diff options
| author | Matt Caswell <matt@openssl.org> | 2021-11-15 12:14:03 +0000 |
|---|---|---|
| committer | Matt Caswell <matt@openssl.org> | 2021-11-16 13:28:40 +0000 |
| commit | c41df3bd2d35d265103aa033a754dd66a13ec81a (patch) | |
| tree | 5f231336e3b43c2c6c5001c621ac8e4f7177fdae /crypto/ec | |
| parent | 1373090503ecdcc93623218913477113d34883e1 (diff) | |
Don't create an ECX key with short keys
If an ECX key is created and the private key is too short, a fromdata
call would create the key, and then later detect the error and report it
after freeing the key. However freeing the key was calling
OPENSSL_secure_clear_free() and assuming that the private key was of the
correct length. If it was actually too short this will write over memory
that it shouldn't.
Fixes #17017
Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17041)
(cherry picked from commit 50938aec35fd57fb3bec707ead2eee381fcfaf04)
Diffstat (limited to 'crypto/ec')
| -rw-r--r-- | crypto/ec/ecx_backend.c | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/crypto/ec/ecx_backend.c b/crypto/ec/ecx_backend.c index a0144d5a86..2ab7611be9 100644 --- a/crypto/ec/ecx_backend.c +++ b/crypto/ec/ecx_backend.c @@ -70,11 +70,23 @@ int ossl_ecx_key_fromdata(ECX_KEY *ecx, const OSSL_PARAM params[], if (param_pub_key == NULL && param_priv_key == NULL) return 0; - if (param_priv_key != NULL - && !OSSL_PARAM_get_octet_string(param_priv_key, - (void **)&ecx->privkey, ecx->keylen, - &privkeylen)) - return 0; + if (param_priv_key != NULL) { + if (!OSSL_PARAM_get_octet_string(param_priv_key, + (void **)&ecx->privkey, ecx->keylen, + &privkeylen)) + return 0; + if (privkeylen != ecx->keylen) { + /* + * Invalid key length. We will clear what we've received now. We + * can't leave it to ossl_ecx_key_free() because that will call + * OPENSSL_secure_clear_free() and assume the correct key length + */ + OPENSSL_secure_clear_free(ecx->privkey, privkeylen); + ecx->privkey = NULL; + return 0; + } + } + pubkey = ecx->pubkey; if (param_pub_key != NULL @@ -83,8 +95,7 @@ int ossl_ecx_key_fromdata(ECX_KEY *ecx, const OSSL_PARAM params[], sizeof(ecx->pubkey), &pubkeylen)) return 0; - if ((param_pub_key != NULL && pubkeylen != ecx->keylen) - || (param_priv_key != NULL && privkeylen != ecx->keylen)) + if ((param_pub_key != NULL && pubkeylen != ecx->keylen)) return 0; if (param_pub_key == NULL && !ossl_ecx_public_from_private(ecx)) |