*/
#include "includes.h"
-RCSID("$OpenBSD: channels.c,v 1.95 2001/02/28 21:27:48 markus Exp $");
+RCSID("$OpenBSD: channels.c,v 1.113 2001/05/04 23:47:33 markus Exp $");
#include <openssl/rsa.h>
#include <openssl/dsa.h>
#include "packet.h"
#include "xmalloc.h"
#include "buffer.h"
+#include "bufaux.h"
#include "uidswap.h"
#include "log.h"
#include "misc.h"
* Pointer to an array containing all allocated channels. The array is
* dynamically extended as needed.
*/
-static Channel *channels = NULL;
+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 are marked with type
- * SSH_CHANNEL_FREE.
+ * initialized (at least the type field); unused slots set to NULL
*/
static int channels_alloc = 0;
/*
* Maximum file descriptor value used in any of the channels. This is
- * updated in channel_allocate.
+ * updated in channel_new.
*/
static int channel_max_fd = 0;
/* AF_UNSPEC or AF_INET or AF_INET6 */
extern int IPv4or6;
+void port_open_helper(Channel *c, char *rtype);
+
/* Sets specific protocol options. */
void
have_hostname_in_open = hostname_in_open;
}
-/*
- * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually
- * called by the server, because the user could connect to any port anyway,
- * and the server has no way to know but to trust the client anyway.
- */
-
-void
-channel_permit_all_opens()
-{
- all_opens_permitted = 1;
-}
-
/* lookup channel by id */
Channel *
channel_lookup(int id)
{
Channel *c;
+
if (id < 0 || id > channels_alloc) {
log("channel_lookup: %d: bad id", id);
return NULL;
}
- c = &channels[id];
- if (c->type == SSH_CHANNEL_FREE) {
+ c = channels[id];
+ if (c == NULL) {
log("channel_lookup: %d: bad id: channel free", id);
return NULL;
}
* remote_name to be freed.
*/
-int
+Channel *
channel_new(char *ctype, int type, int rfd, int wfd, int efd,
int window, int maxpack, int extusage, char *remote_name, int nonblock)
{
if (channels_alloc == 0) {
chan_init();
channels_alloc = 10;
- channels = xmalloc(channels_alloc * sizeof(Channel));
+ channels = xmalloc(channels_alloc * sizeof(Channel *));
for (i = 0; i < channels_alloc; i++)
- channels[i].type = SSH_CHANNEL_FREE;
+ channels[i] = NULL;
/*
* Kludge: arrange a call to channel_stop_listening if we
* terminate with fatal().
}
/* Try to find a free slot where to put the new channel. */
for (found = -1, i = 0; i < channels_alloc; i++)
- if (channels[i].type == SSH_CHANNEL_FREE) {
+ if (channels[i] == NULL) {
/* Found a free slot. */
found = i;
break;
found = channels_alloc;
channels_alloc += 10;
debug2("channel: expanding %d", channels_alloc);
- channels = xrealloc(channels, channels_alloc * sizeof(Channel));
+ channels = xrealloc(channels, channels_alloc * sizeof(Channel *));
for (i = found; i < channels_alloc; i++)
- channels[i].type = SSH_CHANNEL_FREE;
+ channels[i] = NULL;
}
- /* Initialize and return new channel number. */
- c = &channels[found];
+ /* Initialize and return new channel. */
+ c = channels[found] = xmalloc(sizeof(Channel));
buffer_init(&c->input);
buffer_init(&c->output);
buffer_init(&c->extended);
c->dettach_user = NULL;
c->input_filter = NULL;
debug("channel %d: new [%s]", found, remote_name);
- return found;
-}
-/* old interface XXX */
-int
-channel_allocate(int type, int sock, char *remote_name)
-{
- return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name, 1);
+ return c;
}
-
/* Close all channel fd/socket. */
void
/* Free the channel and close its fd/socket. */
void
-channel_free(int id)
+channel_free(Channel *c)
{
- Channel *c = channel_lookup(id);
- char *s = channel_open_message();
+ char *s;
- if (c == NULL)
- packet_disconnect("channel free: bad local channel %d", id);
- debug("channel_free: channel %d: status: %s", id, s);
+ s = channel_open_message();
+ debug("channel_free: channel %d: status: %s", c->self, s);
xfree(s);
if (c->dettach_user != NULL) {
- debug("channel_free: channel %d: dettaching channel user", id);
+ debug("channel_free: channel %d: dettaching channel user", c->self);
c->dettach_user(c->self, NULL);
}
if (c->sock != -1)
buffer_free(&c->input);
buffer_free(&c->output);
buffer_free(&c->extended);
- c->type = SSH_CHANNEL_FREE;
if (c->remote_name) {
xfree(c->remote_name);
c->remote_name = NULL;
}
+ channels[c->self] = NULL;
+ xfree(c);
}
/*
packet_put_int(c->remote_id);
packet_send();
c->type = SSH_CHANNEL_CLOSED;
- debug("Closing channel %d after input drain.", c->self);
+ debug("channel %d: closing after input drain.", c->self);
}
}
channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
{
if (buffer_len(&c->output) == 0)
- channel_free(c->self);
+ chan_mark_dead(c);
else
FD_SET(c->sock, writeset);
}
* We have received an X11 connection that has bad
* authentication information.
