+
+ logevent("Encrypted session key");
+
+ {
+ int cipher_chosen = 0, warn = 0;
+ char *cipher_string = NULL;
+ int i;
+ for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
+ int next_cipher = ssh->cfg.ssh_cipherlist[i];
+ if (next_cipher == CIPHER_WARN) {
+ /* If/when we choose a cipher, warn about it */
+ warn = 1;
+ } else if (next_cipher == CIPHER_AES) {
+ /* XXX Probably don't need to mention this. */
+ logevent("AES not supported in SSH1, skipping");
+ } else {
+ switch (next_cipher) {
+ case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
+ cipher_string = "3DES"; break;
+ case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
+ cipher_string = "Blowfish"; break;
+ case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
+ cipher_string = "single-DES"; break;
+ }
+ if (s->supported_ciphers_mask & (1 << s->cipher_type))
+ cipher_chosen = 1;
+ }
+ }
+ if (!cipher_chosen) {
+ if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
+ bombout(("Server violates SSH 1 protocol by not "
+ "supporting 3DES encryption"));
+ else
+ /* shouldn't happen */
+ bombout(("No supported ciphers found"));
+ crStop(0);
+ }
+
+ /* Warn about chosen cipher if necessary. */
+ if (warn)
+ askcipher(ssh->frontend, cipher_string, 0);
+ }
+
+ switch (s->cipher_type) {
+ case SSH_CIPHER_3DES:
+ logevent("Using 3DES encryption");
+ break;
+ case SSH_CIPHER_DES:
+ logevent("Using single-DES encryption");
+ break;
+ case SSH_CIPHER_BLOWFISH:
+ logevent("Using Blowfish encryption");
+ break;
+ }
+
+ send_packet(ssh, SSH1_CMSG_SESSION_KEY,
+ PKT_CHAR, s->cipher_type,
+ PKT_DATA, cookie, 8,
+ PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
+ PKT_DATA, s->rsabuf, s->len,
+ PKT_INT, ssh->v1_local_protoflags, PKT_END);
+
+ logevent("Trying to enable encryption...");
+
+ sfree(s->rsabuf);
+
+ ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
+ s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
+ &ssh_3des);
+ ssh->v1_cipher_ctx = ssh->cipher->make_context();
+ ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
+ logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
+
+ ssh->crcda_ctx = crcda_make_context();
+ logevent("Installing CRC compensation attack detector");
+
+ if (servkey.modulus) {
+ sfree(servkey.modulus);
+ servkey.modulus = NULL;
+ }
+ if (servkey.exponent) {
+ sfree(servkey.exponent);
+ servkey.exponent = NULL;
+ }
+ if (hostkey.modulus) {
+ sfree(hostkey.modulus);
+ hostkey.modulus = NULL;
+ }
+ if (hostkey.exponent) {
+ sfree(hostkey.exponent);
+ hostkey.exponent = NULL;
+ }
+ crWaitUntil(pktin);
+
+ if (pktin->type != SSH1_SMSG_SUCCESS) {
+ bombout(("Encryption not successfully enabled"));
+ crStop(0);
+ }
+
+ logevent("Successfully started encryption");
+
+ fflush(stdout);
+ {
+ if (!*ssh->cfg.username) {
+ if (ssh_get_line && !ssh_getline_pw_only) {
+ if (!ssh_get_line("login as: ",
+ s->username, sizeof(s->username), FALSE)) {
+ /*
+ * get_line failed to get a username.
+ * Terminate.
+ */
+ logevent("No username provided. Abandoning session.");
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ crStop(1);
+ }
+ } else {
+ int ret; /* need not be kept over crReturn */
+ c_write_str(ssh, "login as: ");
+ ssh->send_ok = 1;
+
+ setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
+ do {
+ crWaitUntil(!pktin);
+ ret = process_userpass_input(ssh, in, inlen);
+ } while (ret == 0);
+ if (ret < 0)
+ cleanup_exit(0);
+ c_write_str(ssh, "\r\n");
+ }
+ } else {
+ strncpy(s->username, ssh->cfg.username, sizeof(s->username));
+ s->username[sizeof(s->username)-1] = '\0';
+ }
+
+ send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
+ {
+ char userlog[22 + sizeof(s->username)];
+ sprintf(userlog, "Sent username \"%s\"", s->username);
+ logevent(userlog);
+ if (flags & FLAG_INTERACTIVE &&
+ (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
+ strcat(userlog, "\r\n");
+ c_write_str(ssh, userlog);
+ }
+ }
+ }
+
+ crWaitUntil(pktin);
+
+ if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
+ /* We must not attempt PK auth. Pretend we've already tried it. */
+ s->tried_publickey = s->tried_agent = 1;
+ } else {
+ s->tried_publickey = s->tried_agent = 0;
+ }
+ s->tis_auth_refused = s->ccard_auth_refused = 0;
+ /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
+ if (!filename_is_null(ssh->cfg.keyfile)) {
+ if (!rsakey_pubblob(&ssh->cfg.keyfile,
+ &s->publickey_blob, &s->publickey_bloblen, NULL))
+ s->publickey_blob = NULL;
+ } else
+ s->publickey_blob = NULL;
+
+ while (pktin->type == SSH1_SMSG_FAILURE) {
+ s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
+
+ if (agent_exists() && !s->tried_agent) {
+ /*
+ * Attempt RSA authentication using Pageant.
+ */
+ void *r;
+
+ s->authed = FALSE;
+ s->tried_agent = 1;
+ logevent("Pageant is running. Requesting keys.");
+
+ /* Request the keys held by the agent. */
+ PUT_32BIT(s->request, 1);
+ s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
+ if (!agent_query(s->request, 5, &r, &s->responselen,
+ ssh_agent_callback, ssh)) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while waiting"
+ " for agent response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ r = ssh->agent_response;
+ s->responselen = ssh->agent_response_len;
+ }
+ s->response = (unsigned char *) r;
+ if (s->response && s->responselen >= 5 &&
+ s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
+ s->p = s->response + 5;
+ s->nkeys = GET_32BIT(s->p);
+ s->p += 4;
+ {
+ char buf[64];
+ sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
+ logevent(buf);
+ }
+ for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
+ {
+ char buf[64];
+ sprintf(buf, "Trying Pageant key #%d", s->keyi);
+ logevent(buf);
+ }
+ if (s->publickey_blob &&
+ !memcmp(s->p, s->publickey_blob,
+ s->publickey_bloblen)) {
+ logevent("This key matches configured key file");
+ s->tried_publickey = 1;
+ }
+ s->p += 4;
+ {
+ int n, ok = FALSE;
+ do { /* do while (0) to make breaking easy */
+ n = ssh1_read_bignum
+ (s->p, s->responselen-(s->p-s->response),
+ &s->key.exponent);
+ if (n < 0)
+ break;
+ s->p += n;
+ n = ssh1_read_bignum
+ (s->p, s->responselen-(s->p-s->response),
+ &s->key.modulus);
+ if (n < 0)
+ break;
+ s->p += n;
+ if (s->responselen - (s->p-s->response) < 4)
+ break;
+ s->commentlen = GET_32BIT(s->p);
+ s->p += 4;
+ if (s->responselen - (s->p-s->response) <
+ s->commentlen)
+ break;
+ s->commentp = (char *)s->p;
+ s->p += s->commentlen;
+ ok = TRUE;
+ } while (0);
+ if (!ok) {
+ logevent("Pageant key list packet was truncated");
+ break;
+ }
+ }
+ send_packet(ssh, SSH1_CMSG_AUTH_RSA,
+ PKT_BIGNUM, s->key.modulus, PKT_END);
+ crWaitUntil(pktin);
+ if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
+ logevent("Key refused");
+ continue;
+ }
+ logevent("Received RSA challenge");
+ if ((s->challenge = ssh1_pkt_getmp(pktin)) == NULL) {
+ bombout(("Server's RSA challenge was badly formatted"));
+ crStop(0);
+ }
+
+ {
+ char *agentreq, *q, *ret;
+ void *vret;
+ int len, retlen;
+ len = 1 + 4; /* message type, bit count */
+ len += ssh1_bignum_length(s->key.exponent);
+ len += ssh1_bignum_length(s->key.modulus);
+ len += ssh1_bignum_length(s->challenge);
+ len += 16; /* session id */
+ len += 4; /* response format */
+ agentreq = snewn(4 + len, char);
+ PUT_32BIT(agentreq, len);
+ q = agentreq + 4;
+ *q++ = SSH1_AGENTC_RSA_CHALLENGE;
+ PUT_32BIT(q, bignum_bitcount(s->key.modulus));
+ q += 4;
+ q += ssh1_write_bignum(q, s->key.exponent);
+ q += ssh1_write_bignum(q, s->key.modulus);
+ q += ssh1_write_bignum(q, s->challenge);
+ memcpy(q, s->session_id, 16);
+ q += 16;
+ PUT_32BIT(q, 1); /* response format */
+ if (!agent_query(agentreq, len + 4, &vret, &retlen,
+ ssh_agent_callback, ssh)) {
+ sfree(agentreq);
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server"
+ " while waiting for agent"
+ " response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ vret = ssh->agent_response;
+ retlen = ssh->agent_response_len;
+ } else
+ sfree(agentreq);
+ ret = vret;
+ if (ret) {
+ if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
+ logevent("Sending Pageant's response");
+ send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
+ PKT_DATA, ret + 5, 16,
+ PKT_END);
+ sfree(ret);
+ crWaitUntil(pktin);
+ if (pktin->type == SSH1_SMSG_SUCCESS) {
+ logevent
+ ("Pageant's response accepted");
+ if (flags & FLAG_VERBOSE) {
+ c_write_str(ssh, "Authenticated using"
+ " RSA key \"");
+ c_write(ssh, s->commentp,
+ s->commentlen);
+ c_write_str(ssh, "\" from agent\r\n");
+ }
+ s->authed = TRUE;
+ } else
+ logevent
+ ("Pageant's response not accepted");
+ } else {
+ logevent
+ ("Pageant failed to answer challenge");
+ sfree(ret);
+ }
+ } else {
+ logevent("No reply received from Pageant");
+ }
+ }
+ freebn(s->key.exponent);
+ freebn(s->key.modulus);
+ freebn(s->challenge);
+ if (s->authed)
+ break;
+ }
+ sfree(s->response);
+ }
+ if (s->authed)
+ break;
+ }
+ if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
+ s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
+
+ if (ssh->cfg.try_tis_auth &&
+ (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
+ !s->tis_auth_refused) {
+ s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
+ logevent("Requested TIS authentication");
+ send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
+ crWaitUntil(pktin);
+ if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
+ logevent("TIS authentication declined");
+ if (flags & FLAG_INTERACTIVE)
+ c_write_str(ssh, "TIS authentication refused.\r\n");
+ s->tis_auth_refused = 1;
+ continue;
+ } else {
+ char *challenge;
+ int challengelen;
+
+ ssh_pkt_getstring(pktin, &challenge, &challengelen);
+ if (!challenge) {
+ bombout(("TIS challenge packet was badly formed"));
+ crStop(0);
+ }
+ logevent("Received TIS challenge");
+ if (challengelen > sizeof(s->prompt) - 1)
+ challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
+ memcpy(s->prompt, challenge, challengelen);
+ /* Prompt heuristic comes from OpenSSH */
+ strncpy(s->prompt + challengelen,
+ memchr(s->prompt, '\n', challengelen) ?
+ "": "\r\nResponse: ",
+ (sizeof s->prompt) - challengelen);
+ s->prompt[(sizeof s->prompt) - 1] = '\0';
+ }
+ }
+ if (ssh->cfg.try_tis_auth &&
+ (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
+ !s->ccard_auth_refused) {
+ s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
+ logevent("Requested CryptoCard authentication");
+ send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
+ crWaitUntil(pktin);
+ if (pktin->type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
+ logevent("CryptoCard authentication declined");
+ c_write_str(ssh, "CryptoCard authentication refused.\r\n");
+ s->ccard_auth_refused = 1;
+ continue;
+ } else {
+ char *challenge;
+ int challengelen;
+
+ ssh_pkt_getstring(pktin, &challenge, &challengelen);
+ if (!challenge) {
+ bombout(("CryptoCard challenge packet was badly formed"));
+ crStop(0);
+ }
+ logevent("Received CryptoCard challenge");
+ if (challengelen > sizeof(s->prompt) - 1)
+ challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
+ memcpy(s->prompt, challenge, challengelen);
+ strncpy(s->prompt + challengelen,
+ memchr(s->prompt, '\n', challengelen) ?
+ "" : "\r\nResponse: ",
+ sizeof(s->prompt) - challengelen);
+ s->prompt[sizeof(s->prompt) - 1] = '\0';
+ }
+ }
+ if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
+ sprintf(s->prompt, "%.90s@%.90s's password: ",
+ s->username, ssh->savedhost);
+ }
+ if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
+ char *comment = NULL;
+ int type;
+ char msgbuf[256];
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "Trying public key authentication.\r\n");
+ logeventf(ssh, "Trying public key \"%s\"",
+ filename_to_str(&ssh->cfg.keyfile));
+ type = key_type(&ssh->cfg.keyfile);
+ if (type != SSH_KEYTYPE_SSH1) {
+ sprintf(msgbuf, "Key is of wrong type (%s)",
+ key_type_to_str(type));
+ logevent(msgbuf);
+ c_write_str(ssh, msgbuf);
+ c_write_str(ssh, "\r\n");
+ s->tried_publickey = 1;
+ continue;
+ }
+ if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "No passphrase required.\r\n");
+ goto tryauth;
+ }
+ sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
+ sfree(comment);
+ }
+
+ /*
+ * Show password prompt, having first obtained it via a TIS
+ * or CryptoCard exchange if we're doing TIS or CryptoCard
+ * authentication.
+ */
+ if (ssh_get_line) {
+ if (!ssh_get_line(s->prompt, s->password,
+ sizeof(s->password), TRUE)) {
+ /*
+ * get_line failed to get a password (for example
+ * because one was supplied on the command line
+ * which has already failed to work). Terminate.
+ */
+ send_packet(ssh, SSH1_MSG_DISCONNECT,
+ PKT_STR, "No more passwords available to try",
+ PKT_END);
+ logevent("Unable to authenticate");
+ connection_fatal(ssh->frontend, "Unable to authenticate");
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ crStop(1);
+ }
+ } else {
+ /* Prompt may have come from server. We've munged it a bit, so
+ * we know it to be zero-terminated at least once. */
+ int ret; /* need not be saved over crReturn */
+ c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
+ s->pos = 0;
+
+ setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
+ do {
+ crWaitUntil(!pktin);
+ ret = process_userpass_input(ssh, in, inlen);
+ } while (ret == 0);
+ if (ret < 0)
+ cleanup_exit(0);
+ c_write_str(ssh, "\r\n");
+ }
+
+ tryauth:
+ if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
+ /*
+ * Try public key authentication with the specified
+ * key file.
