[mirror_frr.git] / lib / yang_translator.c

/*
 * Copyright (C) 2018  NetDEF, Inc.
 *                     Renato Westphal
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; see the file COPYING; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <zebra.h>

#include "log.h"
#include "lib_errors.h"
#include "hash.h"
#include "yang.h"
#include "yang_translator.h"
#include "frrstr.h"

DEFINE_MTYPE_STATIC(LIB, YANG_TRANSLATOR, "YANG Translator");
DEFINE_MTYPE_STATIC(LIB, YANG_TRANSLATOR_MODULE, "YANG Translator Module");
DEFINE_MTYPE_STATIC(LIB, YANG_TRANSLATOR_MAPPING, "YANG Translator Mapping");

/* Generate the yang_translators tree. */
static inline int yang_translator_compare(const struct yang_translator *a,
					  const struct yang_translator *b)
{
	return strcmp(a->family, b->family);
}
RB_GENERATE(yang_translators, yang_translator, entry, yang_translator_compare)

struct yang_translators yang_translators = RB_INITIALIZER(&yang_translators);

/* Separate libyang context for the translator module. */
static struct ly_ctx *ly_translator_ctx;

static unsigned int
yang_translator_validate(struct yang_translator *translator);
static unsigned int yang_module_nodes_count(const struct lys_module *module);

struct yang_mapping_node {
	char xpath_from_canonical[XPATH_MAXLEN];
	char xpath_from_fmt[XPATH_MAXLEN];
	char xpath_to_fmt[XPATH_MAXLEN];
};

static bool yang_mapping_hash_cmp(const void *value1, const void *value2)
{
	const struct yang_mapping_node *c1 = value1;
	const struct yang_mapping_node *c2 = value2;

	return strmatch(c1->xpath_from_canonical, c2->xpath_from_canonical);
}

static unsigned int yang_mapping_hash_key(const void *value)
{
	return string_hash_make(value);
}

static void *yang_mapping_hash_alloc(void *p)
{
	struct yang_mapping_node *new, *key = p;

	new = XCALLOC(MTYPE_YANG_TRANSLATOR_MAPPING, sizeof(*new));
	strlcpy(new->xpath_from_canonical, key->xpath_from_canonical,
		sizeof(new->xpath_from_canonical));

	return new;
}

static void yang_mapping_hash_free(void *arg)
{
	XFREE(MTYPE_YANG_TRANSLATOR_MAPPING, arg);
}

static struct yang_mapping_node *
yang_mapping_lookup(const struct yang_translator *translator, int dir,
		    const char *xpath)
{
	struct yang_mapping_node s;

	strlcpy(s.xpath_from_canonical, xpath, sizeof(s.xpath_from_canonical));
	return hash_lookup(translator->mappings[dir], &s);
}

static void yang_mapping_add(struct yang_translator *translator, int dir,
			     const struct lysc_node *snode,
			     const char *xpath_from_fmt,
			     const char *xpath_to_fmt)
{
	struct yang_mapping_node *mapping, s;

	yang_snode_get_path(snode, YANG_PATH_DATA, s.xpath_from_canonical,
			    sizeof(s.xpath_from_canonical));
	mapping = hash_get(translator->mappings[dir], &s,
			   yang_mapping_hash_alloc);
	strlcpy(mapping->xpath_from_fmt, xpath_from_fmt,
		sizeof(mapping->xpath_from_fmt));
	strlcpy(mapping->xpath_to_fmt, xpath_to_fmt,
		sizeof(mapping->xpath_to_fmt));

	const char *keys[] = {"KEY1", "KEY2", "KEY3", "KEY4"};
	char *xpfmt;

	for (unsigned int i = 0; i < array_size(keys); i++) {
		xpfmt = frrstr_replace(mapping->xpath_from_fmt, keys[i],
				       "%[^']");
		strlcpy(mapping->xpath_from_fmt, xpfmt,
			sizeof(mapping->xpath_from_fmt));
		XFREE(MTYPE_TMP, xpfmt);
	}

	for (unsigned int i = 0; i < array_size(keys); i++) {
		xpfmt = frrstr_replace(mapping->xpath_to_fmt, keys[i], "%s");
		strlcpy(mapping->xpath_to_fmt, xpfmt,
			sizeof(mapping->xpath_to_fmt));
		XFREE(MTYPE_TMP, xpfmt);
	}
}

struct yang_translator *yang_translator_load(const char *path)
{
	struct yang_translator *translator;
	struct yang_tmodule *tmodule;
	const char *family;
	struct lyd_node *dnode;
	struct ly_set *set;
	struct listnode *ln;
	LY_ERR err;

	/* Load module translator (JSON file). */
	err = lyd_parse_data_path(ly_translator_ctx, path, LYD_JSON,
				  LYD_PARSE_NO_STATE, LYD_VALIDATE_NO_STATE,
				  &dnode);
	if (err) {
		flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
			  "%s: lyd_parse_path() failed: %d", __func__, err);
		return NULL;
	}
	dnode = yang_dnode_get(dnode,
			       "/frr-module-translator:frr-module-translator");
	/*
	 * libyang guarantees the "frr-module-translator" top-level container is
	 * always present since it contains mandatory child nodes.
	 */
	assert(dnode);

	family = yang_dnode_get_string(dnode, "./family");
	translator = yang_translator_find(family);
	if (translator != NULL) {
		flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
			  "%s: module translator \"%s\" is loaded already",
			  __func__, family);
		return NULL;
	}

	translator = XCALLOC(MTYPE_YANG_TRANSLATOR, sizeof(*translator));
	strlcpy(translator->family, family, sizeof(translator->family));
	translator->modules = list_new();
	for (size_t i = 0; i < YANG_TRANSLATE_MAX; i++)
		translator->mappings[i] = hash_create(yang_mapping_hash_key,
						      yang_mapping_hash_cmp,
						      "YANG translation table");
	RB_INSERT(yang_translators, &yang_translators, translator);

