*/
#include "includes.h"
-RCSID("$OpenBSD: channels.c,v 1.198 2003/11/21 11:57:03 djm Exp $");
+RCSID("$OpenBSD: channels.c,v 1.214 2005/03/14 11:46:56 markus Exp $");
#include "ssh.h"
#include "ssh1.h"
/* -- channel core */
+#define CHAN_RBUF 16*1024
+
/*
* Pointer to an array containing all allocated channels. The array is
* dynamically extended as needed.
* 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
{
Channel *c;
- if (id < 0 || id >= channels_alloc) {
+ if (id < 0 || (u_int)id >= channels_alloc) {
logit("channel_lookup: %d: bad id", id);
return NULL;
}
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;
channel_new(char *ctype, int type, int rfd, int wfd, int efd,
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. */
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)
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;
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++) {
static void
channel_close_fds(Channel *c)
{
- debug3("channel %d: close_fds 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);
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 %d: free: %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();
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);
void
channel_free_all(void)
{
- int i;
+ u_int i;
for (i = 0; i < channels_alloc; i++)
if (channels[i] != NULL)
void
channel_close_all(void)
{
- int i;
+ u_int i;
for (i = 0; i < channels_alloc; i++)
if (channels[i] != NULL)
void
channel_stop_listening(void)
{
- int i;
+ u_int i;
Channel *c;
for (i = 0; i < channels_alloc; i++) {
int
channel_still_open(void)
{
- int i;
+ u_int i;
Channel *c;
for (i = 0; i < channels_alloc; i++) {
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:
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");
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:
logit("channel_request_start: %d: unknown channel id", id);
return;
}
- debug2("channel %d: request %s", id, service) ;
+ 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_confirm(int id, channel_callback_fn *fn)
+channel_register_confirm(int id, channel_callback_fn *fn, void *ctx)
{
Channel *c = channel_lookup(id);
return;
}
c->confirm = fn;
+ c->confirm_ctx = ctx;
}
void
channel_register_cleanup(int id, channel_callback_fn *fn)
{
u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
+ /* check buffer limits */
+ limit = MIN(limit, (BUFFER_MAX_LEN - BUFFER_MAX_CHUNK - CHAN_RBUF));
+
if (c->istate == CHAN_INPUT_OPEN &&
limit > 0 &&
buffer_len(&c->input) < limit)
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
debug2("channel %d: only socks5 connect supported", c->self);
return -1;
}
- switch(s5_req.atyp){
+ switch (s5_req.atyp){
case SSH_SOCKS5_IPV4:
addrlen = 4;
af = AF_INET;
buffer_get(&c->input, (char *)&dest_port, 2);
dest_addr[addrlen] = '\0';
if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
- strlcpy(c->path, dest_addr, sizeof(c->path));
+ 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);
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 &&
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 */
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 &&
if (!compat20)
return;
channel_handle_efd(c, readset, writeset);
+ channel_handle_ctl(c, readset, writeset);
channel_check_window(c);
}
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) {
*/
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);
channel_output_poll(void)
{
Channel *c;
- int i;
- u_int len;
+ u_int i, len;
for (i = 0; i < channels_alloc; i++) {
c = channels[i];
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);
+ /*
+ * 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) {
logit("channel %d: rcvd big packet %d, maxpack %d",
c->remote_maxpacket = packet_get_int();
if (c->confirm) {
debug2("callback start");
- c->confirm(c->self, NULL);
+ c->confirm(c->self, c->confirm_ctx);
debug2("callback done");
}
debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
const char *host_to_connect, u_short port_to_connect, int gateway_ports)
{
Channel *c;
- int success, sock, on = 1;
+ int sock, r, success = 0, on = 1, wildcard = 0, is_client;
struct addrinfo hints, *ai, *aitop;
- const char *host;
+ const char *host, *addr;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
- success = 0;
host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
listen_addr : host_to_connect;
+ is_client = (type == SSH_CHANNEL_PORT_LISTENER);
if (host == NULL) {
error("No forward host name.");
return success;
}
+ /*
+ * 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;
}
/* 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;
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(u_short listen_port,
+channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
const char *host_to_connect, u_short port_to_connect, int gateway_ports)
{
return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
- NULL, listen_port, host_to_connect, port_to_connect, gateway_ports);
+ listen_host, listen_port, host_to_connect, port_to_connect,
+ gateway_ports);
}
/* protocol v2 remote port fwd, used by sshd */
*/
void
-channel_request_remote_forwarding(u_short listen_port,
+channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
const char *host_to_connect, u_short port_to_connect)
{
int type, success = 0;
/* Send the forward request to the remote side. */
if (compat20) {
- const char *address_to_bind = "0.0.0.0";
+ const char *address_to_bind;
+ if (listen_host == NULL)
+ address_to_bind = "localhost";
+ else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0)
+ address_to_bind = "";
+ else
+ address_to_bind = listen_host;
+
packet_start(SSH2_MSG_GLOBAL_REQUEST);
packet_put_cstring("tcpip-forward");
packet_put_char(1); /* boolean: want reply */
}
}
+/*
+ * 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
#endif
/* Initiate forwarding */
- channel_setup_local_fwd_listener(port, hostname, host_port, gateway_ports);
+ channel_setup_local_fwd_listener(NULL, port, hostname,
+ host_port, gateway_ports);
/* Free the argument string. */
xfree(hostname);
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;
}
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,
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);
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;
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 */
/*
if (sock < 0) {
if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
error("socket: %.100s", strerror(errno));
+ freeaddrinfo(aitop);
return -1;
} else {
debug("x11_create_display_inet: Socket family %d not supported",
/* 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));
close(sock);
return -1;
char *new_data;
int screen_number;
const char *cp;
- u_int32_t rand = 0;
+ u_int32_t rnd = 0;
cp = getenv("DISPLAY");
if (cp)
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;
andersk / openssh.git / blobdiff