mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-27 06:34:11 +08:00
568b742a9d
In some situations some netlink attributes may be used for output only (kernel->userspace) or may be reserved for future use. It's then helpful to be able to prevent userspace from using them in messages sent to the kernel, since they'd otherwise be ignored and any future will become impossible if this happens. Add NLA_REJECT to the policy which does nothing but reject (with EINVAL) validation of any messages containing this attribute. Allow for returning a specific extended ACK error message in the validation_data pointer. While at it clear up the documentation a bit - the NLA_BITFIELD32 documentation was added to the list of len field descriptions. Also, use NL_SET_BAD_ATTR() in one place where it's open-coded. The specific case I have in mind now is a shared nested attribute containing request/response data, and it would be pointless and potentially confusing to have userspace include response data in the messages that actually contain a request. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1435 lines
41 KiB
C
1435 lines
41 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef __NET_NETLINK_H
|
|
#define __NET_NETLINK_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/netlink.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/in6.h>
|
|
|
|
/* ========================================================================
|
|
* Netlink Messages and Attributes Interface (As Seen On TV)
|
|
* ------------------------------------------------------------------------
|
|
* Messages Interface
|
|
* ------------------------------------------------------------------------
|
|
*
|
|
* Message Format:
|
|
* <--- nlmsg_total_size(payload) --->
|
|
* <-- nlmsg_msg_size(payload) ->
|
|
* +----------+- - -+-------------+- - -+-------- - -
|
|
* | nlmsghdr | Pad | Payload | Pad | nlmsghdr
|
|
* +----------+- - -+-------------+- - -+-------- - -
|
|
* nlmsg_data(nlh)---^ ^
|
|
* nlmsg_next(nlh)-----------------------+
|
|
*
|
|
* Payload Format:
|
|
* <---------------------- nlmsg_len(nlh) --------------------->
|
|
* <------ hdrlen ------> <- nlmsg_attrlen(nlh, hdrlen) ->
|
|
* +----------------------+- - -+--------------------------------+
|
|
* | Family Header | Pad | Attributes |
|
|
* +----------------------+- - -+--------------------------------+
|
|
* nlmsg_attrdata(nlh, hdrlen)---^
|
|
*
|
|
* Data Structures:
|
|
* struct nlmsghdr netlink message header
|
|
*
|
|
* Message Construction:
|
|
* nlmsg_new() create a new netlink message
|
|
* nlmsg_put() add a netlink message to an skb
|
|
* nlmsg_put_answer() callback based nlmsg_put()
|
|
* nlmsg_end() finalize netlink message
|
|
* nlmsg_get_pos() return current position in message
|
|
* nlmsg_trim() trim part of message
|
|
* nlmsg_cancel() cancel message construction
|
|
* nlmsg_free() free a netlink message
|
|
*
|
|
* Message Sending:
|
|
* nlmsg_multicast() multicast message to several groups
|
|
* nlmsg_unicast() unicast a message to a single socket
|
|
* nlmsg_notify() send notification message
|
|
*
|
|
* Message Length Calculations:
|
|
* nlmsg_msg_size(payload) length of message w/o padding
|
|
* nlmsg_total_size(payload) length of message w/ padding
|
|
* nlmsg_padlen(payload) length of padding at tail
|
|
*
|
|
* Message Payload Access:
|
|
* nlmsg_data(nlh) head of message payload
|
|
* nlmsg_len(nlh) length of message payload
|
|
* nlmsg_attrdata(nlh, hdrlen) head of attributes data
|
|
* nlmsg_attrlen(nlh, hdrlen) length of attributes data
|
|
*
|
|
* Message Parsing:
|
|
* nlmsg_ok(nlh, remaining) does nlh fit into remaining bytes?
|
|
* nlmsg_next(nlh, remaining) get next netlink message
|
|
* nlmsg_parse() parse attributes of a message
|
|
* nlmsg_find_attr() find an attribute in a message
|
|
* nlmsg_for_each_msg() loop over all messages
|
|
* nlmsg_validate() validate netlink message incl. attrs
|
|
* nlmsg_for_each_attr() loop over all attributes
|
|
*
|
|
* Misc:
|
|
* nlmsg_report() report back to application?
|
|
*
|
|
* ------------------------------------------------------------------------
|
|
* Attributes Interface
|
|
* ------------------------------------------------------------------------
|
|
*
|
|
* Attribute Format:
|
|
* <------- nla_total_size(payload) ------->
|
|
* <---- nla_attr_size(payload) ----->
|
|
* +----------+- - -+- - - - - - - - - +- - -+-------- - -
|
|
* | Header | Pad | Payload | Pad | Header
|
|
* +----------+- - -+- - - - - - - - - +- - -+-------- - -
|
|
* <- nla_len(nla) -> ^
|
|
* nla_data(nla)----^ |
|
|
* nla_next(nla)-----------------------------'
|
|
*
|
|
* Data Structures:
|
|
* struct nlattr netlink attribute header
|
|
*
|
|
* Attribute Construction:
|
|
* nla_reserve(skb, type, len) reserve room for an attribute
|
|
* nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr
|
|
* nla_put(skb, type, len, data) add attribute to skb
|
|
* nla_put_nohdr(skb, len, data) add attribute w/o hdr
|
