// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2018 NetDEF, Inc. * Renato Westphal */ #ifndef _FRR_YANG_H_ #define _FRR_YANG_H_ #include "memory.h" #include #ifdef HAVE_SYSREPO #include #endif #include "yang_wrappers.h" #ifdef __cplusplus extern "C" { #endif /* Maximum XPath length. */ #define XPATH_MAXLEN 1024 /* Maximum list key length. */ #define LIST_MAXKEYS 8 /* Maximum list key length. */ #define LIST_MAXKEYLEN 128 /* Maximum string length of an YANG value. */ #define YANG_VALUE_MAXLEN 1024 struct yang_module_embed { struct yang_module_embed *next; const char *mod_name, *mod_rev; const char *sub_mod_name; const char *sub_mod_rev; const char *data; LYS_INFORMAT format; }; struct yang_module { RB_ENTRY(yang_module) entry; const char *name; const struct lys_module *info; #ifdef HAVE_CONFD int confd_hash; #endif #ifdef HAVE_SYSREPO sr_subscription_ctx_t *sr_subscription; struct event *sr_thread; #endif }; RB_HEAD(yang_modules, yang_module); RB_PROTOTYPE(yang_modules, yang_module, entry, yang_module_compare); struct yang_data { /* XPath identifier of the data element. */ char xpath[XPATH_MAXLEN]; /* Value encoded as a raw string. */ char *value; }; struct yang_list_keys { /* Number os keys (max: LIST_MAXKEYS). */ uint8_t num; /* Value encoded as a raw string. */ char key[LIST_MAXKEYS][LIST_MAXKEYLEN]; }; enum yang_path_type { YANG_PATH_SCHEMA = 0, YANG_PATH_DATA, }; enum yang_iter_flags { /* Filter non-presence containers. */ YANG_ITER_FILTER_NPCONTAINERS = (1<<0), /* Filter list keys (leafs). */ YANG_ITER_FILTER_LIST_KEYS = (1<<1), /* Filter RPC input/output nodes. */ YANG_ITER_FILTER_INPUT_OUTPUT = (1<<2), }; /* Callback used by the yang_snodes_iterate_*() family of functions. */ typedef int (*yang_iterate_cb)(const struct lysc_node *snode, void *arg); /* Callback used by the yang_dnode_iterate() function. */ typedef int (*yang_dnode_iter_cb)(const struct lyd_node *dnode, void *arg); /* Return values of the 'yang_iterate_cb' callback. */ #define YANG_ITER_CONTINUE 0 #define YANG_ITER_STOP -1 /* Global libyang context for native FRR models. */ extern struct ly_ctx *ly_native_ctx; /* Tree of all loaded YANG modules. */ extern struct yang_modules yang_modules; /* * Create a new YANG module and load it using libyang. If the YANG module is not * found in the YANG_MODELS_PATH directory, the program will exit with an error. * Once loaded, a YANG module can't be unloaded anymore. * * module_name * Name of the YANG module. * * Returns: * Pointer to newly created YANG module. */ extern struct yang_module *yang_module_load(const char *module_name); /* * Load all FRR native YANG models. */ extern void yang_module_load_all(void); /* * Find a YANG module by its name. * * module_name * Name of the YANG module. * * Returns: * Pointer to YANG module if found, NULL otherwise. */ extern struct yang_module *yang_module_find(const char *module_name); /* * Register a YANG module embedded in the binary file. Should be called * from a constructor function. * * embed * YANG module embedding structure to register. (static global provided * by caller.) */ extern void yang_module_embed(struct yang_module_embed *embed); /* * Iterate recursively over all children of a schema node. * * snode * YANG schema node to operate on. * * module * When set, iterate over all nodes of the specified module only. * * cb * Function to call with each schema node. * * flags * YANG_ITER_* flags to control how the iteration is performed. * * arg * Arbitrary argument passed as the second parameter in each call to 'cb'. * * Returns: * The return value of the last called callback. */ extern int yang_snodes_iterate_subtree(const struct lysc_node *snode, const struct lys_module *module, yang_iterate_cb cb, uint16_t flags, void *arg); /* * Iterate over all libyang schema nodes from all loaded modules of the * given YANG module. * * module * When set, iterate over all nodes of the specified module only. * * cb * Function to call with each schema node. * * flags * YANG_ITER_* flags to control how the iteration is performed. * * arg * Arbitrary argument passed as the second parameter in each call to 'cb'. * * Returns: * The return value of the last called callback. */ extern int yang_snodes_iterate(const