1 /* 2 * netlink/msg.c Netlink Messages Interface 3 * 4 * This library is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Lesser General Public 6 * License as published by the Free Software Foundation version 2.1 7 * of the License. 8 * 9 * Copyright (c) 2003-2006 Thomas Graf <tgraf (at) suug.ch> 10 */ 11 12 #ifndef NETLINK_MSG_H_ 13 #define NETLINK_MSG_H_ 14 15 #include <netlink/netlink.h> 16 #include <netlink/object.h> 17 #include <netlink/attr.h> 18 19 #ifdef __cplusplus 20 extern "C" { 21 #endif 22 23 #define NL_DONTPAD 0 24 25 /** 26 * @ingroup msg 27 * @brief 28 * Will cause the netlink pid to be set to the pid assigned to 29 * the netlink handle (socket) just before sending the message off. 30 * @note Requires the use of nl_send_auto_complete()! 31 */ 32 #define NL_AUTO_PID 0 33 34 /** 35 * @ingroup msg 36 * @brief 37 * May be used to refer to a sequence number which should be 38 * automatically set just before sending the message off. 39 * @note Requires the use of nl_send_auto_complete()! 40 */ 41 #define NL_AUTO_SEQ 0 42 43 struct nl_msg; 44 struct nl_tree; 45 struct ucred; 46 47 /* size calculations */ 48 extern int nlmsg_msg_size(int); 49 extern int nlmsg_total_size(int); 50 extern int nlmsg_padlen(int); 51 52 /* payload access */ 53 extern void * nlmsg_data(const struct nlmsghdr *); 54 extern int nlmsg_datalen(const struct nlmsghdr *); 55 extern int nlmsg_len(const struct nlmsghdr *); 56 extern void * nlmsg_tail(const struct nlmsghdr *); 57 58 /* attribute access */ 59 extern struct nlattr * nlmsg_attrdata(const struct nlmsghdr *, int); 60 extern int nlmsg_attrlen(const struct nlmsghdr *, int); 61 62 /* message parsing */ 63 extern int nlmsg_valid_hdr(const struct nlmsghdr *, int); 64 extern int nlmsg_ok(const struct nlmsghdr *, int); 65 extern struct nlmsghdr * nlmsg_next(struct nlmsghdr *, int *); 66 extern int nlmsg_parse(struct nlmsghdr *, int, struct nlattr **, 67 int, struct nla_policy *); 68 extern struct nlattr * nlmsg_find_attr(struct nlmsghdr *, int, int); 69 extern int nlmsg_validate(struct nlmsghdr *, int, int, 70 struct nla_policy *); 71 72 extern struct nl_msg * nlmsg_alloc(void); 73 extern struct nl_msg * nlmsg_alloc_size(size_t); 74 extern struct nl_msg * nlmsg_alloc_simple(int, int); 75 extern void nlmsg_set_default_size(size_t); 76 extern struct nl_msg * nlmsg_inherit(struct nlmsghdr *); 77 extern struct nl_msg * nlmsg_convert(struct nlmsghdr *); 78 extern void * nlmsg_reserve(struct nl_msg *, size_t, int); 79 extern int nlmsg_append(struct nl_msg *, void *, size_t, int); 80 extern int nlmsg_expand(struct nl_msg *, size_t); 81 82 extern struct nlmsghdr * nlmsg_put(struct nl_msg *, uint32_t, uint32_t, 83 int, int, int); 84 extern struct nlmsghdr * nlmsg_hdr(struct nl_msg *); 85 extern void nlmsg_get(struct nl_msg *); 86 extern void nlmsg_free(struct nl_msg *); 87 88 /* attribute modification */ 89 extern void nlmsg_set_proto(struct nl_msg *, int); 90 extern int nlmsg_get_proto(struct nl_msg *); 91 extern size_t nlmsg_get_max_size(struct nl_msg *); 92 extern void nlmsg_set_src(struct nl_msg *, struct sockaddr_nl *); 93 extern struct sockaddr_nl *nlmsg_get_src(struct nl_msg *); 94 extern void nlmsg_set_dst(struct nl_msg *, struct sockaddr_nl *); 95 extern struct sockaddr_nl *nlmsg_get_dst(struct nl_msg *); 96 extern void nlmsg_set_creds(struct nl_msg *, struct ucred *); 97 extern struct ucred * nlmsg_get_creds(struct nl_msg *); 98 99 extern char * nl_nlmsgtype2str(int, char *, size_t); 100 extern int nl_str2nlmsgtype(const char *); 101 102 extern char * nl_nlmsg_flags2str(int, char *, size_t); 103 104 extern int nl_msg_parse(struct nl_msg *, 105 void (*cb)(struct nl_object *, void *), 106 void *); 107 108 extern void nl_msg_dump(struct nl_msg *, FILE *); 109 110 /** 111 * @name Iterators 112 * @{ 113 */ 114 115 /** 116 * @ingroup msg 117 * Iterate over a stream of attributes in a message 118 * @arg pos loop counter, set to current attribute 119 * @arg nlh netlink message header 120 * @arg hdrlen length of family header 121 * @arg rem initialized to len, holds bytes currently remaining in stream 122 */ 123 #define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \ 124 nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \ 125 nlmsg_attrlen(nlh, hdrlen), rem) 126 127 /** 128 * Iterate over a stream of messages 129 * @arg pos loop counter, set to current message 130 * @arg head head of message stream 131 * @arg len length of message stream 132 * @arg rem initialized to len, holds bytes currently remaining in stream 133 */ 134 #define nlmsg_for_each_msg(pos, head, len, rem) \ 135 for (pos = head, rem = len; \ 136 nlmsg_ok(pos, rem); \ 137 pos = nlmsg_next(pos, &(rem))) 138 139 /** @} */ 140 141 #ifdef __cplusplus 142 } 143 #endif 144 145 #endif 146