bootp_subr.c

RTEMS (Real-Time Executive for Multiprocessor Systems) is a free open source real-time operating sys

/*	$Id: bootp_subr.c,v 1.11.2.2 2004/09/17 16:38:05 joel Exp $	*/

/*
 * Copyright (c) 1995 Gordon Ross, Adam Glass
 * Copyright (c) 1992 Regents of the University of California.
 * All rights reserved.
 *
 * This software was developed by the Computer Systems Engineering group
 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
 * contributed to Berkeley.
 *
 * 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, Lawrence Berkeley Laboratory 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.
 *
 * based on:
 *      nfs/krpc_subr.c
 *	$NetBSD: krpc_subr.c,v 1.10 1995/08/08 20:43:43 gwr Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/sockio.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/mbuf.h>
#include <sys/reboot.h>
#include <sys/socket.h>
#include <sys/socketvar.h>

#include <net/if.h>
#include <net/route.h>

#include <netinet/in.h>
#include <net/if_types.h>
#include <net/if_dl.h>
#include <netinet/if_ether.h>

#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs.h>
#include <nfs/nfsdiskless.h>
#include <nfs/krpc.h>
#include <nfs/xdr_subs.h>

#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <rtems/mkrootfs.h>
#include <rtems/rtems_bsdnet.h>

#define BOOTP_MIN_LEN		300	/* Minimum size of bootp udp packet */

/*
 * What is the longest we will wait before re-sending a request?
 * Note this is also the frequency of "RPC timeout" messages.
 * The re-send loop count sup linearly to this maximum, so the
 * first complaint will happen after (1+2+3+4+5)=15 seconds.
 */
#define	MAX_RESEND_DELAY 5	/* seconds */

/* Definitions from RFC951 */
struct bootp_packet {
  u_int8_t op;
  u_int8_t htype;
  u_int8_t hlen;
  u_int8_t hops;
  u_int32_t xid;
  u_int16_t secs;
  u_int16_t flags;
  struct in_addr ciaddr;
  struct in_addr yiaddr;
  struct in_addr siaddr;
  struct in_addr giaddr;
  unsigned char chaddr[16];
  char sname[64];
  char file[128];
  unsigned char vend[256];
};

#define IPPORT_BOOTPC 68
#define IPPORT_BOOTPS 67

extern int nfs_diskless_valid;
extern struct nfsv3_diskless nfsv3_diskless;

/* mountd RPC */
#if !defined(__rtems__)
static int md_mount __P((struct sockaddr_in *mdsin, char *path,
	u_char *fhp, int *fhsizep, struct nfs_args *args,struct proc *procp));
static int md_lookup_swap __P((struct sockaddr_in *mdsin,char *path,
			       u_char *fhp, int *fhsizep, 
			       struct nfs_args *args,
			       struct proc *procp));
static int setfs __P((struct sockaddr_in *addr, char *path, char *p));
static int getdec __P((char **ptr));
#endif
#if !defined(__rtems__)
static char *substr __P((char *a,char *b));
static void mountopts __P((struct nfs_args *args, char *p)); 
static int xdr_opaque_decode __P((struct mbuf **ptr,u_char *buf,
				  int len));
static int xdr_int_decode __P((struct mbuf **ptr,int *iptr));
#endif
static void printip __P((char *prefix,struct in_addr addr));

#ifdef BOOTP_DEBUG
void bootpboot_p_sa(struct sockaddr *sa,struct sockaddr *ma);
void bootpboot_p_ma(struct sockaddr *ma);
void bootpboot_p_rtentry(struct rtentry *rt);
void bootpboot_p_tree(struct radix_node *rn);
void bootpboot_p_rtlist(void);
void bootpboot_p_iflist(void);
#endif

int  bootpc_call(struct bootp_packet *call,
		 struct bootp_packet *reply,
		 struct proc *procp);

int bootpc_fakeup_interface(struct ifreq *ireq,struct socket *so,
			struct proc *procp);

int 
bootpc_adjust_interface(struct ifreq *ireq,struct socket *so,
			struct sockaddr_in *myaddr,
			struct sockaddr_in *netmask,
			struct sockaddr_in *gw,
			struct proc *procp);

void bootpc_init(int update_files);

