forked from Minki/linux
fc9e50f5a5
The start callback allows the caller to set up a context for the dump callbacks. Presumably, the context can then be destroyed in the done callback. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
432 lines
13 KiB
C
432 lines
13 KiB
C
#ifndef __NET_GENERIC_NETLINK_H
|
|
#define __NET_GENERIC_NETLINK_H
|
|
|
|
#include <linux/genetlink.h>
|
|
#include <net/netlink.h>
|
|
#include <net/net_namespace.h>
|
|
|
|
#define GENLMSG_DEFAULT_SIZE (NLMSG_DEFAULT_SIZE - GENL_HDRLEN)
|
|
|
|
/**
|
|
* struct genl_multicast_group - generic netlink multicast group
|
|
* @name: name of the multicast group, names are per-family
|
|
*/
|
|
struct genl_multicast_group {
|
|
char name[GENL_NAMSIZ];
|
|
};
|
|
|
|
struct genl_ops;
|
|
struct genl_info;
|
|
|
|
/**
|
|
* struct genl_family - generic netlink family
|
|
* @id: protocol family idenfitier
|
|
* @hdrsize: length of user specific header in bytes
|
|
* @name: name of family
|
|
* @version: protocol version
|
|
* @maxattr: maximum number of attributes supported
|
|
* @netnsok: set to true if the family can handle network
|
|
* namespaces and should be presented in all of them
|
|
* @parallel_ops: operations can be called in parallel and aren't
|
|
* synchronized by the core genetlink code
|
|
* @pre_doit: called before an operation's doit callback, it may
|
|
* do additional, common, filtering and return an error
|
|
* @post_doit: called after an operation's doit callback, it may
|
|
* undo operations done by pre_doit, for example release locks
|
|
* @mcast_bind: a socket bound to the given multicast group (which
|
|
* is given as the offset into the groups array)
|
|
* @mcast_unbind: a socket was unbound from the given multicast group.
|
|
* Note that unbind() will not be called symmetrically if the
|
|
* generic netlink family is removed while there are still open
|
|
* sockets.
|
|
* @attrbuf: buffer to store parsed attributes
|
|
* @family_list: family list
|
|
* @mcgrps: multicast groups used by this family (private)
|
|
* @n_mcgrps: number of multicast groups (private)
|
|
* @mcgrp_offset: starting number of multicast group IDs in this family
|
|
* @ops: the operations supported by this family (private)
|
|
* @n_ops: number of operations supported by this family (private)
|
|
*/
|
|
struct genl_family {
|
|
unsigned int id;
|
|
unsigned int hdrsize;
|
|
char name[GENL_NAMSIZ];
|
|
unsigned int version;
|
|
unsigned int maxattr;
|
|
bool netnsok;
|
|
bool parallel_ops;
|
|
int (*pre_doit)(const struct genl_ops *ops,
|
|
struct sk_buff *skb,
|
|
struct genl_info *info);
|
|
void (*post_doit)(const struct genl_ops *ops,
|
|
struct sk_buff *skb,
|
|
struct genl_info *info);
|
|
int (*mcast_bind)(struct net *net, int group);
|
|
void (*mcast_unbind)(struct net *net, int group);
|
|
struct nlattr ** attrbuf; /* private */
|
|
const struct genl_ops * ops; /* private */
|
|
const struct genl_multicast_group *mcgrps; /* private */
|
|
unsigned int n_ops; /* private */
|
|
unsigned int n_mcgrps; /* private */
|
|
unsigned int mcgrp_offset; /* private */
|
|
struct list_head family_list; /* private */
|
|
struct module *module;
|
|
};
|
|
|
|
/**
|
|
* struct genl_info - receiving information
|
|
* @snd_seq: sending sequence number
|
|
* @snd_portid: netlink portid of sender
|
|
* @nlhdr: netlink message header
|
|
* @genlhdr: generic netlink message header
|
|
* @userhdr: user specific header
|
|
* @attrs: netlink attributes
|
|
* @_net: network namespace
|
|
* @user_ptr: user pointers
|
|
* @dst_sk: destination socket
|
|
*/
|
|
struct genl_info {
|
|
u32 snd_seq;
|
|
u32 snd_portid;
|
|
struct nlmsghdr * nlhdr;
