out_free:
pr_warn_ratelimited("Unable to build fragment list\n");
kfree_skb(*buf);
+ kfree_skb(*headbuf);
+ *buf = *headbuf = NULL;
return 0;
}
+
+
+/**
+ * tipc_msg_build2 - create buffer chain containing specified header and data
+ * @mhdr: Message header, to be prepended to data
+ * @iov: User data
+ * @offset: Posision in iov to start copying from
+ * @dsz: Total length of user data
+ * @pktmax: Max packet size that can be used
+ * @chain: Buffer or chain of buffers to be returned to caller
+ * Returns message data size or errno: -ENOMEM, -EFAULT
+ */
+int tipc_msg_build2(struct tipc_msg *mhdr, struct iovec const *iov,
+ int offset, int dsz, int pktmax , struct sk_buff **chain)
+{
+ int mhsz = msg_hdr_sz(mhdr);
+ int msz = mhsz + dsz;
+ int pktno = 1;
+ int pktsz;
+ int pktrem = pktmax;
+ int drem = dsz;
+ struct tipc_msg pkthdr;
+ struct sk_buff *buf, *prev;
+ char *pktpos;
+ int rc;
+
+ msg_set_size(mhdr, msz);
+
+ /* No fragmentation needed? */
+ if (likely(msz <= pktmax)) {
+ buf = tipc_buf_acquire(msz);
+ *chain = buf;
+ if (unlikely(!buf))
+ return -ENOMEM;
+ skb_copy_to_linear_data(buf, mhdr, mhsz);
+ pktpos = buf->data + mhsz;
+ if (!dsz || !memcpy_fromiovecend(pktpos, iov, offset, dsz))
+ return dsz;
+ rc = -EFAULT;
+ goto error;
+ }
+
+ /* Prepare reusable fragment header */
+ tipc_msg_init(&pkthdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
+ INT_H_SIZE, msg_destnode(mhdr));
+ msg_set_size(&pkthdr, pktmax);
+ msg_set_fragm_no(&pkthdr, pktno);
+
+ /* Prepare first fragment */
+ *chain = buf = tipc_buf_acquire(pktmax);
+ if (!buf)
+ return -ENOMEM;
+ pktpos = buf->data;
+ skb_copy_to_linear_data(buf, &pkthdr, INT_H_SIZE);
+ pktpos += INT_H_SIZE;
+ pktrem -= INT_H_SIZE;
+ skb_copy_to_linear_data_offset(buf, INT_H_SIZE, mhdr, mhsz);
+ pktpos += mhsz;
+ pktrem -= mhsz;
+
+ do {
+ if (drem < pktrem)
+ pktrem = drem;
+
+ if (memcpy_fromiovecend(pktpos, iov, offset, pktrem)) {
+ rc = -EFAULT;
+ goto error;
+ }
+ drem -= pktrem;
+ offset += pktrem;
+
+ if (!drem)
+ break;
+
+ /* Prepare new fragment: */
+ if (drem < (pktmax - INT_H_SIZE))
+ pktsz = drem + INT_H_SIZE;
+ else
+ pktsz = pktmax;
+ prev = buf;
+ buf = tipc_buf_acquire(pktsz);
+ if (!buf) {
+ rc = -ENOMEM;
+ goto error;
+ }
+ prev->next = buf;
+ msg_set_type(&pkthdr, FRAGMENT);
+ msg_set_size(&pkthdr, pktsz);
+ msg_set_fragm_no(&pkthdr, ++pktno);
+ skb_copy_to_linear_data(buf, &pkthdr, INT_H_SIZE);
+ pktpos = buf->data + INT_H_SIZE;
+ pktrem = pktsz - INT_H_SIZE;
+
+ } while (1);
+
+ msg_set_type(buf_msg(buf), LAST_FRAGMENT);
+ return dsz;
+error:
+ kfree_skb_list(*chain);
+ *chain = NULL;
+ return rc;
+}
+
+/**
+ * tipc_msg_bundle(): Append contents of a buffer to tail of an existing one
+ * @bbuf: the existing buffer ("bundle")
+ * @buf: buffer to be appended
+ * @mtu: max allowable size for the bundle buffer
+ * Consumes buffer if successful
+ * Returns true if bundling could be performed, otherwise false
+ */
+bool tipc_msg_bundle(struct sk_buff *bbuf, struct sk_buff *buf, u32 mtu)
+{
+ struct tipc_msg *bmsg = buf_msg(bbuf);
+ struct tipc_msg *msg = buf_msg(buf);
+ unsigned int bsz = msg_size(bmsg);
+ unsigned int msz = msg_size(msg);
+ u32 start = align(bsz);
+ u32 max = mtu - INT_H_SIZE;
+ u32 pad = start - bsz;
+
+ if (likely(msg_user(msg) == MSG_FRAGMENTER))
+ return false;
+ if (unlikely(msg_user(msg) == CHANGEOVER_PROTOCOL))
+ return false;
+ if (unlikely(msg_user(msg) == BCAST_PROTOCOL))
+ return false;
+ if (likely(msg_user(bmsg) != MSG_BUNDLER))
+ return false;
+ if (likely(msg_type(bmsg) != BUNDLE_OPEN))
+ return false;
+ if (unlikely(skb_tailroom(bbuf) < (pad + msz)))
+ return false;
+ if (unlikely(max < (start + msz)))
+ return false;
+
+ skb_put(bbuf, pad + msz);
+ skb_copy_to_linear_data_offset(bbuf, start, buf->data, msz);
