Пример #1
0
static DBusMessage *dbus_reply_server_loop(DBusMessage *message)
{
  DBusMessageIter args, args_iter;
  struct server *serv;
  DBusMessage *reply = dbus_message_new_method_return(message);
   
  dbus_message_iter_init_append (reply, &args);
  dbus_message_iter_open_container (&args, DBUS_TYPE_ARRAY,DBUS_TYPE_STRING_AS_STRING, &args_iter);

  for (serv = daemon->servers; serv; serv = serv->next)
    if (serv->flags & SERV_LOOP)
      {
	prettyprint_addr(&serv->addr, daemon->addrbuff);
	dbus_message_iter_append_basic (&args_iter, DBUS_TYPE_STRING, &daemon->addrbuff);
      }
  
  dbus_message_iter_close_container (&args, &args_iter);

  return reply;
}
Пример #2
0
static size_t process_reply(HEADER *header, time_t now, 
			    struct server *server, size_t n)
{
  unsigned char *pheader, *sizep;
  int munged = 0, is_sign;
  size_t plen; 

  /* If upstream is advertising a larger UDP packet size
     than we allow, trim it so that we don't get overlarge
     requests for the client. We can't do this for signed packets. */

  if ((pheader = find_pseudoheader(header, n, &plen, &sizep, &is_sign)) && !is_sign)
    {
      unsigned short udpsz;
      unsigned char *psave = sizep;
      
      GETSHORT(udpsz, sizep);
      if (udpsz > daemon->edns_pktsz)
	PUTSHORT(daemon->edns_pktsz, psave);
    }

  if (header->opcode != QUERY || (header->rcode != NOERROR && header->rcode != NXDOMAIN))
    return n;
  
  /* Complain loudly if the upstream server is non-recursive. */
  if (!header->ra && header->rcode == NOERROR && ntohs(header->ancount) == 0 &&
      server && !(server->flags & SERV_WARNED_RECURSIVE))
    {
      prettyprint_addr(&server->addr, daemon->namebuff);
      my_syslog(LOG_WARNING, _("nameserver %s refused to do a recursive query"), daemon->namebuff);
      if (!(daemon->options & OPT_LOG))
	server->flags |= SERV_WARNED_RECURSIVE;
    }  
    
  if (daemon->bogus_addr && header->rcode != NXDOMAIN &&
      check_for_bogus_wildcard(header, n, daemon->namebuff, daemon->bogus_addr, now))
    {
      munged = 1;
      header->rcode = NXDOMAIN;
      header->aa = 0;
    }
  else 
    {
      if (header->rcode == NXDOMAIN && 
	  extract_request(header, n, daemon->namebuff, NULL) &&
	  check_for_local_domain(daemon->namebuff, now))
	{
	  /* if we forwarded a query for a locally known name (because it was for 
	     an unknown type) and the answer is NXDOMAIN, convert that to NODATA,
	     since we know that the domain exists, even if upstream doesn't */
	  munged = 1;
	  header->aa = 1;
	  header->rcode = NOERROR;
	}
      
      if (extract_addresses(header, n, daemon->namebuff, now))
	{
	  my_syslog(LOG_WARNING, _("possible DNS-rebind attack detected"));
	  munged = 1;
	}
    }
  
  /* do this after extract_addresses. Ensure NODATA reply and remove
     nameserver info. */
  
  if (munged)
    {
      header->ancount = htons(0);
      header->nscount = htons(0);
      header->arcount = htons(0);
    }
  
  /* the bogus-nxdomain stuff, doctor and NXDOMAIN->NODATA munging can all elide
     sections of the packet. Find the new length here and put back pseudoheader
     if it was removed. */
  return resize_packet(header, n, pheader, plen);
}
Пример #3
0
void check_tftp_listeners(time_t now)
{
  struct tftp_transfer *transfer, *tmp, **up;
  ssize_t len;
  
  struct ack {
    unsigned short op, block;
  } *mess = (struct ack *)daemon->packet;
  
  /* Check for activity on any existing transfers */
  for (transfer = daemon->tftp_trans, up = &daemon->tftp_trans; transfer; transfer = tmp)
    {
      tmp = transfer->next;
      
      prettyprint_addr(&transfer->peer, daemon->addrbuff);
     
      if (poll_check(transfer->sockfd, POLLIN))
	{
	  /* we overwrote the buffer... */
	  daemon->srv_save = NULL;
	  
	  if ((len = recv(transfer->sockfd, daemon->packet, daemon->packet_buff_sz, 0)) >= (ssize_t)sizeof(struct ack))
	    {
	      if (ntohs(mess->op) == OP_ACK && ntohs(mess->block) == (unsigned short)transfer->block) 
		{
		  /* Got ack, ensure we take the (re)transmit path */
		  transfer->timeout = now;
		  transfer->backoff = 0;
		  if (transfer->block++ != 0)
		    transfer->offset += transfer->blocksize - transfer->expansion;
		}
	      else if (ntohs(mess->op) == OP_ERR)
		{
		  char *p = daemon->packet + sizeof(struct ack);
		  char *end = daemon->packet + len;
		  char *err = next(&p, end);
		  
