diff options
Diffstat (limited to 'rsa.c')
| -rw-r--r-- | rsa.c | 21 |
1 files changed, 16 insertions, 5 deletions
@@ -300,18 +300,29 @@ void buf_put_rsa_sign(buffer* buf, rsa_key *key, const unsigned char* data, /* rsa_tmp1 is em */ /* em' = em * r^e mod n */ - mp_exptmod(&rsa_tmp2, key->e, key->n, &rsa_s); /* rsa_s used as a temp var*/ - mp_invmod(&rsa_tmp2, key->n, &rsa_tmp3); - mp_mulmod(&rsa_tmp1, &rsa_s, key->n, &rsa_tmp2); + /* rsa_s used as a temp var*/ + if (mp_exptmod(&rsa_tmp2, key->e, key->n, &rsa_s) != MP_OKAY) { + dropbear_exit("rsa error"); + } + if (mp_invmod(&rsa_tmp2, key->n, &rsa_tmp3) != MP_OKAY) { + dropbear_exit("rsa error"); + } + if (mp_mulmod(&rsa_tmp1, &rsa_s, key->n, &rsa_tmp2) != MP_OKAY) { + dropbear_exit("rsa error"); + } /* rsa_tmp2 is em' */ /* s' = (em')^d mod n */ - mp_exptmod(&rsa_tmp2, key->d, key->n, &rsa_tmp1); + if (mp_exptmod(&rsa_tmp2, key->d, key->n, &rsa_tmp1) != MP_OKAY) { + dropbear_exit("rsa error"); + } /* rsa_tmp1 is s' */ /* rsa_tmp3 is r^(-1) mod n */ /* s = (s')r^(-1) mod n */ - mp_mulmod(&rsa_tmp1, &rsa_tmp3, key->n, &rsa_s); + if (mp_mulmod(&rsa_tmp1, &rsa_tmp3, key->n, &rsa_s) != MP_OKAY) { + dropbear_exit("rsa error"); + } #else |