svn commit: r362123 - head/sys/crypto/aesni

[John Baldwin]

Author: jhb
Date: Fri Jun 12 21:33:02 2020
New Revision: 362123
URL: https://svnweb.freebsd.org/changeset/base/362123

Log:
  Fix AES-CCM requests with an AAD size smaller than a single block.
  
  The amount to copy for the first block is the minimum of the size of
  the AAD region or the remaining space in the first block.
  
  Reported by:	cryptocheck -z
  MFC after:	2 weeks
  Sponsored by:	Netflix
  Differential Revision:	https://reviews.freebsd.org/D25140

Modified:
  head/sys/crypto/aesni/aesni_ccm.c

Modified: head/sys/crypto/aesni/aesni_ccm.c
==============================================================================
--- head/sys/crypto/aesni/aesni_ccm.c	Fri Jun 12 21:21:18 2020	(r362122)
+++ head/sys/crypto/aesni/aesni_ccm.c	Fri Jun 12 21:33:02 2020	(r362123)
@@ -155,7 +155,7 @@ cbc_mac_start(const unsigned char *auth_data, size_t a
 		 * already partially filled, by auth_amt, so we need
 		 * to handle that.  The last block needs to be zero padded.
 		 */
-		copy_amt = MIN(auth_len - auth_amt,
+		copy_amt = MIN(auth_len,
 		    sizeof(staging_block) - auth_amt);
 		byte_ptr = (uint8_t*)&staging_block;
 		bcopy(auth_ptr, &byte_ptr[auth_amt], copy_amt);