		  /* Sanitise error message */
		  if (!err)
		    err = "";
		  else
		    sanitise(err);
		  
		  my_syslog(MS_TFTP | LOG_ERR, _("error %d %s received from %s"),
			    (int)ntohs(mess->block), err, 
			    daemon->addrbuff);	
		  
		  /* Got err, ensure we take abort */
		  transfer->timeout = now;
		  transfer->backoff = 100;
		}
	    }
	}
      
      if (difftime(now, transfer->timeout) >= 0.0)
	{
	  int endcon = 0;

	  /* timeout, retransmit */
	  transfer->timeout += 1 + (1<<transfer->backoff);
	  	  
	  /* we overwrote the buffer... */
	  daemon->srv_save = NULL;
	 
	  if ((len = get_block(daemon->packet, transfer)) == -1)
	    {
	      len = tftp_err_oops(daemon->packet, transfer->file->filename);
	      endcon = 1;
	    }
	  /* don't complain about timeout when we're awaiting the last
	     ACK, some clients never send it */
	  else if (++transfer->backoff > 7 && len != 0)
	    {
	      endcon = 1;
	      len = 0;
	    }

	  if (len != 0)
	    while(sendto(transfer->sockfd, daemon->packet, len, 0, 
			 (struct sockaddr *)&transfer->peer, sa_len(&transfer->peer)) == -1 && errno == EINTR);
	  
	  if (endcon || len == 0)
	    {
	      strcpy(daemon->namebuff, transfer->file->filename);
	      sanitise(daemon->namebuff);
	      my_syslog(MS_TFTP | LOG_INFO, endcon ? _("failed sending %s to %s") : _("sent %s to %s"), daemon->namebuff, daemon->addrbuff);
	      /* unlink */
	      *up = tmp;
	      if (endcon)
		free_transfer(transfer);
	      else
		{
		  /* put on queue to be sent to script and deleted */
		  transfer->next = daemon->tftp_done_trans;
		  daemon->tftp_done_trans = transfer;
		}
	      continue;
	    }
	}

      up = &transfer->next;
    }    
}
Пример #4
0
void tftp_request(struct listener *listen, time_t now)
{
  ssize_t len;
  char *packet = daemon->packet;
  char *filename, *mode, *p, *end, *opt;
  union mysockaddr addr, peer;
  struct msghdr msg;
  struct iovec iov;
  struct ifreq ifr;
  int is_err = 1, if_index = 0, mtu = 0;
  struct iname *tmp;
  struct tftp_transfer *transfer;
  int port = daemon->start_tftp_port; /* may be zero to use ephemeral port */
#if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DONT)
  int mtuflag = IP_PMTUDISC_DONT;
#endif
  char namebuff[IF_NAMESIZE];
  char *name = NULL;
  char *prefix = daemon->tftp_prefix;
  struct tftp_prefix *pref;
  union all_addr addra;
  /* Can always get recvd interface for IPv6 */
  int check_dest = !option_bool(OPT_NOWILD) || listen->family == AF_INET6;
  union {
    struct cmsghdr align; /* this ensures alignment */
    char control6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
#if defined(HAVE_LINUX_NETWORK)
    char control[CMSG_SPACE(sizeof(struct in_pktinfo))];
#elif defined(HAVE_SOLARIS_NETWORK)
    char control[CMSG_SPACE(sizeof(unsigned int))];
#elif defined(IP_RECVDSTADDR) && defined(IP_RECVIF)
    char control[CMSG_SPACE(sizeof(struct sockaddr_dl))];
#endif
  } control_u; 

  msg.msg_controllen = sizeof(control_u);
  msg.msg_control = control_u.control;
  msg.msg_flags = 0;
  msg.msg_name = &peer;
  msg.msg_namelen = sizeof(peer);
  msg.msg_iov = &iov;
  msg.msg_iovlen = 1;

  iov.iov_base = packet;
  iov.iov_len = daemon->packet_buff_sz;

  /* we overwrote the buffer... */
  daemon->srv_save = NULL;

  if ((len = recvmsg(listen->tftpfd, &msg, 0)) < 2)
    return;

