*/
#include "includes.h"
-RCSID("$Id$");
+RCSID("$OpenBSD: ssh.c,v 1.56 2000/06/20 01:39:44 markus Exp $");
+
+#include <openssl/evp.h>
+#include <openssl/dsa.h>
+#include <openssl/rsa.h>
#include "xmalloc.h"
#include "ssh.h"
#include "readconf.h"
#include "uidswap.h"
+#include "ssh2.h"
+#include "compat.h"
+#include "channels.h"
+#include "key.h"
+#include "authfile.h"
+
#ifdef HAVE___PROGNAME
extern char *__progname;
#else /* HAVE___PROGNAME */
-const char *__progname = "ssh";
+static const char *__progname = "ssh";
#endif /* HAVE___PROGNAME */
/* Flag indicating whether IPv4 or IPv6. This can be set on the command line.
/* Flag indicating whether debug mode is on. This can be set on the command line. */
int debug_flag = 0;
+/* Flag indicating whether a tty should be allocated */
int tty_flag = 0;
+/* don't exec a shell */
+int no_shell_flag = 0;
+int no_tty_flag = 0;
+
/*
* Flag indicating that nothing should be read from stdin. This can be set
* on the command line.
/* Original real UID. */
uid_t original_real_uid;
+/* command to be executed */
+Buffer command;
+
/* Prints a help message to the user. This function never returns. */
void
fprintf(stderr, "Options:\n");
fprintf(stderr, " -l user Log in using this user name.\n");
fprintf(stderr, " -n Redirect input from /dev/null.\n");
+ fprintf(stderr, " -A Enable authentication agent forwarding.\n");
fprintf(stderr, " -a Disable authentication agent forwarding.\n");
#ifdef AFS
fprintf(stderr, " -k Disable Kerberos ticket and AFS token forwarding.\n");
#endif /* AFS */
+ fprintf(stderr, " -X Enable X11 connection forwarding.\n");
fprintf(stderr, " -x Disable X11 connection forwarding.\n");
fprintf(stderr, " -i file Identity for RSA authentication (default: ~/.ssh/identity).\n");
fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n");
+ fprintf(stderr, " -T Do not allocate a tty.\n");
fprintf(stderr, " -v Verbose; display verbose debugging messages.\n");
fprintf(stderr, " -V Display version number only.\n");
fprintf(stderr, " -P Don't allocate a privileged port.\n");
fprintf(stderr, " These cause %s to listen for connections on a port, and\n", av0);
fprintf(stderr, " forward them to the other side by connecting to host:port.\n");
fprintf(stderr, " -C Enable compression.\n");
+ fprintf(stderr, " -N Do not execute a shell or command.\n");
fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n");
fprintf(stderr, " -4 Use IPv4 only.\n");
fprintf(stderr, " -6 Use IPv6 only.\n");
+ fprintf(stderr, " -2 Force protocol version 2.\n");
fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n");
exit(1);
}
exit(1);
}
+int ssh_session(void);
+int ssh_session2(void);
+
/*
* Main program for the ssh client.
