| Current Path : /usr/src/sbin/dhclient/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/sbin/dhclient/options.c |
/* $OpenBSD: options.c,v 1.15 2004/12/26 03:17:07 deraadt Exp $ */
/* DHCP options parsing and reassembly. */
/*
* Copyright (c) 1995, 1996, 1997, 1998 The Internet Software Consortium.
* All rights reserved.
*
* 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. Neither the name of The Internet Software Consortium 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 INTERNET SOFTWARE CONSORTIUM 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 INTERNET SOFTWARE CONSORTIUM 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.
*
* This software has been written for the Internet Software Consortium
* by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
* Enterprises. To learn more about the Internet Software Consortium,
* see ``http://www.vix.com/isc''. To learn more about Vixie
* Enterprises, see ``http://www.vix.com''.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/sbin/dhclient/options.c 230597 2012-01-26 19:46:13Z dumbbell $");
#include <ctype.h>
#define DHCP_OPTION_DATA
#include "dhcpd.h"
int bad_options = 0;
int bad_options_max = 5;
void parse_options(struct packet *);
void parse_option_buffer(struct packet *, unsigned char *, int);
int store_options(unsigned char *, int, struct tree_cache **,
unsigned char *, int, int, int, int);
void expand_domain_search(struct packet *packet);
int find_search_domain_name_len(struct option_data *option, int *offset);
void expand_search_domain_name(struct option_data *option, int *offset,
unsigned char **domain_search);
/*
* Parse all available options out of the specified packet.
*/
void
parse_options(struct packet *packet)
{
/* Initially, zero all option pointers. */
memset(packet->options, 0, sizeof(packet->options));
/* If we don't see the magic cookie, there's nothing to parse. */
if (memcmp(packet->raw->options, DHCP_OPTIONS_COOKIE, 4)) {
packet->options_valid = 0;
return;
}
/*
* Go through the options field, up to the end of the packet or
* the End field.
*/
parse_option_buffer(packet, &packet->raw->options[4],
packet->packet_length - DHCP_FIXED_NON_UDP - 4);
/*
* If we parsed a DHCP Option Overload option, parse more
* options out of the buffer(s) containing them.
*/
if (packet->options_valid &&
packet->options[DHO_DHCP_OPTION_OVERLOAD].data) {
if (packet->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 1)
parse_option_buffer(packet,
(unsigned char *)packet->raw->file,
sizeof(packet->raw->file));
if (packet->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 2)
parse_option_buffer(packet,
(unsigned char *)packet->raw->sname,
sizeof(packet->raw->sname));
}
/* Expand DHCP Domain Search option. */
if (packet->options_valid) {
expand_domain_search(packet);
}
}
/*
* Parse options out of the specified buffer, storing addresses of
* option values in packet->options and setting packet->options_valid if
* no errors are encountered.
*/
void
parse_option_buffer(struct packet *packet,
unsigned char *buffer, int length)
{
unsigned char *s, *t, *end = buffer + length;
int len, code;
for (s = buffer; *s != DHO_END && s < end; ) {
code = s[0];
/* Pad options don't have a length - just skip them. */
if (code == DHO_PAD) {
s++;
continue;
}
if (s + 2 > end) {
len = 65536;
goto bogus;
}
/*
* All other fields (except end, see above) have a
* one-byte length.
*/
len = s[1];
/*
* If the length is outrageous, silently skip the rest,
* and mark the packet bad. Unfortunately some crappy
* dhcp servers always seem to give us garbage on the
* end of a packet. so rather than keep refusing, give
* up and try to take one after seeing a few without
* anything good.
*/
if (s + len + 2 > end) {
bogus:
bad_options++;
warning("option %s (%d) %s.",
dhcp_options[code].name, len,
"larger than buffer");
if (bad_options == bad_options_max) {
packet->options_valid = 1;
bad_options = 0;
warning("Many bogus options seen in offers. "
"Taking this offer in spite of bogus "
"options - hope for the best!");
} else {
warning("rejecting bogus offer.");
packet->options_valid = 0;
}
return;
}
/*
* If we haven't seen this option before, just make
* space for it and copy it there.
