示例#1
0
void slirp_input(const uint8_t *pkt, int pkt_len)
{
    struct mbuf *m;
    int proto;

    if (pkt_len < ETH_HLEN)
        return;

    proto = ntohs(*(uint16_t *)(pkt + 12));
    switch(proto) {
    case ETH_P_ARP:
        arp_input(pkt, pkt_len);
        break;
    case ETH_P_IP:
        m = m_get();
        if (!m)
            return;
        
        if (M_FREEROOM(m) < pkt_len + 2) {
            m_inc(m, pkt_len + 2);
        }
        m->m_len = pkt_len + 2;
        memcpy(m->m_data + 2, pkt, pkt_len);

        m->m_data += 2 + ETH_HLEN;
        m->m_len -= 2 + ETH_HLEN;

        ip_input(m);
        break;
    default:
        break;
    }
}
示例#2
0
void
m_cat(struct mbuf *m, struct mbuf *n)
{
	if (M_FREEROOM(m) < n->m_len)
		m_inc(m,m->m_size+MINCSIZE);

	memcpy(m->m_data+m->m_len, n->m_data, n->m_len);
	m->m_len += n->m_len;

	m_free(n);
}
示例#3
0
/*
 * Copy data from one mbuf to the end of
 * the other.. if result is too big for one mbuf, malloc()
 * an M_EXT data segment
 */
void
m_cat(struct mbuf *m, struct mbuf *n)
{
	/*
	 * If there's no room, realloc
	 */
	if (M_FREEROOM(m) < n->m_len)
		m_inc(m,m->m_size+MINCSIZE);

	memcpy(m->m_data+m->m_len, n->m_data, n->m_len);
	m->m_len += n->m_len;

	m_free(n);
}
示例#4
0
文件: socket.c 项目: djs55/qemu
/*
 * recvfrom() a UDP socket
 */
void
sorecvfrom(struct socket *so)
{
	struct sockaddr_in addr;
	socklen_t addrlen = sizeof(struct sockaddr_in);

	DEBUG_CALL("sorecvfrom");
	DEBUG_ARG("so = %lx", (long)so);

	if (so->so_type == IPPROTO_ICMP) {   /* This is a "ping" reply */
	  char buff[256];
	  int len;

	  len = recvfrom(so->s, buff, 256, 0,
			 (struct sockaddr *)&addr, &addrlen);
	  /* XXX Check if reply is "correct"? */

	  if(len == -1 || len == 0) {
	    u_char code=ICMP_UNREACH_PORT;

	    if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
	    else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;

	    DEBUG_MISC((dfd," udp icmp rx errno = %d-%s\n",
			errno,strerror(errno)));
	    icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
	  } else {
	    icmp_reflect(so->so_m);
            so->so_m = NULL; /* Don't m_free() it again! */
	  }
	  /* No need for this socket anymore, udp_detach it */
	  udp_detach(so);
	} else {                            	/* A "normal" UDP packet */
	  struct mbuf *m;
          int len;
#ifdef _WIN32
          unsigned long n;
#else
          int n;
#endif

	  m = m_get(so->slirp);
	  if (!m) {
	      return;
	  }
	  m->m_data += IF_MAXLINKHDR;

	  /*
	   * XXX Shouldn't FIONREAD packets destined for port 53,
	   * but I don't know the max packet size for DNS lookups
	   */
	  len = M_FREEROOM(m);
	  /* if (so->so_fport != htons(53)) { */
	  ioctlsocket(so->s, FIONREAD, &n);

	  if (n > len) {
	    n = (m->m_data - m->m_dat) + m->m_len + n + 1;
	    m_inc(m, n);
	    len = M_FREEROOM(m);
	  }
	  /* } */

	  m->m_len = recvfrom(so->s, m->m_data, len, 0,
			      (struct sockaddr *)&addr, &addrlen);
	  DEBUG_MISC((dfd, " did recvfrom %d, errno = %d-%s\n",
		      m->m_len, errno,strerror(errno)));
	  if(m->m_len<0) {
	    u_char code=ICMP_UNREACH_PORT;

	    if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
	    else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;

	    DEBUG_MISC((dfd," rx error, tx icmp ICMP_UNREACH:%i\n", code));
	    icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
	    m_free(m);
	  } else {
	  /*
	   * Hack: domain name lookup will be used the most for UDP,
	   * and since they'll only be used once there's no need
	   * for the 4 minute (or whatever) timeout... So we time them
	   * out much quicker (10 seconds  for now...)
	   */
	    if (so->so_expire) {
	      if (so->so_fport == htons(53))
		so->so_expire = curtime + SO_EXPIREFAST;
	      else
		so->so_expire = curtime + SO_EXPIRE;
	    }

	    /*
	     * If this packet was destined for CTL_ADDR,
	     * make it look like that's where it came from, done by udp_output
	     */
	    udp_output(so, m, &addr);
	  } /* rx error */
	} /* if ping packet */
}
示例#5
0
文件: ip_icmp.c 项目: 0bliv10n/s2e
void
icmp_error(struct mbuf *msrc, u_char type, u_char code, int minsize,
           const 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 *);
#ifdef 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 */

  /* Do not reply to source-only IPs */
  if ((ip->ip_src.s_addr & htonl(~(0xf << 28))) == 0) {
      goto end_error;
  }

  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 */
  m = m_get(msrc->slirp);
  if (!m) {
      goto end_error;
  }