*/
int
main(int ac, char **av)
{
- int i, opt, optind, type, exit_status, ok, authfd;
+ int i, opt, optind, exit_status, ok;
u_short fwd_port, fwd_host_port;
char *optarg, *cp, buf[256];
- Buffer command;
- struct winsize ws;
struct stat st;
struct passwd *pw, pwcopy;
- int interactive = 0, dummy;
+ int dummy;
uid_t original_effective_uid;
- int plen;
/*
* Save the original real uid. It will be needed later (uid-swapping
/* Save our own name. */
av0 = av[0];
-#ifdef SOCKS
- SOCKSinit(av0);
-#endif /* SOCKS */
-
/* Initialize option structure to indicate that no values have been set. */
initialize_options(&options);
if (host)
break;
if ((cp = strchr(av[optind], '@'))) {
- if(cp == av[optind])
- usage();
+ if(cp == av[optind])
+ usage();
options.user = av[optind];
*cp = '\0';
host = ++cp;
optarg = NULL;
}
switch (opt) {
+ case '2':
+ options.protocol = SSH_PROTO_2;
+ break;
case '4':
IPv4or6 = AF_INET;
break;
-
case '6':
IPv4or6 = AF_INET6;
break;
-
case 'n':
stdin_null_flag = 1;
break;
-
case 'f':
fork_after_authentication_flag = 1;
stdin_null_flag = 1;
break;
-
case 'x':
options.forward_x11 = 0;
break;
-
case 'X':
options.forward_x11 = 1;
break;
-
case 'g':
options.gateway_ports = 1;
break;
-
case 'P':
options.use_privileged_port = 0;
break;
-
case 'a':
options.forward_agent = 0;
break;
+ case 'A':
+ options.forward_agent = 1;
+ break;
#ifdef AFS
case 'k':
options.kerberos_tgt_passing = 0;
options.identity_files[options.num_identity_files++] =
xstrdup(optarg);
break;
-
case 't':
tty_flag = 1;
break;
-
case 'v':
case 'V':
- fprintf(stderr, "SSH Version %s, protocol version %d.%d.\n",
- SSH_VERSION, PROTOCOL_MAJOR, PROTOCOL_MINOR);
-#ifndef RSAREF
- fprintf(stderr, "Compiled with SSL.\n");
-#else
- fprintf(stderr, "Compiled with SSL (RSAref version).\n");
-#endif
+ fprintf(stderr, "SSH Version %s, protocol versions %d.%d/%d.%d.\n",
+ SSH_VERSION,
+ PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
+ PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2);
+ fprintf(stderr, "Compiled with SSL (0x%8.8lx).\n", SSLeay());
if (opt == 'V')
exit(0);
debug_flag = 1;
options.log_level = SYSLOG_LEVEL_DEBUG;
break;
-
case 'q':
options.log_level = SYSLOG_LEVEL_QUIET;
break;
-
case 'e':
if (optarg[0] == '^' && optarg[2] == 0 &&
(unsigned char) optarg[1] >= 64 && (unsigned char) optarg[1] < 128)
exit(1);
}
break;
-
case 'c':
- options.cipher = cipher_number(optarg);
- if (options.cipher == -1) {
- fprintf(stderr, "Unknown cipher type '%s'\n", optarg);
- exit(1);
+ if (ciphers_valid(optarg)) {
+ /* SSH2 only */
+ options.ciphers = xstrdup(optarg);
+ options.cipher = SSH_CIPHER_ILLEGAL;
+ } else {
+ /* SSH1 only */
+ options.cipher = cipher_number(optarg);
+ if (options.cipher == -1) {
+ fprintf(stderr, "Unknown cipher type '%s'\n", optarg);
+ exit(1);
+ }
}
break;
-
case 'p':
options.port = atoi(optarg);
break;
-
case 'l':
options.user = optarg;
break;
-
case 'R':
if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
&fwd_host_port) != 3 &&
}
add_remote_forward(&options, fwd_port, buf, fwd_host_port);
break;
-
case 'L':
if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
&fwd_host_port) != 3 &&
}
add_local_forward(&options, fwd_port, buf, fwd_host_port);
break;
-
case 'C':
options.compression = 1;
break;
-
+ case 'N':
+ no_shell_flag = 1;
+ no_tty_flag = 1;
+ break;
+ case 'T':
+ no_tty_flag = 1;
+ break;
case 'o':
dummy = 1;
if (process_config_line(&options, host ? host : "", optarg,
"command-line", 0, &dummy) != 0)
exit(1);
break;
-
default:
usage();
}
if (!host)
usage();
- /* check if RSA support exists */
- if (rsa_alive() == 0) {
- fprintf(stderr,
- "%s: no RSA support in libssl and libcrypto. See ssl(8).\n",
- __progname);
- exit(1);
- }
/* Initialize the command to execute on remote host. */
