/*
* lib/route/qdisc.c Queueing Disciplines
*
* 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) 2003-2011 Thomas Graf <tgraf@suug.ch>
*/
/**
* @ingroup tc
* @defgroup qdisc Queueing Disciplines
* @{
*/
#include <netlink-private/netlink.h>
#include <netlink-private/tc.h>
#include <netlink/netlink.h>
#include <netlink/utils.h>
#include <netlink/route/link.h>
#include <netlink-private/route/tc-api.h>
#include <netlink/route/qdisc.h>
#include <netlink/route/class.h>
#include <netlink/route/classifier.h>
static struct nl_cache_ops rtnl_qdisc_ops;
static struct nl_object_ops qdisc_obj_ops;
static int qdisc_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
struct nlmsghdr *n, struct nl_parser_param *pp)
{
struct rtnl_qdisc *qdisc;
int err;
if (!(qdisc = rtnl_qdisc_alloc()))
return -NLE_NOMEM;
if ((err = rtnl_tc_msg_parse(n, TC_CAST(qdisc))) < 0)
goto errout;
err = pp->pp_cb(OBJ_CAST(qdisc), pp);
errout:
rtnl_qdisc_put(qdisc);
return err;
}
static int qdisc_request_update(struct nl_cache *c, struct nl_sock *sk)
{
struct tcmsg tchdr = {
.tcm_family = AF_UNSPEC,
.tcm_ifindex = c->c_iarg1,
};
return nl_send_simple(sk, RTM_GETQDISC, NLM_F_DUMP, &tchdr,
sizeof(tchdr));
}
/**
* @name Allocation/Freeing
* @{
*/
struct rtnl_qdisc *rtnl_qdisc_alloc(void)
{
struct rtnl_tc *tc;
tc = TC_CAST(nl_object_alloc(&qdisc_obj_ops));
if (tc)
tc->tc_type = RTNL_TC_TYPE_QDISC;
return (struct rtnl_qdisc *) tc;
}
void rtnl_qdisc_put(struct rtnl_qdisc *qdisc)
{
nl_object_put((struct nl_object *) qdisc);
}
/** @} */
/**
* @name Addition / Modification / Deletion
* @{
*/
static int build_qdisc_msg(struct rtnl_qdisc *qdisc, int type, int flags,
struct nl_msg **result)
{
if (!(qdisc->ce_mask & TCA_ATTR_IFINDEX)) {
APPBUG("ifindex must be specified");
return -NLE_MISSING_ATTR;
}
return rtnl_tc_msg_build(TC_CAST(qdisc), type, flags, result);
}
/**
* Build a netlink message requesting the addition of a qdisc
* @arg qdisc Qdisc to add
* @arg flags Additional netlink message flags
* @arg result Pointer to store resulting netlink message
*
* The behaviour of this function is identical to rtnl_qdisc_add() with
* the exception that it will not send the message but return it int the
* provided return pointer instead.
*
* @see rtnl_qdisc_add()
*
* @return 0 on success or a negative error code.
*/
int rtnl_qdisc_build_add_request(struct rtnl_qdisc *qdisc, int flags,
struct nl_msg **result)
{
if (!(qdisc->ce_mask & (TCA_ATTR_HANDLE | TCA_ATTR_PARENT))) {
APPBUG("handle or parent must be specified");
return -NLE_MISSING_ATTR;
}
return build_qdisc_msg(qdisc, RTM_NEWQDISC, flags, result);
}
/**
* Add qdisc
* @arg sk Netlink socket
* @arg qdisc Qdisc to add
* @arg flags Additional netlink message flags
*
* Builds a \c RTM_NEWQDISC netlink message requesting the addition
* of a new qdisc and sends the message to the kernel. The configuration
* of the qdisc is derived from the attributes of the specified qdisc.
*
* The following flags may be specified:
* - \c NLM_F_CREATE: Create qdisc if it does not exist, otherwise
* -NLE_OBJ_NOTFOUND is returned.
* - \c NLM_F_REPLACE: If another qdisc is already attached to the
* parent, replace it even if the handles mismatch.
* - \c NLM_F_EXCL: Return -NLE_EXISTS if a qdisc with matching
* handle exists already.
*
* Existing qdiscs with matching handles will be updated, unless the
* flag \c NLM_F_EXCL is specified. If their handles do not match, the
* error -NLE_EXISTS is returned unless the flag \c NLM_F_REPLACE is
* specified in which case the existing qdisc is replaced with the new
* one. If no matching qdisc exists, it will be created if the flag
* \c NLM_F_CREATE is set, otherwise the error -NLE_OBJ_NOTFOUND is
* returned.
*
* After sending, the function will wait for the ACK or an eventual
* error message to be received and will therefore block until the
* operation has been completed.
