[deliverable/linux.git] / net / dccp / options.c

/*
 *  net/dccp/options.c
 *
 *  An implementation of the DCCP protocol
 *  Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
 *  Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
 *  Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz>
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */
#include <linux/config.h>
#include <linux/dccp.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>

#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"

/* stores the default values for new connection. may be changed with sysctl */
static const struct dccp_options dccpo_default_values = {
	.dccpo_sequence_window	  = DCCPF_INITIAL_SEQUENCE_WINDOW,
	.dccpo_rx_ccid		  = DCCPF_INITIAL_CCID,
	.dccpo_tx_ccid		  = DCCPF_INITIAL_CCID,
	.dccpo_send_ack_vector	  = DCCPF_INITIAL_SEND_ACK_VECTOR,
	.dccpo_send_ndp_count	  = DCCPF_INITIAL_SEND_NDP_COUNT,
};

void dccp_options_init(struct dccp_options *dccpo)
{
	memcpy(dccpo, &dccpo_default_values, sizeof(*dccpo));
}

static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
{
	u32 value = 0;

	if (len > 3)
		value += *bf++ << 24;
	if (len > 2)
		value += *bf++ << 16;
	if (len > 1)
		value += *bf++ << 8;
	if (len > 0)
		value += *bf;

	return value;
}

int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
{
	struct dccp_sock *dp = dccp_sk(sk);
#ifdef CONFIG_IP_DCCP_DEBUG
	const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
					"CLIENT rx opt: " : "server rx opt: ";
#endif
	const struct dccp_hdr *dh = dccp_hdr(skb);
	const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
	unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
	unsigned char *opt_ptr = options;
	const unsigned char *opt_end = (unsigned char *)dh +
					(dh->dccph_doff * 4);
	struct dccp_options_received *opt_recv = &dp->dccps_options_received;
	unsigned char opt, len;
	unsigned char *value;
	u32 elapsed_time;

	memset(opt_recv, 0, sizeof(*opt_recv));

	while (opt_ptr != opt_end) {
		opt   = *opt_ptr++;
		len   = 0;
		value = NULL;

		/* Check if this isn't a single byte option */
		if (opt > DCCPO_MAX_RESERVED) {
			if (opt_ptr == opt_end)
				goto out_invalid_option;

			len = *opt_ptr++;
			if (len < 3)
				goto out_invalid_option;
			/*
			 * Remove the type and len fields, leaving
			 * just the value size
			 */
			len	-= 2;
			value	= opt_ptr;
			opt_ptr += len;

			if (opt_ptr > opt_end)
				goto out_invalid_option;
		}

		switch (opt) {
		case DCCPO_PADDING:
			break;
		case DCCPO_NDP_COUNT:
			if (len > 3)
				goto out_invalid_option;

			opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
			dccp_pr_debug("%sNDP count=%d\n", debug_prefix,
				      opt_recv->dccpor_ndp);
			break;
		case DCCPO_ACK_VECTOR_0:
		case DCCPO_ACK_VECTOR_1:
			if (pkt_type == DCCP_PKT_DATA)
				continue;

			if (dp->dccps_options.dccpo_send_ack_vector &&
			    dccp_ackvec_parse(sk, skb, opt, value, len))
				goto out_invalid_option;
			break;
		case DCCPO_TIMESTAMP:
			if (len != 4)
				goto out_invalid_option;

			opt_recv->dccpor_timestamp = ntohl(*(u32 *)value);

			dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp;
			dccp_timestamp(sk, &dp->dccps_timestamp_time);

			dccp_pr_debug("%sTIMESTAMP=%u, ackno=%llu\n",
				      debug_prefix, opt_recv->dccpor_timestamp,
				      (unsigned long long)
				      DCCP_SKB_CB(skb)->dccpd_ack_seq);
			break;
		case DCCPO_TIMESTAMP_ECHO:
			if (len != 4 && len != 6 && len != 8)
				goto out_invalid_option;

			opt_recv->dccpor_timestamp_echo = ntohl(*(u32 *)value);

			dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, ackno=%llu, ",
				      debug_prefix,
				      opt_recv->dccpor_timestamp_echo,
				      len + 2,
				      (unsigned long long)
				      DCCP_SKB_CB(skb)->dccpd_ack_seq);


			if (len == 4)
				break;

			if (len == 6)
				elapsed_time = ntohs(*(u16 *)(value + 4));
			else
				elapsed_time = ntohl(*(u32 *)(value + 4));

