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

/*
 *  net/dccp/minisocks.c
 *
 *  An implementation of the DCCP protocol
 *  Arnaldo Carvalho de Melo <acme@conectiva.com.br>
 *
 *	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/dccp.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/timer.h>

#include <net/sock.h>
#include <net/xfrm.h>
#include <net/inet_timewait_sock.h>

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

struct inet_timewait_death_row dccp_death_row = {
	.sysctl_max_tw_buckets = NR_FILE * 2,
	.period		= DCCP_TIMEWAIT_LEN / INET_TWDR_TWKILL_SLOTS,
	.death_lock	= __SPIN_LOCK_UNLOCKED(dccp_death_row.death_lock),
	.hashinfo	= &dccp_hashinfo,
	.tw_timer	= TIMER_INITIALIZER(inet_twdr_hangman, 0,
					    (unsigned long)&dccp_death_row),
	.twkill_work	= __WORK_INITIALIZER(dccp_death_row.twkill_work,
					     inet_twdr_twkill_work),
/* Short-time timewait calendar */

	.twcal_hand	= -1,
	.twcal_timer	= TIMER_INITIALIZER(inet_twdr_twcal_tick, 0,
					    (unsigned long)&dccp_death_row),
};

EXPORT_SYMBOL_GPL(dccp_death_row);

void dccp_minisock_init(struct dccp_minisock *dmsk)
{
	dmsk->dccpms_sequence_window = sysctl_dccp_feat_sequence_window;
	dmsk->dccpms_send_ack_vector = sysctl_dccp_feat_send_ack_vector;
}

void dccp_time_wait(struct sock *sk, int state, int timeo)
{
	struct inet_timewait_sock *tw = NULL;

	if (dccp_death_row.tw_count < dccp_death_row.sysctl_max_tw_buckets)
		tw = inet_twsk_alloc(sk, state);

	if (tw != NULL) {
		const struct inet_connection_sock *icsk = inet_csk(sk);
		const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1);
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
		if (tw->tw_family == PF_INET6) {
			const struct ipv6_pinfo *np = inet6_sk(sk);
			struct inet6_timewait_sock *tw6;

			tw->tw_ipv6_offset = inet6_tw_offset(sk->sk_prot);
			tw6 = inet6_twsk((struct sock *)tw);
			ipv6_addr_copy(&tw6->tw_v6_daddr, &np->daddr);
			ipv6_addr_copy(&tw6->tw_v6_rcv_saddr, &np->rcv_saddr);
			tw->tw_ipv6only = np->ipv6only;
		}
#endif
		/* Linkage updates. */
		__inet_twsk_hashdance(tw, sk, &dccp_hashinfo);

		/* Get the TIME_WAIT timeout firing. */
		if (timeo < rto)
			timeo = rto;

		tw->tw_timeout = DCCP_TIMEWAIT_LEN;
		if (state == DCCP_TIME_WAIT)
			timeo = DCCP_TIMEWAIT_LEN;

		inet_twsk_schedule(tw, &dccp_death_row, timeo,
				   DCCP_TIMEWAIT_LEN);
		inet_twsk_put(tw);
	} else {
		/* Sorry, if we're out of memory, just CLOSE this
		 * socket up.  We've got bigger problems than
		 * non-graceful socket closings.
		 */
		DCCP_WARN("time wait bucket table overflow\n");
	}

	dccp_done(sk);
}

struct sock *dccp_create_openreq_child(struct sock *sk,
				       const struct request_sock *req,
				       const struct sk_buff *skb)
{
	/*
	 * Step 3: Process LISTEN state
	 *
	 *   (* Generate a new socket and switch to that socket *)
	 *   Set S := new socket for this port pair
	 */
	struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC);

	if (newsk != NULL) {
		struct dccp_request_sock *dreq = dccp_rsk(req);
		struct inet_connection_sock *newicsk = inet_csk(newsk);
		struct dccp_sock *newdp = dccp_sk(newsk);
		struct dccp_minisock *newdmsk = dccp_msk(newsk);

		newdp->dccps_role	    = DCCP_ROLE_SERVER;
		newdp->dccps_hc_rx_ackvec   = NULL;
		newdp->dccps_service_list   = NULL;
		newdp->dccps_service	    = dreq->dreq_service;
		newdp->dccps_timestamp_echo = dreq->dreq_timestamp_echo;
		newdp->dccps_timestamp_time = dreq->dreq_timestamp_time;
		newicsk->icsk_rto	    = DCCP_TIMEOUT_INIT;