*
* @note Disabling auto-ack (nl_socket_disable_auto_ack()) will cause
* this function to return immediately after sending. In this case,
* it is the responsibility of the caller to handle any error
* messages returned.
*
* @return 0 on success or a negative error code.
*/
int rtnl_qdisc_add(struct nl_sock *sk, struct rtnl_qdisc *qdisc, int flags)
{
struct nl_msg *msg;
int err;
if ((err = rtnl_qdisc_build_add_request(qdisc, flags, &msg)) < 0)
return err;
return nl_send_sync(sk, msg);
}
/**
* Build netlink message requesting the update of a qdisc
* @arg qdisc Qdisc to update
* @arg new Qdisc with updated attributes
* @arg flags Additional netlink message flags
* @arg result Pointer to store resulting netlink message
*
* The behaviour of this function is identical to rtnl_qdisc_update() with
* the exception that it will not send the message but return it in the
* provided return pointer instead.
*
* @see rtnl_qdisc_update()
*
* @return 0 on success or a negative error code.
*/
int rtnl_qdisc_build_update_request(struct rtnl_qdisc *qdisc,
struct rtnl_qdisc *new, int flags,
struct nl_msg **result)
{
if (flags & (NLM_F_CREATE | NLM_F_EXCL)) {
APPBUG("NLM_F_CREATE and NLM_F_EXCL may not be used here, "
"use rtnl_qdisc_add()");
return -NLE_INVAL;
}
if (!(qdisc->ce_mask & TCA_ATTR_IFINDEX)) {
APPBUG("ifindex must be specified");
return -NLE_MISSING_ATTR;
}
if (!(qdisc->ce_mask & (TCA_ATTR_HANDLE | TCA_ATTR_PARENT))) {
APPBUG("handle or parent must be specified");
return -NLE_MISSING_ATTR;
}
rtnl_tc_set_ifindex(TC_CAST(new), qdisc->q_ifindex);
if (qdisc->ce_mask & TCA_ATTR_HANDLE)
rtnl_tc_set_handle(TC_CAST(new), qdisc->q_handle);
if (qdisc->ce_mask & TCA_ATTR_PARENT)
rtnl_tc_set_parent(TC_CAST(new), qdisc->q_parent);
return build_qdisc_msg(new, RTM_NEWQDISC, flags, result);
}
/**
* Update qdisc
* @arg sk Netlink socket
* @arg qdisc Qdisc to update
* @arg new Qdisc with updated attributes
* @arg flags Additional netlink message flags
*
* Builds a \c RTM_NEWQDISC netlink message requesting the update
* of an existing qdisc and sends the message to the kernel.
*
* This function is a varation of rtnl_qdisc_add() to update qdiscs
* if the qdisc to be updated is available as qdisc object. The
* behaviour is identical to the one of rtnl_qdisc_add except that
* before constructing the message, it copies the \c ifindex,
* \c handle, and \c parent from the original \p qdisc to the \p new
* qdisc.
*
* After sending, the function will wait for the ACK or an eventual
* error message to be received and will therefore block until the
* operation has been completed.
*
* @note Disabling auto-ack (nl_socket_disable_auto_ack()) will cause
* this function to return immediately after sending. In this case,
* it is the responsibility of the caller to handle any error
* messages returned.
*
* @return 0 on success or a negative error code.
*/
int rtnl_qdisc_update(struct nl_sock *sk, struct rtnl_qdisc *qdisc,
struct rtnl_qdisc *new, int flags)
{
struct nl_msg *msg;
int err;
err = rtnl_qdisc_build_update_request(qdisc, new, flags, &msg);
if (err < 0)
return err;
return nl_send_sync(sk, msg);
}
/**
* Build netlink message requesting the deletion of a qdisc
* @arg qdisc Qdisc to delete
* @arg result Pointer to store resulting netlink message
*
* The behaviour of this function is identical to rtnl_qdisc_delete() with
* the exception that it will not send the message but return it in the
* provided return pointer instead.
*
* @see rtnl_qdisc_delete()
*
* @return 0 on success or a negative error code.
