diff options
Diffstat (limited to 'ecc.c')
| -rw-r--r-- | ecc.c | 15 |
1 files changed, 12 insertions, 3 deletions
@@ -142,14 +142,18 @@ ecc_key * buf_get_ecc_raw_pubkey(buffer *buf, const struct dropbear_ecc_curve *c ecc_key *key = NULL; int ret = DROPBEAR_FAILURE; const unsigned int size = curve->dp->size; + unsigned char first; + + TRACE(("enter buf_get_ecc_raw_pubkey")) + buf_setpos(buf, 0); - unsigned int len = buf->len; - unsigned char first = buf_getbyte(buf); + first = buf_getbyte(buf); if (first == 2 || first == 3) { dropbear_log(LOG_WARNING, "Dropbear doesn't support ECC point compression"); return NULL; } - if (first != 4 || len != 1+2*size) { + if (first != 4 || buf->len != 1+2*size) { + TRACE(("leave, wrong size")) return NULL; } @@ -157,11 +161,13 @@ ecc_key * buf_get_ecc_raw_pubkey(buffer *buf, const struct dropbear_ecc_curve *c key->dp = curve->dp; if (mp_read_unsigned_bin(key->pubkey.x, buf_getptr(buf, size), size) != MP_OKAY) { + TRACE(("failed to read x")) goto out; } buf_incrpos(buf, size); if (mp_read_unsigned_bin(key->pubkey.y, buf_getptr(buf, size), size) != MP_OKAY) { + TRACE(("failed to read y")) goto out; } buf_incrpos(buf, size); @@ -169,14 +175,17 @@ ecc_key * buf_get_ecc_raw_pubkey(buffer *buf, const struct dropbear_ecc_curve *c mp_set(key->pubkey.z, 1); if (ecc_is_point(key) != CRYPT_OK) { + TRACE(("failed, not a point")) goto out; } // SEC1 3.2.3.1 Check that Q != 0 if (mp_cmp_d(key->pubkey.x, 0) == LTC_MP_EQ) { + TRACE(("failed, x == 0")) goto out; } if (mp_cmp_d(key->pubkey.y, 0) == LTC_MP_EQ) { + TRACE(("failed, y == 0")) goto out; } |