  /* Can always get recvd interface for IPv6 */
  if (!check_dest)
    {
      if (listen->iface)
	{
	  addr = listen->iface->addr;
	  name = listen->iface->name;
	  mtu = listen->iface->mtu;
	  if (daemon->tftp_mtu != 0 && daemon->tftp_mtu < mtu)
	    mtu = daemon->tftp_mtu;
	}
      else
	{
	  /* we're listening on an address that doesn't appear on an interface,
	     ask the kernel what the socket is bound to */
	  socklen_t tcp_len = sizeof(union mysockaddr);
	  if (getsockname(listen->tftpfd, (struct sockaddr *)&addr, &tcp_len) == -1)
	    return;
	}
    }
  else
    {
      struct cmsghdr *cmptr;

      if (msg.msg_controllen < sizeof(struct cmsghdr))
        return;
      
      addr.sa.sa_family = listen->family;
      
#if defined(HAVE_LINUX_NETWORK)
      if (listen->family == AF_INET)
	for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
	  if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO)
	    {
	      union {
		unsigned char *c;
		struct in_pktinfo *p;
	      } p;
	      p.c = CMSG_DATA(cmptr);
	      addr.in.sin_addr = p.p->ipi_spec_dst;
	      if_index = p.p->ipi_ifindex;
	    }
      
#elif defined(HAVE_SOLARIS_NETWORK)
      if (listen->family == AF_INET)
	for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
	  {
	    union {
	      unsigned char *c;
	      struct in_addr *a;
	      unsigned int *i;
	    } p;
	    p.c = CMSG_DATA(cmptr);
	    if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVDSTADDR)
	    addr.in.sin_addr = *(p.a);
	    else if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVIF)
	    if_index = *(p.i);
	  }
      
#elif defined(IP_RECVDSTADDR) && defined(IP_RECVIF)
      if (listen->family == AF_INET)
	for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
	  {
	    union {
	      unsigned char *c;
	      struct in_addr *a;
	      struct sockaddr_dl *s;
	    } p;
	    p.c = CMSG_DATA(cmptr);
	    if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVDSTADDR)
	      addr.in.sin_addr = *(p.a);
	    else if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVIF)
	      if_index = p.s->sdl_index;
	  }
	  
#endif

      if (listen->family == AF_INET6)
        {
          for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
            if (cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == daemon->v6pktinfo)
              {
                union {
                  unsigned char *c;
                  struct in6_pktinfo *p;
                } p;
                p.c = CMSG_DATA(cmptr);
                  
                addr.in6.sin6_addr = p.p->ipi6_addr;
                if_index = p.p->ipi6_ifindex;
              }
        }
      
      if (!indextoname(listen->tftpfd, if_index, namebuff))
	return;

      name = namebuff;
      
      addra.addr4 = addr.in.sin_addr;

      if (listen->family == AF_INET6)
	addra.addr6 = addr.in6.sin6_addr;

      if (daemon->tftp_interfaces)
	{
	  /* dedicated tftp interface list */
	  for (tmp = daemon->tftp_interfaces; tmp; tmp = tmp->next)
	    if (tmp->name && wildcard_match(tmp->name, name))
	      break;

	  if (!tmp)
	    return;
	}
      else
	{
	  /* Do the same as DHCP */
	  if (!iface_check(listen->family, &addra, name, NULL))
	    {
	      if (!option_bool(OPT_CLEVERBIND))
		enumerate_interfaces(0); 
	      if (!loopback_exception(listen->tftpfd, listen->family, &addra, name) &&
		  !label_exception(if_index, listen->family, &addra))
		return;
	    }
	  
#ifdef HAVE_DHCP      
	  /* allowed interfaces are the same as for DHCP */
	  for (tmp = daemon->dhcp_except; tmp; tmp = tmp->next)
	    if (tmp->name && wildcard_match(tmp->name, name))
	      return;
#endif
	}

      safe_strncpy(ifr.ifr_name, name, IF_NAMESIZE);
      if (ioctl(listen->tftpfd, SIOCGIFMTU, &ifr) != -1)
	{
	  mtu = ifr.ifr_mtu;  
	  if (daemon->tftp_mtu != 0 && daemon->tftp_mtu < mtu)
	    mtu = daemon->tftp_mtu;    
	}
    }

