From cf585ba1dee7a7e1f2fbc90d2251d99b7da66a7e Mon Sep 17 00:00:00 2001 From: Matt Johnston Date: Thu, 5 May 2005 03:58:21 +0000 Subject: - refactored random mp_int generation and byte->mp_int code - added RSA blinding --HG-- extra : convert_revision : 5d5b4657a24a1c8f53c6fc45d5ec29ddb85fb45a --- common-kex.c | 24 ++++-------------------- 1 file changed, 4 insertions(+), 20 deletions(-) (limited to 'common-kex.c') diff --git a/common-kex.c b/common-kex.c index a2336c5..8a8aa93 100644 --- a/common-kex.c +++ b/common-kex.c @@ -469,18 +469,13 @@ void gen_kexdh_vals(mp_int *dh_pub, mp_int *dh_priv) { DEF_MP_INT(dh_p); DEF_MP_INT(dh_q); DEF_MP_INT(dh_g); - unsigned char randbuf[DH_P_LEN]; - int dh_q_len; TRACE(("enter send_msg_kexdh_reply")) m_mp_init_multi(&dh_g, &dh_p, &dh_q, NULL); /* read the prime and generator*/ - if (mp_read_unsigned_bin(&dh_p, (unsigned char*)dh_p_val, DH_P_LEN) - != MP_OKAY) { - dropbear_exit("Diffie-Hellman error"); - } + bytes_to_mp(&dh_p, (unsigned char*)dh_p_val, DH_P_LEN); if (mp_set_int(&dh_g, DH_G_VAL) != MP_OKAY) { dropbear_exit("Diffie-Hellman error"); @@ -495,16 +490,8 @@ void gen_kexdh_vals(mp_int *dh_pub, mp_int *dh_priv) { dropbear_exit("Diffie-Hellman error"); } - dh_q_len = mp_unsigned_bin_size(&dh_q); - - /* calculate our random value dh_y */ - do { - assert((unsigned int)dh_q_len <= sizeof(randbuf)); - genrandom(randbuf, dh_q_len); - if (mp_read_unsigned_bin(dh_priv, randbuf, dh_q_len) != MP_OKAY) { - dropbear_exit("Diffie-Hellman error"); - } - } while (mp_cmp(dh_priv, &dh_q) == MP_GT || mp_cmp_d(dh_priv, 0) != MP_GT); + /* Generate a private portion 0 < dh_priv < dh_q */ + gen_random_mpint(&dh_q, dh_priv); /* f = g^y mod p */ if (mp_exptmod(&dh_g, dh_priv, &dh_p, dh_pub) != MP_OKAY) { @@ -526,10 +513,7 @@ void kexdh_comb_key(mp_int *dh_pub_us, mp_int *dh_priv, mp_int *dh_pub_them, /* read the prime and generator*/ mp_init(&dh_p); - if (mp_read_unsigned_bin(&dh_p, (unsigned char*)dh_p_val, DH_P_LEN) - != MP_OKAY) { - dropbear_exit("Diffie-Hellman error"); - } + bytes_to_mp(&dh_p, dh_p_val, DH_P_LEN); /* Check that dh_pub_them (dh_e or dh_f) is in the range [1, p-1] */ if (mp_cmp(dh_pub_them, &dh_p) != MP_LT -- cgit v1.2.3