channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port, + const char *host_to_connect, u_short port_to_connect, int gateway_ports) { Channel *c; - int success, sock, on = 1, type; + int sock, r, success = 0, on = 1, wildcard = 0, is_client; struct addrinfo hints, *ai, *aitop; + const char *host, *addr; char ntop[NI_MAXHOST], strport[NI_MAXSERV]; - const char *host; - struct linger linger; - success = 0; + host = (type == SSH_CHANNEL_RPORT_LISTENER) ? + listen_addr : host_to_connect; + is_client = (type == SSH_CHANNEL_PORT_LISTENER); - if (remote_fwd) { - host = listen_address; - type = SSH_CHANNEL_RPORT_LISTENER; - } else { - host = host_to_connect; - type = SSH_CHANNEL_PORT_LISTENER; + if (host == NULL) { + error("No forward host name."); + return success; } - if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) { error("Forward host name too long."); return success; } - /* XXX listen_address is currently ignored */ + /* + * 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 { + verbose("channel_setup_fwd_listener: " + "getaddrinfo(%.64s): %s", addr, gai_strerror(r)); + packet_send_debug("channel_setup_fwd_listener: " + "getaddrinfo(%.64s): %s", addr, gai_strerror(r)); + } + aitop = NULL; + } for (ai = aitop; ai; ai = ai->ai_next) { if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) continue; if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { - error("channel_request_forwarding: getnameinfo failed"); + error("channel_setup_fwd_listener: getnameinfo failed"); continue; } /* Create a port to listen for the host. */ - sock = socket(ai->ai_family, SOCK_STREAM, 0); + sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); if (sock < 0) { /* this is no error since kernel may not support ipv6 */ verbose("socket: %.100s", strerror(errno)); continue; } /* - * Set socket options. We would like the socket to disappear - * as soon as it has been closed for whatever reason. + * Set socket options. + * Allow local port reuse in TIME_WAIT. */ - setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); - linger.l_onoff = 1; - linger.l_linger = 5; - setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger)); + if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on, + sizeof(on)) == -1) + error("setsockopt SO_REUSEADDR: %s", strerror(errno)); + debug("Local forwarding listening on %s port %s.", ntop, strport); /* Bind the socket to the address. */ @@ -2148,7 +2295,7 @@ channel_request_forwarding( continue; } /* Start listening for connections on the socket. */ - if (listen(sock, 5) < 0) { + if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { error("listen: %.100s", strerror(errno)); close(sock); continue; @@ -2156,34 +2303,69 @@ channel_request_forwarding( /* Allocate a channel number for the socket. */ c = channel_new("port listener", type, sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, - 0, xstrdup("port listener"), 1); - if (c == NULL) { - error("channel_request_forwarding: channel_new failed"); - close(sock); - continue; - } + 0, "port listener", 1); strlcpy(c->path, host, sizeof(c->path)); c->host_port = port_to_connect; c->listening_port = listen_port; success = 1; } if (success == 0) - error("channel_request_forwarding: cannot listen to port: %d", + error("channel_setup_fwd_listener: cannot listen to port: %d", listen_port); freeaddrinfo(aitop); return success; } +int +channel_cancel_rport_listener(const char *host, u_short port) +{ + u_int i; + int found = 0; + + for (i = 0; i < channels_alloc; i++) { + Channel *c = channels[i]; + + if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER && + strncmp(c->path, host, sizeof(c->path)) == 0 && + c->listening_port == port) { + debug2("%s: close channel %d", __func__, i); + channel_free(c); + found = 1; + } + } + + return (found); +} + +/* protocol local port fwd, used by ssh (and sshd in v1) */ +int +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, + listen_host, listen_port, host_to_connect, port_to_connect, + gateway_ports); +} + +/* protocol