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Diffstat (limited to 'package/libnl-tiny/src/include/netlink/msg.h')
-rw-r--r-- | package/libnl-tiny/src/include/netlink/msg.h | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/package/libnl-tiny/src/include/netlink/msg.h b/package/libnl-tiny/src/include/netlink/msg.h new file mode 100644 index 0000000..aedcb08 --- /dev/null +++ b/package/libnl-tiny/src/include/netlink/msg.h @@ -0,0 +1,308 @@ +/* + * netlink/msg.c Netlink Messages Interface + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation version 2.1 + * of the License. + * + * Copyright (c) 2003-2006 Thomas Graf <tgraf@suug.ch> + */ + +#ifndef NETLINK_MSG_H_ +#define NETLINK_MSG_H_ + +#include <netlink/netlink.h> +#include <netlink/object.h> + +#ifdef __cplusplus +extern "C" { +#endif + +struct nla_policy; + +#define NL_DONTPAD 0 + +/** + * @ingroup msg + * @brief + * Will cause the netlink pid to be set to the pid assigned to + * the netlink handle (socket) just before sending the message off. + * @note Requires the use of nl_send_auto_complete()! + */ +#define NL_AUTO_PID 0 + +/** + * @ingroup msg + * @brief + * May be used to refer to a sequence number which should be + * automatically set just before sending the message off. + * @note Requires the use of nl_send_auto_complete()! + */ +#define NL_AUTO_SEQ 0 + +#define NL_MSG_CRED_PRESENT 1 + +struct nl_msg +{ + int nm_protocol; + int nm_flags; + struct sockaddr_nl nm_src; + struct sockaddr_nl nm_dst; + struct ucred nm_creds; + struct nlmsghdr * nm_nlh; + size_t nm_size; + int nm_refcnt; +}; + + +struct nl_msg; +struct nl_tree; +struct ucred; + +/* message parsing */ +extern int nlmsg_ok(const struct nlmsghdr *, int); +extern struct nlmsghdr * nlmsg_next(struct nlmsghdr *, int *); +extern int nlmsg_parse(struct nlmsghdr *, int, struct nlattr **, + int, struct nla_policy *); +extern int nlmsg_validate(struct nlmsghdr *, int, int, + struct nla_policy *); + +extern struct nl_msg * nlmsg_alloc(void); +extern struct nl_msg * nlmsg_alloc_size(size_t); +extern struct nl_msg * nlmsg_alloc_simple(int, int); +extern void nlmsg_set_default_size(size_t); +extern struct nl_msg * nlmsg_inherit(struct nlmsghdr *); +extern struct nl_msg * nlmsg_convert(struct nlmsghdr *); +extern void * nlmsg_reserve(struct nl_msg *, size_t, int); +extern int nlmsg_append(struct nl_msg *, void *, size_t, int); + +extern struct nlmsghdr * nlmsg_put(struct nl_msg *, uint32_t, uint32_t, + int, int, int); +extern void nlmsg_free(struct nl_msg *); + +extern int nl_msg_parse(struct nl_msg *, + void (*cb)(struct nl_object *, void *), + void *); + +extern void nl_msg_dump(struct nl_msg *, FILE *); + +/** + * length of netlink message not including padding + * @arg payload length of message payload + */ +static inline int nlmsg_msg_size(int payload) +{ + return NLMSG_HDRLEN + payload; +} + +/** + * length of netlink message including padding + * @arg payload length of message payload + */ +static inline int nlmsg_total_size(int payload) +{ + return NLMSG_ALIGN(nlmsg_msg_size(payload)); +} + +/** + * length of padding at the message's tail + * @arg payload length of message payload + */ +static inline int nlmsg_padlen(int payload) +{ + return nlmsg_total_size(payload) - nlmsg_msg_size(payload); +} + +/** + * head of message payload + * @arg nlh netlink messsage header + */ +static inline void *nlmsg_data(const struct nlmsghdr *nlh) +{ + return (unsigned char *) nlh + NLMSG_HDRLEN; +} + +static inline void *nlmsg_tail(const struct nlmsghdr *nlh) +{ + return (unsigned char *) nlh + NLMSG_ALIGN(nlh->nlmsg_len); +} + +/** + * length of message payload + * @arg nlh