	/* Initialize the translator libyang context. */
	translator->ly_ctx = yang_ctx_new_setup(false, false);
	if (!translator->ly_ctx) {
		flog_warn(EC_LIB_LIBYANG, "%s: ly_ctx_new() failed", __func__);
		goto error;
	}

	/* Load modules */
	if (lyd_find_xpath(dnode, "./module", &set) != LY_SUCCESS)
		assert(0); /* XXX libyang2: old ly1 code asserted success */

	for (size_t i = 0; i < set->count; i++) {
		const char *module_name;

		tmodule =
			XCALLOC(MTYPE_YANG_TRANSLATOR_MODULE, sizeof(*tmodule));

		module_name = yang_dnode_get_string(set->dnodes[i], "./name");
		tmodule->module = ly_ctx_load_module(translator->ly_ctx,
						     module_name, NULL, NULL);
		if (!tmodule->module) {
			flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
				  "%s: failed to load module: %s", __func__,
				  module_name);
			ly_set_free(set, NULL);
			goto error;
		}
	}

	/* Count nodes in modules. */
	for (ALL_LIST_ELEMENTS_RO(translator->modules, ln, tmodule)) {
		tmodule->nodes_before_deviations =
			yang_module_nodes_count(tmodule->module);
	}

	/* Load the deviations and count nodes again */
	for (ALL_LIST_ELEMENTS_RO(translator->modules, ln, tmodule)) {
		const char *module_name = tmodule->module->name;
		tmodule->deviations = ly_ctx_load_module(
			translator->ly_ctx, module_name, NULL, NULL);
		if (!tmodule->deviations) {
			flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
				  "%s: failed to load module: %s", __func__,
				  module_name);
			ly_set_free(set, NULL);
			goto error;
		}

		tmodule->nodes_after_deviations =
			yang_module_nodes_count(tmodule->module);
	}
	ly_set_free(set, NULL);

	/* Calculate the coverage. */
	for (ALL_LIST_ELEMENTS_RO(translator->modules, ln, tmodule)) {
		tmodule->coverage = ((double)tmodule->nodes_after_deviations
				     / (double)tmodule->nodes_before_deviations)
				    * 100;
	}

	/* Load mappings. */
	if (lyd_find_xpath(dnode, "./module/mappings", &set) != LY_SUCCESS)
		assert(0); /* XXX libyang2: old ly1 code asserted success */
	for (size_t i = 0; i < set->count; i++) {
		const char *xpath_custom, *xpath_native;
		const struct lysc_node *snode_custom, *snode_native;

		xpath_custom =
			yang_dnode_get_string(set->dnodes[i], "./custom");

		snode_custom = lys_find_path(translator->ly_ctx, NULL,
					     xpath_custom, 0);
		if (!snode_custom) {
			flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
				  "%s: unknown data path: %s", __func__,
				  xpath_custom);
			ly_set_free(set, NULL);
			goto error;
		}

		xpath_native =
			yang_dnode_get_string(set->dnodes[i], "./native");
		snode_native =
			lys_find_path(ly_native_ctx, NULL, xpath_native, 0);
		if (!snode_native) {
			flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
				  "%s: unknown data path: %s", __func__,
				  xpath_native);
			ly_set_free(set, NULL);
			goto error;
		}

		yang_mapping_add(translator, YANG_TRANSLATE_TO_NATIVE,
				 snode_custom, xpath_custom, xpath_native);
		yang_mapping_add(translator, YANG_TRANSLATE_FROM_NATIVE,
				 snode_native, xpath_native, xpath_custom);
	}
	ly_set_free(set, NULL);

	/* Validate mappings. */
	if (yang_translator_validate(translator) != 0)
		goto error;

	yang_dnode_free(dnode);

	return translator;

error:
	yang_dnode_free(dnode);
	yang_translator_unload(translator);

	return NULL;
}

static void yang_tmodule_delete(struct yang_tmodule *tmodule)
{
	XFREE(MTYPE_YANG_TRANSLATOR_MODULE, tmodule);
}

void yang_translator_unload(struct yang_translator *translator)
{
	for (size_t i = 0; i < YANG_TRANSLATE_MAX; i++)
		hash_clean(translator->mappings[i], yang_mapping_hash_free);
	translator->modules->del = (void (*)(void *))yang_tmodule_delete;
	list_delete(&translator->modules);
	ly_ctx_destroy(translator->ly_ctx);
	RB_REMOVE(yang_translators, &yang_translators, translator);
	XFREE(MTYPE_YANG_TRANSLATOR, translator);
}

struct yang_translator *yang_translator_find(const char *family)
{
	struct yang_translator s;

	strlcpy(s.family, family, sizeof(s.family));
	return RB_FIND(yang_translators, &yang_translators, &s);
}

enum yang_translate_result
yang_translate_xpath(const struct yang_translator *translator, int dir,
		     char *xpath, size_t xpath_len)
{
	struct ly_ctx *ly_ctx;
	const struct lysc_node *snode;
	struct yang_mapping_node *mapping;
	char xpath_canonical[XPATH_MAXLEN];
	char keys[4][LIST_MAXKEYLEN];
	int n;

