svc_udp.c

Axis 221 camera embedded programing interface

/* @(#)svc_udp.c	2.2 88/07/29 4.0 RPCSRC */
/*
 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
 * unrestricted use provided that this legend is included on all tape
 * media and as a part of the software program in whole or part.  Users
 * may copy or modify Sun RPC without charge, but are not authorized
 * to license or distribute it to anyone else except as part of a product or
 * program developed by the user.
 *
 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 *
 * Sun RPC is provided with no support and without any obligation on the
 * part of Sun Microsystems, Inc. to assist in its use, correction,
 * modification or enhancement.
 *
 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
 * OR ANY PART THEREOF.
 *
 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 * or profits or other special, indirect and consequential damages, even if
 * Sun has been advised of the possibility of such damages.
 *
 * Sun Microsystems, Inc.
 * 2550 Garcia Avenue
 * Mountain View, California  94043
 */
#if 0
static char sccsid[] = "@(#)svc_udp.c 1.24 87/08/11 Copyr 1984 Sun Micro";
#endif

/*
 * svc_udp.c,
 * Server side for UDP/IP based RPC.  (Does some caching in the hopes of
 * achieving execute-at-most-once semantics.)
 *
 * Copyright (C) 1984, Sun Microsystems, Inc.
 */

#define __FORCE_GLIBC
#define _GNU_SOURCE
#include <features.h>

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <rpc/rpc.h>
#include <sys/socket.h>
#include <errno.h>

#ifdef IP_PKTINFO
#include <sys/uio.h>
#endif

#ifdef USE_IN_LIBIO
# include <wchar.h>
# include <libio/iolibio.h>
# define fputs(s, f) _IO_fputs (s, f)
#endif

#define rpc_buffer(xprt) ((xprt)->xp_p1)
#ifndef MAX
#define MAX(a, b)     ((a > b) ? a : b)
#endif

static bool_t svcudp_recv (SVCXPRT *, struct rpc_msg *);
static bool_t svcudp_reply (SVCXPRT *, struct rpc_msg *);
static enum xprt_stat svcudp_stat (SVCXPRT *);
static bool_t svcudp_getargs (SVCXPRT *, xdrproc_t, caddr_t);
static bool_t svcudp_freeargs (SVCXPRT *, xdrproc_t, caddr_t);
static void svcudp_destroy (SVCXPRT *);

static const struct xp_ops svcudp_op =
{
  svcudp_recv,
  svcudp_stat,
  svcudp_getargs,
  svcudp_reply,
  svcudp_freeargs,
  svcudp_destroy
};

static int cache_get (SVCXPRT *, struct rpc_msg *, char **replyp,
		      u_long *replylenp);
static void cache_set (SVCXPRT *xprt, u_long replylen);

/*
 * kept in xprt->xp_p2
 */
struct svcudp_data
  {
    u_int su_iosz;		/* byte size of send.recv buffer */
    u_long su_xid;		/* transaction id */
    XDR su_xdrs;		/* XDR handle */
    char su_verfbody[MAX_AUTH_BYTES];	/* verifier body */
    char *su_cache;		/* cached data, NULL if no cache */
  };
#define	su_data(xprt)	((struct svcudp_data *)(xprt->xp_p2))

/*
 * Usage:
 *      xprt = svcudp_create(sock);
 *
 * If sock<0 then a socket is created, else sock is used.
 * If the socket, sock is not bound to a port then svcudp_create
 * binds it to an arbitrary port.  In any (successful) case,
 * xprt->xp_sock is the registered socket number and xprt->xp_port is the
 * associated port number.
 * Once *xprt is initialized, it is registered as a transporter;
 * see (svc.h, xprt_register).
 * The routines returns NULL if a problem occurred.
 */
SVCXPRT *
svcudp_bufcreate (sock, sendsz, recvsz)
     int sock;
     u_int sendsz, recvsz;
{
  bool_t madesock = FALSE;
  SVCXPRT *xprt;
  struct svcudp_data *su;
  struct sockaddr_in addr;
  socklen_t len = sizeof (struct sockaddr_in);
  int pad;
  void *buf;

  if (sock == RPC_ANYSOCK)
    {
      if ((sock = socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
	{
	  perror (_("svcudp_create: socket creation problem"));
	  return (SVCXPRT *) NULL;
	}
      madesock = TRUE;
    }
  memset ((char *) &addr, 0, sizeof (addr));
  addr.sin_family = AF_INET;
  if (bindresvport (sock, &addr))
    {
      addr.sin_port = 0;
      (void) bind (sock, (struct sockaddr *) &addr, len);
    }
  if (getsockname (sock, (struct sockaddr *) &addr, &len) != 0)
    {
      perror (_("svcudp_create - cannot getsockname"));
      if (madesock)
	(void) close (sock);
      return (SVCXPRT *) NULL;
    }
  xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT));
  su = (struct svcudp_data *) mem_alloc (sizeof (*su));
  buf = mem_alloc (((MAX (sendsz, recvsz) + 3) / 4) * 4);
  if (xprt == NULL || su == NULL || buf == NULL)
    {
#ifdef USE_IN_LIBIO
      if (_IO_fwide (stderr, 0) > 0)
	(void) __fwprintf (stderr, L"%s", _("svcudp_create: out of memory\n"));
      else
#endif
	(void) fputs (_("svcudp_create: out of memory\n"), stderr);
      mem_free (xprt, sizeof (SVCXPRT));
      mem_free (su, sizeof (*su));
      mem_free (buf, ((MAX (sendsz, recvsz) + 3) / 4) * 4);
      return NULL;
    }
  su->su_iosz = ((MAX (sendsz, recvsz) + 3) / 4) * 4;
  rpc_buffer (xprt) = buf;
  xdrmem_create (&(su->su_xdrs), rpc_buffer (xprt), su->su_iosz, XDR_DECODE);
  su->su_cache = NULL;
  xprt->xp_p2 = (caddr_t) su;
  xprt->xp_verf.oa_base = su->su_verfbody;
  xprt->xp_ops = &svcudp_op;
  xprt->xp_port = ntohs (addr.sin_port);
  xprt->xp_sock = sock;

