[apple/xnu.git] / bsd / netinet / in_bootp.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 *  Copyright (c) 1988-1999 Apple Computer, Inc. All Rights Reserved 
 */

/*
 * bootp.c
 * - be a BOOTP client over a particular interface to retrieve
 *   the IP address, netmask, and router
 */

/* 
 * Modification History
 *
 * February 19, 1999	Dieter Siegmund	(dieter@apple.com)
 * - completely rewritten
 */

#include <sys/param.h>
#include <sys/types.h>
#include <mach/boolean.h>
#include <sys/kernel.h>
#include <sys/errno.h>
#include <sys/file.h>
#include <sys/uio.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/mbuf.h>
#include <sys/vnode.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/if_ether.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/ip_icmp.h>
#include <netinet/bootp.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <netinet/dhcp_options.h>

#ifdef	BOOTP_DEBUG
#define	dprintf(x) printf x;
#else	/* !BOOTP_DEBUG */
#define	dprintf(x)
#endif	/* BOOTP_DEBUG */

/* ip address formatting macros */
#define IP_FORMAT	"%d.%d.%d.%d"
#define IP_CH(ip)	((u_char *)ip)
#define IP_LIST(ip)	IP_CH(ip)[0],IP_CH(ip)[1],IP_CH(ip)[2],IP_CH(ip)[3]

static __inline__ struct sockaddr_in
blank_sin()
{
    struct sockaddr_in	blank = { sizeof(struct sockaddr_in), AF_INET };
    return (blank);
}

static __inline__ void
print_reply(struct bootp *bp, int bp_len)
{
	int i, j, len;

	printf("bp_op = ");
	if (bp->bp_op == BOOTREQUEST) printf("BOOTREQUEST\n");
	else if (bp->bp_op == BOOTREPLY) printf("BOOTREPLY\n");
	else
	{
		i = bp->bp_op;
		printf("%d\n", i);
	}

	i = bp->bp_htype;
	printf("bp_htype = %d\n", i);

	len = bp->bp_hlen;
	printf("bp_hlen = %d\n", len);

	i = bp->bp_hops;
	printf("bp_hops = %d\n", i);

	printf("bp_xid = %lu\n", bp->bp_xid);

	printf("bp_secs = %u\n", bp->bp_secs);

	printf("bp_ciaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_ciaddr));
	printf("bp_yiaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_yiaddr));
	printf("bp_siaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_siaddr));
	printf("bp_giaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_giaddr));

	printf("bp_chaddr = ");
	for (j = 0; j < len; j++)
	{
		i = bp->bp_chaddr[j];
		printf("%0x", i);
		if (j < (len - 1)) printf(":");
	}
	printf("\n");

	printf("bp_sname = %s\n", bp->bp_sname);
	printf("bp_file = %s\n", bp->bp_file);
}

static __inline__ void
print_reply_short(struct bootp *bp, int bp_len)
{
	printf("bp_yiaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_yiaddr));
	printf("bp_sname = %s\n", bp->bp_sname);
}


static __inline__ long
random_range(long bottom, long top)
{
    long number = top - bottom + 1;
    long range_size = LONG_MAX / number;
    return (((long)random()) / range_size + bottom);
}

/*
 * Function: make_bootp_request
 * Purpose:
 *   Create a "blank" bootp packet.
 */
static void
make_bootp_request(struct bootp_packet * pkt, 
		   u_char * hwaddr, u_char hwtype, u_char hwlen)
{
    char		rfc_magic[4] = RFC_OPTIONS_MAGIC;

    bzero(pkt, sizeof (*pkt));
    pkt->bp_ip.ip_v = IPVERSION;
    pkt->bp_ip.ip_hl = sizeof (struct ip) >> 2;
#ifdef RANDOM_IP_ID
    pkt->bp_ip.ip_id = ip_randomid();
#else
    pkt->bp_ip.ip_id = htons(ip_id++);
#endif
    pkt->bp_ip.ip_ttl = MAXTTL;
    pkt->bp_ip.ip_p = IPPROTO_UDP;
    pkt->bp_ip.ip_src.s_addr = 0;
    pkt->bp_ip.ip_dst.s_addr = htonl(INADDR_BROADCAST);
    pkt->bp_udp.uh_sport = htons(IPPORT_BOOTPC);
    pkt->bp_udp.uh_dport = htons(IPPORT_BOOTPS);
    pkt->bp_udp.uh_sum = 0;
    pkt->bp_bootp.bp_op = BOOTREQUEST;
    pkt->bp_bootp.bp_htype = hwtype;
    pkt->bp_bootp.bp_hlen = hwlen;
    pkt->bp_bootp.bp_ciaddr.s_addr = 0;
    bcopy(hwaddr, pkt->bp_bootp.bp_chaddr, hwlen);
    bcopy(rfc_magic, pkt->bp_bootp.bp_vend, sizeof(rfc_magic));
    pkt->bp_bootp.bp_vend[4] = dhcptag_end_e;
    pkt->bp_udp.uh_ulen = htons(sizeof(pkt->bp_udp) + sizeof(pkt->bp_bootp));
    pkt->bp_ip.ip_len = htons(sizeof(struct ip) + ntohs(pkt->bp_udp.uh_ulen));
    pkt->bp_ip.ip_sum = 0;
    return;
}

