diff options
Diffstat (limited to 'common-kex.c')
| -rw-r--r-- | common-kex.c | 66 |
1 files changed, 30 insertions, 36 deletions
diff --git a/common-kex.c b/common-kex.c index e241101..48569fe 100644 --- a/common-kex.c +++ b/common-kex.c @@ -87,6 +87,7 @@ static void read_kex_algos(); /* helper function for gen_new_keys */ static void hashkeys(unsigned char *out, int outlen, const hash_state * hs, unsigned const char X); +static void finish_kexhashbuf(void); /* Send our list of algorithms we can use */ @@ -258,7 +259,7 @@ static void hashkeys(unsigned char *out, int outlen, memcpy(&hs2, hs, sizeof(hash_state)); sha1_process(&hs2, &X, 1); - sha1_process(&hs2, ses.session_id, SHA1_HASH_SIZE); + sha1_process(&hs2, ses.session_id->data, ses.session_id->len); sha1_done(&hs2, out); for (offset = SHA1_HASH_SIZE; offset < outlen; @@ -301,8 +302,10 @@ void gen_new_keys() { sha1_process_mp(&hs, ses.dh_K); mp_clear(ses.dh_K); m_free(ses.dh_K); - sha1_process(&hs, ses.hash, SHA1_HASH_SIZE); - m_burn(ses.hash, SHA1_HASH_SIZE); + sha1_process(&hs, ses.hash->data, ses.hash->len); + buf_burn(ses.hash); + buf_free(ses.hash); + ses.hash = NULL; if (IS_DROPBEAR_CLIENT) { trans_IV = C2S_IV; @@ -596,8 +599,6 @@ void kexdh_comb_key(struct kex_dh_param *param, mp_int *dh_pub_them, mp_int dh_p; mp_int *dh_e = NULL, *dh_f = NULL; - hash_state hs; - /* read the prime and generator*/ m_mp_init(&dh_p); load_dh_p(&dh_p); @@ -639,25 +640,7 @@ void kexdh_comb_key(struct kex_dh_param *param, mp_int *dh_pub_them, buf_putmpint(ses.kexhashbuf, ses.dh_K); /* calculate the hash H to sign */ - sha1_init(&hs); - buf_setpos(ses.kexhashbuf, 0); - sha1_process(&hs, buf_getptr(ses.kexhashbuf, ses.kexhashbuf->len), - ses.kexhashbuf->len); - - ses.hash = m_malloc(SHA1_HASH_SIZE); - } - sha1_done(&hs, ses.hash); - - buf_burn(ses.kexhashbuf); - buf_free(ses.kexhashbuf); - ses.kexhashbuf = NULL; - - /* first time around, we set the session_id to H */ - if (ses.session_id == NULL) { - /* create the session_id, this never needs freeing */ - ses.session_id = (unsigned char*)m_malloc(SHA1_HASH_SIZE); - memcpy(ses.session_id, ses.hash, SHA1_HASH_SIZE); - } + finish_kexhashbuf(); } #ifdef DROPBEAR_ECDH @@ -685,25 +668,25 @@ void kexecdh_comb_key(struct kex_ecdh_param *param, buffer *pub_them, // XXX load Q_them Q_them = buf_get_ecc_pubkey(pub_them, algo_kex->ecc_curve); - ses.dh_K = dropbear_ecc_shared_secret(Q_them, param->key); + ses.dh_K = dropbear_ecc_shared_secret(Q_them, ¶m->key); /* From here on, the code needs to work with the _same_ vars on each side, * not vice-versaing for client/server */ if (IS_DROPBEAR_CLIENT) { - Q_C = param->key; + Q_C = ¶m->key; Q_S = Q_them; } else { Q_C = Q_them; - Q_S = param->key; + Q_S = ¶m->key; } /* Create the remainder of the hash buffer, to generate the exchange hash */ /* K_S, the host key */ buf_put_pub_key(ses.kexhashbuf, hostkey, ses.newkeys->algo_hostkey); /* Q_C, client's ephemeral public key octet string */ - buf_put_ecc_pubkey_string(Q_C); + buf_put_ecc_pubkey_string(ses.kexhashbuf, Q_C); /* Q_S, server's ephemeral public key octet string */ - buf_put_ecc_pubkey_string(Q_S); + buf_put_ecc_pubkey_string(ses.kexhashbuf, Q_S); /* K, the shared secret */ buf_putmpint(ses.kexhashbuf, ses.dh_K); @@ -712,10 +695,23 @@ void kexecdh_comb_key(struct kex_ecdh_param *param, buffer *pub_them, buf_setpos(ses.kexhashbuf, 0); algo_kex->hashdesc->process(&hs, buf_getptr(ses.kexhashbuf, ses.kexhashbuf->len), ses.kexhashbuf->len); - if (!ses.hash) { - ses.hash = m_malloc(algo_kex->hashdesc->hashsize); - } - algo_kex->hashdesc->done(&hs, ses.hash); + + /* calculate the hash H to sign */ + finish_kexhashbuf(); +} +#endif + +static void finish_kexhashbuf(void) { + hash_state hs; + const struct ltc_hash_descriptor *hashdesc = ses.newkeys->algo_kex->hashdesc; + + hashdesc->init(&hs); + buf_setpos(ses.kexhashbuf, 0); + hashdesc->process(&hs, buf_getptr(ses.kexhashbuf, ses.kexhashbuf->len), + ses.kexhashbuf->len); + ses.hash = buf_new(hashdesc->hashsize); + hashdesc->done(&hs, buf_getwriteptr(ses.hash, hashdesc->hashsize)); + buf_setlen(ses.hash, hashdesc->hashsize); buf_burn(ses.kexhashbuf); buf_free(ses.kexhashbuf); @@ -724,12 +720,10 @@ void kexecdh_comb_key(struct kex_ecdh_param *param, buffer *pub_them, /* first time around, we set the session_id to H */ if (ses.session_id == NULL) { /* create the session_id, this never needs freeing */ - ses.session_id = m_malloc(algo_kex->hashdesc->hashsize); - memcpy(ses.session_id, ses.hash, algo_kex->hashdesc->hashsize); + ses.session_id = buf_newcopy(ses.hash); } } -#endif /* read the other side's algo list. buf_match_algo is a callback to match * algos for the client or server. */ |