  /* Failed to get interface mtu - can use configured value. */
  if (mtu == 0)
    mtu = daemon->tftp_mtu;

  if (name)
    {
      /* check for per-interface prefix */ 
      for (pref = daemon->if_prefix; pref; pref = pref->next)
	if (strcmp(pref->interface, name) == 0)
	  prefix = pref->prefix;  
    }

  if (listen->family == AF_INET)
    {
      addr.in.sin_port = htons(port);
#ifdef HAVE_SOCKADDR_SA_LEN
      addr.in.sin_len = sizeof(addr.in);
#endif
    }
  else
    {
      addr.in6.sin6_port = htons(port);
      addr.in6.sin6_flowinfo = 0;
      addr.in6.sin6_scope_id = 0;
#ifdef HAVE_SOCKADDR_SA_LEN
      addr.in6.sin6_len = sizeof(addr.in6);
#endif
    }

  if (!(transfer = whine_malloc(sizeof(struct tftp_transfer))))
    return;
  
  if ((transfer->sockfd = socket(listen->family, SOCK_DGRAM, 0)) == -1)
    {
      free(transfer);
      return;
    }
  
  transfer->peer = peer;
  transfer->timeout = now + 2;
  transfer->backoff = 1;
  transfer->block = 1;
  transfer->blocksize = 512;
  transfer->offset = 0;
  transfer->file = NULL;
  transfer->opt_blocksize = transfer->opt_transize = 0;
  transfer->netascii = transfer->carrylf = 0;
 
  prettyprint_addr(&peer, daemon->addrbuff);
  
  /* if we have a nailed-down range, iterate until we find a free one. */
  while (1)
    {
      if (bind(transfer->sockfd, &addr.sa, sa_len(&addr)) == -1 ||
#if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DONT)
	  setsockopt(transfer->sockfd, IPPROTO_IP, IP_MTU_DISCOVER, &mtuflag, sizeof(mtuflag)) == -1 ||
#endif
	  !fix_fd(transfer->sockfd))
	{
	  if (errno == EADDRINUSE && daemon->start_tftp_port != 0)
	    {
	      if (++port <= daemon->end_tftp_port)
		{ 
		  if (listen->family == AF_INET)
		    addr.in.sin_port = htons(port);
		  else
		    addr.in6.sin6_port = htons(port);
		  
		  continue;
		}
	      my_syslog(MS_TFTP | LOG_ERR, _("unable to get free port for TFTP"));
	    }
	  free_transfer(transfer);
	  return;
	}
      break;
    }
  
  p = packet + 2;
  end = packet + len;

  if (ntohs(*((unsigned short *)packet)) != OP_RRQ ||
      !(filename = next(&p, end)) ||
      !(mode = next(&p, end)) ||
      (strcasecmp(mode, "octet") != 0 && strcasecmp(mode, "netascii") != 0))
    {
      len = tftp_err(ERR_ILL, packet, _("unsupported request from %s"), daemon->addrbuff);
      is_err = 1;
    }
  else
    {
      if (strcasecmp(mode, "netascii") == 0)
	transfer->netascii = 1;
      
      while ((opt = next(&p, end)))
	{
	  if (strcasecmp(opt, "blksize") == 0)
	    {
	      if ((opt = next(&p, end)) && !option_bool(OPT_TFTP_NOBLOCK))
		{
		  /* 32 bytes for IP, UDP and TFTP headers, 52 bytes for IPv6 */
		  int overhead = (listen->family == AF_INET) ? 32 : 52;
		  transfer->blocksize = atoi(opt);
		  if (transfer->blocksize < 1)
		    transfer->blocksize = 1;
		  if (transfer->blocksize > (unsigned)daemon->packet_buff_sz - 4)
		    transfer->blocksize = (unsigned)daemon->packet_buff_sz - 4;
		  if (mtu != 0 && transfer->blocksize > (unsigned)mtu - overhead)
		    transfer->blocksize = (unsigned)mtu - overhead;
		  transfer->opt_blocksize = 1;
		  transfer->block = 0;
		}
	    }
	  else if (strcasecmp(opt, "tsize") == 0 && next(&p, end) && !transfer->netascii)
	    {
	      transfer->opt_transize = 1;
	      transfer->block = 0;
	    }
	}

      /* cope with backslashes from windows boxen. */
      for (p = filename; *p; p++)
	if (*p == '\\')
	  *p = '/';
	else if (option_bool(OPT_TFTP_LC))
	  *p = tolower(*p);
		
      strcpy(daemon->namebuff, "/");
      if (prefix)
	{
	  if (prefix[0] == '/')
	    daemon->namebuff[0] = 0;
	  strncat(daemon->namebuff, prefix, (MAXDNAME-1) - strlen(daemon->namebuff));
	  if (prefix[strlen(prefix)-1] != '/')
	    strncat(daemon->namebuff, "/", (MAXDNAME-1) - strlen(daemon->namebuff));

	  if (option_bool(OPT_TFTP_APREF_IP))
	    {
	      size_t oldlen = strlen(daemon->namebuff);
	      struct stat statbuf;
	      
	      strncat(daemon->namebuff, daemon->addrbuff, (MAXDNAME-1) - strlen(daemon->namebuff));
	      strncat(daemon->namebuff, "/", (MAXDNAME-1) - strlen(daemon->namebuff));
	      
