| /* |
| * 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 MAX_FORWARD_SIZE 1024 |
| #ifdef CONFIG_TIPC_CRYPTO |
| #define BUF_HEADROOM ALIGN(((LL_MAX_HEADER + 48) + EHDR_MAX_SIZE), 16) |
| #define BUF_TAILROOM (TIPC_AES_GCM_TAG_SIZE) |
| #else |
| #define BUF_HEADROOM (LL_MAX_HEADER + 48) |
| #define BUF_TAILROOM 16 |
| #endif |
| |
| static unsigned int align(unsigned int i) |
| { |
| return (i + 3) & ~3u; |
| } |
| |
| /** |
| * tipc_buf_acquire - creates a TIPC message buffer |
| * @size: message size (including TIPC header) |
| * |
| * Returns 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) |
| { |
| struct sk_buff *skb; |
| #ifdef CONFIG_TIPC_CRYPTO |
| unsigned int buf_size = (BUF_HEADROOM + size + BUF_TAILROOM + 3) & ~3u; |
| #else |
| unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u; |
| #endif |
| |
| skb = alloc_skb_fclone(buf_size, gfp); |
| if (skb) { |
| skb_reserve(skb, BUF_HEADROOM); |
| skb_put(skb, size); |
| skb->next = NULL; |
| } |
| return skb; |
| } |
| |
| void tipc_msg_init(u32 own_node, struct tipc_msg *m, u32 user, u32 type, |
| u32 hsize, u32 dnode) |
| { |
| memset(m, 0, hsize); |
| msg_set_version(m); |
| msg_set_user(m, user); |
| msg_set_hdr_sz(m, hsize); |
| msg_set_size(m, hsize); |
| msg_set_prevnode(m, own_node); |
| msg_set_type(m, type); |
| if (hsize > SHORT_H_SIZE) { |
| msg_set_orignode(m, own_node); |
| msg_set_destnode(m, 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) |
| { |
| struct tipc_msg *msg; |
| struct sk_buff *buf; |
| |
| buf = tipc_buf_acquire(hdr_sz + data_sz, GFP_ATOMIC); |
| if (unlikely(!buf)) |
| return NULL; |
| |
| msg = buf_msg(buf); |
| tipc_msg_init(onode, msg, user, type, hdr_sz, dnode); |
| msg_set_size(msg, hdr_sz + data_sz); |
| msg_set_origport(msg, oport); |
| msg_set_destport(msg, dport); |
| msg_set_errcode(msg, errcode); |
| if (hdr_sz > SHORT_H_SIZE) { |
| msg_set_orignode(msg, onode); |
| msg_set_destnode(msg, dnode); |
| } |
| return buf; |
| } |
| |
| /* 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) |
| { |
| struct sk_buff *head = *headbuf; |
| struct sk_buff *frag = *buf; |
| struct sk_buff *tail = NULL; |
| struct tipc_msg *msg; |
| u32 fragid; |
| int delta; |
| bool headstolen; |
| |
| if (!frag) |
| goto err; |
| |
| msg = buf_msg(frag); |
| fragid = msg_type(msg); |
| frag->next = NULL; |
| skb_pull(frag, msg_hdr_sz(msg)); |
| |
| if (fragid == FIRST_FRAGMENT) { |
| if (unlikely(head)) |
| goto err; |
| frag = skb_unshare(frag, GFP_ATOMIC); |
| if (unlikely(!frag)) |
| goto err; |
| head = *headbuf = frag; |
| *buf = NULL; |
| TIPC_SKB_CB(head)->tail = NULL; |
| if (skb_is_nonlinear(head)) { |
| skb_walk_frags(head, tail) { |
| TIPC_SKB_CB(head)->tail = tail; |
| } |
| } else { |
| skb_frag_list_init(head); |
| } |
| return 0; |
| } |
| |
| if (!head) |
| goto err; |
| |
| if (skb_try_coalesce(head, frag, &headstolen, &delta)) { |
| kfree_skb_partial(frag, headstolen); |
| } else { |
| tail = TIPC_SKB_CB(head)->tail; |
| if (!skb_has_frag_list(head)) |
| skb_shinfo(head)->frag_list = frag; |
| else |
| tail->next = frag; |
| head->truesize += frag->truesize; |
| head->data_len += frag->len; |
