diff options
Diffstat (limited to 'include/net/netlink.h')
| -rw-r--r-- | include/net/netlink.h | 154 |
1 files changed, 138 insertions, 16 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index 640c26a90cf1..ce5cba19c393 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -35,12 +35,15 @@ * nlmsg_put() add a netlink message to an skb * nlmsg_put_answer() callback based nlmsg_put() * nlmsg_end() finanlize 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 @@ -62,6 +65,9 @@ * nlmsg_validate() validate netlink message incl. attrs * nlmsg_for_each_attr() loop over all attributes * + * Misc: + * nlmsg_report() report back to application? + * * ------------------------------------------------------------------------ * Attributes Interface * ------------------------------------------------------------------------ @@ -80,8 +86,10 @@ * struct nlattr netlink attribtue header * * Attribute Construction: - * nla_reserve(skb, type, len) reserve skb tailroom for an attribute + * 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 * * Attribute Construction for Basic Types: * nla_put_u8(skb, type, value) add u8 attribute to skb @@ -138,10 +146,13 @@ * 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 *========================================================================= */ @@ -158,6 +169,7 @@ enum { NLA_FLAG, NLA_MSECS, NLA_NESTED, + NLA_NUL_STRING, __NLA_TYPE_MAX, }; @@ -166,21 +178,37 @@ enum { /** * struct nla_policy - attribute validation policy * @type: Type of attribute or NLA_UNSPEC - * @minlen: Minimal length of payload required to be available + * @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 + * All other Exact length of attribute payload + * * Example: * static struct nla_policy my_policy[ATTR_MAX+1] __read_mostly = { * [ATTR_FOO] = { .type = NLA_U16 }, - * [ATTR_BAR] = { .type = NLA_STRING }, - * [ATTR_BAZ] = { .minlen = sizeof(struct mystruct) }, + * [ATTR_BAR] = { .type = NLA_STRING, len = BARSIZ }, + * [ATTR_BAZ] = { .len = sizeof(struct mystruct) }, * }; */ struct nla_policy { u16 type; - u16 minlen; + u16 len; +}; + +/** + * struct nl_info - netlink source information + * @nlh: Netlink message header of original request + * @pid: Netlink PID of requesting application + */ +struct nl_info { + struct nlmsghdr *nlh; + u32 pid; }; extern void netlink_run_queue(struct sock *sk, unsigned int *qlen, @@ -188,6 +216,9 @@ extern void netlink_run_queue(struct sock *sk, unsigned int *qlen, struct nlmsghdr *, int *)); extern void netlink_queue_skip(struct nlmsghdr *nlh, struct sk_buff *skb); +extern int nlmsg_notify(struct sock *sk, struct sk_buff *skb, + u32 pid, unsigned int group, int report, + gfp_t flags); extern int nla_validate(struct nlattr *head, int len, int maxtype, struct nla_policy *policy); @@ -203,12 +234,18 @@ extern int nla_memcmp(const struct nlattr *nla, const void *data, extern int nla_strcmp(const struct nlattr *nla, const char *str); extern struct nlattr * __nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); +extern void * __nla_reserve_nohdr(struct sk_buff *skb, int attrlen); extern struct nlattr * nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); +extern void * nla_reserve_nohdr(struct sk_buff *skb, int attrlen); extern void __nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data); +extern void __nla_put_nohdr(struct sk_buff *skb, int attrlen, + const void *data); extern int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data); +extern int nla_put_nohdr(struct sk_buff *skb, int attrlen, + const void *data); /************************************************************************** * Netlink Messages @@ -364,6 +401,17 @@ static inline int nlmsg_validate(struct nlmsghdr *nlh, int hdrlen, int maxtype, } /** + * 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(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 @@ -453,12 +501,13 @@ static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb, /** * nlmsg_new - Allocate a new netlink message * @size: maximum size of message + * @flags: the type of memory to allocate. * * Use NLMSG_GOODSIZE if size isn't know and you need a good default size. */ -static inline struct sk_buff *nlmsg_new(int size) +static inline struct sk_buff *nlmsg_new(int size, gfp_t flags) { - return alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); + return alloc_skb(size, flags); } /** @@ -480,6 +529,32 @@ static inline int nlmsg_end(struct sk_buff *skb, struct nlmsghdr *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; +} + +/** + * 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. Returns -1. + */ +static inline int nlmsg_trim(struct sk_buff *skb, void *mark) +{ + if (mark) + skb_trim(skb, (unsigned char *) mark - skb->data); + + return -1; +} + +/** * nlmsg_cancel - Cancel construction of a netlink message * @skb: socket buffer the message is stored in * @nlh: netlink message header @@ -489,9 +564,7 @@ static inline int nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh) */ static inline int nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh) { - skb_trim(skb, (unsigned char *) nlh - skb->data); - - return -1; + return nlmsg_trim(skb, nlh); } /** @@ -509,15 +582,16 @@ static inline void nlmsg_free(struct sk_buff *skb) * @skb: netlink message as socket buffer * @pid: own netlink pid 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 pid, unsigned int group) + u32 pid, unsigned int group, gfp_t flags) { int err; NETLINK_CB(skb).dst_group = group; - err = netlink_broadcast(sk, skb, pid, group, GFP_KERNEL); + err = netlink_broadcast(sk, skb, pid, group, flags); if (err > 0) err = 0; @@ -631,6 +705,18 @@ static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining) } /** + * 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(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 @@ -745,13 +831,16 @@ static inline int nla_put_msecs(struct sk_buff *skb, int attrtype, #define NLA_PUT_U32(skb, attrtype, value) \ NLA_PUT_TYPE(skb, u32, attrtype, value) +#define NLA_PUT_BE32(skb, attrtype, value) \ + NLA_PUT_TYPE(skb, __be32, attrtype, value) + #define NLA_PUT_U64(skb, attrtype, value) \ NLA_PUT_TYPE(skb, u64, attrtype, value) #define NLA_PUT_STRING(skb, attrtype, value) \ NLA_PUT(skb, attrtype, strlen(value) + 1, value) -#define NLA_PUT_FLAG(skb, attrtype, value) \ +#define NLA_PUT_FLAG(skb, attrtype) \ NLA_PUT(skb, attrtype, 0, NULL) #define NLA_PUT_MSECS(skb, attrtype, jiffies) \ @@ -767,6 +856,15 @@ static inline u32 nla_get_u32(struct nlattr *nla) } /** + * nla_get_be32 - return payload of __be32 attribute + * @nla: __be32 netlink attribute + */ +static inline __be32 nla_get_be32(struct nlattr *nla) +{ + return *(__be32 *) nla_data(nla); +} + +/** * nla_get_u16 - return payload of u16 attribute * @nla: u16 netlink attribute */ @@ -862,10 +960,25 @@ static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start) */ static inline int nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) { - if (start) - skb_trim(skb, (unsigned char *) start - skb->data); + return nlmsg_trim(skb, start); +} - return -1; +/** + * nla_validate_nested - Validate a stream of nested attributes + * @start: container attribute + * @maxtype: maximum attribute type to be expected + * @policy: validation policy + * + * 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(struct nlattr *start, int maxtype, + struct nla_policy *policy) +{ + return nla_validate(nla_data(start), nla_len(start), maxtype, policy); } /** @@ -880,4 +993,13 @@ static inline int nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) 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) + #endif |