librpc/rpc: add dcerpc_[extract|construct]_bind_time_features()

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Guenther Deschner <gd@samba.org>

2 files changed, 93 insertions, 0 deletions

diff --git a/librpc/rpc/dcerpc_util.c b/librpc/rpc/dcerpc_util.c
index a4dd56986ae..696bcdae56e 100644
--- a/librpc/rpc/dcerpc_util.c
+++ b/librpc/rpc/dcerpc_util.c
@@ -652,3 +652,66 @@ bool dcerpc_sec_verification_trailer_check(
 
 	return true;
 }
+
+static const struct ndr_syntax_id dcerpc_bind_time_features_prefix  = {
+	.uuid = {
+		.time_low = 0x6cb71c2c,
+		.time_mid = 0x9812,
+		.time_hi_and_version = 0x4540,
+		.clock_seq = {0x00, 0x00},
+		.node = {0x00,0x00,0x00,0x00,0x00,0x00}
+	},
+	.if_version = 1,
+};
+
+bool dcerpc_extract_bind_time_features(struct ndr_syntax_id s, uint64_t *_features)
+{
+	uint8_t values[8];
+	uint64_t features = 0;
+
+	values[0] = s.uuid.clock_seq[0];
+	values[1] = s.uuid.clock_seq[1];
+	values[2] = s.uuid.node[0];
+	values[3] = s.uuid.node[1];
+	values[4] = s.uuid.node[2];
+	values[5] = s.uuid.node[3];
+	values[6] = s.uuid.node[4];
+	values[7] = s.uuid.node[5];
+
+	ZERO_STRUCT(s.uuid.clock_seq);
+	ZERO_STRUCT(s.uuid.node);
+
+	if (!ndr_syntax_id_equal(&s, &dcerpc_bind_time_features_prefix)) {
+		if (_features != NULL) {
+			*_features = 0;
+		}
+		return false;
+	}
+
+	features = BVAL(values, 0);
+
+	if (_features != NULL) {
+		*_features = features;
+	}
+
+	return true;
+}
+
+struct ndr_syntax_id dcerpc_construct_bind_time_features(uint64_t features)
+{
+	struct ndr_syntax_id s = dcerpc_bind_time_features_prefix;
+	uint8_t values[8];
+
+	SBVAL(values, 0, features);
+
+	s.uuid.clock_seq[0] = values[0];
+	s.uuid.clock_seq[1] = values[1];
+	s.uuid.node[0]      = values[2];
+	s.uuid.node[1]      = values[3];
+	s.uuid.node[2]      = values[4];
+	s.uuid.node[3]      = values[5];
+	s.uuid.node[4]      = values[6];
+	s.uuid.node[5]      = values[7];
+
+	return s;
+}
diff --git a/librpc/rpc/rpc_common.h b/librpc/rpc/rpc_common.h
index 4210228d1d1..28600c9da7c 100644
--- a/librpc/rpc/rpc_common.h
+++ b/librpc/rpc/rpc_common.h
@@ -373,6 +373,36 @@ bool dcerpc_sec_verification_trailer_check(
 		const struct dcerpc_sec_vt_pcontext *pcontext,
 		const struct dcerpc_sec_vt_header2 *header2);
 
+/**
+ * @brief check and optionally extract the Bind Time Features from
+ * the given ndr_syntax_id.
+ *
+ * <a href="http://msdn.microsoft.com/en-us/library/cc243715.aspx">MS-RPCE 3.3.1.5.3 Bind Time Feature Negotiation</a>.
+ *
+ * @param[in]  s the syntax that should be checked.
+ *
+ * @param[out] features This is optional, it will be filled with the extracted
+ *                      features the on success, otherwise it's filled with 0.
+ *
+ * @return true if the syntax matches the 6CB71C2C-9812-4540 prefix with version 1, false otherwise.
+ *
+ * @see dcerpc_construct_bind_time_features
+ */
+bool dcerpc_extract_bind_time_features(struct ndr_syntax_id syntax, uint64_t *features);
+
+/**
+ * @brief Construct a ndr_syntax_id used for Bind Time Features Negotiation.
+ *
+ * <a href="http://msdn.microsoft.com/en-us/library/cc243715.aspx">MS-RPCE 3.3.1.5.3 Bind Time Feature Negotiation</a>.
+ *
+ * @param[in] features The supported features.
+ *
+ * @return The ndr_syntax_id with the given features.
+ *
+ * @see dcerpc_extract_bind_time_features
+ */
+struct ndr_syntax_id dcerpc_construct_bind_time_features(uint64_t features);
+
 #define DCERPC_AUTH_PAD_LENGTH(stub_length) (\
 	(((stub_length) % DCERPC_AUTH_PAD_ALIGNMENT) > 0)?\
 	(DCERPC_AUTH_PAD_ALIGNMENT - (stub_length) % DCERPC_AUTH_PAD_ALIGNMENT):\