[linux-block.git] / net / dccp / options.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  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 <ian.mcdonald@jandi.co.nz>
 */
#include <linux/dccp.h>
#include <linux/module.h>
#include <linux/types.h>
#include <asm/unaligned.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>

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

u64 dccp_decode_value_var(const u8 *bf, const u8 len)
{
	u64 value = 0;

	if (len >= DCCP_OPTVAL_MAXLEN)
		value += ((u64)*bf++) << 40;
	if (len > 4)
		value += ((u64)*bf++) << 32;
	if (len > 3)
		value += ((u64)*bf++) << 24;
	if (len > 2)
		value += ((u64)*bf++) << 16;
	if (len > 1)
		value += ((u64)*bf++) << 8;
	if (len > 0)
		value += *bf;

	return value;
}

/**
 * dccp_parse_options  -  Parse DCCP options present in @skb
 * @sk: client|server|listening dccp socket (when @dreq != NULL)
 * @dreq: request socket to use during connection setup, or NULL
 */
int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
		       struct sk_buff *skb)
{
	struct dccp_sock *dp = dccp_sk(sk);
	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 *uninitialized_var(value);
	u32 elapsed_time;
	__be32 opt_val;
	int rc;
	int mandatory = 0;

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

	opt = len = 0;
	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_nonsensical_length;

			len = *opt_ptr++;
			if (len < 2)
				goto out_nonsensical_length;
			/*
			 * 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_nonsensical_length;
		}

		/*
		 * CCID-specific options are ignored during connection setup, as
		 * negotiation may still be in progress (see RFC 4340, 10.3).
		 * The same applies to Ack Vectors, as these depend on the CCID.
		 */
		if (dreq != NULL && (opt >= DCCPO_MIN_RX_CCID_SPECIFIC ||
		    opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1))
			goto ignore_option;

		switch (opt) {
		case DCCPO_PADDING:
			break;
		case DCCPO_MANDATORY:
			if (mandatory)
				goto out_invalid_option;
			if (pkt_type != DCCP_PKT_DATA)
				mandatory = 1;
			break;
		case DCCPO_NDP_COUNT:
			if (len > 6)
				goto out_invalid_option;

			opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
			dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk),
				      (unsigned long long)opt_recv->dccpor_ndp);
			break;
		case DCCPO_CHANGE_L ... DCCPO_CONFIRM_R:
			if (pkt_type == DCCP_PKT_DATA)      /* RFC 4340, 6 */
				break;
			if (len == 0)
				goto out_invalid_option;
			rc = dccp_feat_parse_options(sk, dreq, mandatory, opt,
						    *value, value + 1, len - 1);
			if (rc)
				goto out_featneg_failed;
			break;
		case DCCPO_TIMESTAMP:
			if (len != 4)
				goto out_invalid_option;
			/*
			 * RFC 4340 13.1: "The precise time corresponding to
			 * Timestamp Value zero is not specified". We use
			 * zero to indicate absence of a meaningful timestamp.
			 */
			opt_val = get_unaligned((__be32 *)value);
			if (unlikely(opt_val == 0)) {
				DCCP_WARN("Timestamp with zero value\n");
				break;
			}

			if (dreq != NULL) {
				dreq->dreq_timestamp_echo = ntohl(opt_val);
				dreq->dreq_timestamp_time = dccp_timestamp();
			} else {
				opt_recv->dccpor_timestamp =
					dp->dccps_timestamp_echo = ntohl(opt_val);
				dp->dccps_timestamp_time = dccp_timestamp();
			}
			dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n",
				      dccp_role(sk), ntohl(opt_val),
				      (unsigned long long)
				      DCCP_SKB_CB(skb)->dccpd_ack_seq);
			/* schedule an Ack in case this sender is quiescent */
			inet_csk_schedule_ack(sk);
			break;
		case DCCPO_TIMESTAMP_ECHO:
			if (len != 4 && len != 6 && len != 8)
				goto out_invalid_option;

			opt_val = get_unaligned((__be32 *)value);
			opt_recv->dccpor_timestamp_echo = ntohl(opt_val);

			dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, "
				      "ackno=%llu", dccp_role(sk),
				      opt_recv->dccpor_timestamp_echo,
				      len + 2,
				      (unsigned long long)
				      DCCP_SKB_CB(skb)->dccpd_ack_seq);

			value += 4;

			if (len == 4) {		/* no elapsed time included */
				dccp_pr_debug_cat("\n");
				break;
			}

			if (len == 6) {		/* 2-byte elapsed time */
				__be16 opt_val2 = get_unaligned((__be16 *)value);
				elapsed_time = ntohs(opt_val2);
			} else {		/* 4-byte elapsed time */
				opt_val = get_unaligned((__be32 *)value);
				elapsed_time = ntohl(opt_val);
			}

			dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time);

			/* 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 (dccp_packet_without_ack(skb))   /* RFC 4340, 13.2 */
				break;

			if (len == 2) {
				__be16 opt_val2 = get_unaligned((__be16 *)value);
				elapsed_time = ntohs(opt_val2);
			} else if (len == 4) {
				opt_val = get_unaligned((__be32 *)value);
				elapsed_time = ntohl(opt_val);
			} else {
				goto out_invalid_option;
			}