/*
 * Function: ip_pkt_to_mbuf
 * Purpose:
 *   Put the given IP packet into an mbuf, calculate the
 *   IP checksum.
 */
struct mbuf *
ip_pkt_to_mbuf(caddr_t pkt, int pktsize)
{
    struct ip *		ip;
    struct mbuf	*	m;
    
    m = (struct mbuf *)m_devget(pkt, pktsize, 0, 0, 0);
    if (m == 0) {
	printf("bootp: ip_pkt_to_mbuf: m_devget failed\n");
	return 0;
    }
    m->m_flags |= M_BCAST;
    /* Compute the checksum */
    ip = mtod(m, struct ip *);
    ip->ip_sum = 0;
    ip->ip_sum = in_cksum(m, sizeof (struct ip));
    return (m);
}

static __inline__ u_char *
link_address(struct sockaddr_dl * dl_p)
{
    return (dl_p->sdl_data + dl_p->sdl_nlen);
}

static __inline__ void
link_print(struct sockaddr_dl * dl_p)
{
    int i;

#if 0
    printf("len %d index %d family %d type 0x%x nlen %d alen %d"
	   " slen %d addr ", dl_p->sdl_len, 
	   dl_p->sdl_index,  dl_p->sdl_family, dl_p->sdl_type,
	   dl_p->sdl_nlen, dl_p->sdl_alen, dl_p->sdl_slen);
#endif
    for (i = 0; i < dl_p->sdl_alen; i++) 
	printf("%s%x", i ? ":" : "", 
	       (link_address(dl_p))[i]);
    printf("\n");
    return;
}

static struct sockaddr_dl *
link_from_ifnet(struct ifnet * ifp)
{
    struct ifaddr * addr;

/*    for (addr = ifp->if_addrlist; addr; addr = addr->ifa_next) */

    TAILQ_FOREACH(addr, &ifp->if_addrhead, ifa_link) {
	if (addr->ifa_addr->sa_family == AF_LINK) {
	    struct sockaddr_dl * dl_p = (struct sockaddr_dl *)(addr->ifa_addr);
	    
	    return (dl_p);
	}
    }
    return (NULL);
}

/*
 * Function: send_bootp_request
 * Purpose:
 *     Send the request by calling the interface's output routine
 *     bypassing routing code.
 */
static int
send_bootp_request(struct ifnet * ifp, struct socket * so,
		   struct bootp_packet * pkt)
{
    struct mbuf	*	m;
    struct sockaddr_in	sin;
    
    /* Address to send to */
    sin = blank_sin();
    sin.sin_port = htons(IPPORT_BOOTPS);
    sin.sin_addr.s_addr = INADDR_BROADCAST;
    
    m = ip_pkt_to_mbuf((caddr_t)pkt, sizeof(*pkt));
    return (dlil_output(ifptodlt(ifp, PF_INET), m, 0, (struct sockaddr *)&sin, 0));
}

/*
 * Function: receive_packet
 * Purpose:
 *   Return a received packet or an error if none available.
 */
int
receive_packet(struct socket * so, caddr_t pp, int psize, int * actual_size)
{
    struct iovec	aiov;
    struct uio		auio;
    int			rcvflg;
    int			error;

    aiov.iov_base = pp;
    aiov.iov_len = psize;
    auio.uio_iov = &aiov;
    auio.uio_iovcnt = 1;
    auio.uio_segflg = UIO_SYSSPACE;
    auio.uio_offset = 0;
    auio.uio_resid = psize;
    auio.uio_rw = UIO_READ;
    rcvflg = MSG_WAITALL;
    
    error = soreceive(so, (struct sockaddr **) 0, &auio, 0, 0, &rcvflg);
    *actual_size = psize - auio.uio_resid;
    return (error);
}

/*
 * Function: bootp_timeout
 * Purpose:
 *   Wakeup the process waiting for something on a socket.
 */
static void
bootp_timeout(void * arg)
{
    struct socket * * socketflag = (struct socket * *)arg;
    struct socket * so = *socketflag;
    boolean_t 	funnel_state;
    
    dprintf(("bootp: timeout\n"));

    funnel_state = thread_funnel_set(network_flock,TRUE);
    *socketflag = NULL;
    sowakeup(so, &so->so_rcv);
    (void) thread_funnel_set(network_flock, FALSE);
    return;
}

/*
 * Function: rate_packet
 * Purpose:
 *   Return an integer point rating value for the given bootp packet.
 *   If yiaddr non-zero, the packet gets a rating of 1.
 *   Another point is given if the packet contains the subnet mask,
 *   and another if the router is present.
 */
#define GOOD_RATING	3
static __inline__ int 
rate_packet(struct bootp * pkt, int pkt_size, dhcpol_t * options_p)
{
    int		len;
    int 	rating = 1;

    if (dhcpol_find(options_p, dhcptag_subnet_mask_e, &len, NULL) != NULL) {
	rating++;
    }
    if (dhcpol_find(options_p, dhcptag_router_e, &len, NULL) != NULL) {
	rating++;
    }
    return (rating);
}

#define INITIAL_WAIT_SECS		4
#define MAX_WAIT_SECS			64
#define GATHER_TIME_SECS		2
#define RAND_TICKS			(hz)	/* one second */