*/
- log("X11 connection rejected because of wrong authentication.\r\n");
+ log("X11 connection rejected because of wrong authentication.");
buffer_clear(&c->input);
buffer_clear(&c->output);
close(c->sock);
}
}
+/* try to decode a socks4 header */
+int
+channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ u_char *p, *host;
+ int len, have, i, found;
+ char username[256];
+ struct {
+ u_int8_t version;
+ u_int8_t command;
+ u_int16_t dest_port;
+ struct in_addr dest_addr;
+ } s4_req, s4_rsp;
+
+ debug2("channel %d: decode socks4", c->self);
+
+ have = buffer_len(&c->input);
+ len = sizeof(s4_req);
+ if (have < len)
+ return 0;
+ p = buffer_ptr(&c->input);
+ for (found = 0, i = len; i < have; i++) {
+ if (p[i] == '\0') {
+ found = 1;
+ break;
+ }
+ if (i > 1024) {
+ /* the peer is probably sending garbage */
+ debug("channel %d: decode socks4: too long",
+ c->self);
+ return -1;
+ }
+ }
+ if (!found)
+ return 0;
+ buffer_get(&c->input, (char *)&s4_req.version, 1);
+ buffer_get(&c->input, (char *)&s4_req.command, 1);
+ buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
+ buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
+ have = buffer_len(&c->input);
+ p = buffer_ptr(&c->input);
+ len = strlen(p);
+ debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
+ if (len > have)
+ fatal("channel %d: decode socks4: len %d > have %d",
+ c->self, len, have);
+ strlcpy(username, p, sizeof(username));
+ buffer_consume(&c->input, len);
+ buffer_consume(&c->input, 1); /* trailing '\0' */
+
+ 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",
+ c->self, host, c->host_port, s4_req.command);
+
+ if (s4_req.command != 1) {
+ debug("channel %d: cannot handle: socks4 cn %d",
+ c->self, s4_req.command);
+ return -1;
+ }
+ s4_rsp.version = 0; /* vn: 0 for reply */
+ s4_rsp.command = 90; /* cd: req granted */
+ s4_rsp.dest_port = 0; /* ignored */
+ s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
+ buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
+ return 1;
+}
+
+/* dynamic port forwarding */
+void
+channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ u_char *p;
+ int have, ret;
+
+ have = buffer_len(&c->input);
+
+ 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) {
+ /* need more */
+ FD_SET(c->sock, readset);
+ return;
+ }
+ /* try to guess the protocol */
+ p = buffer_ptr(&c->input);
+ switch (p[0]) {
+ case 0x04:
+ ret = channel_decode_socks4(c, readset, writeset);
+ break;
+ default:
+ ret = -1;
+ break;
+ }
+ if (ret < 0) {
+ chan_mark_dead(c);
+ } else if (ret == 0) {
+ debug2("channel %d: pre_dynamic: need more", c->self);
+ /* need more */
+ FD_SET(c->sock, readset);
+ } else {
+ /* switch to the next state */
+ c->type = SSH_CHANNEL_OPENING;
+ port_open_helper(c, "direct-tcpip");
+ }
+}
+
/* This is our fake X11 server socket. */
void
channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
{
+ Channel *nc;
struct sockaddr addr;
- int newsock, newch;
+ int newsock;
socklen_t addrlen;
char buf[16384], *remote_ipaddr;
int remote_port;
snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
remote_ipaddr, remote_port);
- newch = channel_new("x11",
+ 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;
+ }
if (compat20) {
packet_start(SSH2_MSG_CHANNEL_OPEN);
packet_put_cstring("x11");
- packet_put_int(newch);
+ packet_put_int(nc->self);
packet_put_int(c->local_window_max);
packet_put_int(c->local_maxpacket);
/* originator ipaddr and port */
packet_send();
} else {
packet_start(SSH_SMSG_X11_OPEN);