	      /* remove unique-directory if it doesn't exist */
	      if (stat(daemon->namebuff, &statbuf) == -1 || !S_ISDIR(statbuf.st_mode))
		daemon->namebuff[oldlen] = 0;
	    }
	  
	  if (option_bool(OPT_TFTP_APREF_MAC))
	    {
	      unsigned char *macaddr = NULL;
	      unsigned char macbuf[DHCP_CHADDR_MAX];
	      
#ifdef HAVE_DHCP
	      if (daemon->dhcp && peer.sa.sa_family == AF_INET)
	        {
		  /* Check if the client IP is in our lease database */
		  struct dhcp_lease *lease = lease_find_by_addr(peer.in.sin_addr);
		  if (lease && lease->hwaddr_type == ARPHRD_ETHER && lease->hwaddr_len == ETHER_ADDR_LEN)
		    macaddr = lease->hwaddr;
		}
#endif
	      
	      /* If no luck, try to find in ARP table. This only works if client is in same (V)LAN */
	      if (!macaddr && find_mac(&peer, macbuf, 1, now) > 0)
		macaddr = macbuf;
	      
	      if (macaddr)
	        {
		  size_t oldlen = strlen(daemon->namebuff);
		  struct stat statbuf;

		  snprintf(daemon->namebuff + oldlen, (MAXDNAME-1) - oldlen, "%.2x-%.2x-%.2x-%.2x-%.2x-%.2x/",
			   macaddr[0], macaddr[1], macaddr[2], macaddr[3], macaddr[4], macaddr[5]);
		  
		  /* remove unique-directory if it doesn't exist */
		  if (stat(daemon->namebuff, &statbuf) == -1 || !S_ISDIR(statbuf.st_mode))
		    daemon->namebuff[oldlen] = 0;
		}
	    }
	  
	  /* Absolute pathnames OK if they match prefix */
	  if (filename[0] == '/')
	    {
	      if (strstr(filename, daemon->namebuff) == filename)
		daemon->namebuff[0] = 0;
	      else
		filename++;
	    }
	}
      else if (filename[0] == '/')
	daemon->namebuff[0] = 0;
      strncat(daemon->namebuff, filename, (MAXDNAME-1) - strlen(daemon->namebuff));
      
      /* check permissions and open file */
      if ((transfer->file = check_tftp_fileperm(&len, prefix)))
	{
	  if ((len = get_block(packet, transfer)) == -1)
	    len = tftp_err_oops(packet, daemon->namebuff);
	  else
	    is_err = 0;
	}
    }
  
  while (sendto(transfer->sockfd, packet, len, 0, 
		(struct sockaddr *)&peer, sa_len(&peer)) == -1 && errno == EINTR);
  
  if (is_err)
    free_transfer(transfer);
  else
    {
      transfer->next = daemon->tftp_trans;
      daemon->tftp_trans = transfer;
    }
}
Пример #5
0
void check_tftp_listeners(fd_set *rset, time_t now)
{
  struct tftp_transfer *transfer, *tmp, **up;
  ssize_t len;
  char pretty_addr[ADDRSTRLEN];
  
  struct ack {
    unsigned short op, block;
  } *mess = (struct ack *)daemon->packet;
  
  /* Check for activity on any existing transfers */
  for (transfer = daemon->tftp_trans, up = &daemon->tftp_trans; transfer; transfer = tmp)
    {
      tmp = transfer->next;
      
      if (FD_ISSET(transfer->sockfd, rset))
	{
	  /* we overwrote the buffer... */
	  daemon->srv_save = NULL;
	   
	  prettyprint_addr(&transfer->peer, pretty_addr);
	  
	  if ((len = recv(transfer->sockfd, daemon->packet, daemon->packet_buff_sz, 0)) >= (ssize_t)sizeof(struct ack))
	    {
	      if (ntohs(mess->op) == OP_ACK && ntohs(mess->block) == (unsigned short)transfer->block) 
		{
		  /* Got ack, ensure we take the (re)transmit path */
		  transfer->timeout = now;
		  transfer->backoff = 0;
		  if (transfer->block++ != 0)
		    transfer->offset += transfer->blocksize - transfer->expansion;
		}
	      else if (ntohs(mess->op) == OP_ERR)
		{
		  char *p = daemon->packet + sizeof(struct ack);
		  char *end = daemon->packet + len;
		  char *err = next(&p, end);
		  
