X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/70887be9ad821c22faf52c87597a707a8320a8cf..e557416818242c2e8b14ec03d321740fd83619e4:/ssh.c diff --git a/ssh.c b/ssh.c index 65f0075c..ae41a80e 100644 --- a/ssh.c +++ b/ssh.c @@ -19,30 +19,41 @@ if (IS_SCP && (scp_flags & SCP_VERBOSE) != 0) \ fprintf(stderr, "%s\n", s); } -#define SSH_MSG_DISCONNECT 1 -#define SSH_SMSG_PUBLIC_KEY 2 -#define SSH_CMSG_SESSION_KEY 3 -#define SSH_CMSG_USER 4 -#define SSH_CMSG_AUTH_PASSWORD 9 -#define SSH_CMSG_REQUEST_PTY 10 -#define SSH_CMSG_WINDOW_SIZE 11 -#define SSH_CMSG_EXEC_SHELL 12 -#define SSH_CMSG_EXEC_CMD 13 -#define SSH_SMSG_SUCCESS 14 -#define SSH_SMSG_FAILURE 15 -#define SSH_CMSG_STDIN_DATA 16 -#define SSH_SMSG_STDOUT_DATA 17 -#define SSH_SMSG_STDERR_DATA 18 -#define SSH_CMSG_EOF 19 -#define SSH_SMSG_EXIT_STATUS 20 -#define SSH_CMSG_EXIT_CONFIRMATION 33 -#define SSH_MSG_IGNORE 32 -#define SSH_MSG_DEBUG 36 -#define SSH_CMSG_AUTH_TIS 39 -#define SSH_SMSG_AUTH_TIS_CHALLENGE 40 -#define SSH_CMSG_AUTH_TIS_RESPONSE 41 - -#define SSH_AUTH_TIS 5 +#define SSH1_MSG_DISCONNECT 1 +#define SSH1_SMSG_PUBLIC_KEY 2 +#define SSH1_CMSG_SESSION_KEY 3 +#define SSH1_CMSG_USER 4 +#define SSH1_CMSG_AUTH_PASSWORD 9 +#define SSH1_CMSG_REQUEST_PTY 10 +#define SSH1_CMSG_WINDOW_SIZE 11 +#define SSH1_CMSG_EXEC_SHELL 12 +#define SSH1_CMSG_EXEC_CMD 13 +#define SSH1_SMSG_SUCCESS 14 +#define SSH1_SMSG_FAILURE 15 +#define SSH1_CMSG_STDIN_DATA 16 +#define SSH1_SMSG_STDOUT_DATA 17 +#define SSH1_SMSG_STDERR_DATA 18 +#define SSH1_CMSG_EOF 19 +#define SSH1_SMSG_EXIT_STATUS 20 +#define SSH1_CMSG_EXIT_CONFIRMATION 33 +#define SSH1_MSG_IGNORE 32 +#define SSH1_MSG_DEBUG 36 +#define SSH1_CMSG_AUTH_TIS 39 +#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 +#define SSH1_CMSG_AUTH_TIS_RESPONSE 41 + +#define SSH1_AUTH_TIS 5 + +#define SSH2_MSG_DISCONNECT 1 +#define SSH2_MSG_IGNORE 2 +#define SSH2_MSG_UNIMPLEMENTED 3 +#define SSH2_MSG_DEBUG 4 +#define SSH2_MSG_SERVICE_REQUEST 5 +#define SSH2_MSG_SERVICE_ACCEPT 6 +#define SSH2_MSG_KEXINIT 20 +#define SSH2_MSG_NEWKEYS 21 +#define SSH2_MSG_KEXDH_INIT 30 +#define SSH2_MSG_KEXDH_REPLY 31 #define GET_32BIT(cp) \ (((unsigned long)(unsigned char)(cp)[0] << 24) | \ @@ -76,10 +87,48 @@ enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR }; #define crStopV do{ crLine = 0; return; }while(0) #define crWaitUntil(c) do { crReturn(0); } while (!(c)) +extern struct ssh_cipher ssh_3des; +extern struct ssh_cipher ssh_des; +extern struct ssh_cipher ssh_blowfish; + +/* for ssh 2; we miss out single-DES because it isn't supported */ +struct ssh_cipher *ciphers[] = { &ssh_3des, &ssh_blowfish }; + +extern struct ssh_kex ssh_diffiehellman; +struct ssh_kex *kex_algs[] = { &ssh_diffiehellman }; + +extern struct ssh_hostkey ssh_dss; +struct ssh_hostkey *hostkey_algs[] = { &ssh_dss }; + +extern struct ssh_mac ssh_sha1; + +SHA_State exhash; + +static void nullmac_sesskey(unsigned char *key, int len) { } +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 = { + nullmac_sesskey, nullmac_generate, nullmac_verify, "none", 0 +}; +struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none }; + +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 scp_flags = 0; int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL; @@ -137,25 +186,29 @@ struct Packet { 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 void ssh_protocol(unsigned char *in, int inlen, int ispkt); +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. - * Decihper and verify the packet when it is completely read. - * Drop SSH_MSG_DEBUG and SSH_MSG_IGNORE packets. + * Decipher and verify the packet when it is completely read. + * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets. * Update the *data and *datalen variables. * Return the additional nr of bytes needed, or 0 when * a complete packet is available. */ -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; @@ -188,15 +241,8 @@ next_packet: if (pktin.maxlen < biglen) { pktin.maxlen = biglen; -#ifdef MSCRYPTOAPI - /* Allocate enough buffer space for extra block - * for MS CryptEncrypt() */ - pktin.data = (pktin.data == NULL ? malloc(biglen+8) : - realloc(pktin.data, biglen+8)); -#else - pktin.data = (pktin.data == NULL ? malloc(biglen) : - realloc(pktin.data, biglen)); -#endif + pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) : + realloc(pktin.data, biglen+APIEXTRA)); if (!pktin.data) fatalbox("Out of memory"); } @@ -229,16 +275,16 @@ next_packet: fatalbox("Incorrect CRC received on packet"); } - if (pktin.type == SSH_SMSG_STDOUT_DATA || - pktin.type == SSH_SMSG_STDERR_DATA || - pktin.type == SSH_MSG_DEBUG || - pktin.type == SSH_SMSG_AUTH_TIS_CHALLENGE) { + if (pktin.type == SSH1_SMSG_STDOUT_DATA || + pktin.type == SSH1_SMSG_STDERR_DATA || + pktin.type == SSH1_MSG_DEBUG || + pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE) { long strlen = GET_32BIT(pktin.body); if (strlen + 4 != pktin.length) fatalbox("Received data packet with bogus string length"); } - if (pktin.type == SSH_MSG_DEBUG) { + if (pktin.type == SSH1_MSG_DEBUG) { /* log debug message */ char buf[80]; int strlen = GET_32BIT(pktin.body); @@ -248,7 +294,7 @@ next_packet: buf[8+strlen] = '\0'; logevent(buf); goto next_packet; - } else if (pktin.type == SSH_MSG_IGNORE) { + } else if (pktin.type == SSH1_MSG_IGNORE) { /* do nothing */ goto next_packet; } @@ -256,6 +302,118 @@ next_packet: crFinish(0); } +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; + + crBegin; + +next_packet: + + pktin.type = 0; + pktin.length = 0; + + if (cipher) + cipherblk = cipher->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)); + if (!pktin.data) + fatalbox("Out of memory"); + } + + /* + * Acquire and decrypt the first block of the packet. This will + * contain the length and padding details. + */ + for (i = len = 0; i < cipherblk; i++) { + while ((*datalen) == 0) + crReturn(cipherblk-i); + pktin.data[i] = *(*data)++; + (*datalen)--; + } +#ifdef FWHACK + if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */ + /* FIXME */ + } +#endif + if (sccipher) + sccipher->decrypt(pktin.data, cipherblk); + + /* + * Now get the length and padding figures. + */ + len = GET_32BIT(pktin.data); + pad = pktin.data[4]; + + /* + * This enables us to deduce the payload length. + */ + payload = len - pad - 1; + + pktin.length = payload + 5; + + /* + * So now we can work out the total packet length. + */ + packetlen = len + 4; + maclen = scmac ? scmac->len : 0; + + /* + * Adjust memory allocation if packet is too big. + */ + if (pktin.maxlen < packetlen) { + pktin.maxlen = packetlen; + pktin.data = (pktin.data == NULL ? malloc(packetlen+APIEXTRA) : + realloc(pktin.data, packetlen+APIEXTRA)); + if (!pktin.data) + fatalbox("Out of memory"); + } + + /* + * Read and decrypt the remainder of the packet. + */ + for (i = cipherblk; i < packetlen + maclen; i++) { + while ((*datalen) == 0) + crReturn(packetlen + maclen - i); + pktin.data[i] = *(*data)++; + (*datalen)--; + } + /* Decrypt everything _except_ the MAC. */ + if (sccipher) + sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk); + + /* + * Check the MAC. + */ + if (scmac && !scmac->verify(pktin.data, incoming_sequence++, len+4)) + fatalbox("Incorrect MAC received on packet"); + + pktin.savedpos = 6; + pktin.type = pktin.data[5]; +#if 0 + debug(("Got packet len=%d pad=%d\r\n", len, pad)); + for (i = 0; i < payload; i++) + debug((" %02x", (unsigned char)pktin.data[i])); + debug(("\r\n")); +#endif + + /* + * FIXME: handle IGNORE and DEBUG messages. + */ + + crFinish(0); +} + static void ssh_gotdata(unsigned char *data, int datalen) { while (datalen > 0) { @@ -509,6 +667,24 @@ static int ssh_versioncmp(char *a, char *b) { return 0; } + +/* + * Utility routine for putting an SSH-protocol `string' into a SHA + * state. + */ +#include +void sha_string(SHA_State *s, void *str, int len) { + unsigned char lenblk[4]; +static FILE *fp; + PUT_32BIT(lenblk, len); +if (!fp) fp = fopen("h:\\statham\\windows\\putty\\data","wb"); +fwrite(lenblk, 4, 1, fp); + SHA_Bytes(s, lenblk, 4); +fwrite(str, len, 1, fp); +fflush(fp); + SHA_Bytes(s, str, len); +} + static int do_ssh_init(void) { char c, *vsp; char version[10]; @@ -554,19 +730,45 @@ static int do_ssh_init(void) { vlog[strcspn(vlog, "\r\n")] = '\0'; logevent(vlog); - sprintf(vstring, "SSH-%s-PuTTY\n", - (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5")); - sprintf(vlog, "We claim version: %s", vstring); - vlog[strcspn(vlog, "\r\n")] = '\0'; - logevent(vlog); - s_write(vstring, strlen(vstring)); + if (ssh_versioncmp(version, "1.99") >= 0) { + /* + * This is a v2 server. Begin v2 protocol. + */ + char *verstring = "SSH-2.0-PuTTY"; + SHA_Init(&exhash); + /* + * Hash our version string and their version string. + */ + sha_string(&exhash, verstring, strlen(verstring)); + sha_string(&exhash, vstring, strcspn(vstring, "\r\n")); + sprintf(vstring, "%s\n", verstring); + sprintf(vlog, "We claim version: %s", verstring); + logevent(vlog); + logevent("Using SSH protocol version 2"); + s_write(vstring, strlen(vstring)); + ssh_protocol = ssh2_protocol; + s_rdpkt = ssh2_rdpkt; + } else { + /* + * This is a v1 server. Begin v1 protocol. + */ + sprintf(vstring, "SSH-%s-PuTTY\n", + (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5")); + sprintf(vlog, "We claim version: %s", vstring); + vlog[strcspn(vlog, "\r\n")] = '\0'; + logevent(vlog); + logevent("Using SSH protocol version 1"); + s_write(vstring, strlen(vstring)); + ssh_protocol = ssh1_protocol; + s_rdpkt = ssh1_rdpkt; + } return 1; } /* * Handle the key exchange and user authentication phases. */ -static int do_ssh_login(unsigned char *in, int inlen, int ispkt) +static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) { int i, j, len; unsigned char session_id[16]; @@ -577,15 +779,11 @@ static int do_ssh_login(unsigned char *in, int