v2 remote port fwd, used by sshd */ +int +channel_setup_remote_fwd_listener(const char *listen_address, + u_short listen_port, int gateway_ports) +{ + return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER, + listen_address, listen_port, NULL, 0, gateway_ports); +} + /* * Initiate forwarding of connections to port "port" on remote host through * the secure channel to host:port from local side. */ 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 payload_len, type, success = 0; + int type, success = 0; /* Record locally that connection to this host/port is permitted. */ if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) @@ -2191,10 +2373,17 @@ 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(0); /* boolean: want reply */ + packet_put_char(1); /* boolean: want reply */ packet_put_cstring(address_to_bind); packet_put_int(listen_port); packet_send(); @@ -2210,13 +2399,13 @@ channel_request_remote_forwarding(u_short listen_port, packet_write_wait(); /* Wait for response from the remote side. */ - type = packet_read(&payload_len); + type = packet_read(); switch (type) { case SSH_SMSG_SUCCESS: success = 1; break; case SSH_SMSG_FAILURE: - log("Warning: Server denied remote port forwarding."); + logit("Warning: Server denied remote port forwarding."); break; default: /* Unknown packet */ @@ -2232,6 +2421,40 @@ channel_request_remote_forwarding(u_short listen_port, } } +/* + * Request cancellation of remote forwarding of connection host:port from + * local side. + */ +void +channel_request_rforward_cancel(const char *host, u_short port) +{ + int i; + + if (!compat20) + return; + + for (i = 0; i < num_permitted_opens; i++) { + if (permitted_opens[i].host_to_connect != NULL && + permitted_opens[i].listen_port == port) + break; + } + if (i >= num_permitted_opens) { + debug("%s: requested forward not found", __func__); + return; + } + packet_start(SSH2_MSG_GLOBAL_REQUEST); + packet_put_cstring("cancel-tcpip-forward"); + packet_put_char(0); + packet_put_cstring(host == NULL ? "" : host); + packet_put_int(port); + packet_send(); + + permitted_opens[i].listen_port = 0; + permitted_opens[i].port_to_connect = 0; + free(permitted_opens[i].host_to_connect); + permitted_opens[i].host_to_connect = NULL; +} + /* * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates * listening for the port, and sends back a success reply (or disconnect @@ -2255,11 +2478,16 @@ channel_input_port_forward_request(int is_root, int gateway_ports) * privileged port. */ if (port < IPPORT_RESERVED && !is_root) - packet_disconnect("Requested forwarding of port %d but user is not root.", - port); + packet_disconnect( + "Requested forwarding of port %d but user is not root.", + port); + if (host_port == 0) + packet_disconnect("Dynamic forwarding denied."); #endif + /* Initiate forwarding */ - channel_request_local_forwarding(port, hostname, host_port, gateway_ports); + channel_setup_local_fwd_listener(NULL, port, hostname, + host_port, gateway_ports); /* Free the argument string. */ xfree(hostname); @@ -2297,7 +2525,8 @@ channel_clear_permitted_opens(void) int i; for (i = 0; i < num_permitted_opens; i++) - xfree(permitted_opens[i].host_to_connect); + if (permitted_opens[i].host_to_connect != NULL) + xfree(permitted_opens[i].host_to_connect); num_permitted_opens = 0; } @@ -2329,13 +2558,16 @@ connect_to(const char *host, u_short port) error("connect_to: getnameinfo failed"); continue; } - sock = socket(ai->ai_family, SOCK_STREAM, 0); + sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); if (sock < 0) { - error("socket: %.100s", strerror(errno)); + if (ai->ai_next == NULL) + error("socket: %.100s", strerror(errno)); + else + verbose("socket: %.100s", strerror(errno)); continue; } - if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) - fatal("connect_to: F_SETFL: %s", strerror(errno)); + if (set_nonblock(sock) == -1) + fatal("%s: set_nonblock(%d)", __func__, sock); if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 && errno != EINPROGRESS) { error("connect_to %.100s port %s: %.100s", ntop, strport, @@ -2352,6 +2584,7 @@ connect_to(const char *host, u_short port) return -1; } /* success */ + set_nodelay(sock); return sock; } @@ -2361,7 +2594,8 @@ channel_connect_by_listen_address(u_short listen_port) int i; for (i = 0; i < num_permitted_opens; i++) - if (permitted_opens[i].listen_port == listen_port) + if (permitted_opens[i].host_to_connect != NULL && + permitted_opens[i].listen_port == listen_port) return connect_to( permitted_opens[i].host_to_connect, permitted_opens[i].port_to_connect); @@ -2379,74 +2613,103 @@ channel_connect_to(const char *host, u_short port) permit = all_opens_permitted; if (!permit) { for (i = 0; i < num_permitted_opens; i++) - if (permitted_opens[i].port_to_connect == port && + if (permitted_opens[i].host_to_connect != NULL && + permitted_opens[i].port_to_connect == port && strcmp(permitted_opens[i].host_to_connect, host) == 0) permit = 1; } if (!permit) { - log("Received request to connect to host %.100s port %d, " + logit("Received request to connect to host %.100s port %d, " "but the request was denied.", host, port); return -1; } return connect_to(host, port); } +void +channel_send_window_changes(void) +{ + u_int i; + struct winsize ws; + + for (i = 0; i < channels_alloc; i++) { + if (channels[i] == NULL || !channels[i]->client_tty || + channels[i]->type != SSH_CHANNEL_OPEN) + continue; + if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0) + continue; + channel_request_start(i, "window-change", 0); + packet_put_int(ws.ws_col); + packet_put_int(ws.ws_row); + packet_put_int(ws.ws_xpixel); + packet_put_int(ws.ws_ypixel); + packet_send(); + } +} + /* -- X11 forwarding */ /* * Creates an internet domain socket for listening for X11 connections. - * Returns a suitable value for the DISPLAY variable, or NULL if an error - * occurs. + * Returns 0 and a suitable display number for the DISPLAY variable + * stored in display_numberp , or -1 if an error occurs. */ -char * -x11_create_display_inet(int screen_number, int x11_display_offset) +int +x11_create_display_inet(int x11_display_offset, int x11_use_localhost, + int single_connection, u_int *display_numberp) { + Channel *nc = NULL; int display_number, sock; u_short port; struct addrinfo hints, *ai, *aitop; char strport[NI_MAXSERV]; int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; - char display[512]; - char hostname[MAXHOSTNAMELEN]; for (display_number = x11_display_offset; - display_number < MAX_DISPLAYS; - display_number++) { + display_number < MAX_DISPLAYS; + display_number++) { port = 6000 + display_number; memset(&hints, 0, sizeof(hints)); hints.ai_family = IPv4or6; - hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */ + hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE; hints.ai_socktype = SOCK_STREAM; snprintf(strport, sizeof strport, "%d", port); if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { error("getaddrinfo: %.100s", gai_strerror(gaierr)); - return NULL; + return -1; } for (ai = aitop; ai; ai = ai->ai_next) { if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) continue; - sock = socket(ai->ai_family, SOCK_STREAM, 0); + sock = socket(ai->ai_family, ai->ai_socktype, + ai->ai_protocol); if (sock < 0) { if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) { error("socket: %.100s", strerror(errno)); - return NULL; + freeaddrinfo(aitop); + return -1; } else { debug("x11_create_display_inet: Socket family %d not supported", ai->ai_family); continue; } } +#ifdef IPV6_V6ONLY + if (ai->ai_family == AF_INET6) { + int on = 1; + if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) + error("setsockopt IPV6_V6ONLY: %.100s", strerror(errno)); + } +#endif if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { - debug("bind port %d: %.100s", port, strerror(errno)); - shutdown(sock, SHUT_RDWR); + debug2("bind port %d: %.100s", port, strerror(errno)); close(sock); if (ai->ai_next) continue; for (n = 0; n < num_socks; n++) { - shutdown(socks[n], SHUT_RDWR); close(socks[n]); } num_socks = 0; @@ -2457,7 +2720,12 @@ x11_create_display_inet(int screen_number, int x11_display_offset) if (num_socks == NUM_SOCKS) break; #else - break; + if (x11_use_localhost) { + if (num_socks == NUM_SOCKS) + break; + } else { + break; + } #endif } freeaddrinfo(aitop); @@ -2466,103 +2734,48 @@ x11_create_display_inet(int screen_number, int x11_display_offset) } if (display_number >= MAX_DISPLAYS) { error("Failed to allocate internet-domain X11 display socket."); - return NULL; + return -1; } /* Start listening for connections on the socket. */ for (n = 0; n < num_socks; n++) { sock = socks[n]; - if (listen(sock, 5) < 0) { + if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { error("listen: %.100s", strerror(errno)); - shutdown(sock, SHUT_RDWR); - close(sock); - return NULL; - } - } - - /* Set up a suitable value for the DISPLAY variable. */ - if (gethostname(hostname, sizeof(hostname)) < 0) - fatal("gethostname: %.100s", strerror(errno)); - -#ifdef IPADDR_IN_DISPLAY - /* - * HPUX detects the local hostname in the DISPLAY variable and tries - * to set up a shared memory connection to the server, which it - * incorrectly supposes to be local. - * - * The workaround - as used in later $$H and other programs - is - * is to set display to the host's IP address. - */ - { - struct hostent *he; - struct in_addr my_addr; - - he = gethostbyname(hostname); - if (he == NULL) { - error("[X11-broken-fwd-hostname-workaround] Could not get " - "IP address for hostname %s.", hostname); - - packet_send_debug("[X11-broken-fwd-hostname-workaround]" - "Could not get IP address for hostname %s.", hostname); - - shutdown(sock, SHUT_RDWR); close(sock); - - return NULL; + return -1; } - - memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); - - /* Set DISPLAY to :screen.display */ - snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr), - display_number, screen_number); } -#else /* IPADDR_IN_DISPLAY */ - /* Just set DISPLAY to hostname:screen.display */ - snprintf(display, sizeof display, "%.400s:%d.%d", hostname, - display_number, screen_number); -#endif /* IPADDR_IN_DISPLAY */ /* Allocate a channel for each socket. */ for (n = 0; n < num_socks; n++) { sock = socks[n]; - (void) channel_new("x11 listener", + nc = channel_new("x11 listener", SSH_CHANNEL_X11_LISTENER, sock, sock, -1, CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, - 0, xstrdup("X11 inet listener"), 1); + 0, "X11 inet listener", 1); + nc->single_connection = single_connection; } - /* Return a suitable value for the DISPLAY environment variable. */ - return xstrdup(display); + /* Return the display number for the DISPLAY environment variable. */ + *display_numberp = display_number; + return (0); } -#ifndef X_UNIX_PATH -#define X_UNIX_PATH "/tmp/.X11-unix/X" -#endif - static int connect_local_xsocket(u_int dnr) { - static const char *const x_sockets[] = { - X_UNIX_PATH "%u", - "/var/X/.X11-unix/X" "%u", - "/usr/spool/sockets/X11/" "%u", - NULL - }; int sock; struct sockaddr_un addr; - const char *const * path; - for (path = x_sockets; *path; ++path) { - sock = socket(AF_UNIX, SOCK_STREAM, 0); - if (sock < 0) - error("socket: %.100s", strerror(errno)); - memset(&addr, 0, sizeof(addr)); - addr.sun_family = AF_UNIX; - snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr); - if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) - return sock; - close(sock); - } + sock = socket(AF_UNIX, SOCK_STREAM, 0); + if (sock < 0) + error("socket: %.100s", strerror(errno)); + memset(&addr, 0, sizeof(addr)); + addr.sun_family = AF_UNIX; + snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr); + if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) + return sock; + close(sock); error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); return -1; } @@ -2597,7 +2810,7 @@ x11_connect_display(void) /* Connect to the unix domain socket. */ if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { error("Could not parse display number from DISPLAY: %.100s", - display); + display); return -1; } /* Create a socket. */ @@ -2612,8 +2825,7 @@ x11_connect_display(void) * Connect to an inet socket. The DISPLAY value is supposedly * hostname:d[.s], where hostname may also be numeric IP address. */ - strncpy(buf, display, sizeof(buf)); - buf[sizeof(buf) - 1] = 0; + strlcpy(buf, display, sizeof(buf)); cp = strchr(buf, ':'); if (!cp) { error("Could not find ':' in DISPLAY: %.100s", display); @@ -2623,7 +2835,7 @@ x11_connect_display(void) /* buf now contains the host name. But first we parse the display number. */ if (sscanf(cp + 1, "%d", &display_number) != 1) { error("Could not parse display number from DISPLAY: %.100s", - display); + display); return -1; } @@ -2638,14 +2850,14 @@ x11_connect_display(void) } for (ai = aitop; ai; ai = ai->ai_next) { /* Create a socket. */ - sock = socket(ai->ai_family, SOCK_STREAM, 0); + sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); if (sock < 0) { - debug("socket: %.100s", strerror(errno)); + debug2("socket: %.100s", strerror(errno)); continue; } /* Connect it to the display. */ if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { - debug("connect %.100s port %d: %.100s", buf, + debug2("connect %.100s port %d: %.100s", buf, 6000 + display_number, strerror(errno)); close(sock); continue; @@ -2659,6 +2871,7 @@ x11_connect_display(void) strerror(errno)); return -1; } + set_nodelay(sock); return sock; } @@ -2669,7 +2882,7 @@ x11_connect_display(void) */ void -x11_input_open(int type, int plen, void *ctxt) +x11_input_open(int type, u_int32_t seq, void *ctxt) { Channel *c = NULL; int remote_id, sock = 0; @@ -2684,7 +2897,7 @@ x11_input_open(int type, int plen, void *ctxt) } else { remote_host = xstrdup("unknown (remote did not supply name)"); } - packet_done(); + packet_check_eom(); /* Obtain a connection to the real X display. */ sock = x11_connect_display(); @@ -2693,14 +2906,10 @@ x11_input_open(int type, int plen, void *ctxt) c = channel_new("connected x11 socket", SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0, remote_host, 1); - if (c == NULL) { - error("x11_input_open: channel_new failed"); - close(sock); - } else { - c->remote_id = remote_id; - c->force_drain = 1; - } + c->remote_id = remote_id; + c->force_drain = 1; } + xfree(remote_host); if (c == NULL) { /* Send refusal to the remote host. */ packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); @@ -2716,10 +2925,11 @@ x11_input_open(int type, int plen, void *ctxt) /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ void -deny_input_open(int type, int plen, void *ctxt) +deny_input_open(int type, u_int32_t seq, void *ctxt) { int rchan = packet_get_int(); - switch(type){ + + switch (type) { case SSH_SMSG_AGENT_OPEN: error("Warning: ssh server tried agent forwarding."); break; @@ -2727,7 +2937,7 @@ deny_input_open(int type, int plen, void *ctxt) error("Warning: ssh server tried X11 forwarding."); break; default: - error("deny_input_open: type %d plen %d", type, plen); + error("deny_input_open: type %d", type); break; } error("Warning: this is probably a break in attempt by a malicious server."); @@ -2750,7 +2960,7 @@ x11_request_forwarding_with_spoofing(int client_session_id, char *new_data; int screen_number; const char *cp; - u_int32_t rand = 0; + u_int32_t rnd = 0; cp = getenv("DISPLAY"); if (cp) @@ -2775,10 +2985,10 @@ x11_request_forwarding_with_spoofing(int client_session_id, if (sscanf(data + 2 * i, "%2x", &value) != 1) fatal("x11_request_forwarding: bad authentication data: %.100s", data); if (i % 4 == 0) - rand = arc4random(); + rnd = arc4random(); x11_saved_data[i] = value; - x11_fake_data[i] = rand & 0xff; - rand >>= 8; + x11_fake_data[i] = rnd & 0xff; + rnd >>= 8; } x11_saved_data_len = data_len; x11_fake_data_len = data_len; @@ -2817,162 +3027,3 @@ auth_request_forwarding(void) packet_send(); packet_write_wait(); } - -/* - * Returns the name of the forwarded authentication socket. Returns NULL if - * there is no forwarded authentication socket. The returned value points to - * a static