/*
 * Function: bootp_loop
 * Purpose:
 *   Do the actual BOOTP protocol.
 *   The algorithm sends out a packet, waits for a response.
 *   We try max_try times, waiting in an exponentially increasing
 *   amount of time.  Once we receive a good response, we start
 *   a new time period called the "gather time", during which we
 *   either find the perfect packet (one that has ip, mask and router)
 *   or we continue to gather responses.  At the end of the gather period,
 *   we use the best response gathered.
 */
static int
bootp_loop(struct socket * so, struct ifnet * ifp, int max_try,
	   struct in_addr * iaddr_p, struct in_addr * netmask_p,
	   struct in_addr * router_p)
{
    struct timeval		current_time;
    struct sockaddr_dl *	dl_p;
    int				error = 0;
    char *			hwaddr;
    int				hwlen;
    char			hwtype = 0;
    struct bootp_packet * 	request = NULL;
    struct bootp *		reply = NULL;
    int				reply_size = DHCP_PACKET_MIN;
    struct timeval		start_time;
    u_long			xid;
    int				retry;
    struct socket *		timeflag;
    int				wait_ticks = INITIAL_WAIT_SECS * hz;

    /* get the hardware address from the interface */
    dl_p = link_from_ifnet(ifp);
    if (dl_p == NULL) {
	printf("bootp: can't get link address\n");
	return (ENXIO);
    }

    printf("bootp: h/w addr ");
    link_print(dl_p);

    hwaddr = link_address(dl_p);
    hwlen = dl_p->sdl_alen;
    switch (dl_p->sdl_type) {
        case IFT_ETHER:
	    hwtype = ARPHRD_ETHER;
	    break;
        default:
	    printf("bootp: hardware type %d not supported\n",
		   dl_p->sdl_type);
	    panic("bootp: hardware type not supported");
	    break;
    }

    /* set transaction id and remember the start time */
    microtime(&start_time);
    current_time = start_time;
    xid = random();
    
    /* make a request/reply packet */
    request = (struct bootp_packet *)kalloc(sizeof(*request));
    make_bootp_request(request, hwaddr, hwtype, hwlen);
    reply = (struct bootp *)kalloc(reply_size);
    iaddr_p->s_addr = 0;
    printf("bootp: sending request");
    for (retry = 0; retry < max_try; retry++) {
	int	 	gather_count = 0;
	int		last_rating = 0;

	/* Send the request */
	printf(".");
	request->bp_bootp.bp_secs = htons((u_short)(current_time.tv_sec 
						    - start_time.tv_sec));
	request->bp_bootp.bp_xid = htonl(xid);
	error = send_bootp_request(ifp, so, request);
	if (error)
	    goto cleanup;

	timeflag = so;
	wait_ticks += random_range(-RAND_TICKS, RAND_TICKS);
	dprintf(("bootp: waiting %d ticks\n", wait_ticks));
	timeout((timeout_fcn_t)bootp_timeout, &timeflag, wait_ticks);

	while (TRUE) {
	    int 	n = 0;

	    error = receive_packet(so, (caddr_t)reply, reply_size, &n);
	    if (error == 0) {
		dprintf(("\nbootp: received packet\n"));
		if (ntohl(reply->bp_xid) == xid
		    && reply->bp_yiaddr.s_addr
		    && bcmp(reply->bp_chaddr, hwaddr, hwlen) == 0) {
		    int 		rating;
		    dhcpol_t		options;

#ifdef	BOOTP_DEBUG
		    print_reply_short(reply, n);
#endif /* BOOTP_DEBUG */
		    (void)dhcpol_parse_packet(&options, (struct dhcp *)reply, 
					      n, NULL);
		    rating = rate_packet(reply, n, &options);
		    if (rating > last_rating) {
			struct in_addr * 	ip;
			int			len;

			*iaddr_p = reply->bp_yiaddr;
			ip = (struct in_addr *)
			    dhcpol_find(&options, 
					dhcptag_subnet_mask_e, &len, NULL);
			if (ip) {
			    *netmask_p = *ip;
			}
			ip = (struct in_addr *)
			    dhcpol_find(&options, dhcptag_router_e, &len, NULL);
			if (ip) {
			    *router_p = *ip;
			}
			printf("%sbootp: got "
			       "response from %s (" IP_FORMAT ")\n",
			       last_rating == 0 ? "\n" : "",
			       reply->bp_sname, 
			       IP_LIST(&reply->bp_siaddr));
		    }
		    dhcpol_free(&options);
		    if (rating >= GOOD_RATING) {
			untimeout((timeout_fcn_t)bootp_timeout, &timeflag);
			goto done;
		    }
		    if (gather_count == 0) {
			untimeout((timeout_fcn_t)bootp_timeout, &timeflag);
			timeflag = so;
			timeout((timeout_fcn_t)bootp_timeout, &timeflag, 
				hz * GATHER_TIME_SECS);
		    }
		    gather_count++;
		}
		else {
		    dprintf(("bootp: packet ignored\n"));
		}
	    }
	    else if ((error != EWOULDBLOCK)) {
		break;
	    }
	    else if (timeflag == NULL) { /* timed out */
		if (gather_count) {
		    dprintf(("bootp: gathering time has expired"));
		    goto done; /* we have a packet */
		}
		break; /* retry */
	    }
	    else
		sbwait(&so->so_rcv);
	}
	if (error && (error != EWOULDBLOCK)) {
	    dprintf(("bootp: failed to receive packets: %d\n", error));
	    untimeout((timeout_fcn_t)bootp_timeout, &timeflag);
	    goto cleanup;
	}
	wait_ticks *= 2;
	if (wait_ticks > (MAX_WAIT_SECS * hz))
	    wait_ticks = MAX_WAIT_SECS * hz;
	xid++;
	microtime(&current_time);
    }
    error = ETIMEDOUT;
    goto cleanup;

 done:
    error = 0;

 cleanup:
    if (request)
	kfree((caddr_t)request, sizeof (*request));
    if (reply)
	kfree((caddr_t)reply, reply_size);
    return (error);
}