#ifdef BOOTP_DEBUG
void bootpboot_p_sa(sa,ma)
     struct sockaddr *sa;
     struct sockaddr *ma;
{
  if (!sa) {
    printf("(sockaddr *) <null>");
    return;
  }
  switch (sa->sa_family) {
  case AF_INET:
    {
      struct sockaddr_in *sin = (struct sockaddr_in *) sa;
      printf("inet %x",ntohl(sin->sin_addr.s_addr));
      if (ma) {
	struct sockaddr_in *sin = (struct sockaddr_in *) ma;
	printf(" mask %x",ntohl(sin->sin_addr.s_addr));
      }
    }
  break;
  case AF_LINK:
    {
      struct sockaddr_dl *sli = (struct sockaddr_dl *) sa;
      int i;
      printf("link %.*s ",sli->sdl_nlen,sli->sdl_data);
      for (i=0;i<sli->sdl_alen;i++) {
	if (i>0)
	  printf(":");
	printf("%x",(unsigned char) sli->sdl_data[i+sli->sdl_nlen]);
      }
    }
  break;
  default:
    printf("af%d",sa->sa_family);
  }
}

void bootpboot_p_ma(ma)
     struct sockaddr *ma;
{
  if (!ma) {
    printf("<null>");
    return;
  }
  printf("%x",*(int*)ma);
}

void bootpboot_p_rtentry(rt)
     struct rtentry *rt;
{
  bootpboot_p_sa(rt_key(rt),rt_mask(rt));
  printf(" ");
  bootpboot_p_ma(rt->rt_genmask);
  printf(" ");
  bootpboot_p_sa(rt->rt_gateway,NULL);
  printf(" ");
  printf("flags %x",(unsigned short) rt->rt_flags);
  printf(" %d",rt->rt_rmx.rmx_expire);
  printf(" %s%d\n",rt->rt_ifp->if_name,rt->rt_ifp->if_unit);
}
void  bootpboot_p_tree(rn)
     struct radix_node *rn;
{
  while (rn) {
    if (rn->rn_b < 0) {
      if (rn->rn_flags & RNF_ROOT) {
      } else {
	bootpboot_p_rtentry((struct rtentry *) rn);
      }
      rn = rn->rn_dupedkey;
    } else {
      bootpboot_p_tree(rn->rn_l);
      bootpboot_p_tree(rn->rn_r);
      return;
    }
    
  }
}

void bootpboot_p_rtlist(void)
{
  printf("Routing table:\n");
  bootpboot_p_tree(rt_tables[AF_INET]->rnh_treetop);
}

void bootpboot_p_iflist(void)
{
  struct ifnet *ifp;
  struct ifaddr *ifa;
  printf("Interface list:\n");
  for (ifp = TAILQ_FIRST(&ifnet); ifp != 0; ifp = TAILQ_NEXT(ifp,if_link))
    {
      for (ifa = TAILQ_FIRST(&ifp->if_addrhead) ;ifa; 
	   ifa=TAILQ_NEXT(ifa,ifa_link))
	if (ifa->ifa_addr->sa_family == AF_INET ) {
	  printf("%s%d flags %x, addr %x, bcast %x, net %x\n",
		 ifp->if_name,ifp->if_unit,
		 (unsigned short) ifp->if_flags,
		 ntohl(((struct sockaddr_in *) ifa->ifa_addr)->sin_addr.s_addr),
		 ntohl(((struct sockaddr_in *) ifa->ifa_dstaddr)->sin_addr.s_addr),
		 ntohl(((struct sockaddr_in *) ifa->ifa_netmask)->sin_addr.s_addr)
		 );
	}
    }
}
#endif

/*
 * - determine space needed to store src string
 * - allocate or reallocate dst, so that string fits in
 * - copy string from src to dest
 */
void *bootp_strdup_realloc(char *dst,const char *src)
{
  size_t len;
  void *realloc(void * __r, size_t __size);

  if (dst == NULL) {
    /* first allocation, simply use strdup */
	if (src)
    	dst = strdup(src);
  }
  else {
    /* already allocated, so use realloc/strcpy */
    len = src ? strlen(src) + 1 : 0;  
	/* src == NULL tells us to effectively free dst */
    dst = realloc(dst,len);
    if (dst != NULL) {
      strcpy(dst,src);
    }
  }
  return dst;
}

int
bootpc_call(call,reply,procp)
     struct bootp_packet *call;
     struct bootp_packet *reply;	/* output */
     struct proc *procp;
{
	struct socket *so;
	struct sockaddr_in *sin;
	struct mbuf *m, *nam;
	struct uio auio;
	struct iovec aio;
	int error, rcvflg, timo, secs, len;

	/* Free at end if not null. */
	nam = NULL;