+ msg_set_size(bmsg, start + msz);
+ msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1);
+ bbuf->next = buf->next;
+ kfree_skb(buf);
+ return true;
+}
+
+/**
+ * tipc_msg_make_bundle(): Create bundle buf and append message to its tail
+ * @buf: buffer to be appended and replaced
+ * @mtu: max allowable size for the bundle buffer, inclusive header
+ * @dnode: destination node for message. (Not always present in header)
+ * Replaces buffer if successful
+ * Returns true if sucess, otherwise false
+ */
+bool tipc_msg_make_bundle(struct sk_buff **buf, u32 mtu, u32 dnode)
+{
+ struct sk_buff *bbuf;
+ struct tipc_msg *bmsg;
+ struct tipc_msg *msg = buf_msg(*buf);
+ u32 msz = msg_size(msg);
+ u32 max = mtu - INT_H_SIZE;
+
+ if (msg_user(msg) == MSG_FRAGMENTER)
+ return false;
+ if (msg_user(msg) == CHANGEOVER_PROTOCOL)
+ return false;
+ if (msg_user(msg) == BCAST_PROTOCOL)
+ return false;
+ if (msz > (max / 2))
+ return false;
+
+ bbuf = tipc_buf_acquire(max);
+ if (!bbuf)
+ return false;
+
+ skb_trim(bbuf, INT_H_SIZE);
+ bmsg = buf_msg(bbuf);
+ tipc_msg_init(bmsg, MSG_BUNDLER, BUNDLE_OPEN, INT_H_SIZE, dnode);
+ msg_set_seqno(bmsg, msg_seqno(msg));
+ msg_set_ack(bmsg, msg_ack(msg));
+ msg_set_bcast_ack(bmsg, msg_bcast_ack(msg));
+ bbuf->next = (*buf)->next;
+ tipc_msg_bundle(bbuf, *buf, mtu);
+ *buf = bbuf;
+ return true;
+}
+
+/**
+ * tipc_msg_reverse(): swap source and destination addresses and add error code
+ * @buf: buffer containing message to be reversed
+ * @dnode: return value: node where to send message after reversal
+ * @err: error code to be set in message
+ * Consumes buffer if failure
+ * Returns true if success, otherwise false
+ */
+bool tipc_msg_reverse(struct sk_buff *buf, u32 *dnode, int err)
+{
+ struct tipc_msg *msg = buf_msg(buf);
+ uint imp = msg_importance(msg);
+ struct tipc_msg ohdr;
+ uint rdsz = min_t(uint, msg_data_sz(msg), MAX_FORWARD_SIZE);
+
+ if (skb_linearize(buf))
+ goto exit;
+ if (msg_dest_droppable(msg))
+ goto exit;
+ if (msg_errcode(msg))
+ goto exit;
+
+ memcpy(&ohdr, msg, msg_hdr_sz(msg));
+ imp = min_t(uint, imp + 1, TIPC_CRITICAL_IMPORTANCE);
+ if (msg_isdata(msg))
+ msg_set_importance(msg, imp);
+ msg_set_errcode(msg, err);
+ msg_set_origport(msg, msg_destport(&ohdr));
+ msg_set_destport(msg, msg_origport(&ohdr));
+ msg_set_prevnode(msg, tipc_own_addr);
+ if (!msg_short(msg)) {
+ msg_set_orignode(msg, msg_destnode(&ohdr));
+ msg_set_destnode(msg, msg_orignode(&ohdr));
+ }
+ msg_set_size(msg, msg_hdr_sz(msg) + rdsz);
+ skb_trim(buf, msg_size(msg));
+ skb_orphan(buf);
+ *dnode = msg_orignode(&ohdr);
+ return true;
+exit:
+ kfree_skb(buf);
+ return false;
+}
+
+/**
+ * tipc_msg_eval: determine fate of message that found no destination
+ * @buf: the buffer containing the message.
+ * @dnode: return value: next-hop node, if message to be forwarded
+ * @err: error code to use, if message to be rejected
+ *
+ * Does not consume buffer
+ * Returns 0 (TIPC_OK) if message ok and we can try again, -TIPC error
+ * code if message to be rejected
+ */
+int tipc_msg_eval(struct sk_buff *buf, u32 *dnode)
+{
+ struct tipc_msg *msg = buf_msg(buf);
+ u32 dport;
+
+ if (msg_type(msg) != TIPC_NAMED_MSG)
+ return -TIPC_ERR_NO_PORT;
+ if (skb_linearize(buf))
+ return -TIPC_ERR_NO_NAME;
+ if (msg_data_sz(msg) > MAX_FORWARD_SIZE)
+ return -TIPC_ERR_NO_NAME;
+ if (msg_reroute_cnt(msg) > 0)
+ return -TIPC_ERR_NO_NAME;
+
+ *dnode = addr_domain(msg_lookup_scope(msg));
+ dport = tipc_nametbl_translate(msg_nametype(msg),
+ msg_nameinst(msg),
+ dnode);
+ if (!dport)
+ return -TIPC_ERR_NO_NAME;
+ msg_incr_reroute_cnt(msg);
+ msg_set_destnode(msg, *dnode);
+ msg_set_destport(msg, dport);
+ return TIPC_OK;
+}
projects / openwrt / staging / blogic.git / commitdiff