lib: add new structures for srv6-locator (step2)

This commit is a part of FRRouting#5853 works that add new structures for
SRv6-locator. This structure will be used by zebra and another
routing daemon and its ZAPI messaging to manage SRv6-locator.
Encoder/decoder for ZAPI stream is also added by this commit.

Real configuration mechanism isn't implemented at this commit.
later commit add real configure implementation. This commit add only
SRv6-locator's structures and misc functions.

Signed-off-by: Hiroki Shirokura <slank.dev@gmail.com>

lib/srv6.c

@@ -22,6 +22,10 @@
 #include "srv6.h"
 #include "log.h"
 
+DEFINE_QOBJ_TYPE(srv6_locator)
+DEFINE_MTYPE_STATIC(LIB, SRV6_LOCATOR, "SRV6 locator")
+DEFINE_MTYPE_STATIC(LIB, SRV6_LOCATOR_CHUNK, "SRV6 locator chunk")
+
 const char *seg6local_action2str(uint32_t action)
 {
 	switch (action) {
@@ -117,3 +121,84 @@ const char *seg6local_context2str(char *str, size_t size,
 		return str;
 	}
 }
+
+struct srv6_locator *srv6_locator_alloc(const char *name)
+{
+	struct srv6_locator *locator = NULL;
+
+	locator = XCALLOC(MTYPE_SRV6_LOCATOR, sizeof(struct srv6_locator));
+	strlcpy(locator->name, name, sizeof(locator->name));
+	locator->chunks = list_new();
+	QOBJ_REG(locator, srv6_locator);
+	return locator;
+}
+
+struct srv6_locator_chunk *srv6_locator_chunk_alloc(void)
+{
+	struct srv6_locator_chunk *chunk = NULL;
+
+	chunk = XCALLOC(MTYPE_SRV6_LOCATOR_CHUNK,
+			sizeof(struct srv6_locator_chunk));
+	return chunk;
+}
+
+void srv6_locator_free(struct srv6_locator *locator)
+{
+	XFREE(MTYPE_SRV6_LOCATOR, locator);
+}
+
+void srv6_locator_chunk_free(struct srv6_locator_chunk *chunk)
+{
+	XFREE(MTYPE_SRV6_LOCATOR_CHUNK, chunk);
+}
+
+json_object *srv6_locator_chunk_json(const struct srv6_locator_chunk *chunk)
+{
+	char str[256];
+	json_object *jo_root = NULL;
+
+	jo_root = json_object_new_object();
+	prefix2str(&chunk->prefix, str, sizeof(str));
+	json_object_string_add(jo_root, "prefix", str);
+	json_object_string_add(jo_root, "proto",
+			       zebra_route_string(chunk->proto));
+
+	return jo_root;
+}
+
+json_object *srv6_locator_json(const struct srv6_locator *loc)
+{
+	char str[256];
+	struct listnode *node;
+	struct srv6_locator_chunk *chunk;
+	json_object *jo_root = NULL;
+	json_object *jo_chunk = NULL;
+	json_object *jo_chunks = NULL;
+
+	jo_root = json_object_new_object();
+
+	/* set name */
+	json_object_string_add(jo_root, "name", loc->name);
+
+	/* set prefix */
+	prefix2str(&loc->prefix, str, sizeof(str));
+	json_object_string_add(jo_root, "prefix", str);
+
+	/* set function_bits_length */
+	json_object_int_add(jo_root, "function_bits_length",
+			    loc->function_bits_length);
+
+	/* set status_up */
+	json_object_boolean_add(jo_root, "status_up",
+				loc->status_up);
+
+	/* set chunks */
+	jo_chunks = json_object_new_array();
+	json_object_object_add(jo_root, "chunks", jo_chunks);
+	for (ALL_LIST_ELEMENTS_RO((struct list *)loc->chunks, node, chunk)) {
+		jo_chunk = srv6_locator_chunk_json(chunk);
+		json_object_array_add(jo_chunks, jo_chunk);
+	}
+
+	return jo_root;
+}

lib/srv6.h

@@ -21,10 +21,14 @@
 #define _FRR_SRV6_H
 
 #include <zebra.h>
+#include "prefix.h"
+#include "json.h"
+
 #include <arpa/inet.h>
 #include <netinet/in.h>
 