	if (dir == YANG_TRANSLATE_TO_NATIVE)
		ly_ctx = translator->ly_ctx;
	else
		ly_ctx = ly_native_ctx;

	snode = lys_find_path(ly_ctx, NULL, xpath, 0);
	if (!snode) {
		flog_warn(EC_LIB_YANG_TRANSLATION_ERROR,
			  "%s: unknown data path: %s", __func__, xpath);
		return YANG_TRANSLATE_FAILURE;
	}

	yang_snode_get_path(snode, YANG_PATH_DATA, xpath_canonical,
			    sizeof(xpath_canonical));
	mapping = yang_mapping_lookup(translator, dir, xpath_canonical);
	if (!mapping)
		return YANG_TRANSLATE_NOTFOUND;

#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wformat-nonliteral"
	/* processing format strings from mapping node... */
	n = sscanf(xpath, mapping->xpath_from_fmt, keys[0], keys[1], keys[2],
		   keys[3]);
#pragma GCC diagnostic pop
	if (n < 0) {
		flog_warn(EC_LIB_YANG_TRANSLATION_ERROR,
			  "%s: sscanf() failed: %s", __func__,
			  safe_strerror(errno));
		return YANG_TRANSLATE_FAILURE;
	}

#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wformat-nonliteral"
	/* processing format strings from mapping node... */
	snprintf(xpath, xpath_len, mapping->xpath_to_fmt, keys[0], keys[1],
		 keys[2], keys[3]);
#pragma GCC diagnostic pop

	return YANG_TRANSLATE_SUCCESS;
}

int yang_translate_dnode(const struct yang_translator *translator, int dir,
			 struct lyd_node **dnode)
{
	struct ly_ctx *ly_ctx;
	struct lyd_node *new;
	struct lyd_node *root, *dnode_iter;

	/* Create new libyang data node to hold the translated data. */
	if (dir == YANG_TRANSLATE_TO_NATIVE)
		ly_ctx = ly_native_ctx;
	else
		ly_ctx = translator->ly_ctx;
	new = yang_dnode_new(ly_ctx, false);

	/* Iterate over all nodes from the data tree. */
	LY_LIST_FOR (*dnode, root) {
		LYD_TREE_DFS_BEGIN (root, dnode_iter) {
			char xpath[XPATH_MAXLEN];
			enum yang_translate_result ret;

			yang_dnode_get_path(dnode_iter, xpath, sizeof(xpath));
			ret = yang_translate_xpath(translator, dir, xpath,
						   sizeof(xpath));
			switch (ret) {
			case YANG_TRANSLATE_SUCCESS:
				break;
			case YANG_TRANSLATE_NOTFOUND:
				goto next;
			case YANG_TRANSLATE_FAILURE:
				goto error;
			}

			/* Create new node in the tree of translated data. */
			if (lyd_new_path(new, ly_ctx, xpath,
					 (void *)yang_dnode_get_string(
						 dnode_iter, NULL),
					 LYD_NEW_PATH_UPDATE, NULL)) {
				flog_err(EC_LIB_LIBYANG,
					 "%s: lyd_new_path() failed", __func__);
				goto error;
			}

		next:
			LYD_TREE_DFS_END(root, dnode_iter);
		}
	}

	/* Replace dnode by the new translated dnode. */
	yang_dnode_free(*dnode);
	*dnode = new;

	return YANG_TRANSLATE_SUCCESS;

error:
	yang_dnode_free(new);

	return YANG_TRANSLATE_FAILURE;
}

struct translator_validate_args {
	struct yang_translator *translator;
	unsigned int errors;
};

static int yang_translator_validate_cb(const struct lysc_node *snode_custom,
				       void *arg)
{
	struct translator_validate_args *args = arg;
	struct yang_mapping_node *mapping;
	const struct lysc_node *snode_native;
	const struct lysc_type *stype_custom, *stype_native;
	char xpath[XPATH_MAXLEN];

	yang_snode_get_path(snode_custom, YANG_PATH_DATA, xpath, sizeof(xpath));
	mapping = yang_mapping_lookup(args->translator,
				      YANG_TRANSLATE_TO_NATIVE, xpath);
	if (!mapping) {
		flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
			  "%s: missing mapping for \"%s\"", __func__, xpath);
		args->errors += 1;
		return YANG_ITER_CONTINUE;
	}

	snode_native =
		lys_find_path(ly_native_ctx, NULL, mapping->xpath_to_fmt, 0);
	assert(snode_native);

	/* Check if the YANG types are compatible. */
	stype_custom = yang_snode_get_type(snode_custom);
	stype_native = yang_snode_get_type(snode_native);
	if (stype_custom && stype_native) {
		if (stype_custom->basetype != stype_native->basetype) {
			flog_warn(
				EC_LIB_YANG_TRANSLATOR_LOAD,
				"%s: YANG types are incompatible (xpath: \"%s\")",
				__func__, xpath);
			args->errors += 1;
			return YANG_ITER_CONTINUE;
		}