*/
if (!packet->options[code].data) {
if (!(t = calloc(1, len + 1)))
error("Can't allocate storage for option %s.",
dhcp_options[code].name);
/*
* Copy and NUL-terminate the option (in case
* it's an ASCII string.
*/
memcpy(t, &s[2], len);
t[len] = 0;
packet->options[code].len = len;
packet->options[code].data = t;
} else {
/*
* If it's a repeat, concatenate it to whatever
* we last saw. This is really only required
* for clients, but what the heck...
*/
t = calloc(1, len + packet->options[code].len + 1);
if (!t)
error("Can't expand storage for option %s.",
dhcp_options[code].name);
memcpy(t, packet->options[code].data,
packet->options[code].len);
memcpy(t + packet->options[code].len,
&s[2], len);
packet->options[code].len += len;
t[packet->options[code].len] = 0;
free(packet->options[code].data);
packet->options[code].data = t;
}
s += len + 2;
}
packet->options_valid = 1;
}
/*
* Expand DHCP Domain Search option. The value of this option is
* encoded like DNS' list of labels. See:
* RFC 3397
* RFC 1035
*/
void
expand_domain_search(struct packet *packet)
{
int offset, expanded_len, next_domain_len;
struct option_data *option;
unsigned char *domain_search, *cursor;
if (packet->options[DHO_DOMAIN_SEARCH].data == NULL)
return;
option = &packet->options[DHO_DOMAIN_SEARCH];
/* Compute final expanded length. */
expanded_len = 0;
offset = 0;
while (offset < option->len) {
next_domain_len = find_search_domain_name_len(option, &offset);
if (next_domain_len < 0)
/* The Domain Search option value is invalid. */
return;
/* We add 1 for the space between domain names. */
expanded_len += next_domain_len + 1;
}
if (expanded_len > 0)
/* Remove 1 for the superfluous trailing space. */
--expanded_len;
domain_search = malloc(expanded_len + 1);
if (domain_search == NULL)
error("Can't allocate storage for expanded domain-search\n");
offset = 0;
cursor = domain_search;
while (offset < option->len) {
expand_search_domain_name(option, &offset, &cursor);
cursor[0] = ' ';
cursor++;
}
domain_search[expanded_len] = '\0';
free(option->data);
option->len = expanded_len;
option->data = domain_search;
}
int
find_search_domain_name_len(struct option_data *option, int *offset)
{
int domain_name_len, i, label_len, pointer, pointed_len;
domain_name_len = 0;
i = *offset;
while (i < option->len) {
label_len = option->data[i];
if (label_len == 0) {
/*
* A zero-length label marks the end of this
* domain name.
*/
*offset = i + 1;
return (domain_name_len);
} else if (label_len & 0xC0) {
/* This is a pointer to another list of labels. */
if (i + 1 >= option->len) {
/* The pointer is truncated. */
warning("Truncated pointer in DHCP Domain "
"Search option.");
return (-1);
}
pointer = ((label_len & ~(0xC0)) << 8) +
option->data[i + 1];
if (pointer >= *offset) {
/*
* The pointer must indicates a prior
* occurance.
*/
warning("Invalid forward pointer in DHCP "
"Domain Search option compression.");
return (-1);
}
pointed_len = find_search_domain_name_len(option,
&pointer);
domain_name_len += pointed_len;
*offset = i + 2;
return (domain_name_len);
}
if (i + label_len >= option->len) {
warning("Truncated label in DHCP Domain Search "
"option.");
return (-1);
}
/*
* Update the domain name length with the length of the
* current label, plus a trailing dot ('.').
*/
domain_name_len += label_len + 1;
/* Move cursor. */
i += label_len + 1;
}
warning("Truncated DHCP Domain Search option.");
return (-1);
}
void
expand_search_domain_name(struct option_data *option, int *offset,
unsigned char **domain_search)
{
int i, label_len, pointer;
unsigned char *cursor;
/*
* This is the same loop than the function above
* (find_search_domain_name_len). Therefore, we remove checks,
* they're already done. Here, we just make the copy.
