blob: 30c358c2d636674fa07f732329be06dc39eaef1b [file] [log] [blame]
/**
* @file parser_xml.c
* @author Radek Krejci <rkrejci@cesnet.cz>
* @brief XML data parser for libyang
*
* Copyright (c) 2019 CESNET, z.s.p.o.
*
* This source code is licensed under BSD 3-Clause License (the "License").
* You may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://opensource.org/licenses/BSD-3-Clause
*/
#include "common.h"
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "context.h"
#include "dict.h"
#include "log.h"
#include "plugins_types.h"
#include "set.h"
#include "tree_data.h"
#include "tree_data_internal.h"
#include "tree_schema.h"
#include "xml.h"
#include "validation.h"
/**
* @brief internal context for XML YANG data parser.
*
* The leading part is compatible with the struct lyxml_context
*/
struct lyd_xml_ctx {
struct ly_ctx *ctx; /**< libyang context */
uint64_t line; /**< number of the line being currently processed */
enum LYXML_PARSER_STATUS status; /**< status providing information about the next expected object in input data */
struct ly_set elements; /**< list of not-yet-closed elements */
struct ly_set ns; /**< handled with LY_SET_OPT_USEASLIST */
uint16_t options; /**< various @ref dataparseroptions. */
uint16_t path_len; /**< used bytes in the path buffer */
#define LYD_PARSER_BUFSIZE 4078
char path[LYD_PARSER_BUFSIZE]; /**< buffer for the generated path */
struct ly_set incomplete_type_validation; /**< set of nodes validated with LY_EINCOMPLETE result */
struct ly_set incomplete_type_validation_attrs; /**< set of attributes validated with LY_EINCOMPLETE result */
struct ly_set when_check; /**< set of nodes with "when" conditions */
};
/**
* @brief XML-parser's implementation of ly_type_resolve_prefix() callback to provide mapping between prefixes used in the values to the schema
* via XML namespaces.
*/
static const struct lys_module *
lydxml_resolve_prefix(struct ly_ctx *ctx, const char *prefix, size_t prefix_len, void *parser)
{
const struct lyxml_ns *ns;
struct lyxml_context *xmlctx = (struct lyxml_context*)parser;
ns = lyxml_ns_get(xmlctx, prefix, prefix_len);
if (!ns) {
return NULL;
}
return ly_ctx_get_module_implemented_ns(ctx, ns->uri);
}
struct attr_data_s {
const char *prefix;
const char *name;
char *value;
size_t prefix_len;
size_t name_len;
size_t value_len;
int dynamic;
};
/**
* @brief Parse XML attributes of the XML element of YANG data.
*
* @param[in] ctx XML YANG data parser context.
* @param[in,out] data Pointer to the XML string representation of the YANG data to parse.
* @param[out] attributes Resulting list of the parsed attributes. XML namespace definitions are not parsed
* as attributes, they are stored internally in the parser context.
* @reutn LY_ERR value.