		  /* Sanitise error message */
		  if (!err)
		    err = "";
		  else
		    {
		      char *q, *r;
		      for (q = r = err; *r; r++)
			if (isprint((int)*r))
			  *(q++) = *r;
		      *q = 0;
		    }

		  my_syslog(MS_TFTP | LOG_ERR, _("error %d %s received from %s"),
			    (int)ntohs(mess->block), err, 
			    pretty_addr);	
		  
		  /* Got err, ensure we take abort */
		  transfer->timeout = now;
		  transfer->backoff = 100;
		}
	    }
	}
      
      if (difftime(now, transfer->timeout) >= 0.0)
	{
	  int endcon = 0;

	  /* timeout, retransmit */
	  transfer->timeout += 1 + (1<<transfer->backoff);
	  	  
	  /* we overwrote the buffer... */
	  daemon->srv_save = NULL;
	 
	  if ((len = get_block(daemon->packet, transfer)) == -1)
	    {
	      len = tftp_err_oops(daemon->packet, transfer->file->filename);
	      endcon = 1;
	    }
	  else if (++transfer->backoff > 5)
	    {
	      /* don't complain about timeout when we're awaiting the last
		 ACK, some clients never send it */
	      if (len != 0)
		{
		  my_syslog(MS_TFTP | LOG_ERR, _("failed sending %s to %s"), 
			    transfer->file->filename, pretty_addr);
		  len = 0;
		  endcon = 1;
		}
	    }
	  
	  if (len != 0)
	    while(sendto(transfer->sockfd, daemon->packet, len, 0, 
			 (struct sockaddr *)&transfer->peer, sizeof(transfer->peer)) == -1 && errno == EINTR);
	  
	  if (endcon || len == 0)
	    {
	      if (!endcon)
		my_syslog(MS_TFTP | LOG_INFO, _("sent %s to %s"), transfer->file->filename, pretty_addr);
	      /* unlink */
	      *up = tmp;
	      free_transfer(transfer);
	      continue;
	    }
	}

      up = &transfer->next;
    }    
}
Пример #6
0
void tftp_request(struct listener *listen, time_t now)
{
  ssize_t len;
  char *packet = daemon->packet;
  char *filename, *mode, *p, *end, *opt;
  union mysockaddr addr, peer;
  struct msghdr msg;
  struct iovec iov;
  struct ifreq ifr;
  int is_err = 1, if_index = 0, mtu = 0, special = 0;
#ifdef HAVE_DHCP
  struct iname *tmp;
#endif
  struct tftp_transfer *transfer;
  int port = daemon->start_tftp_port; /* may be zero to use ephemeral port */
#if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DONT)
  int mtuflag = IP_PMTUDISC_DONT;
#endif
  char namebuff[IF_NAMESIZE];
  char pretty_addr[ADDRSTRLEN];
  char *name;
  char *prefix = daemon->tftp_prefix;
  struct tftp_prefix *pref;
  struct interface_list *ir;

  union {
    struct cmsghdr align; /* this ensures alignment */
#ifdef HAVE_IPV6
    char control6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
#endif
#if defined(HAVE_LINUX_NETWORK)
    char control[CMSG_SPACE(sizeof(struct in_pktinfo))];
#elif defined(HAVE_SOLARIS_NETWORK)
    char control[CMSG_SPACE(sizeof(unsigned int))];
#elif defined(IP_RECVDSTADDR) && defined(IP_RECVIF)
    char control[CMSG_SPACE(sizeof(struct sockaddr_dl))];
#endif
  } control_u; 

  msg.msg_controllen = sizeof(control_u);
  msg.msg_control = control_u.control;
  msg.msg_flags = 0;
  msg.msg_name = &peer;
  msg.msg_namelen = sizeof(peer);
  msg.msg_iov = &iov;
  msg.msg_iovlen = 1;

  iov.iov_base = packet;
  iov.iov_len = daemon->packet_buff_sz;

  /* we overwrote the buffer... */
  daemon->srv_save = NULL;

  if ((len = recvmsg(listen->tftpfd, &msg, 0)) < 2)
    return;
  
  if (option_bool(OPT_NOWILD))
    {
      addr = listen->iface->addr;
      mtu = listen->iface->mtu;
      name = listen->iface->name;
    }
  else
    {
      struct cmsghdr *cmptr;
      int check;
      struct interface_list *ir;

      if (msg.msg_controllen < sizeof(struct cmsghdr))
        return;
      
      addr.sa.sa_family = listen->family;
      
