version 1.5.2.1, 2001/09/27 19:03:54 |
version 1.5.2.2, 2002/03/09 00:20:44 |
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{ |
{ |
Buffer b; |
Buffer b; |
static u_char digest[EVP_MAX_MD_SIZE]; |
static u_char digest[EVP_MAX_MD_SIZE]; |
EVP_MD *evp_md = EVP_sha1(); |
const EVP_MD *evp_md = EVP_sha1(); |
EVP_MD_CTX md; |
EVP_MD_CTX md; |
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buffer_init(&b); |
buffer_init(&b); |
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buffer_free(&b); |
buffer_free(&b); |
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#ifdef DEBUG_KEXDH |
#ifdef DEBUG_KEXDH |
dump_digest("hash", digest, evp_md->md_size); |
dump_digest("hash", digest, EVP_MD_size(evp_md)); |
#endif |
#endif |
return digest; |
return digest; |
} |
} |
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Key *server_host_key; |
Key *server_host_key; |
u_char *kbuf, *hash, *signature = NULL, *server_host_key_blob = NULL; |
u_char *kbuf, *hash, *signature = NULL, *server_host_key_blob = NULL; |
u_int klen, kout, slen, sbloblen; |
u_int klen, kout, slen, sbloblen; |
int dlen, plen, min, max, nbits; |
int min, max, nbits; |
DH *dh; |
DH *dh; |
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nbits = dh_estimate(kex->we_need * 8); |
nbits = dh_estimate(kex->we_need * 8); |
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packet_send(); |
packet_send(); |
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debug("expecting SSH2_MSG_KEX_DH_GEX_GROUP"); |
debug("expecting SSH2_MSG_KEX_DH_GEX_GROUP"); |
packet_read_expect(&plen, SSH2_MSG_KEX_DH_GEX_GROUP); |
packet_read_expect(SSH2_MSG_KEX_DH_GEX_GROUP); |
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if ((p = BN_new()) == NULL) |
if ((p = BN_new()) == NULL) |
fatal("BN_new"); |
fatal("BN_new"); |
packet_get_bignum2(p, &dlen); |
packet_get_bignum2(p); |
if ((g = BN_new()) == NULL) |
if ((g = BN_new()) == NULL) |
fatal("BN_new"); |
fatal("BN_new"); |
packet_get_bignum2(g, &dlen); |
packet_get_bignum2(g); |
packet_done(); |
packet_check_eom(); |
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if (BN_num_bits(p) < min || BN_num_bits(p) > max) |
if (BN_num_bits(p) < min || BN_num_bits(p) > max) |
fatal("DH_GEX group out of range: %d !< %d !< %d", |
fatal("DH_GEX group out of range: %d !< %d !< %d", |
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packet_send(); |
packet_send(); |
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debug("expecting SSH2_MSG_KEX_DH_GEX_REPLY"); |
debug("expecting SSH2_MSG_KEX_DH_GEX_REPLY"); |
packet_read_expect(&plen, SSH2_MSG_KEX_DH_GEX_REPLY); |
packet_read_expect(SSH2_MSG_KEX_DH_GEX_REPLY); |
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/* key, cert */ |
/* key, cert */ |
server_host_key_blob = packet_get_string(&sbloblen); |
server_host_key_blob = packet_get_string(&sbloblen); |
server_host_key = key_from_blob(server_host_key_blob, sbloblen); |
server_host_key = key_from_blob(server_host_key_blob, sbloblen); |
if (server_host_key == NULL) |
if (server_host_key == NULL) |
fatal("cannot decode server_host_key_blob"); |
fatal("cannot decode server_host_key_blob"); |
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if (server_host_key->type != kex->hostkey_type) |
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fatal("type mismatch for decoded server_host_key_blob"); |
if (kex->verify_host_key == NULL) |
if (kex->verify_host_key == NULL) |
fatal("cannot verify server_host_key"); |
fatal("cannot verify server_host_key"); |
if (kex->verify_host_key(server_host_key) == -1) |
if (kex->verify_host_key(server_host_key) == -1) |
fatal("server_host_key verification failed"); |
fatal("server_host_key verification failed"); |
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/* DH paramter f, server public DH key */ |
/* DH paramter f, server public DH key */ |
dh_server_pub = BN_new(); |
if ((dh_server_pub = BN_new()) == NULL) |
if (dh_server_pub == NULL) |
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fatal("dh_server_pub == NULL"); |
fatal("dh_server_pub == NULL"); |
packet_get_bignum2(dh_server_pub, &dlen); |
packet_get_bignum2(dh_server_pub); |
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#ifdef DEBUG_KEXDH |
#ifdef DEBUG_KEXDH |
fprintf(stderr, "dh_server_pub= "); |
fprintf(stderr, "dh_server_pub= "); |
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/* signed H */ |
/* signed H */ |
signature = packet_get_string(&slen); |
signature = packet_get_string(&slen); |
packet_done(); |
packet_check_eom(); |
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if (!dh_pub_is_valid(dh, dh_server_pub)) |
if (!dh_pub_is_valid(dh, dh_server_pub)) |
packet_disconnect("bad server public DH value"); |
