initial user mode network support

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@733 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 376 insertions, 0 deletions

diff --git a/slirp/ip_icmp.c b/slirp/ip_icmp.c
new file mode 100644
index 0000000000..8bc97a0786
--- /dev/null
+++ b/slirp/ip_icmp.c
@@ -0,0 +1,376 @@
+/*
+ * Copyright (c) 1982, 1986, 1988, 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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_icmp.c	8.2 (Berkeley) 1/4/94
+ * ip_icmp.c,v 1.7 1995/05/30 08:09:42 rgrimes Exp
+ */
+
+#include "slirp.h"
+#include "ip_icmp.h"
+
+struct icmpstat icmpstat;
+
+/* The message sent when emulating PING */
+/* Be nice and tell them it's just a psuedo-ping packet */
+char icmp_ping_msg[] = "This is a psuedo-PING packet used by Slirp to emulate ICMP ECHO-REQUEST packets.\n";
+
+/* list of actions for icmp_error() on RX of an icmp message */
+static int icmp_flush[19] = {
+/*  ECHO REPLY (0)  */   0,
+		         1,
+		         1,
+/* DEST UNREACH (3) */   1,
+/* SOURCE QUENCH (4)*/   1,
+/* REDIRECT (5) */       1,
+		         1,
+		         1,
+/* ECHO (8) */           0,
+/* ROUTERADVERT (9) */   1,
+/* ROUTERSOLICIT (10) */ 1,
+/* TIME EXCEEDED (11) */ 1,
+/* PARAMETER PROBLEM (12) */ 1,
+/* TIMESTAMP (13) */     0,
+/* TIMESTAMP REPLY (14) */ 0,
+/* INFO (15) */          0,
+/* INFO REPLY (16) */    0,
+/* ADDR MASK (17) */     0,
+/* ADDR MASK REPLY (18) */ 0 
+};
+
+/*
+ * Process a received ICMP message.
+ */
+void
+icmp_input(m, hlen)
+     struct mbuf *m;
+     int hlen;
+{
+  register struct icmp *icp;
+  register struct ip *ip=mtod(m, struct ip *);
+  int icmplen=ip->ip_len;
+  /* int code; */
+	
+  DEBUG_CALL("icmp_input");
+  DEBUG_ARG("m = %lx", (long )m);
+  DEBUG_ARG("m_len = %d", m->m_len);
+
+  icmpstat.icps_received++;
+	
+  /*
+   * Locate icmp structure in mbuf, and check
+   * that its not corrupted and of at least minimum length.
+   */
+  if (icmplen < ICMP_MINLEN) {          /* min 8 bytes payload */
+    icmpstat.icps_tooshort++;
+  freeit:
+    m_freem(m);
+    goto end_error;
+  }
+
+  m->m_len -= hlen;
+  m->m_data += hlen;
+  icp = mtod(m, struct icmp *);
+  if (cksum(m, icmplen)) {
+    icmpstat.icps_checksum++;
+    goto freeit;
+  }
+  m->m_len += hlen;
+  m->m_data -= hlen;
+  
+  /*	icmpstat.icps_inhist[icp->icmp_type]++; */
+  /* code = icp->icmp_code; */
+
+  DEBUG_ARG("icmp_type = %d", icp->icmp_type);
+  switch (icp->icmp_type) {
+  case ICMP_ECHO:
+    icp->icmp_type = ICMP_ECHOREPLY;
+    ip->ip_len += hlen;	             /* since ip_input subtracts this */
+    if (ip->ip_dst.s_addr == our_addr.s_addr || 
+	(ip->ip_dst.s_addr == (special_addr.s_addr|htonl(CTL_ALIAS))) ) {
+      icmp_reflect(m);
+    } else {
+      struct socket *so;
+      struct sockaddr_in addr;
+      if ((so = socreate()) == NULL) goto freeit;
+      if(udp_attach(so) == -1) {
+	DEBUG_MISC((dfd,"icmp_input udp_attach errno = %d-%s\n", 
+		    errno,strerror(errno)));
+	sofree(so);
+	m_free(m);
+	goto end_error;
+      }
+      so->so_m = m;
+      so->so_faddr = ip->ip_dst;
+      so->so_fport = htons(7);
+      so->so_laddr = ip->ip_src;
+      so->so_lport = htons(9);