#if defined(HAVE_LINUX_NETWORK)
      if (listen->family == AF_INET)
	for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
	  if (cmptr->cmsg_level == SOL_IP && cmptr->cmsg_type == IP_PKTINFO)
	    {
	      union {
		unsigned char *c;
		struct in_pktinfo *p;
	      } p;
	      p.c = CMSG_DATA(cmptr);
	      addr.in.sin_addr = p.p->ipi_spec_dst;
	      if_index = p.p->ipi_ifindex;
	    }
      
#elif defined(HAVE_SOLARIS_NETWORK)
      if (listen->family == AF_INET)
	for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
	  {
	    union {
	      unsigned char *c;
	      struct in_addr *a;
	      unsigned int *i;
	    } p;
	    p.c = CMSG_DATA(cmptr);
	    if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVDSTADDR)
	    addr.in.sin_addr = *(p.a);
	    else if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVIF)
	    if_index = *(p.i);
	  }
      
#elif defined(IP_RECVDSTADDR) && defined(IP_RECVIF)
      if (listen->family == AF_INET)
	for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
	  {
	    union {
	      unsigned char *c;
	      struct in_addr *a;
	      struct sockaddr_dl *s;
	    } p;
	    p.c = CMSG_DATA(cmptr);
	    if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVDSTADDR)
	      addr.in.sin_addr = *(p.a);
	    else if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVIF)
	      if_index = p.s->sdl_index;
	  }
	  
#endif

#ifdef HAVE_IPV6
      if (listen->family == AF_INET6)
        {
          for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
            if (cmptr->cmsg_level == IPV6_LEVEL && cmptr->cmsg_type == daemon->v6pktinfo)
              {
                union {
                  unsigned char *c;
                  struct in6_pktinfo *p;
                } p;
                p.c = CMSG_DATA(cmptr);
                  
                addr.in6.sin6_addr = p.p->ipi6_addr;
                if_index = p.p->ipi6_ifindex;
              }
        }
#endif
      
      if (!indextoname(listen->tftpfd, if_index, namebuff))
	return;

      name = namebuff;

#ifdef HAVE_IPV6
      if (listen->family == AF_INET6)
	check = iface_check(AF_INET6, (struct all_addr *)&addr.in6.sin6_addr, name, &if_index);
      else
#endif
        check = iface_check(AF_INET, (struct all_addr *)&addr.in.sin_addr, name, &if_index);

      /* wierd TFTP service override */
      for (ir = daemon->tftp_interfaces; ir; ir = ir->next)
	if (strcmp(ir->interface, name) == 0)
	  break;
       
      if (!ir)
	{
	  if (!daemon->tftp_unlimited || !check)
	    return;
	  
#ifdef HAVE_DHCP      
	  /* allowed interfaces are the same as for DHCP */
	  for (tmp = daemon->dhcp_except; tmp; tmp = tmp->next)
	    if (tmp->name && (strcmp(tmp->name, name) == 0))
	      return;
#endif
	}

      strncpy(ifr.ifr_name, name, IF_NAMESIZE);
      if (ioctl(listen->tftpfd, SIOCGIFMTU, &ifr) != -1)
	mtu = ifr.ifr_mtu;      
    }
  
  /* check for per-interface prefix */ 
  for (pref = daemon->if_prefix; pref; pref = pref->next)
    if (strcmp(pref->interface, name) == 0)
      prefix = pref->prefix;

  /* wierd TFTP interfaces disable special options. */
  for (ir = daemon->tftp_interfaces; ir; ir = ir->next)
    if (strcmp(ir->interface, name) == 0)
      special = 1;

#ifdef HAVE_SOCKADDR_SA_LEN
  addr.sa.sa_len = sa_len(&addr);
#endif

  if (listen->family == AF_INET)
    addr.in.sin_port = htons(port);
#ifdef HAVE_IPV6
  else
    {
      addr.in6.sin6_port = htons(port);
      addr.in6.sin6_flowinfo = 0;
    }
#endif

  if (!(transfer = whine_malloc(sizeof(struct tftp_transfer))))
    return;
  
  if ((transfer->sockfd = socket(listen->family, SOCK_DGRAM, 0)) == -1)
    {
      free(transfer);
      return;
    }
  
  transfer->peer = peer;
  transfer->timeout = now + 2;
  transfer->backoff = 1;
  transfer->block = 1;
  transfer->blocksize = 512;
  transfer->offset = 0;
  transfer->file = NULL;
  transfer->opt_blocksize = transfer->opt_transize = 0;
  transfer->netascii = transfer->carrylf = 0;
 
  prettyprint_addr(&peer, pretty_addr);
  