/*
 * Routine: bootp
 * Function:
 *	Use the BOOTP protocol to resolve what our IP address should be
 *	on a particular interface.
 */
int bootp(struct ifnet * ifp, struct in_addr * iaddr_p, int max_try,
	  struct in_addr * netmask_p, struct in_addr * router_p,
	  struct proc * procp)
{
    boolean_t			addr_set = FALSE;
    struct ifreq 		ifr;
    int				error;
    struct socket *		so = NULL;

    /* get a socket */
    error = socreate(AF_INET, &so, SOCK_DGRAM, 0);
    if (error) {
	dprintf(("bootp: socreate failed %d\n", error));
	return (error);
    }

    /* assign the all-zeroes address */
    bzero(&ifr, sizeof(ifr));
    sprintf(ifr.ifr_name, "%s%d", ifp->if_name, ifp->if_unit);
    *((struct sockaddr_in *)&ifr.ifr_addr) = blank_sin();
    error = ifioctl(so, SIOCSIFADDR, (caddr_t)&ifr, procp);
    if (error) {
	dprintf(("bootp: SIOCSIFADDR all-zeroes IP failed: %d\n",
		 error));
	goto cleanup;
    }
    dprintf(("bootp: all-zeroes IP address assigned\n"));
    addr_set = TRUE;
    
    { /* bind the socket */
	struct sockaddr_in * sin;

	sin = _MALLOC(sizeof(struct sockaddr_in), M_IFADDR, M_WAIT);
	if (sin == NULL) {
	  	error = ENOMEM;
		goto cleanup;
	}
	sin->sin_len = sizeof(struct sockaddr_in);
	sin->sin_family = AF_INET;
	sin->sin_port = htons(IPPORT_BOOTPC);
	sin->sin_addr.s_addr = INADDR_ANY;
	error = sobind(so, (struct sockaddr *) sin);

	FREE(sin, M_IFADDR);
	if (error) {
	    dprintf(("bootp: sobind failed, %d\n", error));
	    goto cleanup;
	}
	so->so_state |= SS_NBIO;
    }
    /* do the protocol */
    error = bootp_loop(so, ifp, max_try, iaddr_p, netmask_p, router_p);
    
