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@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_len(const struct nlmsghdr *); 55 extern void * nlmsg_tail(const struct nlmsghdr *); 56 57 /* attribute access */ 58 extern struct nlattr * nlmsg_attrdata(const struct nlmsghdr *, int); 59 extern int nlmsg_attrlen(const struct nlmsghdr *, int); 60 61 /* message parsing */ 62 extern int nlmsg_valid_hdr(const struct nlmsghdr *, int); 63 extern int nlmsg_ok(const struct nlmsghdr *, int); 64 extern struct nlmsghdr * nlmsg_next(struct nlmsghdr *, int *); 65 extern int nlmsg_parse(struct nlmsghdr *, int, struct nlattr **, 66 int, struct nla_policy *); 67 extern struct nlattr * nlmsg_find_attr(struct nlmsghdr *, int, int); 68 extern int nlmsg_validate(struct nlmsghdr *, int, int, 69 struct nla_policy *); 70 71 extern struct nl_msg * nlmsg_alloc(void); 72 extern struct nl_msg * nlmsg_alloc_size(size_t); 73 extern struct nl_msg * nlmsg_alloc_simple(int, int); 74 extern void nlmsg_set_default_size(size_t); 75 extern struct nl_msg * nlmsg_inherit(struct nlmsghdr *); 76 extern struct nl_msg * nlmsg_convert(struct nlmsghdr *); 77 extern void * nlmsg_reserve(struct nl_msg *, size_t, int); 78 extern int nlmsg_append(struct nl_msg *, void *, size_t, int); 79 extern int nlmsg_expand(struct nl_msg *, size_t); 80 81 extern struct nlmsghdr * nlmsg_put(struct nl_msg *, uint32_t, uint32_t, 82 int, int, int); 83 extern struct nlmsghdr * nlmsg_hdr(struct nl_msg *); 84 extern void nlmsg_get(struct nl_msg *); 85 extern void nlmsg_free(struct nl_msg *); 86 87 /* attribute modification */ 88 extern void nlmsg_set_proto(struct nl_msg *, int); 89 extern int nlmsg_get_proto(struct nl_msg *); 90 extern size_t nlmsg_get_max_size(struct nl_msg *); 91 extern void nlmsg_set_src(struct nl_msg *, struct sockaddr_nl *); 92 extern struct sockaddr_nl *nlmsg_get_src(struct nl_msg *); 93 extern void nlmsg_set_dst(struct nl_msg *, struct sockaddr_nl *); 94 extern struct sockaddr_nl *nlmsg_get_dst(struct nl_msg *); 95 extern void nlmsg_set_creds(struct nl_msg *, struct ucred *); 96 extern struct ucred * nlmsg_get_creds(struct nl_msg *); 97 98 extern char * nl_nlmsgtype2str(int, char *, size_t); 99 extern int nl_str2nlmsgtype(const char *); 100 101 extern char * nl_nlmsg_flags2str(int, char *, size_t); 102 103 extern int nl_msg_parse(struct nl_msg *, 104 void (*cb)(struct nl_object *, void *), 105 void *); 106 107 extern void nl_msg_dump(struct nl_msg *, FILE *); 108 109 /** 110 * @name Iterators 111 * @{ 112 */ 113 114 /** 115 * @ingroup msg 116 * Iterate over a stream of attributes in a message 117 * @arg pos loop counter, set to current attribute 118 * @arg nlh netlink message header 119 * @arg hdrlen length of family header 120 * @arg rem initialized to len, holds bytes currently remaining in stream 121 */ 122 #define nlmsg_for_each_attr(pos, nlh, hdrlen, rem) \ 123 nla_for_each_attr(pos, nlmsg_attrdata(nlh, hdrlen), \ 124 nlmsg_attrlen(nlh, hdrlen), rem) 125 126 /** 127 * Iterate over a stream of messages 128 * @arg pos loop counter, set to current message 129 * @arg head head of message stream 130 * @arg len length of message stream 131 * @arg rem initialized to len, holds bytes currently remaining in stream 132 */ 133 #define nlmsg_for_each_msg(pos, head, len, rem) \ 134 for (pos = head, rem = len; \ 135 nlmsg_ok(pos, rem); \ 136 pos = nlmsg_next(pos, &(rem))) 137 138 /** @} */ 139 140 #ifdef __cplusplus 141 } 142 #endif 143 144 #endif 145