[linux-cifs-client] [PATCH 5/6] [CIFS] add OIDs for KRB5 and MSKRB5 to ASN1 parsing routines

[Jeff Layton]

Also, fix the parser to recognize them and set the secType
accordingly. Make CIFSSMBNegotiate not error out automatically
after parsing the securityBlob.

Thanks to Igor Mammedov for the initial version of this patch.

Signed-off-by: Jeff Layton <jlayton at redhat.com>
---
 fs/cifs/asn1.c    |   35 ++++++++++++++++++++++++-----------
 fs/cifs/cifssmb.c |    3 +--
 2 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/fs/cifs/asn1.c b/fs/cifs/asn1.c
index 2a01f3e..bcda2c6 100644
--- a/fs/cifs/asn1.c
+++ b/fs/cifs/asn1.c
@@ -77,8 +77,12 @@
 
 #define SPNEGO_OID_LEN 7
 #define NTLMSSP_OID_LEN  10
+#define KRB5_OID_LEN  7
+#define MSKRB5_OID_LEN  7
 static unsigned long SPNEGO_OID[7] = { 1, 3, 6, 1, 5, 5, 2 };
 static unsigned long NTLMSSP_OID[10] = { 1, 3, 6, 1, 4, 1, 311, 2, 2, 10 };
+static unsigned long KRB5_OID[7] = { 1, 2, 840, 113554, 1, 2, 2 };
+static unsigned long MSKRB5_OID[7] = { 1, 2, 840, 48018, 1, 2, 2 };
 
 /*
  * ASN.1 context.
@@ -457,6 +461,7 @@ decode_negTokenInit(unsigned char *security_blob, int length,
 	unsigned long *oid = NULL;
 	unsigned int cls, con, tag, oidlen, rc;
 	int use_ntlmssp = FALSE;
+	int use_kerberos = FALSE;
 
 	*secType = NTLM; /* BB eventually make Kerberos or NLTMSSP the default*/
 
@@ -545,18 +550,28 @@ decode_negTokenInit(unsigned char *security_blob, int length,
 				return 0;
 			}
 			if ((tag == ASN1_OJI) && (con == ASN1_PRI)) {
-				rc = asn1_oid_decode(&ctx, end, &oid, &oidlen);
-				if (rc) {
+				if (asn1_oid_decode(&ctx, end, &oid, &oidlen)) {
+
 					cFYI(1,
 					  ("OID len = %d oid = 0x%lx 0x%lx "
 					   "0x%lx 0x%lx",
 					   oidlen, *oid, *(oid + 1),
 					   *(oid + 2), *(oid + 3)));
-					rc = compare_oid(oid, oidlen,
-						 NTLMSSP_OID, NTLMSSP_OID_LEN);
-					kfree(oid);
-					if (rc)
+
+					if (compare_oid(oid, oidlen,
+							MSKRB5_OID,
+							MSKRB5_OID_LEN))
+						use_kerberos = TRUE;
+					else if (compare_oid(oid, oidlen,
+							     KRB5_OID,
+							     KRB5_OID_LEN))
+						use_kerberos = TRUE;
+					else if (compare_oid(oid, oidlen,
+							     NTLMSSP_OID,
+							     NTLMSSP_OID_LEN))
 						use_ntlmssp = TRUE;
+
+					kfree(oid);
 				}
 			} else {
 				cFYI(1, ("Should be an oid what is going on?"));
@@ -609,12 +624,10 @@ decode_negTokenInit(unsigned char *security_blob, int length,
 			 ctx.pointer));	/* is this UTF-8 or ASCII? */
 	}
 
-	/* if (use_kerberos)
-	   *secType = Kerberos
-	   else */
-	if (use_ntlmssp) {
+	if (use_kerberos)
+		*secType = Kerberos;
+	else if (use_ntlmssp)
 		*secType = NTLMSSP;
-	}
 
 	return 1;
 }
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 49ad995..d7d3433 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -649,8 +649,7 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
 						 count - 16,
 						 &server->secType);
 			if (rc == 1) {
-			/* BB Need to fill struct for sessetup here */
-				rc = -EOPNOTSUPP;
+				rc = 0;
 			} else {
 				rc = -EINVAL;
 			}
-- 
1.5.2.1