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[DCCP]: Move the ack vector code to net/dccp/ackvec.[ch]

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Isolating it, that will be used when we introduce a CCID2 (TCP-Like)
implementation.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Arnaldo Carvalho de Melo 2005-09-18 00:17:51 -07:00 committed by David S. Miller
parent 21f130a237
commit ae31c3399d
10 changed files with 612 additions and 631 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
include/linux/dccp.h
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@ -353,14 +353,8 @@ static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
extern struct inet_timewait_death_row dccp_death_row;
/* Read about the ECN nonce to see why it is 253 */
#define DCCP_MAX_ACK_VECTOR_LEN 253
struct dccp_options_received {
u32 dccpor_ndp:24,
dccpor_ack_vector_len:8;
u32 dccpor_ack_vector_idx:10;
/* 22 bits hole, try to pack */
u32 dccpor_ndp; /* only 24 bits */
u32 dccpor_timestamp;
u32 dccpor_timestamp_echo;
u32 dccpor_elapsed_time;
@ -394,6 +388,8 @@ static inline int dccp_list_has_service(const struct dccp_service_list *sl,
return 0;
}
struct dccp_ackvec;
/**
* struct dccp_sock - DCCP socket state
*
@ -414,7 +410,7 @@ static inline int dccp_list_has_service(const struct dccp_service_list *sl,
* @dccps_packet_size - Set thru setsockopt
* @dccps_role - Role of this sock, one of %dccp_role
* @dccps_ndp_count - number of Non Data Packets since last data packet
* @dccps_hc_rx_ackpkts - receiver half connection acked packets
* @dccps_hc_rx_ackvec - rx half connection ack vector
*/
struct dccp_sock {
/* inet_connection_sock has to be the first member of dccp_sock */
@ -439,7 +435,7 @@ struct dccp_sock {
__u32 dccps_pmtu_cookie;
__u32 dccps_mss_cache;
struct dccp_options dccps_options;
struct dccp_ackpkts *dccps_hc_rx_ackpkts;
struct dccp_ackvec *dccps_hc_rx_ackvec;
void *dccps_hc_rx_ccid_private;
void *dccps_hc_tx_ccid_private;
struct ccid *dccps_hc_rx_ccid;

2
net/dccp/Makefile
View File

@ -3,6 +3,8 @@ obj-$(CONFIG_IP_DCCP) += dccp.o
dccp-y := ccid.o input.o ipv4.o minisocks.o options.o output.o proto.o \
timer.o
dccp-$(CONFIG_IP_DCCP_ACKVEC) += ackvec.o
obj-$(CONFIG_INET_DCCP_DIAG) += dccp_diag.o
dccp_diag-y := diag.o