| head->len += frag->len; |
| TIPC_SKB_CB(head)->tail = frag; |
| } |
| |
| if (fragid == LAST_FRAGMENT) { |
| TIPC_SKB_CB(head)->validated = 0; |
| if (unlikely(!tipc_msg_validate(&head))) |
| goto err; |
| *buf = head; |
| TIPC_SKB_CB(head)->tail = NULL; |
| *headbuf = NULL; |
| return 1; |
| } |
| *buf = NULL; |
| return 0; |
| err: |
| kfree_skb(*buf); |
| kfree_skb(*headbuf); |
| *buf = *headbuf = NULL; |
| return 0; |
| } |
| |
| /** |
| * 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 appand to |
| * Returns the number og 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) |
| { |
| struct sk_buff *skb; |
| int accounted, total, curr; |
| int mlen, cpy, rem = dlen; |
| struct tipc_msg *hdr; |
| |
| skb = skb_peek_tail(txq); |
| accounted = skb ? msg_blocks(buf_msg(skb)) : 0; |
| total = accounted; |
| |
| do { |
| if (!skb || skb->len >= mss) { |
| skb = tipc_buf_acquire(mss, GFP_KERNEL); |
| if (unlikely(!skb)) |
| return -ENOMEM; |
| skb_orphan(skb); |
| skb_trim(skb, MIN_H_SIZE); |
| hdr = buf_msg(skb); |
| skb_copy_to_linear_data(skb, _hdr, MIN_H_SIZE); |
| msg_set_hdr_sz(hdr, MIN_H_SIZE); |
| msg_set_size(hdr, MIN_H_SIZE); |
| __skb_queue_tail(txq, skb); |
| total += 1; |
| } |
| hdr = buf_msg(skb); |
| curr = msg_blocks(hdr); |
| mlen = msg_size(hdr); |
| cpy = min_t(size_t, rem, mss - mlen); |
| if (cpy != copy_from_iter(skb->data + mlen, cpy, &m->msg_iter)) |
| return -EFAULT; |
| msg_set_size(hdr, mlen + cpy); |
| skb_put(skb, cpy); |
| rem -= cpy; |
| total += msg_blocks(hdr) - curr; |
| } while (rem > 0); |
| return total - accounted; |
| } |
| |
| /* 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) |
| { |
| struct sk_buff *skb = *_skb; |
| struct tipc_msg *hdr; |
| int msz, hsz; |
| |
| /* Ensure that flow control ratio condition is satisfied */ |
| if (unlikely(skb->truesize / buf_roundup_len(skb) >= 4)) { |
| skb = skb_copy_expand(skb, BUF_HEADROOM, 0, GFP_ATOMIC); |
| if (!skb) |
| return false; |
| kfree_skb(*_skb); |
| *_skb = skb; |
| } |
| |
| if (unlikely(TIPC_SKB_CB(skb)->validated)) |
| return true; |
| |
| if (unlikely(!pskb_may_pull(skb, MIN_H_SIZE))) |
| return false; |
| |
| hsz = msg_hdr_sz(buf_msg(skb)); |
| if (unlikely(hsz < MIN_H_SIZE) || (hsz > MAX_H_SIZE)) |
| return false; |
| if (unlikely(!pskb_may_pull(skb, hsz))) |
| return false; |
| |
| hdr = buf_msg(skb); |
| if (unlikely(msg_version(hdr) != TIPC_VERSION)) |
| return false; |
| |
| msz = msg_size(hdr); |
| if (unlikely(msz < hsz)) |
| return false; |
| if (unlikely((msz - hsz) > TIPC_MAX_USER_MSG_SIZE)) |
| return false; |
| if (unlikely(skb->len < msz)) |
| return false; |
| |
| TIPC_SKB_CB(skb)->validated = 1; |
| return true; |
| } |
| |
| /** |
| * 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 |
| * |
| * Returns 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) |
| { |
| int pktno, nof_fragms, dsz, dmax, eat; |
| struct tipc_msg *_hdr; |
| struct sk_buff *_skb; |
| u8 *data; |
| |
| /* Non-linear buffer? */ |
| if (skb_linearize(skb)) |
| return -ENOMEM; |
| |
| data = (u8 *)skb->data; |
| dsz = msg_size(buf_msg(skb)); |
| dmax = pktmax - INT_H_SIZE; |
| if (dsz <= dmax || !dmax) |