|
* nla_append(skb, len, data) append data to skb
|
|
*
|
|
* Attribute Construction for Basic Types:
|
|
* nla_put_u8(skb, type, value) add u8 attribute to skb
|
|
* nla_put_u16(skb, type, value) add u16 attribute to skb
|
|
* nla_put_u32(skb, type, value) add u32 attribute to skb
|
|
* nla_put_u64_64bit(skb, type,
|
|
* value, padattr) add u64 attribute to skb
|
|
* nla_put_s8(skb, type, value) add s8 attribute to skb
|
|
* nla_put_s16(skb, type, value) add s16 attribute to skb
|
|
* nla_put_s32(skb, type, value) add s32 attribute to skb
|
|
* nla_put_s64(skb, type, value,
|
|
* padattr) add s64 attribute to skb
|
|
* nla_put_string(skb, type, str) add string attribute to skb
|
|
* nla_put_flag(skb, type) add flag attribute to skb
|
|
* nla_put_msecs(skb, type, jiffies,
|
|
* padattr) add msecs attribute to skb
|
|
* nla_put_in_addr(skb, type, addr) add IPv4 address attribute to skb
|
|
* nla_put_in6_addr(skb, type, addr) add IPv6 address attribute to skb
|
|
*
|
|
* Nested Attributes Construction:
|
|
* nla_nest_start(skb, type) start a nested attribute
|
|
* nla_nest_end(skb, nla) finalize a nested attribute
|
|
* nla_nest_cancel(skb, nla) cancel nested attribute construction
|
|
*
|
|
* Attribute Length Calculations:
|
|
* nla_attr_size(payload) length of attribute w/o padding
|
|
* nla_total_size(payload) length of attribute w/ padding
|
|
* nla_padlen(payload) length of padding
|
|
*
|
|
* Attribute Payload Access:
|
|
* nla_data(nla) head of attribute payload
|
|
* nla_len(nla) length of attribute payload
|
|
*
|
|
* Attribute Payload Access for Basic Types:
|
|
* nla_get_u8(nla) get payload for a u8 attribute
|
|
* nla_get_u16(nla) get payload for a u16 attribute
|
|
* nla_get_u32(nla) get payload for a u32 attribute
|
|
* nla_get_u64(nla) get payload for a u64 attribute
|
|
* nla_get_s8(nla) get payload for a s8 attribute
|
|
* nla_get_s16(nla) get payload for a s16 attribute
|
|
* nla_get_s32(nla) get payload for a s32 attribute
|
|
* nla_get_s64(nla) get payload for a s64 attribute
|
|
* nla_get_flag(nla) return 1 if flag is true
|
|
* nla_get_msecs(nla) get payload for a msecs attribute
|
|
*
|
|
* Attribute Misc:
|
|
* nla_memcpy(dest, nla, count) copy attribute into memory
|
|
* nla_memcmp(nla, data, size) compare attribute with memory area
|
|
* nla_strlcpy(dst, nla, size) copy attribute to a sized string
|
|
* nla_strcmp(nla, str) compare attribute with string
|
|
*
|
|
* Attribute Parsing:
|
|
* nla_ok(nla, remaining) does nla fit into remaining bytes?
|
|
* nla_next(nla, remaining) get next netlink attribute
|
|
* nla_validate() validate a stream of attributes
|
|
* nla_validate_nested() validate a stream of nested attributes
|
|
* nla_find() find attribute in stream of attributes
|
|
* nla_find_nested() find attribute in nested attributes
|
|
* nla_parse() parse and validate stream of attrs
|
|
* nla_parse_nested() parse nested attribuets
|
|
* nla_for_each_attr() loop over all attributes
|
|
* nla_for_each_nested() loop over the nested attributes
|
|
*=========================================================================
|
|
*/
|
|
|
|
/**
|
|
* Standard attribute types to specify validation policy
|
|
*/
|
|
enum {
|
|
NLA_UNSPEC,
|
|
NLA_U8,
|
|
NLA_U16,
|
|
NLA_U32,
|
|
NLA_U64,
|
|
NLA_STRING,
|
|
NLA_FLAG,
|
|
NLA_MSECS,
|
|
NLA_NESTED,
|
|
NLA_NESTED_COMPAT,
|
|
NLA_NUL_STRING,
|
|
NLA_BINARY,
|
|
NLA_S8,
|
|
NLA_S16,
|
|
NLA_S32,
|
|
NLA_S64,
|
|
NLA_BITFIELD32,
|
|
NLA_REJECT,
|
|
__NLA_TYPE_MAX,
|
|
};
|
|
|
|
#define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1)
|
|
|
|
/**
|
|
* struct nla_policy - attribute validation policy
|
|
* @type: Type of attribute or NLA_UNSPEC
|
|
* @len: Type specific length of payload
|
|
*
|
|
* Policies are defined as arrays of this struct, the array must be
|
|
* accessible by attribute type up to the highest identifier to be expected.
|
|
*
|
|
* Meaning of `len' field:
|
|
* NLA_STRING Maximum length of string
|
|
* NLA_NUL_STRING Maximum length of string (excluding NUL)
|
|
* NLA_FLAG Unused
|
|
* NLA_BINARY Maximum length of attribute payload
|
|
* NLA_NESTED Don't use `len' field -- length verification is
|
|
* done by checking len of nested header (or empty)
|
|
* NLA_NESTED_COMPAT Minimum length of structure payload
|
|
* NLA_U8, NLA_U16,
|
|
* NLA_U32, NLA_U64,
|
|
* NLA_S8, NLA_S16,
|
|
* NLA_S32, NLA_S64,
|
|
* NLA_MSECS Leaving the length field zero will verify the
|
|
* given type fits, using it verifies minimum length
|
|
* just like "All other"
|
|
* NLA_BITFIELD32 Unused
|
|
* NLA_REJECT Unused
|
|
* All other Minimum length of attribute payload
|
|
*
|
|
* Meaning of `validation_data' field:
|
|
* NLA_BITFIELD32 This is a 32-bit bitmap/bitselector attribute and
|
|
* validation data must point to a u32 value of valid
|
|
* flags
|
|
* NLA_REJECT This attribute is always rejected and validation data
|
|
* may point to a string to report as the error instead
|
|
* of the generic one in extended ACK.
