/* * net/tipc/msg.c: TIPC message header routines * * Copyright (c) 2000-2006, 2014-2015, Ericsson AB * Copyright (c) 2005, 2010-2011, Wind River Systems * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the names of the copyright holders nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include <net/sock.h> #include "core.h" #include "msg.h" #include "addr.h" #include "name_table.h" #include "crypto.h" #define BUF_ALIGN(x) … #define MAX_FORWARD_SIZE … #ifdef CONFIG_TIPC_CRYPTO #define BUF_HEADROOM … #define BUF_OVERHEAD … #else #define BUF_HEADROOM … #define BUF_OVERHEAD … #endif const int one_page_mtu = …; /** * tipc_buf_acquire - creates a TIPC message buffer * @size: message size (including TIPC header) * @gfp: memory allocation flags * * Return: a new buffer with data pointers set to the specified size. * * NOTE: * Headroom is reserved to allow prepending of a data link header. * There may also be unrequested tailroom present at the buffer's end. */ struct sk_buff *tipc_buf_acquire(u32 size, gfp_t gfp) { … } void tipc_msg_init(u32 own_node, struct tipc_msg *m, u32 user, u32 type, u32 hsize, u32 dnode) { … } struct sk_buff *tipc_msg_create(uint user, uint type, uint hdr_sz, uint data_sz, u32 dnode, u32 onode, u32 dport, u32 oport, int errcode) { … } /* tipc_buf_append(): Append a buffer to the fragment list of another buffer * @*headbuf: in: NULL for first frag, otherwise value returned from prev call * out: set when successful non-complete reassembly, otherwise NULL * @*buf: in: the buffer to append. Always defined * out: head buf after successful complete reassembly, otherwise NULL * Returns 1 when reassembly complete, otherwise 0 */ int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf) { … } /** * tipc_msg_append(): Append data to tail of an existing buffer queue * @_hdr: header to be used * @m: the data to be appended * @mss: max allowable size of buffer * @dlen: size of data to be appended * @txq: queue to append to * * Return: the number of 1k blocks appended or errno value */ int tipc_msg_append(struct tipc_msg *_hdr, struct msghdr *m, int dlen, int mss, struct sk_buff_head *txq) { … } /* tipc_msg_validate - validate basic format of received message * * This routine ensures a TIPC message has an acceptable header, and at least * as much data as the header indicates it should. The routine also ensures * that the entire message header is stored in the main fragment of the message * buffer, to simplify future access to message header fields. * * Note: Having extra info present in the message header or data areas is OK. * TIPC will ignore the excess, under the assumption that it is optional info * introduced by a later release of the protocol. */ bool tipc_msg_validate(struct sk_buff **_skb) { … } /** * tipc_msg_fragment - build a fragment skb list for TIPC message * * @skb: TIPC message skb * @hdr: internal msg header to be put on the top of the fragments * @pktmax: max size of a fragment incl. the header * @frags: returned fragment skb list * * Return: 0 if the fragmentation is successful, otherwise: -EINVAL * or -ENOMEM */ int tipc_msg_fragment(struct sk_buff *skb, const struct tipc_msg *hdr, int pktmax, struct sk_buff_head *frags) { … } /** * tipc_msg_build - create buffer chain containing specified header and data * @mhdr: Message header, to be prepended to data * @m: User message * @offset: buffer offset for fragmented messages (FIXME) * @dsz: Total length of user data * @pktmax: Max packet size that can be used * @list: Buffer or chain of buffers to be returned to caller * * Note that the recursive call we are making here is safe, since it can * logically go only one further level down. * * Return: message data size or errno: -ENOMEM, -EFAULT */ int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m, int offset, int dsz, int pktmax, struct sk_buff_head *list) { … } /** * tipc_msg_bundle - Append contents of a buffer to tail of an existing one * @bskb: the bundle buffer to append to * @msg: message to be appended * @max: max allowable size for the bundle buffer * * Return: "true" if bundling has been performed, otherwise "false" */ static bool tipc_msg_bundle(struct sk_buff *bskb, struct tipc_msg *msg, u32 max) { … } /** * tipc_msg_try_bundle - Try to bundle a new message to the last one * @tskb: the last/target message to which the new one will be appended * @skb: the new message skb pointer * @mss: max message size (header inclusive) * @dnode: destination node for the message * @new_bundle: if this call made a new bundle or not * * Return: "true" if the new message skb is potential for bundling this time or * later, in the case a bundling has been done this time, the skb is consumed * (the skb pointer = NULL). * Otherwise, "false" if the skb cannot be bundled at all. */ bool tipc_msg_try_bundle(struct sk_buff *tskb, struct sk_buff **skb, u32 mss, u32 dnode, bool *new_bundle) { … } /** * tipc_msg_extract(): extract bundled inner packet from buffer * @skb: buffer to be extracted from. * @iskb: extracted inner buffer, to be returned * @pos: position in outer message of msg to be extracted. * Returns position of next msg. * Consumes outer buffer when last packet extracted * Return: true when there is an extracted buffer, otherwise false */ bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos) { … } /** * tipc_msg_reverse(): swap source and destination addresses and add error code * @own_node: originating node id for reversed message * @skb: buffer containing message to be reversed; will be consumed * @err: error code to be set in message, if any * Replaces consumed buffer with new one when successful * Return: true if success, otherwise false */ bool tipc_msg_reverse(u32 own_node, struct sk_buff **skb, int err) { … } bool tipc_msg_skb_clone(struct sk_buff_head *msg, struct sk_buff_head *cpy) { … } /** * tipc_msg_lookup_dest(): try to find new destination for named message * @net: pointer to associated network namespace * @skb: the buffer containing the message. * @err: error code to be used by caller if lookup fails * Does not consume buffer * Return: true if a destination is found, false otherwise */ bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err) { … } /* tipc_msg_assemble() - assemble chain of fragments into one message */ bool tipc_msg_assemble(struct sk_buff_head *list) { … } /* tipc_msg_reassemble() - clone a buffer chain of fragments and * reassemble the clones into one message */ bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq) { … } bool tipc_msg_pskb_copy(u32 dst, struct sk_buff_head *msg, struct sk_buff_head *cpy) { … } /* tipc_skb_queue_sorted(); sort pkt into list according to sequence number * @list: list to be appended to * @seqno: sequence number of buffer to add * @skb: buffer to add */ bool __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno, struct sk_buff *skb) { … } void tipc_skb_reject(struct net *net, int err, struct sk_buff *skb, struct sk_buff_head *xmitq) { … }