packet_disconnect("bad server public DH value"); |
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#ifdef DEBUG_KEXDH |
#ifdef DEBUG_KEXDH |
dump_digest("shared secret", kbuf, kout); |
dump_digest("shared secret", kbuf, kout); |
#endif |
#endif |
shared_secret = BN_new(); |
if ((shared_secret = BN_new()) == NULL) |
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fatal("kexgex_client: BN_new failed"); |
BN_bin2bn(kbuf, kout, shared_secret); |
BN_bin2bn(kbuf, kout, shared_secret); |
memset(kbuf, 0, klen); |
memset(kbuf, 0, klen); |
xfree(kbuf); |
xfree(kbuf); |
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/* have keys, free DH */ |
/* have keys, free DH */ |
DH_free(dh); |
DH_free(dh); |
xfree(server_host_key_blob); |
xfree(server_host_key_blob); |
BN_free(dh_server_pub); |
BN_clear_free(dh_server_pub); |
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if (key_verify(server_host_key, signature, slen, hash, 20) != 1) |
if (key_verify(server_host_key, signature, slen, hash, 20) != 1) |
fatal("key_verify failed for server_host_key"); |
fatal("key_verify failed for server_host_key"); |
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Key *server_host_key; |
Key *server_host_key; |
DH *dh = dh; |
DH *dh = dh; |
u_char *kbuf, *hash, *signature = NULL, *server_host_key_blob = NULL; |
u_char *kbuf, *hash, *signature = NULL, *server_host_key_blob = NULL; |
u_int sbloblen, klen, kout; |
u_int sbloblen, klen, kout, slen; |
int min = -1, max = -1, nbits = -1, type, plen, dlen, slen; |
int min = -1, max = -1, nbits = -1, type; |
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if (kex->load_host_key == NULL) |
if (kex->load_host_key == NULL) |
fatal("Cannot load hostkey"); |
fatal("Cannot load hostkey"); |
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if (server_host_key == NULL) |
if (server_host_key == NULL) |
fatal("Unsupported hostkey type %d", kex->hostkey_type); |
fatal("Unsupported hostkey type %d", kex->hostkey_type); |
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type = packet_read(&plen); |
type = packet_read(); |
switch(type){ |
switch (type) { |
case SSH2_MSG_KEX_DH_GEX_REQUEST: |
case SSH2_MSG_KEX_DH_GEX_REQUEST: |
debug("SSH2_MSG_KEX_DH_GEX_REQUEST received"); |
debug("SSH2_MSG_KEX_DH_GEX_REQUEST received"); |
min = packet_get_int(); |
min = packet_get_int(); |
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default: |
default: |
fatal("protocol error during kex, no DH_GEX_REQUEST: %d", type); |
fatal("protocol error during kex, no DH_GEX_REQUEST: %d", type); |
} |
} |
packet_done(); |
packet_check_eom(); |
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if (max < min || nbits < min || max < nbits) |
if (max < min || nbits < min || max < nbits) |
fatal("DH_GEX_REQUEST, bad parameters: %d !< %d !< %d", |
fatal("DH_GEX_REQUEST, bad parameters: %d !< %d !< %d", |
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dh_gen_key(dh, kex->we_need * 8); |
dh_gen_key(dh, kex->we_need * 8); |
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debug("expecting SSH2_MSG_KEX_DH_GEX_INIT"); |
debug("expecting SSH2_MSG_KEX_DH_GEX_INIT"); |
packet_read_expect(&plen, SSH2_MSG_KEX_DH_GEX_INIT); |
packet_read_expect(SSH2_MSG_KEX_DH_GEX_INIT); |
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/* key, cert */ |
/* key, cert */ |
dh_client_pub = BN_new(); |
if ((dh_client_pub = BN_new()) == NULL) |
if (dh_client_pub == NULL) |
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fatal("dh_client_pub == NULL"); |
fatal("dh_client_pub == NULL"); |
packet_get_bignum2(dh_client_pub, &dlen); |
packet_get_bignum2(dh_client_pub); |
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packet_check_eom(); |
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#ifdef DEBUG_KEXDH |
#ifdef DEBUG_KEXDH |
fprintf(stderr, "dh_client_pub= "); |
fprintf(stderr, "dh_client_pub= "); |
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#ifdef DEBUG_KEXDH |
#ifdef DEBUG_KEXDH |
dump_digest("shared secret", kbuf, kout); |
dump_digest("shared secret", kbuf, kout); |
#endif |
#endif |
shared_secret = BN_new(); |
if ((shared_secret = BN_new()) == NULL) |
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fatal("kexgex_server: BN_new failed"); |
BN_bin2bn(kbuf, kout, shared_secret); |
BN_bin2bn(kbuf, kout, shared_secret); |
memset(kbuf, 0, klen); |
memset(kbuf, 0, klen); |
xfree(kbuf); |
xfree(kbuf); |
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dh->pub_key, |
dh->pub_key, |
shared_secret |
shared_secret |
); |
); |
BN_free(dh_client_pub); |
BN_clear_free(dh_client_pub); |
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/* save session id := H */ |
/* save session id := H */ |
/* XXX hashlen depends on KEX */ |
/* XXX hashlen depends on KEX */ |