auth/kerberos: Move gse_get_session_key() to common code and use in gensec_gssapi

Thie ensures that both code bases use the same logic to determine the use
of NEW_SPNEGO.

Andrew Bartlett

auth/kerberos/gssapi_pac.c

@@ -22,6 +22,7 @@
 #ifdef HAVE_KRB5
 
 #include "libcli/auth/krb5_wrap.h"
+#include "lib/util/asn1.h"
 
 #if 0
 /* FIXME - need proper configure/waf test
@@ -47,6 +48,26 @@ const gss_OID_desc * const gss_mech_krb5_old          = krb5_gss_oid_array+1;
 const gss_OID_desc * const gss_mech_krb5_wrong        = krb5_gss_oid_array+2;
 #endif
 
+#ifndef GSS_KRB5_INQ_SSPI_SESSION_KEY_OID
+#define GSS_KRB5_INQ_SSPI_SESSION_KEY_OID_LENGTH 11
+#define GSS_KRB5_INQ_SSPI_SESSION_KEY_OID "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02\x05\x05"
+#endif
+
+gss_OID_desc gse_sesskey_inq_oid = {
+	GSS_KRB5_INQ_SSPI_SESSION_KEY_OID_LENGTH,
+	(void *)GSS_KRB5_INQ_SSPI_SESSION_KEY_OID
+};
+
+#ifndef GSS_KRB5_SESSION_KEY_ENCTYPE_OID
+#define GSS_KRB5_SESSION_KEY_ENCTYPE_OID_LENGTH 10
+#define GSS_KRB5_SESSION_KEY_ENCTYPE_OID  "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02\x04"
+#endif
+
+gss_OID_desc gse_sesskeytype_oid = {
+	GSS_KRB5_SESSION_KEY_ENCTYPE_OID_LENGTH,
+	(void *)GSS_KRB5_SESSION_KEY_ENCTYPE_OID
+};
+
 /* The Heimdal OID for getting the PAC */
 #define EXTRACT_PAC_AUTHZ_DATA_FROM_SEC_CONTEXT_OID_LENGTH 8
 /*					                EXTRACTION OID		   AUTHZ ID */
@@ -149,4 +170,96 @@ NTSTATUS gssapi_obtain_pac_blob(TALLOC_CTX *mem_ctx,
 #endif
 	return NT_STATUS_ACCESS_DENIED;
 }
+
+NTSTATUS gssapi_get_session_key(TALLOC_CTX *mem_ctx,
+				gss_ctx_id_t gssapi_context,
+				DATA_BLOB *session_key, 
+				uint32_t *keytype)
+{
+	OM_uint32 gss_min, gss_maj;
+	gss_buffer_set_t set = GSS_C_NO_BUFFER_SET;
+
+	gss_maj = gss_inquire_sec_context_by_oid(
+				&gss_min, gssapi_context,
+				&gse_sesskey_inq_oid, &set);
+	if (gss_maj) {
+		DEBUG(0, ("gss_inquire_sec_context_by_oid failed [%s]\n",
+			  gssapi_error_string(mem_ctx, gss_maj, gss_min, gss_mech_krb5)));
+		return NT_STATUS_NO_USER_SESSION_KEY;
+	}
+
+	if ((set == GSS_C_NO_BUFFER_SET) ||
+	    (set->count == 0)) {
+#ifdef HAVE_GSSKRB5_GET_SUBKEY
+		krb5_keyblock *subkey;
+		gss_maj = gsskrb5_get_subkey(&gss_min,
+					     gssapi_context,
+					     &subkey);
+		if (gss_maj != 0) {
+			DEBUG(1, ("NO session key for this mech\n"));
+			return NT_STATUS_NO_USER_SESSION_KEY;
+		}
+		if (session_key) {
+			*session_key = data_blob_talloc(mem_ctx,
+							KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
+		}
+		if (keytype) {
+			*keytype = KRB5_KEY_TYPE(subkey);
+		}
+		krb5_free_keyblock(NULL /* should be krb5_context */, subkey);
+		return NT_STATUS_OK;
+#else
+		DEBUG(0, ("gss_inquire_sec_context_by_oid returned unknown "
+			  "OID for data in results:\n"));
+		dump_data(1, (uint8_t *)set->elements[1].value,
+			     set->elements[1].length);
+		return NT_STATUS_NO_USER_SESSION_KEY;
+#endif
+	}
+
+	if (session_key) {
+		*session_key = data_blob_talloc(mem_ctx, set->elements[0].value,
+						set->elements[0].length);
+	}
+
+	if (keytype) {
+		char *oid;
+		char *p, *q = NULL;
+		
+		if (set->count < 2
+		    || memcmp(set->elements[1].value,
+			      gse_sesskeytype_oid.elements,
+			      gse_sesskeytype_oid.length) != 0) {
+			/* Perhaps a non-krb5 session key */
+			*keytype = 0;
+			gss_maj = gss_release_buffer_set(&gss_min, &set);
+			return NT_STATUS_OK;
+		}
+		if (!ber_read_OID_String(mem_ctx,
+					 data_blob_const(set->elements[1].value,
+							 set->elements[1].length), &oid)) {
+			TALLOC_FREE(oid);
+			gss_maj = gss_release_buffer_set(&gss_min, &set);
+			return NT_STATUS_INVALID_PARAMETER;
+		}
+		p = strrchr(oid, '.');
+		if (!p) {
+			TALLOC_FREE(oid);
+			gss_maj = gss_release_buffer_set(&gss_min, &set);
+			return NT_STATUS_INVALID_PARAMETER;
+		} else {
+			p++;
+			*keytype = strtoul(p, &q, 10);
+			if (q == NULL || *q != '\0') {
+				TALLOC_FREE(oid);
+				return NT_STATUS_INVALID_PARAMETER;
+			}
+		}
+		TALLOC_FREE(oid);
+	}
+	
+	gss_maj = gss_release_buffer_set(&gss_min, &set);
+	return NT_STATUS_OK;
+}
+
 #endif

