2  * net/tipc/msg.c: TIPC message header routines
4  * Copyright (c) 2000-2006, 2014-2015, Ericsson AB
5  * Copyright (c) 2005, 2010-2011, Wind River Systems
39 #include "msg.h"
54 const int one_page_mtu = PAGE_SIZE - SKB_DATA_ALIGN(BUF_OVERHEAD) -
58  * tipc_buf_acquire - creates a TIPC message buffer
59  * @size: message size (including TIPC header)
62  * Return: a new buffer with data pointers set to the specified size.
68 struct sk_buff *tipc_buf_acquire(u32 size, gfp_t gfp)  in tipc_buf_acquire()  argument
72 	skb = alloc_skb_fclone(BUF_OVERHEAD + size, gfp);  in tipc_buf_acquire()
75 		skb_put(skb, size);  in tipc_buf_acquire()
76 		skb->next = NULL;  in tipc_buf_acquire()
101 	struct tipc_msg *msg;  in tipc_msg_create()  local
108 	msg = buf_msg(buf);  in tipc_msg_create()
109 	tipc_msg_init(onode, msg, user, type, hdr_sz, dnode);  in tipc_msg_create()
110 	msg_set_size(msg, hdr_sz + data_sz);  in tipc_msg_create()
111 	msg_set_origport(msg, oport);  in tipc_msg_create()
112 	msg_set_destport(msg, dport);  in tipc_msg_create()
113 	msg_set_errcode(msg, errcode);  in tipc_msg_create()
119  *            out: set when successful non-complete reassembly, otherwise NULL
129 	struct tipc_msg *msg;  in tipc_buf_append()  local
137 	msg = buf_msg(frag);  in tipc_buf_append()
138 	fragid = msg_type(msg);  in tipc_buf_append()
139 	frag->next = NULL;  in tipc_buf_append()
140 	skb_pull(frag, msg_hdr_sz(msg));  in tipc_buf_append()
152 		TIPC_SKB_CB(head)->tail = NULL;  in tipc_buf_append()
167 		tail = TIPC_SKB_CB(head)->tail;  in tipc_buf_append()
169 			skb_shinfo(head)->frag_list = frag;  in tipc_buf_append()
171 			tail->next = frag;  in tipc_buf_append()
172 		head->truesize += frag->truesize;  in tipc_buf_append()
173 		head->data_len += frag->len;  in tipc_buf_append()
174 		head->len += frag->len;  in tipc_buf_append()
175 		TIPC_SKB_CB(head)->tail = frag;  in tipc_buf_append()
179 		TIPC_SKB_CB(head)->validated = 0;  in tipc_buf_append()
183 		TIPC_SKB_CB(head)->tail = NULL;  in tipc_buf_append()
199  * @mss: max allowable size of buffer
200  * @dlen: size of data to be appended
218 		if (!skb || skb->len >= mss) {  in tipc_msg_append()
221 				return -ENOMEM;  in tipc_msg_append()
234 		cpy = min_t(size_t, rem, mss - mlen);  in tipc_msg_append()
235 		if (cpy != copy_from_iter(skb->data + mlen, cpy, &m->msg_iter))  in tipc_msg_append()
236 			return -EFAULT;  in tipc_msg_append()
239 		rem -= cpy;  in tipc_msg_append()
240 		total += msg_blocks(hdr) - curr;  in tipc_msg_append()
242 	return total - accounted;  in tipc_msg_append()
245 /* tipc_msg_validate - validate basic format of received message
263 	if (unlikely(skb->truesize / buf_roundup_len(skb) >= 4)) {  in tipc_msg_validate()
271 	if (unlikely(TIPC_SKB_CB(skb)->validated))  in tipc_msg_validate()
290 	if (unlikely((msz - hsz) > TIPC_MAX_USER_MSG_SIZE))  in tipc_msg_validate()
292 	if (unlikely(skb->len < msz))  in tipc_msg_validate()
295 	TIPC_SKB_CB(skb)->validated = 1;  in tipc_msg_validate()
300  * tipc_msg_fragment - build a fragment skb list for TIPC message
303  * @hdr: internal msg header to be put on the top of the fragments
304  * @pktmax: max size of a fragment incl. the header
307  * Return: 0 if the fragmentation is successful, otherwise: -EINVAL
308  * or -ENOMEM
318 	/* Non-linear buffer? */  in tipc_msg_fragment()
320 		return -ENOMEM;  in tipc_msg_fragment()
322 	data = (u8 *)skb->data;  in tipc_msg_fragment()
324 	dmax = pktmax - INT_H_SIZE;  in tipc_msg_fragment()
326 		return -EINVAL;  in tipc_msg_fragment()
355 	return -ENOMEM;  in tipc_msg_fragment()
359  * tipc_msg_build - create buffer chain containing specified header and data
364  * @pktmax: Max packet size that can be used
370  * Return: message data size or errno: -ENOMEM, -EFAULT
395 				return -ENOMEM;  in tipc_msg_build()
402 			return -ENOMEM;  in tipc_msg_build()