419
net/dccp/ackvec.c Normal file
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@ -0,0 +1,419 @@
/*
* net/dccp/ackvec.c
*
* An implementation of the DCCP protocol
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
*
* 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; version 2 of the License;
*/
#include "ackvec.h"
#include "dccp.h"
#include <linux/dccp.h>
#include <linux/skbuff.h>
#include <net/sock.h>
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;
int len = av->dccpav_vec_len + 2;
struct timeval now;
u32 elapsed_time;
unsigned char *to, *from;
dccp_timestamp(sk, &now);
elapsed_time = timeval_delta(&now, &av->dccpav_time) / 10;
if (elapsed_time != 0)
dccp_insert_option_elapsed_time(sk, skb, elapsed_time);
if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
return -1;
/*
* XXX: now we have just one ack vector sent record, so
* we have to wait for it to be cleared.
*
* Of course this is not acceptable, but this is just for
* basic testing now.
*/
if (av->dccpav_ack_seqno != DCCP_MAX_SEQNO + 1)
return -1;
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
to = skb_push(skb, len);
*to++ = DCCPO_ACK_VECTOR_0;
*to++ = len;
len = av->dccpav_vec_len;
from = av->dccpav_buf + av->dccpav_buf_head;
/* Check if buf_head wraps */
if (av->dccpav_buf_head + len > av->dccpav_vec_len) {
const u32 tailsize = (av->dccpav_vec_len - av->dccpav_buf_head);
memcpy(to, from, tailsize);
to += tailsize;
len -= tailsize;
from = av->dccpav_buf;
}
memcpy(to, from, len);
/*
* From draft-ietf-dccp-spec-11.txt:
*
* For each acknowledgement it sends, the HC-Receiver will add an
* acknowledgement record. ack_seqno will equal the HC-Receiver
* sequence number it used for the ack packet; ack_ptr will equal
* buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
* equal buf_nonce.
*
* This implemention uses just one ack record for now.
*/
av->dccpav_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
av->dccpav_ack_ptr = av->dccpav_buf_head;
av->dccpav_ack_ackno = av->dccpav_buf_ackno;
av->dccpav_ack_nonce = av->dccpav_buf_nonce;
av->dccpav_sent_len = av->dccpav_vec_len;
dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
"ack_ackno=%llu\n",
debug_prefix, av->dccpav_sent_len,
(unsigned long long)av->dccpav_ack_seqno,
(unsigned long long)av->dccpav_ack_ackno);
return -1;
}
struct dccp_ackvec *dccp_ackvec_alloc(const unsigned int len,
const unsigned int __nocast priority)
{
struct dccp_ackvec *av = kmalloc(sizeof(*av) + len, priority);
if (av != NULL) {
av->dccpav_buf_len = len;
av->dccpav_buf_head =
av->dccpav_buf_tail = av->dccpav_buf_len - 1;
av->dccpav_buf_ackno =
av->dccpav_ack_ackno = av->dccpav_ack_seqno = ~0LLU;
av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0;
av->dccpav_ack_ptr = 0;
av->dccpav_time.tv_sec = 0;
av->dccpav_time.tv_usec = 0;
av->dccpav_sent_len = av->dccpav_vec_len = 0;
}
return av;
}
void dccp_ackvec_free(struct dccp_ackvec *av)
{
kfree(av);
}
static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av,
const unsigned int index)
{
return av->dccpav_buf[index] & DCCP_ACKVEC_STATE_MASK;
}
static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av,
const unsigned int index)
{
return av->dccpav_buf[index] & DCCP_ACKVEC_LEN_MASK;
}
/*
* If several packets are missing, the HC-Receiver may prefer to enter multiple
* bytes with run length 0, rather than a single byte with a larger run length;
* this simplifies table updates if one of the missing packets arrives.
*/
static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
const unsigned int packets,
const unsigned char state)
{
unsigned int gap;
signed long new_head;
if (av->dccpav_vec_len + packets > av->dccpav_buf_len)
return -ENOBUFS;
gap = packets - 1;
new_head = av->dccpav_buf_head - packets;
if (new_head < 0) {
if (gap > 0) {
memset(av->dccpav_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED,
gap + new_head + 1);
gap = -new_head;
}
new_head += av->dccpav_buf_len;
}
av->dccpav_buf_head = new_head;
if (gap > 0)
memset(av->dccpav_buf + av->dccpav_buf_head + 1,
DCCP_ACKVEC_STATE_NOT_RECEIVED, gap);
av->dccpav_buf[av->dccpav_buf_head] = state;
av->dccpav_vec_len += packets;
return 0;
}
/*
* Implements the draft-ietf-dccp-spec-11.txt Appendix A
*/
int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
const u64 ackno, const u8 state)
{
/*
* Check at the right places if the buffer is full, if it is, tell the
* caller to start dropping packets till the HC-Sender acks our ACK
* vectors, when we will free up space in dccpav_buf.
*
* We may well decide to do buffer compression, etc, but for now lets
* just drop.
*
* From Appendix A:
*
* Of course, the circular buffer may overflow, either when the
* HC-Sender is sending data at a very high rate, when the
* HC-Receiver's acknowledgements are not reaching the HC-Sender,
* or when the HC-Sender is forgetting to acknowledge those acks
* (so the HC-Receiver is unable to clean up old state). In this
* case, the HC-Receiver should either compress the buffer (by
* increasing run lengths when possible), transfer its state to
* a larger buffer, or, as a last resort, drop all received
* packets, without processing them whatsoever, until its buffer
* shrinks again.
*/
/* See if this is the first ackno being inserted */
if (av->dccpav_vec_len == 0) {
av->dccpav_buf[av->dccpav_buf_head] = state;
av->dccpav_vec_len = 1;
} else if (after48(ackno, av->dccpav_buf_ackno)) {
const u64 delta = dccp_delta_seqno(av->dccpav_buf_ackno,
ackno);
/*
* Look if the state of this packet is the same as the
* previous ackno and if so if we can bump the head len.
*/
if (delta == 1 &&
dccp_ackvec_state(av, av->dccpav_buf_head) == state &&
(dccp_ackvec_len(av, av->dccpav_buf_head) <
DCCP_ACKVEC_LEN_MASK))
av->dccpav_buf[av->dccpav_buf_head]++;
else if (dccp_ackvec_set_buf_head_state(av, delta, state))
return -ENOBUFS;
} else {
/*
* A.1.2. Old Packets
*
* When a packet with Sequence Number S arrives, and
* S <= buf_ackno, the HC-Receiver will scan the table
* for the byte corresponding to S. (Indexing structures
* could reduce the complexity of this scan.)
*/
u64 delta = dccp_delta_seqno(ackno, av->dccpav_buf_ackno);
unsigned int index = av->dccpav_buf_head;
while (1) {
const u8 len = dccp_ackvec_len(av, index);
const u8 state = dccp_ackvec_state(av, index);
/*
* valid packets not yet in dccpav_buf have a reserved
* entry, with a len equal to 0.
*/
if (state == DCCP_ACKVEC_STATE_NOT_RECEIVED &&
len == 0 && delta == 0) { /* Found our
reserved seat! */
dccp_pr_debug("Found %llu reserved seat!\n",
(unsigned long long)ackno);
av->dccpav_buf[index] = state;
goto out;
}
/* len == 0 means one packet */
if (delta < len + 1)
goto out_duplicate;
delta -= len + 1;
if (++index == av->dccpav_buf_len)
index = 0;
}
}
av->dccpav_buf_ackno = ackno;
dccp_timestamp(sk, &av->dccpav_time);
out:
dccp_pr_debug("");
return 0;
out_duplicate:
/* Duplicate packet */
dccp_pr_debug("Received a dup or already considered lost "
"packet: %llu\n", (unsigned long long)ackno);
return -EILSEQ;
}
#ifdef CONFIG_IP_DCCP_DEBUG
void dccp_ackvector_print(const u64 ackno, const unsigned char *vector, int len)
{
if (!dccp_debug)
return;
printk("ACK vector len=%d, ackno=%llu |", len,
(unsigned long long)ackno);
while (len--) {
const u8 state = (*vector & DCCP_ACKVEC_STATE_MASK) >> 6;
const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
printk("%d,%d|", state, rl);
++vector;
}
printk("\n");
}
void dccp_ackvec_print(const struct dccp_ackvec *av)
{
dccp_ackvector_print(av->dccpav_buf_ackno,
av->dccpav_buf + av->dccpav_buf_head,
av->dccpav_vec_len);
}
#endif
static void dccp_ackvec_trow_away_ack_record(struct dccp_ackvec *av)
{
/*
* As we're keeping track of the ack vector size (dccpav_vec_len) and
* the sent ack vector size (dccpav_sent_len) we don't need
* dccpav_buf_tail at all, but keep this code here as in the future
* we'll implement a vector of ack records, as suggested in
* draft-ietf-dccp-spec-11.txt Appendix A. -acme
*/
#if 0
av->dccpav_buf_tail = av->dccpav_ack_ptr + 1;
if (av->dccpav_buf_tail >= av->dccpav_vec_len)
av->dccpav_buf_tail -= av->dccpav_vec_len;
#endif
av->dccpav_vec_len -= av->dccpav_sent_len;
}
void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk,
const u64 ackno)
{
/* Check if we actually sent an ACK vector */
if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1)
return;
if (ackno == av->dccpav_ack_seqno) {
#ifdef CONFIG_IP_DCCP_DEBUG
struct dccp_sock *dp = dccp_sk(sk);
const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
"CLIENT rx ack: " : "server rx ack: ";
#endif
dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "
"ack_ackno=%llu, ACKED!\n",
debug_prefix, 1,
(unsigned long long)av->dccpav_ack_seqno,
(unsigned long long)av->dccpav_ack_ackno);
dccp_ackvec_trow_away_ack_record(av);
av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1;
}
}
static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
struct sock *sk, u64 ackno,
const unsigned char len,
const unsigned char *vector)
{
unsigned char i;
/* Check if we actually sent an ACK vector */
if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1)
return;
/*
* We're in the receiver half connection, so if the received an ACK
* vector ackno (e.g. 50) before dccpav_ack_seqno (e.g. 52), we're
* not interested.
*
* Extra explanation with example:
*
* if we received an ACK vector with ackno 50, it can only be acking
* 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent).
*/
/* dccp_pr_debug("is %llu < %llu? ", ackno, av->dccpav_ack_seqno); */
if (before48(ackno, av->dccpav_ack_seqno)) {
/* dccp_pr_debug_cat("yes\n"); */
return;
}
/* dccp_pr_debug_cat("no\n"); */
i = len;
while (i--) {
const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
u64 ackno_end_rl;
dccp_set_seqno(&ackno_end_rl, ackno - rl);
/*
* dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl,
* av->dccpav_ack_seqno, ackno);
*/
if (between48(av->dccpav_ack_seqno, ackno_end_rl, ackno)) {
const u8 state = (*vector &
DCCP_ACKVEC_STATE_MASK) >> 6;
/* dccp_pr_debug_cat("yes\n"); */
if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
#ifdef CONFIG_IP_DCCP_DEBUG
struct dccp_sock *dp = dccp_sk(sk);
const char *debug_prefix =
dp->dccps_role == DCCP_ROLE_CLIENT ?
"CLIENT rx ack: " : "server rx ack: ";
#endif
dccp_pr_debug("%sACK vector 0, len=%d, "
"ack_seqno=%llu, ack_ackno=%llu, "
"ACKED!\n",
debug_prefix, len,
(unsigned long long)
av->dccpav_ack_seqno,
(unsigned long long)
av->dccpav_ack_ackno);
dccp_ackvec_trow_away_ack_record(av);
}
/*
* If dccpav_ack_seqno was not received, no problem
* we'll send another ACK vector.
*/
av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1;
break;
}
/* dccp_pr_debug_cat("no\n"); */
dccp_set_seqno(&ackno, ackno_end_rl - 1);
++vector;
}
}
int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
const u8 opt, const u8 *value, const u8 len)
{
if (len > DCCP_MAX_ACKVEC_LEN)
return -1;
/* dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq, value, len); */
dccp_ackvec_check_rcv_ackvector(dccp_sk(sk)->dccps_hc_rx_ackvec, sk,
DCCP_SKB_CB(skb)->dccpd_ack_seq,
len, value);
return 0;
}