		INIT_LIST_HEAD(&newdp->dccps_featneg);
		/*
		 * Step 3: Process LISTEN state
		 *
		 *    Choose S.ISS (initial seqno) or set from Init Cookies
		 *    Initialize S.GAR := S.ISS
		 *    Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
		 */

		/* See dccp_v4_conn_request */
		newdmsk->dccpms_sequence_window = req->rcv_wnd;

		newdp->dccps_gar = newdp->dccps_iss = dreq->dreq_iss;
		dccp_update_gss(newsk, dreq->dreq_iss);

		newdp->dccps_isr = dreq->dreq_isr;
		dccp_update_gsr(newsk, dreq->dreq_isr);

		/*
		 * SWL and AWL are initially adjusted so that they are not less than
		 * the initial Sequence Numbers received and sent, respectively:
		 *	SWL := max(GSR + 1 - floor(W/4), ISR),
		 *	AWL := max(GSS - W' + 1, ISS).
		 * These adjustments MUST be applied only at the beginning of the
		 * connection.
		 */
		dccp_set_seqno(&newdp->dccps_swl,
			       max48(newdp->dccps_swl, newdp->dccps_isr));
		dccp_set_seqno(&newdp->dccps_awl,
			       max48(newdp->dccps_awl, newdp->dccps_iss));

		/*
		 * Activate features after initialising the sequence numbers,
		 * since CCID initialisation may depend on GSS, ISR, ISS etc.
		 */
		if (dccp_feat_activate_values(newsk, &dreq->dreq_featneg)) {
			/* It is still raw copy of parent, so invalidate
			 * destructor and make plain sk_free() */
			newsk->sk_destruct = NULL;
			sk_free(newsk);
			return NULL;
		}
		dccp_init_xmit_timers(newsk);

		DCCP_INC_STATS_BH(DCCP_MIB_PASSIVEOPENS);
	}
	return newsk;
}

EXPORT_SYMBOL_GPL(dccp_create_openreq_child);

/*
 * Process an incoming packet for RESPOND sockets represented
 * as an request_sock.
 */
struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
			    struct request_sock *req,
			    struct request_sock **prev)
{
	struct sock *child = NULL;
	struct dccp_request_sock *dreq = dccp_rsk(req);

	/* Check for retransmitted REQUEST */
	if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) {

		if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_isr)) {
			dccp_pr_debug("Retransmitted REQUEST\n");
			dreq->dreq_isr = DCCP_SKB_CB(skb)->dccpd_seq;
			/*
			 * Send another RESPONSE packet
			 * To protect against Request floods, increment retrans
			 * counter (backoff, monitored by dccp_response_timer).
			 */
			req->retrans++;
			req->rsk_ops->rtx_syn_ack(sk, req);
		}
		/* Network Duplicate, discard packet */
		return NULL;
	}

	DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR;

	if (dccp_hdr(skb)->dccph_type != DCCP_PKT_ACK &&
	    dccp_hdr(skb)->dccph_type != DCCP_PKT_DATAACK)
		goto drop;

	/* Invalid ACK */
	if (DCCP_SKB_CB(skb)->dccpd_ack_seq != dreq->dreq_iss) {
		dccp_pr_debug("Invalid ACK number: ack_seq=%llu, "
			      "dreq_iss=%llu\n",
			      (unsigned long long)
			      DCCP_SKB_CB(skb)->dccpd_ack_seq,
			      (unsigned long long) dreq->dreq_iss);
		goto drop;
	}

	if (dccp_parse_options(sk, dreq, skb))
		 goto drop;

	child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL);
	if (child == NULL)
		goto listen_overflow;

	inet_csk_reqsk_queue_unlink(sk, req, prev);
	inet_csk_reqsk_queue_removed(sk, req);
	inet_csk_reqsk_queue_add(sk, req, child);
out:
	return child;
listen_overflow:
	dccp_pr_debug("listen_overflow!\n");
	DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
drop:
	if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET)
		req->rsk_ops->send_reset(sk, skb);

	inet_csk_reqsk_queue_drop(sk, req, prev);
	goto out;
}

EXPORT_SYMBOL_GPL(dccp_check_req);