netlink message header + */ +static inline int nlmsg_len(const struct nlmsghdr *nlh) +{ + return nlh->nlmsg_len - NLMSG_HDRLEN; +} + +/** + * head of attributes data + * @arg nlh netlink message header + * @arg 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)); +} + +/** + * length of attributes data + * @arg nlh netlink message header + * @arg hdrlen length of family specific header + */ +static inline int nlmsg_attrlen(const struct nlmsghdr *nlh, int hdrlen) +{ + return nlmsg_len(nlh) - NLMSG_ALIGN(hdrlen); +} + +static inline int nlmsg_valid_hdr(const struct nlmsghdr *nlh, int hdrlen) +{ + if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) + return 0; + + return 1; +} + + +static inline void nlmsg_set_proto(struct nl_msg *msg, int protocol) +{ + msg->nm_protocol = protocol; +} + +static inline int nlmsg_get_proto(struct nl_msg *msg) +{ + return msg->nm_protocol; +} + +static inline size_t nlmsg_get_max_size(struct nl_msg *msg) +{ + return msg->nm_size; +} + +static inline void nlmsg_set_src(struct nl_msg *msg, struct sockaddr_nl *addr) +{ + memcpy(&msg->nm_src, addr, sizeof(*addr)); +} + +static inline struct sockaddr_nl *nlmsg_get_src(struct nl_msg *msg) +{ + return &msg->nm_src; +} + +static inline void nlmsg_set_dst(struct nl_msg *msg, struct sockaddr_nl *addr) +{ + memcpy(&msg->nm_dst, addr, sizeof(*addr)); +} + +static inline struct sockaddr_nl *nlmsg_get_dst(struct nl_msg *msg) +{ + return &msg->nm_dst; +} + +static inline void nlmsg_set_creds(struct nl_msg *msg, struct ucred *creds) +{ + memcpy(&msg->nm_creds, creds, sizeof(*creds)); + msg->nm_flags |= NL_MSG_CRED_PRESENT; +} + +static inline struct ucred *nlmsg_get_creds(struct nl_msg *msg) +{ + if (msg->nm_flags & NL_MSG_CRED_PRESENT) + return &msg->nm_creds; + return NULL; +} + +/** + * Return actual netlink message + * @arg n netlink message + * + * Returns the actual netlink message casted to the type of the netlink + * message header. + * + * @return A pointer to the netlink message. + */ +static inline struct nlmsghdr *nlmsg_hdr(struct nl_msg *n) +{ + return n->nm_nlh; +} + +/** + * Acquire a reference on a netlink message + * @arg msg message to acquire reference from + */ +static inline void nlmsg_get(struct nl_msg *msg) +{ + msg->nm_refcnt++; +} + +/** + * Expand maximum payload size of a netlink message + * @arg n Netlink message. + * @arg newlen New maximum payload size. + * + * Reallocates the payload section of a netlink message and increases + * the maximum payload size of the message. + * + * @note Any pointers pointing to old payload block will be stale and + * need to be refetched. Therfore, do not expand while constructing + * nested attributes or while reserved data blocks are held. + * + * @return 0 on success or a negative error code. + */ +static inline int nlmsg_expand(struct nl_msg *n, size_t newlen) +{ + void *tmp; + + if (newlen <= n->nm_size) + return -NLE_INVAL; + + tmp = realloc(n->nm_nlh, newlen); + if (tmp == NULL) + return -NLE_NOMEM; + + n->nm_nlh = tmp; + n->nm_size = newlen; + + return 0; +} + + +/** + * @name Iterators + * @{ + */ + +/** + * @ingroup msg + * Iterate over a stream of attributes in a message + * @arg pos loop counter, set to current attribute + * @arg nlh netlink message header + * @arg hdrlen length of family header + * @arg 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) + +/** + * Iterate over a stream of messages + * @arg pos loop counter, set to current message + * @arg head head of message stream + * @arg len length of message stream + * @arg 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))) + +/** @} */ + +#ifdef __cplusplus +} +#endif + +#endif |