			/* Give precedence to the biggest ELAPSED_TIME */
			if (elapsed_time > opt_recv->dccpor_elapsed_time)
				opt_recv->dccpor_elapsed_time = elapsed_time;
			break;
		case DCCPO_ELAPSED_TIME:
			if (len != 2 && len != 4)
				goto out_invalid_option;

			if (pkt_type == DCCP_PKT_DATA)
				continue;

			if (len == 2)
				elapsed_time = ntohs(*(u16 *)value);
			else
				elapsed_time = ntohl(*(u32 *)value);

			if (elapsed_time > opt_recv->dccpor_elapsed_time)
				opt_recv->dccpor_elapsed_time = elapsed_time;

			dccp_pr_debug("%sELAPSED_TIME=%d\n", debug_prefix,
				      elapsed_time);
			break;
			/*
			 * From draft-ietf-dccp-spec-11.txt:
			 *
			 *	Option numbers 128 through 191 are for
			 *	options sent from the HC-Sender to the
			 *	HC-Receiver; option numbers 192 through 255
			 *	are for options sent from the HC-Receiver to
			 *	the HC-Sender.
			 */
		case 128 ... 191: {
			const u16 idx = value - options;

			if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk,
						     opt, len, idx,
						     value) != 0)
				goto out_invalid_option;
		}
			break;
		case 192 ... 255: {
			const u16 idx = value - options;

			if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
						     opt, len, idx,
						     value) != 0)
				goto out_invalid_option;
		}
			break;
		default:
			pr_info("DCCP(%p): option %d(len=%d) not "
				"implemented, ignoring\n",
				sk, opt, len);
			break;
	        }
	}

	return 0;

out_invalid_option:
	DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT);
	DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR;
	pr_info("DCCP(%p): invalid option %d, len=%d\n", sk, opt, len);
	return -1;
}

static void dccp_encode_value_var(const u32 value, unsigned char *to,
				  const unsigned int len)
{
	if (len > 3)
		*to++ = (value & 0xFF000000) >> 24;
	if (len > 2)
		*to++ = (value & 0xFF0000) >> 16;
	if (len > 1)
		*to++ = (value & 0xFF00) >> 8;
	if (len > 0)
		*to++ = (value & 0xFF);
}

static inline int dccp_ndp_len(const int ndp)
{
	return likely(ndp <= 0xFF) ? 1 : ndp <= 0xFFFF ? 2 : 3;
}

void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
			const unsigned char option,
			const void *value, const unsigned char len)
{
	unsigned char *to;

	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) {
		LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert "
			       "%d option!\n", option);
		return;
	}

	DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2;

	to    = skb_push(skb, len + 2);
	*to++ = option;
	*to++ = len + 2;

	memcpy(to, value, len);
}

EXPORT_SYMBOL_GPL(dccp_insert_option);

static void dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb)
{
	struct dccp_sock *dp = dccp_sk(sk);
	int ndp = dp->dccps_ndp_count;

	if (dccp_non_data_packet(skb))
		++dp->dccps_ndp_count;
	else
		dp->dccps_ndp_count = 0;

	if (ndp > 0) {
		unsigned char *ptr;
		const int ndp_len = dccp_ndp_len(ndp);
		const int len = ndp_len + 2;

		if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
			return;

