--- /dev/null
+/*
+ * Copyright (c) 1982, 1986, 1988, 1990, 1993
+ * The Regents of the University of California. 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 name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+ *
+ * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
+ * ip_output.c,v 1.9 1994/11/16 10:17:10 jkh Exp
+ */
+
+/*
+ * Changes and additions relating to SLiRP are
+ * Copyright (c) 1995 Danny Gasparovski.
+ *
+ * Please read the file COPYRIGHT for the
+ * terms and conditions of the copyright.
+ */
+
+#include <slirp.h>
+
+/* Number of packets queued before we start sending
+ * (to prevent allocing too many mbufs) */
+#define IF_THRESH 10
+
+/*
+ * IP output. The packet in mbuf chain m contains a skeletal IP
+ * header (with len, off, ttl, proto, tos, src, dst).
+ * The mbuf chain containing the packet will be freed.
+ * The mbuf opt, if present, will not be freed.
+ */
+int
+ip_output(struct socket *so, struct mbuf *m0)
+{
+ Slirp *slirp = m0->slirp;
+ register struct ip *ip;
+ register struct mbuf *m = m0;
+ register int hlen = sizeof(struct ip );
+ int len, off, error = 0;
+
+ DEBUG_CALL("ip_output");
+ DEBUG_ARG("so = %lx", (long)so);
+ DEBUG_ARG("m0 = %lx", (long)m0);
+
+ ip = mtod(m, struct ip *);
+ /*
+ * Fill in IP header.
+ */
+ ip->ip_v = IPVERSION;
+ ip->ip_off &= IP_DF;
+ ip->ip_id = htons(slirp->ip_id++);
+ ip->ip_hl = hlen >> 2;
+
+ /*
+ * If small enough for interface, can just send directly.
+ */
+ if ((uint16_t)ip->ip_len <= IF_MTU) {
+ ip->ip_len = htons((uint16_t)ip->ip_len);
+ ip->ip_off = htons((uint16_t)ip->ip_off);
+ ip->ip_sum = 0;
+ ip->ip_sum = cksum(m, hlen);
+
+ if_output(so, m);
+ goto done;
+ }
+
+ /*
+ * Too large for interface; fragment if possible.
+ * Must be able to put at least 8 bytes per fragment.
+ */
+ if (ip->ip_off & IP_DF) {
+ error = -1;
+ goto bad;
+ }
+
+ len = (IF_MTU - hlen) &~ 7; /* ip databytes per packet */
+ if (len < 8) {
+ error = -1;
+ goto bad;
+ }
+
+ {
+ int mhlen, firstlen = len;
+ struct mbuf **mnext = &m->m_nextpkt;
+
+ /*
+ * Loop through length of segment after first fragment,
+ * make new header and copy data of each part and link onto chain.
+ */
+ m0 = m;
+ mhlen = sizeof (struct ip);
+ for (off = hlen + len; off < (uint16_t)ip->ip_len; off += len) {
+ register struct ip *mhip;
+ m = m_get(slirp);
+ if (m == NULL) {
+ error = -1;
+ goto sendorfree;
+ }
+ m->m_data += IF_MAXLINKHDR;
+ mhip = mtod(m, struct ip *);
+ *mhip = *ip;
+
+ m->m_len = mhlen;
+ mhip->ip_off = ((off - hlen) >> 3) + (ip->ip_off & ~IP_MF);
+ if (ip->ip_off & IP_MF)
+ mhip->ip_off |= IP_MF;
+ if (off + len >= (uint16_t)ip->ip_len)
+ len = (uint16_t)ip->ip_len - off;
+ else
+ mhip->ip_off |= IP_MF;
+ mhip->ip_len = htons((uint16_t)(len + mhlen));
+
+ if (m_copy(m, m0, off, len) < 0) {
+ error = -1;
+ goto sendorfree;
+ }
+
+ mhip->ip_off = htons((uint16_t)mhip->ip_off);
+ mhip->ip_sum = 0;
+ mhip->ip_sum = cksum(m, mhlen);
+ *mnext = m;
+ mnext = &m->m_nextpkt;
+ }
+ /*
+ * Update first fragment by trimming what's been copied out
+ * and updating header, then send each fragment (in order).
+ */
+ m = m0;
+ m_adj(m, hlen + firstlen - (uint16_t)ip->ip_len);
+ ip->ip_len = htons((uint16_t)m->m_len);
+ ip->ip_off = htons((uint16_t)(ip->ip_off | IP_MF));
+ ip->ip_sum = 0;
+ ip->ip_sum = cksum(m, hlen);
+sendorfree:
+ for (m = m0; m; m = m0) {
+ m0 = m->m_nextpkt;
+ m->m_nextpkt = NULL;
+ if (error == 0)
+ if_output(so, m);
+ else
+ m_free(m);
+ }
+ }
+
+done:
+ return (error);
+
+bad:
+ m_free(m0);
+ goto done;
+}
Code Review / kvmfornfv.git / blobdiff