|
Lines 44-49
RCSID("$OpenBSD: kex.c,v 1.60 2004/06/21
Link Here
|
| 44 |
|
44 |
|
| 45 |
#define KEX_COOKIE_LEN 16 |
45 |
#define KEX_COOKIE_LEN 16 |
| 46 |
|
46 |
|
|
|
47 |
extern const EVP_MD *evp_ssh_sha512(void); |
| 48 |
|
| 47 |
/* prototype */ |
49 |
/* prototype */ |
| 48 |
static void kex_kexinit_finish(Kex *); |
50 |
static void kex_kexinit_finish(Kex *); |
| 49 |
static void kex_choose_conf(Kex *); |
51 |
static void kex_choose_conf(Kex *); |
|
Lines 295-302
choose_kex(Kex *k, char *client, char *s
Link Here
|
| 295 |
k->kex_type = KEX_DH_GRP1_SHA1; |
297 |
k->kex_type = KEX_DH_GRP1_SHA1; |
| 296 |
} else if (strcmp(k->name, KEX_DH14) == 0) { |
298 |
} else if (strcmp(k->name, KEX_DH14) == 0) { |
| 297 |
k->kex_type = KEX_DH_GRP14_SHA1; |
299 |
k->kex_type = KEX_DH_GRP14_SHA1; |
| 298 |
} else if (strcmp(k->name, KEX_DHGEX) == 0) { |
300 |
} else if (strcmp(k->name, KEX_DHGEX_SHA1) == 0) { |
| 299 |
k->kex_type = KEX_DH_GEX_SHA1; |
301 |
k->kex_type = KEX_DH_GEX_SHA1; |
|
|
302 |
} else if (strcmp(k->name, KEX_DHGEX_SHA512) == 0) { |
| 303 |
k->kex_type = KEX_DH_GEX_SHA512; |
| 300 |
} else |
304 |
} else |
| 301 |
fatal("bad kex alg %s", k->name); |
305 |
fatal("bad kex alg %s", k->name); |
| 302 |
} |
306 |
} |
|
Lines 405-428
kex_choose_conf(Kex *kex)
Link Here
|
| 405 |
} |
409 |
} |
| 406 |
|
410 |
|
| 407 |
static u_char * |
411 |
static u_char * |
| 408 |
derive_key(Kex *kex, int id, int need, u_char *hash, BIGNUM *shared_secret) |
412 |
derive_key(Kex *kex, int id, int need, u_char *hash, u_int hashlen, |
|
|
413 |
BIGNUM *shared_secret) |
| 409 |
{ |
414 |
{ |
| 410 |
Buffer b; |
415 |
Buffer b; |
| 411 |
const EVP_MD *evp_md = EVP_sha1(); |
416 |
const EVP_MD *evp_md; |
| 412 |
EVP_MD_CTX md; |
417 |
EVP_MD_CTX md; |
| 413 |
char c = id; |
418 |
char c = id; |
| 414 |
int have; |
419 |
int have; |
| 415 |
int mdsz = EVP_MD_size(evp_md); |
420 |
int mdsz; |
| 416 |
u_char *digest = xmalloc(roundup(need, mdsz)); |
421 |
u_char *digest; |
| 417 |
|
422 |
|
| 418 |
buffer_init(&b); |
423 |
buffer_init(&b); |
| 419 |
buffer_put_bignum2(&b, shared_secret); |
424 |
buffer_put_bignum2(&b, shared_secret); |
| 420 |
|
425 |
|
|
|
426 |
switch (kex->kex_type) { |
| 427 |
case KEX_DH_GRP1_SHA1: |
| 428 |
case KEX_DH_GRP14_SHA1: |
| 429 |
case KEX_DH_GEX_SHA1: |
| 430 |
evp_md = EVP_sha1(); |
| 431 |
break; |
| 432 |
case KEX_DH_GEX_SHA512: |
| 433 |
evp_md = evp_ssh_sha512(); |
| 434 |
break; |
| 435 |
default: |
| 436 |
fatal("derive_key: unknown kex_type %d", kex->kex_type); |
| 437 |
} |
| 438 |
|
| 439 |
mdsz = EVP_MD_size(evp_md); |
| 440 |
digest = xmalloc(roundup(need, mdsz)); |
| 441 |
|
| 421 |