		DCCP_SKB_CB(skb)->dccpd_opt_len += len;

		ptr = skb_push(skb, len);
		*ptr++ = DCCPO_NDP_COUNT;
		*ptr++ = len;
		dccp_encode_value_var(ndp, ptr, ndp_len);
	}
}

static inline int dccp_elapsed_time_len(const u32 elapsed_time)
{
	return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
}

void dccp_insert_option_elapsed_time(struct sock *sk,
				     struct sk_buff *skb,
				     u32 elapsed_time)
{
#ifdef CONFIG_IP_DCCP_DEBUG
	struct dccp_sock *dp = dccp_sk(sk);
	const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
					"CLIENT TX opt: " : "server TX opt: ";
#endif
	const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
	const int len = 2 + elapsed_time_len;
	unsigned char *to;

	if (elapsed_time_len == 0)
		return;

	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
		LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to "
					 "insert elapsed time!\n");
		return;
	}

	DCCP_SKB_CB(skb)->dccpd_opt_len += len;

	to    = skb_push(skb, len);
	*to++ = DCCPO_ELAPSED_TIME;
	*to++ = len;

	if (elapsed_time_len == 2) {
		const u16 var16 = htons((u16)elapsed_time);
		memcpy(to, &var16, 2);
	} else {
		const u32 var32 = htonl(elapsed_time);
		memcpy(to, &var32, 4);
	}

	dccp_pr_debug("%sELAPSED_TIME=%u, len=%d, seqno=%llu\n",
		      debug_prefix, elapsed_time,
		      len,
		      (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);
}

EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);

void dccp_timestamp(const struct sock *sk, struct timeval *tv)
{
	const struct dccp_sock *dp = dccp_sk(sk);

	do_gettimeofday(tv);
	tv->tv_sec  -= dp->dccps_epoch.tv_sec;
	tv->tv_usec -= dp->dccps_epoch.tv_usec;

	while (tv->tv_usec < 0) {
		tv->tv_sec--;
		tv->tv_usec += USEC_PER_SEC;
	}
}

EXPORT_SYMBOL_GPL(dccp_timestamp);

void dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
{
	struct timeval tv;
	u32 now;
	
	dccp_timestamp(sk, &tv);
	now = timeval_usecs(&tv) / 10;
	/* yes this will overflow but that is the point as we want a
	 * 10 usec 32 bit timer which mean it wraps every 11.9 hours */

	now = htonl(now);
	dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now));
}

EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);

static void dccp_insert_option_timestamp_echo(struct sock *sk,
					      struct sk_buff *skb)
{
	struct dccp_sock *dp = dccp_sk(sk);
#ifdef CONFIG_IP_DCCP_DEBUG
	const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
					"CLIENT TX opt: " : "server TX opt: ";
#endif
	struct timeval now;
	u32 tstamp_echo;
	u32 elapsed_time;
	int len, elapsed_time_len;
	unsigned char *to;

	dccp_timestamp(sk, &now);
	elapsed_time = timeval_delta(&now, &dp->dccps_timestamp_time) / 10;
	elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
	len = 6 + elapsed_time_len;

	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
		LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert "
					 "timestamp echo!\n");
		return;
	}

	DCCP_SKB_CB(skb)->dccpd_opt_len += len;

	to    = skb_push(skb, len);
	*to++ = DCCPO_TIMESTAMP_ECHO;
	*to++ = len;

	tstamp_echo = htonl(dp->dccps_timestamp_echo);
	memcpy(to, &tstamp_echo, 4);
	to += 4;
	
	if (elapsed_time_len == 2) {
		const u16 var16 = htons((u16)elapsed_time);
		memcpy(to, &var16, 2);
	} else if (elapsed_time_len == 4) {
		const u32 var32 = htonl(elapsed_time);
		memcpy(to, &var32, 4);
	}

	dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, seqno=%llu\n",
		      debug_prefix, dp->dccps_timestamp_echo,
		      len,
		      (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);

	dp->dccps_timestamp_echo = 0;
	dp->dccps_timestamp_time.tv_sec = 0;
	dp->dccps_timestamp_time.tv_usec = 0;
}

void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
{
	struct dccp_sock *dp = dccp_sk(sk);

