v4.19.13 snapshot.
diff --git a/include/net/netlink.h b/include/net/netlink.h
new file mode 100644
index 0000000..39e1d87
--- /dev/null
+++ b/include/net/netlink.h
@@ -0,0 +1,1423 @@
+/* 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 attributes
+ * 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_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 A 32-bit bitmap/bitselector attribute
+ * All other Minimum length of attribute payload
+ *
+ * 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