inlen, int ispkt) static unsigned long supported_ciphers_mask, supported_auths_mask; int cipher_type; - extern struct ssh_cipher ssh_3des; - extern struct ssh_cipher ssh_des; - extern struct ssh_cipher ssh_blowfish; - crBegin; if (!ispkt) crWaitUntil(ispkt); - if (pktin.type != SSH_SMSG_PUBLIC_KEY) + if (pktin.type != SSH1_SMSG_PUBLIC_KEY) fatalbox("Public key packet not received"); logevent("Received public keys"); @@ -677,7 +875,7 @@ static int do_ssh_login(unsigned char *in, int inlen, int ispkt) case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break; } - send_packet(SSH_CMSG_SESSION_KEY, + send_packet(SSH1_CMSG_SESSION_KEY, PKT_CHAR, cipher_type, PKT_DATA, cookie, 8, PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF, @@ -696,7 +894,7 @@ static int do_ssh_login(unsigned char *in, int inlen, int ispkt) crWaitUntil(ispkt); - if (pktin.type != SSH_SMSG_SUCCESS) + if (pktin.type != SSH1_SMSG_SUCCESS) fatalbox("Encryption not successfully enabled"); logevent("Successfully started encryption"); @@ -752,7 +950,7 @@ static int do_ssh_login(unsigned char *in, int inlen, int ispkt) } } - send_packet(SSH_CMSG_USER, PKT_STR, username, PKT_END); + send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END); { char userlog[20+sizeof(username)]; sprintf(userlog, "Sent username \"%s\"", username); @@ -762,7 +960,7 @@ static int do_ssh_login(unsigned char *in, int inlen, int ispkt) crWaitUntil(ispkt); - while (pktin.type == SSH_SMSG_FAILURE) { + while (pktin.type == SSH1_SMSG_FAILURE) { static char password[100]; static int pos; static char c; @@ -772,7 +970,7 @@ static int do_ssh_login(unsigned char *in, int inlen, int ispkt) * Show password prompt, having first obtained it via a TIS * exchange if we're doing TIS authentication. */ - pwpkt_type = SSH_CMSG_AUTH_PASSWORD; + pwpkt_type = SSH1_CMSG_AUTH_PASSWORD; if (IS_SCP) { char prompt[200]; @@ -790,14 +988,14 @@ static int do_ssh_login(unsigned char *in, int inlen, int ispkt) } } else { - if (pktin.type == SSH_SMSG_FAILURE && + if (pktin.type == SSH1_SMSG_FAILURE && cfg.try_tis_auth && - (supported_auths_mask & (1<> 8) & 0xFF; + p[i*2+2] = (b[n-i] ) & 0xFF; + } + i = 0; + while (p[i] == 0 && (p[i+1] & 0x80) == 0) + i++; + memmove(p, p+i, n*2+1-i); + *len = n*2+1-i; + return p; +} +void ssh2_pkt_addmp(Bignum b) { + unsigned char *p; + int len; + p = ssh2_mpint_fmt(b, &len); + ssh2_pkt_addstring_start(); + ssh2_pkt_addstring_data(p, len); + free(p); +} +void ssh2_pkt_send(void) { + int cipherblk, maclen, padding, i; + unsigned long outgoing_sequence = 0; + + /* + * Add padding. At least four bytes, and must also bring total + * length (minus MAC) up to a multiple of the block size. + */ + cipherblk = cipher ? cipher->blksize : 8; /* block size */ + cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */ + padding = 4; + padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk; + pktout.data[4] = padding; + for (i = 0; i < padding; i++) + pktout.data[pktout.length + i] = random_byte(); + PUT_32BIT(pktout.data, pktout.length + padding - 4); + if (csmac) + csmac->generate(pktout.data, outgoing_sequence++, + pktout.length + padding); + if (cscipher) + cscipher->encrypt(pktout.data, pktout.length + padding); + maclen = csmac ? csmac->len : 0; +#if 0 + debug(("Sending