		/* TODO: check if the value spaces are identical. */
	}

	return YANG_ITER_CONTINUE;
}

/*
 * Check if the modules from the translator have a mapping for all of their
 * schema nodes (after loading the deviations).
 */
static unsigned int yang_translator_validate(struct yang_translator *translator)
{
	struct yang_tmodule *tmodule;
	struct listnode *ln;
	struct translator_validate_args args;

	args.translator = translator;
	args.errors = 0;

	for (ALL_LIST_ELEMENTS_RO(translator->modules, ln, tmodule)) {
		yang_snodes_iterate(tmodule->module,
				    yang_translator_validate_cb,
				    YANG_ITER_FILTER_NPCONTAINERS
					    | YANG_ITER_FILTER_LIST_KEYS
					    | YANG_ITER_FILTER_INPUT_OUTPUT,
				    &args);
	}

	if (args.errors)
		flog_warn(
			EC_LIB_YANG_TRANSLATOR_LOAD,
			"%s: failed to validate \"%s\" module translator: %u error(s)",
			__func__, translator->family, args.errors);

	return args.errors;
}

static int yang_module_nodes_count_cb(const struct lysc_node *snode, void *arg)
{
	unsigned int *total = arg;

	*total += 1;

	return YANG_ITER_CONTINUE;
}

/* Calculate the number of nodes for the given module. */
static unsigned int yang_module_nodes_count(const struct lys_module *module)
{
	unsigned int total = 0;

	yang_snodes_iterate(module, yang_module_nodes_count_cb,
			    YANG_ITER_FILTER_NPCONTAINERS
				    | YANG_ITER_FILTER_LIST_KEYS
				    | YANG_ITER_FILTER_INPUT_OUTPUT,
			    &total);

	return total;
}

void yang_translator_init(void)
{
	ly_translator_ctx = yang_ctx_new_setup(true, false);
	if (!ly_translator_ctx) {
		flog_err(EC_LIB_LIBYANG, "%s: ly_ctx_new() failed", __func__);
		exit(1);
	}

	if (!ly_ctx_load_module(ly_translator_ctx, "frr-module-translator",
				NULL, NULL)) {
		flog_err(
			EC_LIB_YANG_MODULE_LOAD,
			"%s: failed to load the \"frr-module-translator\" module",
			__func__);
		exit(1);
	}
}

void yang_translator_terminate(void)
{
	while (!RB_EMPTY(yang_translators, &yang_translators)) {
		struct yang_translator *translator;

		translator = RB_ROOT(yang_translators, &yang_translators);
		yang_translator_unload(translator);
	}

