提交 afe00251 编写于 作者: A Andrea Bittau 提交者: David S. Miller

[DCCP]: Initial feature negotiation implementation

Still needs more work, but boots and doesn't crashes, even
does some negotiation!

18:38:52.174934  127.0.0.1.43458 > 127.0.0.1.5001: request <change_l ack_ratio 2, change_r ccid 2, change_l ccid 2>
18:38:52.218526  127.0.0.1.5001 > 127.0.0.1.43458: response <nop, nop, change_l ack_ratio 2, confirm_r ccid 2 2, confirm_l ccid 2 2, confirm_r ack_ratio 2>
18:38:52.185398  127.0.0.1.43458 > 127.0.0.1.5001: <nop, confirm_r ack_ratio 2, ack_vector0 0x00, elapsed_time 212>

:-)
Signed-off-by: NAndrea Bittau <a.bittau@cs.ucl.ac.uk>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
上级 2a91aa39
......@@ -154,6 +154,10 @@ enum {
DCCPO_MANDATORY = 1,
DCCPO_MIN_RESERVED = 3,
DCCPO_MAX_RESERVED = 31,
DCCPO_CHANGE_L = 32,
DCCPO_CONFIRM_L = 33,
DCCPO_CHANGE_R = 34,
DCCPO_CONFIRM_R = 35,
DCCPO_NDP_COUNT = 37,
DCCPO_ACK_VECTOR_0 = 38,
DCCPO_ACK_VECTOR_1 = 39,
......@@ -168,7 +172,9 @@ enum {
/* DCCP features */
enum {
DCCPF_RESERVED = 0,
DCCPF_CCID = 1,
DCCPF_SEQUENCE_WINDOW = 3,
DCCPF_ACK_RATIO = 5,
DCCPF_SEND_ACK_VECTOR = 6,
DCCPF_SEND_NDP_COUNT = 7,
/* 10-127 reserved */
......@@ -176,9 +182,18 @@ enum {
DCCPF_MAX_CCID_SPECIFIC = 255,
};
/* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
struct dccp_so_feat {
__u8 dccpsf_feat;
__u8 *dccpsf_val;
__u8 dccpsf_len;
};
/* DCCP socket options */
#define DCCP_SOCKOPT_PACKET_SIZE 1
#define DCCP_SOCKOPT_SERVICE 2
#define DCCP_SOCKOPT_CHANGE_L 3
#define DCCP_SOCKOPT_CHANGE_R 4
#define DCCP_SOCKOPT_CCID_RX_INFO 128
#define DCCP_SOCKOPT_CCID_TX_INFO 192
......@@ -314,8 +329,8 @@ static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
/* initial values for each feature */
#define DCCPF_INITIAL_SEQUENCE_WINDOW 100
/* FIXME: for now we're using CCID 2 (TCP-Like) */
#define DCCPF_INITIAL_CCID 2
#define DCCPF_INITIAL_ACK_RATIO 2
#define DCCPF_INITIAL_SEND_ACK_VECTOR 1
/* FIXME: for now we're default to 1 but it should really be 0 */
#define DCCPF_INITIAL_SEND_NDP_COUNT 1
......@@ -335,6 +350,24 @@ struct dccp_options {
__u8 dccpo_tx_ccid;
__u8 dccpo_send_ack_vector;
__u8 dccpo_send_ndp_count;
__u8 dccpo_ack_ratio;
struct list_head dccpo_pending;
struct list_head dccpo_conf;
};
struct dccp_opt_conf {
__u8 *dccpoc_val;
__u8 dccpoc_len;
};
struct dccp_opt_pend {
struct list_head dccpop_node;
__u8 dccpop_type;
__u8 dccpop_feat;
__u8 *dccpop_val;
__u8 dccpop_len;
int dccpop_conf;
struct dccp_opt_conf *dccpop_sc;
};
extern void __dccp_options_init(struct dccp_options *dccpo);
......
