svn commit: r301223 - head/sys/dev/cesa

[Zbigniew Bodek]

Author: zbb
Date: Thu Jun  2 18:37:50 2016
New Revision: 301223
URL: https://svnweb.freebsd.org/changeset/base/301223

Log:
  Truncate HMAC output only if requested by the client
  
  The output of HMAC was previously truncated to 12 bytes. This was only
  correct in case of one particular crypto client - the new version of IPSEC.
  Fix by taking into account the cri_mlen field in cryptoini session request
  filled in by the client.
  
  Submitted by:	Michal Stanek <mst at semihalf.com>
  Obtained from:	Semihalf
  Sponsored by:	Stormshield
  Differential revision:	https://reviews.freebsd.org/D6218

Modified:
  head/sys/dev/cesa/cesa.c
  head/sys/dev/cesa/cesa.h

Modified: head/sys/dev/cesa/cesa.c
==============================================================================
--- head/sys/dev/cesa/cesa.c	Thu Jun  2 18:35:35 2016	(r301222)
+++ head/sys/dev/cesa/cesa.c	Thu Jun  2 18:37:50 2016	(r301223)
@@ -1451,24 +1451,32 @@ cesa_newsession(device_t dev, uint32_t *
 	if (!error && mac) {
 		switch (mac->cri_alg) {
 		case CRYPTO_MD5:
-			cs->cs_config |= CESA_CSHD_MD5;
 			cs->cs_mblen = 1;
-			cs->cs_hlen = MD5_HASH_LEN;
+			cs->cs_hlen = (mac->cri_mlen == 0) ? MD5_HASH_LEN :
+			    mac->cri_mlen;
+			cs->cs_config |= CESA_CSHD_MD5;
 			break;
 		case CRYPTO_MD5_HMAC:
-			cs->cs_config |= CESA_CSHD_MD5_HMAC;
 			cs->cs_mblen = MD5_HMAC_BLOCK_LEN;
-			cs->cs_hlen = CESA_HMAC_HASH_LENGTH;
+			cs->cs_hlen = (mac->cri_mlen == 0) ? MD5_HASH_LEN :
+			    mac->cri_mlen;
+			cs->cs_config |= CESA_CSHD_MD5_HMAC;
+			if (cs->cs_hlen == CESA_HMAC_TRUNC_LEN)
+				cs->cs_config |= CESA_CSHD_96_BIT_HMAC;
 			break;
 		case CRYPTO_SHA1:
-			cs->cs_config |= CESA_CSHD_SHA1;
 			cs->cs_mblen = 1;
-			cs->cs_hlen = SHA1_HASH_LEN;
+			cs->cs_hlen = (mac->cri_mlen == 0) ? SHA1_HASH_LEN :
+			    mac->cri_mlen;
+			cs->cs_config |= CESA_CSHD_SHA1;
 			break;
 		case CRYPTO_SHA1_HMAC:
-			cs->cs_config |= CESA_CSHD_SHA1_HMAC;
 			cs->cs_mblen = SHA1_HMAC_BLOCK_LEN;
-			cs->cs_hlen = CESA_HMAC_HASH_LENGTH;
+			cs->cs_hlen = (mac->cri_mlen == 0) ? SHA1_HASH_LEN :
+			    mac->cri_mlen;
+			cs->cs_config |= CESA_CSHD_SHA1_HMAC;
+			if (cs->cs_hlen == CESA_HMAC_TRUNC_LEN)
+				cs->cs_config |= CESA_CSHD_96_BIT_HMAC;
 			break;
 		default:
 			error = EINVAL;

Modified: head/sys/dev/cesa/cesa.h
==============================================================================
--- head/sys/dev/cesa/cesa.h	Thu Jun  2 18:35:35 2016	(r301222)
+++ head/sys/dev/cesa/cesa.h	Thu Jun  2 18:37:50 2016	(r301223)
@@ -68,7 +68,7 @@
 #define CESA_TDMA_DESCRIPTORS		(CESA_TDMA_DESC_PER_REQ * CESA_REQUESTS)
 
 /* Useful constants */
-#define CESA_HMAC_HASH_LENGTH		12
+#define CESA_HMAC_TRUNC_LEN		12
 #define CESA_MAX_FRAGMENTS		64
 #define CESA_SRAM_SIZE			2048
 
@@ -293,8 +293,10 @@ struct cesa_chain_info {
 
 #define CESA_CSHD_MD5			(4 << 4)
 #define CESA_CSHD_SHA1			(5 << 4)
-#define CESA_CSHD_MD5_HMAC		((6 << 4) | (1 << 7))
-#define CESA_CSHD_SHA1_HMAC		((7 << 4) | (1 << 7))
+#define CESA_CSHD_MD5_HMAC		(6 << 4)
+#define CESA_CSHD_SHA1_HMAC		(7 << 4)
+
+#define CESA_CSHD_96_BIT_HMAC		(1 << 7)
 
 #define CESA_CSHD_DES			(1 << 8)
 #define CESA_CSHD_3DES			(2 << 8)