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

			dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
				      dccp_role(sk), elapsed_time);
			break;
		case DCCPO_MIN_RX_CCID_SPECIFIC ... DCCPO_MAX_RX_CCID_SPECIFIC:
			if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk,
						     pkt_type, opt, value, len))
				goto out_invalid_option;
			break;
		case DCCPO_ACK_VECTOR_0:
		case DCCPO_ACK_VECTOR_1:
			if (dccp_packet_without_ack(skb))   /* RFC 4340, 11.4 */
				break;
			/*
			 * Ack vectors are processed by the TX CCID if it is
			 * interested. The RX CCID need not parse Ack Vectors,
			 * since it is only interested in clearing old state.
			 */
			/* fall through */
		case DCCPO_MIN_TX_CCID_SPECIFIC ... DCCPO_MAX_TX_CCID_SPECIFIC:
			if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
						     pkt_type, opt, value, len))
				goto out_invalid_option;
			break;
		default:
			DCCP_CRIT("DCCP(%p): option %d(len=%d) not "
				  "implemented, ignoring", sk, opt, len);
			break;
		}
ignore_option:
		if (opt != DCCPO_MANDATORY)
			mandatory = 0;
	}

	/* mandatory was the last byte in option list -> reset connection */
	if (mandatory)
		goto out_invalid_option;

out_nonsensical_length:
	/* RFC 4340, 5.8: ignore option and all remaining option space */
	return 0;

out_invalid_option:
	DCCP_INC_STATS(DCCP_MIB_INVALIDOPT);
	rc = DCCP_RESET_CODE_OPTION_ERROR;
out_featneg_failed:
	DCCP_WARN("DCCP(%p): Option %d (len=%d) error=%u\n", sk, opt, len, rc);
	DCCP_SKB_CB(skb)->dccpd_reset_code = rc;
	DCCP_SKB_CB(skb)->dccpd_reset_data[0] = opt;
	DCCP_SKB_CB(skb)->dccpd_reset_data[1] = len > 0 ? value[0] : 0;
	DCCP_SKB_CB(skb)->dccpd_reset_data[2] = len > 1 ? value[1] : 0;
	return -1;
}

EXPORT_SYMBOL_GPL(dccp_parse_options);

void dccp_encode_value_var(const u64 value, u8 *to, const u8 len)
{
	if (len >= DCCP_OPTVAL_MAXLEN)
		*to++ = (value & 0xFF0000000000ull) >> 40;
	if (len > 4)
		*to++ = (value & 0xFF00000000ull) >> 32;
	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 u8 dccp_ndp_len(const u64 ndp)
{
	if (likely(ndp <= 0xFF))
		return 1;
	return likely(ndp <= USHRT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6);
}

int dccp_insert_option(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)
		return -1;

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

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

	memcpy(to, value, len);
	return 0;
}

EXPORT_SYMBOL_GPL(dccp_insert_option);

static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb)
{
	struct dccp_sock *dp = dccp_sk(sk);
	u64 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 -1;

		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);
	}

	return 0;
}

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

static int dccp_insert_option_timestamp(struct sk_buff *skb)
{
	__be32 now = htonl(dccp_timestamp());
	/* 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 */

	return dccp_insert_option(skb, DCCPO_TIMESTAMP, &now, sizeof(now));
}

static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
					     struct dccp_request_sock *dreq,
					     struct sk_buff *skb)
{
	__be32 tstamp_echo;
	unsigned char *to;
	u32 elapsed_time, elapsed_time_len, len;

	if (dreq != NULL) {
		elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time;
		tstamp_echo  = htonl(dreq->dreq_timestamp_echo);
		dreq->dreq_timestamp_echo = 0;
	} else {
		elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time;
		tstamp_echo  = htonl(dp->dccps_timestamp_echo);
		dp->dccps_timestamp_echo = 0;
	}

	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)
		return -1;

	DCCP_SKB_CB(skb)->dccpd_opt_len += len;

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

	memcpy(to, &tstamp_echo, 4);
	to += 4;

	if (elapsed_time_len == 2) {
		const __be16 var16 = htons((u16)elapsed_time);
		memcpy(to, &var16, 2);
	} else if (elapsed_time_len == 4) {
		const __be32 var32 = htonl(elapsed_time);
		memcpy(to, &var32, 4);
	}

	return 0;
}

static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
{
	struct dccp_sock *dp = dccp_sk(sk);
	struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
	struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
	const u16 buflen = dccp_ackvec_buflen(av);
	/* Figure out how many options do we need to represent the ackvec */
	const u8 nr_opts = DIV_ROUND_UP(buflen, DCCP_SINGLE_OPT_MAXLEN);
	u16 len = buflen + 2 * nr_opts;
	u8 i, nonce = 0;
	const unsigned char *tail, *from;
	unsigned char *to;

	if (dcb->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
		DCCP_WARN("Lacking space for %u bytes on %s packet\n", len,
			  dccp_packet_name(dcb->dccpd_type));
		return -1;
	}
	/*
	 * Since Ack Vectors are variable-length, we can not always predict
	 * their size. To catch exception cases where the space is running out
	 * on the skb, a separate Sync is scheduled to carry the Ack Vector.
	 */
	if (len > DCCPAV_MIN_OPTLEN &&
	    len + dcb->dccpd_opt_len + skb->len > dp->dccps_mss_cache) {
		DCCP_WARN("No space left for Ack Vector (%u) on skb (%u+%u), "
			  "MPS=%u ==> reduce payload size?\n", len, skb->len,
			  dcb->dccpd_opt_len, dp->dccps_mss_cache);
		dp->dccps_sync_scheduled = 1;
		return 0;
	}
	dcb->dccpd_opt_len += len;

	to   = skb_push(skb, len);
	len  = buflen;
	from = av->av_buf + av->av_buf_head;
	tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;

	for (i = 0; i < nr_opts; ++i) {
		int copylen = len;

		if (len > DCCP_SINGLE_OPT_MAXLEN)
			copylen = DCCP_SINGLE_OPT_MAXLEN;