 cleanup:
    if (so) {
	if (addr_set) {
	    (void) ifioctl(so, SIOCDIFADDR, (caddr_t) &ifr, procp);
	}
	soclose(so);
    }
    return (error);
}
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
e5568f75 A	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
1c79356b	11	*
e5568f75 A	12	* This Original Code and all software distributed under the License are
e5568f75 A	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
e5568f75 A	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
1c79356b A	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/*
	23	* Copyright (c) 1988-1999 Apple Computer, Inc. All Rights Reserved
	24	*/
	25
	26	/*
	27	* bootp.c
	28	* - be a BOOTP client over a particular interface to retrieve
	29	* the IP address, netmask, and router
	30	*/
	31
	32	/*
	33	* Modification History
	34	*
	35	* February 19, 1999 Dieter Siegmund (dieter@apple.com)
	36	* - completely rewritten
	37	*/
	38
	39	#include <sys/param.h>
	40	#include <sys/types.h>
	41	#include <mach/boolean.h>
	42	#include <sys/kernel.h>
	43	#include <sys/errno.h>
	44	#include <sys/file.h>
	45	#include <sys/uio.h>
	46	#include <sys/ioctl.h>
	47	#include <sys/time.h>
	48	#include <sys/mbuf.h>
	49	#include <sys/vnode.h>
	50	#include <sys/socket.h>
	51	#include <sys/socketvar.h>
	52	#include <net/if.h>
	53	#include <net/if_dl.h>
	54	#include <net/if_types.h>
	55	#include <net/route.h>
	56	#include <netinet/in.h>
	57	#include <netinet/in_systm.h>
	58	#include <netinet/if_ether.h>
	59	#include <netinet/ip.h>
	60	#include <netinet/ip_var.h>
	61	#include <netinet/udp.h>
	62	#include <netinet/udp_var.h>
	63	#include <netinet/ip_icmp.h>
	64	#include <netinet/bootp.h>
	65	#include <sys/systm.h>
	66	#include <sys/malloc.h>
9bccf70c	67	#include <netinet/dhcp_options.h>
1c79356b A	68
	69	#ifdef BOOTP_DEBUG
	70	#define dprintf(x) printf x;
55e303ae	71	#else /* !BOOTP_DEBUG */
1c79356b	72	#define dprintf(x)
55e303ae	73	#endif /* BOOTP_DEBUG */
1c79356b A	74
	75	/* ip address formatting macros */
	76	#define IP_FORMAT "%d.%d.%d.%d"
	77	#define IP_CH(ip) ((u_char *)ip)
	78	#define IP_LIST(ip) IP_CH(ip)[0],IP_CH(ip)[1],IP_CH(ip)[2],IP_CH(ip)[3]
	79
9bccf70c A	80	static __inline__ struct sockaddr_in
	81	blank_sin()
	82	{
	83	struct sockaddr_in blank = { sizeof(struct sockaddr_in), AF_INET };
	84	return (blank);
	85	}
1c79356b A	86
	87	static __inline__ void
	88	print_reply(struct bootp *bp, int bp_len)
	89	{
	90	int i, j, len;
	91
	92	printf("bp_op = ");
	93	if (bp->bp_op == BOOTREQUEST) printf("BOOTREQUEST\n");
	94	else if (bp->bp_op == BOOTREPLY) printf("BOOTREPLY\n");
	95	else
	96	{
	97	i = bp->bp_op;
	98	printf("%d\n", i);
	99	}
	100
	101	i = bp->bp_htype;
	102	printf("bp_htype = %d\n", i);
	103
	104	len = bp->bp_hlen;
	105	printf("bp_hlen = %d\n", len);
	106
	107	i = bp->bp_hops;
	108	printf("bp_hops = %d\n", i);
	109
	110	printf("bp_xid = %lu\n", bp->bp_xid);
	111
	112	printf("bp_secs = %u\n", bp->bp_secs);
	113
	114	printf("bp_ciaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_ciaddr));
	115	printf("bp_yiaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_yiaddr));
	116	printf("bp_siaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_siaddr));
	117	printf("bp_giaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_giaddr));
	118
	119	printf("bp_chaddr = ");
	120	for (j = 0; j < len; j++)
	121	{
	122	i = bp->bp_chaddr[j];
	123	printf("%0x", i);
	124	if (j < (len - 1)) printf(":");
	125	}
	126	printf("\n");
	127
	128	printf("bp_sname = %s\n", bp->bp_sname);
	129	printf("bp_file = %s\n", bp->bp_file);
	130	}
	131
	132	static __inline__ void
	133	print_reply_short(struct bootp *bp, int bp_len)
	134	{
	135	printf("bp_yiaddr = " IP_FORMAT "\n", IP_LIST(&bp->bp_yiaddr));
	136	printf("bp_sname = %s\n", bp->bp_sname);
	137	}
	138
	139
	140	static __inline__ long
	141	random_range(long bottom, long top)
	142	{
	143	long number = top - bottom + 1;
	144	long range_size = LONG_MAX / number;
	145	return (((long)random()) / range_size + bottom);
	146	}
	147
	148	/*
	149	* Function: make_bootp_request
150	* Purpose:
151	* Create a "blank" bootp packet.
152	*/
153	static void
154	make_bootp_request(struct bootp_packet * pkt,
155	u_char * hwaddr, u_char hwtype, u_char hwlen)
156	{
9bccf70c A	157	char rfc_magic[4] = RFC_OPTIONS_MAGIC;
9bccf70c A	158
1c79356b A	159	bzero(pkt, sizeof (*pkt));
	160	pkt->bp_ip.ip_v = IPVERSION;
