X-Git-Url: https://git.distorted.org.uk/~mdw/sgt/putty/blobdiff_plain/697d4856818a042f5adf2711a10e9cc255317892..36cac739a5586b2c6cefe40fadc06ce93eae656d:/ssh.c diff --git a/ssh.c b/ssh.c index 22b8f5e7..2410d145 100644 --- a/ssh.c +++ b/ssh.c @@ -19,9 +19,21 @@ if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \ { fprintf(stderr, "%s\n", s); fflush(stderr); } } +/* logevent, only printf-formatted. */ +void logeventf(char *fmt, ...) +{ + va_list ap; + char stuff[200]; + + va_start(ap, fmt); + vsprintf(stuff, fmt, ap); + va_end(ap); + logevent(stuff); +} + #define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, \ (s ? sk_close(s), s = NULL : 0), \ - connection_fatal msg ) + logeventf msg, connection_fatal msg ) #define SSH1_MSG_DISCONNECT 1 /* 0x1 */ #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */ @@ -168,6 +180,7 @@ static const char *const ssh2_disconnect_reasons[] = { #define BUG_CHOKES_ON_SSH1_IGNORE 1 #define BUG_SSH2_HMAC 2 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4 +#define BUG_CHOKES_ON_RSA 8 static int ssh_pkt_ctx = 0; @@ -309,6 +322,18 @@ extern void pfd_confirm(Socket s); extern void pfd_unthrottle(Socket s); extern void pfd_override_throttle(Socket s, int enable); +static void ssh2_pkt_init(int pkt_type); +static void ssh2_pkt_addbool(unsigned char value); +static void ssh2_pkt_adduint32(unsigned long value); +static void ssh2_pkt_addstring_start(void); +static void ssh2_pkt_addstring_str(char *data); +static void ssh2_pkt_addstring_data(char *data, int len); +static void ssh2_pkt_addstring(char *data); +static char *ssh2_mpint_fmt(Bignum b, int *len); +static void ssh2_pkt_addmp(Bignum b); +static int ssh2_pkt_construct(void); +static void ssh2_pkt_send(void); + /* * Buffer management constants. There are several of these for * various different purposes: @@ -770,8 +795,8 @@ static int ssh1_rdpkt(unsigned char **data, int *datalen) pktin.type == SSH1_MSG_DEBUG || pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE || pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) { - long strlen = GET_32BIT(pktin.body); - if (strlen + 4 != pktin.length) { + long stringlen = GET_32BIT(pktin.body); + if (stringlen + 4 != pktin.length) { bombout(("Received data packet with bogus string length")); crReturn(0); } @@ -780,12 +805,12 @@ static int ssh1_rdpkt(unsigned char **data, int *datalen) if (pktin.type == SSH1_MSG_DEBUG) { /* log debug message */ char buf[80]; - int strlen = GET_32BIT(pktin.body); + int stringlen = GET_32BIT(pktin.body); strcpy(buf, "Remote: "); - if (strlen > 70) - strlen = 70; - memcpy(buf + 8, pktin.body + 4, strlen); - buf[8 + strlen] = '\0'; + if (stringlen > 70) + stringlen = 70; + memcpy(buf + 8, pktin.body + 4, stringlen); + buf[8 + stringlen] = '\0'; logevent(buf); goto next_packet; } else if (pktin.type == SSH1_MSG_IGNORE) { @@ -804,7 +829,7 @@ static int ssh1_rdpkt(unsigned char **data, int *datalen) msglen = sizeof(buf) - nowlen - 1; memcpy(buf + nowlen, pktin.body + 4, msglen); buf[nowlen + msglen] = '\0'; - logevent(buf); + /* logevent(buf); (this is now done within the bombout macro) */ bombout(("Server sent disconnect message:\n\"%s\"", buf+nowlen)); crReturn(0); } @@ -945,36 +970,105 @@ static int ssh2_rdpkt(unsigned char **data, int *datalen) log_packet(PKT_INCOMING, pktin.type, ssh2_pkt_type(pktin.type), pktin.data+6, pktin.length-6); - if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG) - goto next_packet; /* FIXME: print DEBUG message */ - - if (pktin.type == SSH2_MSG_DISCONNECT) { - /* log reason code in disconnect message */ - char buf[256]; - int reason = GET_32BIT(pktin.data + 6); - unsigned msglen = GET_32BIT(pktin.data + 