 #define SRV6_MAX_SIDS 16
+#define SRV6_LOCNAME_SIZE 256
 
 #ifdef __cplusplus
 extern "C" {
@@ -69,6 +73,27 @@ struct seg6local_context {
 	uint32_t table;
 };
 
+struct srv6_locator {
+	char name[SRV6_LOCNAME_SIZE];
+	struct prefix_ipv6 prefix;
+	uint8_t function_bits_length;
+	int algonum;
+	uint64_t current;
+	bool status_up;
+	struct list *chunks;
+
+	QOBJ_FIELDS
+};
+DECLARE_QOBJ_TYPE(srv6_locator)
+
+struct srv6_locator_chunk {
+	uint8_t keep;
+	uint8_t proto;
+	uint16_t instance;
+	uint32_t session_id;
+	struct prefix_ipv6 prefix;
+};
+
 static inline const char *seg6_mode2str(enum seg6_mode_t mode)
 {
 	switch (mode) {
@@ -126,6 +151,13 @@ const char *seg6local_context2str(char *str, size_t size,
 int snprintf_seg6_segs(char *str,
 		size_t size, const struct seg6_segs *segs);
 
+extern struct srv6_locator *srv6_locator_alloc(const char *name);
+extern struct srv6_locator_chunk *srv6_locator_chunk_alloc(void);
+extern void srv6_locator_free(struct srv6_locator *locator);
+extern void srv6_locator_chunk_free(struct srv6_locator_chunk *chunk);
+json_object *srv6_locator_chunk_json(const struct srv6_locator_chunk *chunk);
+json_object *srv6_locator_json(const struct srv6_locator *loc);
+
 #ifdef __cplusplus
 }
 #endif

lib/zclient.c

@@ -41,6 +41,7 @@
 #include "lib_errors.h"
 #include "srte.h"
 #include "printfrr.h"
+#include "srv6.h"
 
 DEFINE_MTYPE_STATIC(LIB, ZCLIENT, "Zclient");
 DEFINE_MTYPE_STATIC(LIB, REDIST_INST, "Redistribution instance IDs");
@@ -2637,6 +2638,174 @@ int lm_label_manager_connect(struct zclient *zclient, int async)
 	return -1;
 }
 