	161	pkt->bp_ip.ip_hl = sizeof (struct ip) >> 2;
9bccf70c A	162	#ifdef RANDOM_IP_ID
	163	pkt->bp_ip.ip_id = ip_randomid();
	164	#else
1c79356b	165	pkt->bp_ip.ip_id = htons(ip_id++);
9bccf70c	166	#endif
1c79356b A	167	pkt->bp_ip.ip_ttl = MAXTTL;
	168	pkt->bp_ip.ip_p = IPPROTO_UDP;
	169	pkt->bp_ip.ip_src.s_addr = 0;
	170	pkt->bp_ip.ip_dst.s_addr = htonl(INADDR_BROADCAST);
	171	pkt->bp_udp.uh_sport = htons(IPPORT_BOOTPC);
	172	pkt->bp_udp.uh_dport = htons(IPPORT_BOOTPS);
	173	pkt->bp_udp.uh_sum = 0;
	174	pkt->bp_bootp.bp_op = BOOTREQUEST;
	175	pkt->bp_bootp.bp_htype = hwtype;
	176	pkt->bp_bootp.bp_hlen = hwlen;
	177	pkt->bp_bootp.bp_ciaddr.s_addr = 0;
	178	bcopy(hwaddr, pkt->bp_bootp.bp_chaddr, hwlen);
	179	bcopy(rfc_magic, pkt->bp_bootp.bp_vend, sizeof(rfc_magic));
9bccf70c	180	pkt->bp_bootp.bp_vend[4] = dhcptag_end_e;
1c79356b A	181	pkt->bp_udp.uh_ulen = htons(sizeof(pkt->bp_udp) + sizeof(pkt->bp_bootp));
	182	pkt->bp_ip.ip_len = htons(sizeof(struct ip) + ntohs(pkt->bp_udp.uh_ulen));
	183	pkt->bp_ip.ip_sum = 0;
	184	return;
	185	}
	186
	187	/*
	188	* Function: ip_pkt_to_mbuf
	189	* Purpose:
	190	* Put the given IP packet into an mbuf, calculate the
	191	* IP checksum.
	192	*/
	193	struct mbuf *
	194	ip_pkt_to_mbuf(caddr_t pkt, int pktsize)
	195	{
	196	struct ip * ip;
	197	struct mbuf * m;
	198
	199	m = (struct mbuf *)m_devget(pkt, pktsize, 0, 0, 0);
	200	if (m == 0) {
	201	printf("bootp: ip_pkt_to_mbuf: m_devget failed\n");
	202	return 0;
	203	}
	204	m->m_flags \|= M_BCAST;
	205	/* Compute the checksum */
	206	ip = mtod(m, struct ip *);
	207	ip->ip_sum = 0;
	208	ip->ip_sum = in_cksum(m, sizeof (struct ip));
	209	return (m);
	210	}
	211
	212	static __inline__ u_char *
	213	link_address(struct sockaddr_dl * dl_p)
	214	{
	215	return (dl_p->sdl_data + dl_p->sdl_nlen);
	216	}
	217
	218	static __inline__ void
	219	link_print(struct sockaddr_dl * dl_p)
	220	{
	221	int i;
	222
	223	#if 0
	224	printf("len %d index %d family %d type 0x%x nlen %d alen %d"
	225	" slen %d addr ", dl_p->sdl_len,
	226	dl_p->sdl_index, dl_p->sdl_family, dl_p->sdl_type,
	227	dl_p->sdl_nlen, dl_p->sdl_alen, dl_p->sdl_slen);
55e303ae	228	#endif
1c79356b A	229	for (i = 0; i < dl_p->sdl_alen; i++)
	230	printf("%s%x", i ? ":" : "",
	231	(link_address(dl_p))[i]);
	232	printf("\n");
	233	return;
	234	}
	235
	236	static struct sockaddr_dl *
	237	link_from_ifnet(struct ifnet * ifp)
	238	{
	239	struct ifaddr * addr;
	240
	241	/* for (addr = ifp->if_addrlist; addr; addr = addr->ifa_next) */
	242
	243	TAILQ_FOREACH(addr, &ifp->if_addrhead, ifa_link) {
	244	if (addr->ifa_addr->sa_family == AF_LINK) {
	245	struct sockaddr_dl * dl_p = (struct sockaddr_dl *)(addr->ifa_addr);
	246
	247	return (dl_p);
	248	}
	249	}
	250	return (NULL);
	251	}
	252
	253	/*
	254	* Function: send_bootp_request
	255	* Purpose:
	256	* Send the request by calling the interface's output routine
	257	* bypassing routing code.
	258	*/
	259	static int
	260	send_bootp_request(struct ifnet * ifp, struct socket * so,
	261	struct bootp_packet * pkt)
	262	{
	263	struct mbuf * m;
	264	struct sockaddr_in sin;
	265
	266	/* Address to send to */
9bccf70c	267	sin = blank_sin();
1c79356b A	268	sin.sin_port = htons(IPPORT_BOOTPS);
	269	sin.sin_addr.s_addr = INADDR_BROADCAST;
	270
	271	m = ip_pkt_to_mbuf((caddr_t)pkt, sizeof(*pkt));
55e303ae	272	return (dlil_output(ifptodlt(ifp, PF_INET), m, 0, (struct sockaddr *)&sin, 0));
1c79356b A	273	}
	274
	275	/*
	276	* Function: receive_packet
	277	* Purpose:
	278	* Return a received packet or an error if none available.
	279	*/
	280	int
9bccf70c	281	receive_packet(struct socket * so, caddr_t pp, int psize, int * actual_size)
1c79356b A	282	{
	283	struct iovec aiov;
	284	struct uio auio;
	285	int rcvflg;
	286	int error;
	287
	288	aiov.iov_base = pp;
	289	aiov.iov_len = psize;
	290	auio.uio_iov = &aiov;
	291	auio.uio_iovcnt = 1;
	292	auio.uio_segflg = UIO_SYSSPACE;
	293	auio.uio_offset = 0;
	294	auio.uio_resid = psize;
	295	auio.uio_rw = UIO_READ;
	296	rcvflg = MSG_WAITALL;
	297
	298	error = soreceive(so, (struct sockaddr **) 0, &auio, 0, 0, &rcvflg);
9bccf70c	299	*actual_size = psize - auio.uio_resid;
1c79356b A	300	return (error);
	301	}
	302
	303	/*
	304	* Function: bootp_timeout
	305	* Purpose:
	306	* Wakeup the process waiting for something on a socket.
	307	*/
	308	static void
9bccf70c	309	bootp_timeout(void * arg)
1c79356b	310	{