133
net/dccp/ackvec.h Normal file
View File

@ -0,0 +1,133 @@
#ifndef _ACKVEC_H
#define _ACKVEC_H
/*
* net/dccp/ackvec.h
*
* An implementation of the DCCP protocol
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/config.h>
#include <linux/compiler.h>
#include <linux/time.h>
#include <linux/types.h>
/* Read about the ECN nonce to see why it is 253 */
#define DCCP_MAX_ACKVEC_LEN 253
#define DCCP_ACKVEC_STATE_RECEIVED 0
#define DCCP_ACKVEC_STATE_ECN_MARKED (1 << 6)
#define DCCP_ACKVEC_STATE_NOT_RECEIVED (3 << 6)
#define DCCP_ACKVEC_STATE_MASK 0xC0 /* 11000000 */
#define DCCP_ACKVEC_LEN_MASK 0x3F /* 00111111 */
/** struct dccp_ackvec - ack vector
*
* This data structure is the one defined in the DCCP draft
* Appendix A.
*
* @dccpav_buf_head - circular buffer head
* @dccpav_buf_tail - circular buffer tail
* @dccpav_buf_ackno - ack # of the most recent packet acknowledgeable in the
* buffer (i.e. %dccpav_buf_head)
* @dccpav_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
* by the buffer with State 0
*
* Additionally, the HC-Receiver must keep some information about the
* Ack Vectors it has recently sent. For each packet sent carrying an
* Ack Vector, it remembers four variables:
*
* @dccpav_ack_seqno - the Sequence Number used for the packet
* (HC-Receiver seqno)
* @dccpav_ack_ptr - the value of buf_head at the time of acknowledgement.
* @dccpav_ack_ackno - the Acknowledgement Number used for the packet
* (HC-Sender seqno)
* @dccpav_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
*
* @dccpav_buf_len - circular buffer length
* @dccpav_time - the time in usecs
* @dccpav_buf - circular buffer of acknowledgeable packets
*/
struct dccp_ackvec {
unsigned int dccpav_buf_head;
unsigned int dccpav_buf_tail;
u64 dccpav_buf_ackno;
u64 dccpav_ack_seqno;
u64 dccpav_ack_ackno;
unsigned int dccpav_ack_ptr;
unsigned int dccpav_sent_len;
unsigned int dccpav_vec_len;
unsigned int dccpav_buf_len;
struct timeval dccpav_time;
u8 dccpav_buf_nonce;
u8 dccpav_ack_nonce;
u8 dccpav_buf[0];
};
struct sock;
struct sk_buff;
#ifdef CONFIG_IP_DCCP_ACKVEC
extern struct dccp_ackvec *dccp_ackvec_alloc(unsigned int len,
const unsigned int __nocast priority);
extern void dccp_ackvec_free(struct dccp_ackvec *av);
extern int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
const u64 ackno, const u8 state);
extern void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
struct sock *sk, const u64 ackno);
extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
const u8 opt, const u8 *value, const u8 len);
extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);
static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
{
return av->dccpav_sent_len != av->dccpav_vec_len;
}
#else /* CONFIG_IP_DCCP_ACKVEC */
static inline struct dccp_ackvec *dccp_ackvec_alloc(unsigned int len,
const unsigned int __nocast priority)
{
return NULL;
}
static inline void dccp_ackvec_free(struct dccp_ackvec *av)
{
}
static inline int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
const u64 ackno, const u8 state)
{
return -1;
}
static inline void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
struct sock *sk, const u64 ackno)
{
}
static inline int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
const u8 opt, const u8 *value, const u8 len)
{
return -1;
}
static inline int dccp_insert_option_ackvec(const struct sock *sk,
const struct sk_buff *skb)
{
return -1;
}
static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
{
return 0;
}
#endif /* CONFIG_IP_DCCP_ACKVEC */
#endif /* _ACKVEC_H */