*/
static LY_ERR
lydxml_attributes_parse(struct lyd_xml_ctx *ctx, const char **data, struct ly_set *attrs_data)
{
LY_ERR ret = LY_SUCCESS;
unsigned int u;
const char *prefix, *name;
size_t prefix_len, name_len;
struct attr_data_s *attr_data;
while(ctx->status == LYXML_ATTRIBUTE &&
lyxml_get_attribute((struct lyxml_context*)ctx, data, &prefix, &prefix_len, &name, &name_len) == LY_SUCCESS) {
char *buffer = NULL;
size_t buffer_size = 0;
if (!name) {
/* seems like all the attrributes were internally processed as namespace definitions */
continue;
}
/* auxiliary store the prefix information and value string, because we have to wait with resolving prefix
* to the time when all the namespaces, defined in this element, are parsed. With the prefix we can find the
* annotation definition for the attribute and correctly process the value */
attr_data = malloc(sizeof *attr_data);
attr_data->prefix = prefix;
attr_data->name = name;
attr_data->prefix_len = prefix_len;
attr_data->name_len = name_len;
ret = lyxml_get_string((struct lyxml_context *)ctx, data, &buffer, &buffer_size, &attr_data->value, &attr_data->value_len, &attr_data->dynamic);
LY_CHECK_ERR_GOTO(ret, free(attr_data), error);
ly_set_add(attrs_data, attr_data, LY_SET_OPT_USEASLIST);
}
return LY_SUCCESS;
error:
for (u = 0; u < attrs_data->count; ++u) {
if (((struct attr_data_s*)attrs_data->objs[u])->dynamic) {
free(((struct attr_data_s*)attrs_data->objs[u])->value);
}
}
ly_set_erase(attrs_data, free);
return ret;
}
static LY_ERR
lydxml_attributes(struct lyd_xml_ctx *ctx, struct ly_set *attrs_data, const struct lysc_node *sparent, struct lyd_attr **attr)
{
LY_ERR ret = LY_EVALID, rc;
const struct lyxml_ns *ns;
struct lys_module *mod;
for (unsigned int u = 0; u < attrs_data->count; ++u) {
struct attr_data_s *attr_data = (struct attr_data_s*)attrs_data->objs[u];
if (!attr_data->prefix_len) {
/* in XML, all attributes must be prefixed
* TODO exception for NETCONF filters which are supposed to map to the ietf-netconf without prefix */
if (ctx->options & LYD_OPT_STRICT) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_REFERENCE, "Missing mandatory prefix for XML attribute \"%.*s\".",
attr_data->name_len, attr_data->name);
}
skip_attr:
if (attr_data->dynamic) {
free(attr_data->value);
attr_data->dynamic = 0;
}
continue;
}
/* get namespace of the attribute to find its annotation definition */
ns = lyxml_ns_get((struct lyxml_context *)ctx, attr_data->prefix, attr_data->prefix_len);
if (!ns) {
/* unknown namespace, ignore the attribute */
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_REFERENCE, "Unknown XML prefix \"%.*s\".", attr_data->prefix_len, attr_data->prefix);
goto cleanup;
}
mod = ly_ctx_get_module_implemented_ns(ctx->ctx, ns->uri);
if (!mod) {
/* module is not implemented or not present in the schema */
if (ctx->options & LYD_OPT_STRICT) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_REFERENCE,
"Unknown (or not implemented) YANG module with namespace \"%s\" for attribute \"%.*s%s%.*s\".",
ns, attr_data->prefix_len, attr_data->prefix, attr_data->prefix_len ? ":" : "", attr_data->name_len,
attr_data->name);
}
goto skip_attr;
}
rc = lyd_create_attr(NULL, attr, mod, attr_data->name, attr_data->name_len, attr_data->value,
attr_data->value_len, &attr_data->dynamic, lydxml_resolve_prefix, ctx, LYD_XML, sparent);
if (rc == LY_EINCOMPLETE) {
ly_set_add(&ctx->incomplete_type_validation_attrs, attr, LY_SET_OPT_USEASLIST);
} else if (rc) {
ret = rc;
goto cleanup;
}
}
ret = LY_SUCCESS;
cleanup:
for (unsigned int u = 0; u < attrs_data->count; ++u) {
if (((struct attr_data_s*)attrs_data->objs[u])->dynamic) {
free(((struct attr_data_s*)attrs_data->objs[u])->value);
}
}
ly_set_erase(attrs_data, free);
return ret;
}
/**
* @brief Parse XML elements as children YANG data node of the specified parent node.
*
* @param[in] ctx XML YANG data parser context.
* @param[in] parent Parent node where the children are inserted. NULL in case of parsing top-level elements.
* @param[in,out] data Pointer to the XML string representation of the YANG data to parse.
* @param[out] node Resulting list of the parsed nodes.
* @return LY_ERR value.
