--- /dev/null
+/*
+ * 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
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