+ */
+ s->tried_publickey = 1;
+
+ {
+ const char *error = NULL;
+ int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
+ &error);
+ if (ret == 0) {
+ c_write_str(ssh, "Couldn't load private key from ");
+ c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
+ c_write_str(ssh, " (");
+ c_write_str(ssh, error);
+ c_write_str(ssh, ").\r\n");
+ continue; /* go and try password */
+ }
+ if (ret == -1) {
+ c_write_str(ssh, "Wrong passphrase.\r\n");
+ s->tried_publickey = 0;
+ continue; /* try again */
+ }
+ }
+
+ /*
+ * Send a public key attempt.
+ */
+ send_packet(ssh, SSH1_CMSG_AUTH_RSA,
+ PKT_BIGNUM, s->key.modulus, PKT_END);
+
+ crWaitUntil(pktin);
+ if (pktin->type == SSH1_SMSG_FAILURE) {
+ c_write_str(ssh, "Server refused our public key.\r\n");
+ continue; /* go and try password */
+ }
+ if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
+ bombout(("Bizarre response to offer of public key"));
+ crStop(0);
+ }
+
+ {
+ int i;
+ unsigned char buffer[32];
+ Bignum challenge, response;
+
+ if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
+ bombout(("Server's RSA challenge was badly formatted"));
+ crStop(0);
+ }
+ response = rsadecrypt(challenge, &s->key);
+ freebn(s->key.private_exponent);/* burn the evidence */
+
+ for (i = 0; i < 32; i++) {
+ buffer[i] = bignum_byte(response, 31 - i);
+ }
+
+ MD5Init(&md5c);
+ MD5Update(&md5c, buffer, 32);
+ MD5Update(&md5c, s->session_id, 16);
+ MD5Final(buffer, &md5c);
+
+ send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
+ PKT_DATA, buffer, 16, PKT_END);
+
+ freebn(challenge);
+ freebn(response);
+ }
+
+ crWaitUntil(pktin);
+ if (pktin->type == SSH1_SMSG_FAILURE) {
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "Failed to authenticate with"
+ " our public key.\r\n");
+ continue; /* go and try password */
+ } else if (pktin->type != SSH1_SMSG_SUCCESS) {
+ bombout(("Bizarre response to RSA authentication response"));
+ crStop(0);
+ }
+
+ break; /* we're through! */
+ } else {
+ if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
+ /*
+ * Defence against traffic analysis: we send a
+ * whole bunch of packets containing strings of
+ * different lengths. One of these strings is the
+ * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
+ * The others are all random data in
+ * SSH1_MSG_IGNORE packets. This way a passive
+ * listener can't tell which is the password, and
+ * hence can't deduce the password length.
+ *
+ * Anybody with a password length greater than 16
+ * bytes is going to have enough entropy in their
+ * password that a listener won't find it _that_
+ * much help to know how long it is. So what we'll
+ * do is:
+ *
+ * - if password length < 16, we send 15 packets
+ * containing string lengths 1 through 15
+ *
+ * - otherwise, we let N be the nearest multiple
+ * of 8 below the password length, and send 8
+ * packets containing string lengths N through
+ * N+7. This won't obscure the order of
+ * magnitude of the password length, but it will
+ * introduce a bit of extra uncertainty.
+ *
+ * A few servers (the old 1.2.18 through 1.2.22)
+ * can't deal with SSH1_MSG_IGNORE. For these
+ * servers, we need an alternative defence. We make
+ * use of the fact that the password is interpreted
+ * as a C string: so we can append a NUL, then some
+ * random data.
+ *
+ * One server (a Cisco one) can deal with neither
+ * SSH1_MSG_IGNORE _nor_ a padded password string.
+ * For this server we are left with no defences
+ * against password length sniffing.
+ */
+ if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
+ /*
+ * The server can deal with SSH1_MSG_IGNORE, so
+ * we can use the primary defence.
+ */
+ int bottom, top, pwlen, i;
+ char *randomstr;
+
+ pwlen = strlen(s->password);
+ if (pwlen < 16) {
+ bottom = 0; /* zero length passwords are OK! :-) */
+ top = 15;
+ } else {
+ bottom = pwlen & ~7;
+ top = bottom + 7;
+ }
+
+ assert(pwlen >= bottom && pwlen <= top);
+
+ randomstr = snewn(top + 1, char);
+
+ for (i = bottom; i <= top; i++) {
+ if (i == pwlen) {
+ defer_packet(ssh, s->pwpkt_type,
+ PKTT_PASSWORD, PKT_STR, s->password,
+ PKTT_OTHER, PKT_END);
+ } else {
+ for (j = 0; j < i; j++) {
+ do {
+ randomstr[j] = random_byte();
+ } while (randomstr[j] == '\0');
+ }
+ randomstr[i] = '\0';
+ defer_packet(ssh, SSH1_MSG_IGNORE,
+ PKT_STR, randomstr, PKT_END);
+ }
+ }
+ logevent("Sending password with camouflage packets");
+ ssh_pkt_defersend(ssh);
+ sfree(randomstr);
+ }
+ else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
+ /*
+ * The server can't deal with SSH1_MSG_IGNORE
+ * but can deal with padded passwords, so we
+ * can use the secondary defence.
+ */
+ char string[64];
+ char *ss;
+ int len;
+
+ len = strlen(s->password);
+ if (len < sizeof(string)) {
+ ss = string;
+ strcpy(string, s->password);
+ len++; /* cover the zero byte */
+ while (len < sizeof(string)) {
+ string[len++] = (char) random_byte();
+ }
+ } else {
+ ss = s->password;
+ }
+ logevent("Sending length-padded password");
+ send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
+ PKT_INT, len, PKT_DATA, ss, len,
+ PKTT_OTHER, PKT_END);
+ } else {
+ /*
+ * The server has _both_
+ * BUG_CHOKES_ON_SSH1_IGNORE and
+ * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
+ * therefore nothing we can do.
+ */
+ int len;
+ len = strlen(s->password);
+ logevent("Sending unpadded password");
+ send_packet(ssh, s->pwpkt_type,
+ PKTT_PASSWORD, PKT_INT, len,
+ PKT_DATA, s->password, len,
+ PKTT_OTHER, PKT_END);
+ }
+ } else {
+ send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
+ PKT_STR, s->password, PKTT_OTHER, PKT_END);
+ }
+ }
+ logevent("Sent password");
+ memset(s->password, 0, strlen(s->password));
+ crWaitUntil(pktin);
+ if (pktin->type == SSH1_SMSG_FAILURE) {
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "Access denied\r\n");
+ logevent("Authentication refused");
+ } else if (pktin->type != SSH1_SMSG_SUCCESS) {
+ bombout(("Strange packet received, type %d", pktin->type));
+ crStop(0);
+ }
+ }
+
+ logevent("Authentication successful");
+
+ crFinish(1);
+}
+
+void sshfwd_close(struct ssh_channel *c)
+{
+ Ssh ssh = c->ssh;
+
+ if (ssh->state != SSH_STATE_SESSION) {
+ assert(ssh->state == SSH_STATE_CLOSED);
+ return;
+ }
+
+ if (c && !c->closes) {
+ /*
+ * If the channel's remoteid is -1, we have sent
+ * CHANNEL_OPEN for this channel, but it hasn't even been
+ * acknowledged by the server. So we must set a close flag
+ * on it now, and then when the server acks the channel
+ * open, we can close it then.
+ */
+ if (((int)c->remoteid) != -1) {
+ if (ssh->version == 1) {
+ send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
+ PKT_END);
+ } else {
+ struct Packet *pktout;
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+ }
+ c->closes = 1; /* sent MSG_CLOSE */
+ if (c->type == CHAN_X11) {
+ c->u.x11.s = NULL;
+ logevent("Forwarded X11 connection terminated");
+ } else if (c->type == CHAN_SOCKDATA ||
+ c->type == CHAN_SOCKDATA_DORMANT) {
+ c->u.pfd.s = NULL;
+ logevent("Forwarded port closed");
+ }
+ }
+}
+
+int sshfwd_write(struct ssh_channel *c, char *buf, int len)
+{
+ Ssh ssh = c->ssh;
+
+ if (ssh->state != SSH_STATE_SESSION) {
+ assert(ssh->state == SSH_STATE_CLOSED);
+ return 0;
+ }
+
+ if (ssh->version == 1) {
+ send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
+ PKT_INT, c->remoteid,
+ PKTT_DATA,
+ PKT_INT, len, PKT_DATA, buf, len,
+ PKTT_OTHER, PKT_END);
+ /*
+ * In SSH1 we can return 0 here - implying that forwarded
+ * connections are never individually throttled - because
+ * the only circumstance that can cause throttling will be
+ * the whole SSH connection backing up, in which case
+ * _everything_ will be throttled as a whole.
+ */
+ return 0;
+ } else {
+ ssh2_add_channel_data(c, buf, len);
+ return ssh2_try_send(c);
+ }
+}
+
+void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
+{
+ Ssh ssh = c->ssh;
+
+ if (ssh->state != SSH_STATE_SESSION) {
+ assert(ssh->state == SSH_STATE_CLOSED);
+ return;
+ }
+
+ if (ssh->version == 1) {
+ if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
+ c->v.v1.throttling = 0;
+ ssh1_throttle(ssh, -1);
+ }
+ } else {
+ ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
+ }
+}
+
+static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
+{
+ char *string;
+ int stringlen, bufsize;
+
+ ssh_pkt_getstring(pktin, &string, &stringlen);
+ if (string == NULL) {
+ bombout(("Incoming terminal data packet was badly formed"));
+ return;
+ }
+
+ bufsize = from_backend(ssh->frontend, pktin->type == SSH1_SMSG_STDERR_DATA,
+ string, stringlen);
+ if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
+ ssh->v1_stdout_throttling = 1;
+ ssh1_throttle(ssh, +1);
+ }
+}
+
+static void ssh1_smsg_x11_open(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side is trying to open a channel to talk to our
+ * X-Server. Give them back a local channel number. */
+ struct ssh_channel *c;
+ int remoteid = ssh_pkt_getuint32(pktin);
+
+ logevent("Received X11 connect request");
+ /* Refuse if X11 forwarding is disabled. */
+ if (!ssh->X11_fwd_enabled) {
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ logevent("Rejected X11 connect request");
+ } else {
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+
+ if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
+ ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
+ logevent("Opening X11 forward connection failed");
+ sfree(c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ logevent
+ ("Opening X11 forward connection succeeded");
+ c->remoteid = remoteid;
+ c->localid = alloc_channel_id(ssh);
+ c->closes = 0;
+ c->v.v1.throttling = 0;
+ c->type = CHAN_X11; /* identify channel type */
+ add234(ssh->channels, c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT,
+ c->localid, PKT_END);
+ logevent("Opened X11 forward channel");
+ }
+ }
+}
+
+static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side is trying to open a channel to talk to our
+ * agent. Give them back a local channel number. */
+ struct ssh_channel *c;
+ int remoteid = ssh_pkt_getuint32(pktin);
+
+ /* Refuse if agent forwarding is disabled. */
+ if (!ssh->agentfwd_enabled) {
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+ c->remoteid = remoteid;
+ c->localid = alloc_channel_id(ssh);
+ c->closes = 0;
+ c->v.v1.throttling = 0;
+ c->type = CHAN_AGENT; /* identify channel type */
+ c->u.a.lensofar = 0;
+ add234(ssh->channels, c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT, c->localid,
+ PKT_END);
+ }
+}
+
+static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side is trying to open a channel to talk to a
+ * forwarded port. Give them back a local channel number. */
+ struct ssh_channel *c;
+ struct ssh_rportfwd pf;
+ int remoteid;
+ int hostsize, port;
+ char *host, buf[1024];
+ const char *e;
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+
+ remoteid = ssh_pkt_getuint32(pktin);
+ ssh_pkt_getstring(pktin, &host, &hostsize);
+ port = ssh_pkt_getuint32(pktin);
+
+ if (hostsize >= lenof(pf.dhost))
+ hostsize = lenof(pf.dhost)-1;
+ memcpy(pf.dhost, host, hostsize);
+ pf.dhost[hostsize] = '\0';
+ pf.dport = port;
+
+ if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
+ sprintf(buf, "Rejected remote port open request for %s:%d",
+ pf.dhost, port);
+ logevent(buf);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ sprintf(buf, "Received remote port open request for %s:%d",
+ pf.dhost, port);
+ logevent(buf);
+ e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
+ c, &ssh->cfg);
+ if (e != NULL) {
+ char buf[256];
+ sprintf(buf, "Port open failed: %s", e);
+ logevent(buf);
+ sfree(c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ c->remoteid = remoteid;
+ c->localid = alloc_channel_id(ssh);
+ c->closes = 0;
+ c->v.v1.throttling = 0;
+ c->type = CHAN_SOCKDATA; /* identify channel type */
+ add234(ssh->channels, c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT,
+ c->localid, PKT_END);
+ logevent("Forwarded port opened successfully");
+ }
+ }
+}
+
+static void ssh1_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
+{
+ unsigned int remoteid = ssh_pkt_getuint32(pktin);
+ unsigned int localid = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+
+ c = find234(ssh->channels, &remoteid, ssh_channelfind);
+ if (c && c->type == CHAN_SOCKDATA_DORMANT) {
+ c->remoteid = localid;
+ c->type = CHAN_SOCKDATA;
+ c->v.v1.throttling = 0;
+ pfd_confirm(c->u.pfd.s);
+ }
+
+ if (c && c->closes) {
+ /*
+ * We have a pending close on this channel,
+ * which we decided on before the server acked
+ * the channel open. So now we know the
+ * remoteid, we can close it again.
