*/
#include "includes.h"
-RCSID("$OpenBSD: channels.c,v 1.211 2004/10/29 21:47:15 djm Exp $");
+RCSID("$OpenBSD: channels.c,v 1.227 2005/10/14 02:29:37 stevesk 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.
/* Maximum number of fake X11 displays to try. */
#define MAX_DISPLAYS 1000
+/* Saved X11 local (client) display. */
+static char *x11_saved_display = NULL;
+
/* Saved X11 authentication protocol name. */
static char *x11_saved_proto = NULL;
c->force_drain = 0;
c->single_connection = 0;
c->detach_user = NULL;
+ c->detach_close = 0;
c->confirm = NULL;
c->confirm_ctx = NULL;
c->input_filter = NULL;
c->confirm_ctx = ctx;
}
void
-channel_register_cleanup(int id, channel_callback_fn *fn)
+channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
{
Channel *c = channel_lookup(id);
return;
}
c->detach_user = fn;
+ c->detach_close = do_close;
}
void
channel_cancel_cleanup(int id)
return;
}
c->detach_user = NULL;
+ c->detach_close = 0;
}
void
channel_register_filter(int id, channel_filter_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)
FD_SET(c->wfd, writeset);
} else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
- debug2("channel %d: obuf_empty delayed efd %d/(%d)",
- c->self, c->efd, buffer_len(&c->extended));
+ debug2("channel %d: obuf_empty delayed efd %d/(%d)",
+ c->self, c->efd, buffer_len(&c->extended));
else
chan_obuf_empty(c);
}
channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
{
char *p, *host;
- int len, have, i, found;
+ u_int len, have, i, found;
char username[256];
struct {
u_int8_t version;
} s5_req, s5_rsp;
u_int16_t dest_port;
u_char *p, dest_addr[255+1];
- int i, have, found, nmethods, addrlen, af;
+ u_int have, i, found, nmethods, addrlen, af;
debug2("channel %d: decode socks5", c->self);
p = buffer_ptr(&c->input);
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;
channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
{
u_char *p;
- int have, ret;
+ u_int have;
+ int ret;
have = buffer_len(&c->input);
c->delayed = 0;
int direct;
char buf[1024];
char *remote_ipaddr = get_peer_ipaddr(c->sock);
- u_short remote_port = get_peer_port(c->sock);
+ int remote_port = get_peer_port(c->sock);
direct = (strcmp(rtype, "direct-tcpip") == 0);
}
/* originator host and port */
packet_put_cstring(remote_ipaddr);
- packet_put_int(remote_port);
+ packet_put_int((u_int)remote_port);
packet_send();
} else {
packet_start(SSH_MSG_PORT_OPEN);
xfree(remote_ipaddr);
}
+static void
+channel_set_reuseaddr(int fd)
+{
+ int on = 1;
+
+ /*
+ * Set socket options.
+ * Allow local port reuse in TIME_WAIT.
+ */
+ if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
+ error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
+}
+
/*
* This socket is listening for connections to a forwarded TCP/IP 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 */
if (c == NULL)
return;
if (c->detach_user != NULL) {
- if (!chan_is_dead(c, 0))
+ if (!chan_is_dead(c, c->detach_close))
return;
debug2("channel %d: gc: notify user", c->self);
c->detach_user(c->self, NULL);
* hack for extended data: delay EOF if EFD still in use.
*/
if (CHANNEL_EFD_INPUT_ACTIVE(c))
- debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
- c->self, c->efd, buffer_len(&c->extended));
+ debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
+ c->self, c->efd, buffer_len(&c->extended));
else
chan_ibuf_empty(c);
}
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, wildcard = 0, is_client;
struct addrinfo hints, *ai, *aitop;
- const char *host;
+ const char *host, *addr;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
- success = 0;
host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
listen_addr : host_to_connect;
+ is_client = (type == SSH_CHANNEL_PORT_LISTENER);
if (host == NULL) {
error("No forward host name.");
- return success;
+ return 0;
}
if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
error("Forward host name too long.");
- return success;
+ return 0;
}
+ /*
+ * Determine whether or not a port forward listens to loopback,
+ * specified address or wildcard. On the client, a specified bind
+ * address will always override gateway_ports. On the server, a
+ * gateway_ports of 1 (``yes'') will override the client's
+ * specification and force a wildcard bind, whereas a value of 2
+ * (``clientspecified'') will bind to whatever address the client
+ * asked for.
