openwrt/package/libnl-tiny/src/genl_ctrl.c

303 lines
6.8 KiB
C

/*
* lib/genl/ctrl.c Generic Netlink Controller
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation version 2.1
* of the License.
*
* Copyright (c) 2003-2008 Thomas Graf <tgraf@suug.ch>
*/
/**
* @ingroup genl_mngt
* @defgroup ctrl Controller
* @brief
*
* @{
*/
#include <netlink-generic.h>
#include <netlink/netlink.h>
#include <netlink/genl/genl.h>
#include <netlink/genl/family.h>
#include <netlink/genl/mngt.h>
#include <netlink/genl/ctrl.h>
#include <netlink/utils.h>
/** @cond SKIP */
#define CTRL_VERSION 0x0001
static struct nl_cache_ops genl_ctrl_ops;
/** @endcond */
static int ctrl_request_update(struct nl_cache *c, struct nl_sock *h)
{
return genl_send_simple(h, GENL_ID_CTRL, CTRL_CMD_GETFAMILY,
CTRL_VERSION, NLM_F_DUMP);
}
static struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = {
[CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 },
[CTRL_ATTR_FAMILY_NAME] = { .type = NLA_STRING,
.maxlen = GENL_NAMSIZ },
[CTRL_ATTR_VERSION] = { .type = NLA_U32 },
[CTRL_ATTR_HDRSIZE] = { .type = NLA_U32 },
[CTRL_ATTR_MAXATTR] = { .type = NLA_U32 },
[CTRL_ATTR_OPS] = { .type = NLA_NESTED },
};
static struct nla_policy family_op_policy[CTRL_ATTR_OP_MAX+1] = {
[CTRL_ATTR_OP_ID] = { .type = NLA_U32 },
[CTRL_ATTR_OP_FLAGS] = { .type = NLA_U32 },
};
static int ctrl_msg_parser(struct nl_cache_ops *ops, struct genl_cmd *cmd,
struct genl_info *info, void *arg)
{
struct genl_family *family;
struct nl_parser_param *pp = arg;
int err;
family = genl_family_alloc();
if (family == NULL) {
err = -NLE_NOMEM;
goto errout;
}
if (info->attrs[CTRL_ATTR_FAMILY_NAME] == NULL) {
err = -NLE_MISSING_ATTR;
goto errout;
}
if (info->attrs[CTRL_ATTR_FAMILY_ID] == NULL) {
err = -NLE_MISSING_ATTR;
goto errout;
}
family->ce_msgtype = info->nlh->nlmsg_type;
genl_family_set_id(family,
nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]));
genl_family_set_name(family,
nla_get_string(info->attrs[CTRL_ATTR_FAMILY_NAME]));
if (info->attrs[CTRL_ATTR_VERSION]) {
uint32_t version = nla_get_u32(info->attrs[CTRL_ATTR_VERSION]);
genl_family_set_version(family, version);
}
if (info->attrs[CTRL_ATTR_HDRSIZE]) {
uint32_t hdrsize = nla_get_u32(info->attrs[CTRL_ATTR_HDRSIZE]);
genl_family_set_hdrsize(family, hdrsize);
}
if (info->attrs[CTRL_ATTR_MAXATTR]) {
uint32_t maxattr = nla_get_u32(info->attrs[CTRL_ATTR_MAXATTR]);
genl_family_set_maxattr(family, maxattr);
}
if (info->attrs[CTRL_ATTR_OPS]) {
struct nlattr *nla, *nla_ops;
int remaining;
nla_ops = info->attrs[CTRL_ATTR_OPS];
nla_for_each_nested(nla, nla_ops, remaining) {
struct nlattr *tb[CTRL_ATTR_OP_MAX+1];
int flags = 0, id;
err = nla_parse_nested(tb, CTRL_ATTR_OP_MAX, nla,
family_op_policy);
if (err < 0)
goto errout;
if (tb[CTRL_ATTR_OP_ID] == NULL) {
err = -NLE_MISSING_ATTR;
goto errout;
}
id = nla_get_u32(tb[CTRL_ATTR_OP_ID]);
if (tb[CTRL_ATTR_OP_FLAGS])
flags = nla_get_u32(tb[CTRL_ATTR_OP_FLAGS]);
err = genl_family_add_op(family, id, flags);
if (err < 0)
goto errout;
}
}
err = pp->pp_cb((struct nl_object *) family, pp);
errout:
genl_family_put(family);
return err;
}
/**
* @name Cache Management
* @{
*/
int genl_ctrl_alloc_cache(struct nl_sock *sock, struct nl_cache **result)
{
return nl_cache_alloc_and_fill(&genl_ctrl_ops, sock, result);
}
/**
* Look up generic netlink family by id in the provided cache.