libcli/auth/krb5_wrap.h

@@ -24,6 +24,18 @@
 struct PAC_SIGNATURE_DATA;
 struct PAC_DATA;
 
+#ifdef HAVE_KRB5_KEYBLOCK_KEYVALUE /* Heimdal */
+#define KRB5_KEY_TYPE(k)	((k)->keytype)
+#define KRB5_KEY_LENGTH(k)	((k)->keyvalue.length)
+#define KRB5_KEY_DATA(k)	((k)->keyvalue.data)
+#define KRB5_KEY_DATA_CAST	void
+#else /* MIT */
+#define KRB5_KEY_TYPE(k)	((k)->enctype)
+#define KRB5_KEY_LENGTH(k)	((k)->length)
+#define KRB5_KEY_DATA(k)	((k)->contents)
+#define KRB5_KEY_DATA_CAST	krb5_octet
+#endif /* HAVE_KRB5_KEYBLOCK_KEYVALUE */
+
 int create_kerberos_key_from_string_direct(krb5_context context,
 						  krb5_principal host_princ,
 						  krb5_data *password,
@@ -76,6 +88,11 @@ NTSTATUS gssapi_obtain_pac_blob(TALLOC_CTX *mem_ctx,
 				gss_ctx_id_t gssapi_context,
 				gss_name_t gss_client_name,
 				DATA_BLOB *pac_data);
+NTSTATUS gssapi_get_session_key(TALLOC_CTX *mem_ctx,
+				gss_ctx_id_t gssapi_context,
+				DATA_BLOB *session_key, 
+				uint32_t *keytype);
+
 DATA_BLOB gensec_gssapi_gen_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLOB *ticket, const uint8_t tok_id[2]);
 
 bool gensec_gssapi_parse_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLOB *blob, DATA_BLOB *ticket, uint8_t tok_id[2]);

source3/include/smb_krb5.h

@@ -66,18 +66,6 @@ typedef struct {
 #endif /* defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) */
 } smb_krb5_addresses;
 
-#ifdef HAVE_KRB5_KEYBLOCK_KEYVALUE /* Heimdal */
-#define KRB5_KEY_TYPE(k)	((k)->keytype)
-#define KRB5_KEY_LENGTH(k)	((k)->keyvalue.length)
-#define KRB5_KEY_DATA(k)	((k)->keyvalue.data)
-#define KRB5_KEY_DATA_CAST	void
-#else /* MIT */
-#define KRB5_KEY_TYPE(k)	((k)->enctype)
-#define KRB5_KEY_LENGTH(k)	((k)->length)
-#define KRB5_KEY_DATA(k)	((k)->contents)
-#define KRB5_KEY_DATA_CAST	krb5_octet
-#endif /* HAVE_KRB5_KEYBLOCK_KEYVALUE */
-
 #ifdef HAVE_KRB5_KEYTAB_ENTRY_KEY               /* MIT */
 #define KRB5_KT_KEY(k)		(&(k)->key)
 #elif HAVE_KRB5_KEYTAB_ENTRY_KEYBLOCK          /* Heimdal */

source3/librpc/crypto/gse.c

@@ -35,26 +35,6 @@
 #include "smb_krb5.h"
 #include "gse_krb5.h"
 