*/
static LY_ERR
lydxml_nodes(struct lyd_xml_ctx *ctx, struct lyd_node_inner *parent, const char **data, struct lyd_node **first)
{
LY_ERR ret = LY_SUCCESS;
const char *prefix, *name;
size_t prefix_len, name_len;
struct ly_set attrs_data = {0};
const struct lyxml_ns *ns;
struct lyd_attr *attr = NULL, *attr2;
const struct lysc_node *snode;
struct lys_module *mod;
unsigned int parents_count = ctx->elements.count;
struct lyd_node *cur = NULL, *key_anchor;
int dynamic = 0;
char *buffer = NULL, *value;
size_t buffer_size = 0, value_len;
while (ctx->status == LYXML_ELEMENT) {
ret = lyxml_get_element((struct lyxml_context *)ctx, data, &prefix, &prefix_len, &name, &name_len);
LY_CHECK_GOTO(ret, cleanup);
if (!name) {
/* closing previous element */
if (ctx->elements.count < parents_count) {
/* all siblings parsed */
break;
} else {
continue;
}
}
if (ctx->status == LYXML_ATTRIBUTE) {
/* first parse all attributes so we have all the namespaces available */
if (lydxml_attributes_parse(ctx, data, &attrs_data) != LY_SUCCESS) {
ret = LY_EVALID;
goto cleanup;
}
}
ns = lyxml_ns_get((struct lyxml_context *)ctx, prefix, prefix_len);
if (!ns) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_REFERENCE, "Unknown XML prefix \"%.*s\".", prefix_len, prefix);
ret = LY_EVALID;
goto cleanup;
}
mod = ly_ctx_get_module_implemented_ns(ctx->ctx, ns->uri);
if (!mod) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_REFERENCE, "No module with namespace \"%s\" in the context.", ns->uri);
ret = LY_EVALID;
goto cleanup;
}
snode = lys_find_child(parent ? parent->schema : NULL, mod, name, name_len, 0, 0);
if (!snode) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_REFERENCE, "Element \"%.*s\" not found in the \"%s\" module.",
name_len, name, mod->name);
ret = LY_EVALID;
goto cleanup;
}
/* create actual attributes so that prefixes are available in the context */
if (attrs_data.count) {
LY_CHECK_GOTO(ret = lydxml_attributes(ctx, &attrs_data, snode, &attr), cleanup);
}
if (snode->nodetype & (LYS_ACTION | LYS_NOTIF)) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_DATA, "Unexpected %s element \"%.*s\".",
snode->nodetype == LYS_ACTION ? "RPC/action" : "notification", name_len, name);
ret = LY_EVALID;
goto cleanup;
}
if (snode->nodetype & LYD_NODE_TERM) {
if (ctx->status == LYXML_ELEM_CONTENT) {
/* get the value */
ret = lyxml_get_string((struct lyxml_context *)ctx, data, &buffer, &buffer_size, &value, &value_len, &dynamic);
if (ret != LY_SUCCESS) {
if (ret == LY_EINVAL) {
/* just indentation of a child element found */
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_SYNTAX, "Child element inside terminal node \"%s\" found.",
snode->name);
}
goto cleanup;
}
} else {
/* no content - validate empty value */
value = "";
value_len = 0;
dynamic = 0;
}
/* create node */
ret = lyd_create_term(snode, value, value_len, &dynamic, lydxml_resolve_prefix, ctx, LYD_XML, &cur);
/* buffer spent */
buffer = NULL;
if (ret == LY_EINCOMPLETE) {
if (!(ctx->options & LYD_OPT_PARSE_ONLY)) {
ly_set_add(&ctx->incomplete_type_validation, cur, LY_SET_OPT_USEASLIST);
}
} else if (ret) {
goto cleanup;
}