+/**
+ * Connect to srv6 manager in a syncronous way
+ *
+ * It first writes the request to zcient output buffer and then
+ * immediately reads the answer from the input buffer.
+ *
+ * @param zclient Zclient used to connect to srv6 manager (zebra)
+ * @result Result of response
+ */
+int srv6_manager_connect(struct zclient *zclient)
+{
+	struct stream *s;
+	int ret, result = 0;
+	uint16_t cmd = ZEBRA_SRV6_MANAGER_CONNECT;
+
+	if (zclient_debug)
+		zlog_debug("Connecting to SRv6 Manager");
+
+	if (zclient->sock < 0) {
+		zlog_debug("%s: invalid zclient socket", __func__);
+		return -1;
+	}
+
+	/* send request */
+	s = zclient->obuf;
+	stream_reset(s);
+	zclient_create_header(s, cmd, VRF_DEFAULT);
+
+	stream_putc(s, zclient->redist_default); /* proto */
+	stream_putw(s, zclient->instance);       /* instance */
+	stream_putw_at(s, 0, stream_get_endp(s));
+	ret = writen(zclient->sock, s->data, stream_get_endp(s));
+	if (ret < 0) {
+		flog_err(EC_LIB_ZAPI_SOCKET, "Can't write to zclient sock");
+		close(zclient->sock);
+		zclient->sock = -1;
+		return -1;
+	}
+	if (ret == 0) {
+		flog_err(EC_LIB_ZAPI_SOCKET, "Zclient sock closed");
+		close(zclient->sock);
+		zclient->sock = -1;
+		return -1;
+	}
+	if (zclient_debug)
+		zlog_debug("SRv6 Manager connect request sent (%d bytes)", ret);
+
+	/* read response */
+	if (zclient_read_sync_response(zclient, cmd)
+	    != 0)
+		return -1;
+
+	s = zclient->ibuf;
+
+	/* read instance and proto */
+	uint8_t proto;
+	uint16_t instance;
+
+	STREAM_GETC(s, proto);
+	STREAM_GETW(s, instance);
+
+	/* sanity */
+	if (proto != zclient->redist_default)
+		flog_err(
+			EC_LIB_ZAPI_ENCODE,
+			"Wrong proto (%u) in SRv6 Manager connect response. Should be %u",
+			proto, zclient->redist_default);
+	if (instance != zclient->instance)
+		flog_err(
+			EC_LIB_ZAPI_ENCODE,
+			"Wrong instId (%u) in SRv6 Manager connect response. Should be %u",
+			instance, zclient->instance);
+
+	/* result code */
+	STREAM_GETC(s, result);
+	if (zclient_debug)
+		zlog_debug("SRv6 Manager connect-response received, result %u", result);
+
+	return (int)result;
+
+stream_failure:
+	return -1;
+}
+
+/**
+ * Function to request a srv6-locator chunk in an Asyncronous way
+ *
+ * It first writes the request to zclient output buffer and then
+ * immediately reads the answer from the input buffer.
+ *
+ * @param zclient Zclient used to connect to table manager (zebra)
+ * @param locator_name Name of SRv6-locator
+ * @result 0 on success, -1 otherwise
+ */
+int srv6_manager_get_locator_chunk(struct zclient *zclient,
+				   const char *locator_name)
+{
+	struct stream *s;
+	const size_t len = strlen(locator_name);
+
+	if (zclient_debug)
+		zlog_debug("Getting SRv6-Locator Chunk %s", locator_name);
+
+	if (zclient->sock < 0)
+		return -1;
+
+	/* send request */
+	s = zclient->obuf;
+	stream_reset(s);
+	zclient_create_header(s, ZEBRA_SRV6_MANAGER_GET_LOCATOR_CHUNK, VRF_DEFAULT);
+
+	/* proto */
+	stream_putc(s, zclient->redist_default);
+
+	/* instance */
+	stream_putw(s, zclient->instance);
+
+	/* locator_name */
+	stream_putw(s, len);
+	stream_put(s, locator_name, len);
+
+	/* Put length at the first point of the stream. */
+	stream_putw_at(s, 0, stream_get_endp(s));
+
+	return zclient_send_message(zclient);
+}
+
+/**
+ * Function to release a srv6-locator chunk
+ *
+ * @param zclient Zclient used to connect to table manager (zebra)
+ * @param locator_name Name of SRv6-locator
+ * @result 0 on success, -1 otherwise
+ */
+int srv6_manager_release_locator_chunk(struct zclient *zclient,
+				       const char *locator_name)
+{
+	struct stream *s;
+	const size_t len = strlen(locator_name);
+
+	if (zclient_debug)
+		zlog_debug("Releasing SRv6-Locator Chunk %s", locator_name);
+
+	if (zclient->sock < 0)
+		return -1;
+
+	/* send request */
+	s = zclient->obuf;
+	stream_reset(s);
+	zclient_create_header(s, ZEBRA_SRV6_MANAGER_RELEASE_LOCATOR_CHUNK,
+			      VRF_DEFAULT);
+
+	/* proto */
+	stream_putc(s, zclient->redist_default);
+
+	/* instance */
+	stream_putw(s, zclient->instance);
+
+	/* locator_name */
+	stream_putw(s, len);
+	stream_put(s, locator_name, len);
+
+	/* Put length at the first point of the stream. */
+	stream_putw_at(s, 0, stream_get_endp(s));
+
+	return zclient_send_message(zclient);
+}
+
 /*
  * Asynchronous label chunk request
  *
@@ -3927,6 +4096,21 @@ static int zclient_read(struct thread *thread)
 	case ZEBRA_MLAG_FORWARD_MSG:
 		zclient_mlag_handle_msg(command, zclient, length, vrf_id);
 		break;
+	case ZEBRA_SRV6_LOCATOR_ADD:
+		if (zclient->srv6_locator_add)
+			(*zclient->srv6_locator_add)(command, zclient, length,
+						     vrf_id);
+		break;
+	case ZEBRA_SRV6_LOCATOR_DELETE:
+		if (zclient->srv6_locator_delete)
+			(*zclient->srv6_locator_delete)(command, zclient,
+							length, vrf_id);
+		break;
+	case ZEBRA_SRV6_MANAGER_GET_LOCATOR_CHUNK:
+		if (zclient->process_srv6_locator_chunk)
+			(*zclient->process_srv6_locator_chunk)(command, zclient,
+							       length, vrf_id);
+		break;
 	case ZEBRA_ERROR:
 		zclient_handle_error(command, zclient, length, vrf_id);
 		break;