|
|
struct genlmsghdr * genlhdr;
|
|
void * userhdr;
|
|
struct nlattr ** attrs;
|
|
possible_net_t _net;
|
|
void * user_ptr[2];
|
|
struct sock * dst_sk;
|
|
};
|
|
|
|
static inline struct net *genl_info_net(struct genl_info *info)
|
|
{
|
|
return read_pnet(&info->_net);
|
|
}
|
|
|
|
static inline void genl_info_net_set(struct genl_info *info, struct net *net)
|
|
{
|
|
write_pnet(&info->_net, net);
|
|
}
|
|
|
|
/**
|
|
* struct genl_ops - generic netlink operations
|
|
* @cmd: command identifier
|
|
* @internal_flags: flags used by the family
|
|
* @flags: flags
|
|
* @policy: attribute validation policy
|
|
* @doit: standard command callback
|
|
* @start: start callback for dumps
|
|
* @dumpit: callback for dumpers
|
|
* @done: completion callback for dumps
|
|
* @ops_list: operations list
|
|
*/
|
|
struct genl_ops {
|
|
const struct nla_policy *policy;
|
|
int (*doit)(struct sk_buff *skb,
|
|
struct genl_info *info);
|
|
int (*start)(struct netlink_callback *cb);
|
|
int (*dumpit)(struct sk_buff *skb,
|
|
struct netlink_callback *cb);
|
|
int (*done)(struct netlink_callback *cb);
|
|
u8 cmd;
|
|
u8 internal_flags;
|
|
u8 flags;
|
|
};
|
|
|
|
int __genl_register_family(struct genl_family *family);
|
|
|
|
static inline int genl_register_family(struct genl_family *family)
|
|
{
|
|
family->module = THIS_MODULE;
|
|
return __genl_register_family(family);
|
|
}
|
|
|
|
/**
|
|
* genl_register_family_with_ops - register a generic netlink family with ops
|
|
* @family: generic netlink family
|
|
* @ops: operations to be registered
|
|
* @n_ops: number of elements to register
|
|
*
|
|
* Registers the specified family and operations from the specified table.
|
|
* Only one family may be registered with the same family name or identifier.
|
|
*
|
|
* The family id may equal GENL_ID_GENERATE causing an unique id to
|
|
* be automatically generated and assigned.
|
|
*
|
|
* Either a doit or dumpit callback must be specified for every registered
|
|
* operation or the function will fail. Only one operation structure per
|
|
* command identifier may be registered.
|
|
*
|
|
* See include/net/genetlink.h for more documenation on the operations
|
|
* structure.
|
|
*
|
|
* Return 0 on success or a negative error code.
|
|
*/
|
|
static inline int
|
|
_genl_register_family_with_ops_grps(struct genl_family *family,
|
|
const struct genl_ops *ops, size_t n_ops,
|
|
const struct genl_multicast_group *mcgrps,
|
|
size_t n_mcgrps)
|
|
{
|
|
family->module = THIS_MODULE;
|
|
family->ops = ops;
|
|
family->n_ops = n_ops;
|
|
family->mcgrps = mcgrps;
|
|
family->n_mcgrps = n_mcgrps;
|
|
return __genl_register_family(family);
|
|
}
|
|
|
|
#define genl_register_family_with_ops(family, ops) \
|
|
_genl_register_family_with_ops_grps((family), \
|
|
(ops), ARRAY_SIZE(ops), \
|
|
NULL, 0)
|
|
#define genl_register_family_with_ops_groups(family, ops, grps) \
|
|
_genl_register_family_with_ops_grps((family), \
|
|
(ops), ARRAY_SIZE(ops), \
|
|
(grps), ARRAY_SIZE(grps))
|
|
|
|
int genl_unregister_family(struct genl_family *family);
|
|
void genl_notify(struct genl_family *family, struct sk_buff *skb,
|
|
struct genl_info *info, u32 group, gfp_t flags);
|
|
|
|
struct sk_buff *genlmsg_new_unicast(size_t payload, struct genl_info *info,
|
|
gfp_t flags);
|
|
void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
|
|
struct genl_family *family, int flags, u8 cmd);
|
|
|
|
/**
|
|
* genlmsg_nlhdr - Obtain netlink header from user specified header
|
|
* @user_hdr: user header as returned from genlmsg_put()
|
|
* @family: generic netlink family
|
|
*
|
|
* Returns pointer to netlink header.