+ */
+ send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
+ PKT_INT, c->remoteid, PKT_END);
+ }
+}
+
+static void ssh1_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
+{
+ unsigned int remoteid = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+
+ c = find234(ssh->channels, &remoteid, ssh_channelfind);
+ if (c && c->type == CHAN_SOCKDATA_DORMANT) {
+ logevent("Forwarded connection refused by server");
+ pfd_close(c->u.pfd.s);
+ del234(ssh->channels, c);
+ sfree(c);
+ }
+}
+
+static void ssh1_msg_channel_close(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side closes a channel. */
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (c && ((int)c->remoteid) != -1) {
+ int closetype;
+ closetype =
+ (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
+
+ if ((c->closes == 0) && (c->type == CHAN_X11)) {
+ logevent("Forwarded X11 connection terminated");
+ assert(c->u.x11.s != NULL);
+ x11_close(c->u.x11.s);
+ c->u.x11.s = NULL;
+ }
+ if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
+ logevent("Forwarded port closed");
+ assert(c->u.pfd.s != NULL);
+ pfd_close(c->u.pfd.s);
+ c->u.pfd.s = NULL;
+ }
+
+ c->closes |= (closetype << 2); /* seen this message */
+ if (!(c->closes & closetype)) {
+ send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
+ PKT_END);
+ c->closes |= closetype; /* sent it too */
+ }
+
+ if (c->closes == 15) {
+ del234(ssh->channels, c);
+ sfree(c);
+ }
+ } else {
+ bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
+ pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
+ "_CONFIRMATION", c ? "half-open" : "nonexistent",
+ i));
+ }
+}
+
+static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
+{
+ /* Data sent down one of our channels. */
+ int i = ssh_pkt_getuint32(pktin);
+ char *p;
+ int len;
+ struct ssh_channel *c;
+
+ ssh_pkt_getstring(pktin, &p, &len);
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (c) {
+ int bufsize = 0;
+ switch (c->type) {
+ case CHAN_X11:
+ bufsize = x11_send(c->u.x11.s, p, len);
+ break;
+ case CHAN_SOCKDATA:
+ bufsize = pfd_send(c->u.pfd.s, p, len);
+ break;
+ case CHAN_AGENT:
+ /* Data for an agent message. Buffer it. */
+ while (len > 0) {
+ if (c->u.a.lensofar < 4) {
+ int l = min(4 - c->u.a.lensofar, len);
+ memcpy(c->u.a.msglen + c->u.a.lensofar, p,
+ l);
+ p += l;
+ len -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == 4) {
+ c->u.a.totallen =
+ 4 + GET_32BIT(c->u.a.msglen);
+ c->u.a.message = snewn(c->u.a.totallen,
+ unsigned char);
+ memcpy(c->u.a.message, c->u.a.msglen, 4);
+ }
+ if (c->u.a.lensofar >= 4 && len > 0) {
+ int l =
+ min(c->u.a.totallen - c->u.a.lensofar,
+ len);
+ memcpy(c->u.a.message + c->u.a.lensofar, p,
+ l);
+ p += l;
+ len -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == c->u.a.totallen) {
+ void *reply;
+ int replylen;
+ if (agent_query(c->u.a.message,
+ c->u.a.totallen,
+ &reply, &replylen,
+ ssh_agentf_callback, c))
+ ssh_agentf_callback(c, reply, replylen);
+ sfree(c->u.a.message);
+ c->u.a.lensofar = 0;
+ }
+ }
+ bufsize = 0; /* agent channels never back up */
+ break;
+ }
+ if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
+ c->v.v1.throttling = 1;
+ ssh1_throttle(ssh, +1);
+ }
+ }
+}
+
+static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
+{
+ char buf[100];
+ ssh->exitcode = ssh_pkt_getuint32(pktin);
+ sprintf(buf, "Server sent command exit status %d",
+ ssh->exitcode);
+ logevent(buf);
+ send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
+ /*
+ * In case `helpful' firewalls or proxies tack
+ * extra human-readable text on the end of the
+ * session which we might mistake for another
+ * encrypted packet, we close the session once
+ * we've sent EXIT_CONFIRMATION.
+ */
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+}
+
+static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
+ struct Packet *pktin)
+{
+ crBegin(ssh->do_ssh1_connection_crstate);
+
+ ssh->packet_dispatch[SSH1_SMSG_STDOUT_DATA] =
+ ssh->packet_dispatch[SSH1_SMSG_STDERR_DATA] =
+ ssh1_smsg_stdout_stderr_data;
+
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION] =
+ ssh1_msg_channel_open_confirmation;
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_FAILURE] =
+ ssh1_msg_channel_open_failure;
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE] =
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION] =
+ ssh1_msg_channel_close;
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_DATA] = ssh1_msg_channel_data;
+ ssh->packet_dispatch[SSH1_SMSG_EXIT_STATUS] = ssh1_smsg_exit_status;
+
+ if (ssh->cfg.agentfwd && agent_exists()) {
+ logevent("Requesting agent forwarding");
+ send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
+ do {
+ crReturnV;
+ } while (!pktin);
+ if (pktin->type != SSH1_SMSG_SUCCESS
+ && pktin->type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crStopV;
+ } else if (pktin->type == SSH1_SMSG_FAILURE) {
+ logevent("Agent forwarding refused");
+ } else {
+ logevent("Agent forwarding enabled");
+ ssh->agentfwd_enabled = TRUE;
+ ssh->packet_dispatch[SSH1_SMSG_AGENT_OPEN] = ssh1_smsg_agent_open;
+ }
+ }
+
+ if (ssh->cfg.x11_forward) {
+ char proto[20], data[64];
+ logevent("Requesting X11 forwarding");
+ ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
+ data, sizeof(data), ssh->cfg.x11_auth);
+ x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
+ if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
+ send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
+ PKT_STR, proto, PKT_STR, data,
+ PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
+ PKT_END);
+ } else {
+ send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
+ PKT_STR, proto, PKT_STR, data, PKT_END);
+ }
+ do {
+ crReturnV;
+ } while (!pktin);
+ if (pktin->type != SSH1_SMSG_SUCCESS
+ && pktin->type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crStopV;
+ } else if (pktin->type == SSH1_SMSG_FAILURE) {
+ logevent("X11 forwarding refused");
+ } else {
+ logevent("X11 forwarding enabled");
+ ssh->X11_fwd_enabled = TRUE;
+ ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
+ }
+ }
+
+ {
+ char type;
+ int n;
+ int sport,dport,sserv,dserv;
+ char sports[256], dports[256], saddr[256], host[256];
+
+ ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
+ /* Add port forwardings. */
+ ssh->portfwd_strptr = ssh->cfg.portfwd;
+ while (*ssh->portfwd_strptr) {
+ type = *ssh->portfwd_strptr++;
+ saddr[0] = '\0';
+ n = 0;
+ while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
+ if (*ssh->portfwd_strptr == ':') {
+ /*
+ * We've seen a colon in the middle of the
+ * source port number. This means that
+ * everything we've seen until now is the
+ * source _address_, so we'll move it into
+ * saddr and start sports from the beginning
+ * again.
+ */
+ ssh->portfwd_strptr++;
+ sports[n] = '\0';
+ strcpy(saddr, sports);
+ n = 0;
+ }
+ if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
+ }
+ sports[n] = 0;
+ if (type != 'D') {
+ if (*ssh->portfwd_strptr == '\t')
+ ssh->portfwd_strptr++;
+ n = 0;
+ while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
+ if (n < 255) host[n++] = *ssh->portfwd_strptr++;
+ }
+ host[n] = 0;
+ if (*ssh->portfwd_strptr == ':')
+ ssh->portfwd_strptr++;
+ n = 0;
+ while (*ssh->portfwd_strptr) {
+ if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
+ }
+ dports[n] = 0;
+ ssh->portfwd_strptr++;
+ dport = atoi(dports);
+ dserv = 0;
+ if (dport == 0) {
+ dserv = 1;
+ dport = net_service_lookup(dports);
+ if (!dport) {
+ logeventf(ssh, "Service lookup failed for"
+ " destination port \"%s\"", dports);
+ }
+ }
+ } else {
+ while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
+ dport = dserv = -1;
+ ssh->portfwd_strptr++; /* eat the NUL and move to next one */
+ }
+ sport = atoi(sports);
+ sserv = 0;
+ if (sport == 0) {
+ sserv = 1;
+ sport = net_service_lookup(sports);
+ if (!sport) {
+ logeventf(ssh, "Service lookup failed for source"
+ " port \"%s\"", sports);
+ }
+ }
+ if (sport && dport) {
+ /* Set up a description of the source port. */
+ static char *sportdesc;
+ sportdesc = dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
+ (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
+ (int)(*saddr?1:0), ":",
+ (int)(sserv ? strlen(sports) : 0), sports,
+ sserv, "(", sport, sserv, ")");
+ if (type == 'L') {
+ /* Verbose description of the destination port */
+ char *dportdesc = dupprintf("%s:%.*s%.*s%d%.*s",
+ host,
+ (int)(dserv ? strlen(dports) : 0), dports,
+ dserv, "(", dport, dserv, ")");
+ const char *err = pfd_addforward(host, dport,
+ *saddr ? saddr : NULL,
+ sport, ssh, &ssh->cfg);
+ if (err) {
+ logeventf(ssh, "Local port %s forward to %s"
+ " failed: %s", sportdesc, dportdesc, err);
+ } else {
+ logeventf(ssh, "Local port %s forwarding to %s",
+ sportdesc, dportdesc);
+ }
+ sfree(dportdesc);
+ } else if (type == 'D') {
+ const char *err = pfd_addforward(NULL, -1,
+ *saddr ? saddr : NULL,
+ sport, ssh, &ssh->cfg);
+ if (err) {
+ logeventf(ssh, "Local port %s SOCKS dynamic forward"
+ " setup failed: %s", sportdesc, err);
+ } else {
+ logeventf(ssh, "Local port %s doing SOCKS"
+ " dynamic forwarding", sportdesc);
+ }
+ } else {
+ struct ssh_rportfwd *pf;
+ pf = snew(struct ssh_rportfwd);
+ strcpy(pf->dhost, host);
+ pf->dport = dport;
+ if (*saddr) {
+ logeventf(ssh,
+ "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
+ saddr, sport);
+ }
+ if (add234(ssh->rportfwds, pf) != pf) {
+ logeventf(ssh,
+ "Duplicate remote port forwarding to %s:%d",
+ host, dport);
+ sfree(pf);
+ } else {
+ logeventf(ssh, "Requesting remote port %.*s%.*s%d%.*s"
+ " forward to %s:%.*s%.*s%d%.*s",
+ (int)(sserv ? strlen(sports) : 0), sports,
+ sserv, "(", sport, sserv, ")",
+ host,
+ (int)(dserv ? strlen(dports) : 0), dports,
+ dserv, "(", dport, dserv, ")");
+ send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
+ PKT_INT, sport,
+ PKT_STR, host,
+ PKT_INT, dport,
+ PKT_END);
+ do {
+ crReturnV;
+ } while (!pktin);
+ if (pktin->type != SSH1_SMSG_SUCCESS
+ && pktin->type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crStopV;
+ } else if (pktin->type == SSH1_SMSG_FAILURE) {
+ c_write_str(ssh, "Server refused port"
+ " forwarding\r\n");
+ logevent("Server refused this port forwarding");
+ } else {
+ logevent("Remote port forwarding enabled");
+ ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] =
+ ssh1_msg_port_open;
+ }
+ }
+ }
+ sfree(sportdesc);
+ }
+ }
+ }
+
+ if (!ssh->cfg.nopty) {
+ /* Unpick the terminal-speed string. */
+ /* XXX perhaps we should allow no speeds to be sent. */
+ ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
+ sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
+ /* Send the pty request. */
+ send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
+ PKT_STR, ssh->cfg.termtype,
+ PKT_INT, ssh->term_height,
+ PKT_INT, ssh->term_width,
+ PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
+ PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
+ PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
+ PKT_CHAR, 0, PKT_END);
+ ssh->state = SSH_STATE_INTERMED;
+ do {
+ crReturnV;
+ } while (!pktin);
+ if (pktin->type != SSH1_SMSG_SUCCESS
+ && pktin->type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crStopV;
+ } else if (pktin->type == SSH1_SMSG_FAILURE) {
+ c_write_str(ssh, "Server refused to allocate pty\r\n");
+ ssh->editing = ssh->echoing = 1;
+ }
+ logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
+ ssh->ospeed, ssh->ispeed);
+ } else {
+ ssh->editing = ssh->echoing = 1;
+ }
+
+ if (ssh->cfg.compression) {
+ send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
+ do {
+ crReturnV;
+ } while (!pktin);
+ if (pktin->type != SSH1_SMSG_SUCCESS
+ && pktin->type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crStopV;
+ } else if (pktin->type == SSH1_SMSG_FAILURE) {
+ c_write_str(ssh, "Server refused to compress\r\n");
+ }
+ logevent("Started compression");
+ ssh->v1_compressing = TRUE;
+ ssh->cs_comp_ctx = zlib_compress_init();
+ logevent("Initialised zlib (RFC1950) compression");
+ ssh->sc_comp_ctx = zlib_decompress_init();
+ logevent("Initialised zlib (RFC1950) decompression");
+ }
+
+ /*
+ * Start the shell or command.
+ *
+ * Special case: if the first-choice command is an SSH2
+ * subsystem (hence not usable here) and the second choice
+ * exists, we fall straight back to that.
+ */
+ {
+ char *cmd = ssh->cfg.remote_cmd_ptr;
+
+ if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
+ cmd = ssh->cfg.remote_cmd_ptr2;
+ ssh->fallback_cmd = TRUE;
+ }
+ if (*cmd)
+ send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
+ else
+ send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
+ logevent("Started session");
+ }
+
+ ssh->state = SSH_STATE_SESSION;
+ if (ssh->size_needed)
+ ssh_size(ssh, ssh->term_width, ssh->term_height);
+ if (ssh->eof_needed)
+ ssh_special(ssh, TS_EOF);
+
+ if (ssh->ldisc)
+ ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
+ ssh->send_ok = 1;
+ ssh->channels = newtree234(ssh_channelcmp);
+ while (1) {
+
+ /*
+ * By this point, most incoming packets are already being
+ * handled by the dispatch table, and we need only pay
+ * attention to the unusual ones.
+ */
+
+ crReturnV;
+ if (pktin) {
+ if (pktin->type == SSH1_SMSG_SUCCESS) {
+ /* may be from EXEC_SHELL on some servers */
+ } else if (pktin->type == SSH1_SMSG_FAILURE) {
+ /* may be from EXEC_SHELL on some servers
+ * if no pty is available or in other odd cases. Ignore */
+ } else {
+ bombout(("Strange packet received: type %d", pktin->type));
+ crStopV;
+ }
+ } else {
+ while (inlen > 0) {
+ int len = min(inlen, 512);
+ send_packet(ssh, SSH1_CMSG_STDIN_DATA, PKTT_DATA,
+ PKT_INT, len, PKT_DATA, in, len,
+ PKTT_OTHER, PKT_END);
+ in += len;
+ inlen -= len;
+ }
+ }
+ }
+
+ crFinishV;
+}
+
+/*
+ * Handle the top-level SSH2 protocol.
+ */
+static void ssh1_msg_debug(Ssh ssh, struct Packet *pktin)
+{
+ char *buf, *msg;
+ int msglen;
+
+ ssh_pkt_getstring(pktin, &msg, &msglen);
+ buf = dupprintf("Remote debug message: %.*s", msglen, msg);
+ logevent(buf);
+ sfree(buf);
+}
+
+static void ssh1_msg_disconnect(Ssh ssh, struct Packet *pktin)
+{
+ /* log reason code in disconnect message */
+ char *msg;
+ int msglen;
+
+ ssh_pkt_getstring(pktin, &msg, &msglen);
+ bombout(("Server sent disconnect message:\n\"%.*s\"", msglen, msg));
+}
+
+void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
+{
+ /* Do nothing, because we're ignoring it! Duhh. */
+}
+
+static void ssh1_protocol_setup(Ssh ssh)
+{
+ int i;
+
+ /*
+ * Most messages are handled by the coroutines.
+ */
+ for (i = 0; i < 256; i++)
+ ssh->packet_dispatch[i] = NULL;
+
+ /*
+ * These special message types we install handlers for.