	ly_ctx_destroy(ly_translator_ctx);
}
Commit	Line	Data
1c2facd1 RW	1	/*
	2	* Copyright (C) 2018 NetDEF, Inc.
	3	* Renato Westphal
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License as published by the Free
	7	* Software Foundation; either version 2 of the License, or (at your option)
	8	* any later version.
	9	*
	10	* This program is distributed in the hope that it will be useful, but WITHOUT
	11	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	12	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	13	* more details.
	14	*
	15	* You should have received a copy of the GNU General Public License along
	16	* with this program; see the file COPYING; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	18	*/
	19
	20	#include <zebra.h>
	21
	22	#include "log.h"
	23	#include "lib_errors.h"
	24	#include "hash.h"
	25	#include "yang.h"
	26	#include "yang_translator.h"
f9ce1142	27	#include "frrstr.h"
1c2facd1	28
bf8d3d6a DL	29	DEFINE_MTYPE_STATIC(LIB, YANG_TRANSLATOR, "YANG Translator");
	30	DEFINE_MTYPE_STATIC(LIB, YANG_TRANSLATOR_MODULE, "YANG Translator Module");
	31	DEFINE_MTYPE_STATIC(LIB, YANG_TRANSLATOR_MAPPING, "YANG Translator Mapping");
1c2facd1 RW	32
	33	/* Generate the yang_translators tree. */
	34	static inline int yang_translator_compare(const struct yang_translator *a,
	35	const struct yang_translator *b)
	36	{
	37	return strcmp(a->family, b->family);
	38	}
	39	RB_GENERATE(yang_translators, yang_translator, entry, yang_translator_compare)
	40
	41	struct yang_translators yang_translators = RB_INITIALIZER(&yang_translators);
	42
	43	/* Separate libyang context for the translator module. */
	44	static struct ly_ctx *ly_translator_ctx;
	45
	46	static unsigned int
	47	yang_translator_validate(struct yang_translator *translator);
	48	static unsigned int yang_module_nodes_count(const struct lys_module *module);
1c2facd1 RW	49
	50	struct yang_mapping_node {
	51	char xpath_from_canonical[XPATH_MAXLEN];
	52	char xpath_from_fmt[XPATH_MAXLEN];
	53	char xpath_to_fmt[XPATH_MAXLEN];
	54	};
	55
	56	static bool yang_mapping_hash_cmp(const void value1, const void value2)
	57	{
	58	const struct yang_mapping_node *c1 = value1;
	59	const struct yang_mapping_node *c2 = value2;
	60
	61	return strmatch(c1->xpath_from_canonical, c2->xpath_from_canonical);
	62	}
	63
d8b87afe	64	static unsigned int yang_mapping_hash_key(const void *value)
1c2facd1 RW	65	{
	66	return string_hash_make(value);
	67	}
	68
	69	static void yang_mapping_hash_alloc(void p)
	70	{
	71	struct yang_mapping_node new, key = p;
	72
	73	new = XCALLOC(MTYPE_YANG_TRANSLATOR_MAPPING, sizeof(*new));
	74	strlcpy(new->xpath_from_canonical, key->xpath_from_canonical,
	75	sizeof(new->xpath_from_canonical));
	76
	77	return new;
	78	}
	79
	80	static void yang_mapping_hash_free(void *arg)
	81	{
	82	XFREE(MTYPE_YANG_TRANSLATOR_MAPPING, arg);
	83	}
	84
	85	static struct yang_mapping_node *
	86	yang_mapping_lookup(const struct yang_translator *translator, int dir,
	87	const char *xpath)
	88	{
	89	struct yang_mapping_node s;
	90
	91	strlcpy(s.xpath_from_canonical, xpath, sizeof(s.xpath_from_canonical));
	92	return hash_lookup(translator->mappings[dir], &s);
	93	}
	94
	95	static void yang_mapping_add(struct yang_translator *translator, int dir,
3bb513c3	96	const struct lysc_node *snode,
1c2facd1 RW	97	const char *xpath_from_fmt,
	98	const char *xpath_to_fmt)
	99	{
	100	struct yang_mapping_node *mapping, s;
	101
	102	yang_snode_get_path(snode, YANG_PATH_DATA, s.xpath_from_canonical,
	103	sizeof(s.xpath_from_canonical));
	104	mapping = hash_get(translator->mappings[dir], &s,
	105	yang_mapping_hash_alloc);
	106	strlcpy(mapping->xpath_from_fmt, xpath_from_fmt,
	107	sizeof(mapping->xpath_from_fmt));
	108	strlcpy(mapping->xpath_to_fmt, xpath_to_fmt,
	109	sizeof(mapping->xpath_to_fmt));
f9ce1142 QY	110
	111	const char *keys[] = {"KEY1", "KEY2", "KEY3", "KEY4"};
	112	char *xpfmt;
	113
	114	for (unsigned int i = 0; i < array_size(keys); i++) {
	115	xpfmt = frrstr_replace(mapping->xpath_from_fmt, keys[i],
	116	"%[^']");
	117	strlcpy(mapping->xpath_from_fmt, xpfmt,
	118	sizeof(mapping->xpath_from_fmt));
	119	XFREE(MTYPE_TMP, xpfmt);
	120	}
	121
	122	for (unsigned int i = 0; i < array_size(keys); i++) {
	123	xpfmt = frrstr_replace(mapping->xpath_to_fmt, keys[i], "%s");
	124	strlcpy(mapping->xpath_to_fmt, xpfmt,
	125	sizeof(mapping->xpath_to_fmt));
	126	XFREE(MTYPE_TMP, xpfmt);
	127	}
1c2facd1 RW	128	}
	129
	130	struct yang_translator yang_translator_load(const char path)
	131	{
	132	struct yang_translator *translator;
	133	struct yang_tmodule *tmodule;
	134	const char *family;
	135	struct lyd_node *dnode;
	136	struct ly_set *set;
	137	struct listnode *ln;
3bb513c3	138	LY_ERR err;
1c2facd1 RW	139