packet len=%d\r\n", pktout.length+padding+maclen)); + for (i = 0; i < pktout.length+padding+maclen; i++) + debug((" %02x", (unsigned char)pktout.data[i])); + debug(("\r\n")); +#endif + s_write(pktout.data, pktout.length + padding + maclen); +} + +void sha_mpint(SHA_State *s, Bignum b) { + unsigned char *p; + int len; + p = ssh2_mpint_fmt(b, &len); + sha_string(s, p, len); + free(p); +} + +/* + * SSH2 packet decode functions. + */ +void ssh2_pkt_getstring(char **p, int *length) { + *p = NULL; + if (pktin.length - pktin.savedpos < 4) + return; + *length = GET_32BIT(pktin.data+pktin.savedpos); + pktin.savedpos += 4; + if (pktin.length - pktin.savedpos < *length) + return; + *p = pktin.data+pktin.savedpos; + pktin.savedpos += *length; +} +Bignum ssh2_pkt_getmp(void) { + char *p; + int i, j, length; + Bignum b; + + ssh2_pkt_getstring(&p, &length); + if (!p) + return NULL; + if (p[0] & 0x80) + fatalbox("internal error: Can't handle negative mpints"); + b = newbn((length+1)/2); + for (i = 0; i < length; i++) { + j = length - 1 - i; + if (j & 1) + b[j/2+1] |= ((unsigned char)p[i]) << 8; + else + b[j/2+1] |= ((unsigned char)p[i]); + } + return b; +} + +void bndebug(char *string, Bignum b) { + unsigned char *p; + int i, len; + p = ssh2_mpint_fmt(b, &len); + debug(("%s", string)); + for (i = 0; i < len; i++) + debug((" %02x", p[i])); + debug(("\r\n")); + free(p); +} + +/* + * Utility routine for decoding comma-separated strings in KEXINIT. + */ +int in_commasep_string(char *needle, char *haystack, int haylen) { + int 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 */ + } +} + +/* + * Handle the SSH2 key exchange phase. + */ +static int do_ssh2_kex(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 char *hostkeydata, *sigdata; + static int hostkeylen, siglen; + static unsigned char exchange_hash[20]; + + crBegin; + + /* + * Construct and send our key exchange packet. + */ + ssh2_pkt_init(SSH2_MSG_KEXINIT); + for (i = 0; i < 16; i++) + ssh2_pkt_addbyte((unsigned char)random_byte()); + /* List key exchange algorithms. */ + ssh2_pkt_addstring_start(); + for (i = 0; i < lenof(kex_algs); i++) { + ssh2_pkt_addstring_str(kex_algs[i]->name); + if (i < lenof(kex_algs)-1) + ssh2_pkt_addstring_str(","); + } + /* List server host key algorithms. */ + ssh2_pkt_addstring_start(); + for (i = 0; i < lenof(hostkey_algs); i++) { + ssh2_pkt_addstring_str(hostkey_algs[i]->name); + if (i < lenof(hostkey_algs)-1) + ssh2_pkt_addstring_str(","); + } + /* 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) + 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) + 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) + 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) + ssh2_pkt_addstring_str(","); + } + /* List client->server compression algorithms. */ + ssh2_pkt_addstring_start(); + for (i = 0; i < lenof(compressions); i++) { + ssh2_pkt_addstring_str(compressions[i]->name); + if (i < lenof(compressions)-1) + ssh2_pkt_addstring_str(","); + } + /* List server->client compression algorithms. */ + ssh2_pkt_addstring_start(); + for (i = 0; i < lenof(compressions); i++) { + ssh2_pkt_addstring_str(compressions[i]->name); + if (i < lenof(compressions)-1) + ssh2_pkt_addstring_str(","); + } + /* List client->server languages. Empty