1 /*	$OpenBSD: options.c,v 1.35 2017/02/13 22:33:39 krw Exp $	*/
3 /* DHCP options parsing and reassembly. */
72  * Parse all available options out of the specified packet.
78 	memset(packet->options, 0, sizeof(packet->options));  in parse_options()
81 	if (memcmp(packet->raw->options, DHCP_OPTIONS_COOKIE, 4)) {  in parse_options()
87 	 * Go through the options field, up to the end of the packet or  in parse_options()
90 	parse_option_buffer(packet, &packet->raw->options[4],  in parse_options()
95 	 * options out of the buffer(s) containing them.  in parse_options()
98 	    packet->options[DHO_DHCP_OPTION_OVERLOAD].data) {  in parse_options()
99 		if (packet->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 1)  in parse_options()
103 		if (packet->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 2)  in parse_options()
111  * Parse options out of the specified buffer, storing addresses of
112  * option values in packet->options and setting packet->options_valid if
127 		/* Pad options don't have a length - just skip them. */  in parse_option_buffer()
160 				log_warnx("Many bogus options seen in "  in parse_option_buffer()
164 				log_warnx("options - hope for the best!");  in parse_option_buffer()
175 		if (!packet->options[code].data) {  in parse_option_buffer()
186 			packet->options[code].len = len;  in parse_option_buffer()
187 			packet->options[code].data = t;  in parse_option_buffer()
194 			t = calloc(1, len + packet->options[code].len + 1);  in parse_option_buffer()
198 			memcpy(t, packet->options[code].data,  in parse_option_buffer()
199 				packet->options[code].len);  in parse_option_buffer()
200 			memcpy(t + packet->options[code].len,  in parse_option_buffer()
202 			packet->options[code].len += len;  in parse_option_buffer()
203 			t[packet->options[code].len] = 0;  in parse_option_buffer()
204 			free(packet->options[code].data);  in parse_option_buffer()
205 			packet->options[code].data = t;  in parse_option_buffer()
213  * Fill priority_list with a complete list of DHCP options sorted by
215  *     1) Mandatory options.
216  *     2) Options from prl that are not already present.
217  *     3) Options from the default list that are not already present.
229 	/* Some options we don't want on the priority list. */  in create_priority_list()
233 	/* Mandatory options. */  in create_priority_list()
268  * cons options into a big buffer, and then split them out into the
270  * vendor options using the same routine.
274     int mms, struct tree_cache **options,  in cons_options()  argument
292 	    inpacket->options[DHO_DHCP_MAX_MESSAGE_SIZE].data &&  in cons_options()
293 	    (inpacket->options[DHO_DHCP_MAX_MESSAGE_SIZE].len >=  in cons_options()
296 		    inpacket->options[DHO_DHCP_MAX_MESSAGE_SIZE].data);  in cons_options()
308 	if (main_buffer_size > sizeof(outpacket->options))  in cons_options()
309 		main_buffer_size = sizeof(outpacket->options);  in cons_options()
315 	memset(outpacket->options, DHO_PAD, sizeof(outpacket->options));  in cons_options()
324 	 * Get complete list of possible options in priority order. Use the  in cons_options()
325 	 * list provided in the options. Lacking that use the list provided by  in cons_options()
330 	    inpacket->options[DHO_DHCP_PARAMETER_REQUEST_LIST].data)  in cons_options()
332 		    inpacket->options[DHO_DHCP_PARAMETER_REQUEST_LIST].data,  in cons_options()
333 		    inpacket->options[DHO_DHCP_PARAMETER_REQUEST_LIST].len);  in cons_options()
340 	 * Copy the options into the big buffer, including leading cookie and  in cons_options()
344 	option_size = store_options(buffer, main_buffer_size, options,  in cons_options()
350 	memcpy(&outpacket->options[0], buffer, main_buffer_size);  in cons_options()
393  * Store all the requested options into the requested buffer. Insert the
394  * required cookie, DHO_DHCP_OPTION_OVERLOAD options and append a DHO_END if
399     struct tree_cache **options, unsigned char *priority_list, int overload,  in store_options()  argument
422 	 * Store options in the order they appear in the priority list.  in store_options()
430 		if (!options[code] || !tree_evaluate(options[code]))  in store_options()
439 		 * DHCP server is sending Classless Static Routes options  in store_options()
441 		 * Router or Static Routes options.  in store_options()
448 		length = options[code]->len;  in store_options()
456 			    options[code]->value + ix);  in store_options()
496 		/* Didn't manage to store any options. */  in store_options()
502 	/* Fill in overload option value based on space used for options. */  in store_options()
518 			 * choke on DHO_PAD options there.  in store_options()
551 	    tp.options[DHO_DHCP_MESSAGE_TYPE].data)  in do_packet()
552 		tp.packet_type = tp.options[DHO_DHCP_MESSAGE_TYPE].data[0];  in do_packet()
559 	/* Free the data associated with the options. */  in do_packet()
561 		free(tp.options[i].data);  in do_packet()