+ *
+ * Special-case listen_addrs are:
+ *
+ * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
+ * "" (empty string), "*" -> wildcard v4/v6
+ * "localhost" -> loopback v4/v6
+ */
+ addr = NULL;
+ if (listen_addr == NULL) {
+ /* No address specified: default to gateway_ports setting */
+ if (gateway_ports)
+ wildcard = 1;
+ } else if (gateway_ports || is_client) {
+ if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
+ strcmp(listen_addr, "0.0.0.0") == 0) ||
+ *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
+ (!is_client && gateway_ports == 1))
+ wildcard = 1;
+ else if (strcmp(listen_addr, "localhost") != 0)
+ addr = listen_addr;
+ }
+
+ debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
+ type, wildcard, (addr == NULL) ? "NULL" : addr);
+
/*
* getaddrinfo returns a loopback address if the hostname is
* set to NULL and hints.ai_flags is not AI_PASSIVE
*/
memset(&hints, 0, sizeof(hints));
hints.ai_family = IPv4or6;
- hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
+ hints.ai_flags = wildcard ? AI_PASSIVE : 0;
hints.ai_socktype = SOCK_STREAM;
snprintf(strport, sizeof strport, "%d", listen_port);
- if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
- packet_disconnect("getaddrinfo: fatal error");
+ if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
+ if (addr == NULL) {
+ /* This really shouldn't happen */
+ packet_disconnect("getaddrinfo: fatal error: %s",
+ gai_strerror(r));
+ } else {
+ error("channel_setup_fwd_listener: "
+ "getaddrinfo(%.64s): %s", addr, gai_strerror(r));
+ }
+ return 0;
+ }
for (ai = aitop; ai; ai = ai->ai_next) {
if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
verbose("socket: %.100s", strerror(errno));
continue;
}
- /*
- * Set socket options.
- * Allow local port reuse in TIME_WAIT.
- */
- if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on,
- sizeof(on)) == -1)
- error("setsockopt SO_REUSEADDR: %s", strerror(errno));
+
+ channel_set_reuseaddr(sock);
debug("Local forwarding listening on %s port %s.", ntop, strport);
u_int i;
int found = 0;
- for(i = 0; i < channels_alloc; i++) {
+ for (i = 0; i < channels_alloc; i++) {
Channel *c = channels[i];
if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
/* 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 */
* local side.
*/
void
-channel_request_rforward_cancel(u_short port)
+channel_request_rforward_cancel(const char *host, u_short port)
{
int i;
- const char *address_to_bind = "0.0.0.0";
if (!compat20)
return;
packet_start(SSH2_MSG_GLOBAL_REQUEST);
packet_put_cstring("cancel-tcpip-forward");
packet_put_char(0);
- packet_put_cstring(address_to_bind);
+ packet_put_cstring(host == NULL ? "" : host);
packet_put_int(port);
packet_send();
permitted_opens[i].listen_port = 0;
permitted_opens[i].port_to_connect = 0;
- free(permitted_opens[i].host_to_connect);
+ xfree(permitted_opens[i].host_to_connect);
permitted_opens[i].host_to_connect = NULL;
}
#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);
struct winsize ws;
for (i = 0; i < channels_alloc; i++) {
- if (channels[i] == NULL || !channels[i]->client_tty ||
+ if (channels[i] == NULL || !channels[i]->client_tty ||
channels[i]->type != SSH_CHANNEL_OPEN)
continue;
if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
*/
int
x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
- int single_connection, u_int *display_numberp)
+ int single_connection, u_int *display_numberp, int **chanids)
{
Channel *nc = NULL;
int display_number, sock;
char strport[NI_MAXSERV];
int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
+ if (chanids == NULL)
+ return -1;
+
for (display_number = x11_display_offset;
display_number < MAX_DISPLAYS;
display_number++) {
error("setsockopt IPV6_V6ONLY: %.100s", strerror(errno));
}
#endif
+ channel_set_reuseaddr(sock);
if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
debug2("bind port %d: %.100s", port, strerror(errno));
close(sock);
}
/* Allocate a channel for each socket. */
+ *chanids = xmalloc(sizeof(**chanids) * (num_socks + 1));
for (n = 0; n < num_socks; n++) {
sock = socks[n];
nc = channel_new("x11 listener",
CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
0, "X11 inet listener", 1);
nc->single_connection = single_connection;
+ (*chanids)[n] = nc->self;
}
+ (*chanids)[n] = -1;
/* Return the display number for the DISPLAY environment variable. */
*display_numberp = display_number;
* This should be called in the client only.