list. */ + ssh2_pkt_addstring_start(); + /* List server->client languages. Empty list. */ + ssh2_pkt_addstring_start(); + /* First KEX packet does _not_ follow, because we're not that brave. */ + ssh2_pkt_addbool(FALSE); + /* Reserved. */ + ssh2_pkt_adduint32(0); + sha_string(&exhash, pktout.data+5, pktout.length-5); + ssh2_pkt_send(); + + if (!ispkt) crWaitUntil(ispkt); + sha_string(&exhash, pktin.data+5, pktin.length-5); + + /* + * Now examine the other side's KEXINIT to see what we're up + * to. + */ + if (pktin.type != SSH2_MSG_KEXINIT) + fatalbox("expected key exchange packet from server"); + kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL; + csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL; + pktin.savedpos += 16; /* skip garbage cookie */ + ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */ + for (i = 0; i < lenof(kex_algs); i++) { + if (in_commasep_string(kex_algs[i]->name, str, len)) { + kex = kex_algs[i]; + break; + } + } + ssh2_pkt_getstring(&str, &len); /* host key algorithms */ + for (i = 0; i < lenof(hostkey_algs); i++) { + if (in_commasep_string(hostkey_algs[i]->name, str, len)) { + hostkey = hostkey_algs[i]; + break; + } + } + 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]; + 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]; + 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]; + 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]; + break; + } + } + ssh2_pkt_getstring(&str, &len); /* client->server compression */ + for (i = 0; i < lenof(compressions); i++) { + if (in_commasep_string(compressions[i]->name, str, len)) { + cscomp_tobe = compressions[i]; + break; + } + } + ssh2_pkt_getstring(&str, &len); /* server->client compression */ + for (i = 0; i < lenof(compressions); i++) { + if (in_commasep_string(compressions[i]->name, str, len)) { + sccomp_tobe = compressions[i]; + break; + } + } + debug(("key exchange is %s\r\n", kex ? kex->name : NULL)); + debug(("host key alg is %s\r\n", hostkey ? hostkey->name : NULL)); + debug(("cscipher alg is %s\r\n", cscipher_tobe ? cscipher_tobe->name : NULL)); + debug(("sccipher alg is %s\r\n", sccipher_tobe ? sccipher_tobe->name : NULL)); + debug(("csmac alg is %s\r\n", csmac_tobe ? csmac_tobe->name : NULL)); + debug(("scmac alg is %s\r\n", scmac_tobe ? scmac_tobe->name : NULL)); + debug(("cscomp alg is %s\r\n", cscomp_tobe ? cscomp_tobe->name : NULL)); + debug(("sccomp alg is %s\r\n", sccomp_tobe ? sccomp_tobe->name : NULL)); + + /* + * Currently we only support Diffie-Hellman and DSS, so let's + * bomb out if those aren't selected. + */ + if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) + fatalbox("internal fault: chaos in SSH 2 transport layer"); + + /* + * Now we begin the fun. Generate and send e for Diffie-Hellman. + */ + e = dh_create_e(); + bndebug("e=", e); + ssh2_pkt_init(SSH2_MSG_KEXDH_INIT); + ssh2_pkt_addmp(e); + ssh2_pkt_send(); + + crWaitUntil(ispkt); + if (pktin.type != SSH2_MSG_KEXDH_REPLY) + fatalbox("expected key exchange packet from server"); + ssh2_pkt_getstring(&hostkeydata, &hostkeylen); + f = ssh2_pkt_getmp(); + bndebug("f=", f); + ssh2_pkt_getstring(&sigdata, &siglen); + + K = dh_find_K(f); + bndebug("K=", K); + + sha_string(&exhash, hostkeydata, hostkeylen); + sha_mpint(&exhash, e); + sha_mpint(&exhash, f); + sha_mpint(&exhash, K); + SHA_Final(&exhash, exchange_hash); + + debug(("Exchange