| return -EINVAL; |
| |
| nof_fragms = dsz / dmax + 1; |
| for (pktno = 1; pktno <= nof_fragms; pktno++) { |
| if (pktno < nof_fragms) |
| eat = dmax; |
| else |
| eat = dsz % dmax; |
| /* Allocate a new fragment */ |
| _skb = tipc_buf_acquire(INT_H_SIZE + eat, GFP_ATOMIC); |
| if (!_skb) |
| goto error; |
| skb_orphan(_skb); |
| __skb_queue_tail(frags, _skb); |
| /* Copy header & data to the fragment */ |
| skb_copy_to_linear_data(_skb, hdr, INT_H_SIZE); |
| skb_copy_to_linear_data_offset(_skb, INT_H_SIZE, data, eat); |
| data += eat; |
| /* Update the fragment's header */ |
| _hdr = buf_msg(_skb); |
| msg_set_fragm_no(_hdr, pktno); |
| msg_set_nof_fragms(_hdr, nof_fragms); |
| msg_set_size(_hdr, INT_H_SIZE + eat); |
| } |
| return 0; |
| |
| error: |
| __skb_queue_purge(frags); |
| __skb_queue_head_init(frags); |
| return -ENOMEM; |
| } |
| |
| /** |
| * tipc_msg_build - create buffer chain containing specified header and data |
| * @mhdr: Message header, to be prepended to data |
| * @m: User message |
| * @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. |
| * |
| * Returns 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) |
| { |
| int mhsz = msg_hdr_sz(mhdr); |
| struct tipc_msg pkthdr; |
| int msz = mhsz + dsz; |
| int pktrem = pktmax; |
| struct sk_buff *skb; |
| int drem = dsz; |
| int pktno = 1; |
| char *pktpos; |
| int pktsz; |
| int rc; |
| |
| msg_set_size(mhdr, msz); |
| |
| /* No fragmentation needed? */ |
| if (likely(msz <= pktmax)) { |
| skb = tipc_buf_acquire(msz, GFP_KERNEL); |
| |
| /* Fall back to smaller MTU if node local message */ |
| if (unlikely(!skb)) { |
| if (pktmax != MAX_MSG_SIZE) |
| return -ENOMEM; |
| rc = tipc_msg_build(mhdr, m, offset, dsz, FB_MTU, list); |
| if (rc != dsz) |
| return rc; |
| if (tipc_msg_assemble(list)) |
| return dsz; |
| return -ENOMEM; |
| } |
| skb_orphan(skb); |
| __skb_queue_tail(list, skb); |
| skb_copy_to_linear_data(skb, mhdr, mhsz); |
| pktpos = skb->data + mhsz; |
| if (copy_from_iter_full(pktpos, dsz, &m->msg_iter)) |
| return dsz; |
| rc = -EFAULT; |
| goto error; |
| } |
| |
| /* Prepare reusable fragment header */ |
| tipc_msg_init(msg_prevnode(mhdr), &pkthdr, MSG_FRAGMENTER, |
| FIRST_FRAGMENT, INT_H_SIZE, msg_destnode(mhdr)); |
| msg_set_size(&pkthdr, pktmax); |
| msg_set_fragm_no(&pkthdr, pktno); |
| msg_set_importance(&pkthdr, msg_importance(mhdr)); |
| |
| /* Prepare first fragment */ |
| skb = tipc_buf_acquire(pktmax, GFP_KERNEL); |
| if (!skb) |
| return -ENOMEM; |
| skb_orphan(skb); |
| __skb_queue_tail(list, skb); |
| pktpos = skb->data; |
| skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE); |
| pktpos += INT_H_SIZE; |
| pktrem -= INT_H_SIZE; |
| skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz); |
| pktpos += mhsz; |
| pktrem -= mhsz; |
| |
| do { |
| if (drem < pktrem) |
| pktrem = drem; |
| |
| if (!copy_from_iter_full(pktpos, pktrem, &m->msg_iter)) { |
| rc = -EFAULT; |
| goto error; |
| } |
| drem -= pktrem; |
| |
| if (!drem) |
| break; |
| |
| /* Prepare new fragment: */ |
| if (drem < (pktmax - INT_H_SIZE)) |
| pktsz = drem + INT_H_SIZE; |
| else |
| pktsz = pktmax; |
| skb = tipc_buf_acquire(pktsz, GFP_KERNEL); |