buffer. - */ - -char * -auth_get_socket_name(void) -{ - return auth_sock_name; -} - -/* removes the agent forwarding socket */ - -void -auth_sock_cleanup_proc(void *_pw) -{ - struct passwd *pw = _pw; - - if (auth_sock_name) { - temporarily_use_uid(pw); - unlink(auth_sock_name); - rmdir(auth_sock_dir); - auth_sock_name = NULL; - restore_uid(); - } -} - -/* - * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. - * This starts forwarding authentication requests. - */ - -int -auth_input_request_forwarding(struct passwd * pw) -{ - Channel *nc; - int sock; - struct sockaddr_un sunaddr; - - if (auth_get_socket_name() != NULL) { - error("authentication forwarding requested twice."); - return 0; - } - - /* Temporarily drop privileged uid for mkdir/bind. */ - temporarily_use_uid(pw); - - /* Allocate a buffer for the socket name, and format the name. */ - auth_sock_name = xmalloc(MAXPATHLEN); - auth_sock_dir = xmalloc(MAXPATHLEN); - strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); - - /* Create private directory for socket */ - if (mkdtemp(auth_sock_dir) == NULL) { - packet_send_debug("Agent forwarding disabled: " - "mkdtemp() failed: %.100s", strerror(errno)); - restore_uid(); - xfree(auth_sock_name); - xfree(auth_sock_dir); - auth_sock_name = NULL; - auth_sock_dir = NULL; - return 0; - } - snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d", - auth_sock_dir, (int) getpid()); - - /* delete agent socket on fatal() */ - fatal_add_cleanup(auth_sock_cleanup_proc, pw); - - /* Create the socket. */ - sock = socket(AF_UNIX, SOCK_STREAM, 0); - if (sock < 0) - packet_disconnect("socket: %.100s", strerror(errno)); - - /* Bind it to the name. */ - memset(&sunaddr, 0, sizeof(sunaddr)); - sunaddr.sun_family = AF_UNIX; - strncpy(sunaddr.sun_path, auth_sock_name, - sizeof(sunaddr.sun_path)); - - if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) - packet_disconnect("bind: %.100s", strerror(errno)); - - /* Restore the privileged uid. */ - restore_uid(); - - /* Start listening on the socket. */ - if (listen(sock, 5) < 0) - packet_disconnect("listen: %.100s", strerror(errno)); - - /* Allocate a channel for the authentication agent socket. */ - nc = channel_new("auth socket", - SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, - CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, - 0, xstrdup("auth socket"), 1); - if (nc == NULL) { - error("auth_input_request_forwarding: channel_new failed"); - auth_sock_cleanup_proc(pw); - fatal_remove_cleanup(auth_sock_cleanup_proc, pw); - close(sock); - return 0; - } - strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); - return 1; -} - -/* This is called to process an SSH_SMSG_AGENT_OPEN message. */ - -void -auth_input_open_request(int type, int plen, void *ctxt) -{ - Channel *c = NULL; - int remote_id, sock; - char *name; - - packet_integrity_check(plen, 4, type); - - /* Read the remote channel number from the message. */ - remote_id = packet_get_int(); - - /* - * Get a connection to the local authentication agent (this may again - * get forwarded). - */ - sock = ssh_get_authentication_socket(); - - /* - * If we could not connect the agent, send an error message back to - * the server. This should never happen unless the agent dies, - * because authentication forwarding is only enabled if we have an - * agent. - */ - if (sock >= 0) { - name = xstrdup("authentication agent connection"); - c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, - -1, 0, 0, 0, name, 1); - if (c == NULL) { - error("auth_input_open_request: channel_new failed"); - xfree(name); - close(sock); - } else { - c->remote_id = remote_id; - c->force_drain = 1; - } - } - if (c == NULL) { - packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); - packet_put_int(remote_id); - } else { - /* Send a confirmation to the remote host. */ - debug("Forwarding authentication connection."); - packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); - packet_put_int(remote_id); - packet_put_int(c->self); - } - packet_send(); -}