- packet_put_int(newch);
+ packet_put_int(nc->self);
if (have_hostname_in_open)
packet_put_string(buf, strlen(buf));
packet_send();
}
}
+void
+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);
+
+ direct = (strcmp(rtype, "direct-tcpip") == 0);
+
+ snprintf(buf, sizeof buf,
+ "%s: listening port %d for %.100s port %d, "
+ "connect from %.200s port %d",
+ rtype, c->listening_port, c->path, c->host_port,
+ remote_ipaddr, remote_port);
+
+ xfree(c->remote_name);
+ c->remote_name = xstrdup(buf);
+
+ if (compat20) {
+ packet_start(SSH2_MSG_CHANNEL_OPEN);
+ packet_put_cstring(rtype);
+ packet_put_int(c->self);
+ packet_put_int(c->local_window_max);
+ packet_put_int(c->local_maxpacket);
+ if (direct) {
+ /* target host, port */
+ packet_put_cstring(c->path);
+ packet_put_int(c->host_port);
+ } else {
+ /* listen address, port */
+ packet_put_cstring(c->path);
+ packet_put_int(c->listening_port);
+ }
+ /* originator host and port */
+ packet_put_cstring(remote_ipaddr);
+ packet_put_int(remote_port);
+ packet_send();
+ } else {
+ packet_start(SSH_MSG_PORT_OPEN);
+ packet_put_int(c->self);
+ packet_put_cstring(c->path);
+ packet_put_int(c->host_port);
+ if (have_hostname_in_open)
+ packet_put_cstring(c->remote_name);
+ packet_send();
+ }
+ xfree(remote_ipaddr);
+}
+
/*
* This socket is listening for connections to a forwarded TCP/IP port.
*/
void
channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
{
+ Channel *nc;
struct sockaddr addr;
- int newsock, newch;
+ int newsock, nextstate;
socklen_t addrlen;
- char buf[1024], *remote_ipaddr, *rtype;
- int remote_port;
-
- rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ?
- "forwarded-tcpip" : "direct-tcpip";
+ char *rtype;
if (FD_ISSET(c->sock, readset)) {
debug("Connection to port %d forwarding "
"to %.100s port %d requested.",
c->listening_port, c->path, c->host_port);
+
+ rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ?
+ "forwarded-tcpip" : "direct-tcpip";
+ nextstate = (c->host_port == 0) ? SSH_CHANNEL_DYNAMIC :
+ SSH_CHANNEL_OPENING;
+
addrlen = sizeof(addr);
newsock = accept(c->sock, &addr, &addrlen);
if (newsock < 0) {
error("accept: %.100s", strerror(errno));
return;
}
- remote_ipaddr = get_peer_ipaddr(newsock);
- remote_port = get_peer_port(newsock);
- snprintf(buf, sizeof buf,
- "listen port %d for %.100s port %d, "
- "connect from %.200s port %d",
- c->listening_port, c->path, c->host_port,
- remote_ipaddr, remote_port);
-
- newch = channel_new(rtype,
- SSH_CHANNEL_OPENING, newsock, newsock, -1,
+ nc = channel_new(rtype,
+ nextstate, newsock, newsock, -1,
c->local_window_max, c->local_maxpacket,
- 0, xstrdup(buf), 1);
- if (compat20) {
- packet_start(SSH2_MSG_CHANNEL_OPEN);
- packet_put_cstring(rtype);
- packet_put_int(newch);
- packet_put_int(c->local_window_max);
- packet_put_int(c->local_maxpacket);
- if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
- /* listen address, port */
- packet_put_string(c->path, strlen(c->path));
- packet_put_int(c->listening_port);
- } else {
- /* target host, port */
- packet_put_string(c->path, strlen(c->path));
- packet_put_int(c->host_port);
- }
- /* originator host and port */
- packet_put_cstring(remote_ipaddr);
- packet_put_int(remote_port);
- packet_send();
- } else {
- packet_start(SSH_MSG_PORT_OPEN);
- packet_put_int(newch);
- packet_put_string(c->path, strlen(c->path));
- packet_put_int(c->host_port);
- if (have_hostname_in_open) {
- packet_put_string(buf, strlen(buf));
- }
- packet_send();