		/*
		 * RFC 4340, 12.2: Encode the Nonce Echo for this Ack Vector via
		 * its type; ack_nonce is the sum of all individual buf_nonce's.
		 */
		nonce ^= av->av_buf_nonce[i];

		*to++ = DCCPO_ACK_VECTOR_0 + av->av_buf_nonce[i];
		*to++ = copylen + 2;

		/* Check if buf_head wraps */
		if (from + copylen > tail) {
			const u16 tailsize = tail - from;

			memcpy(to, from, tailsize);
			to	+= tailsize;
			len	-= tailsize;
			copylen	-= tailsize;
			from	= av->av_buf;
		}

		memcpy(to, from, copylen);
		from += copylen;
		to   += copylen;
		len  -= copylen;
	}
	/*
	 * Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
	 */
	if (dccp_ackvec_update_records(av, dcb->dccpd_seq, nonce))
		return -ENOBUFS;
	return 0;
}

/**
 * dccp_insert_option_mandatory  -  Mandatory option (5.8.2)
 * Note that since we are using skb_push, this function needs to be called
 * _after_ inserting the option it is supposed to influence (stack order).
 */
int dccp_insert_option_mandatory(struct sk_buff *skb)
{
	if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN)
		return -1;

	DCCP_SKB_CB(skb)->dccpd_opt_len++;
	*(u8 *)skb_push(skb, 1) = DCCPO_MANDATORY;
	return 0;
}

/**
 * dccp_insert_fn_opt  -  Insert single Feature-Negotiation option into @skb
 * @type: %DCCPO_CHANGE_L, %DCCPO_CHANGE_R, %DCCPO_CONFIRM_L, %DCCPO_CONFIRM_R
 * @feat: one out of %dccp_feature_numbers
 * @val: NN value or SP array (preferred element first) to copy
 * @len: true length of @val in bytes (excluding first element repetition)
 * @repeat_first: whether to copy the first element of @val twice
 *
 * The last argument is used to construct Confirm options, where the preferred
 * value and the preference list appear separately (RFC 4340, 6.3.1). Preference
 * lists are kept such that the preferred entry is always first, so we only need
 * to copy twice, and avoid the overhead of cloning into a bigger array.
 */
int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat,
		       u8 *val, u8 len, bool repeat_first)
{
	u8 tot_len, *to;

	/* take the `Feature' field and possible repetition into account */
	if (len > (DCCP_SINGLE_OPT_MAXLEN - 2)) {
		DCCP_WARN("length %u for feature %u too large\n", len, feat);
		return -1;
	}

	if (unlikely(val == NULL || len == 0))
		len = repeat_first = false;
	tot_len = 3 + repeat_first + len;

	if (DCCP_SKB_CB(skb)->dccpd_opt_len + tot_len > DCCP_MAX_OPT_LEN) {
		DCCP_WARN("packet too small for feature %d option!\n", feat);
		return -1;
	}
	DCCP_SKB_CB(skb)->dccpd_opt_len += tot_len;

	to    = skb_push(skb, tot_len);
	*to++ = type;
	*to++ = tot_len;
	*to++ = feat;

	if (repeat_first)
		*to++ = *val;
	if (len)
		memcpy(to, val, len);
	return 0;
}

/* The length of all options needs to be a multiple of 4 (5.8) */
static void dccp_insert_option_padding(struct sk_buff *skb)
{
	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;
	}
}

int 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_send_ndp_count && dccp_insert_option_ndp(sk, skb))
		return -1;

	if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) {

		/* Feature Negotiation */
		if (dccp_feat_insert_opts(dp, NULL, skb))
			return -1;

		if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) {
			/*
			 * Obtain RTT sample from Request/Response exchange.
			 * This is currently used for TFRC initialisation.
			 */
			if (dccp_insert_option_timestamp(skb))
				return -1;

		} else if (dccp_ackvec_pending(sk) &&
			   dccp_insert_option_ackvec(sk, skb)) {
				return -1;
		}
	}

	if (dp->dccps_hc_rx_insert_options) {
		if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
			return -1;
		dp->dccps_hc_rx_insert_options = 0;
	}

	if (dp->dccps_timestamp_echo != 0 &&
	    dccp_insert_option_timestamp_echo(dp, NULL, skb))
		return -1;

	dccp_insert_option_padding(skb);
	return 0;
}

int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
{
	DCCP_SKB_CB(skb)->dccpd_opt_len = 0;

	if (dccp_feat_insert_opts(NULL, dreq, skb))
		return -1;

	/* Obtain RTT sample from Response/Ack exchange (used by TFRC). */
	if (dccp_insert_option_timestamp(skb))
		return -1;

	if (dreq->dreq_timestamp_echo != 0 &&
	    dccp_insert_option_timestamp_echo(NULL, dreq, skb))
		return -1;

