check p and q lengths

--HG--
branch : fuzz
This commit is contained in:
Matt Johnston 2017-06-16 22:35:18 +08:00
parent 88ce30beb6
commit e3246ceb7e
2 changed files with 13 additions and 3 deletions

13
dss.c
View File

@ -61,8 +61,15 @@ int buf_get_dss_pub_key(buffer* buf, dropbear_dss_key *key) {
goto out;
}
if (mp_count_bits(key->p) < MIN_DSS_KEYLEN) {
dropbear_log(LOG_WARNING, "DSS key too short");
if (mp_count_bits(key->p) < DSS_P_BITS) {
dropbear_log(LOG_WARNING, "Bad DSS p");
TRACE(("leave buf_get_dss_pub_key: short key"))
ret = DROPBEAR_FAILURE;
goto out;
}
if (mp_count_bits(key->q) < DSS_Q_BITS) {
dropbear_log(LOG_WARNING, "Bad DSS q");
TRACE(("leave buf_get_dss_pub_key: short key"))
ret = DROPBEAR_FAILURE;
goto out;
@ -94,7 +101,7 @@ int buf_get_dss_priv_key(buffer* buf, dropbear_dss_key *key) {
m_mp_alloc_init_multi(&key->x, NULL);
ret = buf_getmpint(buf, key->x);
if (ret == DROPBEAR_FAILURE) {
m_mp_free_multi(&key->x);
m_mp_free_multi(&key->x, NULL);
}
return ret;

3
dss.h
View File

@ -41,6 +41,9 @@ typedef struct {
} dropbear_dss_key;
#define DSS_P_BITS 1024
#define DSS_Q_BITS 160
void buf_put_dss_sign(buffer* buf, dropbear_dss_key *key, buffer *data_buf);
#if DROPBEAR_SIGNKEY_VERIFY
int buf_dss_verify(buffer* buf, dropbear_dss_key *key, buffer *data_buf);