	/*
	 * Create socket and set its recieve timeout.
	 */
	if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0,procp)))
		goto out;

	m = m_get(M_WAIT, MT_SOOPTS);
	if (m == NULL) {
		error = ENOBUFS;
		goto out;
	} else {
		struct timeval *tv;
		tv = mtod(m, struct timeval *);
		m->m_len = sizeof(*tv);
		tv->tv_sec = 1;
		tv->tv_usec = 0;
		if ((error = sosetopt(so, SOL_SOCKET, SO_RCVTIMEO, m)))
			goto out;
	}

	/*
	 * Enable broadcast.
	 */
	{
		int *on;
		m = m_get(M_WAIT, MT_SOOPTS);
		if (m == NULL) {
			error = ENOBUFS;
			goto out;
		}
		on = mtod(m, int *);
		m->m_len = sizeof(*on);
		*on = 1;
		if ((error = sosetopt(so, SOL_SOCKET, SO_BROADCAST, m)))
			goto out;
	}

	/*
	 * Bind the local endpoint to a bootp client port.
	 */
	m = m_getclr(M_WAIT, MT_SONAME);
	sin = mtod(m, struct sockaddr_in *);
	sin->sin_len = m->m_len = sizeof(*sin);
	sin->sin_family = AF_INET;
	sin->sin_addr.s_addr = INADDR_ANY;
	sin->sin_port = htons(IPPORT_BOOTPC);
	error = sobind(so, m);
	m_freem(m);
	if (error) {
		printf("bind failed\n");
		goto out;
	}

	/*
	 * Setup socket address for the server.
	 */
	nam = m_get(M_WAIT, MT_SONAME);
	if (nam == NULL) {
		error = ENOBUFS;
		goto out;
	}
	sin = mtod(nam, struct sockaddr_in *);
	sin-> sin_len = sizeof(*sin);
	sin-> sin_family = AF_INET;
	sin->sin_addr.s_addr = INADDR_BROADCAST;
	sin->sin_port = htons(IPPORT_BOOTPS);

	nam->m_len = sizeof(*sin);

	/*
	 * Send it, repeatedly, until a reply is received,
	 * but delay each re-send by an increasing amount.
	 * If the delay hits the maximum, start complaining.
	 */
	timo = 0;
	for (;;) {
		/* Send BOOTP request (or re-send). */
		
		aio.iov_base = (caddr_t) call;
		aio.iov_len = sizeof(*call);
		
		auio.uio_iov = &aio;
		auio.uio_iovcnt = 1;
		auio.uio_segflg = UIO_SYSSPACE;
		auio.uio_rw = UIO_WRITE;
		auio.uio_offset = 0;
		auio.uio_resid = sizeof(*call);
		auio.uio_procp = procp;

		error = sosend(so, nam, &auio, NULL, NULL, 0);
		if (error) {
			printf("bootpc_call: sosend: %d\n", error);
			goto out;
		}

		/* Determine new timeout. */
		if (timo < MAX_RESEND_DELAY)
			timo++;
		else
			printf("BOOTP timeout for server 0x%x\n",
			       (int)ntohl(sin->sin_addr.s_addr));

		/*
		 * Wait for up to timo seconds for a reply.
		 * The socket receive timeout was set to 1 second.
		 */
		secs = timo;
		while (secs > 0) {
			aio.iov_base = (caddr_t) reply;
			aio.iov_len = sizeof(*reply);

			auio.uio_iov = &aio;
			auio.uio_iovcnt = 1;
			auio.uio_segflg = UIO_SYSSPACE;
			auio.uio_rw = UIO_READ;
			auio.uio_offset = 0;
			auio.uio_resid = sizeof(*reply);
			auio.uio_procp = procp;
			
			rcvflg = 0;
			error = soreceive(so, NULL, &auio, NULL, NULL, &rcvflg);
			if (error == EWOULDBLOCK) {
				secs--;
				call->secs=htons(ntohs(call->secs)+1);
				continue;
			}
			if (error)
				goto out;
			len = sizeof(*reply) - auio.uio_resid;

			/* Do we have the required number of bytes ? */
			if (len < BOOTP_MIN_LEN)
				continue;

			/* Is it the right reply? */
			if (reply->op != 2)
			  continue;

			if (reply->xid != call->xid)
				continue;

			if (reply->hlen != call->hlen)
			  continue;

			if (bcmp(reply->chaddr,call->chaddr,call->hlen))
			  continue;

			goto gotreply;	/* break two levels */

		} /* while secs */
	} /* forever send/receive */

	error = ETIMEDOUT;
	goto out;

 gotreply:
 out:
	if (nam) m_freem(nam);
	soclose(so);
	return error;
}

int 
bootpc_fakeup_interface(struct ifreq *ireq,struct socket *so,
			struct proc *procp)
{
  struct sockaddr_in *sin;
  int error;
  struct sockaddr_in dst;
  struct sockaddr_in gw;
  struct sockaddr_in mask;