/*
 *  Queue segment on the new socket if the new socket is active,
 *  otherwise we just shortcircuit this and continue with
 *  the new socket.
 */
int dccp_child_process(struct sock *parent, struct sock *child,
		       struct sk_buff *skb)
{
	int ret = 0;
	const int state = child->sk_state;

	if (!sock_owned_by_user(child)) {
		ret = dccp_rcv_state_process(child, skb, dccp_hdr(skb),
					     skb->len);

		/* Wakeup parent, send SIGIO */
		if (state == DCCP_RESPOND && child->sk_state != state)
			parent->sk_data_ready(parent, 0);
	} else {
		/* Alas, it is possible again, because we do lookup
		 * in main socket hash table and lock on listening
		 * socket does not protect us more.
		 */
		sk_add_backlog(child, skb);
	}

	bh_unlock_sock(child);
	sock_put(child);
	return ret;
}

EXPORT_SYMBOL_GPL(dccp_child_process);

void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
			 struct request_sock *rsk)
{
	DCCP_BUG("DCCP-ACK packets are never sent in LISTEN/RESPOND state");
}

EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack);

int dccp_reqsk_init(struct request_sock *req,
		    struct dccp_sock const *dp, struct sk_buff const *skb)
{
	struct dccp_request_sock *dreq = dccp_rsk(req);

	inet_rsk(req)->rmt_port	  = dccp_hdr(skb)->dccph_sport;
	inet_rsk(req)->loc_port	  = dccp_hdr(skb)->dccph_dport;
	inet_rsk(req)->acked	  = 0;
	req->rcv_wnd		  = sysctl_dccp_feat_sequence_window;
	dreq->dreq_timestamp_echo = 0;

	/* inherit feature negotiation options from listening socket */
	return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg);
}