	DCCP_SKB_CB(skb)->dccpd_opt_len = 0;

	if (dp->dccps_options.dccpo_send_ndp_count)
		dccp_insert_option_ndp(sk, skb);

	if (!dccp_packet_without_ack(skb)) {
		if (dp->dccps_options.dccpo_send_ack_vector &&
		    dccp_ackvec_pending(dp->dccps_hc_rx_ackvec))
			dccp_insert_option_ackvec(sk, skb);
		if (dp->dccps_timestamp_echo != 0)
			dccp_insert_option_timestamp_echo(sk, skb);
	}

	if (dp->dccps_hc_rx_insert_options) {
		ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb);
		dp->dccps_hc_rx_insert_options = 0;
	}
	if (dp->dccps_hc_tx_insert_options) {
		ccid_hc_tx_insert_options(dp->dccps_hc_tx_ccid, sk, skb);
		dp->dccps_hc_tx_insert_options = 0;
	}

	/* XXX: insert other options when appropriate */

	if (DCCP_SKB_CB(skb)->dccpd_opt_len != 0) {
		/* The length of all options has to be a multiple of 4 */
		int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;

		if (padding != 0) {
			padding = 4 - padding;
			memset(skb_push(skb, padding), 0, padding);
			DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
		}
	}
}
Commit	Line	Data
7c657876 ACM	1	/*
	2	* net/dccp/options.c
	3	*
	4	* An implementation of the DCCP protocol
1bc09869 IM	5	* Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
	6	* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
	7	* Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz>
7c657876 ACM	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License
	11	* as published by the Free Software Foundation; either version
	12	* 2 of the License, or (at your option) any later version.
	13	*/
	14	#include <linux/config.h>
	15	#include <linux/dccp.h>
	16	#include <linux/module.h>
	17	#include <linux/types.h>
	18	#include <linux/kernel.h>
	19	#include <linux/skbuff.h>
	20
ae31c339	21	#include "ackvec.h"
7c657876 ACM	22	#include "ccid.h"
	23	#include "dccp.h"
	24
7c657876 ACM	25	/* stores the default values for new connection. may be changed with sysctl */
	26	static const struct dccp_options dccpo_default_values = {
	27	.dccpo_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW,
561713cf ACM	28	.dccpo_rx_ccid = DCCPF_INITIAL_CCID,
561713cf ACM	29	.dccpo_tx_ccid = DCCPF_INITIAL_CCID,
7c657876 ACM	30	.dccpo_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR,
	31	.dccpo_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT,
	32	};
	33
	34	void dccp_options_init(struct dccp_options *dccpo)
	35	{
	36	memcpy(dccpo, &dccpo_default_values, sizeof(*dccpo));
	37	}
	38
	39	static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
	40	{
	41	u32 value = 0;
	42
	43	if (len > 3)
	44	value += *bf++ << 24;
	45	if (len > 2)
	46	value += *bf++ << 16;
	47	if (len > 1)
	48	value += *bf++ << 8;
	49	if (len > 0)
	50	value += *bf;
	51
	52	return value;
	53	}
	54
	55	int dccp_parse_options(struct sock sk, struct sk_buff skb)
	56	{
	57	struct dccp_sock *dp = dccp_sk(sk);
725ba8ee	58	#ifdef CONFIG_IP_DCCP_DEBUG
7690af3f ACM	59	const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
7690af3f ACM	60	"CLIENT rx opt: " : "server rx opt: ";
7c657876 ACM	61	#endif
	62	const struct dccp_hdr *dh = dccp_hdr(skb);
	63	const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