1c2facd1 RW	140	/* Load module translator (JSON file). */
3bb513c3 CH	141	err = lyd_parse_data_path(ly_translator_ctx, path, LYD_JSON,
	142	LYD_PARSE_NO_STATE, LYD_VALIDATE_NO_STATE,
	143	&dnode);
	144	if (err) {
1c2facd1	145	flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
3bb513c3	146	"%s: lyd_parse_path() failed: %d", __func__, err);
1c2facd1 RW	147	return NULL;
	148	}
	149	dnode = yang_dnode_get(dnode,
	150	"/frr-module-translator:frr-module-translator");
	151	/*
	152	* libyang guarantees the "frr-module-translator" top-level container is
	153	* always present since it contains mandatory child nodes.
	154	*/
	155	assert(dnode);
	156
	157	family = yang_dnode_get_string(dnode, "./family");
	158	translator = yang_translator_find(family);
	159	if (translator != NULL) {
	160	flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
	161	"%s: module translator \"%s\" is loaded already",
	162	__func__, family);
	163	return NULL;
	164	}
	165
	166	translator = XCALLOC(MTYPE_YANG_TRANSLATOR, sizeof(*translator));
	167	strlcpy(translator->family, family, sizeof(translator->family));
	168	translator->modules = list_new();
	169	for (size_t i = 0; i < YANG_TRANSLATE_MAX; i++)
	170	translator->mappings[i] = hash_create(yang_mapping_hash_key,
	171	yang_mapping_hash_cmp,
	172	"YANG translation table");
	173	RB_INSERT(yang_translators, &yang_translators, translator);
	174
	175	/* Initialize the translator libyang context. */
3bb513c3	176	translator->ly_ctx = yang_ctx_new_setup(false, false);
1c2facd1 RW	177	if (!translator->ly_ctx) {
	178	flog_warn(EC_LIB_LIBYANG, "%s: ly_ctx_new() failed", __func__);
	179	goto error;
	180	}
1c2facd1	181
3bb513c3 CH	182	/* Load modules */
	183	if (lyd_find_xpath(dnode, "./module", &set) != LY_SUCCESS)
	184	assert(0); /* XXX libyang2: old ly1 code asserted success */
	185
	186	for (size_t i = 0; i < set->count; i++) {
1c2facd1 RW	187	const char *module_name;
	188
	189	tmodule =
	190	XCALLOC(MTYPE_YANG_TRANSLATOR_MODULE, sizeof(*tmodule));
	191
3bb513c3	192	module_name = yang_dnode_get_string(set->dnodes[i], "./name");
1c2facd1	193	tmodule->module = ly_ctx_load_module(translator->ly_ctx,
3bb513c3	194	module_name, NULL, NULL);
1c2facd1 RW	195	if (!tmodule->module) {
	196	flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
	197	"%s: failed to load module: %s", __func__,
	198	module_name);
3bb513c3	199	ly_set_free(set, NULL);
1c2facd1 RW	200	goto error;
1c2facd1 RW	201	}
3bb513c3	202	}
1c2facd1	203
3bb513c3 CH	204	/* Count nodes in modules. */
	205	for (ALL_LIST_ELEMENTS_RO(translator->modules, ln, tmodule)) {
	206	tmodule->nodes_before_deviations =
	207	yang_module_nodes_count(tmodule->module);
	208	}
	209
	210	/* Load the deviations and count nodes again */
	211	for (ALL_LIST_ELEMENTS_RO(translator->modules, ln, tmodule)) {
	212	const char *module_name = tmodule->module->name;
	213	tmodule->deviations = ly_ctx_load_module(
	214	translator->ly_ctx, module_name, NULL, NULL);
1c2facd1 RW	215	if (!tmodule->deviations) {
	216	flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
	217	"%s: failed to load module: %s", __func__,
	218	module_name);
3bb513c3	219	ly_set_free(set, NULL);
1c2facd1 RW	220	goto error;
1c2facd1 RW	221	}
1c2facd1	222
3bb513c3 CH	223	tmodule->nodes_after_deviations =
3bb513c3 CH	224	yang_module_nodes_count(tmodule->module);
1c2facd1	225	}
3bb513c3	226	ly_set_free(set, NULL);
1c2facd1 RW	227
	228	/* Calculate the coverage. */
	229	for (ALL_LIST_ELEMENTS_RO(translator->modules, ln, tmodule)) {
1c2facd1 RW	230	tmodule->coverage = ((double)tmodule->nodes_after_deviations
	231	/ (double)tmodule->nodes_before_deviations)
	232	* 100;
	233	}
	234
	235	/* Load mappings. */
3bb513c3 CH	236	if (lyd_find_xpath(dnode, "./module/mappings", &set) != LY_SUCCESS)
	237	assert(0); /* XXX libyang2: old ly1 code asserted success */
	238	for (size_t i = 0; i < set->count; i++) {
1c2facd1	239	const char xpath_custom, xpath_native;
3bb513c3 CH	240	const struct lysc_node snode_custom, snode_native;
	241
	242	xpath_custom =
	243	yang_dnode_get_string(set->dnodes[i], "./custom");
1c2facd1	244
3bb513c3 CH	245	snode_custom = lys_find_path(translator->ly_ctx, NULL,
3bb513c3 CH	246	xpath_custom, 0);
1c2facd1 RW	247	if (!snode_custom) {
	248	flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
	249	"%s: unknown data path: %s", __func__,
	250	xpath_custom);
3bb513c3	251	ly_set_free(set, NULL);
1c2facd1 RW	252	goto error;
	253	}
	254
3bb513c3 CH	255	xpath_native =
3bb513c3 CH	256	yang_dnode_get_string(set->dnodes[i], "./native");
1c2facd1	257	snode_native =
3bb513c3	258	lys_find_path(ly_native_ctx, NULL, xpath_native, 0);
1c2facd1 RW	259	if (!snode_native) {
	260	flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
	261	"%s: unknown data path: %s", __func__,