+ */
+ ssh->packet_dispatch[SSH1_MSG_DISCONNECT] = ssh1_msg_disconnect;
+ ssh->packet_dispatch[SSH1_MSG_IGNORE] = ssh_msg_ignore;
+ ssh->packet_dispatch[SSH1_MSG_DEBUG] = ssh1_msg_debug;
+}
+
+static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
+ struct Packet *pktin)
+{
+ if (ssh->state == SSH_STATE_CLOSED)
+ return;
+
+ if (pktin && ssh->packet_dispatch[pktin->type]) {
+ ssh->packet_dispatch[pktin->type](ssh, pktin);
+ return;
+ }
+
+ if (!ssh->protocol_initial_phase_done) {
+ if (do_ssh1_login(ssh, in, inlen, pktin))
+ ssh->protocol_initial_phase_done = TRUE;
+ else
+ return;
+ }
+
+ do_ssh1_connection(ssh, in, inlen, pktin);
+}
+
+/*
+ * Utility routine for decoding comma-separated strings in KEXINIT.
+ */
+static int in_commasep_string(char *needle, char *haystack, int haylen)
+{
+ int needlen;
+ if (!needle || !haystack) /* protect against null pointers */
+ return 0;
+ needlen = strlen(needle);
+ while (1) {
+ /*
+ * Is it at the start of the string?
+ */
+ if (haylen >= needlen && /* haystack is long enough */
+ !memcmp(needle, haystack, needlen) && /* initial match */
+ (haylen == needlen || haystack[needlen] == ',')
+ /* either , or EOS follows */
+ )
+ return 1;
+ /*
+ * If not, search for the next comma and resume after that.
+ * If no comma found, terminate.
+ */
+ while (haylen > 0 && *haystack != ',')
+ haylen--, haystack++;
+ if (haylen == 0)
+ return 0;
+ haylen--, haystack++; /* skip over comma itself */
+ }
+}
+
+/*
+ * SSH2 key creation method.
+ */
+static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
+ unsigned char *sessid, char chr,
+ unsigned char *keyspace)
+{
+ SHA_State s;
+ /* First 20 bytes. */
+ SHA_Init(&s);
+ if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
+ sha_mpint(&s, K);
+ SHA_Bytes(&s, H, 20);
+ SHA_Bytes(&s, &chr, 1);
+ SHA_Bytes(&s, sessid, 20);
+ SHA_Final(&s, keyspace);
+ /* Next 20 bytes. */
+ SHA_Init(&s);
+ if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
+ sha_mpint(&s, K);
+ SHA_Bytes(&s, H, 20);
+ SHA_Bytes(&s, keyspace, 20);
+ SHA_Final(&s, keyspace + 20);
+}
+
+/*
+ * Handle the SSH2 transport layer.
+ */
+static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
+ struct Packet *pktin)
+{
+ struct do_ssh2_transport_state {
+ int nbits, pbits, warn;
+ Bignum p, g, e, f, K;
+ int kex_init_value, kex_reply_value;
+ const struct ssh_mac **maclist;
+ int nmacs;
+ const struct ssh2_cipher *cscipher_tobe;
+ const struct ssh2_cipher *sccipher_tobe;
+ const struct ssh_mac *csmac_tobe;
+ const struct ssh_mac *scmac_tobe;
+ const struct ssh_compress *cscomp_tobe;
+ const struct ssh_compress *sccomp_tobe;
+ char *hostkeydata, *sigdata, *keystr, *fingerprint;
+ int hostkeylen, siglen;
+ void *hkey; /* actual host key */
+ unsigned char exchange_hash[20];
+ int n_preferred_ciphers;
+ const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
+ const struct ssh_compress *preferred_comp;
+ int first_kex;
+ struct Packet *pktout;
+ };
+ crState(do_ssh2_transport_state);
+
+ crBegin(ssh->do_ssh2_transport_crstate);
+
+ s->cscipher_tobe = s->sccipher_tobe = NULL;
+ s->csmac_tobe = s->scmac_tobe = NULL;
+ s->cscomp_tobe = s->sccomp_tobe = NULL;
+
+ s->first_kex = 1;
+
+ {
+ int i;
+ /*
+ * Set up the preferred ciphers. (NULL => warn below here)
+ */
+ s->n_preferred_ciphers = 0;
+ for (i = 0; i < CIPHER_MAX; i++) {
+ switch (ssh->cfg.ssh_cipherlist[i]) {
+ case CIPHER_BLOWFISH:
+ s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
+ break;
+ case CIPHER_DES:
+ if (ssh->cfg.ssh2_des_cbc) {
+ s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
+ }
+ break;
+ case CIPHER_3DES:
+ s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
+ break;
+ case CIPHER_AES:
+ s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
+ break;
+ case CIPHER_WARN:
+ /* Flag for later. Don't bother if it's the last in
+ * the list. */
+ if (i < CIPHER_MAX - 1) {
+ s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
+ }
+ break;
+ }
+ }
+ }
+
+ /*
+ * Set up preferred compression.
+ */
+ if (ssh->cfg.compression)
+ s->preferred_comp = &ssh_zlib;
+ else
+ s->preferred_comp = &ssh_comp_none;
+
+ /*
+ * Be prepared to work around the buggy MAC problem.
+ */
+ if (ssh->remote_bugs & BUG_SSH2_HMAC)
+ s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
+ else
+ s->maclist = macs, s->nmacs = lenof(macs);
+
+ begin_key_exchange:
+ {
+ int i, j, cipherstr_started;
+
+ /*
+ * Enable queueing of outgoing auth- or connection-layer
+ * packets while we are in the middle of a key exchange.
+ */
+ ssh->queueing = TRUE;
+
+ /*
+ * Flag that KEX is in progress.
+ */
+ ssh->kex_in_progress = TRUE;
+
+ /*
+ * Construct and send our key exchange packet.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_KEXINIT);
+ for (i = 0; i < 16; i++)
+ ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
+ /* List key exchange algorithms. */
+ ssh2_pkt_addstring_start(s->pktout);
+ for (i = 0; i < lenof(kex_algs); i++) {
+ if (kex_algs[i] == &ssh_diffiehellman_gex &&
+ (ssh->remote_bugs & BUG_SSH2_DH_GEX))
+ continue;
+ ssh2_pkt_addstring_str(s->pktout, kex_algs[i]->name);
+ if (i < lenof(kex_algs) - 1)
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ }
+ /* List server host key algorithms. */
+ ssh2_pkt_addstring_start(s->pktout);
+ for (i = 0; i < lenof(hostkey_algs); i++) {
+ ssh2_pkt_addstring_str(s->pktout, hostkey_algs[i]->name);
+ if (i < lenof(hostkey_algs) - 1)
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ }
+ /* List client->server encryption algorithms. */
+ ssh2_pkt_addstring_start(s->pktout);
+ cipherstr_started = 0;
+ for (i = 0; i < s->n_preferred_ciphers; i++) {
+ const struct ssh2_ciphers *c = s->preferred_ciphers[i];
+ if (!c) continue; /* warning flag */
+ for (j = 0; j < c->nciphers; j++) {
+ if (cipherstr_started)
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
+ cipherstr_started = 1;
+ }
+ }
+ /* List server->client encryption algorithms. */
+ ssh2_pkt_addstring_start(s->pktout);
+ cipherstr_started = 0;
+ for (i = 0; i < s->n_preferred_ciphers; i++) {
+ const struct ssh2_ciphers *c = s->preferred_ciphers[i];
+ if (!c) continue; /* warning flag */
+ for (j = 0; j < c->nciphers; j++) {
+ if (cipherstr_started)
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
+ cipherstr_started = 1;
+ }
+ }
+ /* List client->server MAC algorithms. */
+ ssh2_pkt_addstring_start(s->pktout);
+ for (i = 0; i < s->nmacs; i++) {
+ ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
+ if (i < s->nmacs - 1)
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ }
+ /* List server->client MAC algorithms. */
+ ssh2_pkt_addstring_start(s->pktout);
+ for (i = 0; i < s->nmacs; i++) {
+ ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
+ if (i < s->nmacs - 1)
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ }
+ /* List client->server compression algorithms. */
+ ssh2_pkt_addstring_start(s->pktout);
+ assert(lenof(compressions) > 1);
+ ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
+ for (i = 0; i < lenof(compressions); i++) {
+ const struct ssh_compress *c = compressions[i];
+ if (c != s->preferred_comp) {
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ ssh2_pkt_addstring_str(s->pktout, c->name);
+ }
+ }
+ /* List server->client compression algorithms. */
+ ssh2_pkt_addstring_start(s->pktout);
+ assert(lenof(compressions) > 1);
+ ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
+ for (i = 0; i < lenof(compressions); i++) {
+ const struct ssh_compress *c = compressions[i];
+ if (c != s->preferred_comp) {
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ ssh2_pkt_addstring_str(s->pktout, c->name);
+ }
+ }
+ /* List client->server languages. Empty list. */
+ ssh2_pkt_addstring_start(s->pktout);
+ /* List server->client languages. Empty list. */
+ ssh2_pkt_addstring_start(s->pktout);
+ /* First KEX packet does _not_ follow, because we're not that brave. */
+ ssh2_pkt_addbool(s->pktout, FALSE);
+ /* Reserved. */
+ ssh2_pkt_adduint32(s->pktout, 0);
+ }
+
+ ssh->exhash = ssh->exhashbase;
+ sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
+
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+
+ if (!pktin)
+ crWaitUntil(pktin);
+ if (pktin->length > 5)
+ sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
+
+ /*
+ * Now examine the other side's KEXINIT to see what we're up
+ * to.
+ */
+ {
+ char *str;
+ int i, j, len;
+
+ if (pktin->type != SSH2_MSG_KEXINIT) {
+ bombout(("expected key exchange packet from server"));
+ crStop(0);
+ }
+ ssh->kex = NULL;
+ ssh->hostkey = NULL;
+ s->cscipher_tobe = NULL;
+ s->sccipher_tobe = NULL;
+ s->csmac_tobe = NULL;
+ s->scmac_tobe = NULL;
+ s->cscomp_tobe = NULL;
+ s->sccomp_tobe = NULL;
+ pktin->savedpos += 16; /* skip garbage cookie */
+ ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
+ for (i = 0; i < lenof(kex_algs); i++) {
+ if (kex_algs[i] == &ssh_diffiehellman_gex &&
+ (ssh->remote_bugs & BUG_SSH2_DH_GEX))
+ continue;
+ if (in_commasep_string(kex_algs[i]->name, str, len)) {
+ ssh->kex = kex_algs[i];
+ break;
+ }
+ }
+ ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
+ for (i = 0; i < lenof(hostkey_algs); i++) {
+ if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
+ ssh->hostkey = hostkey_algs[i];
+ break;
+ }
+ }
+ ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
+ s->warn = 0;
+ for (i = 0; i < s->n_preferred_ciphers; i++) {
+ const struct ssh2_ciphers *c = s->preferred_ciphers[i];
+ if (!c) {
+ s->warn = 1;
+ } else {
+ for (j = 0; j < c->nciphers; j++) {
+ if (in_commasep_string(c->list[j]->name, str, len)) {
+ s->cscipher_tobe = c->list[j];
+ break;
+ }
+ }
+ }
+ if (s->cscipher_tobe) {
+ if (s->warn)
+ askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
+ break;
+ }
+ }
+ if (!s->cscipher_tobe) {
+ bombout(("Couldn't agree a client-to-server cipher (available: %s)",
+ str ? str : "(null)"));
+ crStop(0);
+ }
+
+ ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
+ s->warn = 0;
+ for (i = 0; i < s->n_preferred_ciphers; i++) {
+ const struct ssh2_ciphers *c = s->preferred_ciphers[i];
+ if (!c) {
+ s->warn = 1;
+ } else {
+ for (j = 0; j < c->nciphers; j++) {
+ if (in_commasep_string(c->list[j]->name, str, len)) {
+ s->sccipher_tobe = c->list[j];
+ break;
+ }
+ }
+ }
+ if (s->sccipher_tobe) {
+ if (s->warn)
+ askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
+ break;
+ }
+ }
+ if (!s->sccipher_tobe) {
+ bombout(("Couldn't agree a server-to-client cipher (available: %s)",
+ str ? str : "(null)"));
+ crStop(0);
+ }
+
+ ssh_pkt_getstring(pktin, &str, &len); /* client->server mac */
+ for (i = 0; i < s->nmacs; i++) {
+ if (in_commasep_string(s->maclist[i]->name, str, len)) {
+ s->csmac_tobe = s->maclist[i];
+ break;
+ }
+ }
+ ssh_pkt_getstring(pktin, &str, &len); /* server->client mac */
+ for (i = 0; i < s->nmacs; i++) {
+ if (in_commasep_string(s->maclist[i]->name, str, len)) {
+ s->scmac_tobe = s->maclist[i];
+ break;
+ }
+ }
+ ssh_pkt_getstring(pktin, &str, &len); /* client->server compression */
+ for (i = 0; i < lenof(compressions) + 1; i++) {
+ const struct ssh_compress *c =
+ i == 0 ? s->preferred_comp : compressions[i - 1];
+ if (in_commasep_string(c->name, str, len)) {
+ s->cscomp_tobe = c;
+ break;
+ }
+ }
+ ssh_pkt_getstring(pktin, &str, &len); /* server->client compression */
+ for (i = 0; i < lenof(compressions) + 1; i++) {
+ const struct ssh_compress *c =
+ i == 0 ? s->preferred_comp : compressions[i - 1];
+ if (in_commasep_string(c->name, str, len)) {
+ s->sccomp_tobe = c;
+ break;
+ }
+ }
+ }
+
+ /*
+ * Work out the number of bits of key we will need from the key
+ * exchange. We start with the maximum key length of either
+ * cipher...
+ */
+ {
+ int csbits, scbits;
+
+ csbits = s->cscipher_tobe->keylen;
+ scbits = s->sccipher_tobe->keylen;
+ s->nbits = (csbits > scbits ? csbits : scbits);
+ }
+ /* The keys only have 160-bit entropy, since they're based on
+ * a SHA-1 hash. So cap the key size at 160 bits. */
+ if (s->nbits > 160)
+ s->nbits = 160;
+
+ /*
+ * If we're doing Diffie-Hellman group exchange, start by
+ * requesting a group.
+ */
+ if (!ssh->kex->pdata) {
+ logevent("Doing Diffie-Hellman group exchange");
+ ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
+ /*
+ * Work out how big a DH group we will need to allow that
+ * much data.