	64	unsigned char options = (unsigned char )dh + dccp_hdr_len(skb);
	65	unsigned char *opt_ptr = options;
7690af3f ACM	66	const unsigned char opt_end = (unsigned char )dh +
7690af3f ACM	67	(dh->dccph_doff * 4);
7c657876 ACM	68	struct dccp_options_received *opt_recv = &dp->dccps_options_received;
	69	unsigned char opt, len;
	70	unsigned char *value;
1c14ac0a	71	u32 elapsed_time;
7c657876 ACM	72
	73	memset(opt_recv, 0, sizeof(*opt_recv));
	74
	75	while (opt_ptr != opt_end) {
	76	opt = *opt_ptr++;
	77	len = 0;
	78	value = NULL;
	79
	80	/* Check if this isn't a single byte option */
	81	if (opt > DCCPO_MAX_RESERVED) {
	82	if (opt_ptr == opt_end)
	83	goto out_invalid_option;
	84
	85	len = *opt_ptr++;
	86	if (len < 3)
	87	goto out_invalid_option;
	88	/*
	89	* Remove the type and len fields, leaving
	90	* just the value size
	91	*/
	92	len -= 2;
	93	value = opt_ptr;
	94	opt_ptr += len;
	95
	96	if (opt_ptr > opt_end)
	97	goto out_invalid_option;
	98	}
	99
	100	switch (opt) {
	101	case DCCPO_PADDING:
	102	break;
	103	case DCCPO_NDP_COUNT:
	104	if (len > 3)
	105	goto out_invalid_option;
	106
	107	opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
7690af3f ACM	108	dccp_pr_debug("%sNDP count=%d\n", debug_prefix,
7690af3f ACM	109	opt_recv->dccpor_ndp);
7c657876 ACM	110	break;
7c657876 ACM	111	case DCCPO_ACK_VECTOR_0:
ae31c339	112	case DCCPO_ACK_VECTOR_1:
7c657876 ACM	113	if (pkt_type == DCCP_PKT_DATA)
	114	continue;
	115
ae31c339 ACM	116	if (dp->dccps_options.dccpo_send_ack_vector &&
	117	dccp_ackvec_parse(sk, skb, opt, value, len))
	118	goto out_invalid_option;
7c657876 ACM	119	break;
	120	case DCCPO_TIMESTAMP:
	121	if (len != 4)
	122	goto out_invalid_option;
	123
	124	opt_recv->dccpor_timestamp = ntohl((u32 )value);
	125
	126	dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp;
b0e56780	127	dccp_timestamp(sk, &dp->dccps_timestamp_time);
7c657876 ACM	128
	129	dccp_pr_debug("%sTIMESTAMP=%u, ackno=%llu\n",
	130	debug_prefix, opt_recv->dccpor_timestamp,
f6ccf554	131	(unsigned long long)
7c657876 ACM	132	DCCP_SKB_CB(skb)->dccpd_ack_seq);
	133	break;
	134	case DCCPO_TIMESTAMP_ECHO:
1bc09869	135	if (len != 4 && len != 6 && len != 8)
7c657876 ACM	136	goto out_invalid_option;
	137
	138	opt_recv->dccpor_timestamp_echo = ntohl((u32 )value);
	139
1bc09869	140	dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, ackno=%llu, ",
7690af3f ACM	141	debug_prefix,
7690af3f ACM	142	opt_recv->dccpor_timestamp_echo,
f6ccf554 DM	143	len + 2,
f6ccf554 DM	144	(unsigned long long)
1bc09869 IM	145	DCCP_SKB_CB(skb)->dccpd_ack_seq);
1bc09869 IM	146
1bc09869	147
1c14ac0a ACM	148	if (len == 4)
	149	break;
	150
	151	if (len == 6)
	152	elapsed_time = ntohs((u16 )(value + 4));
	153	else
	154	elapsed_time = ntohl((u32 )(value + 4));
	155
	156	/* Give precedence to the biggest ELAPSED_TIME */
	157	if (elapsed_time > opt_recv->dccpor_elapsed_time)
	158	opt_recv->dccpor_elapsed_time = elapsed_time;
7c657876 ACM	159	break;
7c657876 ACM	160	case DCCPO_ELAPSED_TIME:
1bc09869	161	if (len != 2 && len != 4)
7c657876 ACM	162	goto out_invalid_option;
	163
	164	if (pkt_type == DCCP_PKT_DATA)