|
|
* All other Unused
|
|
*
|
|
* Example:
|
|
* static const struct nla_policy my_policy[ATTR_MAX+1] = {
|
|
* [ATTR_FOO] = { .type = NLA_U16 },
|
|
* [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ },
|
|
* [ATTR_BAZ] = { .len = sizeof(struct mystruct) },
|
|
* [ATTR_GOO] = { .type = NLA_BITFIELD32, .validation_data = &myvalidflags },
|
|
* };
|
|
*/
|
|
struct nla_policy {
|
|
u16 type;
|
|
u16 len;
|
|
void *validation_data;
|
|
};
|
|
|
|
/**
|
|
* struct nl_info - netlink source information
|
|
* @nlh: Netlink message header of original request
|
|
* @portid: Netlink PORTID of requesting application
|
|
*/
|
|
struct nl_info {
|
|
struct nlmsghdr *nlh;
|
|
struct net *nl_net;
|
|
u32 portid;
|
|
bool skip_notify;
|
|
};
|
|
|
|
int netlink_rcv_skb(struct sk_buff *skb,
|
|
int (*cb)(struct sk_buff *, struct nlmsghdr *,
|
|
struct netlink_ext_ack *));
|
|
int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
|
|
unsigned int group, int report, gfp_t flags);
|
|
|
|
int nla_validate(const struct nlattr *head, int len, int maxtype,
|
|
const struct nla_policy *policy,
|
|
struct netlink_ext_ack *extack);
|
|
int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
|
|
int len, const struct nla_policy *policy,
|
|
struct netlink_ext_ack *extack);
|
|
int nla_policy_len(const struct nla_policy *, int);
|
|
struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype);
|
|
size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize);
|
|
char *nla_strdup(const struct nlattr *nla, gfp_t flags);
|
|
int nla_memcpy(void *dest, const struct nlattr *src, int count);
|
|
int nla_memcmp(const struct nlattr *nla, const void *data, size_t size);
|
|
int nla_strcmp(const struct nlattr *nla, const char *str);
|
|
struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
|
|
struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype,
|
|
int attrlen, int padattr);
|
|
void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
|
|
struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen);
|
|
struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype,
|
|
int attrlen, int padattr);
|
|
void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen);
|
|
void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
|
|
const void *data);
|
|
void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
|
|
const void *data, int padattr);
|
|
void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
|
|
int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data);
|
|
int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen,
|
|
const void *data, int padattr);
|
|
int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data);
|
|
int nla_append(struct sk_buff *skb, int attrlen, const void *data);
|
|
|
|
/**************************************************************************
|
|
* Netlink Messages
|
|
**************************************************************************/
|
|
|
|
/**
|
|
* nlmsg_msg_size - length of netlink message not including padding
|
|
* @payload: length of message payload
|
|
*/
|
|
static inline int nlmsg_msg_size(int payload)
|
|
{
|
|
return NLMSG_HDRLEN + payload;
|
|
}
|
|
|
|
/**
|
|
* nlmsg_total_size - length of netlink message including padding
|
|
* @payload: length of message payload
|
|
*/
|
|
static inline int nlmsg_total_size(int payload)
|
|
{
|
|
return NLMSG_ALIGN(nlmsg_msg_size(payload));
|
|
}
|
|
|
|
/**
|
|
* nlmsg_padlen - length of padding at the message's tail
|
|
* @payload: length of message payload
|
|
*/
|
|
static inline int nlmsg_padlen(int payload)
|
|
{
|
|
return nlmsg_total_size(payload) - nlmsg_msg_size(payload);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_data - head of message payload
|
|
* @nlh: netlink message header
|
|
*/
|
|
static inline void *nlmsg_data(const struct nlmsghdr *nlh)
|
|
{
|
|
return (unsigned char *) nlh + NLMSG_HDRLEN;
|
|
}
|
|
|
|
/**
|
|
* nlmsg_len - length of message payload
|
|
* @nlh: netlink message header
|
|
*/
|
|
static inline int nlmsg_len(const struct nlmsghdr *nlh)
|
|
{
|
|
return nlh->nlmsg_len - NLMSG_HDRLEN;
|
|
}
|
|
|
|
/**
|
|
* nlmsg_attrdata - head of attributes data
|
|
* @nlh: netlink message header
|
|
* @hdrlen: length of family specific header
|
|
*/
|
|
static inline struct nlattr *nlmsg_attrdata(const struct nlmsghdr *nlh,
|
|
int hdrlen)
|
|
{
|
|
unsigned char *data = nlmsg_data(nlh);
|
|
return (struct nlattr *) (data + NLMSG_ALIGN(hdrlen));
|
|
}
|
|
|
|
/**
|
|
* nlmsg_attrlen - length of attributes data
|
|
* @nlh: netlink message header
|
|
* @hdrlen: length of family specific header
|
|
*/
|
|
static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen)
|
|
{
|
|
return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_ok - check if the netlink message fits into the remaining bytes
|
|
* @nlh: netlink message header
|
|
* @remaining: number of bytes remaining in message stream
|
|
*/
|
|
static inline int nlmsg_ok(const struct nlmsghdr *nlh, int remaining)
|
|
{
|
|
return (remaining >= (int) sizeof(struct nlmsghdr) &&
|
|
nlh->nlmsg_len >= sizeof(struct nlmsghdr) &&
|
|
nlh->nlmsg_len <= remaining);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_next - next netlink message in message stream
|
|
* @nlh: netlink message header
|
|
* @remaining: number of bytes remaining in message stream
|
|
*
|
|
* Returns the next netlink message in the message stream and
|
|
* decrements remaining by the size of the current message.
|
|
*/
|
|
static inline struct nlmsghdr *
|
|
nlmsg_next(const struct nlmsghdr *nlh, int *remaining)
|
|
{
|
|
int totlen = NLMSG_ALIGN(nlh->nlmsg_len);
|
|
|
|
*remaining -= totlen;
|
|
|
|
return (struct nlmsghdr *) ((unsigned char *) nlh + totlen);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_parse - parse attributes of a netlink message
|
|
* @nlh: netlink message header
|
|
* @hdrlen: length of family specific header
|
|
* @tb: destination array with maxtype+1 elements
|
|
* @maxtype: maximum attribute type to be expected
|
|
* @policy: validation policy
|
|
* @extack: extended ACK report struct
|
|
*
|
|
* See nla_parse()
|
|
*/
|
|
static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen,
|
|
struct nlattr *tb[], int maxtype,
|
|
const struct nla_policy *policy,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
|
|
return -EINVAL;
|
|
|
|
return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen),
|
|
nlmsg_attrlen(nlh, hdrlen), policy, extack);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_find_attr - find a specific attribute in a netlink message
|
|
* @nlh: netlink message header
|
|
* @hdrlen: length of familiy specific header
|
|
* @attrtype: type of attribute to look for
|
|
*
|
|
* Returns the first attribute which matches the specified type.