| if (!skb) { |
| rc = -ENOMEM; |
| goto error; |
| } |
| skb_orphan(skb); |
| __skb_queue_tail(list, skb); |
| msg_set_type(&pkthdr, FRAGMENT); |
| msg_set_size(&pkthdr, pktsz); |
| msg_set_fragm_no(&pkthdr, ++pktno); |
| skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE); |
| pktpos = skb->data + INT_H_SIZE; |
| pktrem = pktsz - INT_H_SIZE; |
| |
| } while (1); |
| msg_set_type(buf_msg(skb), LAST_FRAGMENT); |
| return dsz; |
| error: |
| __skb_queue_purge(list); |
| __skb_queue_head_init(list); |
| return rc; |
| } |
| |
| /** |
| * 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 |
| * |
| * Returns "true" if bundling has been performed, otherwise "false" |
| */ |
| static bool tipc_msg_bundle(struct sk_buff *bskb, struct tipc_msg *msg, |
| u32 max) |
| { |
| struct tipc_msg *bmsg = buf_msg(bskb); |
| u32 msz, bsz, offset, pad; |
| |
| msz = msg_size(msg); |
| bsz = msg_size(bmsg); |
| offset = align(bsz); |
| pad = offset - bsz; |
| |
| if (unlikely(skb_tailroom(bskb) < (pad + msz))) |
| return false; |
| if (unlikely(max < (offset + msz))) |
| return false; |
| |
| skb_put(bskb, pad + msz); |
| skb_copy_to_linear_data_offset(bskb, offset, msg, msz); |
| msg_set_size(bmsg, offset + msz); |
| msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1); |
| return true; |
| } |
| |
| /** |
| * 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) |
| { |
| struct tipc_msg *msg, *inner, *outer; |
| u32 tsz; |
| |
| /* First, check if the new buffer is suitable for bundling */ |
| msg = buf_msg(*skb); |
| if (msg_user(msg) == MSG_FRAGMENTER) |
| return false; |
| if (msg_user(msg) == TUNNEL_PROTOCOL) |
| return false; |
| if (msg_user(msg) == BCAST_PROTOCOL) |
| return false; |
| if (mss <= INT_H_SIZE + msg_size(msg)) |
| return false; |
| |
| /* Ok, but the last/target buffer can be empty? */ |
| if (unlikely(!tskb)) |
| return true; |
| |
| /* Is it a bundle already? Try to bundle the new message to it */ |
| if (msg_user(buf_msg(tskb)) == MSG_BUNDLER) { |
| *new_bundle = false; |
| goto bundle; |
| } |
| |
| /* Make a new bundle of the two messages if possible */ |
| tsz = msg_size(buf_msg(tskb)); |
| if (unlikely(mss < align(INT_H_SIZE + tsz) + msg_size(msg))) |
| return true; |
| if (unlikely(pskb_expand_head(tskb, INT_H_SIZE, mss - tsz - INT_H_SIZE, |
| GFP_ATOMIC))) |
| return true; |
| inner = buf_msg(tskb); |
| skb_push(tskb, INT_H_SIZE); |
| outer = buf_msg(tskb); |
| tipc_msg_init(msg_prevnode(inner), outer, MSG_BUNDLER, 0, INT_H_SIZE, |
| dnode); |
| msg_set_importance(outer, msg_importance(inner)); |
| msg_set_size(outer, INT_H_SIZE + tsz); |
| msg_set_msgcnt(outer, 1); |
| *new_bundle = true; |
| |
| bundle: |
| if (likely(tipc_msg_bundle(tskb, msg, mss))) { |
| consume_skb(*skb); |
| *skb = NULL; |
| } |
| return true; |
| } |
| |
| /** |
| * 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 |
| * Returns true when when there is an extracted buffer, otherwise false |
| */ |
| bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos) |
| { |
| struct tipc_msg *hdr, *ihdr; |
| int imsz; |
| |
| *iskb = NULL; |
| if (unlikely(skb_linearize(skb))) |
| goto none; |
| |