EXPORT_SYMBOL_GPL(dccp_reqsk_init);
Commit	Line	Data
7c657876 ACM	1	/*
	2	* net/dccp/minisocks.c
	3	*
	4	* An implementation of the DCCP protocol
	5	* Arnaldo Carvalho de Melo <acme@conectiva.com.br>
	6	*
	7	* This program is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License
	9	* as published by the Free Software Foundation; either version
	10	* 2 of the License, or (at your option) any later version.
	11	*/
	12
7c657876	13	#include <linux/dccp.h>
8a73cd09	14	#include <linux/kernel.h>
7c657876 ACM	15	#include <linux/skbuff.h>
	16	#include <linux/timer.h>
	17
	18	#include <net/sock.h>
	19	#include <net/xfrm.h>
	20	#include <net/inet_timewait_sock.h>
	21
ae31c339	22	#include "ackvec.h"
7c657876 ACM	23	#include "ccid.h"
7c657876 ACM	24	#include "dccp.h"
afe00251	25	#include "feat.h"
7c657876	26
64cf1e5d ACM	27	struct inet_timewait_death_row dccp_death_row = {
	28	.sysctl_max_tw_buckets = NR_FILE * 2,
	29	.period = DCCP_TIMEWAIT_LEN / INET_TWDR_TWKILL_SLOTS,
4ef8d0ae	30	.death_lock = __SPIN_LOCK_UNLOCKED(dccp_death_row.death_lock),
64cf1e5d ACM	31	.hashinfo = &dccp_hashinfo,
	32	.tw_timer = TIMER_INITIALIZER(inet_twdr_hangman, 0,
	33	(unsigned long)&dccp_death_row),
	34	.twkill_work = __WORK_INITIALIZER(dccp_death_row.twkill_work,
c4028958	35	inet_twdr_twkill_work),
64cf1e5d ACM	36	/* Short-time timewait calendar */
	37
	38	.twcal_hand = -1,
	39	.twcal_timer = TIMER_INITIALIZER(inet_twdr_twcal_tick, 0,
	40	(unsigned long)&dccp_death_row),
	41	};
	42
f21e68ca ACM	43	EXPORT_SYMBOL_GPL(dccp_death_row);
f21e68ca ACM	44
451bc047 GR	45	void dccp_minisock_init(struct dccp_minisock *dmsk)
	46	{
	47	dmsk->dccpms_sequence_window = sysctl_dccp_feat_sequence_window;
451bc047	48	dmsk->dccpms_send_ack_vector = sysctl_dccp_feat_send_ack_vector;
451bc047 GR	49	}
451bc047 GR	50
7c657876 ACM	51	void dccp_time_wait(struct sock *sk, int state, int timeo)
7c657876 ACM	52	{
64cf1e5d	53	struct inet_timewait_sock *tw = NULL;
7c657876	54
64cf1e5d ACM	55	if (dccp_death_row.tw_count < dccp_death_row.sysctl_max_tw_buckets)
	56	tw = inet_twsk_alloc(sk, state);
	57
	58	if (tw != NULL) {
	59	const struct inet_connection_sock *icsk = inet_csk(sk);
	60	const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1);
3df80d93 ACM	61	#if defined(CONFIG_IPV6) \|\| defined(CONFIG_IPV6_MODULE)
	62	if (tw->tw_family == PF_INET6) {
	63	const struct ipv6_pinfo *np = inet6_sk(sk);
	64	struct inet6_timewait_sock *tw6;
64cf1e5d	65
3df80d93 ACM	66	tw->tw_ipv6_offset = inet6_tw_offset(sk->sk_prot);
	67	tw6 = inet6_twsk((struct sock *)tw);
	68	ipv6_addr_copy(&tw6->tw_v6_daddr, &np->daddr);
	69	ipv6_addr_copy(&tw6->tw_v6_rcv_saddr, &np->rcv_saddr);
	70	tw->tw_ipv6only = np->ipv6only;
	71	}
	72	#endif
64cf1e5d ACM	73	/* Linkage updates. */
	74	__inet_twsk_hashdance(tw, sk, &dccp_hashinfo);
	75
	76	/* Get the TIME_WAIT timeout firing. */
	77	if (timeo < rto)
	78	timeo = rto;
	79
	80	tw->tw_timeout = DCCP_TIMEWAIT_LEN;
	81	if (state == DCCP_TIME_WAIT)
	82	timeo = DCCP_TIMEWAIT_LEN;
	83
	84	inet_twsk_schedule(tw, &dccp_death_row, timeo,
	85	DCCP_TIMEWAIT_LEN);
	86	inet_twsk_put(tw);
	87	} else {
	88	/* Sorry, if we're out of memory, just CLOSE this
	89	* socket up. We've got bigger problems than
	90	* non-graceful socket closings.
	91	*/
59348b19	92	DCCP_WARN("time wait bucket table overflow\n");
64cf1e5d ACM	93	}
	94
	95	dccp_done(sk);
7c657876 ACM	96	}
	97
	98	struct sock dccp_create_openreq_child(struct sock sk,
	99	const struct request_sock *req,
	100	const struct sk_buff *skb)
	101	{
	102	/*
	103	* Step 3: Process LISTEN state