hash is:\r\n")); + for (i = 0; i < 20; i++) + debug((" %02x", exchange_hash[i])); + debug(("\r\n")); + + /* + * FIXME: verify hostkeydata and sigdata. + */ + + crWaitUntil(0); + + crFinish(1); +} + +static void ssh2_protocol(unsigned char *in, int inlen, int ispkt) { + crBegin; + + random_init(); + + while (!do_ssh2_kex(in, inlen, ispkt)) { + crReturnV; + } + + crFinishV; +} + +/* * Called to set up the connection. Will arrange for WM_NETEVENT * messages to be passed to the specified window, whose window * procedure should then call telnet_msg(). @@ -1025,7 +1637,7 @@ static void ssh_size(void) { break; case SSH_STATE_SESSION: if (!cfg.nopty) { - send_packet(SSH_CMSG_WINDOW_SIZE, + send_packet(SSH1_CMSG_WINDOW_SIZE, PKT_INT, rows, PKT_INT, cols, PKT_INT, 0, PKT_INT, 0, PKT_END); } @@ -1102,7 +1714,7 @@ int ssh_scp_recv(unsigned char *buf, int len) get_packet(); if (s == INVALID_SOCKET) return 0; - if (pktin.type == SSH_SMSG_STDOUT_DATA) { + if (pktin.type == SSH1_SMSG_STDOUT_DATA) { int plen = GET_32BIT(pktin.body); if (plen <= to_read) { memcpy(buf, pktin.body + 4, plen); @@ -1114,19 +1726,19 @@ int ssh_scp_recv(unsigned char *buf, int len) pending_input_ptr = pktin.body + 4 + to_read; to_read = 0; } - } else if (pktin.type == SSH_SMSG_STDERR_DATA) { + } else if (pktin.type == SSH1_SMSG_STDERR_DATA) { int plen = GET_32BIT(pktin.body); fwrite(pktin.body + 4, plen, 1, stderr); - } else if (pktin.type == SSH_MSG_DISCONNECT) { + } else if (pktin.type == SSH1_MSG_DISCONNECT) { logevent("Received disconnect request"); - } else if (pktin.type == SSH_SMSG_SUCCESS || - pktin.type == SSH_SMSG_FAILURE) { + } else if (pktin.type == SSH1_SMSG_SUCCESS || + pktin.type == SSH1_SMSG_FAILURE) { /* ignore */ - } else if (pktin.type == SSH_SMSG_EXIT_STATUS) { + } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) { char logbuf[100]; sprintf(logbuf, "Remote exit status: %d", GET_32BIT(pktin.body)); logevent(logbuf); - send_packet(SSH_CMSG_EXIT_CONFIRMATION, PKT_END); + send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END); logevent("Closing connection"); closesocket(s); s = INVALID_SOCKET; @@ -1148,7 +1760,7 @@ void ssh_scp_send(unsigned char *buf, int len) assert(IS_SCP); if (s == INVALID_SOCKET) return; - send_packet(SSH_CMSG_STDIN_DATA, + send_packet(SSH1_CMSG_STDIN_DATA, PKT_INT, len, PKT_DATA, buf, len, PKT_END); } @@ -1161,7 +1773,7 @@ void ssh_scp_send_eof(void) assert(IS_SCP); if (s == INVALID_SOCKET) return; - send_packet(SSH_CMSG_EOF, PKT_END); + send_packet(SSH1_CMSG_EOF, PKT_END); } /* @@ -1195,7 +1807,7 @@ char *ssh_scp_init(char *host, int port, char *cmd, char **realhost) get_packet(); if (s == INVALID_SOCKET) return "Connection closed by remote host"; - } while (!do_ssh_login(NULL, 0, 1)); + } while (!do_ssh1_login(NULL, 0, 1)); if (ssh_state == SSH_STATE_CLOSED) { closesocket(s); @@ -1206,7 +1818,7 @@ char *ssh_scp_init(char *host, int port, char *cmd, char **realhost) /* Execute command */ sprintf(buf, "Sending command: %.100s", cmd); logevent(buf); - send_packet(SSH_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END); + send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END); return NULL; }