buffer_init(&command);
+ SSLeay_add_all_algorithms();
+
/*
* Save the command to execute on the remote host in a buffer. There
* is no limit on the length of the command, except by the maximum
fprintf(stderr, "Pseudo-terminal will not be allocated because stdin is not a terminal.\n");
tty_flag = 0;
}
+ /* force */
+ if (no_tty_flag)
+ tty_flag = 0;
+
/* Get user data. */
pw = getpwuid(original_real_uid);
if (!pw) {
/* reinit */
log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 0);
+ /* check if RSA support exists */
+ if ((options.protocol & SSH_PROTO_1) &&
+ rsa_alive() == 0) {
+ log("%s: no RSA support in libssl and libcrypto. See ssl(8).",
+ __progname);
+ log("Disabling protocol version 1");
+ options.protocol &= ~ (SSH_PROTO_1|SSH_PROTO_1_PREFERRED);
+ }
+ if (! options.protocol & (SSH_PROTO_1|SSH_PROTO_2)) {
+ fprintf(stderr, "%s: No protocol version available.\n",
+ __progname);
+ exit(1);
+ }
+
if (options.user == NULL)
options.user = xstrdup(pw->pw_name);
struct addrinfo *ai = NULL;
int errgai;
memset(&hints, 0, sizeof(hints));
- hints.ai_family = AF_UNSPEC;
+ hints.ai_family = IPv4or6;
hints.ai_flags = AI_CANONNAME;
hints.ai_socktype = SOCK_STREAM;
errgai = getaddrinfo(host, NULL, &hints, &ai);
* authentication. This must be done before releasing extra
* privileges, because the file is only readable by root.
*/
- if (ok) {
+ if (ok && (options.protocol & SSH_PROTO_1)) {
+ Key k;
host_private_key = RSA_new();
- if (load_private_key(HOST_KEY_FILE, "", host_private_key, NULL))
+ k.type = KEY_RSA;
+ k.rsa = host_private_key;
+ if (load_private_key(HOST_KEY_FILE, "", &k, NULL))
host_private_key_loaded = 1;
}
/*
exit(1);
}
/* Expand ~ in options.identity_files. */
+ /* XXX mem-leaks */
for (i = 0; i < options.num_identity_files; i++)
options.identity_files[i] =
tilde_expand_filename(options.identity_files[i], original_real_uid);
-
+ for (i = 0; i < options.num_identity_files2; i++)
+ options.identity_files2[i] =
+ tilde_expand_filename(options.identity_files2[i], original_real_uid);
/* Expand ~ in known host file names. */
options.system_hostfile = tilde_expand_filename(options.system_hostfile,
- original_real_uid);
+ original_real_uid);
options.user_hostfile = tilde_expand_filename(options.user_hostfile,
- original_real_uid);
+ original_real_uid);
+ options.system_hostfile2 = tilde_expand_filename(options.system_hostfile2,
+ original_real_uid);
+ options.user_hostfile2 = tilde_expand_filename(options.user_hostfile2,
+ original_real_uid);
/* Log into the remote system. This never returns if the login fails. */
ssh_login(host_private_key_loaded, host_private_key,
if (host_private_key_loaded)
RSA_free(host_private_key); /* Destroys contents safely */
- /* Close connection cleanly after attack. */
- cipher_attack_detected = packet_disconnect;
+ exit_status = compat20 ? ssh_session2() : ssh_session();
+ packet_close();
+ return exit_status;
+}
+
+void
+x11_get_proto(char *proto, int proto_len, char *data, int data_len)
+{
+ char line[512];
+ FILE *f;
+ int got_data = 0, i;
+
+ if (options.xauth_location) {
+ /* Try to get Xauthority information for the display. */
+ snprintf(line, sizeof line, "%.100s list %.200s 2>/dev/null",
+ options.xauth_location, getenv("DISPLAY"));
+ f = popen(line, "r");
+ if (f && fgets(line, sizeof(line), f) &&
+ sscanf(line, "%*s %s %s", proto, data) == 2)
+ got_data = 1;
+ if (f)
+ pclose(f);
+ }
+ /*
+ * If we didn't get authentication data, just make up some
+ * data. The forwarding code will check the validity of the
+ * response anyway, and substitute this data. The X11
+ * server, however, will ignore this fake data and use
+ * whatever authentication mechanisms it was using otherwise
+ * for the local connection.