+ 0, xstrdup(rtype), 1);
+ if (nc == NULL) {
+ error("channel_post_port_listener: no new channel:");
+ close(newsock);
+ return;
}
- xfree(remote_ipaddr);
+ nc->listening_port = c->listening_port;
+ nc->host_port = c->host_port;
+ strlcpy(nc->path, c->path, sizeof(nc->path));
+
+ if (nextstate != SSH_CHANNEL_DYNAMIC)
+ port_open_helper(nc, rtype);
}
}
void
channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
{
+ Channel *nc;
+ int newsock;
struct sockaddr addr;
- int newsock, newch;
socklen_t addrlen;
if (FD_ISSET(c->sock, readset)) {
error("accept from auth socket: %.100s", strerror(errno));
return;
}
- newch = channel_new("accepted auth socket",
+ nc = channel_new("accepted auth socket",
SSH_CHANNEL_OPENING, newsock, newsock, -1,
c->local_window_max, c->local_maxpacket,
0, xstrdup("accepted auth socket"), 1);
+ if (nc == NULL) {
+ error("channel_post_auth_listener: channel_new failed");
+ close(newsock);
+ }
if (compat20) {
packet_start(SSH2_MSG_CHANNEL_OPEN);
packet_put_cstring("auth-agent@openssh.com");
- packet_put_int(newch);
+ packet_put_int(nc->self);
packet_put_int(c->local_window_max);
packet_put_int(c->local_maxpacket);
} else {
packet_start(SSH_SMSG_AGENT_OPEN);
- packet_put_int(newch);
+ packet_put_int(nc->self);
}
packet_send();
}
debug("getsockopt SO_ERROR failed");
} else {
if (err == 0) {
- debug("channel %d: connected)", c->self);
+ debug("channel %d: connected", c->self);
} else {
debug("channel %d: not connected: %s",
c->self, strerror(err));
if (len <= 0) {
debug("channel %d: read<=0 rfd %d len %d",
c->self, c->rfd, len);
- if (compat13) {
+ if (c->type != SSH_CHANNEL_OPEN) {
+ debug("channel %d: not open", c->self);
+ chan_mark_dead(c);
+ return -1;
+ } else if (compat13) {
buffer_consume(&c->output, buffer_len(&c->output));
c->type = SSH_CHANNEL_INPUT_DRAINING;
- debug("Channel %d status set to input draining.", c->self);
+ debug("channel %d: status set to input draining.", c->self);
} else {
chan_read_failed(c);
}
}
if(c->input_filter != NULL) {
if (c->input_filter(c, buf, len) == -1) {
- debug("filter stops channel %d", c->self);
+ debug("channel %d: filter stops", c->self);
chan_read_failed(c);
}
} else {
if (len < 0 && (errno == EINTR || errno == EAGAIN))
return 1;
if (len <= 0) {
- if (compat13) {
+ if (c->type != SSH_CHANNEL_OPEN) {
+ debug("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 status set to input draining.", c->self);
+ debug("channel %d: status set to input draining.", c->self);
c->type = SSH_CHANNEL_INPUT_DRAINING;
} else {
chan_write_failed(c);
!(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
/*
* Simulate echo to reduce the impact of
- * traffic analysis. We need too match the
+ * traffic analysis. We need to match the
* size of a SSH2_MSG_CHANNEL_DATA message
* (4 byte channel id + data)
*/
int
channel_check_window(Channel *c)
{
- if (!(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
+ if (c->type == SSH_CHANNEL_OPEN &&
+ !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
c->local_window < c->local_window_max/2 &&
c->local_consumed > 0) {
packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
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_PORT_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;
}
void
channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
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_X11_LISTENER] = &channel_post_x11_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;
}
void
channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
+ channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
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_CONNECTING] = &channel_post_connecting;
+ channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
}
void
did_init = 1;
}
for (i = 0; i < channels_alloc; i++) {
- c = &channels[i];
- if (c->type == SSH_CHANNEL_FREE)
+ c = channels[i];
+ if (c == NULL)
continue;
if (ftab[c->type] == NULL)
continue;
if (c->extended_usage == CHAN_EXTENDED_WRITE)
FD_CLR(c->efd, writeset);
}
- channel_free(c->self);
+ channel_free(c);
}
}
}
void
-channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp)
+channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
+ int rekeying)
{
int n;
u_int sz;
memset(*readsetp, 0, sz);
memset(*writesetp, 0, sz);
- channel_handler(channel_pre, *readsetp, *writesetp);
+ if (!rekeying)
+ channel_handler(channel_pre, *readsetp, *writesetp);
}
void
Channel *c;
for (i = 0; i < channels_alloc; i++) {
- c = &channels[i];
+
+ c = channels[i];
+ if (c == NULL)
+ continue;
/* We are only interested in channels that can have buffered incoming data. */
if (compat13) {
if (compat20 &&
(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
/* XXX is this true? */
- debug("channel %d: no data after CLOSE", c->self);
+ debug2("channel %d: no data after CLOSE", c->self);
continue;
}
Channel *c;
for (i = 0; i < channels_alloc; i++) {
- c = &channels[i];
- if (c->type == SSH_CHANNEL_OPEN) {
+ c = channels[i];
+ if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) {
debug("channel %d: big input buffer %d",
c->self, buffer_len(&c->input));
if (c->type != SSH_CHANNEL_CLOSED)
packet_disconnect("Received close confirmation for "
"non-closed channel %d (type %d).", id, c->type);
- channel_free(c->self);
+ channel_free(c);
}
void
"non-opening channel %d.", id);
if (compat20) {
reason = packet_get_int();
- if (packet_remaining() > 0) {
+ if (!(datafellows & SSH_BUG_OPENFAILURE)) {
msg = packet_get_string(NULL);
lang = packet_get_string(NULL);
}
xfree(lang);
}
/* Free the channel. This will also close the socket. */
- channel_free(id);
+ channel_free(c);
}
void
channel_stop_listening()
{
int i;
+ Channel *c;
+
for (i = 0; i < channels_alloc; i++) {
- switch (channels[i].type) {
- case SSH_CHANNEL_AUTH_SOCKET:
- close(channels[i].sock);
- unlink(channels[i].path);
- channel_free(i);
- break;
- case SSH_CHANNEL_PORT_LISTENER:
- case SSH_CHANNEL_RPORT_LISTENER:
- case SSH_CHANNEL_X11_LISTENER:
- close(channels[i].sock);
- channel_free(i);
- break;
- default:
- break;
+ c = channels[i];
+ if (c != NULL) {
+ switch (c->type) {
+ case SSH_CHANNEL_AUTH_SOCKET:
+ close(c->sock);
+ unlink(c->path);
+ channel_free(c);
+ break;
+ case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
+ case SSH_CHANNEL_X11_LISTENER:
+ close(c->sock);
+ channel_free(c);
+ break;
+ default:
+ break;
+ }
}
}
}
channel_close_all()
{
int i;
+
for (i = 0; i < channels_alloc; i++)
- if (channels[i].type != SSH_CHANNEL_FREE)
- channel_close_fds(&channels[i]);
+ if (channels[i] != NULL)
+ channel_close_fds(channels[i]);
}
/* Returns true if any channel is still open. */
int
channel_still_open()
{
- u_int i;
- for (i = 0; i < channels_alloc; i++)
- switch (channels[i].type) {
- case SSH_CHANNEL_FREE:
+ int i;
+ Channel *c;
+
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c == NULL)
+ continue;
+ switch (c->type) {
case SSH_CHANNEL_X11_LISTENER:
case SSH_CHANNEL_PORT_LISTENER:
case SSH_CHANNEL_RPORT_LISTENER:
case SSH_CHANNEL_CLOSED:
case SSH_CHANNEL_AUTH_SOCKET:
+ case SSH_CHANNEL_DYNAMIC:
case SSH_CHANNEL_CONNECTING: /* XXX ??? */
continue;
case SSH_CHANNEL_LARVAL:
fatal("cannot happen: OUT_DRAIN");
return 1;
default:
- fatal("channel_still_open: bad channel type %d", channels[i].type);
+ fatal("channel_still_open: bad channel type %d", c->type);
/* NOTREACHED */
}
+ }
return 0;
}
+/* Returns the id of an open channel suitable for keepaliving */
+
+int
+channel_find_open()
+{
+ int i;
+ Channel *c;
+
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c == NULL)
+ continue;
+ switch (c->type) {
+ case SSH_CHANNEL_CLOSED:
+ case SSH_CHANNEL_DYNAMIC:
+ case SSH_CHANNEL_X11_LISTENER:
+ case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
+ case SSH_CHANNEL_OPENING:
+ continue;
+ case SSH_CHANNEL_LARVAL:
+ case SSH_CHANNEL_AUTH_SOCKET:
+ case SSH_CHANNEL_CONNECTING: /* XXX ??? */
+ case SSH_CHANNEL_OPEN:
+ case SSH_CHANNEL_X11_OPEN:
+ return i;
+ case SSH_CHANNEL_INPUT_DRAINING:
+ case SSH_CHANNEL_OUTPUT_DRAINING:
+ if (!compat13)
+ fatal("cannot happen: OUT_DRAIN");
+ return i;
+ default:
+ fatal("channel_find_open: bad channel type %d", c->type);
+ /* NOTREACHED */
+ }
+ }
+ return -1;
+}
+
+
/*
* Returns a message describing the currently open forwarded connections,
* suitable for sending to the client. The message contains crlf pairs for
channel_open_message()
{
Buffer buffer;
+ Channel *c;
+ char buf[1024], *cp;
int i;
- char buf[512], *cp;
buffer_init(&buffer);
snprintf(buf, sizeof buf, "The following connections are open:\r\n");
buffer_append(&buffer, buf, strlen(buf));
for (i = 0; i < channels_alloc; i++) {
- Channel *c = &channels[i];
+ c = channels[i];
+ if (c == NULL)
+ continue;
switch (c->type) {
- case SSH_CHANNEL_FREE:
case SSH_CHANNEL_X11_LISTENER:
case SSH_CHANNEL_PORT_LISTENER:
case SSH_CHANNEL_RPORT_LISTENER:
case SSH_CHANNEL_LARVAL:
case SSH_CHANNEL_OPENING:
case SSH_CHANNEL_CONNECTING:
+ case SSH_CHANNEL_DYNAMIC:
case SSH_CHANNEL_OPEN:
case SSH_CHANNEL_X11_OPEN:
case SSH_CHANNEL_INPUT_DRAINING:
const char *host_to_connect, u_short port_to_connect,
int gateway_ports, int remote_fwd)
{
- int success, ch, sock, on = 1, ctype;
+ Channel *c;
+ int success, sock, on = 1, ctype;
struct addrinfo hints, *ai, *aitop;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
const char *host;
ctype =SSH_CHANNEL_PORT_LISTENER;
}
- if (strlen(host) > sizeof(channels[0].path) - 1) {
+ if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
error("Forward host name too long.");
return success;
}
continue;
}
/* Allocate a channel number for the socket. */
- ch = channel_new("port listener", ctype, sock, sock, -1,
+ c = channel_new("port listener", ctype, sock, sock, -1,
CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
0, xstrdup("port listener"), 1);
- strlcpy(channels[ch].path, host, sizeof(channels[ch].path));
- channels[ch].host_port = port_to_connect;
- channels[ch].listening_port = listen_port;
+ if (c == NULL) {
+ error("channel_request_forwarding: channel_new failed");
+ close(sock);
+ continue;
+ }
+ strlcpy(c->path, host, sizeof(c->path));
+ c->host_port = port_to_connect;
+ c->listening_port = listen_port;
success = 1;
}
if (success == 0)
xfree(hostname);
}
-/* XXX move to aux.c */
+/*
+ * Permits opening to any host/port if permitted_opens[] is empty. This is
+ * usually called by the server, because the user could connect to any port
+ * anyway, and the server has no way to know but to trust the client anyway.