82
net/dccp/dccp.h
View File

@ -17,6 +17,7 @@
#include <net/snmp.h>
#include <net/sock.h>
#include <net/tcp.h>
#include "ackvec.h"
#ifdef CONFIG_IP_DCCP_DEBUG
extern int dccp_debug;
@ -358,6 +359,17 @@ static inline void dccp_update_gss(struct sock *sk, u64 seq)
(dp->dccps_gss -
dp->dccps_options.dccpo_sequence_window + 1));
}
static inline int dccp_ack_pending(const struct sock *sk)
{
const struct dccp_sock *dp = dccp_sk(sk);
return dp->dccps_timestamp_echo != 0 ||
#ifdef CONFIG_IP_DCCP_ACKVEC
(dp->dccps_options.dccpo_send_ack_vector &&
dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) ||
#endif
inet_csk_ack_scheduled(sk);
}
extern void dccp_insert_options(struct sock *sk, struct sk_buff *skb);
extern void dccp_insert_option_elapsed_time(struct sock *sk,
@ -371,65 +383,6 @@ extern void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
extern struct socket *dccp_ctl_socket;
#define DCCP_ACKPKTS_STATE_RECEIVED 0
#define DCCP_ACKPKTS_STATE_ECN_MARKED (1 << 6)
#define DCCP_ACKPKTS_STATE_NOT_RECEIVED (3 << 6)
#define DCCP_ACKPKTS_STATE_MASK 0xC0 /* 11000000 */
#define DCCP_ACKPKTS_LEN_MASK 0x3F /* 00111111 */
/** struct dccp_ackpkts - acknowledgeable packets
*
* This data structure is the one defined in the DCCP draft
* Appendix A.
*
* @dccpap_buf_head - circular buffer head
* @dccpap_buf_tail - circular buffer tail
* @dccpap_buf_ackno - ack # of the most recent packet acknowledgeable in the
* buffer (i.e. %dccpap_buf_head)
* @dccpap_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
* by the buffer with State 0
*
* Additionally, the HC-Receiver must keep some information about the
* Ack Vectors it has recently sent. For each packet sent carrying an
* Ack Vector, it remembers four variables:
*
* @dccpap_ack_seqno - the Sequence Number used for the packet
* (HC-Receiver seqno)
* @dccpap_ack_ptr - the value of buf_head at the time of acknowledgement.
* @dccpap_ack_ackno - the Acknowledgement Number used for the packet
* (HC-Sender seqno)
* @dccpap_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
*
* @dccpap_buf_len - circular buffer length
* @dccpap_time - the time in usecs
* @dccpap_buf - circular buffer of acknowledgeable packets
*/
struct dccp_ackpkts {
unsigned int dccpap_buf_head;
unsigned int dccpap_buf_tail;
u64 dccpap_buf_ackno;
u64 dccpap_ack_seqno;
u64 dccpap_ack_ackno;
unsigned int dccpap_ack_ptr;
unsigned int dccpap_buf_vector_len;
unsigned int dccpap_ack_vector_len;
unsigned int dccpap_buf_len;
struct timeval dccpap_time;
u8 dccpap_buf_nonce;
u8 dccpap_ack_nonce;
u8 dccpap_buf[0];
};
extern struct dccp_ackpkts *
dccp_ackpkts_alloc(unsigned int len,
const unsigned int __nocast priority);
extern void dccp_ackpkts_free(struct dccp_ackpkts *ap);
extern int dccp_ackpkts_add(struct dccp_ackpkts *ap, const struct sock *sk,
u64 ackno, u8 state);
extern void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap,
struct sock *sk, u64 ackno);
extern void dccp_timestamp(const struct sock *sk, struct timeval *tv);
static inline suseconds_t timeval_usecs(const struct timeval *tv)
@ -470,15 +423,4 @@ static inline void timeval_sub_usecs(struct timeval *tv,
}
}
#ifdef CONFIG_IP_DCCP_DEBUG
extern void dccp_ackvector_print(const u64 ackno,
const unsigned char *vector, int len);
extern void dccp_ackpkts_print(const struct dccp_ackpkts *ap);
#else
static inline void dccp_ackvector_print(const u64 ackno,
const unsigned char *vector,
int len) { }
static inline void dccp_ackpkts_print(const struct dccp_ackpkts *ap) { }
#endif
#endif /* _DCCP_H */