struct lys_module *module, yang_iterate_cb cb, uint16_t flags, void *arg); /* * Build schema path or data path of the schema node. * * snode * libyang schema node to be processed. * * type * Specify whether a schema path or a data path should be built. * * xpath * Pointer to previously allocated buffer. * * xpath_len * Size of the xpath buffer. */ extern void yang_snode_get_path(const struct lysc_node *snode, enum yang_path_type type, char *xpath, size_t xpath_len); /* * Find libyang schema node for the given xpath. Uses `lys_find_xpath`, * returning only the first of a set of nodes -- normally there should only * be one. * * ly_ctx * libyang context to operate on. * * xpath * XPath expression (absolute or relative) to find the schema node for. * * options * Libyang findxpathoptions value (see lys_find_xpath). * * Returns: * The libyang schema node if found, or NULL if not found. */ extern struct lysc_node *yang_find_snode(struct ly_ctx *ly_ctx, const char *xpath, uint32_t options); /* * Find first parent schema node which is a presence-container or a list * (non-presence containers are ignored). * * snode * libyang schema node to operate on. * * Returns: * The parent libyang schema node if found, or NULL if not found. */ extern struct lysc_node *yang_snode_real_parent(const struct lysc_node *snode); /* * Find first parent schema node which is a list. * * snode * libyang schema node to operate on. * * Returns: * The parent libyang schema node (list) if found, or NULL if not found. */ extern struct lysc_node *yang_snode_parent_list(const struct lysc_node *snode); /* * Check if the libyang schema node represents typeless data (e.g. containers, * leafs of type empty, etc). * * snode * libyang schema node to operate on. * * Returns: * true if the schema node represents typeless data, false otherwise. */ extern bool yang_snode_is_typeless_data(const struct lysc_node *snode); /* * Get the default value associated to a YANG leaf or leaf-list. * * snode * libyang schema node to operate on. * * Returns: * The default value if it exists, NULL otherwise. */ extern const char *yang_snode_get_default(const struct lysc_node *snode); /* * Get the type structure of a leaf of leaf-list. If the type is a leafref, the * final (if there is a chain of leafrefs) target's type is found. * * snode * libyang schema node to operate on. * * Returns: * The found type if the schema node represents a leaf or a leaf-list, NULL * otherwise. */ extern const struct lysc_type * yang_snode_get_type(const struct lysc_node *snode); /* * Get the number of key nodes for the given list. * * snode * libyang (LYS_LIST) schema node to operate on. * * Returns: * The number of key LYS_LEAFs as children of this list node. */ extern unsigned int yang_snode_num_keys(const struct lysc_node *snode); #define LY_FOR_KEYS(snode, skey) \ for ((skey) = (const struct lysc_node_leaf *)lysc_node_child((snode)); \ (skey); (skey) = (const struct lysc_node_leaf *)((skey)->next)) \ if (!lysc_is_key(skey)) { \ break; \ } else /* * Build data path of the data node. * * dnode * libyang data node to be processed. * * xpath * Pointer to previously allocated buffer. * * xpath_len * Size of the xpath buffer. */ extern void yang_dnode_get_path(const struct lyd_node *dnode, char *xpath, size_t xpath_len); /* * Return the schema name of the given libyang data node. * * dnode * libyang data node. * * xpath_fmt * Optional XPath expression (absolute or relative) to specify a different * data node to operate on in the same data tree. * * Returns: * Schema name of the libyang data node. */ extern const char *yang_dnode_get_schema_name(const struct lyd_node *dnode, const char *xpath_fmt, ...) PRINTFRR(2, 3); /* * Find a libyang data node by its YANG data path. * * dnode * Base libyang data node to operate on. * * xpath * Limited XPath (absolute or relative) string. See Path in libyang * documentation for restrictions. * * Returns: * The libyang data node if found, or NULL if not found. */ extern struct lyd_node *yang_dnode_get(const struct lyd_node *dnode, const char *xpath); /* * Find a libyang data node by its YANG data path. * * dnode * Base libyang data node to operate on. * * xpath_fmt * Limited XPath (absolute or relative) format