*/
int rtnl_qdisc_build_delete_request(struct rtnl_qdisc *qdisc,
struct nl_msg **result)
{
struct nl_msg *msg;
struct tcmsg tchdr;
uint32_t required = TCA_ATTR_IFINDEX | TCA_ATTR_PARENT;
if ((qdisc->ce_mask & required) != required) {
APPBUG("ifindex and parent must be specified");
return -NLE_MISSING_ATTR;
}
if (!(msg = nlmsg_alloc_simple(RTM_DELQDISC, 0)))
return -NLE_NOMEM;
memset(&tchdr, 0, sizeof(tchdr));
tchdr.tcm_family = AF_UNSPEC;
tchdr.tcm_ifindex = qdisc->q_ifindex;
tchdr.tcm_parent = qdisc->q_parent;
if (qdisc->ce_mask & TCA_ATTR_HANDLE)
tchdr.tcm_handle = qdisc->q_handle;
if (nlmsg_append(msg, &tchdr, sizeof(tchdr), NLMSG_ALIGNTO) < 0)
goto nla_put_failure;
if (qdisc->ce_mask & TCA_ATTR_KIND)
NLA_PUT_STRING(msg, TCA_KIND, qdisc->q_kind);
*result = msg;
return 0;
nla_put_failure:
nlmsg_free(msg);
return -NLE_MSGSIZE;
}
/**
* Delete qdisc
* @arg sk Netlink socket
* @arg qdisc Qdisc to add
*
* Builds a \c RTM_NEWQDISC netlink message requesting the deletion
* of a qdisc and sends the message to the kernel.
*
* The message is constructed out of the following attributes:
* - \c ifindex and \c parent
* - \c handle (optional, must match if provided)
* - \c kind (optional, must match if provided)
*
* All other qdisc attributes including all qdisc type specific
* attributes are ignored.
*
* After sending, the function will wait for the ACK or an eventual
* error message to be received and will therefore block until the
* operation has been completed.
*
* @note It is not possible to delete default qdiscs.
*
* @note Disabling auto-ack (nl_socket_disable_auto_ack()) will cause
* this function to return immediately after sending. In this case,
* it is the responsibility of the caller to handle any error
* messages returned.
*
* @return 0 on success or a negative error code.
*/
int rtnl_qdisc_delete(struct nl_sock *sk, struct rtnl_qdisc *qdisc)
{
struct nl_msg *msg;
int err;
if ((err = rtnl_qdisc_build_delete_request(qdisc, &msg)) < 0)
return err;
return nl_send_sync(sk, msg);
}
/** @} */
/**
* @name Cache Related Functions
* @{
*/
/**
* Allocate a cache and fill it with all configured qdiscs
* @arg sk Netlink socket
* @arg result Pointer to store the created cache
*
* Allocates a new qdisc cache and fills it with a list of all configured
* qdiscs on all network devices. Release the cache with nl_cache_free().
*
* @return 0 on success or a negative error code.
*/
int rtnl_qdisc_alloc_cache(struct nl_sock *sk, struct nl_cache **result)
{
return nl_cache_alloc_and_fill(&rtnl_qdisc_ops, sk, result);
}
/**
* Search qdisc by interface index and parent
* @arg cache Qdisc cache
* @arg ifindex Interface index
* @arg parent Handle of parent qdisc
*
* Searches a qdisc cache previously allocated with rtnl_qdisc_alloc_cache()
* and searches for a qdisc matching the interface index and parent qdisc.
*
* The reference counter is incremented before returning the qdisc, therefore
* the reference must be given back with rtnl_qdisc_put() after usage.
*
* @return pointer to qdisc inside the cache or NULL if no match was found.
*/
struct rtnl_qdisc *rtnl_qdisc_get_by_parent(struct nl_cache *cache,
int ifindex, uint32_t parent)
{
struct rtnl_qdisc *q;
if (cache->c_ops != &rtnl_qdisc_ops)
return NULL;
nl_list_for_each_entry(q, &cache->c_items, ce_list) {
if (q->q_parent == parent && q->q_ifindex == ifindex) {
nl_object_get((struct nl_object *) q);
return q;
}
}
return NULL;
}
/**
* Search qdisc by interface index and handle
* @arg cache Qdisc cache
* @arg ifindex Interface index
* @arg handle Handle
*
* Searches a qdisc cache previously allocated with rtnl_qdisc_alloc_cache()
* and searches for a qdisc matching the interface index and handle.
*
* The reference counter is incremented before returning the qdisc, therefore
* the reference must be given back with rtnl_qdisc_put() after usage.
*
* @return Qdisc or NULL if no match was found.
*/
struct rtnl_qdisc *rtnl_qdisc_get(struct nl_cache *cache, int ifindex,
uint32_t handle)
{
struct rtnl_qdisc *q;
if (cache->c_ops != &rtnl_qdisc_ops)
return NULL;
nl_list_for_each_entry(q, &cache->c_items, ce_list) {
if (q->q_handle == handle && q->q_ifindex == ifindex) {
nl_object_get((struct nl_object *) q);
return q;
}
}
return NULL;
}
/** @} */
/**
* @name Deprecated Functions
* @{
*/
/**
* Call a callback for each child class of a qdisc (deprecated)
*
* @deprecated Use of this function is deprecated, it does not allow
* to handle the out of memory situation that can occur.