	165	continue;
1bc09869 IM	166
1bc09869 IM	167	if (len == 2)
1c14ac0a	168	elapsed_time = ntohs((u16 )value);
1bc09869	169	else
1c14ac0a ACM	170	elapsed_time = ntohl((u32 )value);
	171
	172	if (elapsed_time > opt_recv->dccpor_elapsed_time)
	173	opt_recv->dccpor_elapsed_time = elapsed_time;
1bc09869	174
7c657876	175	dccp_pr_debug("%sELAPSED_TIME=%d\n", debug_prefix,
1c14ac0a	176	elapsed_time);
7c657876 ACM	177	break;
	178	/*
	179	* From draft-ietf-dccp-spec-11.txt:
	180	*
7690af3f ACM	181	* Option numbers 128 through 191 are for
	182	* options sent from the HC-Sender to the
	183	* HC-Receiver; option numbers 192 through 255
	184	* are for options sent from the HC-Receiver to
	185	* the HC-Sender.
7c657876 ACM	186	*/
	187	case 128 ... 191: {
	188	const u16 idx = value - options;
	189
7690af3f ACM	190	if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk,
	191	opt, len, idx,
	192	value) != 0)
7c657876 ACM	193	goto out_invalid_option;
	194	}
	195	break;
	196	case 192 ... 255: {
	197	const u16 idx = value - options;
	198
7690af3f ACM	199	if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
	200	opt, len, idx,
	201	value) != 0)
7c657876 ACM	202	goto out_invalid_option;
	203	}
	204	break;
	205	default:
7690af3f ACM	206	pr_info("DCCP(%p): option %d(len=%d) not "
7690af3f ACM	207	"implemented, ignoring\n",
7c657876 ACM	208	sk, opt, len);
	209	break;
	210	}
	211	}
	212
	213	return 0;
	214
	215	out_invalid_option:
	216	DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT);
	217	DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR;
	218	pr_info("DCCP(%p): invalid option %d, len=%d\n", sk, opt, len);
	219	return -1;
	220	}
	221
	222	static void dccp_encode_value_var(const u32 value, unsigned char *to,
	223	const unsigned int len)
	224	{
	225	if (len > 3)
	226	*to++ = (value & 0xFF000000) >> 24;
	227	if (len > 2)
	228	*to++ = (value & 0xFF0000) >> 16;
	229	if (len > 1)
	230	*to++ = (value & 0xFF00) >> 8;
	231	if (len > 0)
	232	*to++ = (value & 0xFF);
	233	}
	234
	235	static inline int dccp_ndp_len(const int ndp)
	236	{
	237	return likely(ndp <= 0xFF) ? 1 : ndp <= 0xFFFF ? 2 : 3;
	238	}
	239
	240	void dccp_insert_option(struct sock sk, struct sk_buff skb,
	241	const unsigned char option,
	242	const void *value, const unsigned char len)
	243	{
	244	unsigned char *to;
	245
	246	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) {
7690af3f ACM	247	LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert "
7690af3f ACM	248	"%d option!\n", option);
7c657876 ACM	249	return;
	250	}
	251
	252	DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2;
	253
	254	to = skb_push(skb, len + 2);
	255	*to++ = option;
	256	*to++ = len + 2;
	257
	258	memcpy(to, value, len);
	259	}
	260
	261	EXPORT_SYMBOL_GPL(dccp_insert_option);
	262
	263	static void dccp_insert_option_ndp(struct sock sk, struct sk_buff skb)
	264	{
	265	struct dccp_sock *dp = dccp_sk(sk);
	266	int ndp = dp->dccps_ndp_count;
	267
	268	if (dccp_non_data_packet(skb))
	269	++dp->dccps_ndp_count;
	270	else
	271	dp->dccps_ndp_count = 0;
	272
	273	if (ndp > 0) {
	274	unsigned char *ptr;
	275	const int ndp_len = dccp_ndp_len(ndp);