|
|
*/
|
|
static inline struct nlmsghdr *genlmsg_nlhdr(void *user_hdr,
|
|
struct genl_family *family)
|
|
{
|
|
return (struct nlmsghdr *)((char *)user_hdr -
|
|
family->hdrsize -
|
|
GENL_HDRLEN -
|
|
NLMSG_HDRLEN);
|
|
}
|
|
|
|
/**
|
|
* genlmsg_parse - parse attributes of a genetlink message
|
|
* @nlh: netlink message header
|
|
* @family: genetlink message family
|
|
* @tb: destination array with maxtype+1 elements
|
|
* @maxtype: maximum attribute type to be expected
|
|
* @policy: validation policy
|
|
* */
|
|
static inline int genlmsg_parse(const struct nlmsghdr *nlh,
|
|
const struct genl_family *family,
|
|
struct nlattr *tb[], int maxtype,
|
|
const struct nla_policy *policy)
|
|
{
|
|
return nlmsg_parse(nlh, family->hdrsize + GENL_HDRLEN, tb, maxtype,
|
|
policy);
|
|
}
|
|
|
|
/**
|
|
* genl_dump_check_consistent - check if sequence is consistent and advertise if not
|
|
* @cb: netlink callback structure that stores the sequence number
|
|
* @user_hdr: user header as returned from genlmsg_put()
|
|
* @family: generic netlink family
|
|
*
|
|
* Cf. nl_dump_check_consistent(), this just provides a wrapper to make it
|
|
* simpler to use with generic netlink.
|
|
*/
|
|
static inline void genl_dump_check_consistent(struct netlink_callback *cb,
|
|
void *user_hdr,
|
|
struct genl_family *family)
|
|
{
|
|
nl_dump_check_consistent(cb, genlmsg_nlhdr(user_hdr, family));
|
|
}
|
|
|
|
/**
|
|
* genlmsg_put_reply - Add generic netlink header to a reply message
|
|
* @skb: socket buffer holding the message
|
|
* @info: receiver info
|
|
* @family: generic netlink family
|
|
* @flags: netlink message flags
|
|
* @cmd: generic netlink command
|
|
*
|
|
* Returns pointer to user specific header
|
|
*/
|
|
static inline void *genlmsg_put_reply(struct sk_buff *skb,
|
|
struct genl_info *info,
|
|
struct genl_family *family,
|
|
int flags, u8 cmd)
|
|
{
|
|
return genlmsg_put(skb, info->snd_portid, info->snd_seq, family,
|
|
flags, cmd);
|
|
}
|
|
|
|
/**
|
|
* genlmsg_end - Finalize a generic netlink message
|
|
* @skb: socket buffer the message is stored in
|
|
* @hdr: user specific header
|
|
*/
|
|
static inline void genlmsg_end(struct sk_buff *skb, void *hdr)
|
|
{
|
|
nlmsg_end(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
|
|
}
|
|
|
|
/**
|
|
* genlmsg_cancel - Cancel construction of a generic netlink message
|
|
* @skb: socket buffer the message is stored in
|
|
* @hdr: generic netlink message header
|
|
*/
|
|
static inline void genlmsg_cancel(struct sk_buff *skb, void *hdr)
|
|
{
|
|
if (hdr)
|
|
nlmsg_cancel(skb, hdr - GENL_HDRLEN - NLMSG_HDRLEN);
|
|
}
|
|
|
|
/**
|
|
* genlmsg_multicast_netns - multicast a netlink message to a specific netns
|
|
* @family: the generic netlink family
|
|
* @net: the net namespace
|
|
* @skb: netlink message as socket buffer
|
|
* @portid: own netlink portid to avoid sending to yourself
|
|
* @group: offset of multicast group in groups array
|
|
* @flags: allocation flags
|
|
*/
|
|
static inline int genlmsg_multicast_netns(struct genl_family *family,
|
|
struct net *net, struct sk_buff *skb,
|
|
u32 portid, unsigned int group, gfp_t flags)
|
|
{
|
|
if (WARN_ON_ONCE(group >= family->n_mcgrps))
|
|
return -EINVAL;
|
|
group = family->mcgrp_offset + group;
|
|
return nlmsg_multicast(net->genl_sock, skb, portid, group, flags);
|
|
}
|
|
|
|
/**
|
|
* genlmsg_multicast - multicast a netlink message to the default netns
|
|
* @family: the generic netlink family
|
|
* @skb: netlink message as socket buffer
|
|
* @portid: own netlink portid to avoid sending to yourself
|
|
* @group: offset of multicast group in groups array
|
|
* @flags: allocation flags
|
|
*/
|
|
static inline int genlmsg_multicast(struct genl_family *family,
|
|
struct sk_buff *skb, u32 portid,
|
|
unsigned int group, gfp_t flags)
|
|
{
|
|
return genlmsg_multicast_netns(family, &init_net, skb,
|
|
portid, group, flags);
|
|
}
|
|
|
|
/**
|
|
* genlmsg_multicast_allns - multicast a netlink message to all net namespaces
|
|
* @family: the generic netlink family
|
|
* @skb: netlink message as socket buffer
|
|
* @portid: own netlink portid to avoid sending to yourself
|
|
* @group: offset of multicast group in groups array
|
|
* @flags: allocation flags
|
|
*
|
|
* This function must hold the RTNL or rcu_read_lock().