10); - unsigned nowlen; - if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) { - sprintf(buf, "Received disconnect message (%s)", - ssh2_disconnect_reasons[reason]); - } else { - sprintf(buf, "Received disconnect message (unknown type %d)", - reason); + switch (pktin.type) { + /* + * These packets we must handle instantly. + */ + case SSH2_MSG_DISCONNECT: + { + /* log reason code in disconnect message */ + char buf[256]; + int reason = GET_32BIT(pktin.data + 6); + unsigned msglen = GET_32BIT(pktin.data + 10); + unsigned nowlen; + if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) { + sprintf(buf, "Received disconnect message (%s)", + ssh2_disconnect_reasons[reason]); + } else { + sprintf(buf, "Received disconnect message (unknown type %d)", + reason); + } + logevent(buf); + strcpy(buf, "Disconnection message text: "); + nowlen = strlen(buf); + if (msglen > sizeof(buf) - nowlen - 1) + msglen = sizeof(buf) - nowlen - 1; + memcpy(buf + nowlen, pktin.data + 14, msglen); + buf[nowlen + msglen] = '\0'; + logevent(buf); + bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"", + reason, + (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ? + ssh2_disconnect_reasons[reason] : "unknown", + buf+nowlen)); + crReturn(0); + } + break; + case SSH2_MSG_IGNORE: + goto next_packet; + case SSH2_MSG_DEBUG: + { + /* log the debug message */ + char buf[512]; + /* int display = pktin.body[6]; */ + int stringlen = GET_32BIT(pktin.data+7); + int prefix; + strcpy(buf, "Remote debug message: "); + prefix = strlen(buf); + if (stringlen > sizeof(buf)-prefix-1) + stringlen = sizeof(buf)-prefix-1; + memcpy(buf + prefix, pktin.data + 11, stringlen); + buf[prefix + stringlen] = '\0'; + logevent(buf); } - logevent(buf); - strcpy(buf, "Disconnection message text: "); - nowlen = strlen(buf); - if (msglen > sizeof(buf) - nowlen - 1) - msglen = sizeof(buf) - nowlen - 1; - memcpy(buf + nowlen, pktin.data + 14, msglen); - buf[nowlen + msglen] = '\0'; - logevent(buf); - bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"", - reason, - (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ? - ssh2_disconnect_reasons[reason] : "unknown", - buf+nowlen)); - crReturn(0); + goto next_packet; /* FIXME: print the debug message */ + + /* + * These packets we need do nothing about here. + */ + case SSH2_MSG_UNIMPLEMENTED: + case SSH2_MSG_SERVICE_REQUEST: + case SSH2_MSG_SERVICE_ACCEPT: + case SSH2_MSG_KEXINIT: + case SSH2_MSG_NEWKEYS: + case SSH2_MSG_KEXDH_INIT: + case SSH2_MSG_KEXDH_REPLY: + /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */ + /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */ + case SSH2_MSG_KEX_DH_GEX_INIT: + case SSH2_MSG_KEX_DH_GEX_REPLY: + case SSH2_MSG_USERAUTH_REQUEST: + case SSH2_MSG_USERAUTH_FAILURE: + case SSH2_MSG_USERAUTH_SUCCESS: + case SSH2_MSG_USERAUTH_BANNER: + case SSH2_MSG_USERAUTH_PK_OK: + /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */ + /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */ + case SSH2_MSG_USERAUTH_INFO_RESPONSE: + case SSH2_MSG_GLOBAL_REQUEST: + case SSH2_MSG_REQUEST_SUCCESS: + case SSH2_MSG_REQUEST_FAILURE: + case SSH2_MSG_CHANNEL_OPEN: + case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION: + case SSH2_MSG_CHANNEL_OPEN_FAILURE: + case SSH2_MSG_CHANNEL_WINDOW_ADJUST: + case SSH2_MSG_CHANNEL_DATA: + case SSH2_MSG_CHANNEL_EXTENDED_DATA: + case SSH2_MSG_CHANNEL_EOF: + case SSH2_MSG_CHANNEL_CLOSE: + case SSH2_MSG_CHANNEL_REQUEST: + case SSH2_MSG_CHANNEL_SUCCESS: + case SSH2_MSG_CHANNEL_FAILURE: + break; + + /* + * For anything else we send SSH2_MSG_UNIMPLEMENTED. + */ + default: + ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED); + ssh2_pkt_adduint32(st->incoming_sequence - 1); + ssh2_pkt_send(); + break; } crFinish(0); @@ -1509,6 +1603,16 @@ static void ssh_detect_bugs(char *vstring) logevent("We believe remote version needs a plain SSH1 password"); } + if (!strcmp(imp, "Cisco-1.25")) { + /* + * These versions apparently have no clue whatever about + * RSA authentication and will panic and die if they see + * an AUTH_RSA message. + */ + ssh_remote_bugs |= BUG_CHOKES_ON_RSA; + logevent("We believe remote version can't handle RSA authentication"); + } + if (!strncmp(imp, "2.1.0", 5) || !strncmp(imp, "2.0.", 4) || !strncmp(imp, "2.2.0", 5) || !strncmp(imp, "2.3.0", 5) || !strncmp(imp, "2.1 ", 4)) { @@ -1618,6 +1722,12 @@ static int do_ssh_init(unsigned char c) sprintf(vlog, "We claim version: %s", verstring); logevent(vlog); strcat(verstring, "\n"); + + if (cfg.sshprot == 3) { + bombout(("SSH protocol version 2 required by user but not provided by server")); + crReturn(0); + } + logevent("Using SSH protocol version 1"); sk_write(s, verstring, strlen(verstring)); ssh_protocol = ssh1_protocol; @@ -1687,6 +1797,7 @@ static int ssh_closing(Plug plug, char *error_msg, int error_code, } if (error_msg) { /* A socket error has occurred. */ + logevent(error_msg); connection_fatal(error_msg); } else { /* Otherwise, the remote side closed the connection normally. */ @@ -1780,9 +1891,11 @@ static char *connect_to_host(char *host, int port, char **realhost, int nodelay) sprintf(buf, "Connecting to %.100s port %d", addrbuf, port); logevent(buf); } - s = sk_new(addr, port, 0, 1, nodelay, &fn_table_ptr); - if ((err = sk_socket_error(s))) + s = new_connection(addr, *realhost, port, 0, 1, nodelay, &fn_table_ptr); + if ((err = sk_socket_error(s))) { + s = NULL; return err; + } #ifdef FWHACK sk_write(s, "connect ", 8); @@ -2074,8 +2187,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) break; case 3: case 4: - random_save_seed(); - exit(0); + cleanup_exit(0); break; default: if (((c >= ' ' && c <= '~') || @@ -2110,7 +2222,12 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) crWaitUntil(ispkt); - tried_publickey = tried_agent = 0; + if ((ssh_remote_bugs & BUG_CHOKES_ON_RSA)) { + /* We must not attempt PK auth. Pretend we've already tried it. */ + tried_publickey = tried_agent = 1; + } else { + tried_publickey = tried_agent = 0; + } tis_auth_refused = ccard_auth_refused = 0; /* Load the public half of cfg.keyfile so we notice if it's in Pageant */ if (*cfg.keyfile) { @@ -2319,8 +2436,22 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) } if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { char *comment = NULL; + int type; + char msgbuf[256]; if (flags & FLAG_VERBOSE) c_write_str("Trying public key authentication.\r\n"); + sprintf(msgbuf, "Trying public key \"%.200s\"", cfg.keyfile); + logevent(msgbuf); + type = key_type(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(msgbuf); + c_write_str("\r\n"); + tried_publickey = 1; + continue; + } if (!rsakey_encrypted(cfg.keyfile, &comment)) { if (flags & FLAG_VERBOSE) c_write_str("No passphrase required.\r\n"); @@ -2345,6 +2476,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) send_packet(SSH1_MSG_DISCONNECT, PKT_STR, "No more passwords available to try", PKT_END); + logevent("Unable to authenticate"); connection_fatal("Unable to authenticate"); ssh_state = SSH_STATE_CLOSED; crReturn(1); @@ -2375,8 +2507,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) break; case 3: case 4: - random_save_seed(); - exit(0); + cleanup_exit(0); break; default: if (pos < sizeof(password)-1) @@ -2608,7 +2739,7 @@ void sshfwd_close(struct ssh_channel *c) * on it now, and then when the server acks the channel * open, we