forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
427 lines
13 KiB
427 lines
13 KiB
#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 |
|
*/ |
|
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]; |
|
}; |
|
|
|
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; |
|
} __do_const; |
|
|
|
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); |
|
|
|
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 */
|
|
|