	dccp_insert_option_padding(skb);
	return 0;
}
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
7c657876 ACM	2	/*
	3	* net/dccp/options.c
	4	*
	5	* An implementation of the DCCP protocol
1bc09869 IM	6	* Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
1bc09869 IM	7	* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
e6bccd35	8	* Copyright (c) 2005 Ian McDonald <ian.mcdonald@jandi.co.nz>
7c657876	9	*/
7c657876 ACM	10	#include <linux/dccp.h>
	11	#include <linux/module.h>
	12	#include <linux/types.h>
76fd1e87	13	#include <asm/unaligned.h>
7c657876 ACM	14	#include <linux/kernel.h>
	15	#include <linux/skbuff.h>
	16
ae31c339	17	#include "ackvec.h"
7c657876 ACM	18	#include "ccid.h"
7c657876 ACM	19	#include "dccp.h"
afe00251	20	#include "feat.h"
7c657876	21
02fa460e	22	u64 dccp_decode_value_var(const u8 *bf, const u8 len)
7c657876	23	{
02fa460e	24	u64 value = 0;
7c657876	25
02fa460e GR	26	if (len >= DCCP_OPTVAL_MAXLEN)
	27	value += ((u64)*bf++) << 40;
	28	if (len > 4)
	29	value += ((u64)*bf++) << 32;
7c657876	30	if (len > 3)
02fa460e	31	value += ((u64)*bf++) << 24;
7c657876	32	if (len > 2)
02fa460e	33	value += ((u64)*bf++) << 16;
7c657876	34	if (len > 1)
02fa460e	35	value += ((u64)*bf++) << 8;
7c657876 ACM	36	if (len > 0)
	37	value += *bf;
	38
	39	return value;
	40	}
	41
8b819412 GR	42	/**
	43	* dccp_parse_options - Parse DCCP options present in @skb
	44	* @sk: client\|server\|listening dccp socket (when @dreq != NULL)
	45	* @dreq: request socket to use during connection setup, or NULL
	46	*/
	47	int dccp_parse_options(struct sock sk, struct dccp_request_sock dreq,
	48	struct sk_buff *skb)
7c657876 ACM	49	{
7c657876 ACM	50	struct dccp_sock *dp = dccp_sk(sk);
7c657876 ACM	51	const struct dccp_hdr *dh = dccp_hdr(skb);
	52	const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
	53	unsigned char options = (unsigned char )dh + dccp_hdr_len(skb);
	54	unsigned char *opt_ptr = options;
7690af3f ACM	55	const unsigned char opt_end = (unsigned char )dh +
7690af3f ACM	56	(dh->dccph_doff * 4);
7c657876 ACM	57	struct dccp_options_received *opt_recv = &dp->dccps_options_received;
7c657876 ACM	58	unsigned char opt, len;
3ed7cc0f	59	unsigned char *uninitialized_var(value);
1c14ac0a	60	u32 elapsed_time;
76fd1e87	61	__be32 opt_val;
afe00251 AB	62	int rc;
afe00251 AB	63	int mandatory = 0;
7c657876 ACM	64
	65	memset(opt_recv, 0, sizeof(*opt_recv));
	66
fb950496	67	opt = len = 0;
7c657876 ACM	68	while (opt_ptr != opt_end) {
	69	opt = *opt_ptr++;
	70	len = 0;
	71	value = NULL;
	72
	73	/* Check if this isn't a single byte option */
	74	if (opt > DCCPO_MAX_RESERVED) {
	75	if (opt_ptr == opt_end)
faf61c33	76	goto out_nonsensical_length;
7c657876 ACM	77
7c657876 ACM	78	len = *opt_ptr++;
faf61c33 GR	79	if (len < 2)
faf61c33 GR	80	goto out_nonsensical_length;
7c657876 ACM	81	/*
	82	* Remove the type and len fields, leaving
	83	* just the value size
	84	*/
	85	len -= 2;
	86	value = opt_ptr;
	87	opt_ptr += len;
	88
	89	if (opt_ptr > opt_end)
faf61c33	90	goto out_nonsensical_length;
7c657876 ACM	91	}
7c657876 ACM	92
8b819412	93	/*
8b819412 GR	94	* CCID-specific options are ignored during connection setup, as
8b819412 GR	95	* negotiation may still be in progress (see RFC 4340, 10.3).
65907a43	96	* The same applies to Ack Vectors, as these depend on the CCID.
8b819412	97	*/
a18213d1	98	if (dreq != NULL && (opt >= DCCPO_MIN_RX_CCID_SPECIFIC \|\|
65907a43	99	opt == DCCPO_ACK_VECTOR_0 \|\| opt == DCCPO_ACK_VECTOR_1))
8b819412 GR	100	goto ignore_option;
8b819412 GR	101
7c657876 ACM	102	switch (opt) {
	103	case DCCPO_PADDING:
	104	break;
afe00251 AB	105	case DCCPO_MANDATORY:
	106	if (mandatory)
	107	goto out_invalid_option;
6df9424a ACM	108	if (pkt_type != DCCP_PKT_DATA)
6df9424a ACM	109	mandatory = 1;
afe00251	110	break;
7c657876	111	case DCCPO_NDP_COUNT:
5b5d0e70	112	if (len > 6)
7c657876 ACM	113	goto out_invalid_option;
	114
	115	opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
5b5d0e70 GR	116	dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk),
5b5d0e70 GR	117	(unsigned long long)opt_recv->dccpor_ndp);
7c657876	118	break;
b1ad0042 GR	119	case DCCPO_CHANGE_L ... DCCPO_CONFIRM_R:
b1ad0042 GR	120	if (pkt_type == DCCP_PKT_DATA) /* RFC 4340, 6 */
cf86314c	121	break;
a2948659 DR	122	if (len == 0)
a2948659 DR	123	goto out_invalid_option;