*/
void rtnl_qdisc_foreach_child(struct rtnl_qdisc *qdisc, struct nl_cache *cache,
void (*cb)(struct nl_object *, void *), void *arg)
{
struct rtnl_class *filter;
filter = rtnl_class_alloc();
if (!filter)
return;
rtnl_tc_set_parent(TC_CAST(filter), qdisc->q_handle);
rtnl_tc_set_ifindex(TC_CAST(filter), qdisc->q_ifindex);
rtnl_tc_set_kind(TC_CAST(filter), qdisc->q_kind);
nl_cache_foreach_filter(cache, OBJ_CAST(filter), cb, arg);
rtnl_class_put(filter);
}
/**
* Call a callback for each filter attached to the qdisc (deprecated)
*
* @deprecated Use of this function is deprecated, it does not allow
* to handle the out of memory situation that can occur.
*/
void rtnl_qdisc_foreach_cls(struct rtnl_qdisc *qdisc, struct nl_cache *cache,
void (*cb)(struct nl_object *, void *), void *arg)
{
struct rtnl_cls *filter;
if (!(filter = rtnl_cls_alloc()))
return;
rtnl_tc_set_ifindex(TC_CAST(filter), qdisc->q_ifindex);
rtnl_tc_set_parent(TC_CAST(filter), qdisc->q_parent);
nl_cache_foreach_filter(cache, OBJ_CAST(filter), cb, arg);
rtnl_cls_put(filter);
}
/**
* Build a netlink message requesting the update of a qdisc
*
* @deprecated Use of this function is deprecated in favour of
* rtnl_qdisc_build_update_request() due to the missing
* possibility of specifying additional flags.
*/
int rtnl_qdisc_build_change_request(struct rtnl_qdisc *qdisc,
struct rtnl_qdisc *new,
struct nl_msg **result)
{
return rtnl_qdisc_build_update_request(qdisc, new, NLM_F_REPLACE,
result);
}
/**
* Change attributes of a qdisc
*
* @deprecated Use of this function is deprecated in favour of
* rtnl_qdisc_update() due to the missing possibility of
* specifying additional flags.
*/
int rtnl_qdisc_change(struct nl_sock *sk, struct rtnl_qdisc *qdisc,
struct rtnl_qdisc *new)
{
return rtnl_qdisc_update(sk, qdisc, new, NLM_F_REPLACE);
}
/** @} */
static void qdisc_dump_details(struct rtnl_tc *tc, struct nl_dump_params *p)
{
struct rtnl_qdisc *qdisc = (struct rtnl_qdisc *) tc;
nl_dump(p, "refcnt %u ", qdisc->q_info);
}
static struct rtnl_tc_type_ops qdisc_ops = {
.tt_type = RTNL_TC_TYPE_QDISC,
.tt_dump_prefix = "qdisc",
.tt_dump = {
[NL_DUMP_DETAILS] = qdisc_dump_details,
},
};
static struct nl_cache_ops rtnl_qdisc_ops = {
.co_name = "route/qdisc",
.co_hdrsize = sizeof(struct tcmsg),
.co_msgtypes = {
{ RTM_NEWQDISC, NL_ACT_NEW, "new" },
{ RTM_DELQDISC, NL_ACT_DEL, "del" },
{ RTM_GETQDISC, NL_ACT_GET, "get" },
END_OF_MSGTYPES_LIST,
},
.co_protocol = NETLINK_ROUTE,
.co_groups = tc_groups,
.co_request_update = qdisc_request_update,
.co_msg_parser = qdisc_msg_parser,
.co_obj_ops = &qdisc_obj_ops,
};
static struct nl_object_ops qdisc_obj_ops = {
.oo_name = "route/qdisc",
.oo_size = sizeof(struct rtnl_qdisc),
.oo_free_data = rtnl_tc_free_data,
.oo_clone = rtnl_tc_clone,
.oo_dump = {
[NL_DUMP_LINE] = rtnl_tc_dump_line,
[NL_DUMP_DETAILS] = rtnl_tc_dump_details,
[NL_DUMP_STATS] = rtnl_tc_dump_stats,
},
.oo_compare = rtnl_tc_compare,
.oo_id_attrs = (TCA_ATTR_IFINDEX | TCA_ATTR_HANDLE),
};
static void __init qdisc_init(void)
{
rtnl_tc_type_register(&qdisc_ops);
nl_cache_mngt_register(&rtnl_qdisc_ops);
}
static void __exit qdisc_exit(void)
{
nl_cache_mngt_unregister(&rtnl_qdisc_ops);
rtnl_tc_type_unregister(&qdisc_ops);
}
/** @} */