	262	xpath_native);
3bb513c3	263	ly_set_free(set, NULL);
1c2facd1 RW	264	goto error;
	265	}
	266
	267	yang_mapping_add(translator, YANG_TRANSLATE_TO_NATIVE,
	268	snode_custom, xpath_custom, xpath_native);
	269	yang_mapping_add(translator, YANG_TRANSLATE_FROM_NATIVE,
	270	snode_native, xpath_native, xpath_custom);
	271	}
3bb513c3	272	ly_set_free(set, NULL);
1c2facd1 RW	273
	274	/* Validate mappings. */
	275	if (yang_translator_validate(translator) != 0)
	276	goto error;
	277
	278	yang_dnode_free(dnode);
	279
	280	return translator;
	281
	282	error:
	283	yang_dnode_free(dnode);
	284	yang_translator_unload(translator);
	285
	286	return NULL;
	287	}
	288
	289	static void yang_tmodule_delete(struct yang_tmodule *tmodule)
	290	{
	291	XFREE(MTYPE_YANG_TRANSLATOR_MODULE, tmodule);
	292	}
	293
	294	void yang_translator_unload(struct yang_translator *translator)
	295	{
	296	for (size_t i = 0; i < YANG_TRANSLATE_MAX; i++)
	297	hash_clean(translator->mappings[i], yang_mapping_hash_free);
	298	translator->modules->del = (void ()(void ))yang_tmodule_delete;
	299	list_delete(&translator->modules);
3bb513c3	300	ly_ctx_destroy(translator->ly_ctx);
1c2facd1 RW	301	RB_REMOVE(yang_translators, &yang_translators, translator);
	302	XFREE(MTYPE_YANG_TRANSLATOR, translator);
	303	}
	304
	305	struct yang_translator yang_translator_find(const char family)
	306	{
	307	struct yang_translator s;
	308
	309	strlcpy(s.family, family, sizeof(s.family));
	310	return RB_FIND(yang_translators, &yang_translators, &s);
	311	}
	312
	313	enum yang_translate_result
	314	yang_translate_xpath(const struct yang_translator *translator, int dir,
	315	char *xpath, size_t xpath_len)
	316	{
	317	struct ly_ctx *ly_ctx;
3bb513c3	318	const struct lysc_node *snode;
1c2facd1 RW	319	struct yang_mapping_node *mapping;
	320	char xpath_canonical[XPATH_MAXLEN];
	321	char keys[4][LIST_MAXKEYLEN];
	322	int n;
	323
	324	if (dir == YANG_TRANSLATE_TO_NATIVE)
	325	ly_ctx = translator->ly_ctx;
	326	else
	327	ly_ctx = ly_native_ctx;
	328
3bb513c3	329	snode = lys_find_path(ly_ctx, NULL, xpath, 0);
1c2facd1 RW	330	if (!snode) {
	331	flog_warn(EC_LIB_YANG_TRANSLATION_ERROR,
	332	"%s: unknown data path: %s", __func__, xpath);
	333	return YANG_TRANSLATE_FAILURE;
	334	}
	335
	336	yang_snode_get_path(snode, YANG_PATH_DATA, xpath_canonical,
	337	sizeof(xpath_canonical));
	338	mapping = yang_mapping_lookup(translator, dir, xpath_canonical);
	339	if (!mapping)
	340	return YANG_TRANSLATE_NOTFOUND;
	341
c84e5187 DL	342	#pragma GCC diagnostic push
	343	#pragma GCC diagnostic ignored "-Wformat-nonliteral"
	344	/* processing format strings from mapping node... */
1c2facd1 RW	345	n = sscanf(xpath, mapping->xpath_from_fmt, keys[0], keys[1], keys[2],
1c2facd1 RW	346	keys[3]);
c84e5187	347	#pragma GCC diagnostic pop
1c2facd1 RW	348	if (n < 0) {
	349	flog_warn(EC_LIB_YANG_TRANSLATION_ERROR,
	350	"%s: sscanf() failed: %s", __func__,
	351	safe_strerror(errno));
	352	return YANG_TRANSLATE_FAILURE;
	353	}
	354
c84e5187 DL	355	#pragma GCC diagnostic push
	356	#pragma GCC diagnostic ignored "-Wformat-nonliteral"
	357	/* processing format strings from mapping node... */
1c2facd1 RW	358	snprintf(xpath, xpath_len, mapping->xpath_to_fmt, keys[0], keys[1],
1c2facd1 RW	359	keys[2], keys[3]);
c84e5187	360	#pragma GCC diagnostic pop
1c2facd1 RW	361
	362	return YANG_TRANSLATE_SUCCESS;
	363	}
	364
	365	int yang_translate_dnode(const struct yang_translator *translator, int dir,
	366	struct lyd_node **dnode)
	367	{
	368	struct ly_ctx *ly_ctx;
	369	struct lyd_node *new;
3bb513c3	370	struct lyd_node root, dnode_iter;
1c2facd1 RW	371
	372	/* Create new libyang data node to hold the translated data. */
	373	if (dir == YANG_TRANSLATE_TO_NATIVE)
	374	ly_ctx = ly_native_ctx;
	375	else
	376	ly_ctx = translator->ly_ctx;
5e02643a	377	new = yang_dnode_new(ly_ctx, false);
1c2facd1 RW	378
1c2facd1 RW	379	/* Iterate over all nodes from the data tree. */
3bb513c3 CH	380	LY_LIST_FOR (*dnode, root) {
3bb513c3 CH	381	LYD_TREE_DFS_BEGIN (root, dnode_iter) {
1c2facd1 RW	382	char xpath[XPATH_MAXLEN];
	383	enum yang_translate_result ret;
	384
	385	yang_dnode_get_path(dnode_iter, xpath, sizeof(xpath));
	386	ret = yang_translate_xpath(translator, dir, xpath,
	387	sizeof(xpath));
	388	switch (ret) {
	389	case YANG_TRANSLATE_SUCCESS:
	390	break;
	391	case YANG_TRANSLATE_NOTFOUND:
	392	goto next;
	393	case YANG_TRANSLATE_FAILURE:
	394	goto error;
	395	}
	396
	397	/* Create new node in the tree of translated data. */
3bb513c3 CH	398	if (lyd_new_path(new, ly_ctx, xpath,
	399	(void *)yang_dnode_get_string(
	400	dnode_iter, NULL),
	401	LYD_NEW_PATH_UPDATE, NULL)) {
1c2facd1 RW	402	flog_err(EC_LIB_LIBYANG,
	403	"%s: lyd_new_path() failed", __func__);
	404	goto error;
	405	}
	406