-#ifndef GSS_KRB5_INQ_SSPI_SESSION_KEY_OID
-#define GSS_KRB5_INQ_SSPI_SESSION_KEY_OID_LENGTH 11
-#define GSS_KRB5_INQ_SSPI_SESSION_KEY_OID "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02\x05\x05"
-#endif
-
-gss_OID_desc gse_sesskey_inq_oid = {
-	GSS_KRB5_INQ_SSPI_SESSION_KEY_OID_LENGTH,
-	(void *)GSS_KRB5_INQ_SSPI_SESSION_KEY_OID
-};
-
-#ifndef GSS_KRB5_SESSION_KEY_ENCTYPE_OID
-#define GSS_KRB5_SESSION_KEY_ENCTYPE_OID_LENGTH 10
-#define GSS_KRB5_SESSION_KEY_ENCTYPE_OID  "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02\x04"
-#endif
-
-gss_OID_desc gse_sesskeytype_oid = {
-	GSS_KRB5_SESSION_KEY_ENCTYPE_OID_LENGTH,
-	(void *)GSS_KRB5_SESSION_KEY_ENCTYPE_OID
-};
-
 static char *gse_errstr(TALLOC_CTX *mem_ctx, OM_uint32 maj, OM_uint32 min);
 
 struct gse_context {
@@ -563,96 +543,6 @@ done:
 	return errstr;
 }
 
-static NTSTATUS gse_get_session_key(TALLOC_CTX *mem_ctx,
-				    struct gse_context *gse_ctx, 
-				    DATA_BLOB *session_key, 
-				    uint32_t *keytype)
-{
-	OM_uint32 gss_min, gss_maj;
-	gss_buffer_set_t set = GSS_C_NO_BUFFER_SET;
-
-	gss_maj = gss_inquire_sec_context_by_oid(
-				&gss_min, gse_ctx->gssapi_context,
-				&gse_sesskey_inq_oid, &set);
-	if (gss_maj) {
-		DEBUG(0, ("gss_inquire_sec_context_by_oid failed [%s]\n",
-			  gse_errstr(talloc_tos(), gss_maj, gss_min)));
-		return NT_STATUS_NO_USER_SESSION_KEY;
-	}
-
-	if ((set == GSS_C_NO_BUFFER_SET) ||
-	    (set->count == 0)) {
-#ifdef HAVE_GSSKRB5_GET_SUBKEY
-		krb5_keyblock *subkey;
-		gss_maj = gsskrb5_get_subkey(&gss_min,
-					     gse_ctx->gssapi_context,
-					     &subkey);
-		if (gss_maj != 0) {
-			DEBUG(1, ("NO session key for this mech\n"));
-			return NT_STATUS_NO_USER_SESSION_KEY;
-		}
-		if (session_key) {
-			*session_key = data_blob_talloc(mem_ctx,
-							KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
-		}
-		if (keytype) {
-			*keytype = KRB5_KEY_TYPE(subkey);
-		}
-		krb5_free_keyblock(NULL /* should be krb5_context */, subkey);
-		return NT_STATUS_OK;
-#else
-		DEBUG(0, ("gss_inquire_sec_context_by_oid returned unknown "
-			  "OID for data in results:\n"));
-		dump_data(1, (uint8_t *)set->elements[1].value,
-			     set->elements[1].length);
-		return NT_STATUS_NO_USER_SESSION_KEY;
-#endif
-	}
-
-	if (session_key) {
-		*session_key = data_blob_talloc(mem_ctx, set->elements[0].value,
-						set->elements[0].length);
-	}
-
-	if (keytype) {
-		char *oid;
-		char *p, *q = NULL;
-		
-		if (set->count < 2
-		    || memcmp(set->elements[1].value,
-			      gse_sesskeytype_oid.elements,
-			      gse_sesskeytype_oid.length) != 0) {
-			/* Perhaps a non-krb5 session key */
-			*keytype = 0;
-			gss_maj = gss_release_buffer_set(&gss_min, &set);
-			return NT_STATUS_OK;
-		}
-		if (!ber_read_OID_String(talloc_tos(), 
-					 data_blob_const(set->elements[1].value,
-							 set->elements[1].length), &oid)) {
-			TALLOC_FREE(oid);
-			gss_maj = gss_release_buffer_set(&gss_min, &set);
-			return NT_STATUS_INVALID_PARAMETER;
-		}
-		p = strrchr(oid, '.');
-		if (!p) {
-			TALLOC_FREE(oid);
-			gss_maj = gss_release_buffer_set(&gss_min, &set);
-			return NT_STATUS_INVALID_PARAMETER;
-		} else {
-			p++;
-			*keytype = strtoul(p, &q, 10);
-			if (q == NULL || *q != '\0') {
-				return NT_STATUS_INVALID_PARAMETER;
-			}
-		}
-		TALLOC_FREE(oid);
-	}
-	
-	gss_maj = gss_release_buffer_set(&gss_min, &set);
-	return NT_STATUS_OK;
-}
-
 static size_t gse_get_signature_length(struct gse_context *gse_ctx,
 				       bool seal, size_t payload_size)
 {
@@ -1125,8 +1015,8 @@ static bool gensec_gse_have_feature(struct gensec_security *gensec_security,
 			return false;
 		}
 