+ */
+ s->pbits = 512 << ((s->nbits - 1) / 64);
+ s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
+ ssh2_pkt_adduint32(s->pktout, s->pbits);
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+
+ crWaitUntil(pktin);
+ if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
+ bombout(("expected key exchange group packet from server"));
+ crStop(0);
+ }
+ s->p = ssh2_pkt_getmp(pktin);
+ s->g = ssh2_pkt_getmp(pktin);
+ if (!s->p || !s->g) {
+ bombout(("unable to read mp-ints from incoming group packet"));
+ crStop(0);
+ }
+ ssh->kex_ctx = dh_setup_gex(s->p, s->g);
+ s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
+ s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
+ } else {
+ ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP;
+ ssh->kex_ctx = dh_setup_group(ssh->kex);
+ s->kex_init_value = SSH2_MSG_KEXDH_INIT;
+ s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
+ logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
+ ssh->kex->groupname);
+ }
+
+ logevent("Doing Diffie-Hellman key exchange");
+ /*
+ * Now generate and send e for Diffie-Hellman.
+ */
+ s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
+ s->pktout = ssh2_pkt_init(s->kex_init_value);
+ ssh2_pkt_addmp(s->pktout, s->e);
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+
+ crWaitUntil(pktin);
+ if (pktin->type != s->kex_reply_value) {
+ bombout(("expected key exchange reply packet from server"));
+ crStop(0);
+ }
+ ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
+ s->f = ssh2_pkt_getmp(pktin);
+ if (!s->f) {
+ bombout(("unable to parse key exchange reply packet"));
+ crStop(0);
+ }
+ ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
+
+ s->K = dh_find_K(ssh->kex_ctx, s->f);
+
+ sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
+ if (ssh->kex == &ssh_diffiehellman_gex) {
+ sha_uint32(&ssh->exhash, s->pbits);
+ sha_mpint(&ssh->exhash, s->p);
+ sha_mpint(&ssh->exhash, s->g);
+ }
+ sha_mpint(&ssh->exhash, s->e);
+ sha_mpint(&ssh->exhash, s->f);
+ sha_mpint(&ssh->exhash, s->K);
+ SHA_Final(&ssh->exhash, s->exchange_hash);
+
+ dh_cleanup(ssh->kex_ctx);
+ ssh->kex_ctx = NULL;
+
+#if 0
+ debug(("Exchange hash is:\n"));
+ dmemdump(s->exchange_hash, 20);
+#endif
+
+ s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
+ if (!s->hkey ||
+ !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
+ (char *)s->exchange_hash, 20)) {
+ bombout(("Server's host key did not match the signature supplied"));
+ crStop(0);
+ }
+
+ /*
+ * Authenticate remote host: verify host key. (We've already
+ * checked the signature of the exchange hash.)
+ */
+ s->keystr = ssh->hostkey->fmtkey(s->hkey);
+ s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
+ verify_ssh_host_key(ssh->frontend,
+ ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
+ s->keystr, s->fingerprint);
+ if (s->first_kex) { /* don't bother logging this in rekeys */
+ logevent("Host key fingerprint is:");
+ logevent(s->fingerprint);
+ }
+ sfree(s->fingerprint);
+ sfree(s->keystr);
+ ssh->hostkey->freekey(s->hkey);
+
+ /*
+ * The exchange hash from the very first key exchange is also
+ * the session id, used in session key construction and
+ * authentication.
+ */
+ if (s->first_kex)
+ memcpy(ssh->v2_session_id, s->exchange_hash,
+ sizeof(s->exchange_hash));
+
+ /*
+ * Send SSH2_MSG_NEWKEYS.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_NEWKEYS);
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+ ssh->outgoing_data_size = 0; /* start counting from here */
+
+ /*
+ * We've sent client NEWKEYS, so create and initialise
+ * client-to-server session keys.
+ */
+ if (ssh->cs_cipher_ctx)
+ ssh->cscipher->free_context(ssh->cs_cipher_ctx);
+ ssh->cscipher = s->cscipher_tobe;
+ ssh->cs_cipher_ctx = ssh->cscipher->make_context();
+
+ if (ssh->cs_mac_ctx)
+ ssh->csmac->free_context(ssh->cs_mac_ctx);
+ ssh->csmac = s->csmac_tobe;
+ ssh->cs_mac_ctx = ssh->csmac->make_context();
+
+ if (ssh->cs_comp_ctx)
+ ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
+ ssh->cscomp = s->cscomp_tobe;
+ ssh->cs_comp_ctx = ssh->cscomp->compress_init();
+
+ /*
+ * Set IVs on client-to-server keys. Here we use the exchange
+ * hash from the _first_ key exchange.
+ */
+ {
+ unsigned char keyspace[40];
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
+ ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
+ ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
+ ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
+ }
+
+ logeventf(ssh, "Initialised %.200s client->server encryption",
+ ssh->cscipher->text_name);
+ logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
+ ssh->csmac->text_name);
+ if (ssh->cscomp->text_name)
+ logeventf(ssh, "Initialised %s compression",
+ ssh->cscomp->text_name);
+
+ /*
+ * Now our end of the key exchange is complete, we can send all
+ * our queued higher-layer packets.
+ */
+ ssh->queueing = FALSE;
+ ssh2_pkt_queuesend(ssh);
+
+ /*
+ * Expect SSH2_MSG_NEWKEYS from server.
+ */
+ crWaitUntil(pktin);
+ if (pktin->type != SSH2_MSG_NEWKEYS) {
+ bombout(("expected new-keys packet from server"));
+ crStop(0);
+ }
+ ssh->incoming_data_size = 0; /* start counting from here */
+
+ /*
+ * We've seen server NEWKEYS, so create and initialise
+ * server-to-client session keys.
+ */
+ if (ssh->sc_cipher_ctx)
+ ssh->sccipher->free_context(ssh->sc_cipher_ctx);
+ ssh->sccipher = s->sccipher_tobe;
+ ssh->sc_cipher_ctx = ssh->sccipher->make_context();
+
+ if (ssh->sc_mac_ctx)
+ ssh->scmac->free_context(ssh->sc_mac_ctx);
+ ssh->scmac = s->scmac_tobe;
+ ssh->sc_mac_ctx = ssh->scmac->make_context();
+
+ if (ssh->sc_comp_ctx)
+ ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
+ ssh->sccomp = s->sccomp_tobe;
+ ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
+
+ /*
+ * Set IVs on server-to-client keys. Here we use the exchange
+ * hash from the _first_ key exchange.
+ */
+ {
+ unsigned char keyspace[40];
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
+ ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
+ ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
+ ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
+ }
+ logeventf(ssh, "Initialised %.200s server->client encryption",
+ ssh->sccipher->text_name);
+ logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
+ ssh->scmac->text_name);
+ if (ssh->sccomp->text_name)
+ logeventf(ssh, "Initialised %s decompression",
+ ssh->sccomp->text_name);
+
+ /*
+ * Free key exchange data.
+ */
+ freebn(s->f);
+ freebn(s->K);
+ if (ssh->kex == &ssh_diffiehellman_gex) {
+ freebn(s->g);
+ freebn(s->p);
+ }
+
+ /*
+ * Key exchange is over. Schedule a timer for our next rekey.
+ */
+ ssh->kex_in_progress = FALSE;
+ ssh->next_rekey = schedule_timer(REKEY_TIMEOUT, ssh2_timer, ssh);
+
+ /*
+ * If this is the first key exchange phase, we must pass the
+ * SSH2_MSG_NEWKEYS packet to the next layer, not because it
+ * wants to see it but because it will need time to initialise
+ * itself before it sees an actual packet. In subsequent key
+ * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
+ * it would only confuse the layer above.
+ */
+ if (!s->first_kex) {
+ crReturn(1);
+ }
+ s->first_kex = 0;
+
+ /*
+ * Now we're encrypting. Begin returning 1 to the protocol main
+ * function so that other things can run on top of the
+ * transport. If we ever see a KEXINIT, we must go back to the
+ * start.
+ *
+ * We _also_ go back to the start if we see pktin==NULL and
+ * inlen==-1, because this is a special signal meaning
+ * `initiate client-driven rekey', and `in' contains a message
+ * giving the reason for the rekey.
+ */
+ while (!((pktin && pktin->type == SSH2_MSG_KEXINIT) ||
+ (!pktin && inlen == -1))) {
+ crReturn(1);
+ }
+ if (pktin) {
+ logevent("Server initiated key re-exchange");
+ } else {
+ logevent((char *)in);
+ }
+ goto begin_key_exchange;
+
+ crFinish(1);
+}
+
+/*
+ * Add data to an SSH2 channel output buffer.
+ */
+static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
+ int len)
+{
+ bufchain_add(&c->v.v2.outbuffer, buf, len);
+}
+
+/*
+ * Attempt to send data on an SSH2 channel.
+ */
+static int ssh2_try_send(struct ssh_channel *c)
+{
+ Ssh ssh = c->ssh;
+ struct Packet *pktout;
+
+ while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
+ int len;
+ void *data;
+ bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
+ if ((unsigned)len > c->v.v2.remwindow)
+ len = c->v.v2.remwindow;
+ if ((unsigned)len > c->v.v2.remmaxpkt)
+ len = c->v.v2.remmaxpkt;
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ dont_log_data(ssh, pktout, PKTLOG_OMIT);
+ ssh2_pkt_addstring_start(pktout);
+ ssh2_pkt_addstring_data(pktout, data, len);
+ end_log_omission(ssh, pktout);
+ ssh2_pkt_send(ssh, pktout);
+ bufchain_consume(&c->v.v2.outbuffer, len);
+ c->v.v2.remwindow -= len;
+ }
+
+ /*
+ * After having sent as much data as we can, return the amount
+ * still buffered.
+ */
+ return bufchain_size(&c->v.v2.outbuffer);
+}
+
+/*
+ * Potentially enlarge the window on an SSH2 channel.
+ */
+static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
+{
+ Ssh ssh = c->ssh;
+
+ /*
+ * Never send WINDOW_ADJUST for a channel that the remote side
+ * already thinks it's closed; there's no point, since it won't
+ * be sending any more data anyway.
+ */
+ if (c->closes != 0)
+ return;
+
+ if (newwin > c->v.v2.locwindow) {
+ struct Packet *pktout;
+
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
+ ssh2_pkt_send(ssh, pktout);
+ c->v.v2.locwindow = newwin;
+ }
+}
+
+static void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (c && !c->closes)
+ c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
+}
+
+static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
+{
+ char *data;
+ int length;
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+ if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
+ ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
+ return; /* extended but not stderr */
+ ssh_pkt_getstring(pktin, &data, &length);
+ if (data) {
+ int bufsize = 0;
+ c->v.v2.locwindow -= length;
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ bufsize =
+ from_backend(ssh->frontend, pktin->type ==
+ SSH2_MSG_CHANNEL_EXTENDED_DATA,
+ data, length);
+ break;
+ case CHAN_X11:
+ bufsize = x11_send(c->u.x11.s, data, length);
+ break;
+ case CHAN_SOCKDATA:
+ bufsize = pfd_send(c->u.pfd.s, data, length);
+ break;
+ case CHAN_AGENT:
+ while (length > 0) {
+ if (c->u.a.lensofar < 4) {
+ int l = min(4 - c->u.a.lensofar, length);
+ memcpy(c->u.a.msglen + c->u.a.lensofar,
+ data, l);
+ data += l;
+ length -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == 4) {
+ c->u.a.totallen =
+ 4 + GET_32BIT(c->u.a.msglen);
+ c->u.a.message = snewn(c->u.a.totallen,
+ unsigned char);
+ memcpy(c->u.a.message, c->u.a.msglen, 4);
+ }
+ if (c->u.a.lensofar >= 4 && length > 0) {
+ int l =
+ min(c->u.a.totallen - c->u.a.lensofar,
+ length);
+ memcpy(c->u.a.message + c->u.a.lensofar,
+ data, l);
+ data += l;
+ length -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == c->u.a.totallen) {
+ void *reply;
+ int replylen;
+ if (agent_query(c->u.a.message,
+ c->u.a.totallen,
+ &reply, &replylen,
+ ssh_agentf_callback, c))
+ ssh_agentf_callback(c, reply, replylen);
+ sfree(c->u.a.message);
+ c->u.a.lensofar = 0;
+ }
+ }
+ bufsize = 0;
+ break;
+ }
+ /*
+ * If we are not buffering too much data,
+ * enlarge the window again at the remote side.
+ */
+ if (bufsize < OUR_V2_WINSIZE)
+ ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
+ }
+}
+
+static void ssh2_msg_channel_eof(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+
+ if (c->type == CHAN_X11) {
+ /*
+ * Remote EOF on an X11 channel means we should
+ * wrap up and close the channel ourselves.
+ */
+ x11_close(c->u.x11.s);
+ sshfwd_close(c);
+ } else if (c->type == CHAN_AGENT) {
+ sshfwd_close(c);
+ } else if (c->type == CHAN_SOCKDATA) {
+ pfd_close(c->u.pfd.s);
+ sshfwd_close(c);
+ }
+}
+
+static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ struct Packet *pktout;
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c || ((int)c->remoteid) == -1) {
+ bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
+ c ? "half-open" : "nonexistent", i));
+ return;
+ }
+ /* Do pre-close processing on the channel. */
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ ssh->mainchan = NULL;
+ update_specials_menu(ssh->frontend);
+ break;
+ case CHAN_X11:
+ if (c->u.x11.s != NULL)
+ x11_close(c->u.x11.s);
+ sshfwd_close(c);
+ break;
+ case CHAN_AGENT:
+ sshfwd_close(c);
+ break;
+ case CHAN_SOCKDATA:
+ if (c->u.pfd.s != NULL)
+ pfd_close(c->u.pfd.s);
+ sshfwd_close(c);
+ break;
+ }
+ if (c->closes == 0) {
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+ del234(ssh->channels, c);
+ bufchain_clear(&c->v.v2.outbuffer);
+ sfree(c);
+
+ /*
+ * See if that was the last channel left open.
+ * (This is only our termination condition if we're
+ * not running in -N mode.)
+ */
+ if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
+ logevent("All channels closed. Disconnecting");
+#if 0
+ /*
+ * We used to send SSH_MSG_DISCONNECT here,
+ * because I'd believed that _every_ conforming
+ * SSH2 connection had to end with a disconnect
+ * being sent by at least one side; apparently
+ * I was wrong and it's perfectly OK to
+ * unceremoniously slam the connection shut
+ * when you're done, and indeed OpenSSH feels
+ * this is more polite than sending a
+ * DISCONNECT. So now we don't.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
+ ssh2_pkt_addstring(s->pktout, "All open channels closed");
+ ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+#endif
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ }
+}
+
+static void ssh2_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ struct Packet *pktout;
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+ if (c->type != CHAN_SOCKDATA_DORMANT)
+ return; /* dunno why they're confirming this */
+ c->remoteid = ssh_pkt_getuint32(pktin);
+ c->type = CHAN_SOCKDATA;
+ c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
+ c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
+ if (c->u.pfd.s)
+ pfd_confirm(c->u.pfd.s);
+ if (c->closes) {
+ /*
+ * We have a pending close on this channel,
+ * which we decided on before the server acked
+ * the channel open. So now we know the
+ * remoteid, we can close it again.