9bccf70c	311	struct socket * * socketflag = (struct socket * *)arg;
1c79356b A	312	struct socket * so = *socketflag;
	313	boolean_t funnel_state;
	314
	315	dprintf(("bootp: timeout\n"));
	316
	317	funnel_state = thread_funnel_set(network_flock,TRUE);
	318	*socketflag = NULL;
	319	sowakeup(so, &so->so_rcv);
	320	(void) thread_funnel_set(network_flock, FALSE);
	321	return;
	322	}
	323
1c79356b A	324	/*
	325	* Function: rate_packet
	326	* Purpose:
	327	* Return an integer point rating value for the given bootp packet.
	328	* If yiaddr non-zero, the packet gets a rating of 1.
	329	* Another point is given if the packet contains the subnet mask,
	330	* and another if the router is present.
	331	*/
	332	#define GOOD_RATING 3
	333	static __inline__ int
9bccf70c	334	rate_packet(struct bootp * pkt, int pkt_size, dhcpol_t * options_p)
1c79356b	335	{
9bccf70c A	336	int len;
9bccf70c A	337	int rating = 1;
1c79356b	338
9bccf70c A	339	if (dhcpol_find(options_p, dhcptag_subnet_mask_e, &len, NULL) != NULL) {
	340	rating++;
	341	}
	342	if (dhcpol_find(options_p, dhcptag_router_e, &len, NULL) != NULL) {
1c79356b	343	rating++;
1c79356b A	344	}
	345	return (rating);
	346	}
	347
	348	#define INITIAL_WAIT_SECS 4
	349	#define MAX_WAIT_SECS 64
	350	#define GATHER_TIME_SECS 2
	351	#define RAND_TICKS (hz) /* one second */
	352
	353	/*
	354	* Function: bootp_loop
	355	* Purpose:
	356	* Do the actual BOOTP protocol.
	357	* The algorithm sends out a packet, waits for a response.
	358	* We try max_try times, waiting in an exponentially increasing
	359	* amount of time. Once we receive a good response, we start
	360	* a new time period called the "gather time", during which we
	361	* either find the perfect packet (one that has ip, mask and router)
	362	* or we continue to gather responses. At the end of the gather period,
	363	* we use the best response gathered.
	364	*/
	365	static int
	366	bootp_loop(struct socket * so, struct ifnet * ifp, int max_try,
	367	struct in_addr * iaddr_p, struct in_addr * netmask_p,
	368	struct in_addr * router_p)
	369	{
	370	struct timeval current_time;
	371	struct sockaddr_dl * dl_p;
	372	int error = 0;
	373	char * hwaddr;
	374	int hwlen;
	375	char hwtype = 0;
	376	struct bootp_packet * request = NULL;
	377	struct bootp * reply = NULL;
9bccf70c	378	int reply_size = DHCP_PACKET_MIN;
1c79356b A	379	struct timeval start_time;
	380	u_long xid;
	381	int retry;
	382	struct socket * timeflag;
	383	int wait_ticks = INITIAL_WAIT_SECS * hz;
	384
	385	/* get the hardware address from the interface */
	386	dl_p = link_from_ifnet(ifp);
	387	if (dl_p == NULL) {
	388	printf("bootp: can't get link address\n");
	389	return (ENXIO);
	390	}
	391
	392	printf("bootp: h/w addr ");
	393	link_print(dl_p);
	394
	395	hwaddr = link_address(dl_p);
	396	hwlen = dl_p->sdl_alen;
	397	switch (dl_p->sdl_type) {
	398	case IFT_ETHER:
	399	hwtype = ARPHRD_ETHER;
	400	break;
	401	default:
	402	printf("bootp: hardware type %d not supported\n",
	403	dl_p->sdl_type);
	404	panic("bootp: hardware type not supported");
	405	break;
	406	}
	407
	408	/* set transaction id and remember the start time */
	409	microtime(&start_time);
	410	current_time = start_time;
	411	xid = random();
	412
	413	/* make a request/reply packet */
	414	request = (struct bootp_packet )kalloc(sizeof(request));
	415	make_bootp_request(request, hwaddr, hwtype, hwlen);
9bccf70c	416	reply = (struct bootp *)kalloc(reply_size);
1c79356b A	417	iaddr_p->s_addr = 0;
	418	printf("bootp: sending request");
	419	for (retry = 0; retry < max_try; retry++) {
	420	int gather_count = 0;
	421	int last_rating = 0;
	422
	423	/* Send the request */
	424	printf(".");
	425	request->bp_bootp.bp_secs = htons((u_short)(current_time.tv_sec
	426	- start_time.tv_sec));
	427	request->bp_bootp.bp_xid = htonl(xid);
	428	error = send_bootp_request(ifp, so, request);
	429	if (error)
	430	goto cleanup;
	431
	432	timeflag = so;
	433	wait_ticks += random_range(-RAND_TICKS, RAND_TICKS);
	434	dprintf(("bootp: waiting %d ticks\n", wait_ticks));
9bccf70c	435	timeout((timeout_fcn_t)bootp_timeout, &timeflag, wait_ticks);
1c79356b A	436
1c79356b A	437	while (TRUE) {
9bccf70c A	438	int n = 0;
	439
	440	error = receive_packet(so, (caddr_t)reply, reply_size, &n);
1c79356b A	441	if (error == 0) {
	442	dprintf(("\nbootp: received packet\n"));
	443	if (ntohl(reply->bp_xid) == xid
	444	&& reply->bp_yiaddr.s_addr