if (parent && (cur->schema->flags & LYS_KEY)) {
/* check the key order, the anchor must always be the last child */
key_anchor = lyd_get_prev_key_anchor(parent->child, cur->schema);
if ((!key_anchor && parent->child) || (key_anchor && key_anchor->next)) {
if (ctx->options & LYD_OPT_STRICT) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_DATA, "Invalid position of the key \"%s\" in a list.",
cur->schema->name);
ret = LY_EVALID;
goto cleanup;
} else {
LOGWRN(ctx->ctx, "Invalid position of the key \"%s\" in a list.", cur->schema->name);
}
}
}
} else if (snode->nodetype & LYD_NODE_INNER) {
if (ctx->status == LYXML_ELEM_CONTENT) {
LY_ERR r = lyxml_get_string((struct lyxml_context *)ctx, data, &buffer, &buffer_size, &value, &value_len, &dynamic);
if (r != LY_EINVAL && (r != LY_SUCCESS || value_len != 0)) {
LOGINT(ctx->ctx);
ret = LY_EINT;
goto cleanup;
}
}
/* create node */
ret = lyd_create_inner(snode, &cur);
LY_CHECK_GOTO(ret, cleanup);
/* process children */
if (ctx->status == LYXML_ELEMENT && parents_count != ctx->elements.count) {
ret = lydxml_nodes(ctx, (struct lyd_node_inner *)cur, data, lyd_node_children_p(cur));
LY_CHECK_GOTO(ret, cleanup);
}
if (!(ctx->options & LYD_OPT_PARSE_ONLY)) {
/* new node validation, autodelete CANNOT occur, all nodes are new */
ret = lyd_validate_new(lyd_node_children_p(cur), snode, NULL);
LY_CHECK_GOTO(ret, cleanup);
/* add any missing default children */
ret = lyd_validate_defaults_r((struct lyd_node_inner *)cur, lyd_node_children_p(cur), NULL, NULL,
&ctx->incomplete_type_validation, &ctx->when_check);
LY_CHECK_GOTO(ret, cleanup);
}
/* hash now that all keys should be parsed, rehash for key-less list */
if (snode->nodetype == LYS_LIST) {
lyd_hash(cur);
}
} else if (snode->nodetype & LYD_NODE_ANY) {
unsigned int cur_element_index = ctx->elements.count;
const char *start = *data, *stop;
const char *p, *n;
size_t p_len, n_len;
/* skip children data and store them as a string */
while (ctx->status != LYXML_END && cur_element_index <= ctx->elements.count) {
switch (ctx->status) {
case LYXML_ELEMENT:
ret = lyxml_get_element((struct lyxml_context *)ctx, data, &p, &p_len, &n, &n_len);
LY_CHECK_GOTO(ret, cleanup);
break;
case LYXML_ATTRIBUTE:
lyxml_get_attribute((struct lyxml_context *)ctx, data, &p, &p_len, &n, &n_len);
break;
case LYXML_ELEM_CONTENT:
case LYXML_ATTR_CONTENT:
ret = lyxml_get_string((struct lyxml_context *)ctx, data, NULL, NULL, NULL, NULL, NULL);
/* not an error, just incorrect XML parser status */
if (ret && (ret != LY_EINVAL)) {
goto cleanup;
}
break;
case LYXML_END:
/* end of data */
LOGINT(ctx->ctx);
ret = LY_EINT;
goto cleanup;
}
}
/* get value */
if (start != *data) {
/* data now points after the anydata's closing element tag, we need just end of its content */
for (stop = *data - 1; *stop != '<'; --stop);
start = lydict_insert(ctx->ctx, start, stop - start);
} else {
start = NULL;
}
/* create node */
ret = lyd_create_any(snode, start, LYD_ANYDATA_XML, &cur);
if (ret) {
lydict_remove(ctx->ctx, start);
goto cleanup;
}
}
/* correct flags */
if (!(snode->nodetype & (LYS_ACTION | LYS_NOTIF)) && snode->when) {
if (ctx->options & LYD_OPT_TRUSTED) {