+ */
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
+static void ssh2_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
+{
+ static const char *const reasons[] = {
+ "<unknown reason code>",
+ "Administratively prohibited",
+ "Connect failed",
+ "Unknown channel type",
+ "Resource shortage",
+ };
+ unsigned i = ssh_pkt_getuint32(pktin);
+ unsigned reason_code;
+ char *reason_string;
+ int reason_length;
+ char *message;
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+ if (c->type != CHAN_SOCKDATA_DORMANT)
+ return; /* dunno why they're failing this */
+
+ reason_code = ssh_pkt_getuint32(pktin);
+ if (reason_code >= lenof(reasons))
+ reason_code = 0; /* ensure reasons[reason_code] in range */
+ ssh_pkt_getstring(pktin, &reason_string, &reason_length);
+ message = dupprintf("Forwarded connection refused by"
+ " server: %s [%.*s]", reasons[reason_code],
+ reason_length, reason_string);
+ logevent(message);
+ sfree(message);
+
+ pfd_close(c->u.pfd.s);
+
+ del234(ssh->channels, c);
+ sfree(c);
+}
+
+static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin)
+{
+ unsigned localid;
+ char *type;
+ int typelen, want_reply;
+ int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
+ struct ssh_channel *c;
+ struct Packet *pktout;
+
+ localid = ssh_pkt_getuint32(pktin);
+ ssh_pkt_getstring(pktin, &type, &typelen);
+ want_reply = ssh2_pkt_getbool(pktin);
+
+ /*
+ * First, check that the channel exists. Otherwise,
+ * we can instantly disconnect with a rude message.
+ */
+ c = find234(ssh->channels, &localid, ssh_channelfind);
+ if (!c) {
+ char buf[80];
+ sprintf(buf, "Received channel request for nonexistent"
+ " channel %d", localid);
+ logevent(buf);
+ pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
+ ssh2_pkt_addstring(pktout, buf);
+ ssh2_pkt_addstring(pktout, "en"); /* language tag */
+ ssh2_pkt_send_noqueue(ssh, pktout);
+ connection_fatal(ssh->frontend, "%s", buf);
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ return;
+ }
+
+ /*
+ * Having got the channel number, we now look at
+ * the request type string to see if it's something
+ * we recognise.
+ */
+ if (c == ssh->mainchan) {
+ /*
+ * We recognise "exit-status" and "exit-signal" on
+ * the primary channel.
+ */
+ if (typelen == 11 &&
+ !memcmp(type, "exit-status", 11)) {
+
+ ssh->exitcode = ssh_pkt_getuint32(pktin);
+ logeventf(ssh, "Server sent command exit status %d",
+ ssh->exitcode);
+ reply = SSH2_MSG_CHANNEL_SUCCESS;
+
+ } else if (typelen == 11 &&
+ !memcmp(type, "exit-signal", 11)) {
+
+ int is_plausible = TRUE, is_int = FALSE;
+ char *fmt_sig = "", *fmt_msg = "";
+ char *msg;
+ int msglen = 0, core = FALSE;
+ /* ICK: older versions of OpenSSH (e.g. 3.4p1)
+ * provide an `int' for the signal, despite its
+ * having been a `string' in the drafts since at
+ * least 2001. (Fixed in session.c 1.147.) Try to
+ * infer which we can safely parse it as. */
+ {
+ unsigned char *p = pktin->body +
+ pktin->savedpos;
+ long len = pktin->length - pktin->savedpos;
+ unsigned long num = GET_32BIT(p); /* what is it? */
+ /* If it's 0, it hardly matters; assume string */
+ if (num == 0) {
+ is_int = FALSE;
+ } else {
+ int maybe_int = FALSE, maybe_str = FALSE;
+#define CHECK_HYPOTHESIS(offset, result) \
+ do { \
+ long q = offset; \
+ if (q >= 0 && q+4 <= len) { \
+ q = q + 4 + GET_32BIT(p+q); \
+ if (q >= 0 && q+4 <= len && \
+ (q = q + 4 + GET_32BIT(p+q)) && q == len) \
+ result = TRUE; \
+ } \
+ } while(0)
+ CHECK_HYPOTHESIS(4+1, maybe_int);
+ CHECK_HYPOTHESIS(4+num+1, maybe_str);
+#undef CHECK_HYPOTHESIS
+ if (maybe_int && !maybe_str)
+ is_int = TRUE;
+ else if (!maybe_int && maybe_str)
+ is_int = FALSE;
+ else
+ /* Crikey. Either or neither. Panic. */
+ is_plausible = FALSE;
+ }
+ }
+ if (is_plausible) {
+ if (is_int) {
+ /* Old non-standard OpenSSH. */
+ int signum = ssh_pkt_getuint32(pktin);
+ fmt_sig = dupprintf(" %d", signum);
+ } else {
+ /* As per the drafts. */
+ char *sig;
+ int siglen;
+ ssh_pkt_getstring(pktin, &sig, &siglen);
+ /* Signal name isn't supposed to be blank, but
+ * let's cope gracefully if it is. */
+ if (siglen) {
+ fmt_sig = dupprintf(" \"%.*s\"",
+ siglen, sig);
+ }
+ }
+ core = ssh2_pkt_getbool(pktin);
+ ssh_pkt_getstring(pktin, &msg, &msglen);
+ if (msglen) {
+ fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
+ }
+ /* ignore lang tag */
+ } /* else don't attempt to parse */
+ logeventf(ssh, "Server exited on signal%s%s%s",
+ fmt_sig, core ? " (core dumped)" : "",
+ fmt_msg);
+ if (*fmt_sig) sfree(fmt_sig);
+ if (*fmt_msg) sfree(fmt_msg);
+ reply = SSH2_MSG_CHANNEL_SUCCESS;
+
+ }
+ } else {
+ /*
+ * This is a channel request we don't know
+ * about, so we now either ignore the request
+ * or respond with CHANNEL_FAILURE, depending
+ * on want_reply.
+ */
+ reply = SSH2_MSG_CHANNEL_FAILURE;
+ }
+ if (want_reply) {
+ pktout = ssh2_pkt_init(reply);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
+static void ssh2_msg_global_request(Ssh ssh, struct Packet *pktin)
+{
+ char *type;
+ int typelen, want_reply;
+ struct Packet *pktout;
+
+ ssh_pkt_getstring(pktin, &type, &typelen);
+ want_reply = ssh2_pkt_getbool(pktin);
+
+ /*
+ * We currently don't support any global requests
+ * at all, so we either ignore the request or
+ * respond with REQUEST_FAILURE, depending on
+ * want_reply.
+ */
+ if (want_reply) {
+ pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
+static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
+{
+ char *type;
+ int typelen;
+ char *peeraddr;
+ int peeraddrlen;
+ int peerport;
+ char *error = NULL;
+ struct ssh_channel *c;
+ unsigned remid, winsize, pktsize;
+ struct Packet *pktout;
+
+ ssh_pkt_getstring(pktin, &type, &typelen);
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+
+ remid = ssh_pkt_getuint32(pktin);
+ winsize = ssh_pkt_getuint32(pktin);
+ pktsize = ssh_pkt_getuint32(pktin);
+
+ if (typelen == 3 && !memcmp(type, "x11", 3)) {
+ char *addrstr;
+
+ ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
+ addrstr = snewn(peeraddrlen+1, char);
+ memcpy(addrstr, peeraddr, peeraddrlen);
+ addrstr[peeraddrlen] = '\0';
+ peerport = ssh_pkt_getuint32(pktin);
+
+ logeventf(ssh, "Received X11 connect request from %s:%d",
+ addrstr, peerport);
+
+ if (!ssh->X11_fwd_enabled)
+ error = "X11 forwarding is not enabled";
+ else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
+ ssh->x11auth, addrstr, peerport,
+ &ssh->cfg) != NULL) {
+ error = "Unable to open an X11 connection";
+ } else {
+ logevent("Opening X11 forward connection succeeded");
+ c->type = CHAN_X11;
+ }
+
+ sfree(addrstr);
+ } else if (typelen == 15 &&
+ !memcmp(type, "forwarded-tcpip", 15)) {
+ struct ssh_rportfwd pf, *realpf;
+ char *dummy;
+ int dummylen;
+ ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
+ pf.sport = ssh_pkt_getuint32(pktin);
+ ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
+ peerport = ssh_pkt_getuint32(pktin);
+ realpf = find234(ssh->rportfwds, &pf, NULL);
+ logeventf(ssh, "Received remote port %d open request "
+ "from %s:%d", pf.sport, peeraddr, peerport);
+ if (realpf == NULL) {
+ error = "Remote port is not recognised";
+ } else {
+ const char *e = pfd_newconnect(&c->u.pfd.s,
+ realpf->dhost,
+ realpf->dport, c,
+ &ssh->cfg);
+ logeventf(ssh, "Attempting to forward remote port to "
+ "%s:%d", realpf->dhost, realpf->dport);
+ if (e != NULL) {
+ logeventf(ssh, "Port open failed: %s", e);
+ error = "Port open failed";
+ } else {
+ logevent("Forwarded port opened successfully");
+ c->type = CHAN_SOCKDATA;
+ }
+ }
+ } else if (typelen == 22 &&
+ !memcmp(type, "auth-agent@openssh.com", 3)) {
+ if (!ssh->agentfwd_enabled)
+ error = "Agent forwarding is not enabled";
+ else {
+ c->type = CHAN_AGENT; /* identify channel type */
+ c->u.a.lensofar = 0;
+ }
+ } else {
+ error = "Unsupported channel type requested";
+ }
+
+ c->remoteid = remid;
+ if (error) {
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_adduint32(pktout, SSH2_OPEN_CONNECT_FAILED);
+ ssh2_pkt_addstring(pktout, error);
+ ssh2_pkt_addstring(pktout, "en"); /* language tag */
+ ssh2_pkt_send(ssh, pktout);
+ logeventf(ssh, "Rejected channel open: %s", error);
+ sfree(c);
+ } else {
+ c->localid = alloc_channel_id(ssh);
+ c->closes = 0;
+ c->v.v2.locwindow = OUR_V2_WINSIZE;
+ c->v.v2.remwindow = winsize;
+ c->v.v2.remmaxpkt = pktsize;
+ bufchain_init(&c->v.v2.outbuffer);
+ add234(ssh->channels, c);
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_adduint32(pktout, c->localid);
+ ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
+ ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
+/*
+ * Handle the SSH2 userauth and connection layers.
+ */
+static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
+ struct Packet *pktin)
+{
+ struct do_ssh2_authconn_state {
+ enum {
+ AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
+ AUTH_PASSWORD,
+ AUTH_KEYBOARD_INTERACTIVE
+ } method;
+ enum {
+ AUTH_TYPE_NONE,
+ AUTH_TYPE_PUBLICKEY,
+ AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
+ AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
+ AUTH_TYPE_PASSWORD,
+ AUTH_TYPE_KEYBOARD_INTERACTIVE,
+ AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
+ } type;
+ int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
+ int tried_pubkey_config, tried_agent, tried_keyb_inter;
+ int kbd_inter_running;
+ int we_are_in;
+ int num_prompts, curr_prompt, echo;
+ char username[100];
+ int got_username;
+ char pwprompt[512];
+ char password[100];
+ void *publickey_blob;
+ int publickey_bloblen;
+ unsigned char request[5], *response, *p;
+ int responselen;
+ int keyi, nkeys;
+ int authed;
+ char *pkblob, *alg, *commentp;
+ int pklen, alglen, commentlen;
+ int siglen, retlen, len;
+ char *q, *agentreq, *ret;
+ int try_send;
+ int num_env, env_left, env_ok;
+ struct Packet *pktout;
+ };
+ crState(do_ssh2_authconn_state);
+
+ crBegin(ssh->do_ssh2_authconn_crstate);
+
+ /*
+ * Request userauth protocol, and await a response to it.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
+ ssh2_pkt_addstring(s->pktout, "ssh-userauth");
+ ssh2_pkt_send(ssh, s->pktout);
+ crWaitUntilV(pktin);
+ if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
+ bombout(("Server refused user authentication protocol"));
+ crStopV;
+ }
+
+ /*
+ * We repeat this whole loop, including the username prompt,
+ * until we manage a successful authentication. If the user
+ * types the wrong _password_, they can be sent back to the
+ * beginning to try another username, if this is configured on.
+ * (If they specify a username in the config, they are never
+ * asked, even if they do give a wrong password.)
+ *
+ * I think this best serves the needs of
+ *
+ * - the people who have no configuration, no keys, and just
+ * want to try repeated (username,password) pairs until they
+ * type both correctly
+ *
+ * - people who have keys and configuration but occasionally
+ * need to fall back to passwords
+ *
+ * - people with a key held in Pageant, who might not have
+ * logged in to a particular machine before; so they want to
+ * type a username, and then _either_ their key will be
+ * accepted, _or_ they will type a password. If they mistype
+ * the username they will want to be able to get back and
+ * retype it!
+ */
+ s->username[0] = '\0';
+ s->got_username = FALSE;
+ do {
+ /*
+ * Get a username.
+ */
+ if (s->got_username && !ssh->cfg.change_username) {
+ /*
+ * We got a username last time round this loop, and
+ * with change_username turned off we don't try to get
+ * it again.
+ */
+ } else if (!*ssh->cfg.username) {
+ if (ssh_get_line && !ssh_getline_pw_only) {
+ if (!ssh_get_line("login as: ",
+ s->username, sizeof(s->username), FALSE)) {
+ /*
+ * get_line failed to get a username.
+ * Terminate.
+ */
+ logevent("No username provided. Abandoning session.");
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ crStopV;
+ }
+ } else {
+ int ret; /* need not be saved across crReturn */
+ c_write_str(ssh, "login as: ");
+ ssh->send_ok = 1;
+ setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
+ do {
+ crWaitUntilV(!pktin);
+ ret = process_userpass_input(ssh, in, inlen);
+ } while (ret == 0);
+ if (ret < 0)
+ cleanup_exit(0);
+ c_write_str(ssh, "\r\n");
+ }
+ s->username[strcspn(s->username, "\n\r")] = '\0';
+ } else {
+ char *stuff;
+ strncpy(s->username, ssh->cfg.username, sizeof(s->username));
+ s->username[sizeof(s->username)-1] = '\0';
+ if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
+ stuff = dupprintf("Using username \"%s\".\r\n", s->username);
+ c_write_str(ssh, stuff);
+ sfree(stuff);
+ }
+ }
+ s->got_username = TRUE;
+
+ /*
+ * Send an authentication request using method "none": (a)
+ * just in case it succeeds, and (b) so that we know what
+ * authentication methods we can usefully try next.