	104	*
d83ca5ac GR	105	* (* Generate a new socket and switch to that socket *)
d83ca5ac GR	106	* Set S := new socket for this port pair
7c657876 ACM	107	*/
	108	struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC);
	109
	110	if (newsk != NULL) {
192b27ff	111	struct dccp_request_sock *dreq = dccp_rsk(req);
99c72ce0	112	struct inet_connection_sock *newicsk = inet_csk(newsk);
7c657876	113	struct dccp_sock *newdp = dccp_sk(newsk);
a4bf3902	114	struct dccp_minisock *newdmsk = dccp_msk(newsk);
7c657876	115
b4d4f7c7 GR	116	newdp->dccps_role = DCCP_ROLE_SERVER;
	117	newdp->dccps_hc_rx_ackvec = NULL;
	118	newdp->dccps_service_list = NULL;
	119	newdp->dccps_service = dreq->dreq_service;
	120	newdp->dccps_timestamp_echo = dreq->dreq_timestamp_echo;
	121	newdp->dccps_timestamp_time = dreq->dreq_timestamp_time;
	122	newicsk->icsk_rto = DCCP_TIMEOUT_INIT;
7c657876	123
ac75773c	124	INIT_LIST_HEAD(&newdp->dccps_featneg);
7c657876 ACM	125	/*
	126	* Step 3: Process LISTEN state
	127	*
d83ca5ac GR	128	* Choose S.ISS (initial seqno) or set from Init Cookies
	129	* Initialize S.GAR := S.ISS
	130	* Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
7c657876 ACM	131	*/
	132
	133	/* See dccp_v4_conn_request */
a4bf3902	134	newdmsk->dccpms_sequence_window = req->rcv_wnd;
7c657876	135
be4c798a	136	newdp->dccps_gar = newdp->dccps_iss = dreq->dreq_iss;
7c657876 ACM	137	dccp_update_gss(newsk, dreq->dreq_iss);
7c657876 ACM	138
be4c798a GR	139	newdp->dccps_isr = dreq->dreq_isr;
	140	dccp_update_gsr(newsk, dreq->dreq_isr);
	141
03ace394 ACM	142	/*
	143	* SWL and AWL are initially adjusted so that they are not less than
	144	* the initial Sequence Numbers received and sent, respectively:
	145	* SWL := max(GSR + 1 - floor(W/4), ISR),
	146	* AWL := max(GSS - W' + 1, ISS).
	147	* These adjustments MUST be applied only at the beginning of the
	148	* connection.
	149	*/
	150	dccp_set_seqno(&newdp->dccps_swl,
	151	max48(newdp->dccps_swl, newdp->dccps_isr));
	152	dccp_set_seqno(&newdp->dccps_awl,
	153	max48(newdp->dccps_awl, newdp->dccps_iss));
	154
192b27ff GR	155	/*
	156	* Activate features after initialising the sequence numbers,
	157	* since CCID initialisation may depend on GSS, ISR, ISS etc.
	158	*/
	159	if (dccp_feat_activate_values(newsk, &dreq->dreq_featneg)) {
	160	/* It is still raw copy of parent, so invalidate
	161	* destructor and make plain sk_free() */
	162	newsk->sk_destruct = NULL;
	163	sk_free(newsk);
	164	return NULL;
	165	}
7c657876 ACM	166	dccp_init_xmit_timers(newsk);
	167
	168	DCCP_INC_STATS_BH(DCCP_MIB_PASSIVEOPENS);
	169	}
	170	return newsk;
	171	}
	172
f21e68ca ACM	173	EXPORT_SYMBOL_GPL(dccp_create_openreq_child);
f21e68ca ACM	174
8109b02b	175	/*
7c657876 ACM	176	* Process an incoming packet for RESPOND sockets represented
	177	* as an request_sock.
	178	*/
	179	struct sock dccp_check_req(struct sock sk, struct sk_buff *skb,
	180	struct request_sock *req,
	181	struct request_sock **prev)
	182	{
	183	struct sock *child = NULL;
8109616e	184	struct dccp_request_sock *dreq = dccp_rsk(req);
7c657876 ACM	185
	186	/* Check for retransmitted REQUEST */
	187	if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) {
7c657876	188
e11d9d30	189	if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_isr)) {
7c657876	190	dccp_pr_debug("Retransmitted REQUEST\n");
e11d9d30 GR	191	dreq->dreq_isr = DCCP_SKB_CB(skb)->dccpd_seq;
	192	/*
	193	* Send another RESPONSE packet
	194	* To protect against Request floods, increment retrans
	195	* counter (backoff, monitored by dccp_response_timer).
	196	*/
	197	req->retrans++;