can close it then. */ - if (c->remoteid != -1) { + if (((int)c->remoteid) != -1) { if (ssh_version == 1) { send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid, PKT_END); @@ -2720,11 +2851,13 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) } { - char type, *e; + char type; + static char *e; int n; - int sport,dport; + int sport,dport,sserv,dserv; char sports[256], dports[256], host[256]; char buf[1024]; + struct servent *se; ssh_rportfwds = newtree234(ssh_rportcmp_ssh1); /* Add port forwardings. */ @@ -2749,12 +2882,43 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) dports[n] = 0; e++; dport = atoi(dports); + dserv = 0; + if (dport == 0) { + dserv = 1; + se = getservbyname(dports, NULL); + if (se != NULL) { + dport = ntohs(se->s_port); + } else { + sprintf(buf, + "Service lookup failed for destination port \"%s\"", + dports); + logevent(buf); + } + } sport = atoi(sports); + sserv = 0; + if (sport == 0) { + sserv = 1; + se = getservbyname(sports, NULL); + if (se != NULL) { + sport = ntohs(se->s_port); + } else { + sprintf(buf, + "Service lookup failed for source port \"%s\"", + sports); + logevent(buf); + } + } if (sport && dport) { if (type == 'L') { pfd_addforward(host, dport, sport); - sprintf(buf, "Local port %d forwarding to %s:%d", - sport, host, dport); + sprintf(buf, "Local port %.*s%.*s%d%.*s forwarding to" + " %s:%.*s%.*s%d%.*s", + sserv ? strlen(sports) : 0, sports, + sserv, "(", sport, sserv, ")", + host, + dserv ? strlen(dports) : 0, dports, + dserv, "(", dport, dserv, ")"); logevent(buf); } else { struct ssh_rportfwd *pf; @@ -2768,14 +2932,31 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) logevent(buf); sfree(pf); } else { - sprintf(buf, "Requesting remote port %d forward to %s:%d", - sport, host, dport); + sprintf(buf, "Requesting remote port %.*s%.*s%d%.*s" + " forward to %s:%.*s%.*s%d%.*s", + sserv ? strlen(sports) : 0, sports, + sserv, "(", sport, sserv, ")", + host, + dserv ? strlen(dports) : 0, dports, + dserv, "(", dport, dserv, ")"); logevent(buf); send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST, PKT_INT, sport, PKT_STR, host, PKT_INT, dport, PKT_END); + do { + crReturnV; + } while (!ispkt); + if (pktin.type != SSH1_SMSG_SUCCESS + && pktin.type != SSH1_SMSG_FAILURE) { + bombout(("Protocol confusion")); + crReturnV; + } else if (pktin.type == SSH1_SMSG_FAILURE) { + c_write_str("Server refused port forwarding\r\n"); + ssh_editing = ssh_echoing = 1; + } + logevent("Remote port forwarding enabled"); } } } @@ -3776,6 +3957,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) static int we_are_in; static int num_prompts, echo; static char username[100]; + static int got_username; static char pwprompt[200]; static char password[100]; static void *publickey_blob; @@ -3820,6 +4002,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) * retype it! */ username[0] = '\0'; + got_username = FALSE; do { static int pos; static char c; @@ -3828,7 +4011,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) * Get a username. */ pos = 0; - if (*username && !cfg.change_username) { + if (got_username && !cfg.change_username) { /* * We got a username last time round this loop, and * with change_username turned off we don't try to get @@ -3874,8 +4057,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) break; case 3: case 4: - random_save_seed(); - exit(0); + cleanup_exit(0); break; default: if (((c >= ' ' && c <= '~') || @@ -3899,6 +4081,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) c_write_str(stuff); } } + got_username = TRUE; /* * Send an authentication request using method "none": (a) @@ -3922,8 +4105,21 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) kbd_inter_running = FALSE; /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */ if (*cfg.keyfile) { - publickey_blob = ssh2_userkey_loadpub(cfg.keyfile, NULL, - &publickey_bloblen); + int keytype; + logeventf("Reading private key file \"%.150s\"", cfg.keyfile); + keytype = key_type(cfg.keyfile); + if (keytype == SSH_KEYTYPE_SSH2) + publickey_blob = ssh2_userkey_loadpub(cfg.keyfile, NULL, + &publickey_bloblen); + else { + char msgbuf[256]; + logeventf("Unable to use this key file (%s)", + key_type_to_str(keytype)); + sprintf(msgbuf, "Unable to use key file \"%.150s\" (%s)\r\n", + cfg.keyfile, key_type_to_str(keytype)); + c_write_str(msgbuf); + publickey_blob = NULL; + } } else publickey_blob = NULL; @@ -4182,7 +4378,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) } } - if (!method && can_pubkey && *cfg.keyfile + if (!method && can_pubkey && publickey_blob && !tried_pubkey_config) { unsigned char *pub_blob; char *algorithm, *comment; @@ -4321,6 +4517,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) ("No more passwords available to try"); ssh2_pkt_addstring("en"); /* language tag */ ssh2_pkt_send(); + logevent("Unable to authenticate"); connection_fatal("Unable to authenticate"); ssh_state = SSH_STATE_CLOSED; crReturnV; @@ -4353,8 +4550,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) break; case 3: case 4: - random_save_seed(); - exit(0); + cleanup_exit(0); break; default: if (pos < sizeof(password)-1) @@ -4601,9 +4797,10 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) static char *e; /* preserve across crReturn */ char type; int n; - int sport,dport; + int sport,dport,sserv,dserv; char sports[256], dports[256], host[256]; char buf[1024]; + struct servent *se; ssh_rportfwds = newtree234(ssh_rportcmp_ssh2); /* Add port forwardings. */ @@ -4628,12 +4825,43 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) dports[n] = 0; e++; dport = atoi(dports); + dserv = 0; + if (dport == 0) { + dserv = 1; + se = getservbyname(dports, NULL); + if (se != NULL) { + dport = ntohs(se->s_port); + } else { + sprintf(buf, + "Service lookup failed for destination port \"%s\"", + dports); + logevent(buf); + } + } sport = atoi(sports); + sserv = 0; + if (sport == 0) { + sserv = 1; + se = getservbyname(sports, NULL); + if (se != NULL) { + sport = ntohs(se->s_port); + } else { + sprintf(buf, + "Service lookup failed for source port \"%s\"", + sports); + logevent(buf); + } + } if (sport && dport) { if (type == 'L') { pfd_addforward(host, dport, sport); - sprintf(buf, "Local port %d forwarding to %s:%d", - sport, host, dport); + sprintf(buf, "Local port %.*s%.*s%d%.*s forwarding to" + " %s:%.*s%.*s%d%.*s", + sserv ? strlen(sports) : 0, sports, + sserv, "(", sport, sserv, ")", + host, + dserv ? strlen(dports) : 0, dports, + dserv, "(", dport, dserv, ")"); logevent(buf); } else { struct ssh_rportfwd *pf; @@ -4648,8 +4876,13 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) logevent(buf); sfree(pf); } else { - sprintf(buf, "Requesting remote port %d (forwarded to %s:%d)", - sport, host, dport); + sprintf(buf, "Requesting remote port %.*s%.*s%d%.*s" + " forward to %s:%.*s%.*s%d%.*s", + sserv ? strlen(sports) : 0, sports, + sserv, "(", sport, sserv, ")", + host, + dserv ? strlen(dports) : 0, dports, + dserv, "(", dport, dserv, ")"); logevent(buf); ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST); ssh2_pkt_addstring("tcpip-forward"); @@ -5102,7 +5335,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) ssh2_pkt_addstring(buf); ssh2_pkt_addstring("en"); /* language tag */ ssh2_pkt_send(); - connection_fatal(buf); + connection_fatal("%s", buf); ssh_state = SSH_STATE_CLOSED; crReturnV; }