*/
void
-x11_request_forwarding_with_spoofing(int client_session_id,
+x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
const char *proto, const char *data)
{
u_int data_len = (u_int) strlen(data) / 2;
- u_int i, value, len;
+ u_int i, value;
char *new_data;
int screen_number;
const char *cp;
u_int32_t rnd = 0;
- cp = getenv("DISPLAY");
- if (cp)
- cp = strchr(cp, ':');
+ if (x11_saved_display == NULL)
+ x11_saved_display = xstrdup(disp);
+ else if (strcmp(disp, x11_saved_display) != 0) {
+ error("x11_request_forwarding_with_spoofing: different "
+ "$DISPLAY already forwarded");
+ return;
+ }
+
+ cp = disp;
+ if (disp)
+ cp = strchr(disp, ':');
if (cp)
cp = strchr(cp, '.');
if (cp)
else
screen_number = 0;
- /* Save protocol name. */
- x11_saved_proto = xstrdup(proto);
-
- /*
- * Extract real authentication data and generate fake data of the
- * same length.
- */
- x11_saved_data = xmalloc(data_len);
- x11_fake_data = xmalloc(data_len);
- for (i = 0; i < data_len; i++) {
- if (sscanf(data + 2 * i, "%2x", &value) != 1)
- fatal("x11_request_forwarding: bad authentication data: %.100s", data);
- if (i % 4 == 0)
- rnd = arc4random();
- x11_saved_data[i] = value;
- x11_fake_data[i] = rnd & 0xff;
- rnd >>= 8;
- }
- x11_saved_data_len = data_len;
- x11_fake_data_len = data_len;
+ if (x11_saved_proto == NULL) {
+ /* Save protocol name. */
+ x11_saved_proto = xstrdup(proto);
+ /*
+ * Extract real authentication data and generate fake data
+ * of the same length.
+ */
+ x11_saved_data = xmalloc(data_len);
+ x11_fake_data = xmalloc(data_len);
+ for (i = 0; i < data_len; i++) {
+ if (sscanf(data + 2 * i, "%2x", &value) != 1)
+ fatal("x11_request_forwarding: bad "
+ "authentication data: %.100s", data);
+ if (i % 4 == 0)
+ rnd = arc4random();
+ x11_saved_data[i] = value;
+ x11_fake_data[i] = rnd & 0xff;
+ rnd >>= 8;
+ }
+ x11_saved_data_len = data_len;
+ x11_fake_data_len = data_len;
+ }
/* Convert the fake data into hex. */
- len = 2 * data_len + 1;
- new_data = xmalloc(len);
- for (i = 0; i < data_len; i++)
- snprintf(new_data + 2 * i, len - 2 * i,
- "%02x", (u_char) x11_fake_data[i]);
+ new_data = tohex(x11_fake_data, data_len);
/* Send the request packet. */
if (compat20) {
andersk / openssh.git / blobdiff