69
net/dccp/input.c
View File

@ -16,6 +16,7 @@
#include <net/sock.h>
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
@ -60,8 +61,8 @@ static inline void dccp_event_ack_recv(struct sock *sk, struct sk_buff *skb)
struct dccp_sock *dp = dccp_sk(sk);
if (dp->dccps_options.dccpo_send_ack_vector)
dccp_ackpkts_check_rcv_ackno(dp->dccps_hc_rx_ackpkts, sk,
DCCP_SKB_CB(skb)->dccpd_ack_seq);
dccp_ackvec_check_rcv_ackno(dp->dccps_hc_rx_ackvec, sk,
DCCP_SKB_CB(skb)->dccpd_ack_seq);
}
static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb)
@ -164,37 +165,11 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
dccp_event_ack_recv(sk, skb);
/*
* FIXME: check ECN to see if we should use
* DCCP_ACKPKTS_STATE_ECN_MARKED
*/
if (dp->dccps_options.dccpo_send_ack_vector) {
struct dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
if (dccp_ackpkts_add(dp->dccps_hc_rx_ackpkts, sk,
DCCP_SKB_CB(skb)->dccpd_seq,
DCCP_ACKPKTS_STATE_RECEIVED)) {
LIMIT_NETDEBUG(KERN_WARNING "DCCP: acknowledgeable "
"packets buffer full!\n");
ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
inet_csk_schedule_ack(sk);
inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
TCP_DELACK_MIN,
DCCP_RTO_MAX);
goto discard;
}
/*
* FIXME: this activation is probably wrong, have to study more
* TCP delack machinery and how it fits into DCCP draft, but
* for now it kinda "works" 8)
*/
if (!inet_csk_ack_scheduled(sk)) {
inet_csk_schedule_ack(sk);
inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, 5 * HZ,
DCCP_RTO_MAX);
}
}
if (dp->dccps_options.dccpo_send_ack_vector &&
dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
DCCP_SKB_CB(skb)->dccpd_seq,
DCCP_ACKVEC_STATE_RECEIVED))
goto discard;
ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
@ -495,29 +470,11 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
/*
* FIXME: check ECN to see if we should use
* DCCP_ACKPKTS_STATE_ECN_MARKED
*/
if (dp->dccps_options.dccpo_send_ack_vector) {
if (dccp_ackpkts_add(dp->dccps_hc_rx_ackpkts, sk,
dcb->dccpd_seq,
DCCP_ACKPKTS_STATE_RECEIVED))
goto discard;
/*
* FIXME: this activation is probably wrong, have to
* study more TCP delack machinery and how it fits into
* DCCP draft, but for now it kinda "works" 8)
*/
if ((dp->dccps_hc_rx_ackpkts->dccpap_ack_seqno ==
DCCP_MAX_SEQNO + 1) &&
!inet_csk_ack_scheduled(sk)) {
inet_csk_schedule_ack(sk);
inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
TCP_DELACK_MIN,
DCCP_RTO_MAX);
}
}
if (dp->dccps_options.dccpo_send_ack_vector &&
dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
DCCP_SKB_CB(skb)->dccpd_seq,
DCCP_ACKVEC_STATE_RECEIVED))
goto discard;
}
/*

59
net/dccp/ipv4.c
View File

@ -23,6 +23,7 @@
#include <net/tcp_states.h>
#include <net/xfrm.h>
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
@ -1112,45 +1113,7 @@ int dccp_v4_rcv(struct sk_buff *skb)
goto discard_it;
dh = dccp_hdr(skb);
#if 0
/*
* Use something like this to simulate some DATA/DATAACK loss to test
* dccp_ackpkts_add, you'll get something like this on a session that
* sends 10 DATA/DATAACK packets:
*
* ackpkts_print: 281473596467422 |0,0|3,0|0,0|3,0|0,0|3,0|0,0|3,0|0,1|
*
* 0, 0 means: DCCP_ACKPKTS_STATE_RECEIVED, RLE == just this packet
* 0, 1 means: DCCP_ACKPKTS_STATE_RECEIVED, RLE == two adjacent packets
* with the same state
* 3, 0 means: DCCP_ACKPKTS_STATE_NOT_RECEIVED, RLE == just this packet
*
* So...
*
* 281473596467422 was received
* 281473596467421 was not received
* 281473596467420 was received
* 281473596467419 was not received
* 281473596467418 was received
* 281473596467417 was not received
* 281473596467416 was received
* 281473596467415 was not received
* 281473596467414 was received
* 281473596467413 was received (this one was the 3way handshake
* RESPONSE)
*
*/
if (dh->dccph_type == DCCP_PKT_DATA ||
dh->dccph_type == DCCP_PKT_DATAACK) {
static int discard = 0;
if (discard) {
discard = 0;
goto discard_it;
}
discard = 1;
}
#endif
DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb);
DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
@ -1264,11 +1227,9 @@ static int dccp_v4_init_sock(struct sock *sk)
do_gettimeofday(&dp->dccps_epoch);
if (dp->dccps_options.dccpo_send_ack_vector) {
dp->dccps_hc_rx_ackpkts =
dccp_ackpkts_alloc(DCCP_MAX_ACK_VECTOR_LEN,
GFP_KERNEL);
if (dp->dccps_hc_rx_ackpkts == NULL)
dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(DCCP_MAX_ACKVEC_LEN,
GFP_KERNEL);
if (dp->dccps_hc_rx_ackvec == NULL)
return -ENOMEM;
}
@ -1288,8 +1249,10 @@ static int dccp_v4_init_sock(struct sock *sk)
dp->dccps_hc_tx_ccid == NULL) {
ccid_exit(dp->dccps_hc_rx_ccid, sk);
ccid_exit(dp->dccps_hc_tx_ccid, sk);
dccp_ackpkts_free(dp->dccps_hc_rx_ackpkts);
dp->dccps_hc_rx_ackpkts = NULL;
if (dp->dccps_options.dccpo_send_ack_vector) {
dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
dp->dccps_hc_rx_ackvec = NULL;
}
dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
return -ENOMEM;
}
@ -1331,8 +1294,10 @@ static int dccp_v4_destroy_sock(struct sock *sk)
ccid_hc_rx_exit(dp->dccps_hc_rx_ccid, sk);
ccid_hc_tx_exit(dp->dccps_hc_tx_ccid, sk);
dccp_ackpkts_free(dp->dccps_hc_rx_ackpkts);
dp->dccps_hc_rx_ackpkts = NULL;
if (dp->dccps_options.dccpo_send_ack_vector) {
dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
dp->dccps_hc_rx_ackvec = NULL;
}
ccid_exit(dp->dccps_hc_rx_ccid, sk);
ccid_exit(dp->dccps_hc_tx_ccid, sk);
dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;