| hdr = buf_msg(skb); |
| if (unlikely(*pos > (msg_data_sz(hdr) - MIN_H_SIZE))) |
| goto none; |
| |
| ihdr = (struct tipc_msg *)(msg_data(hdr) + *pos); |
| imsz = msg_size(ihdr); |
| |
| if ((*pos + imsz) > msg_data_sz(hdr)) |
| goto none; |
| |
| *iskb = tipc_buf_acquire(imsz, GFP_ATOMIC); |
| if (!*iskb) |
| goto none; |
| |
| skb_copy_to_linear_data(*iskb, ihdr, imsz); |
| if (unlikely(!tipc_msg_validate(iskb))) |
| goto none; |
| |
| *pos += align(imsz); |
| return true; |
| none: |
| kfree_skb(skb); |
| kfree_skb(*iskb); |
| *iskb = NULL; |
| return false; |
| } |
| |
| /** |
| * 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 |
| * Returns true if success, otherwise false |
| */ |
| bool tipc_msg_reverse(u32 own_node, struct sk_buff **skb, int err) |
| { |
| struct sk_buff *_skb = *skb; |
| struct tipc_msg *_hdr, *hdr; |
| int hlen, dlen; |
| |
| if (skb_linearize(_skb)) |
| goto exit; |
| _hdr = buf_msg(_skb); |
| dlen = min_t(uint, msg_data_sz(_hdr), MAX_FORWARD_SIZE); |
| hlen = msg_hdr_sz(_hdr); |
| |
| if (msg_dest_droppable(_hdr)) |
| goto exit; |
| if (msg_errcode(_hdr)) |
| goto exit; |
| |
| /* Never return SHORT header */ |
| if (hlen == SHORT_H_SIZE) |
| hlen = BASIC_H_SIZE; |
| |
| /* Don't return data along with SYN+, - sender has a clone */ |
| if (msg_is_syn(_hdr) && err == TIPC_ERR_OVERLOAD) |
| dlen = 0; |
| |
| /* Allocate new buffer to return */ |
| *skb = tipc_buf_acquire(hlen + dlen, GFP_ATOMIC); |
| if (!*skb) |
| goto exit; |
| memcpy((*skb)->data, _skb->data, msg_hdr_sz(_hdr)); |
| memcpy((*skb)->data + hlen, msg_data(_hdr), dlen); |
| |
| /* Build reverse header in new buffer */ |
| hdr = buf_msg(*skb); |
| msg_set_hdr_sz(hdr, hlen); |
| msg_set_errcode(hdr, err); |
| msg_set_non_seq(hdr, 0); |
| msg_set_origport(hdr, msg_destport(_hdr)); |
| msg_set_destport(hdr, msg_origport(_hdr)); |
| msg_set_destnode(hdr, msg_prevnode(_hdr)); |
| msg_set_prevnode(hdr, own_node); |
| msg_set_orignode(hdr, own_node); |
| msg_set_size(hdr, hlen + dlen); |
| skb_orphan(_skb); |
| kfree_skb(_skb); |
| return true; |
| exit: |
| kfree_skb(_skb); |
| *skb = NULL; |
| return false; |
| } |
| |
| bool tipc_msg_skb_clone(struct sk_buff_head *msg, struct sk_buff_head *cpy) |
| { |
| struct sk_buff *skb, *_skb; |
| |
| skb_queue_walk(msg, skb) { |
| _skb = skb_clone(skb, GFP_ATOMIC); |
| if (!_skb) { |
| __skb_queue_purge(cpy); |
| pr_err_ratelimited("Failed to clone buffer chain\n"); |
| return false; |
| } |
| __skb_queue_tail(cpy, _skb); |
| } |
| return true; |
| } |
| |
| /** |
| * tipc_msg_lookup_dest(): try to find new destination for named message |
| * @skb: the buffer containing the message. |
| * @err: error code to be used by caller if lookup fails |
| * Does not consume buffer |
| * Returns true if a destination is found, false otherwise |
| */ |
| bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err) |
| { |
| struct tipc_msg *msg = buf_msg(skb); |
| u32 dport, dnode; |
| u32 onode = tipc_own_addr(net); |
| |
| if (!msg_isdata(msg)) |
| return false; |
| if (!msg_named(msg)) |
| return false; |
| if (msg_errcode(msg)) |
| return false; |
| *err = TIPC_ERR_NO_NAME; |
| if (skb_linearize(skb)) |