+      so->so_iptos = ip->ip_tos;
+      so->so_type = IPPROTO_ICMP;
+      so->so_state = SS_ISFCONNECTED;
+      
+      /* Send the packet */
+      addr.sin_family = AF_INET;
+      if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr) {
+	/* It's an alias */
+	switch(ntohl(so->so_faddr.s_addr) & 0xff) {
+	case CTL_DNS:
+	  addr.sin_addr = dns_addr;
+	  break;
+	case CTL_ALIAS:
+	default:
+	  addr.sin_addr = loopback_addr;
+	  break;
+	}
+      } else {
+	addr.sin_addr = so->so_faddr;
+      }
+      addr.sin_port = so->so_fport;
+      if(sendto(so->s, icmp_ping_msg, strlen(icmp_ping_msg), 0,
+		(struct sockaddr *)&addr, sizeof(addr)) == -1) {
+	DEBUG_MISC((dfd,"icmp_input udp sendto tx errno = %d-%s\n",
+		    errno,strerror(errno)));
+	icmp_error(m, ICMP_UNREACH,ICMP_UNREACH_NET, 0,strerror(errno)); 
+	udp_detach(so);
+      }
+    } /* if ip->ip_dst.s_addr == our_addr.s_addr */
+    break;
+  case ICMP_UNREACH:
+    /* XXX? report error? close socket? */
+  case ICMP_TIMXCEED:
+  case ICMP_PARAMPROB:
+  case ICMP_SOURCEQUENCH:
+  case ICMP_TSTAMP:
+  case ICMP_MASKREQ:
+  case ICMP_REDIRECT:
+    icmpstat.icps_notsupp++;
+    m_freem(m);
+    break;
+    
+  default:
+    icmpstat.icps_badtype++;
+    m_freem(m);
+  } /* swith */
+
+end_error:
+  /* m is m_free()'d xor put in a socket xor or given to ip_send */
+  return;
+}
+
+
+/*
+ *	Send an ICMP message in response to a situation
+ *
+ *	RFC 1122: 3.2.2	MUST send at least the IP header and 8 bytes of header. MAY send more (we do).
+ *			MUST NOT change this header information.
+ *			MUST NOT reply to a multicast/broadcast IP address.
+ *			MUST NOT reply to a multicast/broadcast MAC address.
+ *			MUST reply to only the first fragment.
+ */
+/*
+ * Send ICMP_UNREACH back to the source regarding msrc.
+ * mbuf *msrc is used as a template, but is NOT m_free()'d.
+ * It is reported as the bad ip packet.  The header should
+ * be fully correct and in host byte order.
+ * ICMP fragmentation is illegal.  All machines must accept 576 bytes in one 
+ * packet.  The maximum payload is 576-20(ip hdr)-8(icmp hdr)=548
+ */
+
+#define ICMP_MAXDATALEN (IP_MSS-28)
+void
+icmp_error(msrc, type, code, minsize, message)
+     struct mbuf *msrc;
+     u_char type;
+     u_char code;
+     int minsize;
+     char *message;
+{
+  unsigned hlen, shlen, s_ip_len;
+  register struct ip *ip;
+  register struct icmp *icp;
+  register struct mbuf *m;
+
+  DEBUG_CALL("icmp_error");
+  DEBUG_ARG("msrc = %lx", (long )msrc);
+  DEBUG_ARG("msrc_len = %d", msrc->m_len);
+
+  if(type!=ICMP_UNREACH && type!=ICMP_TIMXCEED) goto end_error;
+
+  /* check msrc */
+  if(!msrc) goto end_error;
+  ip = mtod(msrc, struct ip *);
+#if DEBUG  
+  { char bufa[20], bufb[20];
+    strcpy(bufa, inet_ntoa(ip->ip_src));
+    strcpy(bufb, inet_ntoa(ip->ip_dst));
+    DEBUG_MISC((dfd, " %.16s to %.16s\n", bufa, bufb));
+  }
+#endif
+  if(ip->ip_off & IP_OFFMASK) goto end_error;    /* Only reply to fragment 0 */
+
+  shlen=ip->ip_hl << 2;
+  s_ip_len=ip->ip_len;
+  if(ip->ip_p == IPPROTO_ICMP) {
+    icp = (struct icmp *)((char *)ip + shlen);
+    /*
+     *	Assume any unknown ICMP type is an error. This isn't
+     *	specified by the RFC, but think about it..
