Git Repo - qemu.git/blame_incremental

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Commit	Line	Data
	1	/*
	2	* Copyright (c) 1982, 1986, 1988, 1990, 1993
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. Neither the name of the University nor the names of its contributors
	14	* may be used to endorse or promote products derived from this software
	15	* without specific prior written permission.
	16	*
	17	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	18	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	19	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	20	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	21	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	22	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	23	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	24	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	25	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	26	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	27	* SUCH DAMAGE.
	28	*
	29	* @(#)ip_output.c 8.3 (Berkeley) 1/21/94
	30	* ip_output.c,v 1.9 1994/11/16 10:17:10 jkh Exp
	31	*/
	32
	33	/*
	34	* Changes and additions relating to SLiRP are
	35	* Copyright (c) 1995 Danny Gasparovski.
	36	*
	37	* Please read the file COPYRIGHT for the
	38	* terms and conditions of the copyright.
	39	*/
	40
	41	#include <slirp.h>
	42
	43	/* Number of packets queued before we start sending
	44	* (to prevent allocing too many mbufs) */
	45	#define IF_THRESH 10
	46
	47	/*
	48	* IP output. The packet in mbuf chain m contains a skeletal IP
	49	* header (with len, off, ttl, proto, tos, src, dst).
	50	* The mbuf chain containing the packet will be freed.
	51	* The mbuf opt, if present, will not be freed.
	52	*/
	53	int
	54	ip_output(struct socket so, struct mbuf m0)
	55	{
	56	Slirp *slirp = m0->slirp;
	57	register struct ip *ip;
	58	register struct mbuf *m = m0;
	59	register int hlen = sizeof(struct ip );
	60	int len, off, error = 0;
	61
	62	DEBUG_CALL("ip_output");
	63	DEBUG_ARG("so = %lx", (long)so);
	64	DEBUG_ARG("m0 = %lx", (long)m0);
	65
	66	ip = mtod(m, struct ip *);
	67	/*
	68	* Fill in IP header.
	69	*/
	70	ip->ip_v = IPVERSION;
	71	ip->ip_off &= IP_DF;
	72	ip->ip_id = htons(slirp->ip_id++);
	73	ip->ip_hl = hlen >> 2;
	74
	75	/*
	76	* If small enough for interface, can just send directly.
	77	*/
	78	if ((uint16_t)ip->ip_len <= IF_MTU) {
	79	ip->ip_len = htons((uint16_t)ip->ip_len);
	80	ip->ip_off = htons((uint16_t)ip->ip_off);
	81	ip->ip_sum = 0;
	82	ip->ip_sum = cksum(m, hlen);
	83
	84	if_output(so, m);
	85	goto done;
	86	}
	87
	88	/*
	89	* Too large for interface; fragment if possible.
	90	* Must be able to put at least 8 bytes per fragment.
	91	*/
	92	if (ip->ip_off & IP_DF) {
	93	error = -1;
	94	goto bad;
	95	}
	96
	97	len = (IF_MTU - hlen) &~ 7; /* ip databytes per packet */
	98	if (len < 8) {
	99	error = -1;
	100	goto bad;
	101	}
	102
	103	{
	104	int mhlen, firstlen = len;
	105	struct mbuf **mnext = &m->m_nextpkt;
	106
	107	/*
	108	* Loop through length of segment after first fragment,
	109	* make new header and copy data of each part and link onto chain.
	110	*/
	111	m0 = m;
	112	mhlen = sizeof (struct ip);
	113	for (off = hlen + len; off < (uint16_t)ip->ip_len; off += len) {
	114	register struct ip *mhip;
	115	m = m_get(slirp);
	116	if (m == NULL) {
	117	error = -1;
	118	goto sendorfree;
	119	}
	120	m->m_data += IF_MAXLINKHDR;
	121	mhip = mtod(m, struct ip *);
	122	mhip = ip;
	123
	124	m->m_len = mhlen;
	125	mhip->ip_off = ((off - hlen) >> 3) + (ip->ip_off & ~IP_MF);
	126	if (ip->ip_off & IP_MF)
	127	mhip->ip_off \|= IP_MF;
	128	if (off + len >= (uint16_t)ip->ip_len)
	129	len = (uint16_t)ip->ip_len - off;
	130	else
	131	mhip->ip_off \|= IP_MF;
	132	mhip->ip_len = htons((uint16_t)(len + mhlen));
	133
	134	if (m_copy(m, m0, off, len) < 0) {
	135	error = -1;
	136	goto sendorfree;
	137	}
	138
	139	mhip->ip_off = htons((uint16_t)mhip->ip_off);
	140	mhip->ip_sum = 0;
	141	mhip->ip_sum = cksum(m, mhlen);
	142	*mnext = m;
	143	mnext = &m->m_nextpkt;
	144	}
	145	/*
	146	* Update first fragment by trimming what's been copied out
	147	* and updating header, then send each fragment (in order).
	148	*/
	149	m = m0;
	150	m_adj(m, hlen + firstlen - (uint16_t)ip->ip_len);
	151	ip->ip_len = htons((uint16_t)m->m_len);
	152	ip->ip_off = htons((uint16_t)(ip->ip_off \| IP_MF));
	153	ip->ip_sum = 0;
	154	ip->ip_sum = cksum(m, hlen);
	155	sendorfree:
	156	for (m = m0; m; m = m0) {
	157	m0 = m->m_nextpkt;
	158	m->m_nextpkt = NULL;
	159	if (error == 0)
	160	if_output(so, m);
	161	else
	162	m_free(m);
	163	}
	164	}
	165
	166	done:
	167	return (error);
	168
	169	bad:
	170	m_free(m0);
	171	goto done;
	172	}