  /*
   * Bring up the interface.
   *
   * Get the old interface flags and or IFF_UP into them; if
   * IFF_UP set blindly, interface selection can be clobbered.
   */
  error = ifioctl(so, SIOCGIFFLAGS, (caddr_t)ireq, procp);
  if (error)
    panic("bootpc_fakeup_interface: GIFFLAGS, error=%d", error);
  ireq->ifr_flags |= IFF_UP;
  error = ifioctl(so, SIOCSIFFLAGS, (caddr_t)ireq, procp);
  if (error)
    panic("bootpc_fakeup_interface: SIFFLAGS, error=%d", error);

  /*
   * Do enough of ifconfig(8) so that the chosen interface
   * can talk to the servers.  (just set the address)
   */
  
  /* addr is 0.0.0.0 */
  
  sin = (struct sockaddr_in *)&ireq->ifr_addr;
  bzero((caddr_t)sin, sizeof(*sin));
  sin->sin_len = sizeof(*sin);
  sin->sin_family = AF_INET;
  sin->sin_addr.s_addr = INADDR_ANY;
  error = ifioctl(so, SIOCSIFADDR, (caddr_t)ireq, procp);
  if (error)
    panic("bootpc_fakeup_interface: set if addr, error=%d", error);
  
  /* netmask is 0.0.0.0 */
  
  sin = (struct sockaddr_in *)&ireq->ifr_addr;
  bzero((caddr_t)sin, sizeof(*sin));
  sin->sin_len = sizeof(*sin);
  sin->sin_family = AF_INET;
  sin->sin_addr.s_addr = INADDR_ANY;
  error = ifioctl(so, SIOCSIFNETMASK, (caddr_t)ireq, procp);
  if (error)
    panic("bootpc_fakeup_interface: set if net addr, error=%d", error);
  
  /* Broadcast is 255.255.255.255 */
  
  sin = (struct sockaddr_in *)&ireq->ifr_addr;
  bzero((caddr_t)sin, sizeof(*sin));
  sin->sin_len = sizeof(*sin);
  sin->sin_family = AF_INET;
  sin->sin_addr.s_addr = INADDR_BROADCAST;
  error = ifioctl(so, SIOCSIFBRDADDR, (caddr_t)ireq, procp);
  if (error)
    panic("bootpc_fakeup_interface: set if broadcast addr, error=%d", error);
  
  /* Add default route to 0.0.0.0 so we can send data */
  
  bzero((caddr_t) &dst, sizeof(dst));
  dst.sin_len=sizeof(dst);
  dst.sin_family=AF_INET;
  dst.sin_addr.s_addr = htonl(0);
  
  bzero((caddr_t) &gw, sizeof(gw));
  gw.sin_len=sizeof(gw);
  gw.sin_family=AF_INET;
  gw.sin_addr.s_addr = htonl(0x0);
  
  bzero((caddr_t) &mask, sizeof(mask));
  mask.sin_len=sizeof(mask);
  mask.sin_family=AF_INET;
  mask.sin_addr.s_addr = htonl(0);
  
  error = rtrequest(RTM_ADD, 
		    (struct sockaddr *) &dst, 
		    (struct sockaddr *) &gw,
		    (struct sockaddr *) &mask, 
		    RTF_UP | RTF_STATIC
		    , NULL);
  if (error)
    printf("bootpc_fakeup_interface: add default route, error=%d\n", error);
  return error;
}

int 
bootpc_adjust_interface(struct ifreq *ireq,struct socket *so,
			struct sockaddr_in *myaddr,
			struct sockaddr_in *netmask,
			struct sockaddr_in *gw,
			struct proc *procp)
{
  int error;
  struct sockaddr_in oldgw;
  struct sockaddr_in olddst;
  struct sockaddr_in oldmask;
  struct sockaddr_in *sin;

  /* Remove old default route to 0.0.0.0 */
  
  bzero((caddr_t) &olddst, sizeof(olddst));
  olddst.sin_len=sizeof(olddst);
  olddst.sin_family=AF_INET;
  olddst.sin_addr.s_addr = INADDR_ANY;
  
  bzero((caddr_t) &oldgw, sizeof(oldgw));
  oldgw.sin_len=sizeof(oldgw);
  oldgw.sin_family=AF_INET;
  oldgw.sin_addr.s_addr = INADDR_ANY;