-		status = gse_get_session_key(talloc_tos(), 
+		status = gssapi_get_session_key(talloc_tos(), 
-					   gse_ctx, NULL, &keytype);
+						gse_ctx->gssapi_context, NULL, &keytype);
 		/* 
 		 * We should do a proper sig on the mechListMic unless
 		 * we know we have to be backwards compatible with
@@ -1168,7 +1058,7 @@ static NTSTATUS gensec_gse_session_key(struct gensec_security *gensec_security,
 		talloc_get_type_abort(gensec_security->private_data,
 		struct gse_context);
 
-	return gse_get_session_key(mem_ctx, gse_ctx, session_key, NULL);
+	return gssapi_get_session_key(mem_ctx, gse_ctx->gssapi_context, session_key, NULL);
 }
 
 /* Get some basic (and authorization) information about the user on

source4/auth/gensec/gensec_gssapi.c

@@ -1229,6 +1229,7 @@ static bool gensec_gssapi_have_feature(struct gensec_security *gensec_security,
 	}
 	if (feature & GENSEC_FEATURE_NEW_SPNEGO) {
 		NTSTATUS status;
+		uint32_t keytype;
 
 		if (!(gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG)) {
 			return false;
@@ -1241,16 +1242,27 @@ static bool gensec_gssapi_have_feature(struct gensec_security *gensec_security,
 			return false;
 		}
 
-		status = gensec_gssapi_init_lucid(gensec_gssapi_state);
+		status = gssapi_get_session_key(gensec_gssapi_state,
-		if (!NT_STATUS_IS_OK(status)) {
+						gensec_gssapi_state->gssapi_context, NULL, &keytype);
-			return false;
+		/* 
+		 * We should do a proper sig on the mechListMic unless
+		 * we know we have to be backwards compatible with
+		 * earlier windows versions.  
+		 * 
+		 * Negotiating a non-krb5
+		 * mech for example should be regarded as having
+		 * NEW_SPNEGO
+		 */
+		if (NT_STATUS_IS_OK(status)) {
+			switch (keytype) {
+			case ENCTYPE_DES_CBC_CRC:
+			case ENCTYPE_DES_CBC_MD5:
+			case ENCTYPE_ARCFOUR_HMAC:
+			case ENCTYPE_DES3_CBC_SHA1:
+				return false;
+			}
 		}
-
+		return true;
-		if (gensec_gssapi_state->lucid->protocol == 1) {
-			return true;
-		}
-
-		return false;
 	}
 	/* We can always do async (rather than strict request/reply) packets.  */
 	if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
@@ -1271,30 +1283,7 @@ static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_securit
 {
 	struct gensec_gssapi_state *gensec_gssapi_state
 		= talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
-	OM_uint32 maj_stat, min_stat;
+	return gssapi_get_session_key(mem_ctx, gensec_gssapi_state->gssapi_context, session_key, NULL);
-	krb5_keyblock *subkey;
-
-	if (gensec_gssapi_state->sasl_state != STAGE_DONE) {
-		return NT_STATUS_NO_USER_SESSION_KEY;
-	}
-
-	maj_stat = gsskrb5_get_subkey(&min_stat,
-				      gensec_gssapi_state->gssapi_context,
-				      &subkey);
-	if (maj_stat != 0) {
-		DEBUG(1, ("NO session key for this mech\n"));
-		return NT_STATUS_NO_USER_SESSION_KEY;
-	}
-	
-	DEBUG(10, ("Got KRB5 session key of length %d%s\n",
-		   (int)KRB5_KEY_LENGTH(subkey),
-		   (gensec_gssapi_state->sasl_state == STAGE_DONE)?" (done)":""));
-	*session_key = data_blob_talloc(mem_ctx,
-					KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
-	krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context, subkey);
-	dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
-
-	return NT_STATUS_OK;
 }
 
 /* Get some basic (and authorization) information about the user on