e77b8363 GR	124	rc = dccp_feat_parse_options(sk, dreq, mandatory, opt,
	125	*value, value + 1, len - 1);
	126	if (rc)
	127	goto out_featneg_failed;
410e27a4	128	break;
7c657876 ACM	129	case DCCPO_TIMESTAMP:
	130	if (len != 4)
	131	goto out_invalid_option;
b4d4f7c7 GR	132	/*
	133	* RFC 4340 13.1: "The precise time corresponding to
	134	* Timestamp Value zero is not specified". We use
	135	* zero to indicate absence of a meaningful timestamp.
	136	*/
76fd1e87	137	opt_val = get_unaligned((__be32 *)value);
b4d4f7c7 GR	138	if (unlikely(opt_val == 0)) {
	139	DCCP_WARN("Timestamp with zero value\n");
	140	break;
	141	}
7c657876	142
b4d4f7c7 GR	143	if (dreq != NULL) {
	144	dreq->dreq_timestamp_echo = ntohl(opt_val);
	145	dreq->dreq_timestamp_time = dccp_timestamp();
	146	} else {
	147	opt_recv->dccpor_timestamp =
	148	dp->dccps_timestamp_echo = ntohl(opt_val);
	149	dp->dccps_timestamp_time = dccp_timestamp();
	150	}
09dbc389	151	dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n",
b4d4f7c7	152	dccp_role(sk), ntohl(opt_val),
f6ccf554	153	(unsigned long long)
7c657876	154	DCCP_SKB_CB(skb)->dccpd_ack_seq);
ecdfbdab GR	155	/* schedule an Ack in case this sender is quiescent */
ecdfbdab GR	156	inet_csk_schedule_ack(sk);
7c657876 ACM	157	break;
7c657876 ACM	158	case DCCPO_TIMESTAMP_ECHO:
1bc09869	159	if (len != 4 && len != 6 && len != 8)
7c657876 ACM	160	goto out_invalid_option;
7c657876 ACM	161
76fd1e87 GR	162	opt_val = get_unaligned((__be32 *)value);
76fd1e87 GR	163	opt_recv->dccpor_timestamp_echo = ntohl(opt_val);
7c657876	164
09dbc389	165	dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, "
f73f7097	166	"ackno=%llu", dccp_role(sk),
7690af3f	167	opt_recv->dccpor_timestamp_echo,
f6ccf554 DM	168	len + 2,
f6ccf554 DM	169	(unsigned long long)
1bc09869 IM	170	DCCP_SKB_CB(skb)->dccpd_ack_seq);
1bc09869 IM	171
76fd1e87	172	value += 4;
1bc09869	173
76fd1e87	174	if (len == 4) { /* no elapsed time included */
f73f7097	175	dccp_pr_debug_cat("\n");
1c14ac0a	176	break;
f73f7097	177	}
1c14ac0a	178
76fd1e87 GR	179	if (len == 6) { /* 2-byte elapsed time */
	180	__be16 opt_val2 = get_unaligned((__be16 *)value);
	181	elapsed_time = ntohs(opt_val2);
	182	} else { /* 4-byte elapsed time */
	183	opt_val = get_unaligned((__be32 *)value);
	184	elapsed_time = ntohl(opt_val);
	185	}
1c14ac0a	186
dcad856f	187	dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time);
f73f7097	188
1c14ac0a ACM	189	/* Give precedence to the biggest ELAPSED_TIME */
	190	if (elapsed_time > opt_recv->dccpor_elapsed_time)
	191	opt_recv->dccpor_elapsed_time = elapsed_time;
7c657876 ACM	192	break;
7c657876 ACM	193	case DCCPO_ELAPSED_TIME:
c86ab2b6 GR	194	if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */
c86ab2b6 GR	195	break;
1bc09869	196
76fd1e87 GR	197	if (len == 2) {
	198	__be16 opt_val2 = get_unaligned((__be16 *)value);
	199	elapsed_time = ntohs(opt_val2);
c86ab2b6	200	} else if (len == 4) {
76fd1e87 GR	201	opt_val = get_unaligned((__be32 *)value);
76fd1e87 GR	202	elapsed_time = ntohl(opt_val);
c86ab2b6 GR	203	} else {
c86ab2b6 GR	204	goto out_invalid_option;
76fd1e87	205	}
1c14ac0a ACM	206
	207	if (elapsed_time > opt_recv->dccpor_elapsed_time)
	208	opt_recv->dccpor_elapsed_time = elapsed_time;
1bc09869	209
09dbc389 GR	210	dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
09dbc389 GR	211	dccp_role(sk), elapsed_time);
7c657876	212	break;
a18213d1	213	case DCCPO_MIN_RX_CCID_SPECIFIC ... DCCPO_MAX_RX_CCID_SPECIFIC:
7690af3f	214	if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk,
4874c131	215	pkt_type, opt, value, len))
7c657876	216	goto out_invalid_option;
7c657876	217	break;
7e87fe84 GR	218	case DCCPO_ACK_VECTOR_0:
	219	case DCCPO_ACK_VECTOR_1:
	220	if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
	221	break;
	222	/*
	223	* Ack vectors are processed by the TX CCID if it is
	224	* interested. The RX CCID need not parse Ack Vectors,
	225	* since it is only interested in clearing old state.
7e87fe84	226	*/
bc28df6e	227	/* fall through */
a18213d1	228	case DCCPO_MIN_TX_CCID_SPECIFIC ... DCCPO_MAX_TX_CCID_SPECIFIC:
7690af3f	229	if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
4874c131	230	pkt_type, opt, value, len))
7c657876	231	goto out_invalid_option;
7c657876 ACM	232	break;
7c657876 ACM	233	default:
59348b19 GR	234	DCCP_CRIT("DCCP(%p): option %d(len=%d) not "