13
net/dccp/minisocks.c
View File

@ -19,6 +19,7 @@
#include <net/xfrm.h>
#include <net/inet_timewait_sock.h>
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
@ -94,23 +95,23 @@ struct sock *dccp_create_openreq_child(struct sock *sk,
struct dccp_sock *newdp = dccp_sk(newsk);
newdp->dccps_role = DCCP_ROLE_SERVER;
newdp->dccps_hc_rx_ackpkts = NULL;
newdp->dccps_hc_rx_ackvec = NULL;
newdp->dccps_service_list = NULL;
newdp->dccps_service = dreq->dreq_service;
newicsk->icsk_rto = DCCP_TIMEOUT_INIT;
do_gettimeofday(&newdp->dccps_epoch);
if (newdp->dccps_options.dccpo_send_ack_vector) {
newdp->dccps_hc_rx_ackpkts =
dccp_ackpkts_alloc(DCCP_MAX_ACK_VECTOR_LEN,
GFP_ATOMIC);
newdp->dccps_hc_rx_ackvec =
dccp_ackvec_alloc(DCCP_MAX_ACKVEC_LEN,
GFP_ATOMIC);
/*
* XXX: We're using the same CCIDs set on the parent,
* i.e. sk_clone copied the master sock and left the
* CCID pointers for this child, that is why we do the
* __ccid_get calls.
*/
if (unlikely(newdp->dccps_hc_rx_ackpkts == NULL))
if (unlikely(newdp->dccps_hc_rx_ackvec == NULL))
goto out_free;
}
@ -118,7 +119,7 @@ struct sock *dccp_create_openreq_child(struct sock *sk,
newsk) != 0 ||
ccid_hc_tx_init(newdp->dccps_hc_tx_ccid,
newsk) != 0)) {
dccp_ackpkts_free(newdp->dccps_hc_rx_ackpkts);
dccp_ackvec_free(newdp->dccps_hc_rx_ackvec);
ccid_hc_rx_exit(newdp->dccps_hc_rx_ccid, newsk);
ccid_hc_tx_exit(newdp->dccps_hc_tx_ccid, newsk);
out_free:

440
net/dccp/options.c
View File

@ -18,15 +18,10 @@
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
struct sock *sk,
const u64 ackno,
const unsigned char len,
const unsigned char *vector);
/* 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,
@ -113,25 +108,13 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
opt_recv->dccpor_ndp);
break;
case DCCPO_ACK_VECTOR_0:
if (len > DCCP_MAX_ACK_VECTOR_LEN)
goto out_invalid_option;
case DCCPO_ACK_VECTOR_1:
if (pkt_type == DCCP_PKT_DATA)
continue;
opt_recv->dccpor_ack_vector_len = len;
opt_recv->dccpor_ack_vector_idx = value - options;
dccp_pr_debug("%sACK vector 0, len=%d, ack_ackno=%llu\n",
debug_prefix, len,
(unsigned long long)
DCCP_SKB_CB(skb)->dccpd_ack_seq);
dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq,
value, len);
dccp_ackpkts_check_rcv_ackvector(dp->dccps_hc_rx_ackpkts,
sk,
DCCP_SKB_CB(skb)->dccpd_ack_seq,
len, value);
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)
@ -352,86 +335,6 @@ void dccp_insert_option_elapsed_time(struct sock *sk,
EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);
static void dccp_insert_option_ack_vector(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 dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
int len = ap->dccpap_buf_vector_len + 2;
struct timeval now;
u32 elapsed_time;
unsigned char *to, *from;
dccp_timestamp(sk, &now);
elapsed_time = timeval_delta(&now, &ap->dccpap_time) / 10;
if (elapsed_time != 0)
dccp_insert_option_elapsed_time(sk, skb, elapsed_time);
if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to "
"insert ACK Vector!\n");
return;
}
/*
* XXX: now we have just one ack vector sent record, so
* we have to wait for it to be cleared.
*
* Of course this is not acceptable, but this is just for
* basic testing now.
*/
if (ap->dccpap_ack_seqno != DCCP_MAX_SEQNO + 1)
return;
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
to = skb_push(skb, len);
*to++ = DCCPO_ACK_VECTOR_0;
*to++ = len;
len = ap->dccpap_buf_vector_len;
from = ap->dccpap_buf + ap->dccpap_buf_head;
/* Check if buf_head wraps */
if (ap->dccpap_buf_head + len > ap->dccpap_buf_len) {
const unsigned int tailsize = (ap->dccpap_buf_len -
ap->dccpap_buf_head);
memcpy(to, from, tailsize);
to += tailsize;
len -= tailsize;
from = ap->dccpap_buf;
}
memcpy(to, from, len);
/*
* From draft-ietf-dccp-spec-11.txt:
*
* For each acknowledgement it sends, the HC-Receiver will add an
* acknowledgement record. ack_seqno will equal the HC-Receiver
* sequence number it used for the ack packet; ack_ptr will equal
* buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
* equal buf_nonce.
*
* This implemention uses just one ack record for now.
*/
ap->dccpap_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
ap->dccpap_ack_ptr = ap->dccpap_buf_head;
ap->dccpap_ack_ackno = ap->dccpap_buf_ackno;
ap->dccpap_ack_nonce = ap->dccpap_buf_nonce;
ap->dccpap_ack_vector_len = ap->dccpap_buf_vector_len;
dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
"ack_ackno=%llu\n",
debug_prefix, ap->dccpap_ack_vector_len,
(unsigned long long) ap->dccpap_ack_seqno,
(unsigned long long) ap->dccpap_ack_ackno);
}
void dccp_timestamp(const struct sock *sk, struct timeval *tv)
{
const struct dccp_sock *dp = dccp_sk(sk);
@ -528,9 +431,8 @@ void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
if (!dccp_packet_without_ack(skb)) {
if (dp->dccps_options.dccpo_send_ack_vector &&
(dp->dccps_hc_rx_ackpkts->dccpap_buf_ackno !=
DCCP_MAX_SEQNO + 1))
dccp_insert_option_ack_vector(sk, skb);
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);
}
@ -557,331 +459,3 @@ void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
}
}
}
struct dccp_ackpkts *dccp_ackpkts_alloc(const unsigned int len,
const unsigned int __nocast priority)
{
struct dccp_ackpkts *ap = kmalloc(sizeof(*ap) + len, priority);
if (ap != NULL) {
#ifdef CONFIG_IP_DCCP_DEBUG
memset(ap->dccpap_buf, 0xFF, len);
#endif
ap->dccpap_buf_len = len;
ap->dccpap_buf_head =
ap->dccpap_buf_tail =
ap->dccpap_buf_len - 1;
ap->dccpap_buf_ackno =
ap->dccpap_ack_ackno =
ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
ap->dccpap_buf_nonce = ap->dccpap_buf_nonce = 0;
ap->dccpap_ack_ptr = 0;
ap->dccpap_time.tv_sec = 0;
ap->dccpap_time.tv_usec = 0;
ap->dccpap_buf_vector_len = ap->dccpap_ack_vector_len = 0;
}
return ap;
}
void dccp_ackpkts_free(struct dccp_ackpkts *ap)
{
if (ap != NULL) {
#ifdef CONFIG_IP_DCCP_DEBUG
memset(ap, 0xFF, sizeof(*ap) + ap->dccpap_buf_len);
#endif
kfree(ap);
}
}
static inline u8 dccp_ackpkts_state(const struct dccp_ackpkts *ap,
const unsigned int index)
{
return ap->dccpap_buf[index] & DCCP_ACKPKTS_STATE_MASK;
}
static inline u8 dccp_ackpkts_len(const struct dccp_ackpkts *ap,
const unsigned int index)
{
return ap->dccpap_buf[index] & DCCP_ACKPKTS_LEN_MASK;
}
/*
* If several packets are missing, the HC-Receiver may prefer to enter multiple
* bytes with run length 0, rather than a single byte with a larger run length;
* this simplifies table updates if one of the missing packets arrives.
*/
static inline int dccp_ackpkts_set_buf_head_state(struct dccp_ackpkts *ap,
const unsigned int packets,
const unsigned char state)
{
unsigned int gap;
signed long new_head;
if (ap->dccpap_buf_vector_len + packets > ap->dccpap_buf_len)
return -ENOBUFS;
gap = packets - 1;
new_head = ap->dccpap_buf_head - packets;
if (new_head < 0) {
if (gap > 0) {
memset(ap->dccpap_buf, DCCP_ACKPKTS_STATE_NOT_RECEIVED,
gap + new_head + 1);
gap = -new_head;
}
new_head += ap->dccpap_buf_len;
}
ap->dccpap_buf_head = new_head;
if (gap > 0)
memset(ap->dccpap_buf + ap->dccpap_buf_head + 1,
DCCP_ACKPKTS_STATE_NOT_RECEIVED, gap);
ap->dccpap_buf[ap->dccpap_buf_head] = state;
ap->dccpap_buf_vector_len += packets;
return 0;
}
/*
* Implements the draft-ietf-dccp-spec-11.txt Appendix A
*/
int dccp_ackpkts_add(struct dccp_ackpkts *ap, const struct sock *sk,
u64 ackno, u8 state)
{
/*
* Check at the right places if the buffer is full, if it is, tell the
* caller to start dropping packets till the HC-Sender acks our ACK
* vectors, when we will free up space in dccpap_buf.
*
* We may well decide to do buffer compression, etc, but for now lets
* just drop.
*
* From Appendix A:
*
* Of course, the circular buffer may overflow, either when the
* HC-Sender is sending data at a very high rate, when the
* HC-Receiver's acknowledgements are not reaching the HC-Sender,
* or when the HC-Sender is forgetting to acknowledge those acks
* (so the HC-Receiver is unable to clean up old state). In this
* case, the HC-Receiver should either compress the buffer (by
* increasing run lengths when possible), transfer its state to