407 		pktpos = skb->data + mhsz;  in tipc_msg_build()
408 		if (copy_from_iter_full(pktpos, dsz, &m->msg_iter))  in tipc_msg_build()
410 		rc = -EFAULT;  in tipc_msg_build()
424 		return -ENOMEM;  in tipc_msg_build()
427 	pktpos = skb->data;  in tipc_msg_build()
430 	pktrem -= INT_H_SIZE;  in tipc_msg_build()
433 	pktrem -= mhsz;  in tipc_msg_build()
439 		if (!copy_from_iter_full(pktpos, pktrem, &m->msg_iter)) {  in tipc_msg_build()
440 			rc = -EFAULT;  in tipc_msg_build()
443 		drem -= pktrem;  in tipc_msg_build()
449 		if (drem < (pktmax - INT_H_SIZE))  in tipc_msg_build()
455 			rc = -ENOMEM;  in tipc_msg_build()
464 		pktpos = skb->data + INT_H_SIZE;  in tipc_msg_build()
465 		pktrem = pktsz - INT_H_SIZE;  in tipc_msg_build()
477  * tipc_msg_bundle - Append contents of a buffer to tail of an existing one
479  * @msg: message to be appended
480  * @max: max allowable size for the bundle buffer
484 static bool tipc_msg_bundle(struct sk_buff *bskb, struct tipc_msg *msg,  in tipc_msg_bundle()  argument
485 			    u32 max)  in tipc_msg_bundle()  argument
490 	msz = msg_size(msg);  in tipc_msg_bundle()
493 	pad = offset - bsz;  in tipc_msg_bundle()
497 	if (unlikely(max < (offset + msz)))  in tipc_msg_bundle()
501 	skb_copy_to_linear_data_offset(bskb, offset, msg, msz);  in tipc_msg_bundle()
508  * tipc_msg_try_bundle - Try to bundle a new message to the last one
511  * @mss: max message size (header inclusive)
523 	struct tipc_msg *msg, *inner, *outer;  in tipc_msg_try_bundle()  local
527 	msg = buf_msg(*skb);  in tipc_msg_try_bundle()
528 	if (msg_user(msg) == MSG_FRAGMENTER)  in tipc_msg_try_bundle()
530 	if (msg_user(msg) == TUNNEL_PROTOCOL)  in tipc_msg_try_bundle()
532 	if (msg_user(msg) == BCAST_PROTOCOL)  in tipc_msg_try_bundle()
534 	if (mss <= INT_H_SIZE + msg_size(msg))  in tipc_msg_try_bundle()
549 	if (unlikely(mss < BUF_ALIGN(INT_H_SIZE + tsz) + msg_size(msg)))  in tipc_msg_try_bundle()
551 	if (unlikely(pskb_expand_head(tskb, INT_H_SIZE, mss - tsz - INT_H_SIZE,  in tipc_msg_try_bundle()
565 	if (likely(tipc_msg_bundle(tskb, msg, mss))) {  in tipc_msg_try_bundle()
576  *  @pos: position in outer message of msg to be extracted.
577  *  Returns position of next msg.
591 	if (unlikely(*pos > (msg_data_sz(hdr) - MIN_H_SIZE)))  in tipc_msg_extract()
646 	/* Don't return data along with SYN+, - sender has a clone */  in tipc_msg_reverse()
654 	memcpy((*skb)->data, _skb->data, msg_hdr_sz(_hdr));  in tipc_msg_reverse()
655 	memcpy((*skb)->data + hlen, msg_data(_hdr), dlen);  in tipc_msg_reverse()
677 bool tipc_msg_skb_clone(struct sk_buff_head *msg, struct sk_buff_head *cpy)  in tipc_msg_skb_clone()  argument
681 	skb_queue_walk(msg, skb) {  in tipc_msg_skb_clone()
703 	struct tipc_msg *msg = buf_msg(skb);  in tipc_msg_lookup_dest()  local
704 	u32 scope = msg_lookup_scope(msg);  in tipc_msg_lookup_dest()
706 	u32 inst = msg_nameinst(msg);  in tipc_msg_lookup_dest()
710 	if (!msg_isdata(msg))  in tipc_msg_lookup_dest()
712 	if (!msg_named(msg))  in tipc_msg_lookup_dest()
714 	if (msg_errcode(msg))  in tipc_msg_lookup_dest()
719 	msg = buf_msg(skb);  in tipc_msg_lookup_dest()
720 	if (msg_reroute_cnt(msg))  in tipc_msg_lookup_dest()
723 		   msg_nametype(msg), inst, inst);  in tipc_msg_lookup_dest()
727 	msg_incr_reroute_cnt(msg);  in tipc_msg_lookup_dest()
729 		msg_set_prevnode(msg, self);  in tipc_msg_lookup_dest()
730 	msg_set_destnode(msg, sk.node);  in tipc_msg_lookup_dest()
731 	msg_set_destport(msg, sk.ref);  in tipc_msg_lookup_dest()
737 /* tipc_msg_assemble() - assemble chain of fragments into one message
747 		skb->next = NULL;  in tipc_msg_assemble()
761 /* tipc_msg_reassemble() - clone a buffer chain of fragments and
787 		frag->next = NULL;  in tipc_msg_reassemble()
801 bool tipc_msg_pskb_copy(u32 dst, struct sk_buff_head *msg,  in tipc_msg_pskb_copy()  argument
806 	skb_queue_walk(msg, skb) {  in tipc_msg_pskb_copy()