59348b19 GR	235	"implemented, ignoring", sk, opt, len);
7c657876	236	break;
c9eaf173	237	}
8b819412	238	ignore_option:
afe00251 AB	239	if (opt != DCCPO_MANDATORY)
afe00251 AB	240	mandatory = 0;
7c657876 ACM	241	}
7c657876 ACM	242
6df9424a ACM	243	/* mandatory was the last byte in option list -> reset connection */
	244	if (mandatory)
	245	goto out_invalid_option;
	246
faf61c33 GR	247	out_nonsensical_length:
faf61c33 GR	248	/* RFC 4340, 5.8: ignore option and all remaining option space */
7c657876 ACM	249	return 0;
	250
	251	out_invalid_option:
7309f882	252	DCCP_INC_STATS(DCCP_MIB_INVALIDOPT);
e77b8363 GR	253	rc = DCCP_RESET_CODE_OPTION_ERROR;
	254	out_featneg_failed:
	255	DCCP_WARN("DCCP(%p): Option %d (len=%d) error=%u\n", sk, opt, len, rc);
	256	DCCP_SKB_CB(skb)->dccpd_reset_code = rc;
eac7726b GR	257	DCCP_SKB_CB(skb)->dccpd_reset_data[0] = opt;
	258	DCCP_SKB_CB(skb)->dccpd_reset_data[1] = len > 0 ? value[0] : 0;
	259	DCCP_SKB_CB(skb)->dccpd_reset_data[2] = len > 1 ? value[1] : 0;
7c657876 ACM	260	return -1;
	261	}
	262
b61fafc4 ACM	263	EXPORT_SYMBOL_GPL(dccp_parse_options);
b61fafc4 ACM	264
02fa460e	265	void dccp_encode_value_var(const u64 value, u8 *to, const u8 len)
7c657876	266	{
02fa460e GR	267	if (len >= DCCP_OPTVAL_MAXLEN)
	268	*to++ = (value & 0xFF0000000000ull) >> 40;
	269	if (len > 4)
	270	*to++ = (value & 0xFF00000000ull) >> 32;
7c657876 ACM	271	if (len > 3)
	272	*to++ = (value & 0xFF000000) >> 24;
	273	if (len > 2)
	274	*to++ = (value & 0xFF0000) >> 16;
	275	if (len > 1)
	276	*to++ = (value & 0xFF00) >> 8;
	277	if (len > 0)
	278	*to++ = (value & 0xFF);
	279	}
	280
5b5d0e70	281	static inline u8 dccp_ndp_len(const u64 ndp)
7c657876	282	{
5b5d0e70 GR	283	if (likely(ndp <= 0xFF))
5b5d0e70 GR	284	return 1;
4be929be	285	return likely(ndp <= USHRT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6);
7c657876 ACM	286	}
7c657876 ACM	287
a7d13fbf GR	288	int dccp_insert_option(struct sk_buff *skb, const unsigned char option,
a7d13fbf GR	289	const void *value, const unsigned char len)
7c657876 ACM	290	{
	291	unsigned char *to;
	292
2d0817d1 ACM	293	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN)
2d0817d1 ACM	294	return -1;
7c657876 ACM	295
	296	DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2;
	297
	298	to = skb_push(skb, len + 2);
	299	*to++ = option;
	300	*to++ = len + 2;
	301
	302	memcpy(to, value, len);
2d0817d1	303	return 0;
7c657876 ACM	304	}
	305
	306	EXPORT_SYMBOL_GPL(dccp_insert_option);
	307
2d0817d1	308	static int dccp_insert_option_ndp(struct sock sk, struct sk_buff skb)
7c657876 ACM	309	{
7c657876 ACM	310	struct dccp_sock *dp = dccp_sk(sk);
5b5d0e70	311	u64 ndp = dp->dccps_ndp_count;
7c657876 ACM	312
	313	if (dccp_non_data_packet(skb))
	314	++dp->dccps_ndp_count;
	315	else
	316	dp->dccps_ndp_count = 0;
	317
	318	if (ndp > 0) {
	319	unsigned char *ptr;
	320	const int ndp_len = dccp_ndp_len(ndp);
	321	const int len = ndp_len + 2;
	322
	323	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
2d0817d1	324	return -1;
7c657876 ACM	325
	326	DCCP_SKB_CB(skb)->dccpd_opt_len += len;
	327
	328	ptr = skb_push(skb, len);
	329	*ptr++ = DCCPO_NDP_COUNT;
	330	*ptr++ = len;
	331	dccp_encode_value_var(ndp, ptr, ndp_len);
	332	}
2d0817d1 ACM	333
2d0817d1 ACM	334	return 0;
7c657876 ACM	335	}
	336
	337	static inline int dccp_elapsed_time_len(const u32 elapsed_time)
	338	{
b1c9fe7b	339	return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
7c657876 ACM	340	}
7c657876 ACM	341
1f4f0f64	342	static int dccp_insert_option_timestamp(struct sk_buff *skb)
7c657876	343	{
4c70f383	344	__be32 now = htonl(dccp_timestamp());
1bc09869 IM	345	/* yes this will overflow but that is the point as we want a
	346	* 10 usec 32 bit timer which mean it wraps every 11.9 hours */
	347
a7d13fbf	348	return dccp_insert_option(skb, DCCPO_TIMESTAMP, &now, sizeof(now));
7c657876 ACM	349	}
7c657876 ACM	350
b4d4f7c7 GR	351	static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
b4d4f7c7 GR	352	struct dccp_request_sock *dreq,
2d0817d1	353	struct sk_buff *skb)
7c657876	354	{
60fe62e7	355	__be32 tstamp_echo;
7c657876	356	unsigned char *to;
b4d4f7c7 GR	357	u32 elapsed_time, elapsed_time_len, len;
	358
	359	if (dreq != NULL) {
	360	elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time;
	361	tstamp_echo = htonl(dreq->dreq_timestamp_echo);