/* just set it to true */
cur->flags |= LYD_WHEN_TRUE;
} else {
/* remember we need to evaluate this node's when */
ly_set_add(&ctx->when_check, cur, LY_SET_OPT_USEASLIST);
}
}
if (ctx->options & LYD_OPT_TRUSTED) {
/* node is valid */
cur->flags &= ~LYD_NEW;
}
LY_LIST_FOR(attr, attr2) {
if (!strcmp(attr2->name, "default") && !strcmp(attr2->annotation->module->name, "ietf-netconf-with-defaults")
&& attr2->value.boolean) {
/* node is default according to the metadata */
cur->flags |= LYD_DEFAULT;
}
}
/* add attributes */
assert(!cur->attr);
cur->attr = attr;
attr = NULL;
/* insert */
lyd_insert_node((struct lyd_node *)parent, first, cur);
cur = NULL;
}
/* success */
ret = LY_SUCCESS;
cleanup:
free(buffer);
lyd_free_attr(ctx->ctx, attr, 1);
lyd_free_tree(cur);
for (unsigned int u = 0; u < attrs_data.count; ++u) {
if (((struct attr_data_s*)attrs_data.objs[u])->dynamic) {
free(((struct attr_data_s*)attrs_data.objs[u])->value);
}
}
ly_set_erase(&attrs_data, free);
if (ret && *first) {
lyd_free_siblings(*first);
*first = NULL;
}
return ret;
}
LY_ERR
lyd_parse_xml(struct ly_ctx *ctx, const char *data, int options, struct lyd_node **tree)
{
LY_ERR ret = LY_SUCCESS;
struct lyd_xml_ctx xmlctx = {0};
uint32_t i = 0;
const struct lys_module *mod;
struct lyd_node *first, *next, **first2;
xmlctx.options = options;
xmlctx.ctx = ctx;
xmlctx.line = 1;
/* init */
*tree = NULL;
/* parse XML data */
ret = lydxml_nodes(&xmlctx, NULL, &data, tree);
LY_CHECK_GOTO(ret, cleanup);
if (!(options & LYD_OPT_PARSE_ONLY)) {
next = *tree;
while (1) {
if (options & LYD_VALOPT_DATA_ONLY) {
mod = lyd_data_next_module(&next, &first);
} else {
mod = lyd_mod_next_module(next, NULL, 0, ctx, &i, &first);
}
if (!mod) {
break;
}
if (first == *tree) {
/* make sure first2 changes are carried to tree */
first2 = tree;
} else {
first2 = &first;
}
/* validate new top-level nodes, autodelete CANNOT occur, all nodes are new */
ret = lyd_validate_new(first2, NULL, mod);
LY_CHECK_GOTO(ret, cleanup);
/* add all top-level defaults for this module */
ret = lyd_validate_defaults_r(NULL, first2, NULL, mod, &xmlctx.incomplete_type_validation, &xmlctx.when_check);
LY_CHECK_GOTO(ret, cleanup);
/* finish incompletely validated terminal values/attributes and when conditions */
ret = lyd_validate_unres(tree, &xmlctx.when_check, &xmlctx.incomplete_type_validation,
&xmlctx.incomplete_type_validation_attrs, LYD_XML, lydxml_resolve_prefix, ctx);
LY_CHECK_GOTO(ret, cleanup);
/* perform final validation that assumes the data tree is final */
ret = lyd_validate_siblings_r(*first2, NULL, mod, options);
LY_CHECK_GOTO(ret, cleanup);
}
}
cleanup:
/* there should be no unresolved types stored */
assert(!(options & LYD_OPT_PARSE_ONLY) || (!xmlctx.incomplete_type_validation.count
&& !xmlctx.incomplete_type_validation_attrs.count && !xmlctx.when_check.count));
ly_set_erase(&xmlctx.incomplete_type_validation, NULL);
ly_set_erase(&xmlctx.incomplete_type_validation_attrs, NULL);
ly_set_erase(&xmlctx.when_check, NULL);
lyxml_context_clear((struct lyxml_context *)&xmlctx);
if (ret) {
lyd_free_all(*tree);
*tree = NULL;
}
return ret;
}