X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/a209e95780b2fbece7fe2eb4d6a84597fb95ce50..824e9f94230b6979e64a4e4fb8e4f535e641a844:/ssh.c diff --git a/ssh.c b/ssh.c index f5683a32..8d310e1b 100644 --- a/ssh.c +++ b/ssh.c @@ -68,6 +68,10 @@ #define SSH1_AUTH_TIS 5 /* 0x5 */ #define SSH1_AUTH_CCARD 16 /* 0x10 */ +#define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */ +/* Mask for protoflags we will echo back to server if seen */ +#define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */ + #define SSH2_MSG_DISCONNECT 1 /* 0x1 */ #define SSH2_MSG_IGNORE 2 /* 0x2 */ #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */ @@ -256,6 +260,8 @@ static Socket s = NULL; static unsigned char session_key[32]; static int ssh1_compressing; +static int ssh1_remote_protoflags; +static int ssh1_local_protoflags; static int ssh_agentfwd_enabled; static int ssh_X11_fwd_enabled; static int ssh_remote_bugs; @@ -442,11 +448,13 @@ next_packet: unsigned char *decompblk; int decomplen; #if 0 - int i; - debug(("Packet payload pre-decompression:\n")); - for (i = -1; i < pktin.length; i++) - debug((" %02x", (unsigned char)pktin.body[i])); - debug(("\r\n")); + { + int i; + debug(("Packet payload pre-decompression:\n")); + for (i = -1; i < pktin.length; i++) + debug((" %02x", (unsigned char)pktin.body[i])); + debug(("\r\n")); + } #endif zlib_decompress_block(pktin.body-1, pktin.length+1, &decompblk, &decomplen); @@ -463,10 +471,13 @@ next_packet: sfree(decompblk); pktin.length = decomplen-1; #if 0 - debug(("Packet payload post-decompression:\n")); - for (i = -1; i < pktin.length; i++) - debug((" %02x", (unsigned char)pktin.body[i])); - debug(("\r\n")); + { + int i; + debug(("Packet payload post-decompression:\n")); + for (i = -1; i < pktin.length; i++) + debug((" %02x", (unsigned char)pktin.body[i])); + debug(("\r\n")); + } #endif } @@ -1117,7 +1128,9 @@ static void ssh_detect_bugs(char *vstring) { char *imp; /* pointer to implementation part */ imp = vstring; imp += strcspn(imp, "-"); + if (*imp) imp++; imp += strcspn(imp, "-"); + if (*imp) imp++; ssh_remote_bugs = 0; @@ -1145,10 +1158,11 @@ static void ssh_detect_bugs(char *vstring) { } static int do_ssh_init(unsigned char c) { - static char *vsp; + static char vslen; static char version[10]; - static char vstring[80]; - static char vlog[sizeof(vstring)+20]; + static char *vstring; + static int vstrsize; + static char *vlog; static int i; crBegin; @@ -1168,13 +1182,18 @@ static int do_ssh_init(unsigned char c) { crReturn(1); /* get another character */ } + vstring = smalloc(16); + vstrsize = 16; strcpy(vstring, "SSH-"); - vsp = vstring+4; + vslen = 4; i = 0; while (1) { crReturn(1); /* get another char */ - if (vsp < vstring+sizeof(vstring)-1) - *vsp++ = c; + if (vslen >= vstrsize-1) { + vstrsize += 16; + vstring = srealloc(vstring, vstrsize); + } + vstring[vslen++] = c; if (i >= 0) { if (c == '-') { version[i] = '\0'; @@ -1189,11 +1208,13 @@ static int do_ssh_init(unsigned char c) { ssh_agentfwd_enabled = FALSE; rdpkt2_state.incoming_sequence = 0; - *vsp = 0; + vstring[vslen] = 0; + vlog = smalloc(20 + vslen); sprintf(vlog, "Server version: %s", vstring); ssh_detect_bugs(vstring); vlog[strcspn(vlog, "\r\n")] = '\0'; logevent(vlog); + sfree(vlog); /* * Server version "1.99" means we can choose whether we use v1 @@ -1203,7 +1224,7 @@ static int do_ssh_init(unsigned char c) { /* * This is a v2 server. Begin v2 protocol. */ - char verstring[80]; + char verstring[80], vlog[100]; sprintf(verstring, "SSH-2.0-%s", sshver); SHA_Init(&exhashbase); /* @@ -1211,11 +1232,11 @@ static int do_ssh_init(unsigned char c) { */ sha_string(&exhashbase, verstring, strlen(verstring)); sha_string(&exhashbase, vstring, strcspn(vstring, "\r\n")); - sprintf(vstring, "%s\n", verstring); sprintf(vlog, "We claim version: %s", verstring); logevent(vlog); + strcat(verstring, "\n"); logevent("Using SSH protocol version 2"); - sk_write(s, vstring, strlen(vstring)); + sk_write(s, verstring, strlen(verstring)); ssh_protocol = ssh2_protocol; ssh_version = 2; s_rdpkt = ssh2_rdpkt; @@ -1223,20 +1244,23 @@ static int do_ssh_init(unsigned char c) { /* * This is a v1 server. Begin v1 protocol. */ - sprintf(vstring, "SSH-%s-%s\n", + char verstring[80], vlog[100]; + sprintf(verstring, "SSH-%s-%s", (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"), sshver); - sprintf(vlog, "We claim version: %s", vstring); - vlog[strcspn(vlog, "\r\n")] = '\0'; + sprintf(vlog, "We