|
|
*/
|
|
static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh,
|
|
int hdrlen, int attrtype)
|
|
{
|
|
return nla_find(nlmsg_attrdata(nlh, hdrlen),
|
|
nlmsg_attrlen(nlh, hdrlen), attrtype);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_validate - validate a netlink message including attributes
|
|
* @nlh: netlinket message header
|
|
* @hdrlen: length of familiy specific header
|
|
* @maxtype: maximum attribute type to be expected
|
|
* @policy: validation policy
|
|
* @extack: extended ACK report struct
|
|
*/
|
|
static inline int nlmsg_validate(const struct nlmsghdr *nlh,
|
|
int hdrlen, int maxtype,
|
|
const struct nla_policy *policy,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
|
|
return -EINVAL;
|
|
|
|
return nla_validate(nlmsg_attrdata(nlh, hdrlen),
|
|
nlmsg_attrlen(nlh, hdrlen), maxtype, policy,
|
|
extack);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_report - need to report back to application?
|
|
* @nlh: netlink message header
|
|
*
|
|
* Returns 1 if a report back to the application is requested.
|
|
*/
|
|
static inline int nlmsg_report(const struct nlmsghdr *nlh)
|
|
{
|
|
return !!(nlh->nlmsg_flags & NLM_F_ECHO);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_for_each_attr - iterate over a stream of attributes
|
|
* @pos: loop counter, set to current attribute
|
|
* @nlh: netlink message header
|
|
* @hdrlen: length of familiy specific header
|
|
* @rem: initialized to len, holds bytes currently remaining in stream
|
|
*/
|
|
#define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \
|
|
nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \
|
|
nlmsg_attrlen(nlh, hdrlen), rem)
|
|
|
|
/**
|
|
* nlmsg_put - Add a new netlink message to an skb
|
|
* @skb: socket buffer to store message in
|
|
* @portid: netlink PORTID of requesting application
|
|
* @seq: sequence number of message
|
|
* @type: message type
|
|
* @payload: length of message payload
|
|
* @flags: message flags
|
|
*
|
|
* Returns NULL if the tailroom of the skb is insufficient to store
|
|
* the message header and payload.
|
|
*/
|
|
static inline struct nlmsghdr *nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
|
|
int type, int payload, int flags)
|
|
{
|
|
if (unlikely(skb_tailroom(skb) < nlmsg_total_size(payload)))
|
|
return NULL;
|
|
|
|
return __nlmsg_put(skb, portid, seq, type, payload, flags);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_put_answer - Add a new callback based netlink message to an skb
|
|
* @skb: socket buffer to store message in
|
|
* @cb: netlink callback
|
|
* @type: message type
|
|
* @payload: length of message payload
|
|
* @flags: message flags
|
|
*
|
|
* Returns NULL if the tailroom of the skb is insufficient to store
|
|
* the message header and payload.
|
|
*/
|
|
static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb,
|
|
struct netlink_callback *cb,
|
|
int type, int payload,
|
|
int flags)
|
|
{
|
|
return nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
|
|
type, payload, flags);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_new - Allocate a new netlink message
|
|
* @payload: size of the message payload
|
|
* @flags: the type of memory to allocate.
|
|
*
|
|
* Use NLMSG_DEFAULT_SIZE if the size of the payload isn't known
|
|
* and a good default is needed.
|
|
*/
|
|
static inline struct sk_buff *nlmsg_new(size_t payload, gfp_t flags)
|
|
{
|
|
return alloc_skb(nlmsg_total_size(payload), flags);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_end - Finalize a netlink message
|
|
* @skb: socket buffer the message is stored in
|
|
* @nlh: netlink message header
|
|
*
|
|
* Corrects the netlink message header to include the appeneded
|
|
* attributes. Only necessary if attributes have been added to
|
|
* the message.
|
|
*/
|
|
static inline void nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh)
|
|
{
|
|
nlh->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)nlh;
|
|
}
|
|
|
|
/**
|
|
* nlmsg_get_pos - return current position in netlink message
|
|
* @skb: socket buffer the message is stored in
|
|
*
|
|
* Returns a pointer to the current tail of the message.
|
|
*/
|
|
static inline void *nlmsg_get_pos(struct sk_buff *skb)
|
|
{
|
|
return skb_tail_pointer(skb);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_trim - Trim message to a mark
|
|
* @skb: socket buffer the message is stored in
|
|
* @mark: mark to trim to
|
|
*
|
|
* Trims the message to the provided mark.
|
|
*/
|
|
static inline void nlmsg_trim(struct sk_buff *skb, const void *mark)
|
|
{
|
|
if (mark) {
|
|
WARN_ON((unsigned char *) mark < skb->data);
|
|
skb_trim(skb, (unsigned char *) mark - skb->data);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* nlmsg_cancel - Cancel construction of a netlink message
|
|
* @skb: socket buffer the message is stored in
|
|
* @nlh: netlink message header
|
|
*
|
|
* Removes the complete netlink message including all
|
|
* attributes from the socket buffer again.