	362	dreq->dreq_timestamp_echo = 0;
	363	} else {
	364	elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time;
	365	tstamp_echo = htonl(dp->dccps_timestamp_echo);
	366	dp->dccps_timestamp_echo = 0;
	367	}
	368
b0e56780 ACM	369	elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
	370	len = 6 + elapsed_time_len;
	371
2d0817d1 ACM	372	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
2d0817d1 ACM	373	return -1;
7c657876 ACM	374
	375	DCCP_SKB_CB(skb)->dccpd_opt_len += len;
	376
	377	to = skb_push(skb, len);
	378	*to++ = DCCPO_TIMESTAMP_ECHO;
	379	*to++ = len;
	380
7c657876 ACM	381	memcpy(to, &tstamp_echo, 4);
7c657876 ACM	382	to += 4;
afe00251	383
1bc09869	384	if (elapsed_time_len == 2) {
60fe62e7	385	const __be16 var16 = htons((u16)elapsed_time);
1bc09869 IM	386	memcpy(to, &var16, 2);
1bc09869 IM	387	} else if (elapsed_time_len == 4) {
60fe62e7	388	const __be32 var32 = htonl(elapsed_time);
1bc09869 IM	389	memcpy(to, &var32, 4);
1bc09869 IM	390	}
7c657876	391
2d0817d1	392	return 0;
7c657876 ACM	393	}
7c657876 ACM	394
7d870936 GR	395	static int dccp_insert_option_ackvec(struct sock sk, struct sk_buff skb)
	396	{
	397	struct dccp_sock *dp = dccp_sk(sk);
	398	struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
d83447f0	399	struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
b3d14bff	400	const u16 buflen = dccp_ackvec_buflen(av);
7d870936	401	/* Figure out how many options do we need to represent the ackvec */
b3d14bff GR	402	const u8 nr_opts = DIV_ROUND_UP(buflen, DCCP_SINGLE_OPT_MAXLEN);
b3d14bff GR	403	u16 len = buflen + 2 * nr_opts;
7d870936 GR	404	u8 i, nonce = 0;
	405	const unsigned char tail, from;
	406	unsigned char *to;
	407
d83447f0 GR	408	if (dcb->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
	409	DCCP_WARN("Lacking space for %u bytes on %s packet\n", len,
	410	dccp_packet_name(dcb->dccpd_type));
7d870936	411	return -1;
d83447f0 GR	412	}
	413	/*
	414	* Since Ack Vectors are variable-length, we can not always predict
	415	* their size. To catch exception cases where the space is running out
	416	* on the skb, a separate Sync is scheduled to carry the Ack Vector.
	417	*/
	418	if (len > DCCPAV_MIN_OPTLEN &&
	419	len + dcb->dccpd_opt_len + skb->len > dp->dccps_mss_cache) {
	420	DCCP_WARN("No space left for Ack Vector (%u) on skb (%u+%u), "
	421	"MPS=%u ==> reduce payload size?\n", len, skb->len,
	422	dcb->dccpd_opt_len, dp->dccps_mss_cache);
	423	dp->dccps_sync_scheduled = 1;
	424	return 0;
	425	}
	426	dcb->dccpd_opt_len += len;
7d870936 GR	427
7d870936 GR	428	to = skb_push(skb, len);
b3d14bff	429	len = buflen;
7d870936 GR	430	from = av->av_buf + av->av_buf_head;
	431	tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
	432
	433	for (i = 0; i < nr_opts; ++i) {
	434	int copylen = len;
	435
	436	if (len > DCCP_SINGLE_OPT_MAXLEN)
	437	copylen = DCCP_SINGLE_OPT_MAXLEN;
	438
	439	/*
	440	* RFC 4340, 12.2: Encode the Nonce Echo for this Ack Vector via
	441	* its type; ack_nonce is the sum of all individual buf_nonce's.
	442	*/
	443	nonce ^= av->av_buf_nonce[i];
	444
	445	*to++ = DCCPO_ACK_VECTOR_0 + av->av_buf_nonce[i];
	446	*to++ = copylen + 2;
	447
	448	/* Check if buf_head wraps */
	449	if (from + copylen > tail) {
	450	const u16 tailsize = tail - from;
	451
	452	memcpy(to, from, tailsize);
	453	to += tailsize;
	454	len -= tailsize;
	455	copylen -= tailsize;
	456	from = av->av_buf;
	457	}
	458
	459	memcpy(to, from, copylen);
	460	from += copylen;
	461	to += copylen;
	462	len -= copylen;
	463	}
	464	/*
	465	* Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
	466	*/
d83447f0	467	if (dccp_ackvec_update_records(av, dcb->dccpd_seq, nonce))
7d870936 GR	468	return -ENOBUFS;
	469	return 0;
	470	}
	471
d3710566 GR	472	/**
	473	* dccp_insert_option_mandatory - Mandatory option (5.8.2)
	474	* Note that since we are using skb_push, this function needs to be called
	475	* _after_ inserting the option it is supposed to influence (stack order).
	476	*/
	477	int dccp_insert_option_mandatory(struct sk_buff *skb)
	478	{
	479	if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN)
	480	return -1;
	481
	482	DCCP_SKB_CB(skb)->dccpd_opt_len++;
d58ff351	483	(u8 )skb_push(skb, 1) = DCCPO_MANDATORY;
d3710566 GR	484	return 0;
	485	}
	486
8c862c23 GR	487	/**