fd80eb94	198	req->rsk_ops->rtx_syn_ack(sk, req);
7c657876 ACM	199	}
	200	/* Network Duplicate, discard packet */
	201	return NULL;
	202	}
	203
	204	DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR;
	205
	206	if (dccp_hdr(skb)->dccph_type != DCCP_PKT_ACK &&
	207	dccp_hdr(skb)->dccph_type != DCCP_PKT_DATAACK)
	208	goto drop;
	209
	210	/* Invalid ACK */
8109616e	211	if (DCCP_SKB_CB(skb)->dccpd_ack_seq != dreq->dreq_iss) {
7690af3f ACM	212	dccp_pr_debug("Invalid ACK number: ack_seq=%llu, "
7690af3f ACM	213	"dreq_iss=%llu\n",
f6ccf554 DM	214	(unsigned long long)
f6ccf554 DM	215	DCCP_SKB_CB(skb)->dccpd_ack_seq,
8109616e	216	(unsigned long long) dreq->dreq_iss);
7c657876 ACM	217	goto drop;
	218	}
	219
8109616e GR	220	if (dccp_parse_options(sk, dreq, skb))
	221	goto drop;
	222
57cca05a	223	child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL);
7c657876 ACM	224	if (child == NULL)
	225	goto listen_overflow;
	226
7c657876 ACM	227	inet_csk_reqsk_queue_unlink(sk, req, prev);
	228	inet_csk_reqsk_queue_removed(sk, req);
	229	inet_csk_reqsk_queue_add(sk, req, child);
	230	out:
	231	return child;
	232	listen_overflow:
	233	dccp_pr_debug("listen_overflow!\n");
	234	DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
	235	drop:
	236	if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET)
cfb6eeb4	237	req->rsk_ops->send_reset(sk, skb);
7c657876 ACM	238
	239	inet_csk_reqsk_queue_drop(sk, req, prev);
	240	goto out;
	241	}
	242
f21e68ca ACM	243	EXPORT_SYMBOL_GPL(dccp_check_req);
f21e68ca ACM	244
7c657876 ACM	245	/*
	246	* Queue segment on the new socket if the new socket is active,
	247	* otherwise we just shortcircuit this and continue with
	248	* the new socket.
	249	*/
	250	int dccp_child_process(struct sock parent, struct sock child,
	251	struct sk_buff *skb)
	252	{
	253	int ret = 0;
	254	const int state = child->sk_state;
	255
	256	if (!sock_owned_by_user(child)) {
7690af3f ACM	257	ret = dccp_rcv_state_process(child, skb, dccp_hdr(skb),
7690af3f ACM	258	skb->len);
7c657876 ACM	259
	260	/* Wakeup parent, send SIGIO */
	261	if (state == DCCP_RESPOND && child->sk_state != state)
	262	parent->sk_data_ready(parent, 0);
	263	} else {
	264	/* Alas, it is possible again, because we do lookup
	265	* in main socket hash table and lock on listening
	266	* socket does not protect us more.
	267	*/
	268	sk_add_backlog(child, skb);
	269	}
	270
	271	bh_unlock_sock(child);
	272	sock_put(child);
	273	return ret;
	274	}
f21e68ca ACM	275
f21e68ca ACM	276	EXPORT_SYMBOL_GPL(dccp_child_process);
8a73cd09	277
6edafaaf GJ	278	void dccp_reqsk_send_ack(struct sock sk, struct sk_buff skb,
6edafaaf GJ	279	struct request_sock *rsk)
8a73cd09	280	{
59348b19	281	DCCP_BUG("DCCP-ACK packets are never sent in LISTEN/RESPOND state");
8a73cd09 GR	282	}
	283
	284	EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack);
cf557926	285
ac75773c GR	286	int dccp_reqsk_init(struct request_sock *req,
ac75773c GR	287	struct dccp_sock const dp, struct sk_buff const skb)
cf557926	288	{
b4d4f7c7 GR	289	struct dccp_request_sock *dreq = dccp_rsk(req);
	290
	291	inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
944f7502	292	inet_rsk(req)->loc_port = dccp_hdr(skb)->dccph_dport;
b4d4f7c7 GR	293	inet_rsk(req)->acked = 0;
	294	req->rcv_wnd = sysctl_dccp_feat_sequence_window;
	295	dreq->dreq_timestamp_echo = 0;
ac75773c GR	296
	297	/* inherit feature negotiation options from listening socket */
	298	return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg);
cf557926 GR	299	}
	300
	301	EXPORT_SYMBOL_GPL(dccp_reqsk_init);