|
|
*/
|
|
static inline void nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh)
|
|
{
|
|
nlmsg_trim(skb, nlh);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_free - free a netlink message
|
|
* @skb: socket buffer of netlink message
|
|
*/
|
|
static inline void nlmsg_free(struct sk_buff *skb)
|
|
{
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
/**
|
|
* nlmsg_multicast - multicast a netlink message
|
|
* @sk: netlink socket to spread messages to
|
|
* @skb: netlink message as socket buffer
|
|
* @portid: own netlink portid to avoid sending to yourself
|
|
* @group: multicast group id
|
|
* @flags: allocation flags
|
|
*/
|
|
static inline int nlmsg_multicast(struct sock *sk, struct sk_buff *skb,
|
|
u32 portid, unsigned int group, gfp_t flags)
|
|
{
|
|
int err;
|
|
|
|
NETLINK_CB(skb).dst_group = group;
|
|
|
|
err = netlink_broadcast(sk, skb, portid, group, flags);
|
|
if (err > 0)
|
|
err = 0;
|
|
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* nlmsg_unicast - unicast a netlink message
|
|
* @sk: netlink socket to spread message to
|
|
* @skb: netlink message as socket buffer
|
|
* @portid: netlink portid of the destination socket
|
|
*/
|
|
static inline int nlmsg_unicast(struct sock *sk, struct sk_buff *skb, u32 portid)
|
|
{
|
|
int err;
|
|
|
|
err = netlink_unicast(sk, skb, portid, MSG_DONTWAIT);
|
|
if (err > 0)
|
|
err = 0;
|
|
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* nlmsg_for_each_msg - iterate over a stream of messages
|
|
* @pos: loop counter, set to current message
|
|
* @head: head of message stream
|
|
* @len: length of message stream
|
|
* @rem: initialized to len, holds bytes currently remaining in stream
|
|
*/
|
|
#define nlmsg_for_each_msg(pos, head, len, rem) \
|
|
for (pos = head, rem = len; \
|
|
nlmsg_ok(pos, rem); \
|
|
pos = nlmsg_next(pos, &(rem)))
|
|
|
|
/**
|
|
* nl_dump_check_consistent - check if sequence is consistent and advertise if not
|
|
* @cb: netlink callback structure that stores the sequence number
|
|
* @nlh: netlink message header to write the flag to
|
|
*
|
|
* This function checks if the sequence (generation) number changed during dump
|
|
* and if it did, advertises it in the netlink message header.
|
|
*
|
|
* The correct way to use it is to set cb->seq to the generation counter when
|
|
* all locks for dumping have been acquired, and then call this function for
|
|
* each message that is generated.
|
|
*
|
|
* Note that due to initialisation concerns, 0 is an invalid sequence number
|
|
* and must not be used by code that uses this functionality.
|
|
*/
|
|
static inline void
|
|
nl_dump_check_consistent(struct netlink_callback *cb,
|
|
struct nlmsghdr *nlh)
|
|
{
|
|
if (cb->prev_seq && cb->seq != cb->prev_seq)
|
|
nlh->nlmsg_flags |= NLM_F_DUMP_INTR;
|
|
cb->prev_seq = cb->seq;
|
|
}
|
|
|
|
/**************************************************************************
|
|
* Netlink Attributes
|
|
**************************************************************************/
|
|
|
|
/**
|
|
* nla_attr_size - length of attribute not including padding
|
|
* @payload: length of payload
|
|
*/
|
|
static inline int nla_attr_size(int payload)
|
|
{
|
|
return NLA_HDRLEN + payload;
|
|
}
|
|
|
|
/**
|
|
* nla_total_size - total length of attribute including padding
|
|
* @payload: length of payload
|
|
*/
|
|
static inline int nla_total_size(int payload)
|
|
{
|
|
return NLA_ALIGN(nla_attr_size(payload));
|
|
}
|
|
|
|
/**
|
|
* nla_padlen - length of padding at the tail of attribute
|
|
* @payload: length of payload
|
|
*/
|
|
static inline int nla_padlen(int payload)
|
|
{
|
|
return nla_total_size(payload) - nla_attr_size(payload);
|
|
}
|
|
|
|
/**
|
|
* nla_type - attribute type
|
|
* @nla: netlink attribute
|
|
*/
|
|
static inline int nla_type(const struct nlattr *nla)
|
|
{
|
|
return nla->nla_type & NLA_TYPE_MASK;
|
|
}
|
|
|
|
/**
|
|
* nla_data - head of payload
|
|
* @nla: netlink attribute
|
|
*/
|
|
static inline void *nla_data(const struct nlattr *nla)
|
|
{
|
|
return (char *) nla + NLA_HDRLEN;
|
|
}
|
|
|
|
/**
|
|
* nla_len - length of payload
|
|
* @nla: netlink attribute
|
|
*/
|
|
static inline int nla_len(const struct nlattr *nla)
|
|
{
|
|
return nla->nla_len - NLA_HDRLEN;
|
|
}
|
|
|
|
/**
|
|
* nla_ok - check if the netlink attribute fits into the remaining bytes
|
|
* @nla: netlink attribute
|
|
* @remaining: number of bytes remaining in attribute stream
|
|
*/
|
|
static inline int nla_ok(const struct nlattr *nla, int remaining)
|
|
{
|
|
return remaining >= (int) sizeof(*nla) &&
|
|
nla->nla_len >= sizeof(*nla) &&
|
|
nla->nla_len <= remaining;
|
|
}
|
|
|
|
/**
|
|
* nla_next - next netlink attribute in attribute stream
|
|
* @nla: netlink attribute
|
|
* @remaining: number of bytes remaining in attribute stream
|
|
*
|
|
* Returns the next netlink attribute in the attribute stream and
|
|
* decrements remaining by the size of the current attribute.
|
|
*/
|
|
static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining)
|
|
{
|
|
unsigned int totlen = NLA_ALIGN(nla->nla_len);
|
|
|
|
*remaining -= totlen;
|
|
return (struct nlattr *) ((char *) nla + totlen);
|
|
}
|
|
|
|
/**
|
|
* nla_find_nested - find attribute in a set of nested attributes
|
|
* @nla: attribute containing the nested attributes
|
|
* @attrtype: type of attribute to look for
|
|
*
|
|
* Returns the first attribute which matches the specified type.