+ */
+ if (!got_data) {
+ u_int32_t rand = 0;
+
+ strlcpy(proto, "MIT-MAGIC-COOKIE-1", proto_len);
+ for (i = 0; i < 16; i++) {
+ if (i % 4 == 0)
+ rand = arc4random();
+ snprintf(data + 2 * i, data_len - 2 * i, "%02x", rand & 0xff);
+ rand >>= 8;
+ }
+ }
+}
+
+int
+ssh_session(void)
+{
+ int type;
+ int i;
+ int plen;
+ int interactive = 0;
+ int have_tty = 0;
+ struct winsize ws;
+ int authfd;
+ char *cp;
/* Enable compression if requested. */
if (options.compression) {
/* Read response from the server. */
type = packet_read(&plen);
- if (type == SSH_SMSG_SUCCESS)
+ if (type == SSH_SMSG_SUCCESS) {
interactive = 1;
- else if (type == SSH_SMSG_FAILURE)
+ have_tty = 1;
+ } else if (type == SSH_SMSG_FAILURE)
log("Warning: Remote host failed or refused to allocate a pseudo tty.");
else
packet_disconnect("Protocol error waiting for pty request response.");
}
/* Request X11 forwarding if enabled and DISPLAY is set. */
if (options.forward_x11 && getenv("DISPLAY") != NULL) {
- char line[512], proto[512], data[512];
- FILE *f;
- int forwarded = 0, got_data = 0, i;
-
-#ifdef XAUTH_PATH
- /* Try to get Xauthority information for the display. */
- snprintf(line, sizeof line, "%.100s list %.200s 2>/dev/null",
- XAUTH_PATH, getenv("DISPLAY"));
- f = popen(line, "r");
- if (f && fgets(line, sizeof(line), f) &&
- sscanf(line, "%*s %s %s", proto, data) == 2)
- got_data = 1;
- if (f)
- pclose(f);
-#endif /* XAUTH_PATH */
- /*
- * If we didn't get authentication data, just make up some
- * data. The forwarding code will check the validity of the
- * response anyway, and substitute this data. The X11
- * server, however, will ignore this fake data and use
- * whatever authentication mechanisms it was using otherwise
- * for the local connection.
- */
- if (!got_data) {
- u_int32_t rand = 0;
-
- strlcpy(proto, "MIT-MAGIC-COOKIE-1", sizeof proto);
- for (i = 0; i < 16; i++) {
- if (i % 4 == 0)
- rand = arc4random();
- snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", rand & 0xff);
- rand >>= 8;
- }
- }
- /*
- * Got local authentication reasonable information. Request
- * forwarding with authentication spoofing.
- */
+ char proto[512], data[512];
+ /* Get reasonable local authentication information. */
+ x11_get_proto(proto, sizeof proto, data, sizeof data);
+ /* Request forwarding with authentication spoofing. */
debug("Requesting X11 forwarding with authentication spoofing.");
- x11_request_forwarding_with_spoofing(proto, data);
+ x11_request_forwarding_with_spoofing(0, proto, data);
/* Read response from the server. */
type = packet_read(&plen);
if (type == SSH_SMSG_SUCCESS) {
- forwarded = 1;
interactive = 1;
- } else if (type == SSH_SMSG_FAILURE)
+ } else if (type == SSH_SMSG_FAILURE) {
log("Warning: Remote host denied X11 forwarding.");
- else
+ } else {
packet_disconnect("Protocol error waiting for X11 forwarding");
+ }
}
/* Tell the packet module whether this is an interactive session. */
packet_set_interactive(interactive, options.keepalives);
options.local_forwards[i].host,
options.local_forwards[i].host_port);
channel_request_local_forwarding(options.local_forwards[i].port,
- options.local_forwards[i].host,
+ options.local_forwards[i].host,
options.local_forwards[i].host_port,
options.gateway_ports);
}
options.remote_forwards[i].host_port);
channel_request_remote_forwarding(options.remote_forwards[i].port,
options.remote_forwards[i].host,
