From David Dahlberg:

As for now, Wireshark supports only 96-bit (or 0-bit for NULL authentication)
integrity control values (ICVs) for IPsec ESP. While the autentication field is
of variable length, this may lead to situations where the whole packet is not
parsable.

To solve this, I added generic classes (not checked) for 128, 192 and 256 bit
ICVs to the ESP dissector. I also split the HMAC-SHA-256 autentication
algorithm to HMAC-SHA-256-128 (128 bit as defined in RFC 4868) and
HMAC-SHA-256-96 (from the very first draft, nevertheless unpatched Linux and
BSDs do it this way).

svn path=/trunk/; revision=29121

1 files changed, 58 insertions, 12 deletions

diff --git a/epan/dissectors/packet-ipsec.c b/epan/dissectors/packet-ipsec.c
index 200be05112..cbbda333d0 100644
--- a/epan/dissectors/packet-ipsec.c
+++ b/epan/dissectors/packet-ipsec.c
@@ -57,6 +57,16 @@ AES-XCBC-MAC-96 [RFC3566] : Not available because no implementation found.
 - Add ESP Authentication checking for the following Authentication Algorithm :
 HMAC-SHA256 : any keylen
 HMAC-RIPEMD160-96 [RFC2857] : any keylen
+
+- Added/Modified Authentication checking (David Dahlberg <dahlberg@fgan.de>):
+CHG: HMAC-SHA256 is now HMAC-SHA-256-96 [draft-ietf-ipsec-ciph-sha-256-00]
+     -> It is implemented this way in USAGI/KAME (Linux/BSD).
+ADD: HMAC-SHA-256-128 [RFC4868]
+     ICV length of HMAC-SHA-256 was changed in draft-ietf-ipsec-ciph-sha-256-01 
+     to 128 bit. This is "SHOULD" be the standard now!
+ADD: Additional generic (non-checked) ICV length of 128, 192 and 256.
+     This follows RFC 4868 for the SHA-256+ family.
+
 */
 
 #ifdef HAVE_CONFIG_H
@@ -125,11 +135,15 @@ static dissector_table_t ip_dissector_table;
 /* Authentication algorithms defined in RFC 4305 */
 #define IPSEC_AUTH_NULL 0
 #define IPSEC_AUTH_HMAC_SHA1_96 1
-#define IPSEC_AUTH_HMAC_SHA256 2
-#define IPSEC_AUTH_HMAC_MD5_96 3
-#define IPSEC_AUTH_HMAC_RIPEMD160_96 4
-#define IPSEC_AUTH_ANY_12BYTES 5
+#define IPSEC_AUTH_HMAC_SHA256_96 2
+#define IPSEC_AUTH_HMAC_SHA256_128 3
+#define IPSEC_AUTH_HMAC_MD5_96 4
+#define IPSEC_AUTH_HMAC_RIPEMD160_96 5
 /* define IPSEC_AUTH_AES_XCBC_MAC_96 6 */
+#define IPSEC_AUTH_ANY_96BIT 7
+#define IPSEC_AUTH_ANY_128BIT 8
+#define IPSEC_AUTH_ANY_192BIT 9
+#define IPSEC_AUTH_ANY_256BIT 10
 #endif
 
 /* well-known algorithm number (in CPI), from RFC2409 */
@@ -1746,12 +1760,18 @@ dissect_esp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 		    break;
 		  }
 
-		case IPSEC_AUTH_HMAC_SHA256:
+		case IPSEC_AUTH_HMAC_SHA256_96:
 		  {
 		    esp_auth_len = 12;
 		    break;
 		  }
 
+		case IPSEC_AUTH_HMAC_SHA256_128:
+		  {
+		    esp_auth_len = 16;
+		    break;
+		  }
+
 		case IPSEC_AUTH_NULL:
 		  {
 		    esp_auth_len = 0;
@@ -1778,7 +1798,25 @@ dissect_esp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 		    break;
 		  }
 
-		case IPSEC_AUTH_ANY_12BYTES:
+		case IPSEC_AUTH_ANY_256BIT:
+		  {
+		    esp_auth_len = 32;
+		    break;
+		  }
+
+		case IPSEC_AUTH_ANY_192BIT:
+		  {
+		    esp_auth_len = 24;
+		    break;
+		  }
+
+		case IPSEC_AUTH_ANY_128BIT:
+		  {
+		    esp_auth_len = 16;
+		    break;
+		  }
+
+		case IPSEC_AUTH_ANY_96BIT:
 		default:
 		  {
 		    esp_auth_len = 12;
@@ -1829,7 +1867,8 @@ dissect_esp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 			}
 		      */
 
-		    case IPSEC_AUTH_HMAC_SHA256:
+		    case IPSEC_AUTH_HMAC_SHA256_96:
+		    case IPSEC_AUTH_HMAC_SHA256_128:
 		      {
 			auth_algo_libgcrypt = GCRY_MD_SHA256;
 			authentication_check_using_hmac_libgcrypt = TRUE;
@@ -1870,7 +1909,10 @@ dissect_esp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 			break;
 		      }
 
-		    case IPSEC_AUTH_ANY_12BYTES:
+		    case IPSEC_AUTH_ANY_96BIT:
+		    case IPSEC_AUTH_ANY_128BIT:
+		    case IPSEC_AUTH_ANY_192BIT:
+		    case IPSEC_AUTH_ANY_256BIT:
 		    default:
 		      {
 			authentication_ok = FALSE;
@@ -2690,12 +2732,16 @@ proto_register_ipsec(void)
   static enum_val_t esp_authentication_algo[] = {
 
     {"null", "NULL", IPSEC_AUTH_NULL},
-    {"hmacsha196", "HMAC-SHA1-96 [RFC2404]", IPSEC_AUTH_HMAC_SHA1_96},
-    {"hmacsha256", "HMAC-SHA256", IPSEC_AUTH_HMAC_SHA256},
+    {"hmacsha196", "HMAC-SHA-1-96 [RFC2404]", IPSEC_AUTH_HMAC_SHA1_96},
+    {"hmacsha25696", "HMAC-SHA-256-96 [draft-ietf-ipsec-ciph-sha-256-00]", IPSEC_AUTH_HMAC_SHA256_96},
+    {"hmacsha256128", "HMAC-SHA-256-128 [RFC4868]", IPSEC_AUTH_HMAC_SHA256_128},
     {"hmacmd596", "HMAC-MD5-96 [RFC2403]", IPSEC_AUTH_HMAC_MD5_96},
-    {"hmacripemd160", "HMAC-RIPEMD", IPSEC_AUTH_HMAC_RIPEMD160_96},
+    {"hmacripemd160", "MAC-RIPEMD-160-96 [RFC2857]", IPSEC_AUTH_HMAC_RIPEMD160_96},
     /*    {"aesxcbcmac96", "AES-XCBC-MAC-96 [RFC3566]", IPSEC_AUTH_AES_XCBC_MAC_96}, */
-    {"any12bytes", "ANY 12-bytes of Authentication [No Checking]", IPSEC_AUTH_ANY_12BYTES},
+    {"any96bit",   "ANY 96 bit authentication [no checking]", IPSEC_AUTH_ANY_96BIT},
+    {"any128bit", "ANY 128 bit authentication [no checking]", IPSEC_AUTH_ANY_128BIT},
+    {"any192bit", "ANY 192 bit authentication [no checking]", IPSEC_AUTH_ANY_192BIT},
+    {"any256bit", "ANY 256 bit authentication [no checking]", IPSEC_AUTH_ANY_256BIT},
     {NULL,NULL,0}
   };
 #endif