+ */
+void
+channel_permit_all_opens()
+{
+ if (num_permitted_opens == 0)
+ all_opens_permitted = 1;
+}
+
+void
+channel_add_permitted_opens(char *host, int port)
+{
+ if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
+ fatal("channel_request_remote_forwarding: too many forwards");
+ debug("allow port forwarding to host %s port %d", host, port);
+
+ permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
+ permitted_opens[num_permitted_opens].port_to_connect = port;
+ num_permitted_opens++;
+
+ all_opens_permitted = 0;
+}
+
+void
+channel_clear_permitted_opens(void)
+{
+ int i;
+
+ for (i = 0; i < num_permitted_opens; i++)
+ xfree(permitted_opens[i].host_to_connect);
+ num_permitted_opens = 0;
+
+}
+
+
+/* return socket to remote host, port */
int
-channel_connect_to(const char *host, u_short host_port)
+connect_to(const char *host, u_short port)
{
struct addrinfo hints, *ai, *aitop;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
memset(&hints, 0, sizeof(hints));
hints.ai_family = IPv4or6;
hints.ai_socktype = SOCK_STREAM;
- snprintf(strport, sizeof strport, "%d", host_port);
+ snprintf(strport, sizeof strport, "%d", port);
if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
- error("%.100s: unknown host (%s)", host, gai_strerror(gaierr));
+ error("connect_to %.100s: unknown host (%s)", host,
+ gai_strerror(gaierr));
return -1;
}
for (ai = aitop; ai; ai = ai->ai_next) {
continue;
if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
- error("channel_connect_to: getnameinfo failed");
+ error("connect_to: getnameinfo failed");
continue;
}
- /* Create the socket. */
sock = socket(ai->ai_family, SOCK_STREAM, 0);
if (sock < 0) {
error("socket: %.100s", strerror(errno));
}
if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
fatal("connect_to: F_SETFL: %s", strerror(errno));
- /* Connect to the host/port. */
if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
errno != EINPROGRESS) {
- error("connect %.100s port %s: %.100s", ntop, strport,
+ error("connect_to %.100s port %s: %.100s", ntop, strport,
strerror(errno));
close(sock);
continue; /* fail -- try next */
}
freeaddrinfo(aitop);
if (!ai) {
- error("connect %.100s port %d: failed.", host, host_port);
+ error("connect_to %.100s port %d: failed.", host, port);
return -1;
}
/* success */
return sock;
}
+
int
channel_connect_by_listen_adress(u_short listen_port)
{
int i;
+
for (i = 0; i < num_permitted_opens; i++)
if (permitted_opens[i].listen_port == listen_port)
- return channel_connect_to(
+ return connect_to(
permitted_opens[i].host_to_connect,
permitted_opens[i].port_to_connect);
error("WARNING: Server requests forwarding for unknown listen_port %d",
return -1;
}
+/* Check if connecting to that port is permitted and connect. */
+int
+channel_connect_to(const char *host, u_short port)
+{
+ int i, permit;
+
+ permit = all_opens_permitted;
+ if (!permit) {
+ for (i = 0; i < num_permitted_opens; i++)
+ if (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, "
+ "but the request was denied.", host, port);
+ return -1;
+ }
+ return connect_to(host, port);
+}
+
/*
* This is called after receiving PORT_OPEN message. This attempts to
* connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION
void
channel_input_port_open(int type, int plen, void *ctxt)
{
+ Channel *c = NULL;
u_short host_port;
char *host, *originator_string;
- int remote_channel, sock = -1, newch, i, denied;
- u_int host_len, originator_len;
+ int remote_id, sock = -1;
- /* Get remote channel number. */
- remote_channel = packet_get_int();
-
- /* Get host name to connect to. */
- host = packet_get_string(&host_len);
-
- /* Get port to connect to. */
+ remote_id = packet_get_int();
+ host = packet_get_string(NULL);
host_port = packet_get_int();
- /* Get remote originator name. */
if (have_hostname_in_open) {
- originator_string = packet_get_string(&originator_len);
- originator_len += 4; /* size of packet_int */
+ originator_string = packet_get_string(NULL);
} else {
originator_string = xstrdup("unknown (remote did not supply name)");
- originator_len = 0; /* no originator supplied */
}
-
- packet_integrity_check(plen,
- 4 + 4 + host_len + 4 + originator_len, SSH_MSG_PORT_OPEN);
-
- /* Check if opening that port is permitted. */
- denied = 0;
- if (!all_opens_permitted) {
- /* Go trough all permitted ports. */
- for (i = 0; i < num_permitted_opens; i++)
- if (permitted_opens[i].port_to_connect == host_port &&
- strcmp(permitted_opens[i].host_to_connect, host) == 0)
- break;
-
- /* Check if we found the requested port among those permitted. */
- if (i >= num_permitted_opens) {
- /* The port is not permitted. */
- log("Received request to connect to %.100s:%d, but the request was denied.",
- host, host_port);
- denied = 1;
+ packet_done();
+ 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;
}
}
- sock = denied ? -1 : channel_connect_to(host, host_port);