claim version: %s", verstring); logevent(vlog); + strcat(verstring, "\n"); logevent("Using SSH protocol version 1"); - sk_write(s, vstring, strlen(vstring)); + sk_write(s, verstring, strlen(verstring)); ssh_protocol = ssh1_protocol; ssh_version = 1; s_rdpkt = ssh1_rdpkt; } ssh_state = SSH_STATE_BEFORE_SIZE; + sfree(vstring); + crFinish(0); } @@ -1418,9 +1442,13 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) logevent(logmsg); } + ssh1_remote_protoflags = GET_32BIT(pktin.body+8+i+j); supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j); supported_auths_mask = GET_32BIT(pktin.body+16+i+j); + ssh1_local_protoflags = ssh1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED; + ssh1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER; + MD5Init(&md5c); MD5Update(&md5c, keystr2, hostkey.bytes); MD5Update(&md5c, keystr1, servkey.bytes); @@ -1494,7 +1522,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) PKT_DATA, cookie, 8, PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF, PKT_DATA, rsabuf, len, - PKT_INT, 0, + PKT_INT, ssh1_local_protoflags, PKT_END); logevent("Trying to enable encryption..."); @@ -2054,10 +2082,16 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { char proto[20], data[64]; logevent("Requesting X11 forwarding"); x11_invent_auth(proto, sizeof(proto), data, sizeof(data)); - send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING, - PKT_STR, proto, PKT_STR, data, - PKT_INT, 0, - PKT_END); + if (ssh1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) { + send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING, + PKT_STR, proto, PKT_STR, data, + PKT_INT, 0, + PKT_END); + } else { + send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING, + PKT_STR, proto, PKT_STR, data, + PKT_END); + } do { crReturnV; } while (!ispkt); if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) { bombout(("Protocol confusion")); @@ -2106,8 +2140,8 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { zlib_decompress_init(); } - if (*cfg.remote_cmd) - send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END); + if (*cfg.remote_cmd_ptr) + send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd_ptr, PKT_END); else send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END); logevent("Started session"); @@ -2213,7 +2247,8 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { if (c) { int closetype; closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2); - send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END); + if (!(c->closes & closetype)) + send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END); if ((c->closes == 0) && (c->type == CHAN_X11)) { logevent("X11 connection closed"); assert(c->u.x11.s != NULL); @@ -2958,9 +2993,19 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) while (pktin.type == SSH2_MSG_USERAUTH_BANNER) { char *banner; int size; - ssh2_pkt_getstring(&banner, &size); - if (banner) - c_write_untrusted(banner, 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)) { + ssh2_pkt_getstring(&banner, &size); + if (banner) + c_write_untrusted(banner, size); + } crWaitUntilV(ispkt); } if (pktin.type == SSH2_MSG_USERAUTH_SUCCESS) { @@ -3089,9 +3134,11 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) continue; } - c_write_str("Authenticating with public key \""); - c_write(commentp, commentlen); - c_write_str("\" from agent\r\n"); + if (flags & FLAG_VERBOSE) { + c_write_str("Authenticating with public key \""); + c_write(commentp, commentlen); + c_write_str("\" from agent\r\n"); + } /* * Server is willing to accept the key. @@ -3557,11 +3604,11 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) if (cfg.ssh_subsys) { ssh2_pkt_addstring("subsystem"); ssh2_pkt_addbool(1); /* want reply */ - ssh2_pkt_addstring(cfg.remote_cmd); - } else if (*cfg.remote_cmd) { + ssh2_pkt_addstring(cfg.remote_cmd_ptr); + } else if (*cfg.remote_cmd_ptr) { ssh2_pkt_addstring("exec"); ssh2_pkt_addbool(1); /* want reply */ - ssh2_pkt_addstring(cfg.remote_cmd); + ssh2_pkt_addstring(cfg.remote_cmd_ptr); } else { ssh2_pkt_addstring("shell"); ssh2_pkt_addbool(1); /* want reply */ @@ -3748,7 +3795,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) c = find234(ssh_channels, &i, ssh_channelfind); if (!c) continue; /* nonexistent channel */ - mainchan->v2.remwindow += ssh2_pkt_getuint32(); + c->v2.remwindow += ssh2_pkt_getuint32(); try_send = TRUE; } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN) { char *type;