*/
i = *offset;
cursor = *domain_search;
while (i < option->len) {
label_len = option->data[i];
if (label_len == 0) {
/*
* A zero-length label marks the end of this
* domain name.
*/
*offset = i + 1;
*domain_search = cursor;
return;
} else if (label_len & 0xC0) {
/* This is a pointer to another list of labels. */
pointer = ((label_len & ~(0xC0)) << 8) +
option->data[i + 1];
expand_search_domain_name(option, &pointer, &cursor);
*offset = i + 2;
*domain_search = cursor;
return;
}
/* Copy the label found. */
memcpy(cursor, option->data + i + 1, label_len);
cursor[label_len] = '.';
/* Move cursor. */
i += label_len + 1;
cursor += label_len + 1;
}
}
/*
* cons options into a big buffer, and then split them out into the
* three separate buffers if needed. This allows us to cons up a set of
* vendor options using the same routine.
*/
int
cons_options(struct packet *inpacket, struct dhcp_packet *outpacket,
int mms, struct tree_cache **options,
int overload, /* Overload flags that may be set. */
int terminate, int bootpp, u_int8_t *prl, int prl_len)
{
unsigned char priority_list[300], buffer[4096];
int priority_len, main_buffer_size, mainbufix, bufix;
int option_size, length;
/*
* If the client has provided a maximum DHCP message size, use
* that; otherwise, if it's BOOTP, only 64 bytes; otherwise use
* up to the minimum IP MTU size (576 bytes).
*
* XXX if a BOOTP client specifies a max message size, we will
* honor it.
*/
if (!mms &&
inpacket &&
inpacket->options[DHO_DHCP_MAX_MESSAGE_SIZE].data &&
(inpacket->options[DHO_DHCP_MAX_MESSAGE_SIZE].len >=
sizeof(u_int16_t)))
mms = getUShort(
inpacket->options[DHO_DHCP_MAX_MESSAGE_SIZE].data);
if (mms)
main_buffer_size = mms - DHCP_FIXED_LEN;
else if (bootpp)
main_buffer_size = 64;
else
main_buffer_size = 576 - DHCP_FIXED_LEN;
if (main_buffer_size > sizeof(buffer))
main_buffer_size = sizeof(buffer);
/* Preload the option priority list with mandatory options. */
priority_len = 0;
priority_list[priority_len++] = DHO_DHCP_MESSAGE_TYPE;
priority_list[priority_len++] = DHO_DHCP_SERVER_IDENTIFIER;
priority_list[priority_len++] = DHO_DHCP_LEASE_TIME;
priority_list[priority_len++] = DHO_DHCP_MESSAGE;
/*
* If the client has provided a list of options that it wishes
* returned, use it to prioritize. Otherwise, prioritize based
* on the default priority list.
*/
if (inpacket &&
inpacket->options[DHO_DHCP_PARAMETER_REQUEST_LIST].data) {
int prlen =
inpacket->options[DHO_DHCP_PARAMETER_REQUEST_LIST].len;
if (prlen + priority_len > sizeof(priority_list))
prlen = sizeof(priority_list) - priority_len;
memcpy(&priority_list[priority_len],
inpacket->options[DHO_DHCP_PARAMETER_REQUEST_LIST].data,
prlen);
priority_len += prlen;
prl = priority_list;
} else if (prl) {
if (prl_len + priority_len > sizeof(priority_list))
prl_len = sizeof(priority_list) - priority_len;
memcpy(&priority_list[priority_len], prl, prl_len);
priority_len += prl_len;
prl = priority_list;
} else {
memcpy(&priority_list[priority_len],
dhcp_option_default_priority_list,
sizeof_dhcp_option_default_priority_list);
priority_len += sizeof_dhcp_option_default_priority_list;
}
/* Copy the options into the big buffer... */
option_size = store_options(
buffer,
(main_buffer_size - 7 + ((overload & 1) ? DHCP_FILE_LEN : 0) +
((overload & 2) ? DHCP_SNAME_LEN : 0)),
options, priority_list, priority_len, main_buffer_size,
(main_buffer_size + ((overload & 1) ? DHCP_FILE_LEN : 0)),
terminate);
/* Put the cookie up front... */
memcpy(outpacket->options, DHCP_OPTIONS_COOKIE, 4);
mainbufix = 4;
/*
* If we're going to have to overload, store the overload option
* at the beginning. If we can, though, just store the whole
* thing in the packet's option buffer and leave it at that.
