aboutsummaryrefslogtreecommitdiffstats
path: root/lib/crypto/c_src
diff options
context:
space:
mode:
authorDoug Hogan <[email protected]>2019-01-03 23:35:17 -0800
committerDoug Hogan <[email protected]>2019-01-08 01:11:58 -0800
commit7040f760cb41639024b114f15e4f6d28a154864c (patch)
tree2d11eb548cd01aa908f5ac4f16e7116a4254da9d /lib/crypto/c_src
parent0eab42611349dace5a596fcbd495bd5e1ddf1d19 (diff)
downloadotp-7040f760cb41639024b114f15e4f6d28a154864c.tar.gz
otp-7040f760cb41639024b114f15e4f6d28a154864c.tar.bz2
otp-7040f760cb41639024b114f15e4f6d28a154864c.zip
Revamp srp_host_secret_nif()
* Add error checking on all OpenSSL calls. * Change dlen to int. * Consolidate all of the freeing of resources into a common path.
Diffstat (limited to 'lib/crypto/c_src')
-rw-r--r--lib/crypto/c_src/srp.c116
1 files changed, 69 insertions, 47 deletions
diff --git a/lib/crypto/c_src/srp.c b/lib/crypto/c_src/srp.c
index e5ef72af08..5a49a1c1b4 100644
--- a/lib/crypto/c_src/srp.c
+++ b/lib/crypto/c_src/srp.c
@@ -224,63 +224,85 @@ ERL_NIF_TERM srp_host_secret_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM ar
<premaster secret> = (A * v^u) ^ b % N
*/
BIGNUM *bn_b = NULL, *bn_verifier = NULL;
- BIGNUM *bn_prime = NULL, *bn_A = NULL, *bn_u = NULL, *bn_base, *bn_result;
- BN_CTX *bn_ctx;
- unsigned char* ptr;
- unsigned dlen;
+ BIGNUM *bn_prime = NULL, *bn_A = NULL, *bn_u = NULL, *bn_base = NULL, *bn_result = NULL;
+ BN_CTX *bn_ctx = NULL;
+ unsigned char *ptr;
+ int dlen;
ERL_NIF_TERM ret;
CHECK_NO_FIPS_MODE();
- if (!get_bn_from_bin(env, argv[0], &bn_verifier)
- || !get_bn_from_bin(env, argv[1], &bn_b)
- || !get_bn_from_bin(env, argv[2], &bn_u)
- || !get_bn_from_bin(env, argv[3], &bn_A)
- || !get_bn_from_bin(env, argv[4], &bn_prime))
- {
- if (bn_verifier) BN_free(bn_verifier);
- if (bn_b) BN_free(bn_b);
- if (bn_u) BN_free(bn_u);
- if (bn_A) BN_free(bn_A);
- if (bn_prime) BN_free(bn_prime);
- return enif_make_badarg(env);
- }
-
- bn_ctx = BN_CTX_new();
- bn_result = BN_new();
+ if (argc != 5)
+ goto bad_arg;
+ if (!get_bn_from_bin(env, argv[0], &bn_verifier))
+ goto bad_arg;
+ if (!get_bn_from_bin(env, argv[1], &bn_b))
+ goto bad_arg;
+ if (!get_bn_from_bin(env, argv[2], &bn_u))
+ goto bad_arg;
+ if (!get_bn_from_bin(env, argv[3], &bn_A))
+ goto bad_arg;
+ if (!get_bn_from_bin(env, argv[4], &bn_prime))
+ goto bad_arg;
- /* check that A % N != 0 */
- BN_nnmod(bn_result, bn_A, bn_prime, bn_ctx);
- if (BN_is_zero(bn_result)) {
- BN_free(bn_b);
- BN_free(bn_verifier);
- BN_free(bn_prime);
- BN_free(bn_A);
- BN_CTX_free(bn_ctx);
+ if ((bn_ctx = BN_CTX_new()) == NULL)
+ goto err;
+ if ((bn_result = BN_new()) == NULL)
+ goto err;
- return atom_error;
- }
+ /* check that A % N != 0 */
+ if (!BN_nnmod(bn_result, bn_A, bn_prime, bn_ctx))
+ goto err;
+ if (BN_is_zero(bn_result))
+ goto err;
/* (A * v^u) */
- bn_base = BN_new();
- BN_mod_exp(bn_base, bn_verifier, bn_u, bn_prime, bn_ctx);
- BN_mod_mul(bn_base, bn_A, bn_base, bn_prime, bn_ctx);
+ if ((bn_base = BN_new()) == NULL)
+ goto err;
+ if (!BN_mod_exp(bn_base, bn_verifier, bn_u, bn_prime, bn_ctx))
+ goto err;
+ if (!BN_mod_mul(bn_base, bn_A, bn_base, bn_prime, bn_ctx))
+ goto err;
/* (A * v^u) ^ b % N */
- BN_mod_exp(bn_result, bn_base, bn_b, bn_prime, bn_ctx);
-
- dlen = BN_num_bytes(bn_result);
- ptr = enif_make_new_binary(env, dlen, &ret);
- BN_bn2bin(bn_result, ptr);
- BN_free(bn_result);
- BN_CTX_free(bn_ctx);
-
- BN_free(bn_u);
- BN_free(bn_base);
- BN_free(bn_verifier);
- BN_free(bn_prime);
- BN_free(bn_A);
- BN_free(bn_b);
+ if (!BN_mod_exp(bn_result, bn_base, bn_b, bn_prime, bn_ctx))
+ goto err;
+
+ if ((dlen = BN_num_bytes(bn_result)) < 0)
+ goto err;
+ if ((ptr = enif_make_new_binary(env, (size_t)dlen, &ret)) == NULL)
+ goto err;
+
+ if (BN_bn2bin(bn_result, ptr) < 0)
+ goto err;
+
+ goto done;
+
+ bad_arg:
+ ret = enif_make_badarg(env);
+ goto done;
+
+ err:
+ ret = atom_error;
+
+ done:
+ if (bn_verifier)
+ BN_free(bn_verifier);
+ if (bn_b)
+ BN_free(bn_b);
+ if (bn_u)
+ BN_free(bn_u);
+ if (bn_A)
+ BN_free(bn_A);
+ if (bn_prime)
+ BN_free(bn_prime);
+ if (bn_ctx)
+ BN_CTX_free(bn_ctx);
+ if (bn_result)
+ BN_free(bn_result);
+ if (bn_base)
+ BN_free(bn_base);
+
return ret;
}