string. See Path in libyang * documentation for restrictions. * * ... * any parameters for xpath_fmt. * * Returns: * The libyang data node if found, or NULL if not found. */ extern struct lyd_node *yang_dnode_getf(const struct lyd_node *dnode, const char *path_fmt, ...) PRINTFRR(2, 3); /* * Check if a libyang data node exists. * * dnode * Base libyang data node to operate on. * * xpath * Limited XPath (absolute or relative) string. See Path in libyang * documentation for restrictions. * * Returns: * true if a libyang data node was found, false otherwise. */ extern bool yang_dnode_exists(const struct lyd_node *dnode, const char *xpath); /* * Check if a libyang data node exists. * * dnode * Base libyang data node to operate on. * * xpath_fmt * Limited XPath (absolute or relative) format string. See Path in * libyang documentation for restrictions. * * ... * any parameters for xpath_fmt. * * Returns: * true if a libyang data node was found, false otherwise. */ extern bool yang_dnode_existsf(const struct lyd_node *dnode, const char *xpath_fmt, ...) PRINTFRR(2, 3); /* * Iterate over all libyang data nodes that satisfy an XPath query. * * cb * Function to call with each data node. * * arg * Arbitrary argument passed as the second parameter in each call to 'cb'. * * dnode * Base libyang data node to operate on. * * xpath_fmt * XPath expression (absolute or relative). * * ... * any parameters for xpath_fmt. */ void yang_dnode_iterate(yang_dnode_iter_cb cb, void *arg, const struct lyd_node *dnode, const char *xpath_fmt, ...) PRINTFRR(4, 5); /* * Check if the libyang data node contains a default value. Non-presence * containers are assumed to always contain a default value. * * dnode * Base libyang data node to operate on. * * xpath * Optional XPath expression (absolute or relative) to specify a different * data node to operate on in the same data tree. * * Returns: * true if the data node contains the default value, false otherwise. */ extern bool yang_dnode_is_default(const struct lyd_node *dnode, const char *xpath); /* * Check if the libyang data node contains a default value. Non-presence * containers are assumed to always contain a default value. * * dnode * Base libyang data node to operate on. * * xpath * Optional limited XPath (absolute or relative) format string. See Path in * libyang documentation for restrictions. * * ... * any parameters for xpath_fmt. * * Returns: * true if the data node contains the default value, false otherwise. */ extern bool yang_dnode_is_defaultf(const struct lyd_node *dnode, const char *xpath_fmt, ...) PRINTFRR(2, 3); /* * Check if the libyang data node and all of its children contain default * values. Non-presence containers are assumed to always contain a default * value. * * dnode * libyang data node to operate on. * * Returns: * true if the data node and all of its children contain default values, * false otherwise. */ extern bool yang_dnode_is_default_recursive(const struct lyd_node *dnode); /* * Change the value of a libyang leaf node. * * dnode * libyang data node to operate on. * * value * String representing the new value. */ extern void yang_dnode_change_leaf(struct lyd_node *dnode, const char *value); /* * Create a new libyang data node. * * ly_ctx * libyang context to operate on. * * config * Specify whether the data node will contain only configuration data (true) * or both configuration data and state data (false). * * Returns: * Pointer to newly created libyang data node. */ extern struct lyd_node *yang_dnode_new(struct ly_ctx *ly_ctx, bool config_only); /* * Duplicate a libyang data node. * * dnode * libyang data node to duplicate. * * Returns: * Pointer to duplicated libyang data node. */ extern struct lyd_node *yang_dnode_dup(const struct lyd_node *dnode); /* * Delete a libyang data node. * * dnode * Pointer to the libyang data node that is going to be deleted along with * the entire tree it belongs to. */ extern void yang_dnode_free(struct lyd_node *dnode); /* * Create a new yang_data structure. * * xpath * Data path of the YANG data. * * value * String representing the value of the YANG data. * * Returns: * Pointer to newly created yang_data structure. */ extern struct yang_data *yang_data_new(const char *xpath, const