+     */
+    if(icp->icmp_type>18 || icmp_flush[icp->icmp_type]) goto end_error;
+  }
+
+  /* make a copy */
+  if(!(m=m_get())) goto end_error;               /* get mbuf */
+  { int new_m_size;
+    new_m_size=sizeof(struct ip )+ICMP_MINLEN+msrc->m_len+ICMP_MAXDATALEN;
+    if(new_m_size>m->m_size) m_inc(m, new_m_size);
+  }
+  memcpy(m->m_data, msrc->m_data, msrc->m_len);
+  m->m_len = msrc->m_len;                        /* copy msrc to m */
+
+  /* make the header of the reply packet */
+  ip  = mtod(m, struct ip *);
+  hlen= sizeof(struct ip );     /* no options in reply */
+  
+  /* fill in icmp */
+  m->m_data += hlen;                  
+  m->m_len -= hlen;
+
+  icp = mtod(m, struct icmp *);
+
+  if(minsize) s_ip_len=shlen+ICMP_MINLEN;   /* return header+8b only */
+  else if(s_ip_len>ICMP_MAXDATALEN)         /* maximum size */
+    s_ip_len=ICMP_MAXDATALEN;
+
+  m->m_len=ICMP_MINLEN+s_ip_len;        /* 8 bytes ICMP header */  
+
+  /* min. size = 8+sizeof(struct ip)+8 */
+
+  icp->icmp_type = type;
+  icp->icmp_code = code;
+  icp->icmp_id = 0;
+  icp->icmp_seq = 0;
+
+  memcpy(&icp->icmp_ip, msrc->m_data, s_ip_len);   /* report the ip packet */
+  HTONS(icp->icmp_ip.ip_len);
+  HTONS(icp->icmp_ip.ip_id);
+  HTONS(icp->icmp_ip.ip_off);
+
+#if DEBUG
+  if(message) {           /* DEBUG : append message to ICMP packet */
+    int message_len;
+    char *cpnt;
+    message_len=strlen(message);
+    if(message_len>ICMP_MAXDATALEN) message_len=ICMP_MAXDATALEN;
+    cpnt=(char *)m->m_data+m->m_len;
+    memcpy(cpnt, message, message_len);
+    m->m_len+=message_len;
+  }
+#endif
+
+  icp->icmp_cksum = 0;
+  icp->icmp_cksum = cksum(m, m->m_len);
+
+  m->m_data -= hlen;
+  m->m_len += hlen;
+
+  /* fill in ip */
+  ip->ip_hl = hlen >> 2;
+  ip->ip_len = m->m_len;
+  
+  ip->ip_tos=((ip->ip_tos & 0x1E) | 0xC0);  /* high priority for errors */
+
+  ip->ip_ttl = MAXTTL;
+  ip->ip_p = IPPROTO_ICMP;
+  ip->ip_dst = ip->ip_src;    /* ip adresses */
+  ip->ip_src = our_addr;
+
+  (void ) ip_output((struct socket *)NULL, m);
+  
+  icmpstat.icps_reflect++;
+
+end_error:
+  return;
+}
+#undef ICMP_MAXDATALEN
+
+/*
+ * Reflect the ip packet back to the source
+ */
+void
+icmp_reflect(m)
+     struct mbuf *m;
+{
+  register struct ip *ip = mtod(m, struct ip *);
+  int hlen = ip->ip_hl << 2;
+  int optlen = hlen - sizeof(struct ip );
+  register struct icmp *icp;
+
+  /*
+   * Send an icmp packet back to the ip level,
+   * after supplying a checksum.
+   */
+  m->m_data += hlen;
+  m->m_len -= hlen;
+  icp = mtod(m, struct icmp *);
+
+  icp->icmp_cksum = 0;
+  icp->icmp_cksum = cksum(m, ip->ip_len - hlen);
+
+  m->m_data -= hlen;
+  m->m_len += hlen;
+
+  /* fill in ip */
+  if (optlen > 0) {
+    /*
+     * Strip out original options by copying rest of first
+     * mbuf's data back, and adjust the IP length.
+     */
+    memmove((caddr_t)(ip + 1), (caddr_t)ip + hlen,
+	    (unsigned )(m->m_len - hlen));
+    hlen -= optlen;
+    ip->ip_hl = hlen >> 2;
+    ip->ip_len -= optlen;
+    m->m_len -= optlen;
+  }
+
+  ip->ip_ttl = MAXTTL;
+  { /* swap */
+    struct in_addr icmp_dst;
+    icmp_dst = ip->ip_dst;
+    ip->ip_dst = ip->ip_src;
+    ip->ip_src = icmp_dst;
+  }
+
+  (void ) ip_output((struct socket *)NULL, m);
+
+  icmpstat.icps_reflect++;
+}