|
|
*/
|
|
static inline struct nlattr *
|
|
nla_find_nested(const struct nlattr *nla, int attrtype)
|
|
{
|
|
return nla_find(nla_data(nla), nla_len(nla), attrtype);
|
|
}
|
|
|
|
/**
|
|
* nla_parse_nested - parse nested attributes
|
|
* @tb: destination array with maxtype+1 elements
|
|
* @maxtype: maximum attribute type to be expected
|
|
* @nla: attribute containing the nested attributes
|
|
* @policy: validation policy
|
|
* @extack: extended ACK report struct
|
|
*
|
|
* See nla_parse()
|
|
*/
|
|
static inline int nla_parse_nested(struct nlattr *tb[], int maxtype,
|
|
const struct nlattr *nla,
|
|
const struct nla_policy *policy,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy,
|
|
extack);
|
|
}
|
|
|
|
/**
|
|
* nla_put_u8 - Add a u8 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_u8(struct sk_buff *skb, int attrtype, u8 value)
|
|
{
|
|
/* temporary variables to work around GCC PR81715 with asan-stack=1 */
|
|
u8 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(u8), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_u16 - Add a u16 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_u16(struct sk_buff *skb, int attrtype, u16 value)
|
|
{
|
|
u16 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(u16), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_be16 - Add a __be16 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_be16(struct sk_buff *skb, int attrtype, __be16 value)
|
|
{
|
|
__be16 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(__be16), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_net16 - Add 16-bit network byte order netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_net16(struct sk_buff *skb, int attrtype, __be16 value)
|
|
{
|
|
__be16 tmp = value;
|
|
|
|
return nla_put_be16(skb, attrtype | NLA_F_NET_BYTEORDER, tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_le16 - Add a __le16 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_le16(struct sk_buff *skb, int attrtype, __le16 value)
|
|
{
|
|
__le16 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(__le16), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_u32 - Add a u32 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_u32(struct sk_buff *skb, int attrtype, u32 value)
|
|
{
|
|
u32 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(u32), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_be32 - Add a __be32 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_be32(struct sk_buff *skb, int attrtype, __be32 value)
|
|
{
|
|
__be32 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(__be32), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_net32 - Add 32-bit network byte order netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_net32(struct sk_buff *skb, int attrtype, __be32 value)
|
|
{
|
|
__be32 tmp = value;
|
|
|
|
return nla_put_be32(skb, attrtype | NLA_F_NET_BYTEORDER, tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_le32 - Add a __le32 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_le32(struct sk_buff *skb, int attrtype, __le32 value)
|
|
{
|
|
__le32 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(__le32), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_u64_64bit - Add a u64 netlink attribute to a skb and align it
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
* @padattr: attribute type for the padding
|
|
*/
|
|
static inline int nla_put_u64_64bit(struct sk_buff *skb, int attrtype,
|
|
u64 value, int padattr)
|
|
{
|
|
u64 tmp = value;
|
|
|
|
return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr);
|
|
}
|
|
|
|
/**
|
|
* nla_put_be64 - Add a __be64 netlink attribute to a socket buffer and align it
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
* @padattr: attribute type for the padding
|
|
*/
|
|
static inline int nla_put_be64(struct sk_buff *skb, int attrtype, __be64 value,
|
|
int padattr)
|
|
{
|
|
__be64 tmp = value;
|
|
|
|
return nla_put_64bit(skb, attrtype, sizeof(__be64), &tmp, padattr);
|
|
}
|
|
|
|
/**
|
|
* nla_put_net64 - Add 64-bit network byte order nlattr to a skb and align it
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
* @padattr: attribute type for the padding
|
|
*/
|
|
static inline int nla_put_net64(struct sk_buff *skb, int attrtype, __be64 value,
|
|
int padattr)
|
|
{
|
|
__be64 tmp = value;
|
|
|
|
return nla_put_be64(skb, attrtype | NLA_F_NET_BYTEORDER, tmp,
|
|
padattr);
|
|
}
|
|
|
|
/**
|
|
* nla_put_le64 - Add a __le64 netlink attribute to a socket buffer and align it
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
* @padattr: attribute type for the padding
|
|
*/
|
|
static inline int nla_put_le64(struct sk_buff *skb, int attrtype, __le64 value,
|
|
int padattr)
|
|
{
|
|
__le64 tmp = value;
|
|
|
|
return nla_put_64bit(skb, attrtype, sizeof(__le64), &tmp, padattr);
|
|
}
|
|
|
|
/**
|
|
* nla_put_s8 - Add a s8 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_s8(struct sk_buff *skb, int attrtype, s8 value)
|
|
{
|
|
s8 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(s8), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_s16 - Add a s16 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_s16(struct sk_buff *skb, int attrtype, s16 value)
|
|
{
|
|
s16 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(s16), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_s32 - Add a s32 netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
*/
|
|
static inline int nla_put_s32(struct sk_buff *skb, int attrtype, s32 value)
|
|
{
|
|
s32 tmp = value;
|
|
|
|
return nla_put(skb, attrtype, sizeof(s32), &tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_s64 - Add a s64 netlink attribute to a socket buffer and align it