......@@ -4,7 +4,7 @@ dccp_ipv6-y := ipv6.o
obj-$(CONFIG_IP_DCCP) += dccp.o
dccp-y := ccid.o input.o ipv4.o minisocks.o options.o output.o proto.o \
dccp-y := ccid.o feat.o input.o ipv4.o minisocks.o options.o output.o proto.o \
timer.o
dccp-$(CONFIG_IP_DCCP_ACKVEC) += ackvec.o
......
/*
* net/dccp/feat.c
*
* An implementation of the DCCP protocol
* Andrea Bittau <a.bittau@cs.ucl.ac.uk>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/config.h>
#include <linux/module.h>
#include "dccp.h"
#include "feat.h"
#define DCCP_FEAT_SP_NOAGREE (-123)
int dccp_feat_change(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len,
gfp_t gfp)
{
struct dccp_sock *dp = dccp_sk(sk);
struct dccp_opt_pend *opt;
dccp_pr_debug("feat change type=%d feat=%d\n", type, feature);
/* check if that feature is already being negotiated */
list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
dccpop_node) {
/* ok we found a negotiation for this option already */
if (opt->dccpop_feat == feature && opt->dccpop_type == type) {
dccp_pr_debug("Replacing old\n");
/* replace */
BUG_ON(opt->dccpop_val == NULL);
kfree(opt->dccpop_val);
opt->dccpop_val = val;
opt->dccpop_len = len;
opt->dccpop_conf = 0;
return 0;
}
}
/* negotiation for a new feature */
opt = kmalloc(sizeof(*opt), gfp);
if (opt == NULL)
return -ENOMEM;
opt->dccpop_type = type;
opt->dccpop_feat = feature;
opt->dccpop_len = len;
opt->dccpop_val = val;
opt->dccpop_conf = 0;
opt->dccpop_sc = NULL;
BUG_ON(opt->dccpop_val == NULL);
list_add_tail(&opt->dccpop_node, &dp->dccps_options.dccpo_pending);
return 0;
}
EXPORT_SYMBOL_GPL(dccp_feat_change);
/* XXX taking only u8 vals */
static int dccp_feat_update(struct sock *sk, u8 type, u8 feat, u8 val)
{
/* FIXME implement */
dccp_pr_debug("changing [%d] feat %d to %d\n", type, feat, val);
return 0;
}
static int dccp_feat_reconcile(struct sock *sk, struct dccp_opt_pend *opt,
u8 *rpref, u8 rlen)
{
struct dccp_sock *dp = dccp_sk(sk);
u8 *spref, slen, *res = NULL;
int i, j, rc, agree = 1;
BUG_ON(rpref == NULL);
/* check if we are the black sheep */
if (dp->dccps_role == DCCP_ROLE_CLIENT) {
spref = rpref;
slen = rlen;
rpref = opt->dccpop_val;
rlen = opt->dccpop_len;
} else {
spref = opt->dccpop_val;
slen = opt->dccpop_len;
}
/*
* Now we have server preference list in spref and client preference in
* rpref
*/
BUG_ON(spref == NULL);
BUG_ON(rpref == NULL);
/* FIXME sanity check vals */
/* Are values in any order? XXX Lame "algorithm" here */
/* XXX assume values are 1 byte */
for (i = 0; i < slen; i++) {
for (j = 0; j < rlen; j++) {
if (spref[i] == rpref[j]) {
res = &spref[i];
break;
}
}
if (res)
break;
}
/* we didn't agree on anything */
if (res == NULL) {
/* confirm previous value */
switch (opt->dccpop_feat) {
case DCCPF_CCID:
/* XXX did i get this right? =P */
if (opt->dccpop_type == DCCPO_CHANGE_L)
res = &dp->dccps_options.dccpo_tx_ccid;
else
res = &dp->dccps_options.dccpo_rx_ccid;
break;
default:
WARN_ON(1); /* XXX implement res */
return -EFAULT;
}
dccp_pr_debug("Don't agree... reconfirming %d\n", *res);