	276	const int len = ndp_len + 2;
	277
	278	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
	279	return;
	280
	281	DCCP_SKB_CB(skb)->dccpd_opt_len += len;
	282
	283	ptr = skb_push(skb, len);
	284	*ptr++ = DCCPO_NDP_COUNT;
	285	*ptr++ = len;
	286	dccp_encode_value_var(ndp, ptr, ndp_len);
	287	}
	288	}
	289
	290	static inline int dccp_elapsed_time_len(const u32 elapsed_time)
	291	{
b1c9fe7b	292	return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
7c657876 ACM	293	}
	294
	295	void dccp_insert_option_elapsed_time(struct sock *sk,
	296	struct sk_buff *skb,
	297	u32 elapsed_time)
	298	{
725ba8ee	299	#ifdef CONFIG_IP_DCCP_DEBUG
7c657876	300	struct dccp_sock *dp = dccp_sk(sk);
7690af3f ACM	301	const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
7690af3f ACM	302	"CLIENT TX opt: " : "server TX opt: ";
7c657876 ACM	303	#endif
	304	const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
	305	const int len = 2 + elapsed_time_len;
	306	unsigned char *to;
	307
1bc09869	308	if (elapsed_time_len == 0)
7c657876 ACM	309	return;
	310
	311	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
7690af3f ACM	312	LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to "
7690af3f ACM	313	"insert elapsed time!\n");
7c657876 ACM	314	return;
	315	}
	316
	317	DCCP_SKB_CB(skb)->dccpd_opt_len += len;
	318
	319	to = skb_push(skb, len);
	320	*to++ = DCCPO_ELAPSED_TIME;
	321	*to++ = len;
	322
1bc09869 IM	323	if (elapsed_time_len == 2) {
	324	const u16 var16 = htons((u16)elapsed_time);
	325	memcpy(to, &var16, 2);
	326	} else {
	327	const u32 var32 = htonl(elapsed_time);
	328	memcpy(to, &var32, 4);
	329	}
7c657876 ACM	330
	331	dccp_pr_debug("%sELAPSED_TIME=%u, len=%d, seqno=%llu\n",
	332	debug_prefix, elapsed_time,
f6ccf554 DM	333	len,
f6ccf554 DM	334	(unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);
7c657876 ACM	335	}
7c657876 ACM	336
d4b81ff7	337	EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);
7c657876	338
b0e56780 ACM	339	void dccp_timestamp(const struct sock sk, struct timeval tv)
	340	{
	341	const struct dccp_sock *dp = dccp_sk(sk);
	342
	343	do_gettimeofday(tv);
	344	tv->tv_sec -= dp->dccps_epoch.tv_sec;
	345	tv->tv_usec -= dp->dccps_epoch.tv_usec;
	346
	347	while (tv->tv_usec < 0) {
	348	tv->tv_sec--;
	349	tv->tv_usec += USEC_PER_SEC;
	350	}
	351	}
	352
	353	EXPORT_SYMBOL_GPL(dccp_timestamp);
	354
d4b81ff7	355	void dccp_insert_option_timestamp(struct sock sk, struct sk_buff skb)
7c657876	356	{
1bc09869 IM	357	struct timeval tv;
	358	u32 now;
	359
b0e56780 ACM	360	dccp_timestamp(sk, &tv);
b0e56780 ACM	361	now = timeval_usecs(&tv) / 10;
1bc09869 IM	362	/* yes this will overflow but that is the point as we want a
	363	* 10 usec 32 bit timer which mean it wraps every 11.9 hours */
	364
	365	now = htonl(now);
7c657876 ACM	366	dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now));
	367	}
	368
d4b81ff7 ACM	369	EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);
d4b81ff7 ACM	370
7690af3f ACM	371	static void dccp_insert_option_timestamp_echo(struct sock *sk,
7690af3f ACM	372	struct sk_buff *skb)
7c657876 ACM	373	{