/* K1 = HASH(K || H || "A" || session_id) */ |
442 |
/* K1 = HASH(K || H || "A" || session_id) */ |
| 422 |
EVP_DigestInit(&md, evp_md); |
443 |
EVP_DigestInit(&md, evp_md); |
| 423 |
if (!(datafellows & SSH_BUG_DERIVEKEY)) |
444 |
if (!(datafellows & SSH_BUG_DERIVEKEY)) |
| 424 |
EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b)); |
445 |
EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b)); |
| 425 |
EVP_DigestUpdate(&md, hash, mdsz); |
446 |
EVP_DigestUpdate(&md, hash, hashlen); |
| 426 |
EVP_DigestUpdate(&md, &c, 1); |
447 |
EVP_DigestUpdate(&md, &c, 1); |
| 427 |
EVP_DigestUpdate(&md, kex->session_id, kex->session_id_len); |
448 |
EVP_DigestUpdate(&md, kex->session_id, kex->session_id_len); |
| 428 |
EVP_DigestFinal(&md, digest, NULL); |
449 |
EVP_DigestFinal(&md, digest, NULL); |
|
Lines 432-438
derive_key(Kex *kex, int id, int need, u
Link Here
|
| 432 |
* Kn = HASH(K || H || K1 || K2 || ... || Kn-1) |
453 |
* Kn = HASH(K || H || K1 || K2 || ... || Kn-1) |
| 433 |
* Key = K1 || K2 || ... || Kn |
454 |
* Key = K1 || K2 || ... || Kn |
| 434 |
*/ |
455 |
*/ |
|
|
456 |
#ifdef DEBUG_KEX |
| 457 |
fprintf(stderr, "expand key: mdsz %d need %d\n", mdsz, need); |
| 458 |
#endif |
| 435 |
for (have = mdsz; need > have; have += mdsz) { |
459 |
for (have = mdsz; need > have; have += mdsz) { |
|
|
460 |
#ifdef DEBUG_KEX |
| 461 |
fprintf(stderr, "expand key: have %d\n", have); |
| 462 |
#endif |
| 436 |
EVP_DigestInit(&md, evp_md); |
463 |
EVP_DigestInit(&md, evp_md); |
| 437 |
if (!(datafellows & SSH_BUG_DERIVEKEY)) |
464 |
if (!(datafellows & SSH_BUG_DERIVEKEY)) |
| 438 |
EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b)); |
465 |
EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b)); |
|
Lines 452-464
Newkeys *current_keys[MODE_MAX];
Link Here
|
| 452 |
|
479 |
|
| 453 |
#define NKEYS 6 |
480 |
#define NKEYS 6 |
| 454 |
void |
481 |
void |
| 455 |
kex_derive_keys(Kex *kex, u_char *hash, BIGNUM *shared_secret) |
482 |
kex_derive_keys(Kex *kex, u_char *hash, u_int hashlen, BIGNUM *shared_secret) |
| 456 |
{ |
483 |
{ |
| 457 |
u_char *keys[NKEYS]; |
484 |
u_char *keys[NKEYS]; |
| 458 |
int i, mode, ctos; |
485 |
int i, mode, ctos; |
| 459 |
|
486 |
|
| 460 |
for (i = 0; i < NKEYS; i++) |
487 |
for (i = 0; i < NKEYS; i++) { |
| 461 |
keys[i] = derive_key(kex, 'A'+i, kex->we_need, hash, shared_secret); |
488 |
keys[i] = derive_key(kex, 'A'+i, kex->we_need, hash, hashlen, |
|
|
489 |
shared_secret); |
| 490 |
} |
| 462 |
|
491 |
|
| 463 |
debug2("kex_derive_keys"); |
492 |
debug2("kex_derive_keys"); |
| 464 |
for (mode = 0; mode < MODE_MAX; mode++) { |
493 |
for (mode = 0; mode < MODE_MAX; mode++) { |