  /* if we have a nailed-down range, iterate until we find a free one. */
  while (1)
    {
      if (bind(transfer->sockfd, &addr.sa, sizeof(addr)) == -1 ||
#if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DONT)
	  setsockopt(transfer->sockfd, SOL_IP, IP_MTU_DISCOVER, &mtuflag, sizeof(mtuflag)) == -1 ||
#endif
	  !fix_fd(transfer->sockfd))
	{
	  if (errno == EADDRINUSE && daemon->start_tftp_port != 0)
	    {
	      if (++port <= daemon->end_tftp_port)
		{ 
		  if (listen->family == AF_INET)
		    addr.in.sin_port = htons(port);
#ifdef HAVE_IPV6
		  else
		     addr.in6.sin6_port = htons(port);
#endif
		  continue;
		}
	      my_syslog(MS_TFTP | LOG_ERR, _("unable to get free port for TFTP"));
	    }
	  free_transfer(transfer);
	  return;
	}
      break;
    }
  
  p = packet + 2;
  end = packet + len;

  if (ntohs(*((unsigned short *)packet)) != OP_RRQ ||
      !(filename = next(&p, end)) ||
      !(mode = next(&p, end)) ||
      (strcasecmp(mode, "octet") != 0 && strcasecmp(mode, "netascii") != 0))
    len = tftp_err(ERR_ILL, packet, _("unsupported request from %s"), pretty_addr);
  else
    {
      if (strcasecmp(mode, "netascii") == 0)
	transfer->netascii = 1;
      
      while ((opt = next(&p, end)))
	{
	  if (strcasecmp(opt, "blksize") == 0)
	    {
	      if ((opt = next(&p, end)) &&
		  (special || !option_bool(OPT_TFTP_NOBLOCK)))
		{
		  transfer->blocksize = atoi(opt);
		  if (transfer->blocksize < 1)
		    transfer->blocksize = 1;
		  if (transfer->blocksize > (unsigned)daemon->packet_buff_sz - 4)
		    transfer->blocksize = (unsigned)daemon->packet_buff_sz - 4;
		  /* 32 bytes for IP, UDP and TFTP headers */
		  if (mtu != 0 && transfer->blocksize > (unsigned)mtu - 32)
		    transfer->blocksize = (unsigned)mtu - 32;
		  transfer->opt_blocksize = 1;
		  transfer->block = 0;
		}
	    }
	  else if (strcasecmp(opt, "tsize") == 0 && next(&p, end) && !transfer->netascii)
	    {
	      transfer->opt_transize = 1;
	      transfer->block = 0;
	    }
	}

      /* cope with backslashes from windows boxen. */
      while ((p = strchr(filename, '\\')))
	*p = '/';

      strcpy(daemon->namebuff, "/");
      if (prefix)
	{
	  if (prefix[0] == '/')
	    daemon->namebuff[0] = 0;
	  strncat(daemon->namebuff, prefix, (MAXDNAME-1) - strlen(daemon->namebuff));
	  if (prefix[strlen(prefix)-1] != '/')
	    strncat(daemon->namebuff, "/", (MAXDNAME-1) - strlen(daemon->namebuff));

	  if (!special && option_bool(OPT_TFTP_APREF))
	    {
	      size_t oldlen = strlen(daemon->namebuff);
	      struct stat statbuf;
	      
	      strncat(daemon->namebuff, pretty_addr, (MAXDNAME-1) - strlen(daemon->namebuff));
	      strncat(daemon->namebuff, "/", (MAXDNAME-1) - strlen(daemon->namebuff));
	      
	      /* remove unique-directory if it doesn't exist */
	      if (stat(daemon->namebuff, &statbuf) == -1 || !S_ISDIR(statbuf.st_mode))
		daemon->namebuff[oldlen] = 0;
	    }
		
	  /* Absolute pathnames OK if they match prefix */
	  if (filename[0] == '/')
	    {
	      if (strstr(filename, daemon->namebuff) == filename)
		daemon->namebuff[0] = 0;
	      else
		filename++;
	    }
	}
      else if (filename[0] == '/')
	daemon->namebuff[0] = 0;
      strncat(daemon->namebuff, filename, (MAXDNAME-1) - strlen(daemon->namebuff));

      /* check permissions and open file */
      if ((transfer->file = check_tftp_fileperm(&len, prefix, special)))
	{
	  if ((len = get_block(packet, transfer)) == -1)
	    len = tftp_err_oops(packet, daemon->namebuff);
	  else
	    is_err = 0;
	}
    }
  
  while (sendto(transfer->sockfd, packet, len, 0, 
		(struct sockaddr *)&peer, sizeof(peer)) == -1 && errno == EINTR);
  
  if (is_err)
    free_transfer(transfer);
  else
    {
      transfer->next = daemon->tftp_trans;
      daemon->tftp_trans = transfer;
    }
}