Author: jhb Date: Wed Jun 3 22:15:11 2020 New Revision: 361774 URL: https://svnweb.freebsd.org/changeset/base/361774
Log: Explicitly zero on-stack IVs, tags, and HMAC keys. Reviewed by: delphij Sponsored by: Netflix Differential Revision: https://reviews.freebsd.org/D25057 Modified: head/sys/crypto/aesni/aesni.c Modified: head/sys/crypto/aesni/aesni.c ============================================================================== --- head/sys/crypto/aesni/aesni.c Wed Jun 3 22:11:05 2020 (r361773) +++ head/sys/crypto/aesni/aesni.c Wed Jun 3 22:15:11 2020 (r361774) @@ -815,6 +815,8 @@ out: explicit_bzero(outbuf, crp->crp_payload_length); free(outbuf, M_AESNI); } + explicit_bzero(iv, sizeof(iv)); + explicit_bzero(tag, sizeof(tag)); return (error); } @@ -826,9 +828,7 @@ aesni_cipher_mac(struct aesni_session *ses, struct cry struct SHA256Context sha2 __aligned(16); struct sha1_ctxt sha1 __aligned(16); } sctx; - uint8_t hmac_key[SHA1_BLOCK_LEN] __aligned(16); uint32_t res[SHA2_256_HASH_LEN / sizeof(uint32_t)]; - uint32_t res2[SHA2_256_HASH_LEN / sizeof(uint32_t)]; const uint8_t *key; int i, keylen; @@ -839,6 +839,8 @@ aesni_cipher_mac(struct aesni_session *ses, struct cry keylen = csp->csp_auth_klen; if (ses->hmac) { + uint8_t hmac_key[SHA1_BLOCK_LEN] __aligned(16); + /* Inner hash: (K ^ IPAD) || data */ ses->hash_init(&sctx); for (i = 0; i < keylen; i++) @@ -869,6 +871,7 @@ aesni_cipher_mac(struct aesni_session *ses, struct cry ses->hash_update(&sctx, hmac_key, sizeof(hmac_key)); ses->hash_update(&sctx, res, ses->hash_len); ses->hash_finalize(res, &sctx); + explicit_bzero(hmac_key, sizeof(hmac_key)); } else { ses->hash_init(&sctx); @@ -889,10 +892,14 @@ aesni_cipher_mac(struct aesni_session *ses, struct cry } if (crp->crp_op & CRYPTO_OP_VERIFY_DIGEST) { + uint32_t res2[SHA2_256_HASH_LEN / sizeof(uint32_t)]; + crypto_copydata(crp, crp->crp_digest_start, ses->mlen, res2); if (timingsafe_bcmp(res, res2, ses->mlen) != 0) return (EBADMSG); + explicit_bzero(res2, sizeof(res2)); } else crypto_copyback(crp, crp->crp_digest_start, ses->mlen, res); + explicit_bzero(res, sizeof(res)); return (0); } _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "[email protected]"