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @value: numeric value
|
|
* @padattr: attribute type for the padding
|
|
*/
|
|
static inline int nla_put_s64(struct sk_buff *skb, int attrtype, s64 value,
|
|
int padattr)
|
|
{
|
|
s64 tmp = value;
|
|
|
|
return nla_put_64bit(skb, attrtype, sizeof(s64), &tmp, padattr);
|
|
}
|
|
|
|
/**
|
|
* nla_put_string - Add a string netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @str: NUL terminated string
|
|
*/
|
|
static inline int nla_put_string(struct sk_buff *skb, int attrtype,
|
|
const char *str)
|
|
{
|
|
return nla_put(skb, attrtype, strlen(str) + 1, str);
|
|
}
|
|
|
|
/**
|
|
* nla_put_flag - Add a flag netlink attribute to a socket buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
*/
|
|
static inline int nla_put_flag(struct sk_buff *skb, int attrtype)
|
|
{
|
|
return nla_put(skb, attrtype, 0, NULL);
|
|
}
|
|
|
|
/**
|
|
* nla_put_msecs - Add a msecs netlink attribute to a skb and align it
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @njiffies: number of jiffies to convert to msecs
|
|
* @padattr: attribute type for the padding
|
|
*/
|
|
static inline int nla_put_msecs(struct sk_buff *skb, int attrtype,
|
|
unsigned long njiffies, int padattr)
|
|
{
|
|
u64 tmp = jiffies_to_msecs(njiffies);
|
|
|
|
return nla_put_64bit(skb, attrtype, sizeof(u64), &tmp, padattr);
|
|
}
|
|
|
|
/**
|
|
* nla_put_in_addr - Add an IPv4 address netlink attribute to a socket
|
|
* buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @addr: IPv4 address
|
|
*/
|
|
static inline int nla_put_in_addr(struct sk_buff *skb, int attrtype,
|
|
__be32 addr)
|
|
{
|
|
__be32 tmp = addr;
|
|
|
|
return nla_put_be32(skb, attrtype, tmp);
|
|
}
|
|
|
|
/**
|
|
* nla_put_in6_addr - Add an IPv6 address netlink attribute to a socket
|
|
* buffer
|
|
* @skb: socket buffer to add attribute to
|
|
* @attrtype: attribute type
|
|
* @addr: IPv6 address
|
|
*/
|
|
static inline int nla_put_in6_addr(struct sk_buff *skb, int attrtype,
|
|
const struct in6_addr *addr)
|
|
{
|
|
return nla_put(skb, attrtype, sizeof(*addr), addr);
|
|
}
|
|
|
|
/**
|
|
* nla_get_u32 - return payload of u32 attribute
|
|
* @nla: u32 netlink attribute
|
|
*/
|
|
static inline u32 nla_get_u32(const struct nlattr *nla)
|
|
{
|
|
return *(u32 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_be32 - return payload of __be32 attribute
|
|
* @nla: __be32 netlink attribute
|
|
*/
|
|
static inline __be32 nla_get_be32(const struct nlattr *nla)
|
|
{
|
|
return *(__be32 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_le32 - return payload of __le32 attribute
|
|
* @nla: __le32 netlink attribute
|
|
*/
|
|
static inline __le32 nla_get_le32(const struct nlattr *nla)
|
|
{
|
|
return *(__le32 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_u16 - return payload of u16 attribute
|
|
* @nla: u16 netlink attribute
|
|
*/
|
|
static inline u16 nla_get_u16(const struct nlattr *nla)
|
|
{
|
|
return *(u16 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_be16 - return payload of __be16 attribute
|
|
* @nla: __be16 netlink attribute
|
|
*/
|
|
static inline __be16 nla_get_be16(const struct nlattr *nla)
|
|
{
|
|
return *(__be16 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_le16 - return payload of __le16 attribute
|
|
* @nla: __le16 netlink attribute
|
|
*/
|
|
static inline __le16 nla_get_le16(const struct nlattr *nla)
|
|
{
|
|
return *(__le16 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_u8 - return payload of u8 attribute
|
|
* @nla: u8 netlink attribute
|
|
*/
|
|
static inline u8 nla_get_u8(const struct nlattr *nla)
|
|
{
|
|
return *(u8 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_u64 - return payload of u64 attribute
|
|
* @nla: u64 netlink attribute
|
|
*/
|
|
static inline u64 nla_get_u64(const struct nlattr *nla)
|
|
{
|
|
u64 tmp;
|
|
|
|
nla_memcpy(&tmp, nla, sizeof(tmp));
|
|
|
|
return tmp;
|
|
}
|
|
|
|
/**
|
|
* nla_get_be64 - return payload of __be64 attribute
|
|
* @nla: __be64 netlink attribute
|
|
*/
|
|
static inline __be64 nla_get_be64(const struct nlattr *nla)
|
|
{
|
|
__be64 tmp;
|
|
|
|
nla_memcpy(&tmp, nla, sizeof(tmp));
|
|
|
|
return tmp;
|
|
}
|
|
|
|
/**
|
|
* nla_get_le64 - return payload of __le64 attribute
|
|
* @nla: __le64 netlink attribute
|
|
*/
|
|
static inline __le64 nla_get_le64(const struct nlattr *nla)
|
|
{
|
|
return *(__le64 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_s32 - return payload of s32 attribute
|
|
* @nla: s32 netlink attribute
|
|
*/
|
|
static inline s32 nla_get_s32(const struct nlattr *nla)
|
|
{
|
|
return *(s32 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_s16 - return payload of s16 attribute
|
|
* @nla: s16 netlink attribute
|
|
*/
|
|
static inline s16 nla_get_s16(const struct nlattr *nla)
|
|
{
|
|
return *(s16 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_s8 - return payload of s8 attribute
|
|
* @nla: s8 netlink attribute
|
|
*/
|
|
static inline s8 nla_get_s8(const struct nlattr *nla)
|
|
{
|
|
return *(s8 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_s64 - return payload of s64 attribute
|
|
* @nla: s64 netlink attribute
|
|
*/
|
|
static inline s64 nla_get_s64(const struct nlattr *nla)
|
|
{
|
|
s64 tmp;
|
|
|
|
nla_memcpy(&tmp, nla, sizeof(tmp));
|
|
|
|
return tmp;
|
|
}
|
|
|
|
/**
|
|
* nla_get_flag - return payload of flag attribute
|
|
* @nla: flag netlink attribute
|
|
*/
|
|
static inline int nla_get_flag(const struct nlattr *nla)
|
|
{
|
|
return !!nla;
|
|
}
|
|
|
|
/**
|
|
* nla_get_msecs - return payload of msecs attribute
|
|
* @nla: msecs netlink attribute
|
|
*
|
|
* Returns the number of milliseconds in jiffies.
