diff options
Diffstat (limited to 'common/options.c')
| -rw-r--r-- | common/options.c | 520 |
1 files changed, 0 insertions, 520 deletions
diff --git a/common/options.c b/common/options.c deleted file mode 100644 index 354c10a4..00000000 --- a/common/options.c +++ /dev/null @@ -1,520 +0,0 @@ -/* options.c - - DHCP options parsing and reassembly. */ - -/* - * Copyright (c) 1995, 1996 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''. - */ - -#ifndef lint -static char copyright[] = -"@(#) Copyright (c) 1995, 1996 The Internet Software Consortium. All rights reserved.\n"; -#endif /* not lint */ - -#define DHCP_OPTION_DATA -#include "dhcpd.h" - -/* Parse all available options out of the specified packet. */ - -void parse_options (packet) - 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, - packet -> raw -> file, - sizeof packet -> raw -> file); - if (packet -> options [DHO_DHCP_OPTION_OVERLOAD].data [0] & 2) - parse_option_buffer (packet, - packet -> raw -> sname, - sizeof packet -> raw -> sname); - } -} - -/* 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 (packet, buffer, length) - struct packet *packet; - unsigned char *buffer; - int length; -{ - unsigned char *s, *t; - unsigned char *end = buffer + length; - int len; - int 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; - } - /* All other fields (except end, see above) have a - one-byte length. */ - len = s [1]; - - /* If the length is outrageous, the options are bad. */ - if (s + len + 2 > end) { - warn ("Option %s length %d overflows input buffer.", - dhcp_options [code].name, - len); - 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 = (unsigned char *)malloc (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 = (unsigned char *) - malloc (len + packet -> options [code].len); - 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; -} - -/* cons options into a big buffer, and then split them out into the - three seperate buffers if needed. This allows us to cons up a set - of vendor options using the same routine. */ - -void cons_options (inpacket, outpacket, options, overload) - struct packet *inpacket; - struct packet *outpacket; - struct tree_cache **options; - int overload; /* Overload flags that may be set. */ -{ - unsigned char priority_list [300]; - int priority_len; - unsigned char buffer [4096]; /* Really big buffer... */ - int main_buffer_size; - int mainbufix, bufix; - int option_size; - int result; - int i; - - /* If the client has provided a maximum DHCP message size, - use that. Otherwise, we use the default MTU size (576 bytes). */ - /* XXX Maybe it would be safe to assume that we can send a packet - to the client that's as big as the one it sent us, even if it - didn't specify a large MTU. */ - if (inpacket && inpacket -> options [DHO_DHCP_MAX_MESSAGE_SIZE].data) { - main_buffer_size = - (getUShort (inpacket -> options - [DHO_DHCP_MAX_MESSAGE_SIZE].data) - - DHCP_FIXED_LEN); - /* Enforce a minimum packet size... */ - if (main_buffer_size < (576 - DHCP_FIXED_LEN)) - main_buffer_size = 576 - DHCP_FIXED_LEN; - } else - main_buffer_size = 576 - DHCP_FIXED_LEN; - - /* 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) { - memcpy (&priority_list [priority_len], - inpacket -> options - [DHO_DHCP_PARAMETER_REQUEST_LIST].data, - inpacket -> options - [DHO_DHCP_PARAMETER_REQUEST_LIST].len); - priority_len += - inpacket -> options - [DHO_DHCP_PARAMETER_REQUEST_LIST].len; - } 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))); - - /* Put the cookie up front... */ - memcpy (outpacket -> raw -> 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 -> raw -> options [mainbufix], - buffer, option_size); - mainbufix += option_size; - if (mainbufix < main_buffer_size) - outpacket -> raw -> options [mainbufix++] - = DHO_END; - outpacket -> packet_length = DHCP_FIXED_NON_UDP + mainbufix; - } else { - outpacket -> raw -> options [mainbufix++] = - DHO_DHCP_OPTION_OVERLOAD; - outpacket -> raw -> options [mainbufix++] = 1; - if (option_size > main_buffer_size - mainbufix + DHCP_FILE_LEN) - outpacket -> raw -> options [mainbufix++] = 3; - else - outpacket -> raw -> options [mainbufix++] = 1; - - memcpy (&outpacket -> raw -> options [mainbufix], - buffer, main_buffer_size - mainbufix); - bufix = main_buffer_size - mainbufix; - outpacket -> packet_length = DHCP_FIXED_NON_UDP + mainbufix; - if (overload & 1) { - if (option_size - bufix <= DHCP_FILE_LEN) { - memcpy (outpacket -> raw -> file, - &buffer [bufix], option_size - bufix); - mainbufix = option_size - bufix; - if (mainbufix < DHCP_FILE_LEN) - outpacket -> raw -> file [mainbufix++] - = DHO_END; - while (mainbufix < DHCP_FILE_LEN) - outpacket -> raw -> file [mainbufix++] - = DHO_PAD; - } else { - memcpy (outpacket -> raw -> file, - &buffer [bufix], DHCP_FILE_LEN); - bufix += DHCP_FILE_LEN; - } - } - if ((overload & 2) && option_size < bufix) { - memcpy (outpacket -> raw -> sname, - &buffer [bufix], option_size - bufix); - - mainbufix = option_size - bufix; - if (mainbufix < DHCP_SNAME_LEN) - outpacket -> raw -> file [mainbufix++] - = DHO_END; - while (mainbufix < DHCP_SNAME_LEN) - outpacket -> raw -> file [mainbufix++] - = DHO_PAD; - } - } - return; -} - -/* Store all the requested options into the requested buffer. */ - -int store_options (buffer, buflen, options, priority_list, priority_len, - first_cutoff, second_cutoff) - unsigned char *buffer; - int buflen; - struct tree_cache **options; - unsigned char *priority_list; - int priority_len; - int first_cutoff, second_cutoff; -{ - int bufix = 0; - int option_stored [256]; - int missed = 0; - int missed_code = 0; - int missed_length = 0; - int result; - int i; - int ix; - - /* 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; - - /* Find the value of the option... */ - if (!tree_evaluate (options [code])) { - continue; - } - - /* We should now have a constant length for the option. */ - length = options [code] -> len; - - /* 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; - 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 (code, data, len) - unsigned char code; - unsigned char *data; - int len; -{ - static char optbuf [32768]; /* XXX */ - int hunksize = 0; - int numhunk = -1; - int numelem = 0; - char fmtbuf [32]; - int i, j; - char *op = optbuf; - unsigned char *dp = data; - struct in_addr foo; - - /* Figure out the size of the data. */ - for (i = 0; dhcp_options [code].format [i]; i++) { - if (!numhunk) { - warn ("%s: Excess information in format string: %s\n", - 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 '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: - warn ("%s: garbage in format string: %s\n", - dhcp_options [code].name, - &(dhcp_options [code].format [i])); - break; - } - } - - /* Check for too few bytes... */ - if (hunksize > len) { - warn ("%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) - warn ("%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) - warn ("%s: %d extra bytes at end of array\n", - 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++) { - switch (fmtbuf [j]) { - case 't': - strcpy (op, dp); - break; - case 'I': - foo.s_addr = htonl (getULong (dp)); - strcpy (op, inet_ntoa (foo)); - dp += 4; - break; - case 'l': - sprintf (op, "%ld", getLong (dp)); - dp += 4; - break; - case 'L': - sprintf (op, "%ld", getULong (dp)); - dp += 4; - break; - case 's': - sprintf (op, "%d", getShort (dp)); - dp += 2; - break; - case 'S': - sprintf (op, "%d", getUShort (dp)); - dp += 2; - break; - case 'b': - sprintf (op, "%d", *(char *)dp++); - break; - case 'B': - sprintf (op, "%d", *dp++); - break; - case 'f': - strcpy (op, *dp++ ? "true" : "false"); - break; - default: - warn ("Unexpected format code %c", fmtbuf [j]); - } - op += strlen (op); - *op++ = ' '; - } - } - *--op = 0; - return optbuf; -} - - - |