*/
if (option_size <= main_buffer_size - mainbufix) {
memcpy(&outpacket->options[mainbufix],
buffer, option_size);
mainbufix += option_size;
if (mainbufix < main_buffer_size)
outpacket->options[mainbufix++] = DHO_END;
length = DHCP_FIXED_NON_UDP + mainbufix;
} else {
outpacket->options[mainbufix++] = DHO_DHCP_OPTION_OVERLOAD;
outpacket->options[mainbufix++] = 1;
if (option_size >
main_buffer_size - mainbufix + DHCP_FILE_LEN)
outpacket->options[mainbufix++] = 3;
else
outpacket->options[mainbufix++] = 1;
memcpy(&outpacket->options[mainbufix],
buffer, main_buffer_size - mainbufix);
bufix = main_buffer_size - mainbufix;
length = DHCP_FIXED_NON_UDP + mainbufix;
if (overload & 1) {
if (option_size - bufix <= DHCP_FILE_LEN) {
memcpy(outpacket->file,
&buffer[bufix], option_size - bufix);
mainbufix = option_size - bufix;
if (mainbufix < DHCP_FILE_LEN)
outpacket->file[mainbufix++] = (char)DHO_END;
while (mainbufix < DHCP_FILE_LEN)
outpacket->file[mainbufix++] = (char)DHO_PAD;
} else {
memcpy(outpacket->file,
&buffer[bufix], DHCP_FILE_LEN);
bufix += DHCP_FILE_LEN;
}
}
if ((overload & 2) && option_size < bufix) {
memcpy(outpacket->sname,
&buffer[bufix], option_size - bufix);
mainbufix = option_size - bufix;
if (mainbufix < DHCP_SNAME_LEN)
outpacket->file[mainbufix++] = (char)DHO_END;
while (mainbufix < DHCP_SNAME_LEN)
outpacket->file[mainbufix++] = (char)DHO_PAD;
}
}
return (length);
}
/*
* Store all the requested options into the requested buffer.
*/
int
store_options(unsigned char *buffer, int buflen, struct tree_cache **options,
unsigned char *priority_list, int priority_len, int first_cutoff,
int second_cutoff, int terminate)
{
int bufix = 0, option_stored[256], i, ix, tto;
/* Zero out the stored-lengths array. */
memset(option_stored, 0, sizeof(option_stored));
/*
* Copy out the options in the order that they appear in the
* priority list...
*/
for (i = 0; i < priority_len; i++) {
/* Code for next option to try to store. */
int code = priority_list[i];
int optstart;
/*
* Number of bytes left to store (some may already have
* been stored by a previous pass).
*/
int length;
/* If no data is available for this option, skip it. */
if (!options[code]) {
continue;
}
/*
* The client could ask for things that are mandatory,
* in which case we should avoid storing them twice...
*/
if (option_stored[code])
continue;
option_stored[code] = 1;
/* We should now have a constant length for the option. */
length = options[code]->len;
/* Do we add a NUL? */
if (terminate && dhcp_options[code].format[0] == 't') {
length++;
tto = 1;
} else
tto = 0;
/* Try to store the option. */
/*
* If the option's length is more than 255, we must
* store it in multiple hunks. Store 255-byte hunks
* first. However, in any case, if the option data will
* cross a buffer boundary, split it across that
* boundary.