|
|
*/
|
|
static inline unsigned long nla_get_msecs(const struct nlattr *nla)
|
|
{
|
|
u64 msecs = nla_get_u64(nla);
|
|
|
|
return msecs_to_jiffies((unsigned long) msecs);
|
|
}
|
|
|
|
/**
|
|
* nla_get_in_addr - return payload of IPv4 address attribute
|
|
* @nla: IPv4 address netlink attribute
|
|
*/
|
|
static inline __be32 nla_get_in_addr(const struct nlattr *nla)
|
|
{
|
|
return *(__be32 *) nla_data(nla);
|
|
}
|
|
|
|
/**
|
|
* nla_get_in6_addr - return payload of IPv6 address attribute
|
|
* @nla: IPv6 address netlink attribute
|
|
*/
|
|
static inline struct in6_addr nla_get_in6_addr(const struct nlattr *nla)
|
|
{
|
|
struct in6_addr tmp;
|
|
|
|
nla_memcpy(&tmp, nla, sizeof(tmp));
|
|
return tmp;
|
|
}
|
|
|
|
/**
|
|
* nla_get_bitfield32 - return payload of 32 bitfield attribute
|
|
* @nla: nla_bitfield32 attribute
|
|
*/
|
|
static inline struct nla_bitfield32 nla_get_bitfield32(const struct nlattr *nla)
|
|
{
|
|
struct nla_bitfield32 tmp;
|
|
|
|
nla_memcpy(&tmp, nla, sizeof(tmp));
|
|
return tmp;
|
|
}
|
|
|
|
/**
|
|
* nla_memdup - duplicate attribute memory (kmemdup)
|
|
* @src: netlink attribute to duplicate from
|
|
* @gfp: GFP mask
|
|
*/
|
|
static inline void *nla_memdup(const struct nlattr *src, gfp_t gfp)
|
|
{
|
|
return kmemdup(nla_data(src), nla_len(src), gfp);
|
|
}
|
|
|
|
/**
|
|
* nla_nest_start - Start a new level of nested attributes
|
|
* @skb: socket buffer to add attributes to
|
|
* @attrtype: attribute type of container
|
|
*
|
|
* Returns the container attribute
|
|
*/
|
|
static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
|
|
{
|
|
struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
|
|
|
|
if (nla_put(skb, attrtype, 0, NULL) < 0)
|
|
return NULL;
|
|
|
|
return start;
|
|
}
|
|
|
|
/**
|
|
* nla_nest_end - Finalize nesting of attributes
|
|
* @skb: socket buffer the attributes are stored in
|
|
* @start: container attribute
|
|
*
|
|
* Corrects the container attribute header to include the all
|
|
* appeneded attributes.
|
|
*
|
|
* Returns the total data length of the skb.
|
|
*/
|
|
static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start)
|
|
{
|
|
start->nla_len = skb_tail_pointer(skb) - (unsigned char *)start;
|
|
return skb->len;
|
|
}
|
|
|
|
/**
|
|
* nla_nest_cancel - Cancel nesting of attributes
|
|
* @skb: socket buffer the message is stored in
|
|
* @start: container attribute
|
|
*
|
|
* Removes the container attribute and including all nested
|
|
* attributes. Returns -EMSGSIZE
|
|
*/
|
|
static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start)
|
|
{
|
|
nlmsg_trim(skb, start);
|
|
}
|
|
|
|
/**
|
|
* nla_validate_nested - Validate a stream of nested attributes
|
|
* @start: container attribute
|
|
* @maxtype: maximum attribute type to be expected
|
|
* @policy: validation policy
|
|
* @extack: extended ACK report struct
|
|
*
|
|
* Validates all attributes in the nested attribute stream against the
|
|
* specified policy. Attributes with a type exceeding maxtype will be
|
|
* ignored. See documenation of struct nla_policy for more details.
|
|
*
|
|
* Returns 0 on success or a negative error code.
|
|
*/
|
|
static inline int nla_validate_nested(const struct nlattr *start, int maxtype,
|
|
const struct nla_policy *policy,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
return nla_validate(nla_data(start), nla_len(start), maxtype, policy,
|
|
extack);
|
|
}
|
|
|
|
/**
|
|
* nla_need_padding_for_64bit - test 64-bit alignment of the next attribute
|
|
* @skb: socket buffer the message is stored in
|
|
*
|
|
* Return true if padding is needed to align the next attribute (nla_data()) to
|
|
* a 64-bit aligned area.
|
|
*/
|
|
static inline bool nla_need_padding_for_64bit(struct sk_buff *skb)
|
|
{
|
|
#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
|
|
/* The nlattr header is 4 bytes in size, that's why we test
|
|
* if the skb->data _is_ aligned. A NOP attribute, plus
|
|
* nlattr header for next attribute, will make nla_data()
|
|
* 8-byte aligned.
|
|
*/
|
|
if (IS_ALIGNED((unsigned long)skb_tail_pointer(skb), 8))
|
|
return true;
|
|
#endif
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* nla_align_64bit - 64-bit align the nla_data() of next attribute
|
|
* @skb: socket buffer the message is stored in
|
|
* @padattr: attribute type for the padding
|
|
*
|
|
* Conditionally emit a padding netlink attribute in order to make
|
|
* the next attribute we emit have a 64-bit aligned nla_data() area.
|
|
* This will only be done in architectures which do not have
|
|
* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS defined.
|
|
*
|
|
* Returns zero on success or a negative error code.
|
|
*/
|
|
static inline int nla_align_64bit(struct sk_buff *skb, int padattr)
|
|
{
|
|
if (nla_need_padding_for_64bit(skb) &&
|
|
!nla_reserve(skb, padattr, 0))
|
|
return -EMSGSIZE;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* nla_total_size_64bit - total length of attribute including padding
|
|
* @payload: length of payload
|
|
*/
|
|
static inline int nla_total_size_64bit(int payload)
|
|
{
|
|
return NLA_ALIGN(nla_attr_size(payload))
|
|
#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
|
|
+ NLA_ALIGN(nla_attr_size(0))
|
|
#endif
|
|
;
|
|
}
|
|
|
|
/**
|
|
* nla_for_each_attr - iterate over a stream of attributes
|
|
* @pos: loop counter, set to current attribute
|
|
* @head: head of attribute stream
|
|
* @len: length of attribute stream
|
|
* @rem: initialized to len, holds bytes currently remaining in stream
|
|
*/
|
|
#define nla_for_each_attr(pos, head, len, rem) \
|
|
for (pos = head, rem = len; \
|
|
nla_ok(pos, rem); \
|
|
pos = nla_next(pos, &(rem)))
|
|
|
|
/**
|
|
* nla_for_each_nested - iterate over nested attributes
|
|
* @pos: loop counter, set to current attribute
|
|
* @nla: attribute containing the nested attributes
|
|
* @rem: initialized to len, holds bytes currently remaining in stream
|
|
*/
|
|
#define nla_for_each_nested(pos, nla, rem) \
|
|
nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
|
|
|
|
/**
|
|
* nla_is_last - Test if attribute is last in stream
|
|
* @nla: attribute to test
|
|
* @rem: bytes remaining in stream
|
|
*/
|
|
static inline bool nla_is_last(const struct nlattr *nla, int rem)
|
|
{
|
|
return nla->nla_len == rem;
|
|
}
|
|
|
|
#endif
|