- if (sock > 0) {
- /* Allocate a channel for this connection. */
- newch = channel_allocate(SSH_CHANNEL_CONNECTING,
- sock, originator_string);
-/*XXX delay answer? */
- channels[newch].remote_id = remote_channel;
-
- packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remote_channel);
- packet_put_int(newch);
- packet_send();
- } else {
+ if (c == NULL) {
packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remote_channel);
- packet_send();
+ packet_put_int(remote_id);
+ } else {
+ /*XXX delay answer? */
+ packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
+ packet_put_int(remote_id);
+ packet_put_int(c->self);
}
+ packet_send();
xfree(host);
}
void
x11_input_open(int type, int plen, void *ctxt)
{
- int remote_channel, sock = 0, newch;
+ Channel *c = NULL;
+ int remote_id, sock = 0;
char *remote_host;
- u_int remote_len;
- /* Get remote channel number. */
- remote_channel = packet_get_int();
+ debug("Received X11 open request.");
- /* Get remote originator name. */
+ remote_id = packet_get_int();
if (have_hostname_in_open) {
- remote_host = packet_get_string(&remote_len);
- remote_len += 4;
+ remote_host = packet_get_string(NULL);
} else {
remote_host = xstrdup("unknown (remote did not supply name)");
- remote_len = 0;
}
-
- debug("Received X11 open request.");
- packet_integrity_check(plen, 4 + remote_len, SSH_SMSG_X11_OPEN);
+ packet_done();
/* Obtain a connection to the real X display. */
sock = x11_connect_display();
- if (sock == -1) {
+ if (sock != -1) {
+ /* Allocate a channel for this connection. */
+ 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;
+ }
+ }
+ if (c == NULL) {
/* Send refusal to the remote host. */
packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remote_channel);
- packet_send();
+ packet_put_int(remote_id);
} else {
- /* Allocate a channel for this connection. */
- newch = channel_allocate(
- (x11_saved_proto == NULL) ?
- SSH_CHANNEL_OPEN : SSH_CHANNEL_X11_OPEN,
- sock, remote_host);
- channels[newch].remote_id = remote_channel;
-
/* Send a confirmation to the remote host. */
packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remote_channel);
- packet_put_int(newch);
- packet_send();
+ packet_put_int(remote_id);
+ packet_put_int(c->self);
}
+ packet_send();
}
/* dummy protocol handler that denies SSH-1 requests (agent/x11) */
int
auth_input_request_forwarding(struct passwd * pw)
{
- int sock, newch;
+ Channel *nc;
+ int sock;
struct sockaddr_un sunaddr;
if (auth_get_socket_name() != NULL)
fatal("Protocol error: authentication forwarding requested twice.");
/* Temporarily drop privileged uid for mkdir/bind. */
- temporarily_use_uid(pw->pw_uid);
+ temporarily_use_uid(pw);
/* Allocate a buffer for the socket name, and format the name. */
channel_forwarded_auth_socket_name = xmalloc(MAX_SOCKET_NAME);
packet_disconnect("listen: %.100s", strerror(errno));
/* Allocate a channel for the authentication agent socket. */
- newch = channel_new("auth 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);
-
- strlcpy(channels[newch].path, channel_forwarded_auth_socket_name,
- sizeof(channels[newch].path));
+ if (nc == NULL) {
+ error("auth_input_request_forwarding: channel_new failed");
+ close(sock);
+ return 0;
+ }
+ strlcpy(nc->path, channel_forwarded_auth_socket_name, sizeof(nc->path));
return 1;
}
void
auth_input_open_request(int type, int plen, void *ctxt)
{
- int remch, sock, newch;
+ Channel *c = NULL;
+ int remote_id, sock;
char *dummyname;
packet_integrity_check(plen, 4, type);
/* Read the remote channel number from the message. */
- remch = packet_get_int();
+ remote_id = packet_get_int();
/*
* Get a connection to the local authentication agent (this may again
* because authentication forwarding is only enabled if we have an
* agent.
*/
- if (sock < 0) {
+ if (sock >= 0) {
+ dummyname = xstrdup("authentication agent connection");
+ c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, -1, 0, 0, 0, dummyname, 1);
+ if (c == NULL) {
+ error("auth_input_open_request: channel_new failed");
+ close(sock);
+ } else {
+ c->remote_id = remote_id;
+ }
+ }
+ if (c == NULL) {
packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remch);
- packet_send();
- return;
+ 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);
}
- debug("Forwarding authentication connection.");
-
- /*
- * Dummy host name. This will be freed when the channel is freed; it
- * will still be valid in the packet_put_string below since the
- * channel cannot yet be freed at that point.
- */
- dummyname = xstrdup("authentication agent connection");
-
- newch = channel_allocate(SSH_CHANNEL_OPEN, sock, dummyname);
- channels[newch].remote_id = remch;
-
- /* Send a confirmation to the remote host. */
- packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remch);
- packet_put_int(newch);
packet_send();
}
andersk / openssh.git / blobdiff