  { 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);

#ifdef 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 = m->slirp->vhost_addr;

  (void ) ip_output((struct socket *)NULL, m);

end_error:
  return;
}
示例#6
0
 self &    operator++() { m_inc(); return *this; }
示例#7
0
文件: socket.c 项目: m000/panda
/*
 * recvfrom() a UDP socket
 */
void
sorecvfrom(struct socket *so)
{
	struct sockaddr_storage addr;
	struct sockaddr_storage saddr, daddr;
	socklen_t addrlen = sizeof(struct sockaddr_storage);

	DEBUG_CALL("sorecvfrom");
	DEBUG_ARG("so = %p", so);

	if (so->so_type == IPPROTO_ICMP) {   /* This is a "ping" reply */
	  char buff[256];
	  int len;

	  len = recvfrom(so->s, buff, 256, 0,
			 (struct sockaddr *)&addr, &addrlen);
	  /* XXX Check if reply is "correct"? */

	  if(len == -1 || len == 0) {
	    u_char code=ICMP_UNREACH_PORT;

	    if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
	    else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;

	    DEBUG_MISC((dfd," udp icmp rx errno = %d-%s\n",
			errno,strerror(errno)));
	    icmp_send_error(so->so_m, ICMP_UNREACH, code, 0, strerror(errno));
	  } else {
	    icmp_reflect(so->so_m);
            so->so_m = NULL; /* Don't m_free() it again! */
	  }
	  /* No need for this socket anymore, udp_detach it */
	  udp_detach(so);
	} else {                            	/* A "normal" UDP packet */
	  struct mbuf *m;
          int len;
#ifdef _WIN32
          unsigned long n;
#else
          int n;
#endif

	  m = m_get(so->slirp);
	  if (!m) {
	      return;
	  }
	  switch (so->so_ffamily) {
	  case AF_INET:
	      m->m_data += IF_MAXLINKHDR + sizeof(struct udpiphdr);
	      break;
	  case AF_INET6:
	      m->m_data += IF_MAXLINKHDR + sizeof(struct ip6)
	                                 + sizeof(struct udphdr);
	      break;
	  default:
	      g_assert_not_reached();
	      break;
	  }

	  /*
	   * XXX Shouldn't FIONREAD packets destined for port 53,
	   * but I don't know the max packet size for DNS lookups
	   */
	  len = M_FREEROOM(m);
	  /* if (so->so_fport != htons(53)) { */
	  ioctlsocket(so->s, FIONREAD, &n);

	  if (n > len) {
	    n = (m->m_data - m->m_dat) + m->m_len + n + 1;
	    m_inc(m, n);
	    len = M_FREEROOM(m);
	  }
	  /* } */

	  m->m_len = recvfrom(so->s, m->m_data, len, 0,
			      (struct sockaddr *)&addr, &addrlen);
	  DEBUG_MISC((dfd, " did recvfrom %d, errno = %d-%s\n",
		      m->m_len, errno,strerror(errno)));
	  if(m->m_len<0) {
	    /* Report error as ICMP */
	    switch (so->so_lfamily) {
	    uint8_t code;
	    case AF_INET:
	      code = ICMP_UNREACH_PORT;

	      if (errno == EHOSTUNREACH) {
		code = ICMP_UNREACH_HOST;
	      } else if (errno == ENETUNREACH) {
		code = ICMP_UNREACH_NET;
	      }

	      DEBUG_MISC((dfd, " rx error, tx icmp ICMP_UNREACH:%i\n", code));
	      icmp_send_error(so->so_m, ICMP_UNREACH, code, 0, strerror(errno));
	      break;
	    case AF_INET6:
	      code = ICMP6_UNREACH_PORT;

	      if (errno == EHOSTUNREACH) {
		code = ICMP6_UNREACH_ADDRESS;
	      } else if (errno == ENETUNREACH) {
		code = ICMP6_UNREACH_NO_ROUTE;
	      }

	      DEBUG_MISC((dfd, " rx error, tx icmp6 ICMP_UNREACH:%i\n", code));
	      icmp6_send_error(so->so_m, ICMP6_UNREACH, code);
	      break;
	    default:
	      g_assert_not_reached();
	      break;
	    }
	    m_free(m);
	  } else {
	  /*
	   * Hack: domain name lookup will be used the most for UDP,
	   * and since they'll only be used once there's no need
	   * for the 4 minute (or whatever) timeout... So we time them
	   * out much quicker (10 seconds  for now...)
	   */
	    if (so->so_expire) {
	      if (so->so_fport == htons(53))
		so->so_expire = curtime + SO_EXPIREFAST;
	      else
		so->so_expire = curtime + SO_EXPIRE;
	    }

	    /*
	     * If this packet was destined for CTL_ADDR,
	     * make it look like that's where it came from
	     */
	    saddr = addr;
	    sotranslate_in(so, &saddr);
	    daddr = so->lhost.ss;

	    switch (so->so_ffamily) {
	    case AF_INET:
	        udp_output(so, m, (struct sockaddr_in *) &saddr,
	                   (struct sockaddr_in *) &daddr,
	                   so->so_iptos);
	        break;
	    case AF_INET6:
	        udp6_output(so, m, (struct sockaddr_in6 *) &saddr,
	                    (struct sockaddr_in6 *) &daddr);
	        break;
	    default:
	        g_assert_not_reached();
	        break;
	    }
	  } /* rx error */
	} /* if ping packet */
}