+ */
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");/* service requested */
+ ssh2_pkt_addstring(s->pktout, "none"); /* method */
+ ssh2_pkt_send(ssh, s->pktout);
+ s->type = AUTH_TYPE_NONE;
+ s->gotit = FALSE;
+ s->we_are_in = FALSE;
+
+ s->tried_pubkey_config = FALSE;
+ s->tried_agent = FALSE;
+ s->tried_keyb_inter = FALSE;
+ s->kbd_inter_running = FALSE;
+ /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
+ if (!filename_is_null(ssh->cfg.keyfile)) {
+ int keytype;
+ logeventf(ssh, "Reading private key file \"%.150s\"",
+ filename_to_str(&ssh->cfg.keyfile));
+ keytype = key_type(&ssh->cfg.keyfile);
+ if (keytype == SSH_KEYTYPE_SSH2) {
+ s->publickey_blob =
+ ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
+ &s->publickey_bloblen, NULL);
+ } else {
+ char *msgbuf;
+ logeventf(ssh, "Unable to use this key file (%s)",
+ key_type_to_str(keytype));
+ msgbuf = dupprintf("Unable to use key file \"%.150s\""
+ " (%s)\r\n",
+ filename_to_str(&ssh->cfg.keyfile),
+ key_type_to_str(keytype));
+ c_write_str(ssh, msgbuf);
+ sfree(msgbuf);
+ s->publickey_blob = NULL;
+ }
+ } else
+ s->publickey_blob = NULL;
+
+ while (1) {
+ /*
+ * Wait for the result of the last authentication request.
+ */
+ if (!s->gotit)
+ crWaitUntilV(pktin);
+ while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
+ char *banner;
+ int size;
+ /*
+ * Don't show the banner if we're operating in
+ * non-verbose non-interactive mode. (It's probably
+ * a script, which means nobody will read the
+ * banner _anyway_, and moreover the printing of
+ * the banner will screw up processing on the
+ * output of (say) plink.)
+ */
+ if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
+ ssh_pkt_getstring(pktin, &banner, &size);
+ if (banner)
+ c_write_untrusted(ssh, banner, size);
+ }
+ crWaitUntilV(pktin);
+ }
+ if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
+ logevent("Access granted");
+ s->we_are_in = TRUE;
+ break;
+ }
+
+ if (s->kbd_inter_running &&
+ pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
+ /*
+ * This is either a further set-of-prompts packet
+ * in keyboard-interactive authentication, or it's
+ * the same one and we came back here with `gotit'
+ * set. In the former case, we must reset the
+ * curr_prompt variable.
+ */
+ if (!s->gotit)
+ s->curr_prompt = 0;
+ } else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
+ bombout(("Strange packet received during authentication: type %d",
+ pktin->type));
+ crStopV;
+ }
+
+ s->gotit = FALSE;
+
+ /*
+ * OK, we're now sitting on a USERAUTH_FAILURE message, so
+ * we can look at the string in it and know what we can
+ * helpfully try next.
+ */
+ if (pktin->type == SSH2_MSG_USERAUTH_FAILURE) {
+ char *methods;
+ int methlen;
+ ssh_pkt_getstring(pktin, &methods, &methlen);
+ s->kbd_inter_running = FALSE;
+ if (!ssh2_pkt_getbool(pktin)) {
+ /*
+ * We have received an unequivocal Access
+ * Denied. This can translate to a variety of
+ * messages:
+ *
+ * - if we'd just tried "none" authentication,
+ * it's not worth printing anything at all
+ *
+ * - if we'd just tried a public key _offer_,
+ * the message should be "Server refused our
+ * key" (or no message at all if the key
+ * came from Pageant)
+ *
+ * - if we'd just tried anything else, the
+ * message really should be "Access denied".
+ *
+ * Additionally, if we'd just tried password
+ * authentication, we should break out of this
+ * whole loop so as to go back to the username
+ * prompt (iff we're configured to allow
+ * username change attempts).
+ */
+ if (s->type == AUTH_TYPE_NONE) {
+ /* do nothing */
+ } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
+ s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
+ if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
+ c_write_str(ssh, "Server refused our key\r\n");
+ logevent("Server refused public key");
+ } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
+ /* server declined keyboard-interactive; ignore */
+ } else {
+ c_write_str(ssh, "Access denied\r\n");
+ logevent("Access denied");
+ if (s->type == AUTH_TYPE_PASSWORD &&
+ ssh->cfg.change_username) {
+ /* XXX perhaps we should allow
+ * keyboard-interactive to do this too? */
+ s->we_are_in = FALSE;
+ break;
+ }
+ }
+ } else {
+ c_write_str(ssh, "Further authentication required\r\n");
+ logevent("Further authentication required");
+ }
+
+ s->can_pubkey =
+ in_commasep_string("publickey", methods, methlen);
+ s->can_passwd =
+ in_commasep_string("password", methods, methlen);
+ s->can_keyb_inter = ssh->cfg.try_ki_auth &&
+ in_commasep_string("keyboard-interactive", methods, methlen);
+ }
+
+ s->method = 0;
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ s->need_pw = FALSE;
+
+ /*
+ * Most password/passphrase prompts will be
+ * non-echoing, so we set this to 0 by default.
+ * Exception is that some keyboard-interactive prompts
+ * can be echoing, in which case we'll set this to 1.
+ */
+ s->echo = 0;
+
+ if (!s->method && s->can_pubkey &&
+ agent_exists() && !s->tried_agent) {
+ /*
+ * Attempt public-key authentication using Pageant.
+ */
+ void *r;
+ s->authed = FALSE;
+
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
+
+ s->tried_agent = TRUE;
+
+ logevent("Pageant is running. Requesting keys.");
+
+ /* Request the keys held by the agent. */
+ PUT_32BIT(s->request, 1);
+ s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
+ if (!agent_query(s->request, 5, &r, &s->responselen,
+ ssh_agent_callback, ssh)) {
+ do {
+ crReturnV;
+ if (pktin) {
+ bombout(("Unexpected data from server while"
+ " waiting for agent response"));
+ crStopV;
+ }
+ } while (pktin || inlen > 0);
+ r = ssh->agent_response;
+ s->responselen = ssh->agent_response_len;
+ }
+ s->response = (unsigned char *) r;
+ if (s->response && s->responselen >= 5 &&
+ s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
+ s->p = s->response + 5;
+ s->nkeys = GET_32BIT(s->p);
+ s->p += 4;
+ {
+ char buf[64];
+ sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
+ logevent(buf);
+ }
+ for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
+ void *vret;
+
+ {
+ char buf[64];
+ sprintf(buf, "Trying Pageant key #%d", s->keyi);
+ logevent(buf);
+ }
+ s->pklen = GET_32BIT(s->p);
+ s->p += 4;
+ if (s->publickey_blob &&
+ s->pklen == s->publickey_bloblen &&
+ !memcmp(s->p, s->publickey_blob,
+ s->publickey_bloblen)) {
+ logevent("This key matches configured key file");
+ s->tried_pubkey_config = 1;
+ }
+ s->pkblob = (char *)s->p;
+ s->p += s->pklen;
+ s->alglen = GET_32BIT(s->pkblob);
+ s->alg = s->pkblob + 4;
+ s->commentlen = GET_32BIT(s->p);
+ s->p += 4;
+ s->commentp = (char *)s->p;
+ s->p += s->commentlen;
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
+ ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
+ ssh2_pkt_send(ssh, s->pktout);
+
+ crWaitUntilV(pktin);
+ if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
+ logevent("Key refused");
+ continue;
+ }
+
+ if (flags & FLAG_VERBOSE) {
+ c_write_str(ssh, "Authenticating with "
+ "public key \"");
+ c_write(ssh, s->commentp, s->commentlen);
+ c_write_str(ssh, "\" from agent\r\n");
+ }
+
+ /*
+ * Server is willing to accept the key.
+ * Construct a SIGN_REQUEST.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
+ ssh2_pkt_addbool(s->pktout, TRUE);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
+
+ s->siglen = s->pktout->length - 5 + 4 + 20;
+ if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
+ s->siglen -= 4;
+ s->len = 1; /* message type */
+ s->len += 4 + s->pklen; /* key blob */
+ s->len += 4 + s->siglen; /* data to sign */
+ s->len += 4; /* flags */
+ s->agentreq = snewn(4 + s->len, char);
+ PUT_32BIT(s->agentreq, s->len);
+ s->q = s->agentreq + 4;
+ *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
+ PUT_32BIT(s->q, s->pklen);
+ s->q += 4;
+ memcpy(s->q, s->pkblob, s->pklen);
+ s->q += s->pklen;
+ PUT_32BIT(s->q, s->siglen);
+ s->q += 4;
+ /* Now the data to be signed... */
+ if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
+ PUT_32BIT(s->q, 20);
+ s->q += 4;
+ }
+ memcpy(s->q, ssh->v2_session_id, 20);
+ s->q += 20;
+ memcpy(s->q, s->pktout->data + 5,
+ s->pktout->length - 5);
+ s->q += s->pktout->length - 5;
+ /* And finally the (zero) flags word. */
+ PUT_32BIT(s->q, 0);
+ if (!agent_query(s->agentreq, s->len + 4,
+ &vret, &s->retlen,
+ ssh_agent_callback, ssh)) {
+ do {
+ crReturnV;
+ if (pktin) {
+ bombout(("Unexpected data from server"
+ " while waiting for agent"
+ " response"));
+ crStopV;
+ }
+ } while (pktin || inlen > 0);
+ vret = ssh->agent_response;
+ s->retlen = ssh->agent_response_len;
+ }
+ s->ret = vret;
+ sfree(s->agentreq);
+ if (s->ret) {
+ if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
+ logevent("Sending Pageant's response");
+ ssh2_add_sigblob(ssh, s->pktout,
+ s->pkblob, s->pklen,
+ s->ret + 9,
+ GET_32BIT(s->ret + 5));
+ ssh2_pkt_send(ssh, s->pktout);
+ s->authed = TRUE;
+ break;
+ } else {
+ logevent
+ ("Pageant failed to answer challenge");
+ sfree(s->ret);
+ }
+ }
+ }
+ if (s->authed)
+ continue;
+ }
+ sfree(s->response);
+ }
+
+ if (!s->method && s->can_pubkey && s->publickey_blob
+ && !s->tried_pubkey_config) {
+ unsigned char *pub_blob;
+ char *algorithm, *comment;
+ int pub_blob_len;
+
+ s->tried_pubkey_config = TRUE;
+
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
+
+ /*
+ * Try the public key supplied in the configuration.
+ *
+ * First, offer the public blob to see if the server is
+ * willing to accept it.
+ */
+ pub_blob =
+ (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
+ &algorithm,
+ &pub_blob_len,
+ NULL);
+ if (pub_blob) {
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
+ ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
+ ssh2_pkt_addstring(s->pktout, algorithm);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
+ pub_blob_len);
+ ssh2_pkt_send(ssh, s->pktout);
+ logevent("Offered public key");
+
+ crWaitUntilV(pktin);
+ if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
+ s->gotit = TRUE;
+ s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
+ continue; /* key refused; give up on it */
+ }
+
+ logevent("Offer of public key accepted");
+ /*
+ * Actually attempt a serious authentication using
+ * the key.
+ */
+ if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
+ sprintf(s->pwprompt,
+ "Passphrase for key \"%.100s\": ",
+ comment);
+ s->need_pw = TRUE;
+ } else {
+ s->need_pw = FALSE;
+ }
+ if (flags & FLAG_VERBOSE) {
+ c_write_str(ssh, "Authenticating with public key \"");
+ c_write_str(ssh, comment);
+ c_write_str(ssh, "\"\r\n");
+ }
+ s->method = AUTH_PUBLICKEY_FILE;
+ }
+ }
+
+ if (!s->method && s->can_keyb_inter && !s->tried_keyb_inter) {
+ s->method = AUTH_KEYBOARD_INTERACTIVE;
+ s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+ s->tried_keyb_inter = TRUE;
+
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
+
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
+ ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
+ ssh2_pkt_addstring(s->pktout, ""); /* lang */
+ ssh2_pkt_addstring(s->pktout, "");
+ ssh2_pkt_send(ssh, s->pktout);
+
+ crWaitUntilV(pktin);
+ if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
+ if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
+ s->gotit = TRUE;
+ logevent("Keyboard-interactive authentication refused");
+ s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
+ continue;
+ }
+
+ s->kbd_inter_running = TRUE;
+ s->curr_prompt = 0;
+ }
+
+ if (s->kbd_inter_running) {
+ s->method = AUTH_KEYBOARD_INTERACTIVE;
+ s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+ s->tried_keyb_inter = TRUE;
+
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
+
+ if (s->curr_prompt == 0) {
+ /*
+ * We've got a fresh USERAUTH_INFO_REQUEST.
+ * Display header data, and start going through
+ * the prompts.
+ */
+ char *name, *inst, *lang;
+ int name_len, inst_len, lang_len;
+
+ ssh_pkt_getstring(pktin, &name, &name_len);
+ ssh_pkt_getstring(pktin, &inst, &inst_len);
+ ssh_pkt_getstring(pktin, &lang, &lang_len);
+ if (name_len > 0) {
+ c_write_untrusted(ssh, name, name_len);
+ c_write_str(ssh, "\r\n");
+ }
+ if (inst_len > 0) {
+ c_write_untrusted(ssh, inst, inst_len);
+ c_write_str(ssh, "\r\n");
+ }
+ s->num_prompts = ssh_pkt_getuint32(pktin);
+ }
+
+ /*
+ * If there are prompts remaining in the packet,
+ * display one and get a response.
+ */
+ if (s->curr_prompt < s->num_prompts) {
+ char *prompt;
+ int prompt_len;
+
+ ssh_pkt_getstring(pktin, &prompt, &prompt_len);
+ if (prompt_len > 0) {
+ static const char trunc[] = "<prompt truncated>: ";
+ static const int prlen = sizeof(s->pwprompt) -
+ lenof(trunc);
+ if (prompt_len > prlen) {
+ memcpy(s->pwprompt, prompt, prlen);
+ strcpy(s->pwprompt + prlen, trunc);
+ } else {
+ memcpy(s->pwprompt, prompt, prompt_len);
+ s->pwprompt[prompt_len] = '\0';
+ }
+ } else {
+ strcpy(s->pwprompt,
+ "<server failed to send prompt>: ");
+ }
+ s->echo = ssh2_pkt_getbool(pktin);
+ s->need_pw = TRUE;
+ } else
+ s->need_pw = FALSE;
+ }
+
+ if (!s->method && s->can_passwd) {
+ s->method = AUTH_PASSWORD;
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
+ sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
+ ssh->savedhost);
+ s->need_pw = TRUE;
+ }
+
+ if (s->need_pw) {
+ if (ssh_get_line) {
+ if (!ssh_get_line(s->pwprompt, s->password,
+ sizeof(s->password), TRUE)) {
+ /*
+ * get_line failed to get a password (for
+ * example because one was supplied on the
+ * command line which has already failed to
+ * work). Terminate.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
+ ssh2_pkt_addstring(s->pktout, "No more passwords available"
+ " to try");
+ ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+ logevent("Unable to authenticate");
+ connection_fatal(ssh->frontend,
+ "Unable to authenticate");
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ crStopV;
+ }
+ } else {
+ int ret; /* need not be saved across crReturn */
+ c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
+ ssh->send_ok = 1;
+
+ setup_userpass_input(ssh, s->password,
+ sizeof(s->password), s->echo);
+ do {
+ crWaitUntilV(!pktin);
+ ret = process_userpass_input(ssh, in, inlen);
+ } while (ret == 0);
+ if (ret < 0)
+ cleanup_exit(0);
+ c_write_str(ssh, "\r\n");
+ }
+ }
+
+ if (s->method == AUTH_PUBLICKEY_FILE) {
+ /*
+ * We have our passphrase. Now try the actual authentication.