|
|
*/
|
|
int genlmsg_multicast_allns(struct genl_family *family,
|
|
struct sk_buff *skb, u32 portid,
|
|
unsigned int group, gfp_t flags);
|
|
|
|
/**
|
|
* genlmsg_unicast - unicast a netlink message
|
|
* @skb: netlink message as socket buffer
|
|
* @portid: netlink portid of the destination socket
|
|
*/
|
|
static inline int genlmsg_unicast(struct net *net, struct sk_buff *skb, u32 portid)
|
|
{
|
|
return nlmsg_unicast(net->genl_sock, skb, portid);
|
|
}
|
|
|
|
/**
|
|
* genlmsg_reply - reply to a request
|
|
* @skb: netlink message to be sent back
|
|
* @info: receiver information
|
|
*/
|
|
static inline int genlmsg_reply(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
return genlmsg_unicast(genl_info_net(info), skb, info->snd_portid);
|
|
}
|
|
|
|
/**
|
|
* gennlmsg_data - head of message payload
|
|
* @gnlh: genetlink message header
|
|
*/
|
|
static inline void *genlmsg_data(const struct genlmsghdr *gnlh)
|
|
{
|
|
return ((unsigned char *) gnlh + GENL_HDRLEN);
|
|
}
|
|
|
|
/**
|
|
* genlmsg_len - length of message payload
|
|
* @gnlh: genetlink message header
|
|
*/
|
|
static inline int genlmsg_len(const struct genlmsghdr *gnlh)
|
|
{
|
|
struct nlmsghdr *nlh = (struct nlmsghdr *)((unsigned char *)gnlh -
|
|
NLMSG_HDRLEN);
|
|
return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
|
|
}
|
|
|
|
/**
|
|
* genlmsg_msg_size - length of genetlink message not including padding
|
|
* @payload: length of message payload
|
|
*/
|
|
static inline int genlmsg_msg_size(int payload)
|
|
{
|
|
return GENL_HDRLEN + payload;
|
|
}
|
|
|
|
/**
|
|
* genlmsg_total_size - length of genetlink message including padding
|
|
* @payload: length of message payload
|
|
*/
|
|
static inline int genlmsg_total_size(int payload)
|
|
{
|
|
return NLMSG_ALIGN(genlmsg_msg_size(payload));
|
|
}
|
|
|
|
/**
|
|
* genlmsg_new - Allocate a new generic netlink message
|
|
* @payload: size of the message payload
|
|
* @flags: the type of memory to allocate.
|
|
*/
|
|
static inline struct sk_buff *genlmsg_new(size_t payload, gfp_t flags)
|
|
{
|
|
return nlmsg_new(genlmsg_total_size(payload), flags);
|
|
}
|
|
|
|
/**
|
|
* genl_set_err - report error to genetlink broadcast listeners
|
|
* @family: the generic netlink family
|
|
* @net: the network namespace to report the error to
|
|
* @portid: the PORTID of a process that we want to skip (if any)
|
|
* @group: the broadcast group that will notice the error
|
|
* (this is the offset of the multicast group in the groups array)
|
|
* @code: error code, must be negative (as usual in kernelspace)
|
|
*
|
|
* This function returns the number of broadcast listeners that have set the
|
|
* NETLINK_RECV_NO_ENOBUFS socket option.
|
|
*/
|
|
static inline int genl_set_err(struct genl_family *family, struct net *net,
|
|
u32 portid, u32 group, int code)
|
|
{
|
|
if (WARN_ON_ONCE(group >= family->n_mcgrps))
|
|
return -EINVAL;
|
|
group = family->mcgrp_offset + group;
|
|
return netlink_set_err(net->genl_sock, portid, group, code);
|
|
}
|
|
|
|
static inline int genl_has_listeners(struct genl_family *family,
|
|
struct net *net, unsigned int group)
|
|
{
|
|
if (WARN_ON_ONCE(group >= family->n_mcgrps))
|
|
return -EINVAL;
|
|
group = family->mcgrp_offset + group;
|
|
return netlink_has_listeners(net->genl_sock, group);
|
|
}
|
|
#endif /* __NET_GENERIC_NETLINK_H */
|