bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 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. |
aliguori | 2f5f899 | 2009-01-26 19:37:41 +0000 | [diff] [blame] | 13 | * 3. Neither the name of the University nor the names of its contributors |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 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 | |
blueswir1 | 7878ff6 | 2007-10-26 19:34:46 +0000 | [diff] [blame] | 43 | /* Number of packets queued before we start sending |
| 44 | * (to prevent allocing too many mbufs) */ |
| 45 | #define IF_THRESH 10 |
| 46 | |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 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 |
blueswir1 | 511d2b1 | 2009-03-07 15:32:56 +0000 | [diff] [blame] | 54 | ip_output(struct socket *so, struct mbuf *m0) |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 55 | { |
Jan Kiszka | 460fec6 | 2009-06-24 14:42:31 +0200 | [diff] [blame] | 56 | Slirp *slirp = m0->slirp; |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 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); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 65 | |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 66 | ip = mtod(m, struct ip *); |
| 67 | /* |
| 68 | * Fill in IP header. |
| 69 | */ |
| 70 | ip->ip_v = IPVERSION; |
| 71 | ip->ip_off &= IP_DF; |
Jan Kiszka | 460fec6 | 2009-06-24 14:42:31 +0200 | [diff] [blame] | 72 | ip->ip_id = htons(slirp->ip_id++); |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 73 | ip->ip_hl = hlen >> 2; |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 74 | |
| 75 | /* |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 76 | * If small enough for interface, can just send directly. |
| 77 | */ |
Stefan Weil | b6dce92 | 2010-07-22 22:15:23 +0200 | [diff] [blame] | 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); |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 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; |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 94 | goto bad; |
| 95 | } |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 96 | |
blueswir1 | 9634d90 | 2007-10-26 19:01:16 +0000 | [diff] [blame] | 97 | len = (IF_MTU - hlen) &~ 7; /* ip databytes per packet */ |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 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); |
Stefan Weil | b6dce92 | 2010-07-22 22:15:23 +0200 | [diff] [blame] | 113 | for (off = hlen + len; off < (uint16_t)ip->ip_len; off += len) { |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 114 | register struct ip *mhip; |
Jan Kiszka | 460fec6 | 2009-06-24 14:42:31 +0200 | [diff] [blame] | 115 | m = m_get(slirp); |
blueswir1 | 511d2b1 | 2009-03-07 15:32:56 +0000 | [diff] [blame] | 116 | if (m == NULL) { |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 117 | error = -1; |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 118 | goto sendorfree; |
| 119 | } |
blueswir1 | 9634d90 | 2007-10-26 19:01:16 +0000 | [diff] [blame] | 120 | m->m_data += IF_MAXLINKHDR; |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 121 | mhip = mtod(m, struct ip *); |
| 122 | *mhip = *ip; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 123 | |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 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; |
Stefan Weil | b6dce92 | 2010-07-22 22:15:23 +0200 | [diff] [blame] | 128 | if (off + len >= (uint16_t)ip->ip_len) |
| 129 | len = (uint16_t)ip->ip_len - off; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 130 | else |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 131 | mhip->ip_off |= IP_MF; |
Stefan Weil | b6dce92 | 2010-07-22 22:15:23 +0200 | [diff] [blame] | 132 | mhip->ip_len = htons((uint16_t)(len + mhlen)); |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 133 | |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 134 | if (m_copy(m, m0, off, len) < 0) { |
| 135 | error = -1; |
| 136 | goto sendorfree; |
| 137 | } |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 138 | |
Stefan Weil | b6dce92 | 2010-07-22 22:15:23 +0200 | [diff] [blame] | 139 | mhip->ip_off = htons((uint16_t)mhip->ip_off); |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 140 | mhip->ip_sum = 0; |
| 141 | mhip->ip_sum = cksum(m, mhlen); |
| 142 | *mnext = m; |
| 143 | mnext = &m->m_nextpkt; |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 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; |
Stefan Weil | b6dce92 | 2010-07-22 22:15:23 +0200 | [diff] [blame] | 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)); |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 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; |
blueswir1 | 511d2b1 | 2009-03-07 15:32:56 +0000 | [diff] [blame] | 158 | m->m_nextpkt = NULL; |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 159 | if (error == 0) |
| 160 | if_output(so, m); |
| 161 | else |
Jan Kiszka | 3acccfc | 2011-07-20 12:20:16 +0200 | [diff] [blame] | 162 | m_free(m); |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 163 | } |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 164 | } |
| 165 | |
| 166 | done: |
| 167 | return (error); |
| 168 | |
| 169 | bad: |
Jan Kiszka | 3acccfc | 2011-07-20 12:20:16 +0200 | [diff] [blame] | 170 | m_free(m0); |
bellard | f0cbd3e | 2004-04-22 00:10:48 +0000 | [diff] [blame] | 171 | goto done; |
| 172 | } |