svn commit: r362627 - head/sys/dev/glxsb

[John Baldwin]

Author: jhb
Date: Thu Jun 25 20:21:34 2020
New Revision: 362627
URL: https://svnweb.freebsd.org/changeset/base/362627

Log:
  Explicitly zero hash results and context in glxsb_authcompute().
  
  Reviewed by:	delphij
  Sponsored by:	Chelsio Communications
  Differential Revision:	https://reviews.freebsd.org/D25438

Modified:
  head/sys/dev/glxsb/glxsb_hash.c

Modified: head/sys/dev/glxsb/glxsb_hash.c
==============================================================================
--- head/sys/dev/glxsb/glxsb_hash.c	Thu Jun 25 20:20:22 2020	(r362626)
+++ head/sys/dev/glxsb/glxsb_hash.c	Thu Jun 25 20:21:34 2020	(r362627)
@@ -65,7 +65,7 @@ glxsb_hash_key_setup(struct glxsb_session *ses, const 
 static int
 glxsb_authcompute(struct glxsb_session *ses, struct cryptop *crp)
 {
-	u_char hash[HASH_MAX_LEN], hash2[HASH_MAX_LEN];
+	u_char hash[HASH_MAX_LEN];
 	struct auth_hash *axf;
 	union authctx ctx;
 	int error;
@@ -86,17 +86,22 @@ glxsb_authcompute(struct glxsb_session *ses, struct cr
 	bcopy(ses->ses_octx, &ctx, axf->ctxsize);
 	axf->Update(&ctx, hash, axf->hashsize);
 	axf->Final(hash, &ctx);
+	explicit_bzero(&ctx, sizeof(ctx));
 
 	/* Verify or inject the authentication data */
 	if (crp->crp_op & CRYPTO_OP_VERIFY_DIGEST) {
+		u_char hash2[HASH_MAX_LEN];
+
 		crypto_copydata(crp, crp->crp_digest_start, ses->ses_mlen,
 		    hash2);
 		if (timingsafe_bcmp(hash, hash2, ses->ses_mlen) != 0)
-			return (EBADMSG);
+			error = EBADMSG;
+		explicit_bzero(hash2, sizeof(hash2));
 	} else
 		crypto_copyback(crp, crp->crp_digest_start, ses->ses_mlen,
 		    hash);
-	return (0);
+	explicit_bzero(hash, sizeof(hash));
+	return (error);
 }
 
 int