X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/d5859615f641e5bbd853cd42aafd4fa577da17eb..fe50e8140a2dbb3ba357a0ab777f34e07d568c23:/ssh.c diff --git a/ssh.c b/ssh.c index 9fbcf463..c065f2f8 100644 --- a/ssh.c +++ b/ssh.c @@ -25,7 +25,7 @@ if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \ fprintf(stderr, "%s\n", s); } -#define bombout(msg) ( ssh_state == SSH_STATE_CLOSED, closesocket(s), \ +#define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, closesocket(s), \ s = INVALID_SOCKET, connection_fatal msg ) #define SSH1_MSG_DISCONNECT 1 /* 0x1 */ @@ -147,63 +147,43 @@ enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM }; #define crWaitUntil(c) do { crReturn(0); } while (!(c)) #define crWaitUntilV(c) do { crReturnV; } while (!(c)) -extern struct ssh_cipher ssh_3des; -extern struct ssh_cipher ssh_3des_ssh2; -extern struct ssh_cipher ssh_des; -extern struct ssh_cipher ssh_blowfish_ssh1; -extern struct ssh_cipher ssh_blowfish_ssh2; +extern const struct ssh_cipher ssh_3des; +extern const struct ssh_cipher ssh_3des_ssh2; +extern const struct ssh_cipher ssh_des; +extern const struct ssh_cipher ssh_blowfish_ssh1; +extern const struct ssh_cipher ssh_blowfish_ssh2; /* * Ciphers for SSH2. We miss out single-DES because it isn't * supported; also 3DES and Blowfish are both done differently from * SSH1. (3DES uses outer chaining; Blowfish has the opposite * endianness and different-sized keys.) - * - * The first entry in this array is set up to be whatever the user - * asks for as a cipher. Thereafter there is a fixed preference - * order of fallback ciphers. */ -struct ssh_cipher *ciphers[] = { NULL, &ssh_blowfish_ssh2, &ssh_3des_ssh2 }; - -extern struct ssh_kex ssh_diffiehellman; -struct ssh_kex *kex_algs[] = { &ssh_diffiehellman }; +const static struct ssh_cipher *ciphers[] = { &ssh_blowfish_ssh2, &ssh_3des_ssh2 }; -extern struct ssh_hostkey ssh_dss; -struct ssh_hostkey *hostkey_algs[] = { &ssh_dss }; +extern const struct ssh_kex ssh_diffiehellman; +const static struct ssh_kex *kex_algs[] = { &ssh_diffiehellman }; -extern struct ssh_mac ssh_sha1; +extern const struct ssh_hostkey ssh_dss; +const static struct ssh_hostkey *hostkey_algs[] = { &ssh_dss }; -static SHA_State exhash; +extern const struct ssh_mac ssh_md5, ssh_sha1, ssh_sha1_buggy; static void nullmac_key(unsigned char *key) { } static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { } static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; } -struct ssh_mac ssh_mac_none = { +const static struct ssh_mac ssh_mac_none = { nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0 }; -struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none }; +const static struct ssh_mac *macs[] = { + &ssh_sha1, &ssh_md5, &ssh_mac_none }; +const static struct ssh_mac *buggymacs[] = { + &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none }; -struct ssh_compress ssh_comp_none = { +const static struct ssh_compress ssh_comp_none = { "none" }; -struct ssh_compress *compressions[] = { &ssh_comp_none }; - -static SOCKET s = INVALID_SOCKET; - -static unsigned char session_key[32]; -static struct ssh_cipher *cipher = NULL; -static struct ssh_cipher *cscipher = NULL; -static struct ssh_cipher *sccipher = NULL; -static struct ssh_mac *csmac = NULL; -static struct ssh_mac *scmac = NULL; -static struct ssh_compress *cscomp = NULL; -static struct ssh_compress *sccomp = NULL; -static struct ssh_kex *kex = NULL; -static struct ssh_hostkey *hostkey = NULL; -int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL; - -static char *savedhost; -static int ssh_send_ok; +const static struct ssh_compress *compressions[] = { &ssh_comp_none }; /* * 2-3-4 tree storing channels. @@ -225,7 +205,74 @@ struct ssh_channel { } v2; } u; }; + +struct Packet { + long length; + int type; + unsigned char *data; + unsigned char *body; + long savedpos; + long maxlen; +}; + +static SHA_State exhash; + +static SOCKET s = INVALID_SOCKET; + +static unsigned char session_key[32]; +static const struct ssh_cipher *cipher = NULL; +static const struct ssh_cipher *cscipher = NULL; +static const struct ssh_cipher *sccipher = NULL; +static const struct ssh_mac *csmac = NULL; +static const struct ssh_mac *scmac = NULL; +static const struct ssh_compress *cscomp = NULL; +static const struct ssh_compress *sccomp = NULL; +static const struct ssh_kex *kex = NULL; +static const struct ssh_hostkey *hostkey = NULL; +int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL; + +static char *savedhost; +static int savedport; +static int ssh_send_ok; + static tree234 *ssh_channels; /* indexed by local id */ +static struct ssh_channel *mainchan; /* primary session channel */ + +static enum { + SSH_STATE_BEFORE_SIZE, + SSH_STATE_INTERMED, + SSH_STATE_SESSION, + SSH_STATE_CLOSED +} ssh_state = SSH_STATE_BEFORE_SIZE; + +static int size_needed = FALSE; + +static struct Packet pktin = { 0, 0, NULL, NULL, 0 }; +static struct Packet pktout = { 0, 0, NULL, NULL, 0 }; + +static int ssh_version; +static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt); +static void ssh1_protocol(unsigned char *in, int inlen, int ispkt); +static void ssh2_protocol(unsigned char *in, int inlen, int ispkt); +static void ssh_size(void); + +static int (*s_rdpkt)(unsigned char **data, int *datalen); + +static struct rdpkt1_state_tag { + long len, pad, biglen, to_read; + unsigned long realcrc, gotcrc; + unsigned char *p; + int i; + int chunk; +} rdpkt1_state; + +static struct rdpkt2_state_tag { + long len, pad, payload, packetlen, maclen; + int i; + int cipherblk; + unsigned long incoming_sequence; +} rdpkt2_state; + static int ssh_channelcmp(void *av, void *bv) { struct ssh_channel *a = (struct ssh_channel *)av; struct ssh_channel *b = (struct ssh_channel *)bv; @@ -241,17 +288,6 @@ static int ssh_channelfind(void *av, void *bv) { return 0; } -static struct ssh_channel *mainchan; /* primary session channel */ - -static enum { - SSH_STATE_BEFORE_SIZE, - SSH_STATE_INTERMED, - SSH_STATE_SESSION, - SSH_STATE_CLOSED -} ssh_state = SSH_STATE_BEFORE_SIZE; - -static int size_needed = FALSE; - static void s_write (char *buf, int len) { while (len > 0) { int i = send (s, buf, len, 0); @@ -286,35 +322,9 @@ static void c_write (char *buf, int len) { fputc(buf[i], stderr); return; } - while (len--) - c_write1(*buf++); -} - -static void c_writedata (char *buf, int len) { - while (len--) - c_write1(*buf++); + from_backend(1, buf, len); } -struct Packet { - long length; - int type; - unsigned char *data; - unsigned char *body; - long savedpos; - long maxlen; -}; - -static struct Packet pktin = { 0, 0, NULL, NULL, 0 }; -static struct Packet pktout = { 0, 0, NULL, NULL, 0 }; - -static int ssh_version; -static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt); -static void ssh1_protocol(unsigned char *in, int inlen, int ispkt); -static void ssh2_protocol(unsigned char *in, int inlen, int ispkt); -static void ssh_size(void); - -static int (*s_rdpkt)(unsigned char **data, int *datalen); - /* * Collect incoming data in the incoming packet buffer. * Decipher and verify the packet when it is completely read. @@ -325,10 +335,7 @@ static int (*s_rdpkt)(unsigned char **data, int *datalen); */ static int ssh1_rdpkt(unsigned char **data, int *datalen) { - static long len, pad, biglen, to_read; - static unsigned long realcrc, gotcrc; - static unsigned char *p; - static int i; + struct rdpkt1_state_tag *st = &rdpkt1_state; crBegin; @@ -337,56 +344,61 @@ next_packet: pktin.type = 0; pktin.length = 0; - for (i = len = 0; i < 4; i++) { + for (st->i = st->len = 0; st->i < 4; st->i++) { while ((*datalen) == 0) - crReturn(4-i); - len = (len << 8) + **data; + crReturn(4-st->i); + st->len = (st->len << 8) + **data; (*data)++, (*datalen)--; } #ifdef FWHACK - if (len == 0x52656d6f) { /* "Remo"te server has closed ... */ - len = 0x300; /* big enough to carry to end */ + if (st->len == 0x52656d6f) { /* "Remo"te server has closed ... */ + st->len = 0x300; /* big enough to carry to end */ } #endif - pad = 8 - (len % 8); - biglen = len + pad; - pktin.length = len - 5; + st->pad = 8 - (st->len % 8); + st->biglen = st->len + st->pad; + pktin.length = st->len - 5; - if (pktin.maxlen < biglen) { - pktin.maxlen = biglen; - pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) : - realloc(pktin.data, biglen+APIEXTRA)); + if (pktin.maxlen < st->biglen) { + pktin.maxlen = st->biglen; + pktin.data = (pktin.data == NULL ? malloc(st->biglen+APIEXTRA) : + realloc(pktin.data, st->biglen+APIEXTRA)); if (!pktin.data) fatalbox("Out of memory"); } - to_read = biglen; - p = pktin.data; - while (to_read > 0) { - static int chunk; - chunk = to_read; + st->to_read = st->biglen; + st->p = pktin.data; + while (st->to_read > 0) { + st->chunk = st->to_read; while ((*datalen) == 0) - crReturn(to_read); - if (chunk > (*datalen)) - chunk = (*datalen); - memcpy(p, *data, chunk); - *data += chunk; - *datalen -= chunk; - p += chunk; - to_read -= chunk; + crReturn(st->to_read); + if (st->chunk > (*datalen)) + st->chunk = (*datalen); + memcpy(st->p, *data, st->chunk); + *data += st->chunk; + *datalen -= st->chunk; + st->p += st->chunk; + st->to_read -= st->chunk; } if (cipher) - cipher->decrypt(pktin.data, biglen); + cipher->decrypt(pktin.data, st->biglen); +#if 0 + debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad)); + for (st->i = 0; st->i < st->biglen; st->i++) + debug((" %02x", (unsigned char)pktin.data[st->i])); + debug(("\r\n")); +#endif - pktin.type = pktin.data[pad]; - pktin.body = pktin.data + pad + 1; + pktin.type = pktin.data[st->pad]; + pktin.body = pktin.data + st->pad + 1; - realcrc = crc32(pktin.data, biglen-4); - gotcrc = GET_32BIT(pktin.data+biglen-4); - if (gotcrc != realcrc) { + st->realcrc = crc32(pktin.data, st->biglen-4); + st->gotcrc = GET_32BIT(pktin.data+st->biglen-4); + if (st->gotcrc != st->realcrc) { bombout(("Incorrect CRC received on packet")); crReturn(0); } @@ -423,29 +435,24 @@ next_packet: static int ssh2_rdpkt(unsigned char **data, int *datalen) { - static long len, pad, payload, packetlen, maclen; - static int i; - static int cipherblk; - static unsigned long incoming_sequence = 0; + struct rdpkt2_state_tag *st = &rdpkt2_state; crBegin; next_packet: - pktin.type = 0; pktin.length = 0; - - if (cipher) - cipherblk = cipher->blksize; + if (sccipher) + st->cipherblk = sccipher->blksize; else - cipherblk = 8; - if (cipherblk < 8) - cipherblk = 8; - - if (pktin.maxlen < cipherblk) { - pktin.maxlen = cipherblk; - pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) : - realloc(pktin.data, cipherblk+APIEXTRA)); + st->cipherblk = 8; + if (st->cipherblk < 8) + st->cipherblk = 8; + + if (pktin.maxlen < st->cipherblk) { + pktin.maxlen = st->cipherblk; + pktin.data = (pktin.data == NULL ? malloc(st->cipherblk+APIEXTRA) : + realloc(pktin.data, st->cipherblk+APIEXTRA)); if (!pktin.data) fatalbox("Out of memory"); } @@ -454,10 +461,10 @@ next_packet: * Acquire and decrypt the first block of the packet. This will * contain the length and padding details. */ - for (i = len = 0; i < cipherblk; i++) { + for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) { while ((*datalen) == 0) - crReturn(cipherblk-i); - pktin.data[i] = *(*data)++; + crReturn(st->cipherblk-st->i); + pktin.data[st->i] = *(*data)++; (*datalen)--; } #ifdef FWHACK @@ -466,32 +473,32 @@ next_packet: } #endif if (sccipher) - sccipher->decrypt(pktin.data, cipherblk); + sccipher->decrypt(pktin.data, st->cipherblk); /* * Now get the length and padding figures. */ - len = GET_32BIT(pktin.data); - pad = pktin.data[4]; + st->len = GET_32BIT(pktin.data); + st->pad = pktin.data[4]; /* * This enables us to deduce the payload length. */ - payload = len - pad - 1; + st->payload = st->len - st->pad - 1; - pktin.length = payload + 5; + pktin.length = st->payload + 5; /* * So now we can work out the total packet length. */ - packetlen = len + 4; - maclen = scmac ? scmac->len : 0; + st->packetlen = st->len + 4; + st->maclen = scmac ? scmac->len : 0; /* * Adjust memory allocation if packet is too big. */ - if (pktin.maxlen < packetlen+maclen) { - pktin.maxlen = packetlen+maclen; + if (pktin.maxlen < st->packetlen+st->maclen) { + pktin.maxlen = st->packetlen+st->maclen; pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) : realloc(pktin.data, pktin.maxlen+APIEXTRA)); if (!pktin.data) @@ -501,31 +508,32 @@ next_packet: /* * Read and decrypt the remainder of the packet. */ - for (i = cipherblk; i < packetlen + maclen; i++) { + for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; st->i++) { while ((*datalen) == 0) - crReturn(packetlen + maclen - i); - pktin.data[i] = *(*data)++; + crReturn(st->packetlen + st->maclen - st->i); + pktin.data[st->i] = *(*data)++; (*datalen)--; } /* Decrypt everything _except_ the MAC. */ if (sccipher) - sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk); + sccipher->decrypt(pktin.data + st->cipherblk, + st->packetlen - st->cipherblk); #if 0 - debug(("Got packet len=%d pad=%d\r\n", len, pad)); - for (i = 0; i < packetlen; i++) - debug((" %02x", (unsigned char)pktin.data[i])); + debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad)); + for (st->i = 0; st->i < st->packetlen; st->i++) + debug((" %02x", (unsigned char)pktin.data[st->i])); debug(("\r\n")); #endif /* * Check the MAC. */ - if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) { + if (scmac && !scmac->verify(pktin.data, st->len+4, st->incoming_sequence)) { bombout(("Incorrect MAC received on packet")); crReturn(0); } - incoming_sequence++; /* whether or not we MACed */ + st->incoming_sequence++; /* whether or not we MACed */ pktin.savedpos = 6; pktin.type = pktin.data[5]; @@ -591,6 +599,12 @@ static void s_wrpkt(void) { PUT_32BIT(pktout.data+biglen, crc); PUT_32BIT(pktout.data, len); +#if 0 + debug(("Sending packet len=%d\r\n", biglen+4)); + for (i = 0; i < biglen+4; i++) + debug((" %02x", (unsigned char)pktout.data[i])); + debug(("\r\n")); +#endif if (cipher) cipher->encrypt(pktout.data+4, biglen); @@ -704,6 +718,7 @@ static char *connect_to_host(char *host, int port, char **realhost) if (port < 0) port = 22; /* default ssh port */ + savedport = port; #ifdef FWHACK FWhost = host; @@ -804,7 +819,7 @@ static int ssh_versioncmp(char *a, char *b) { * state. */ #include -void sha_string(SHA_State *s, void *str, int len) { +static void sha_string(SHA_State *s, void *str, int len) { unsigned char lenblk[4]; PUT_32BIT(lenblk, len); SHA_Bytes(s, lenblk, 4); @@ -814,7 +829,7 @@ void sha_string(SHA_State *s, void *str, int len) { /* * SSH2 packet construction functions. */ -void ssh2_pkt_adddata(void *data, int len) { +static void ssh2_pkt_adddata(void *data, int len) { pktout.length += len; if (pktout.maxlen < pktout.length) { pktout.maxlen = pktout.length + 256; @@ -825,40 +840,40 @@ void ssh2_pkt_adddata(void *data, int len) { } memcpy(pktout.data+pktout.length-len, data, len); } -void ssh2_pkt_addbyte(unsigned char byte) { +static void ssh2_pkt_addbyte(unsigned char byte) { ssh2_pkt_adddata(&byte, 1); } -void ssh2_pkt_init(int pkt_type) { +static void ssh2_pkt_init(int pkt_type) { pktout.length = 5; ssh2_pkt_addbyte((unsigned char)pkt_type); } -void ssh2_pkt_addbool(unsigned char value) { +static void ssh2_pkt_addbool(unsigned char value) { ssh2_pkt_adddata(&value, 1); } -void ssh2_pkt_adduint32(unsigned long value) { +static void ssh2_pkt_adduint32(unsigned long value) { unsigned char x[4]; PUT_32BIT(x, value); ssh2_pkt_adddata(x, 4); } -void ssh2_pkt_addstring_start(void) { +static void ssh2_pkt_addstring_start(void) { ssh2_pkt_adduint32(0); pktout.savedpos = pktout.length; } -void ssh2_pkt_addstring_str(char *data) { +static void ssh2_pkt_addstring_str(char *data) { ssh2_pkt_adddata(data, strlen(data)); PUT_32BIT(pktout.data + pktout.savedpos - 4, pktout.length - pktout.savedpos); } -void ssh2_pkt_addstring_data(char *data, int len) { +static void ssh2_pkt_addstring_data(char *data, int len) { ssh2_pkt_adddata(data, len); PUT_32BIT(pktout.data + pktout.savedpos - 4, pktout.length - pktout.savedpos); } -void ssh2_pkt_addstring(char *data) { +static void ssh2_pkt_addstring(char *data) { ssh2_pkt_addstring_start(); ssh2_pkt_addstring_str(data); } -char *ssh2_mpint_fmt(Bignum b, int *len) { +static char *ssh2_mpint_fmt(Bignum b, int *len) { unsigned char *p; int i, n = b[0]; p = malloc(n * 2 + 1); @@ -876,7 +891,7 @@ char *ssh2_mpint_fmt(Bignum b, int *len) { *len = n*2+1-i; return p; } -void ssh2_pkt_addmp(Bignum b) { +static void ssh2_pkt_addmp(Bignum b) { unsigned char *p; int len; p = ssh2_mpint_fmt(b, &len); @@ -884,7 +899,7 @@ void ssh2_pkt_addmp(Bignum b) { ssh2_pkt_addstring_data(p, len); free(p); } -void ssh2_pkt_send(void) { +static void ssh2_pkt_send(void) { int cipherblk, maclen, padding, i; static unsigned long outgoing_sequence = 0; @@ -932,7 +947,7 @@ void bndebug(char *string, Bignum b) { } #endif -void sha_mpint(SHA_State *s, Bignum b) { +static void sha_mpint(SHA_State *s, Bignum b) { unsigned char *p; int len; p = ssh2_mpint_fmt(b, &len); @@ -943,7 +958,7 @@ void sha_mpint(SHA_State *s, Bignum b) { /* * SSH2 packet decode functions. */ -unsigned long ssh2_pkt_getuint32(void) { +static unsigned long ssh2_pkt_getuint32(void) { unsigned long value; if (pktin.length - pktin.savedpos < 4) return 0; /* arrgh, no way to decline (FIXME?) */ @@ -951,7 +966,7 @@ unsigned long ssh2_pkt_getuint32(void) { pktin.savedpos += 4; return value; } -void ssh2_pkt_getstring(char **p, int *length) { +static void ssh2_pkt_getstring(char **p, int *length) { *p = NULL; if (pktin.length - pktin.savedpos < 4) return; @@ -962,7 +977,7 @@ void ssh2_pkt_getstring(char **p, int *length) { *p = pktin.data+pktin.savedpos; pktin.savedpos += *length; } -Bignum ssh2_pkt_getmp(void) { +static Bignum ssh2_pkt_getmp(void) { char *p; int i, j, length; Bignum b; @@ -1025,6 +1040,8 @@ static int do_ssh_init(void) { break; } + rdpkt2_state.incoming_sequence = 0; + *vsp = 0; sprintf(vlog, "Server version: %s", vstring); vlog[strcspn(vlog, "\r\n")] = '\0'; @@ -1086,6 +1103,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) static int tried_publickey; static unsigned char session_id[16]; int cipher_type; + static char username[100]; crBegin; @@ -1148,7 +1166,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) fatalbox("Out of memory"); rsastr_fmt(keystr, &hostkey); rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey); - verify_ssh_host_key(savedhost, "rsa", keystr, fingerprint); + verify_ssh_host_key(savedhost, savedport, "rsa", keystr, fingerprint); free(keystr); } @@ -1209,7 +1227,6 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) fflush(stdout); { - static char username[100]; static int pos = 0; static char c; if ((flags & FLAG_INTERACTIVE) && !*cfg.username) { @@ -1437,7 +1454,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) } if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) { sprintf(prompt, "%.90s@%.90s's password: ", - cfg.username, savedhost); + username, savedhost); } if (pwpkt_type == SSH1_CMSG_AUTH_RSA) { char *comment = NULL; @@ -1452,7 +1469,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) free(comment); } - if (!(flags & FLAG_INTERACTIVE)) { + if (ssh_get_password) { if (!ssh_get_password(prompt, password, sizeof(password))) { /* * get_password failed to get a password (for @@ -1508,7 +1525,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) static unsigned char buffer[32]; tried_publickey = 1; - i = loadrsakey(cfg.keyfile, &pubkey, password); + i = loadrsakey(cfg.keyfile, &pubkey, NULL, password); if (i == 0) { c_write("Couldn't load public key from ", 30); c_write(cfg.keyfile, strlen(cfg.keyfile)); @@ -1651,7 +1668,8 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { if (pktin.type == SSH1_SMSG_STDOUT_DATA || pktin.type == SSH1_SMSG_STDERR_DATA) { long len = GET_32BIT(pktin.body); - c_writedata(pktin.body+4, len); + from_backend(pktin.type == SSH1_SMSG_STDERR_DATA, + pktin.body+4, len); } else if (pktin.type == SSH1_MSG_DISCONNECT) { ssh_state = SSH_STATE_CLOSED; logevent("Received disconnect request"); @@ -1768,7 +1786,7 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) { /* * Utility routine for decoding comma-separated strings in KEXINIT. */ -int in_commasep_string(char *needle, char *haystack, int haylen) { +static int in_commasep_string(char *needle, char *haystack, int haylen) { int needlen = strlen(needle); while (1) { /* @@ -1795,7 +1813,7 @@ int in_commasep_string(char *needle, char *haystack, int haylen) { /* * SSH2 key creation method. */ -void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) { +static void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) { SHA_State s; /* First 20 bytes. */ SHA_Init(&s); @@ -1820,16 +1838,19 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) static int i, len; static char *str; static Bignum e, f, K; - static struct ssh_cipher *cscipher_tobe = NULL; - static struct ssh_cipher *sccipher_tobe = NULL; - static struct ssh_mac *csmac_tobe = NULL; - static struct ssh_mac *scmac_tobe = NULL; - static struct ssh_compress *cscomp_tobe = NULL; - static struct ssh_compress *sccomp_tobe = NULL; + static const struct ssh_mac **maclist; + static int nmacs; + static const struct ssh_cipher *cscipher_tobe = NULL; + static const struct ssh_cipher *sccipher_tobe = NULL; + static const struct ssh_mac *csmac_tobe = NULL; + static const struct ssh_mac *scmac_tobe = NULL; + static const struct ssh_compress *cscomp_tobe = NULL; + static const struct ssh_compress *sccomp_tobe = NULL; static char *hostkeydata, *sigdata, *keystr, *fingerprint; static int hostkeylen, siglen; static unsigned char exchange_hash[20]; static unsigned char keyspace[40]; + static const struct ssh_cipher *preferred_cipher; crBegin; random_init(); @@ -1838,17 +1859,25 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) * Set up the preferred cipher. */ if (cfg.cipher == CIPHER_BLOWFISH) { - ciphers[0] = &ssh_blowfish_ssh2; + preferred_cipher = &ssh_blowfish_ssh2; } else if (cfg.cipher == CIPHER_DES) { logevent("Single DES not supported in SSH2; using 3DES"); - ciphers[0] = &ssh_3des_ssh2; + preferred_cipher = &ssh_3des_ssh2; } else if (cfg.cipher == CIPHER_3DES) { - ciphers[0] = &ssh_3des_ssh2; + preferred_cipher = &ssh_3des_ssh2; } else { /* Shouldn't happen, but we do want to initialise to _something_. */ - ciphers[0] = &ssh_3des_ssh2; + preferred_cipher = &ssh_3des_ssh2; } + /* + * Be prepared to work around the buggy MAC problem. + */ + if (cfg.buggymac) + maclist = buggymacs, nmacs = lenof(buggymacs); + else + maclist = macs, nmacs = lenof(macs); + begin_key_exchange: /* * Construct and send our key exchange packet. @@ -1872,30 +1901,32 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) } /* List client->server encryption algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(ciphers); i++) { - ssh2_pkt_addstring_str(ciphers[i]->name); - if (i < lenof(ciphers)-1) + for (i = 0; i < lenof(ciphers)+1; i++) { + const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; + ssh2_pkt_addstring_str(c->name); + if (i < lenof(ciphers)) ssh2_pkt_addstring_str(","); } /* List server->client encryption algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(ciphers); i++) { - ssh2_pkt_addstring_str(ciphers[i]->name); - if (i < lenof(ciphers)-1) + for (i = 0; i < lenof(ciphers)+1; i++) { + const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; + ssh2_pkt_addstring_str(c->name); + if (i < lenof(ciphers)) ssh2_pkt_addstring_str(","); } /* List client->server MAC algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(macs); i++) { - ssh2_pkt_addstring_str(macs[i]->name); - if (i < lenof(macs)-1) + for (i = 0; i < nmacs; i++) { + ssh2_pkt_addstring_str(maclist[i]->name); + if (i < nmacs-1) ssh2_pkt_addstring_str(","); } /* List server->client MAC algorithms. */ ssh2_pkt_addstring_start(); - for (i = 0; i < lenof(macs); i++) { - ssh2_pkt_addstring_str(macs[i]->name); - if (i < lenof(macs)-1) + for (i = 0; i < nmacs; i++) { + ssh2_pkt_addstring_str(maclist[i]->name); + if (i < nmacs-1) ssh2_pkt_addstring_str(","); } /* List client->server compression algorithms. */ @@ -1952,30 +1983,32 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) } } ssh2_pkt_getstring(&str, &len); /* client->server cipher */ - for (i = 0; i < lenof(ciphers); i++) { - if (in_commasep_string(ciphers[i]->name, str, len)) { - cscipher_tobe = ciphers[i]; + for (i = 0; i < lenof(ciphers)+1; i++) { + const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; + if (in_commasep_string(c->name, str, len)) { + cscipher_tobe = c; break; } } ssh2_pkt_getstring(&str, &len); /* server->client cipher */ - for (i = 0; i < lenof(ciphers); i++) { - if (in_commasep_string(ciphers[i]->name, str, len)) { - sccipher_tobe = ciphers[i]; + for (i = 0; i < lenof(ciphers)+1; i++) { + const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1]; + if (in_commasep_string(c->name, str, len)) { + sccipher_tobe = c; break; } } ssh2_pkt_getstring(&str, &len); /* client->server mac */ - for (i = 0; i < lenof(macs); i++) { - if (in_commasep_string(macs[i]->name, str, len)) { - csmac_tobe = macs[i]; + for (i = 0; i < nmacs; i++) { + if (in_commasep_string(maclist[i]->name, str, len)) { + csmac_tobe = maclist[i]; break; } } ssh2_pkt_getstring(&str, &len); /* server->client mac */ - for (i = 0; i < lenof(macs); i++) { - if (in_commasep_string(macs[i]->name, str, len)) { - scmac_tobe = macs[i]; + for (i = 0; i < nmacs; i++) { + if (in_commasep_string(maclist[i]->name, str, len)) { + scmac_tobe = maclist[i]; break; } } @@ -2056,7 +2089,8 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt) */ keystr = hostkey->fmtkey(); fingerprint = hostkey->fingerprint(); - verify_ssh_host_key(savedhost, hostkey->keytype, keystr, fingerprint); + verify_ssh_host_key(savedhost, savedport, hostkey->keytype, + keystr, fingerprint); logevent("Host key fingerprint is:"); logevent(fingerprint); free(fingerprint); @@ -2184,9 +2218,9 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) } } - if (!(flags & FLAG_INTERACTIVE)) { + if (ssh_get_password) { char prompt[200]; - sprintf(prompt, "%.90s@%.90s's password: ", cfg.username, savedhost); + sprintf(prompt, "%.90s@%.90s's password: ", username, savedhost); if (!ssh_get_password(prompt, password, sizeof(password))) { /* * get_password failed to get a password (for @@ -2261,7 +2295,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); ssh2_pkt_addstring("session"); ssh2_pkt_adduint32(mainchan->localid); - ssh2_pkt_adduint32(0x7FFFFFFFUL); /* our window size */ + ssh2_pkt_adduint32(0x8000UL); /* our window size */ ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */ ssh2_pkt_send(); crWaitUntilV(ispkt); @@ -2375,7 +2409,8 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) continue; /* extended but not stderr */ ssh2_pkt_getstring(&data, &length); if (data) { - c_writedata(data, length); + from_backend(pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA, + data, length); /* * Enlarge the window again at the remote side, * just in case it ever runs down and they fail @@ -2405,6 +2440,9 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) logevent("All channels closed. Disconnecting"); ssh2_pkt_init(SSH2_MSG_DISCONNECT); ssh2_pkt_send(); + ssh_state = SSH_STATE_CLOSED; + closesocket(s); + s = INVALID_SOCKET; } continue; /* remote sends close; ignore (FIXME) */ } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) { @@ -2597,6 +2635,14 @@ static void ssh_special (Telnet_Special code) { ssh2_pkt_send(); } logevent("Sent EOF message"); + } else if (code == TS_PING) { + if (ssh_version == 1) { + send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END); + } else { + ssh2_pkt_init(SSH2_MSG_IGNORE); + ssh2_pkt_addstring_start(); + ssh2_pkt_send(); + } } else { /* do nothing */ } @@ -2613,5 +2659,6 @@ Backend ssh_backend = { ssh_size, ssh_special, ssh_socket, - ssh_sendok + ssh_sendok, + 22 };