* a larger buffer, or, as a last resort, drop all received
* packets, without processing them whatsoever, until its buffer
* shrinks again.
*/
/* See if this is the first ackno being inserted */
if (ap->dccpap_buf_vector_len == 0) {
ap->dccpap_buf[ap->dccpap_buf_head] = state;
ap->dccpap_buf_vector_len = 1;
} else if (after48(ackno, ap->dccpap_buf_ackno)) {
const u64 delta = dccp_delta_seqno(ap->dccpap_buf_ackno,
ackno);
/*
* Look if the state of this packet is the same as the
* previous ackno and if so if we can bump the head len.
*/
if (delta == 1 &&
dccp_ackpkts_state(ap, ap->dccpap_buf_head) == state &&
(dccp_ackpkts_len(ap, ap->dccpap_buf_head) <
DCCP_ACKPKTS_LEN_MASK))
ap->dccpap_buf[ap->dccpap_buf_head]++;
else if (dccp_ackpkts_set_buf_head_state(ap, delta, state))
return -ENOBUFS;
} else {
/*
* A.1.2. Old Packets
*
* When a packet with Sequence Number S arrives, and
* S <= buf_ackno, the HC-Receiver will scan the table
* for the byte corresponding to S. (Indexing structures
* could reduce the complexity of this scan.)
*/
u64 delta = dccp_delta_seqno(ackno, ap->dccpap_buf_ackno);
unsigned int index = ap->dccpap_buf_head;
while (1) {
const u8 len = dccp_ackpkts_len(ap, index);
const u8 state = dccp_ackpkts_state(ap, index);
/*
* valid packets not yet in dccpap_buf have a reserved
* entry, with a len equal to 0.
*/
if (state == DCCP_ACKPKTS_STATE_NOT_RECEIVED &&
len == 0 && delta == 0) { /* Found our
reserved seat! */
dccp_pr_debug("Found %llu reserved seat!\n",
(unsigned long long) ackno);
ap->dccpap_buf[index] = state;
goto out;
}
/* len == 0 means one packet */
if (delta < len + 1)
goto out_duplicate;
delta -= len + 1;
if (++index == ap->dccpap_buf_len)
index = 0;
}
}
ap->dccpap_buf_ackno = ackno;
dccp_timestamp(sk, &ap->dccpap_time);
out:
dccp_pr_debug("");
dccp_ackpkts_print(ap);
return 0;
out_duplicate:
/* Duplicate packet */
dccp_pr_debug("Received a dup or already considered lost "
"packet: %llu\n", (unsigned long long) ackno);
return -EILSEQ;
}
#ifdef CONFIG_IP_DCCP_DEBUG
void dccp_ackvector_print(const u64 ackno, const unsigned char *vector,
int len)
{
if (!dccp_debug)
return;
printk("ACK vector len=%d, ackno=%llu |", len,
(unsigned long long) ackno);
while (len--) {
const u8 state = (*vector & DCCP_ACKPKTS_STATE_MASK) >> 6;
const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
printk("%d,%d|", state, rl);
++vector;
}
printk("\n");
}
void dccp_ackpkts_print(const struct dccp_ackpkts *ap)
{
dccp_ackvector_print(ap->dccpap_buf_ackno,
ap->dccpap_buf + ap->dccpap_buf_head,
ap->dccpap_buf_vector_len);
}
#endif
static void dccp_ackpkts_trow_away_ack_record(struct dccp_ackpkts *ap)
{
/*
* As we're keeping track of the ack vector size
* (dccpap_buf_vector_len) and the sent ack vector size
* (dccpap_ack_vector_len) we don't need dccpap_buf_tail at all, but
* keep this code here as in the future we'll implement a vector of
* ack records, as suggested in draft-ietf-dccp-spec-11.txt
* Appendix A. -acme
*/
#if 0
ap->dccpap_buf_tail = ap->dccpap_ack_ptr + 1;
if (ap->dccpap_buf_tail >= ap->dccpap_buf_len)
ap->dccpap_buf_tail -= ap->dccpap_buf_len;
#endif
ap->dccpap_buf_vector_len -= ap->dccpap_ack_vector_len;
}
void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap, struct sock *sk,
u64 ackno)
{
/* Check if we actually sent an ACK vector */
if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
return;
if (ackno == ap->dccpap_ack_seqno) {
#ifdef CONFIG_IP_DCCP_DEBUG
struct dccp_sock *dp = dccp_sk(sk);
const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
"CLIENT rx ack: " : "server rx ack: ";
#endif
dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "
"ack_ackno=%llu, ACKED!\n",
debug_prefix, 1,
(unsigned long long) ap->dccpap_ack_seqno,
(unsigned long long) ap->dccpap_ack_ackno);
dccp_ackpkts_trow_away_ack_record(ap);
ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
}
}
static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
struct sock *sk, u64 ackno,
const unsigned char len,
const unsigned char *vector)
{
unsigned char i;
/* Check if we actually sent an ACK vector */
if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
return;
/*
* We're in the receiver half connection, so if the received an ACK
* vector ackno (e.g. 50) before dccpap_ack_seqno (e.g. 52), we're
* not interested.
*
* Extra explanation with example:
*
* if we received an ACK vector with ackno 50, it can only be acking
* 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent).
*/
/* dccp_pr_debug("is %llu < %llu? ", ackno, ap->dccpap_ack_seqno); */
if (before48(ackno, ap->dccpap_ack_seqno)) {
/* dccp_pr_debug_cat("yes\n"); */
return;
}
/* dccp_pr_debug_cat("no\n"); */
i = len;
while (i--) {
const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
u64 ackno_end_rl;
dccp_set_seqno(&ackno_end_rl, ackno - rl);
/*
* dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl,
* ap->dccpap_ack_seqno, ackno);
*/
if (between48(ap->dccpap_ack_seqno, ackno_end_rl, ackno)) {
const u8 state = (*vector &
DCCP_ACKPKTS_STATE_MASK) >> 6;
/* dccp_pr_debug_cat("yes\n"); */
if (state != DCCP_ACKPKTS_STATE_NOT_RECEIVED) {
#ifdef CONFIG_IP_DCCP_DEBUG
struct dccp_sock *dp = dccp_sk(sk);
const char *debug_prefix =
dp->dccps_role == DCCP_ROLE_CLIENT ?
"CLIENT rx ack: " : "server rx ack: ";
#endif
dccp_pr_debug("%sACK vector 0, len=%d, "
"ack_seqno=%llu, ack_ackno=%llu, "
"ACKED!\n",
debug_prefix, len,
(unsigned long long)
ap->dccpap_ack_seqno,
(unsigned long long)
ap->dccpap_ack_ackno);
dccp_ackpkts_trow_away_ack_record(ap);
}
/*
* If dccpap_ack_seqno was not received, no problem
* we'll send another ACK vector.
*/
ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
break;
}
/* dccp_pr_debug_cat("no\n"); */
dccp_set_seqno(&ackno, ackno_end_rl - 1);
++vector;
}
}

12
net/dccp/output.c
View File

@ -16,6 +16,7 @@
#include <net/sock.h>
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
@ -225,7 +226,6 @@ int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo)
err = dccp_wait_for_ccid(sk, skb, timeo);
if (err == 0) {
const struct dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
const int len = skb->len;
@ -236,15 +236,7 @@ int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo)
inet_csk(sk)->icsk_rto,
DCCP_RTO_MAX);
dcb->dccpd_type = DCCP_PKT_DATAACK;
/*
* FIXME: we really should have a
* dccps_ack_pending or use icsk.
*/
} else if (inet_csk_ack_scheduled(sk) ||
dp->dccps_timestamp_echo != 0 ||
(dp->dccps_options.dccpo_send_ack_vector &&
ap->dccpap_buf_ackno != DCCP_MAX_SEQNO + 1 &&
ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1))
} else if (dccp_ack_pending(sk))
dcb->dccpd_type = DCCP_PKT_DATAACK;
else
dcb->dccpd_type = DCCP_PKT_DATA;