	445	&& bcmp(reply->bp_chaddr, hwaddr, hwlen) == 0) {
9bccf70c A	446	int rating;
	447	dhcpol_t options;
	448
1c79356b	449	#ifdef BOOTP_DEBUG
9bccf70c	450	print_reply_short(reply, n);
55e303ae	451	#endif /* BOOTP_DEBUG */
9bccf70c A	452	(void)dhcpol_parse_packet(&options, (struct dhcp *)reply,
	453	n, NULL);
	454	rating = rate_packet(reply, n, &options);
	455	if (rating > last_rating) {
	456	struct in_addr * ip;
	457	int len;
	458
	459	*iaddr_p = reply->bp_yiaddr;
	460	ip = (struct in_addr *)
	461	dhcpol_find(&options,
	462	dhcptag_subnet_mask_e, &len, NULL);
	463	if (ip) {
	464	netmask_p = ip;
	465	}
	466	ip = (struct in_addr *)
	467	dhcpol_find(&options, dhcptag_router_e, &len, NULL);
	468	if (ip) {
	469	router_p = ip;
	470	}
	471	printf("%sbootp: got "
	472	"response from %s (" IP_FORMAT ")\n",
	473	last_rating == 0 ? "\n" : "",
	474	reply->bp_sname,
	475	IP_LIST(&reply->bp_siaddr));
	476	}
	477	dhcpol_free(&options);
1c79356b	478	if (rating >= GOOD_RATING) {
9bccf70c A	479	untimeout((timeout_fcn_t)bootp_timeout, &timeflag);
9bccf70c A	480	goto done;
1c79356b A	481	}
1c79356b A	482	if (gather_count == 0) {
9bccf70c	483	untimeout((timeout_fcn_t)bootp_timeout, &timeflag);
1c79356b	484	timeflag = so;
9bccf70c	485	timeout((timeout_fcn_t)bootp_timeout, &timeflag,
1c79356b A	486	hz * GATHER_TIME_SECS);
	487	}
	488	gather_count++;
	489	}
	490	else {
	491	dprintf(("bootp: packet ignored\n"));
	492	}
	493	}
	494	else if ((error != EWOULDBLOCK)) {
	495	break;
	496	}
	497	else if (timeflag == NULL) { /* timed out */
	498	if (gather_count) {
	499	dprintf(("bootp: gathering time has expired"));
9bccf70c	500	goto done; /* we have a packet */
1c79356b A	501	}
	502	break; /* retry */
	503	}
	504	else
	505	sbwait(&so->so_rcv);
	506	}
	507	if (error && (error != EWOULDBLOCK)) {
	508	dprintf(("bootp: failed to receive packets: %d\n", error));
9bccf70c	509	untimeout((timeout_fcn_t)bootp_timeout, &timeflag);
1c79356b A	510	goto cleanup;
	511	}
	512	wait_ticks *= 2;
	513	if (wait_ticks > (MAX_WAIT_SECS * hz))
	514	wait_ticks = MAX_WAIT_SECS * hz;
	515	xid++;
	516	microtime(&current_time);
	517	}
	518	error = ETIMEDOUT;
	519	goto cleanup;
	520
9bccf70c	521	done:
1c79356b	522	error = 0;
1c79356b A	523
	524	cleanup:
	525	if (request)
	526	kfree((caddr_t)request, sizeof (*request));
	527	if (reply)
9bccf70c	528	kfree((caddr_t)reply, reply_size);
1c79356b A	529	return (error);
	530	}
	531
	532	/*
	533	* Routine: bootp
	534	* Function:
	535	* Use the BOOTP protocol to resolve what our IP address should be
	536	* on a particular interface.
	537	*/
	538	int bootp(struct ifnet * ifp, struct in_addr * iaddr_p, int max_try,
	539	struct in_addr * netmask_p, struct in_addr * router_p,
	540	struct proc * procp)
	541	{
	542	boolean_t addr_set = FALSE;
	543	struct ifreq ifr;
	544	int error;
	545	struct socket * so = NULL;
	546
	547	/* get a socket */
	548	error = socreate(AF_INET, &so, SOCK_DGRAM, 0);
	549	if (error) {
	550	dprintf(("bootp: socreate failed %d\n", error));
	551	return (error);
	552	}
	553
	554	/* assign the all-zeroes address */
	555	bzero(&ifr, sizeof(ifr));
	556	sprintf(ifr.ifr_name, "%s%d", ifp->if_name, ifp->if_unit);
9bccf70c	557	((struct sockaddr_in )&ifr.ifr_addr) = blank_sin();
1c79356b A	558	error = ifioctl(so, SIOCSIFADDR, (caddr_t)&ifr, procp);
	559	if (error) {
	560	dprintf(("bootp: SIOCSIFADDR all-zeroes IP failed: %d\n",
	561	error));
	562	goto cleanup;
	563	}
	564	dprintf(("bootp: all-zeroes IP address assigned\n"));
	565	addr_set = TRUE;
	566
	567	{ /* bind the socket */
	568	struct sockaddr_in * sin;
	569
0b4e3aa0 A	570	sin = _MALLOC(sizeof(struct sockaddr_in), M_IFADDR, M_WAIT);
	571	if (sin == NULL) {
	572	error = ENOMEM;
	573	goto cleanup;
	574	}
1c79356b A	575	sin->sin_len = sizeof(struct sockaddr_in);
	576	sin->sin_family = AF_INET;
	577	sin->sin_port = htons(IPPORT_BOOTPC);
	578	sin->sin_addr.s_addr = INADDR_ANY;
	579	error = sobind(so, (struct sockaddr *) sin);
	580
	581	FREE(sin, M_IFADDR);
	582	if (error) {
	583	dprintf(("bootp: sobind failed, %d\n", error));
	584	goto cleanup;
	585	}
	586	so->so_state \|= SS_NBIO;
	587	}
	588	/* do the protocol */
	589	error = bootp_loop(so, ifp, max_try, iaddr_p, netmask_p, router_p);
	590
	591	cleanup:
	592	if (so) {
	593	if (addr_set) {
	594	(void) ifioctl(so, SIOCDIFADDR, (caddr_t) &ifr, procp);
	595	}
	596	soclose(so);
	597	}
	598	return (error);
	599	}