	488	* dccp_insert_fn_opt - Insert single Feature-Negotiation option into @skb
	489	* @type: %DCCPO_CHANGE_L, %DCCPO_CHANGE_R, %DCCPO_CONFIRM_L, %DCCPO_CONFIRM_R
	490	* @feat: one out of %dccp_feature_numbers
	491	* @val: NN value or SP array (preferred element first) to copy
	492	* @len: true length of @val in bytes (excluding first element repetition)
	493	* @repeat_first: whether to copy the first element of @val twice
2c53040f	494	*
8c862c23 GR	495	* The last argument is used to construct Confirm options, where the preferred
	496	* value and the preference list appear separately (RFC 4340, 6.3.1). Preference
	497	* lists are kept such that the preferred entry is always first, so we only need
	498	* to copy twice, and avoid the overhead of cloning into a bigger array.
	499	*/
	500	int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat,
	501	u8 *val, u8 len, bool repeat_first)
4829007c	502	{
8c862c23	503	u8 tot_len, *to;
4829007c	504
8c862c23 GR	505	/* take the `Feature' field and possible repetition into account */
	506	if (len > (DCCP_SINGLE_OPT_MAXLEN - 2)) {
	507	DCCP_WARN("length %u for feature %u too large\n", len, feat);
4829007c	508	return -1;
c2f42077	509	}
4829007c	510
8c862c23	511	if (unlikely(val == NULL \|\| len == 0))
3db1cd5c	512	len = repeat_first = false;
8c862c23 GR	513	tot_len = 3 + repeat_first + len;
	514
	515	if (DCCP_SKB_CB(skb)->dccpd_opt_len + tot_len > DCCP_MAX_OPT_LEN) {
	516	DCCP_WARN("packet too small for feature %d option!\n", feat);
	517	return -1;
	518	}
	519	DCCP_SKB_CB(skb)->dccpd_opt_len += tot_len;
4829007c	520
8c862c23	521	to = skb_push(skb, tot_len);
410e27a4	522	*to++ = type;
8c862c23	523	*to++ = tot_len;
410e27a4	524	*to++ = feat;
4829007c	525
8c862c23 GR	526	if (repeat_first)
8c862c23 GR	527	to++ = val;
410e27a4 GR	528	if (len)
410e27a4 GR	529	memcpy(to, val, len);
d0440ee6 GR	530	return 0;
	531	}
	532
af3b867e GR	533	/* The length of all options needs to be a multiple of 4 (5.8) */
	534	static void dccp_insert_option_padding(struct sk_buff *skb)
	535	{
	536	int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
	537
	538	if (padding != 0) {
	539	padding = 4 - padding;
	540	memset(skb_push(skb, padding), 0, padding);
	541	DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
	542	}
	543	}
	544
2d0817d1	545	int dccp_insert_options(struct sock sk, struct sk_buff skb)
7c657876 ACM	546	{
	547	struct dccp_sock *dp = dccp_sk(sk);
	548
	549	DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
	550
4098dce5	551	if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb))
2d0817d1	552	return -1;
7c657876	553
8b7b6c75 GR	554	if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) {
	555
	556	/* Feature Negotiation */
	557	if (dccp_feat_insert_opts(dp, NULL, skb))
2d0817d1	558	return -1;
8b7b6c75 GR	559
	560	if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) {
	561	/*
	562	* Obtain RTT sample from Request/Response exchange.
59b80802	563	* This is currently used for TFRC initialisation.
8b7b6c75	564	*/
a7d13fbf	565	if (dccp_insert_option_timestamp(skb))
8b7b6c75 GR	566	return -1;
8b7b6c75 GR	567
b3d14bff	568	} else if (dccp_ackvec_pending(sk) &&
8b7b6c75 GR	569	dccp_insert_option_ackvec(sk, skb)) {
	570	return -1;
	571	}
7c657876 ACM	572	}
7c657876 ACM	573
507d37cf	574	if (dp->dccps_hc_rx_insert_options) {
2d0817d1 ACM	575	if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
2d0817d1 ACM	576	return -1;
507d37cf ACM	577	dp->dccps_hc_rx_insert_options = 0;
507d37cf ACM	578	}
7c657876	579
b4d4f7c7 GR	580	if (dp->dccps_timestamp_echo != 0 &&
	581	dccp_insert_option_timestamp_echo(dp, NULL, skb))
	582	return -1;
	583
af3b867e GR	584	dccp_insert_option_padding(skb);
	585	return 0;
	586	}
7c657876	587
af3b867e GR	588	int dccp_insert_options_rsk(struct dccp_request_sock dreq, struct sk_buff skb)
	589	{
	590	DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
7c657876	591
8b7b6c75 GR	592	if (dccp_feat_insert_opts(NULL, dreq, skb))
	593	return -1;
	594
59b80802 GR	595	/* Obtain RTT sample from Response/Ack exchange (used by TFRC). */
	596	if (dccp_insert_option_timestamp(skb))
	597	return -1;
	598
af3b867e GR	599	if (dreq->dreq_timestamp_echo != 0 &&
	600	dccp_insert_option_timestamp_echo(NULL, dreq, skb))
	601	return -1;
2d0817d1	602
af3b867e	603	dccp_insert_option_padding(skb);
2d0817d1	604	return 0;
7c657876	605	}