+ */
+ struct ssh2_userkey *key;
+ const char *error = NULL;
+
+ key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
+ &error);
+ if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
+ if (key == SSH2_WRONG_PASSPHRASE) {
+ c_write_str(ssh, "Wrong passphrase\r\n");
+ s->tried_pubkey_config = FALSE;
+ } else {
+ c_write_str(ssh, "Unable to load private key (");
+ c_write_str(ssh, error);
+ c_write_str(ssh, ")\r\n");
+ s->tried_pubkey_config = TRUE;
+ }
+ /* Send a spurious AUTH_NONE to return to the top. */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
+ ssh2_pkt_addstring(s->pktout, "none"); /* method */
+ ssh2_pkt_send(ssh, s->pktout);
+ s->type = AUTH_TYPE_NONE;
+ } else {
+ unsigned char *pkblob, *sigblob, *sigdata;
+ int pkblob_len, sigblob_len, sigdata_len;
+ int p;
+
+ /*
+ * We have loaded the private key and the server
+ * has announced that it's willing to accept it.
+ * Hallelujah. Generate a signature and send it.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
+ ssh2_pkt_addbool(s->pktout, TRUE);
+ ssh2_pkt_addstring(s->pktout, key->alg->name);
+ pkblob = key->alg->public_blob(key->data, &pkblob_len);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
+
+ /*
+ * The data to be signed is:
+ *
+ * string session-id
+ *
+ * followed by everything so far placed in the
+ * outgoing packet.
+ */
+ sigdata_len = s->pktout->length - 5 + 4 + 20;
+ if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
+ sigdata_len -= 4;
+ sigdata = snewn(sigdata_len, unsigned char);
+ p = 0;
+ if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
+ PUT_32BIT(sigdata+p, 20);
+ p += 4;
+ }
+ memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
+ memcpy(sigdata+p, s->pktout->data + 5,
+ s->pktout->length - 5);
+ p += s->pktout->length - 5;
+ assert(p == sigdata_len);
+ sigblob = key->alg->sign(key->data, (char *)sigdata,
+ sigdata_len, &sigblob_len);
+ ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
+ sigblob, sigblob_len);
+ sfree(pkblob);
+ sfree(sigblob);
+ sfree(sigdata);
+
+ ssh2_pkt_send(ssh, s->pktout);
+ s->type = AUTH_TYPE_PUBLICKEY;
+ key->alg->freekey(key->data);
+ }
+ } else if (s->method == AUTH_PASSWORD) {
+ /*
+ * We send the password packet lumped tightly together with
+ * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
+ * string long enough to make the total length of the two
+ * packets constant. This should ensure that a passive
+ * listener doing traffic analyis can't work out the length
+ * of the password.
+ *
+ * For this to work, we need an assumption about the
+ * maximum length of the password packet. I think 256 is
+ * pretty conservative. Anyone using a password longer than
+ * that probably doesn't have much to worry about from
+ * people who find out how long their password is!
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
+ ssh2_pkt_addstring(s->pktout, "password");
+ ssh2_pkt_addbool(s->pktout, FALSE);
+ dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
+ ssh2_pkt_addstring(s->pktout, s->password);
+ memset(s->password, 0, sizeof(s->password));
+ end_log_omission(ssh, s->pktout);
+ ssh2_pkt_defer(ssh, s->pktout);
+ /*
+ * We'll include a string that's an exact multiple of the
+ * cipher block size. If the cipher is NULL for some
+ * reason, we don't do this trick at all because we gain
+ * nothing by it.
+ */
+ if (ssh->cscipher) {
+ int stringlen, i;
+
+ stringlen = (256 - ssh->deferred_len);
+ stringlen += ssh->cscipher->blksize - 1;
+ stringlen -= (stringlen % ssh->cscipher->blksize);
+ if (ssh->cscomp) {
+ /*
+ * Temporarily disable actual compression,
+ * so we can guarantee to get this string
+ * exactly the length we want it. The
+ * compression-disabling routine should
+ * return an integer indicating how many
+ * bytes we should adjust our string length
+ * by.
+ */
+ stringlen -=
+ ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
+ }
+ s->pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
+ ssh2_pkt_addstring_start(s->pktout);
+ for (i = 0; i < stringlen; i++) {
+ char c = (char) random_byte();
+ ssh2_pkt_addstring_data(s->pktout, &c, 1);
+ }
+ ssh2_pkt_defer(ssh, s->pktout);
+ }
+ ssh_pkt_defersend(ssh);
+ logevent("Sent password");
+ s->type = AUTH_TYPE_PASSWORD;
+ } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
+ if (s->curr_prompt == 0) {
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
+ ssh2_pkt_adduint32(s->pktout, s->num_prompts);
+ }
+ if (s->need_pw) { /* only add pw if we just got one! */
+ dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
+ ssh2_pkt_addstring(s->pktout, s->password);
+ memset(s->password, 0, sizeof(s->password));
+ end_log_omission(ssh, s->pktout);
+ s->curr_prompt++;
+ }
+ if (s->curr_prompt >= s->num_prompts) {
+ ssh2_pkt_send(ssh, s->pktout);
+ } else {
+ /*
+ * If there are prompts remaining, we set
+ * `gotit' so that we won't attempt to get
+ * another packet. Then we go back round the
+ * loop and will end up retrieving another
+ * prompt out of the existing packet. Funky or
+ * what?
+ */
+ s->gotit = TRUE;
+ }
+ s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+ } else {
+ c_write_str(ssh, "No supported authentication methods"
+ " left to try!\r\n");
+ logevent("No supported authentications offered."
+ " Disconnecting");
+ s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
+ ssh2_pkt_addstring(s->pktout, "No supported authentication"
+ " methods available");
+ ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ crStopV;
+ }
+ }
+ } while (!s->we_are_in);
+
+ /*
+ * Now we're authenticated for the connection protocol. The
+ * connection protocol will automatically have started at this
+ * point; there's no need to send SERVICE_REQUEST.
+ */
+
+ ssh->channels = newtree234(ssh_channelcmp);
+
+ /*
+ * Set up handlers for some connection protocol messages, so we
+ * don't have to handle them repeatedly in this coroutine.
+ */
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
+ ssh2_msg_channel_window_adjust;
+ ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] =
+ ssh2_msg_global_request;
+
+ /*
+ * Create the main session channel.
+ */
+ if (!ssh->cfg.ssh_no_shell) {
+ ssh->mainchan = snew(struct ssh_channel);
+ ssh->mainchan->ssh = ssh;
+ ssh->mainchan->localid = alloc_channel_id(ssh);
+ s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
+ ssh2_pkt_addstring(s->pktout, "session");
+ ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
+ ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
+ ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
+ ssh2_pkt_adduint32(s->pktout, 0x4000UL); /* our max pkt size */
+ ssh2_pkt_send(ssh, s->pktout);
+ crWaitUntilV(pktin);
+ if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
+ bombout(("Server refused to open a session"));
+ crStopV;
+ /* FIXME: error data comes back in FAILURE packet */
+ }
+ if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) {
+ bombout(("Server's channel confirmation cited wrong channel"));
+ crStopV;
+ }
+ ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
+ ssh->mainchan->type = CHAN_MAINSESSION;
+ ssh->mainchan->closes = 0;
+ ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
+ ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
+ bufchain_init(&ssh->mainchan->v.v2.outbuffer);
+ add234(ssh->channels, ssh->mainchan);
+ update_specials_menu(ssh->frontend);
+ logevent("Opened channel for session");
+ } else
+ ssh->mainchan = NULL;
+
+ /*
+ * Now we have a channel, make dispatch table entries for
+ * general channel-based messages.
+ */
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] =
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] =
+ ssh2_msg_channel_data;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = ssh2_msg_channel_eof;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = ssh2_msg_channel_close;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] =
+ ssh2_msg_channel_open_confirmation;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] =
+ ssh2_msg_channel_open_failure;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] =
+ ssh2_msg_channel_request;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] =
+ ssh2_msg_channel_open;
+
+ /*
+ * Potentially enable X11 forwarding.
+ */
+ if (ssh->mainchan && ssh->cfg.x11_forward) {
+ char proto[20], data[64];
+ logevent("Requesting X11 forwarding");
+ ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
+ data, sizeof(data), ssh->cfg.x11_auth);
+ x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
+ s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
+ ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
+ ssh2_pkt_addstring(s->pktout, "x11-req");
+ ssh2_pkt_addbool(s->pktout, 1); /* want reply */
+ ssh2_pkt_addbool(s->pktout, 0); /* many connections */
+ ssh2_pkt_addstring(s->pktout, proto);
+ ssh2_pkt_addstring(s->pktout, data);
+ ssh2_pkt_adduint32(s->pktout, x11_get_screen_number(ssh->cfg.x11_display));
+ ssh2_pkt_send(ssh, s->pktout);
+
+ crWaitUntilV(pktin);
+
+ if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
+ if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
+ bombout(("Unexpected response to X11 forwarding request:"
+ " packet type %d", pktin->type));
+ crStopV;
+ }
+ logevent("X11 forwarding refused");
+ } else {
+ logevent("X11 forwarding enabled");
+ ssh->X11_fwd_enabled = TRUE;
+ }
+ }
+
+ /*
+ * Enable port forwardings.
+ */
+ {
+ char type;
+ int n;
+ int sport,dport,sserv,dserv;
+ char sports[256], dports[256], saddr[256], host[256];
+
+ ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
+ /* Add port forwardings. */
+ ssh->portfwd_strptr = ssh->cfg.portfwd;
+ while (*ssh->portfwd_strptr) {
+ type = *ssh->portfwd_strptr++;
+ saddr[0] = '\0';
+ n = 0;
+ while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
+ if (*ssh->portfwd_strptr == ':') {
+ /*
+ * We've seen a colon in the middle of the
+ * source port number. This means that
+ * everything we've seen until now is the
+ * source _address_, so we'll move it into
+ * saddr and start sports from the beginning
+ * again.
+ */
+ ssh->portfwd_strptr++;
+ sports[n] = '\0';
+ strcpy(saddr, sports);
+ n = 0;
+ }
+ if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
+ }
+ sports[n] = 0;
+ if (type != 'D') {
+ if (*ssh->portfwd_strptr == '\t')
+ ssh->portfwd_strptr++;
+ n = 0;
+ while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
+ if (n < 255) host[n++] = *ssh->portfwd_strptr++;
+ }
+ host[n] = 0;
+ if (*ssh->portfwd_strptr == ':')
+ ssh->portfwd_strptr++;
+ n = 0;
+ while (*ssh->portfwd_strptr) {
+ if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
+ }
+ dports[n] = 0;
+ ssh->portfwd_strptr++;
+ dport = atoi(dports);
+ dserv = 0;
+ if (dport == 0) {
+ dserv = 1;
+ dport = net_service_lookup(dports);
+ if (!dport) {
+ logeventf(ssh, "Service lookup failed for destination"
+ " port \"%s\"", dports);
+ }
+ }
+ } else {
+ while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
+ dport = dserv = -1;
+ ssh->portfwd_strptr++; /* eat the NUL and move to next one */
+ }
+ sport = atoi(sports);
+ sserv = 0;
+ if (sport == 0) {
+ sserv = 1;
+ sport = net_service_lookup(sports);
+ if (!sport) {
+ logeventf(ssh, "Service lookup failed for source"
+ " port \"%s\"", sports);
+ }
+ }
+ if (sport && dport) {
+ /* Set up a description of the source port. */
+ static char *sportdesc;
+ sportdesc = dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
+ (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
+ (int)(*saddr?1:0), ":",
+ (int)(sserv ? strlen(sports) : 0), sports,
+ sserv, "(", sport, sserv, ")");
+ if (type == 'L') {
+ /* Verbose description of the destination port */
+ char *dportdesc = dupprintf("%s:%.*s%.*s%d%.*s",
+ host,
+ (int)(dserv ? strlen(dports) : 0), dports,
+ dserv, "(", dport, dserv, ")");
+ const char *err = pfd_addforward(host, dport,
+ *saddr ? saddr : NULL,
+ sport, ssh, &ssh->cfg);
+ if (err) {
+ logeventf(ssh, "Local port %s forward to %s"
+ " failed: %s", sportdesc, dportdesc, err);
+ } else {
+ logeventf(ssh, "Local port %s forwarding to %s",
+ sportdesc, dportdesc);
+ }
+ sfree(dportdesc);
+ } else if (type == 'D') {
+ const char *err = pfd_addforward(NULL, -1,
+ *saddr ? saddr : NULL,
+ sport, ssh, &ssh->cfg);
+ if (err) {
+ logeventf(ssh, "Local port %s SOCKS dynamic forward"
+ " setup failed: %s", sportdesc, err);
+ } else {
+ logeventf(ssh, "Local port %s doing SOCKS"
+ " dynamic forwarding", sportdesc);
+ }
+ } else {
+ struct ssh_rportfwd *pf;
+ pf = snew(struct ssh_rportfwd);
+ strcpy(pf->dhost, host);
+ pf->dport = dport;
+ pf->sport = sport;
+ if (add234(ssh->rportfwds, pf) != pf) {
+ logeventf(ssh, "Duplicate remote port forwarding"
+ " to %s:%d", host, dport);
+ sfree(pf);
+ } else {
+ logeventf(ssh, "Requesting remote port %s"
+ " forward to %s:%.*s%.*s%d%.*s",
+ sportdesc,
+ host,
+ (int)(dserv ? strlen(dports) : 0), dports,
+ dserv, "(", dport, dserv, ")");
+ s->pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
+ ssh2_pkt_addstring(s->pktout, "tcpip-forward");
+ ssh2_pkt_addbool(s->pktout, 1);/* want reply */
+ if (*saddr) {
+ ssh2_pkt_addstring(s->pktout, saddr);
+ } else if (ssh->cfg.rport_acceptall) {
+ ssh2_pkt_addstring(s->pktout, "0.0.0.0");
+ } else {
+ ssh2_pkt_addstring(s->pktout, "127.0.0.1");
+ }
+ ssh2_pkt_adduint32(s->pktout, sport);
+ ssh2_pkt_send(ssh, s->pktout);
+
+ crWaitUntilV(pktin);
+
+ if (pktin->type != SSH2_MSG_REQUEST_SUCCESS) {
+ if (pktin->type != SSH2_MSG_REQUEST_FAILURE) {
+ bombout(("Unexpected response to port "
+ "forwarding request: packet type %d",
+ pktin->type));
+ crStopV;
+ }
+ logevent("Server refused this port forwarding");
+ } else {
+ logevent("Remote port forwarding enabled");
+ }
+ }
+ }
+ sfree(sportdesc);
+ }
+ }