- options.remote_forwards[i].host_port);
+ options.remote_forwards[i].host_port);
}
/* If requested, let ssh continue in the background. */
- if (fork_after_authentication_flag)
+ if (fork_after_authentication_flag)
if (daemon(1, 1) < 0)
fatal("daemon() failed: %.200s", strerror(errno));
}
/* Enter the interactive session. */
- exit_status = client_loop(tty_flag, tty_flag ? options.escape_char : -1);
+ return client_loop(have_tty, tty_flag ? options.escape_char : -1);
+}
- /* Close the connection to the remote host. */
- packet_close();
+void
+init_local_fwd(void)
+{
+ int i;
+ /* Initiate local TCP/IP port forwardings. */
+ for (i = 0; i < options.num_local_forwards; i++) {
+ debug("Connections to local port %d forwarded to remote address %.200s:%d",
+ options.local_forwards[i].port,
+ options.local_forwards[i].host,
+ options.local_forwards[i].host_port);
+ channel_request_local_forwarding(options.local_forwards[i].port,
+ options.local_forwards[i].host,
+ options.local_forwards[i].host_port,
+ options.gateway_ports);
+ }
+}
+
+extern void client_set_session_ident(int id);
+
+void
+client_init(int id, void *arg)
+{
+ int len;
+ debug("client_init id %d arg %d", id, (int)arg);
+
+ if (no_shell_flag)
+ goto done;
+
+ if (tty_flag) {
+ struct winsize ws;
+ char *cp;
+ cp = getenv("TERM");
+ if (!cp)
+ cp = "";
+ /* Store window size in the packet. */
+ if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
+ memset(&ws, 0, sizeof(ws));
+
+ channel_request_start(id, "pty-req", 0);
+ packet_put_cstring(cp);
+ 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_put_cstring(""); /* XXX: encode terminal modes */
+ packet_send();
+ /* XXX wait for reply */
+ }
+ if (options.forward_x11 &&
+ getenv("DISPLAY") != NULL) {
+ char proto[512], data[512];
+ /* Get reasonable local authentication information. */
+ x11_get_proto(proto, sizeof proto, data, sizeof data);
+ /* Request forwarding with authentication spoofing. */
+ debug("Requesting X11 forwarding with authentication spoofing.");
+ x11_request_forwarding_with_spoofing(id, proto, data);
+ /* XXX wait for reply */
+ }
+
+ len = buffer_len(&command);
+ if (len > 0) {
+ if (len > 900)
+ len = 900;
+ debug("Sending command: %.*s", len, buffer_ptr(&command));
+ channel_request_start(id, "exec", 0);
+ packet_put_string(buffer_ptr(&command), len);
+ packet_send();
+ } else {
+ channel_request(id, "shell", 0);
+ }
+ /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */
+done:
+ /* register different callback, etc. XXX */
+ client_set_session_ident(id);
+}
+
+int
+ssh_session2(void)
+{
+ int window, packetmax, id;
+ int in = dup(STDIN_FILENO);
+ int out = dup(STDOUT_FILENO);
+ int err = dup(STDERR_FILENO);
+
+ if (in < 0 || out < 0 || err < 0)
+ fatal("dump in/out/err failed");
+
+ /* should be pre-session */
+ init_local_fwd();
+
+ window = 32*1024;
+ if (tty_flag) {
+ packetmax = window/8;
+ } else {
+ window *= 2;
+ packetmax = window/2;
+ }
+
+ id = channel_new(
+ "session", SSH_CHANNEL_OPENING, in, out, err,
+ window, packetmax, CHAN_EXTENDED_WRITE, xstrdup("client-session"));
+
+
+ channel_open(id);
+ channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, client_init, (void *)0);
- /* Exit with the status returned by the program on the remote side. */
- exit(exit_status);
+ return client_loop(tty_flag, tty_flag ? options.escape_char : -1);
}
andersk / openssh.git / blobdiff