| return false; |
| msg = buf_msg(skb); |
| if (msg_reroute_cnt(msg)) |
| return false; |
| dnode = tipc_scope2node(net, msg_lookup_scope(msg)); |
| dport = tipc_nametbl_translate(net, msg_nametype(msg), |
| msg_nameinst(msg), &dnode); |
| if (!dport) |
| return false; |
| msg_incr_reroute_cnt(msg); |
| if (dnode != onode) |
| msg_set_prevnode(msg, onode); |
| msg_set_destnode(msg, dnode); |
| msg_set_destport(msg, dport); |
| *err = TIPC_OK; |
| |
| return true; |
| } |
| |
| /* tipc_msg_assemble() - assemble chain of fragments into one message |
| */ |
| bool tipc_msg_assemble(struct sk_buff_head *list) |
| { |
| struct sk_buff *skb, *tmp = NULL; |
| |
| if (skb_queue_len(list) == 1) |
| return true; |
| |
| while ((skb = __skb_dequeue(list))) { |
| skb->next = NULL; |
| if (tipc_buf_append(&tmp, &skb)) { |
| __skb_queue_tail(list, skb); |
| return true; |
| } |
| if (!tmp) |
| break; |
| } |
| __skb_queue_purge(list); |
| __skb_queue_head_init(list); |
| pr_warn("Failed do assemble buffer\n"); |
| return false; |
| } |
| |
| /* 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) |
| { |
| struct sk_buff *skb, *_skb; |
| struct sk_buff *frag = NULL; |
| struct sk_buff *head = NULL; |
| int hdr_len; |
| |
| /* Copy header if single buffer */ |
| if (skb_queue_len(list) == 1) { |
| skb = skb_peek(list); |
| hdr_len = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb)); |
| _skb = __pskb_copy(skb, hdr_len, GFP_ATOMIC); |
| if (!_skb) |
| return false; |
| __skb_queue_tail(rcvq, _skb); |
| return true; |
| } |
| |
| /* Clone all fragments and reassemble */ |
| skb_queue_walk(list, skb) { |
| frag = skb_clone(skb, GFP_ATOMIC); |
| if (!frag) |
| goto error; |
| frag->next = NULL; |
| if (tipc_buf_append(&head, &frag)) |
| break; |
| if (!head) |
| goto error; |
| } |
| __skb_queue_tail(rcvq, frag); |
| return true; |
| error: |
| pr_warn("Failed do clone local mcast rcv buffer\n"); |
| kfree_skb(head); |
| return false; |
| } |
| |
| bool tipc_msg_pskb_copy(u32 dst, struct sk_buff_head *msg, |
| struct sk_buff_head *cpy) |
| { |
| struct sk_buff *skb, *_skb; |
| |
| skb_queue_walk(msg, skb) { |
| _skb = pskb_copy(skb, GFP_ATOMIC); |
| if (!_skb) { |
| __skb_queue_purge(cpy); |
| return false; |
| } |
| msg_set_destnode(buf_msg(_skb), dst); |
| __skb_queue_tail(cpy, _skb); |
| } |
| return true; |
| } |
| |
| /* 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) |
| { |
| struct sk_buff *_skb, *tmp; |
| |
| if (skb_queue_empty(list) || less(seqno, buf_seqno(skb_peek(list)))) { |
| __skb_queue_head(list, skb); |
| return true; |
| } |
| |
| if (more(seqno, buf_seqno(skb_peek_tail(list)))) { |
| __skb_queue_tail(list, skb); |
| return true; |
| } |
| |
| skb_queue_walk_safe(list, _skb, tmp) { |
| if (more(seqno, buf_seqno(_skb))) |
| continue; |
| if (seqno == buf_seqno(_skb)) |
| break; |
| __skb_queue_before(list, _skb, skb); |
| return true; |
| } |
| kfree_skb(skb); |
| return false; |
| } |
| |
| void tipc_skb_reject(struct net *net, int err, struct sk_buff *skb, |
| struct sk_buff_head *xmitq) |
| { |
| if (tipc_msg_reverse(tipc_own_addr(net), &skb, err)) |
| __skb_queue_tail(xmitq, skb); |
| } |