char *value); /* * Delete a yang_data structure. * * data * yang_data to delete. */ extern void yang_data_free(struct yang_data *data); /* * Create a new linked list of yang_data structures. The list 'del' callback is * initialized appropriately so that the entire list can be deleted safely with * list_delete_and_null(). * * Returns: * Pointer to newly created linked list. */ extern struct list *yang_data_list_new(void); /* * Find the yang_data structure corresponding to an XPath in a list. * * list * list of yang_data structures to operate on. * * xpath_fmt * XPath to search for (format string). * * Returns: * Pointer to yang_data if found, NULL otherwise. */ extern struct yang_data *yang_data_list_find(const struct list *list, const char *xpath_fmt, ...) PRINTFRR(2, 3); /* * Create and set up a libyang context (for use by the translator) * * embedded_modules * Specify whether libyang should attempt to look for embedded YANG modules. * * explicit_compile * True if the caller will later call ly_ctx_compile to compile all loaded * modules at once. */ extern struct ly_ctx *yang_ctx_new_setup(bool embedded_modules, bool explicit_compile); /* * Enable or disable libyang verbose debugging. * * enable * When set to true, enable libyang verbose debugging, otherwise disable it. */ extern void yang_debugging_set(bool enable); /* * Print libyang error messages into the provided buffer. * * ly_ctx * libyang context to operate on. * * buf * Buffer to store the libyang error messages. * * buf_len * Size of buf. * * Returns: * The provided buffer. */ extern const char *yang_print_errors(struct ly_ctx *ly_ctx, char *buf, size_t buf_len); /* * Initialize the YANG subsystem. Should be called only once during the * daemon initialization process. * * embedded_modules * Specify whether libyang should attempt to look for embedded YANG modules. * defer_compile * Hold off on compiling modules until yang_init_loading_complete is called. */ extern void yang_init(bool embedded_modules, bool defer_compile); /* * Should be called after yang_init and all yang_module_load()s have been done, * compiles all modules loaded into the yang context. */ extern void yang_init_loading_complete(void); /* * Finish the YANG subsystem gracefully. Should be called only when the daemon * is exiting. */ extern void yang_terminate(void); /* * API to return the parent dnode having a given schema-node name * Use case: One has to access the parent dnode's private pointer * for a given child node. * For that there is a need to find parent dnode first. * * dnode The starting node to work on * * name The name of container/list schema-node * * Returns The dnode matched with the given name */ extern const struct lyd_node * yang_dnode_get_parent(const struct lyd_node *dnode, const char *name); /* * In some cases there is a need to auto delete the parent nodes * if the given node is last in the list. * It tries to delete all the parents in a given tree in a given module. * The use case is with static routes and route maps * example : ip route 1.1.1.1/32 ens33 * ip route 1.1.1.1/32 ens34 * After this no ip route 1.1.1.1/32 ens34 came, now staticd * has to find out upto which level it has to delete the dnodes. * For this case it has to send delete nexthop * After this no ip route 1.1.1.1/32 ens33 came, now staticd has to * clear nexthop, path and route nodes. * The same scheme is required for routemaps also * dnode The starting node to work on * * Returns The final parent node selected for deletion */ extern const struct lyd_node * yang_get_subtree_with_no_sibling(const struct lyd_node *dnode); /* To get the relative position of a node in list */ extern uint32_t yang_get_list_pos(const struct lyd_node *node); /* To get the number of elements in a list * * dnode : The head of list * Returns : The number of dnodes present in the list */ extern uint32_t yang_get_list_elements_count(const struct lyd_node *node); /* API to check if the given node is last node in the list */ bool yang_is_last_list_dnode(const struct lyd_node *dnode); /* API to check if the given node is last node in the data tree level */ bool yang_is_last_level_dnode(const struct lyd_node *dnode); #ifdef __cplusplus } #endif #endif /* _FRR_YANG_H_ */