*/
ix = 0;
optstart = bufix;
while (length) {
unsigned char incr = length > 255 ? 255 : length;
/*
* If this hunk of the buffer will cross a
* boundary, only go up to the boundary in this
* pass.
*/
if (bufix < first_cutoff &&
bufix + incr > first_cutoff)
incr = first_cutoff - bufix;
else if (bufix < second_cutoff &&
bufix + incr > second_cutoff)
incr = second_cutoff - bufix;
/*
* If this option is going to overflow the
* buffer, skip it.
*/
if (bufix + 2 + incr > buflen) {
bufix = optstart;
break;
}
/* Everything looks good - copy it in! */
buffer[bufix] = code;
buffer[bufix + 1] = incr;
if (tto && incr == length) {
memcpy(buffer + bufix + 2,
options[code]->value + ix, incr - 1);
buffer[bufix + 2 + incr - 1] = 0;
} else
memcpy(buffer + bufix + 2,
options[code]->value + ix, incr);
length -= incr;
ix += incr;
bufix += 2 + incr;
}
}
return (bufix);
}
/*
* Format the specified option so that a human can easily read it.
*/
char *
pretty_print_option(unsigned int code, unsigned char *data, int len,
int emit_commas, int emit_quotes)
{
static char optbuf[32768]; /* XXX */
int hunksize = 0, numhunk = -1, numelem = 0;
char fmtbuf[32], *op = optbuf;
int i, j, k, opleft = sizeof(optbuf);
unsigned char *dp = data;
struct in_addr foo;
char comma;
/* Code should be between 0 and 255. */
if (code > 255)
error("pretty_print_option: bad code %d", code);
if (emit_commas)
comma = ',';
else
comma = ' ';
/* Figure out the size of the data. */
for (i = 0; dhcp_options[code].format[i]; i++) {
if (!numhunk) {
warning("%s: Excess information in format string: %s",
dhcp_options[code].name,
&(dhcp_options[code].format[i]));
break;
}
numelem++;
fmtbuf[i] = dhcp_options[code].format[i];
switch (dhcp_options[code].format[i]) {
case 'A':
--numelem;
fmtbuf[i] = 0;
numhunk = 0;
break;
case 'X':
for (k = 0; k < len; k++)
if (!isascii(data[k]) ||
!isprint(data[k]))
break;
if (k == len) {
fmtbuf[i] = 't';
numhunk = -2;
} else {
fmtbuf[i] = 'x';
hunksize++;
comma = ':';
numhunk = 0;
}
fmtbuf[i + 1] = 0;
break;
case 't':
fmtbuf[i] = 't';
fmtbuf[i + 1] = 0;
numhunk = -2;
break;
case 'I':
case 'l':
case 'L':
hunksize += 4;
break;
case 's':
case 'S':
hunksize += 2;
break;
case 'b':
case 'B':
case 'f':
hunksize++;
break;
case 'e':
break;
default:
warning("%s: garbage in format string: %s",
dhcp_options[code].name,
&(dhcp_options[code].format[i]));
break;
}
}
/* Check for too few bytes... */
if (hunksize > len) {
warning("%s: expecting at least %d bytes; got %d",
dhcp_options[code].name, hunksize, len);
return ("<error>");
}
/* Check for too many bytes... */
if (numhunk == -1 && hunksize < len)
warning("%s: %d extra bytes",
dhcp_options[code].name, len - hunksize);
/* If this is an array, compute its size. */
if (!numhunk)
numhunk = len / hunksize;
/* See if we got an exact number of hunks. */
if (numhunk > 0 && numhunk * hunksize < len)
warning("%s: %d extra bytes at end of array",
dhcp_options[code].name, len - numhunk * hunksize);
/* A one-hunk array prints the same as a single hunk. */
if (numhunk < 0)
numhunk = 1;