7c657876 ACM	374	struct dccp_sock *dp = dccp_sk(sk);
725ba8ee	375	#ifdef CONFIG_IP_DCCP_DEBUG
7690af3f ACM	376	const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
7690af3f ACM	377	"CLIENT TX opt: " : "server TX opt: ";
7c657876	378	#endif
b0e56780	379	struct timeval now;
7c657876	380	u32 tstamp_echo;
b0e56780 ACM	381	u32 elapsed_time;
b0e56780 ACM	382	int len, elapsed_time_len;
7c657876 ACM	383	unsigned char *to;
7c657876 ACM	384
b0e56780 ACM	385	dccp_timestamp(sk, &now);
	386	elapsed_time = timeval_delta(&now, &dp->dccps_timestamp_time) / 10;
	387	elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
	388	len = 6 + elapsed_time_len;
	389
7c657876	390	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
7690af3f ACM	391	LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert "
7690af3f ACM	392	"timestamp echo!\n");
7c657876 ACM	393	return;
	394	}
	395
	396	DCCP_SKB_CB(skb)->dccpd_opt_len += len;
	397
	398	to = skb_push(skb, len);
	399	*to++ = DCCPO_TIMESTAMP_ECHO;
	400	*to++ = len;
	401
	402	tstamp_echo = htonl(dp->dccps_timestamp_echo);
	403	memcpy(to, &tstamp_echo, 4);
	404	to += 4;
1bc09869 IM	405
	406	if (elapsed_time_len == 2) {
	407	const u16 var16 = htons((u16)elapsed_time);
	408	memcpy(to, &var16, 2);
	409	} else if (elapsed_time_len == 4) {
	410	const u32 var32 = htonl(elapsed_time);
	411	memcpy(to, &var32, 4);
	412	}
7c657876 ACM	413
	414	dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, seqno=%llu\n",
	415	debug_prefix, dp->dccps_timestamp_echo,
f6ccf554 DM	416	len,
f6ccf554 DM	417	(unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);
7c657876 ACM	418
7c657876 ACM	419	dp->dccps_timestamp_echo = 0;
1bc09869 IM	420	dp->dccps_timestamp_time.tv_sec = 0;
1bc09869 IM	421	dp->dccps_timestamp_time.tv_usec = 0;
7c657876 ACM	422	}
	423
	424	void dccp_insert_options(struct sock sk, struct sk_buff skb)
	425	{
	426	struct dccp_sock *dp = dccp_sk(sk);
	427
	428	DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
	429
	430	if (dp->dccps_options.dccpo_send_ndp_count)
	431	dccp_insert_option_ndp(sk, skb);
	432
	433	if (!dccp_packet_without_ack(skb)) {
	434	if (dp->dccps_options.dccpo_send_ack_vector &&
ae31c339 ACM	435	dccp_ackvec_pending(dp->dccps_hc_rx_ackvec))
ae31c339 ACM	436	dccp_insert_option_ackvec(sk, skb);
7c657876 ACM	437	if (dp->dccps_timestamp_echo != 0)
	438	dccp_insert_option_timestamp_echo(sk, skb);
	439	}
	440
507d37cf ACM	441	if (dp->dccps_hc_rx_insert_options) {
	442	ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb);
	443	dp->dccps_hc_rx_insert_options = 0;
	444	}
	445	if (dp->dccps_hc_tx_insert_options) {
	446	ccid_hc_tx_insert_options(dp->dccps_hc_tx_ccid, sk, skb);
	447	dp->dccps_hc_tx_insert_options = 0;
	448	}
7c657876 ACM	449
	450	/* XXX: insert other options when appropriate */
	451
	452	if (DCCP_SKB_CB(skb)->dccpd_opt_len != 0) {
	453	/* The length of all options has to be a multiple of 4 */
	454	int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
	455
	456	if (padding != 0) {
	457	padding = 4 - padding;
	458	memset(skb_push(skb, padding), 0, padding);
	459	DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
	460	}
	461	}
	462	}