Imported Upstream version 1.2.0upstream/1.2.0

1 files changed, 172 insertions, 0 deletions

diff --git a/slirp/ip_output.c b/slirp/ip_output.c
new file mode 100644
index 000000000..c82830fe7
--- /dev/null
+++ b/slirp/ip_output.c
@@ -0,0 +1,172 @@
+/*
+ * 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;
+}