/* Cycle through the array (or hunk) printing the data. */
for (i = 0; i < numhunk; i++) {
for (j = 0; j < numelem; j++) {
int opcount;
switch (fmtbuf[j]) {
case 't':
if (emit_quotes) {
*op++ = '"';
opleft--;
}
for (; dp < data + len; dp++) {
if (!isascii(*dp) ||
!isprint(*dp)) {
if (dp + 1 != data + len ||
*dp != 0) {
snprintf(op, opleft,
"\\%03o", *dp);
op += 4;
opleft -= 4;
}
} else if (*dp == '"' ||
*dp == '\'' ||
*dp == '$' ||
*dp == '`' ||
*dp == '\\') {
*op++ = '\\';
*op++ = *dp;
opleft -= 2;
} else {
*op++ = *dp;
opleft--;
}
}
if (emit_quotes) {
*op++ = '"';
opleft--;
}
*op = 0;
break;
case 'I':
foo.s_addr = htonl(getULong(dp));
opcount = strlcpy(op, inet_ntoa(foo), opleft);
if (opcount >= opleft)
goto toobig;
opleft -= opcount;
dp += 4;
break;
case 'l':
opcount = snprintf(op, opleft, "%ld",
(long)getLong(dp));
if (opcount >= opleft || opcount == -1)
goto toobig;
opleft -= opcount;
dp += 4;
break;
case 'L':
opcount = snprintf(op, opleft, "%ld",
(unsigned long)getULong(dp));
if (opcount >= opleft || opcount == -1)
goto toobig;
opleft -= opcount;
dp += 4;
break;
case 's':
opcount = snprintf(op, opleft, "%d",
getShort(dp));
if (opcount >= opleft || opcount == -1)
goto toobig;
opleft -= opcount;
dp += 2;
break;
case 'S':
opcount = snprintf(op, opleft, "%d",
getUShort(dp));
if (opcount >= opleft || opcount == -1)
goto toobig;
opleft -= opcount;
dp += 2;
break;
case 'b':
opcount = snprintf(op, opleft, "%d",
*(char *)dp++);
if (opcount >= opleft || opcount == -1)
goto toobig;
opleft -= opcount;
break;
case 'B':
opcount = snprintf(op, opleft, "%d", *dp++);
if (opcount >= opleft || opcount == -1)
goto toobig;
opleft -= opcount;
break;
case 'x':
opcount = snprintf(op, opleft, "%x", *dp++);
if (opcount >= opleft || opcount == -1)
goto toobig;
opleft -= opcount;
break;
case 'f':
opcount = strlcpy(op,
*dp++ ? "true" : "false", opleft);
if (opcount >= opleft)
goto toobig;
opleft -= opcount;
break;
default:
warning("Unexpected format code %c", fmtbuf[j]);
}
op += strlen(op);
opleft -= strlen(op);
if (opleft < 1)
goto toobig;
if (j + 1 < numelem && comma != ':') {
*op++ = ' ';
opleft--;
}
}
if (i + 1 < numhunk) {
*op++ = comma;
opleft--;
}
if (opleft < 1)
goto toobig;
}
return (optbuf);
toobig:
warning("dhcp option too large");
return ("<error>");
}
void
do_packet(struct interface_info *interface, struct dhcp_packet *packet,
int len, unsigned int from_port, struct iaddr from, struct hardware *hfrom)
{
struct packet tp;
int i;
if (packet->hlen > sizeof(packet->chaddr)) {
note("Discarding packet with invalid hlen.");
return;
}
memset(&tp, 0, sizeof(tp));
tp.raw = packet;
tp.packet_length = len;
tp.client_port = from_port;
tp.client_addr = from;
tp.interface = interface;
tp.haddr = hfrom;
parse_options(&tp);
if (tp.options_valid &&
tp.options[DHO_DHCP_MESSAGE_TYPE].data)
tp.packet_type = tp.options[DHO_DHCP_MESSAGE_TYPE].data[0];
if (tp.packet_type)
dhcp(&tp);
else
bootp(&tp);
/* Free the data associated with the options. */
for (i = 0; i < 256; i++)
if (tp.options[i].len && tp.options[i].data)
free(tp.options[i].data);
}