* @arg cache Generic netlink family cache.
* @arg id Family identifier.
*
* Searches through the cache looking for a registered family
* matching the specified identifier. The caller will own a
* reference on the returned object which needs to be given
* back after usage using genl_family_put().
*
* @return Generic netlink family object or NULL if no match was found.
*/
struct genl_family *genl_ctrl_search(struct nl_cache *cache, int id)
{
struct genl_family *fam;
if (cache->c_ops != &genl_ctrl_ops)
BUG();
nl_list_for_each_entry(fam, &cache->c_items, ce_list) {
if (fam->gf_id == id) {
nl_object_get((struct nl_object *) fam);
return fam;
}
}
return NULL;
}
/**
* @name Resolver
* @{
*/
/**
* Look up generic netlink family by family name in the provided cache.
* @arg cache Generic netlink family cache.
* @arg name Family name.
*
* Searches through the cache looking for a registered family
* matching the specified name. The caller will own a reference
* on the returned object which needs to be given back after
* usage using genl_family_put().
*
* @return Generic netlink family object or NULL if no match was found.
*/
struct genl_family *genl_ctrl_search_by_name(struct nl_cache *cache,
const char *name)
{
struct genl_family *fam;
if (cache->c_ops != &genl_ctrl_ops)
BUG();
nl_list_for_each_entry(fam, &cache->c_items, ce_list) {
if (!strcmp(name, fam->gf_name)) {
nl_object_get((struct nl_object *) fam);
return fam;
}
}
return NULL;
}
/** @} */
/**
* Resolve generic netlink family name to its identifier
* @arg sk Netlink socket.
* @arg name Name of generic netlink family
*
* Resolves the generic netlink family name to its identifer and returns
* it.
*
* @return A positive identifier or a negative error code.
*/
int genl_ctrl_resolve(struct nl_sock *sk, const char *name)
{
struct nl_cache *cache;
struct genl_family *family;
int err;
if ((err = genl_ctrl_alloc_cache(sk, &cache)) < 0)
return err;
family = genl_ctrl_search_by_name(cache, name);
if (family == NULL) {
err = -NLE_OBJ_NOTFOUND;
goto errout;
}
err = genl_family_get_id(family);
genl_family_put(family);
errout:
nl_cache_free(cache);
return err;
}
/** @} */
static struct genl_cmd genl_cmds[] = {
{
.c_id = CTRL_CMD_NEWFAMILY,
.c_name = "NEWFAMILY" ,
.c_maxattr = CTRL_ATTR_MAX,
.c_attr_policy = ctrl_policy,
.c_msg_parser = ctrl_msg_parser,
},
{
.c_id = CTRL_CMD_DELFAMILY,
.c_name = "DELFAMILY" ,
},
{
.c_id = CTRL_CMD_GETFAMILY,
.c_name = "GETFAMILY" ,
},
{
.c_id = CTRL_CMD_NEWOPS,
.c_name = "NEWOPS" ,
},
{
.c_id = CTRL_CMD_DELOPS,
.c_name = "DELOPS" ,
},
};
static struct genl_ops genl_ops = {
.o_cmds = genl_cmds,
.o_ncmds = ARRAY_SIZE(genl_cmds),
};
/** @cond SKIP */
extern struct nl_object_ops genl_family_ops;
/** @endcond */
static struct nl_cache_ops genl_ctrl_ops = {
.co_name = "genl/family",
.co_hdrsize = GENL_HDRSIZE(0),
.co_msgtypes = GENL_FAMILY(GENL_ID_CTRL, "nlctrl"),
.co_genl = &genl_ops,
.co_protocol = NETLINK_GENERIC,
.co_request_update = ctrl_request_update,
.co_obj_ops = &genl_family_ops,
};
static void __init ctrl_init(void)
{
genl_register(&genl_ctrl_ops);
}
static void __exit ctrl_exit(void)
{
genl_unregister(&genl_ctrl_ops);
}
/** @} */