	407	next:
3bb513c3	408	LYD_TREE_DFS_END(root, dnode_iter);
1c2facd1 RW	409	}
	410	}
	411
	412	/* Replace dnode by the new translated dnode. */
	413	yang_dnode_free(*dnode);
	414	*dnode = new;
	415
	416	return YANG_TRANSLATE_SUCCESS;
	417
	418	error:
	419	yang_dnode_free(new);
	420
	421	return YANG_TRANSLATE_FAILURE;
	422	}
	423
e0ccfad2 RW	424	struct translator_validate_args {
	425	struct yang_translator *translator;
	426	unsigned int errors;
	427	};
	428
3bb513c3	429	static int yang_translator_validate_cb(const struct lysc_node *snode_custom,
e0ccfad2	430	void *arg)
1c2facd1	431	{
e0ccfad2	432	struct translator_validate_args *args = arg;
1c2facd1	433	struct yang_mapping_node *mapping;
3bb513c3 CH	434	const struct lysc_node *snode_native;
3bb513c3 CH	435	const struct lysc_type stype_custom, stype_native;
1c2facd1 RW	436	char xpath[XPATH_MAXLEN];
	437
	438	yang_snode_get_path(snode_custom, YANG_PATH_DATA, xpath, sizeof(xpath));
e0ccfad2 RW	439	mapping = yang_mapping_lookup(args->translator,
e0ccfad2 RW	440	YANG_TRANSLATE_TO_NATIVE, xpath);
1c2facd1 RW	441	if (!mapping) {
	442	flog_warn(EC_LIB_YANG_TRANSLATOR_LOAD,
	443	"%s: missing mapping for \"%s\"", __func__, xpath);
e0ccfad2 RW	444	args->errors += 1;
e0ccfad2 RW	445	return YANG_ITER_CONTINUE;
1c2facd1 RW	446	}
	447
	448	snode_native =
3bb513c3	449	lys_find_path(ly_native_ctx, NULL, mapping->xpath_to_fmt, 0);
1c2facd1 RW	450	assert(snode_native);
	451
	452	/* Check if the YANG types are compatible. */
	453	stype_custom = yang_snode_get_type(snode_custom);
	454	stype_native = yang_snode_get_type(snode_native);
	455	if (stype_custom && stype_native) {
3bb513c3	456	if (stype_custom->basetype != stype_native->basetype) {
1c2facd1 RW	457	flog_warn(
	458	EC_LIB_YANG_TRANSLATOR_LOAD,
	459	"%s: YANG types are incompatible (xpath: \"%s\")",
	460	__func__, xpath);
e0ccfad2 RW	461	args->errors += 1;
e0ccfad2 RW	462	return YANG_ITER_CONTINUE;
1c2facd1 RW	463	}
	464
	465	/* TODO: check if the value spaces are identical. */
	466	}
e0ccfad2 RW	467
e0ccfad2 RW	468	return YANG_ITER_CONTINUE;
1c2facd1 RW	469	}
	470
	471	/*
	472	* Check if the modules from the translator have a mapping for all of their
	473	* schema nodes (after loading the deviations).
	474	*/
	475	static unsigned int yang_translator_validate(struct yang_translator *translator)
	476	{
	477	struct yang_tmodule *tmodule;
	478	struct listnode *ln;
e0ccfad2 RW	479	struct translator_validate_args args;
	480
	481	args.translator = translator;
	482	args.errors = 0;
1c2facd1 RW	483
1c2facd1 RW	484	for (ALL_LIST_ELEMENTS_RO(translator->modules, ln, tmodule)) {
8d869d37 RW	485	yang_snodes_iterate(tmodule->module,
	486	yang_translator_validate_cb,
	487	YANG_ITER_FILTER_NPCONTAINERS
	488	\| YANG_ITER_FILTER_LIST_KEYS
	489	\| YANG_ITER_FILTER_INPUT_OUTPUT,
	490	&args);
1c2facd1 RW	491	}
1c2facd1 RW	492
e0ccfad2	493	if (args.errors)
1c2facd1 RW	494	flog_warn(
	495	EC_LIB_YANG_TRANSLATOR_LOAD,
	496	"%s: failed to validate \"%s\" module translator: %u error(s)",
e0ccfad2	497	__func__, translator->family, args.errors);
1c2facd1	498
e0ccfad2	499	return args.errors;
1c2facd1 RW	500	}
1c2facd1 RW	501
3bb513c3	502	static int yang_module_nodes_count_cb(const struct lysc_node snode, void arg)
1c2facd1	503	{
e0ccfad2	504	unsigned int *total = arg;
1c2facd1 RW	505
1c2facd1 RW	506	*total += 1;
e0ccfad2 RW	507
e0ccfad2 RW	508	return YANG_ITER_CONTINUE;
1c2facd1 RW	509	}
	510
	511	/* Calculate the number of nodes for the given module. */
	512	static unsigned int yang_module_nodes_count(const struct lys_module *module)
	513	{
	514	unsigned int total = 0;
	515
8d869d37 RW	516	yang_snodes_iterate(module, yang_module_nodes_count_cb,
	517	YANG_ITER_FILTER_NPCONTAINERS
	518	\| YANG_ITER_FILTER_LIST_KEYS
	519	\| YANG_ITER_FILTER_INPUT_OUTPUT,
	520	&total);
1c2facd1 RW	521
	522	return total;
	523	}
	524
1c2facd1 RW	525	void yang_translator_init(void)
1c2facd1 RW	526	{
3bb513c3	527	ly_translator_ctx = yang_ctx_new_setup(true, false);
1c2facd1 RW	528	if (!ly_translator_ctx) {
	529	flog_err(EC_LIB_LIBYANG, "%s: ly_ctx_new() failed", __func__);
	530	exit(1);
	531	}
1c2facd1 RW	532
1c2facd1 RW	533	if (!ly_ctx_load_module(ly_translator_ctx, "frr-module-translator",
3bb513c3	534	NULL, NULL)) {
1c2facd1 RW	535	flog_err(
	536	EC_LIB_YANG_MODULE_LOAD,
	537	"%s: failed to load the \"frr-module-translator\" module",
	538	__func__);
	539	exit(1);
	540	}
	541	}
	542
	543	void yang_translator_terminate(void)
	544	{
	545	while (!RB_EMPTY(yang_translators, &yang_translators)) {
	546	struct yang_translator *translator;
	547
	548	translator = RB_ROOT(yang_translators, &yang_translators);
	549	yang_translator_unload(translator);
	550	}
	551
3bb513c3	552	ly_ctx_destroy(ly_translator_ctx);
1c2facd1	553	}