#ifdef IP_PKTINFO
  if ((sizeof (struct iovec) + sizeof (struct msghdr)
       + sizeof(struct cmsghdr) + sizeof (struct in_pktinfo))
      > sizeof (xprt->xp_pad))
    {
# ifdef USE_IN_LIBIO
      if (_IO_fwide (stderr, 0) > 0)
	(void) __fwprintf (stderr, L"%s",
			   _("svcudp_create: xp_pad is too small for IP_PKTINFO\n"));
      else
# endif
	(void) fputs (_("svcudp_create: xp_pad is too small for IP_PKTINFO\n"),
		      stderr);
      return NULL;
    }
  pad = 1;
  if (setsockopt (sock, SOL_IP, IP_PKTINFO, (void *) &pad,
		  sizeof (pad)) == 0)
    /* Set the padding to all 1s. */
    pad = 0xff;
  else
#endif
    /* Clear the padding. */
    pad = 0;
  memset (&xprt->xp_pad [0], pad, sizeof (xprt->xp_pad));

  xprt_register (xprt);
  return xprt;
}

SVCXPRT *
svcudp_create (sock)
     int sock;
{

  return svcudp_bufcreate (sock, UDPMSGSIZE, UDPMSGSIZE);
}

static enum xprt_stat
svcudp_stat (xprt)
     SVCXPRT *xprt;
{

  return XPRT_IDLE;
}

static bool_t
svcudp_recv (xprt, msg)
     SVCXPRT *xprt;
     struct rpc_msg *msg;
{
  struct svcudp_data *su = su_data (xprt);
  XDR *xdrs = &(su->su_xdrs);
  int rlen;
  char *reply;
  u_long replylen;
  socklen_t len;

  /* It is very tricky when you have IP aliases. We want to make sure
     that we are sending the packet from the IP address where the
     incoming packet is addressed to. H.J. */
#ifdef IP_PKTINFO
  struct iovec *iovp;
  struct msghdr *mesgp;
#endif

again:
  /* FIXME -- should xp_addrlen be a size_t?  */
  len = (socklen_t) sizeof(struct sockaddr_in);
#ifdef IP_PKTINFO
  iovp = (struct iovec *) &xprt->xp_pad [0];
  mesgp = (struct msghdr *) &xprt->xp_pad [sizeof (struct iovec)];
  if (mesgp->msg_iovlen)
    {
      iovp->iov_base = rpc_buffer (xprt);
      iovp->iov_len = su->su_iosz;
      mesgp->msg_iov = iovp;
      mesgp->msg_iovlen = 1;
      mesgp->msg_name = &(xprt->xp_raddr);
      mesgp->msg_namelen = len;
      mesgp->msg_control = &xprt->xp_pad [sizeof (struct iovec)
					  + sizeof (struct msghdr)];
      mesgp->msg_controllen = sizeof(xprt->xp_pad)
			      - sizeof (struct iovec) - sizeof (struct msghdr);
      rlen = recvmsg (xprt->xp_sock, mesgp, 0);
      if (rlen >= 0)
	len = mesgp->msg_namelen;
    }
  else
#endif
    rlen = recvfrom (xprt->xp_sock, rpc_buffer (xprt),
		     (int) su->su_iosz, 0,
		     (struct sockaddr *) &(xprt->xp_raddr), &len);
  xprt->xp_addrlen = len;
  if (rlen == -1 && errno == EINTR)
    goto again;
  if (rlen < 16)		/* < 4 32-bit ints? */
    return FALSE;
  xdrs->x_op = XDR_DECODE;
  XDR_SETPOS (xdrs, 0);
  if (!xdr_callmsg (xdrs, msg))
    return FALSE;
  su->su_xid = msg->rm_xid;
  if (su->su_cache != NULL)
    {
      if (cache_get (xprt, msg, &reply, &replylen))
	{
#ifdef IP_PKTINFO
	  if (mesgp->msg_iovlen)
	    {
	      iovp->iov_base = reply;
	      iovp->iov_len = replylen;
	      (void) sendmsg (xprt->xp_sock, mesgp, 0);
	    }
	  else
#endif
	    (void) sendto (xprt->xp_sock, reply, (int) replylen, 0,
			   (struct sockaddr *) &xprt->xp_raddr, len);
	  return TRUE;
	}
    }
  return TRUE;
}

static bool_t
svcudp_reply (xprt, msg)
     SVCXPRT *xprt;
     struct rpc_msg *msg;
{
  struct svcudp_data *su = su_data (xprt);
  XDR *xdrs = &(su->su_xdrs);