agree = 0; /* this is used for mandatory options... */
}
/* need to put result and our preference list */
/* XXX assume 1 byte vals */
rlen = 1 + opt->dccpop_len;
rpref = kmalloc(rlen, GFP_ATOMIC);
if (rpref == NULL)
return -ENOMEM;
*rpref = *res;
memcpy(&rpref[1], opt->dccpop_val, opt->dccpop_len);
/* put it in the "confirm queue" */
if (opt->dccpop_sc == NULL) {
opt->dccpop_sc = kmalloc(sizeof(*opt->dccpop_sc), GFP_ATOMIC);
if (opt->dccpop_sc == NULL) {
kfree(rpref);
return -ENOMEM;
}
} else {
/* recycle the confirm slot */
BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
kfree(opt->dccpop_sc->dccpoc_val);
dccp_pr_debug("recycling confirm slot\n");
}
memset(opt->dccpop_sc, 0, sizeof(*opt->dccpop_sc));
opt->dccpop_sc->dccpoc_val = rpref;
opt->dccpop_sc->dccpoc_len = rlen;
/* update the option on our side [we are about to send the confirm] */
rc = dccp_feat_update(sk, opt->dccpop_type, opt->dccpop_feat, *res);
if (rc) {
kfree(opt->dccpop_sc->dccpoc_val);
kfree(opt->dccpop_sc);
opt->dccpop_sc = 0;
return rc;
}
dccp_pr_debug("Will confirm %d\n", *rpref);
/* say we want to change to X but we just got a confirm X, suppress our
* change
*/
if (!opt->dccpop_conf) {
if (*opt->dccpop_val == *res)
opt->dccpop_conf = 1;
dccp_pr_debug("won't ask for change of same feature\n");
}
return agree ? 0 : DCCP_FEAT_SP_NOAGREE; /* used for mandatory opts */
}
static int dccp_feat_sp(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
{
struct dccp_sock *dp = dccp_sk(sk);
struct dccp_opt_pend *opt;
int rc = 1;
u8 t;
/*
* We received a CHANGE. We gotta match it against our own preference
* list. If we got a CHANGE_R it means it's a change for us, so we need
* to compare our CHANGE_L list.
*/
if (type == DCCPO_CHANGE_L)
t = DCCPO_CHANGE_R;
else
t = DCCPO_CHANGE_L;
/* find our preference list for this feature */
list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
dccpop_node) {
if (opt->dccpop_type != t || opt->dccpop_feat != feature)
continue;
/* find the winner from the two preference lists */
rc = dccp_feat_reconcile(sk, opt, val, len);
break;
}
/* We didn't deal with the change. This can happen if we have no
* preference list for the feature. In fact, it just shouldn't
* happen---if we understand a feature, we should have a preference list
* with at least the default value.
*/
BUG_ON(rc == 1);
return rc;
}
static int dccp_feat_nn(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
{
struct dccp_opt_pend *opt;
struct dccp_sock *dp = dccp_sk(sk);
u8 *copy;
int rc;
/* NN features must be change L */
if (type == DCCPO_CHANGE_R) {
dccp_pr_debug("received CHANGE_R %d for NN feat %d\n",
type, feature);
return -EFAULT;
}
/* XXX sanity check opt val */
/* copy option so we can confirm it */
opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
if (opt == NULL)
return -ENOMEM;
copy = kmalloc(len, GFP_ATOMIC);
if (copy == NULL) {
kfree(opt);
return -ENOMEM;
}
memcpy(copy, val, len);
opt->dccpop_type = DCCPO_CONFIRM_R; /* NN can only confirm R */
opt->dccpop_feat = feature;
opt->dccpop_val = copy;
opt->dccpop_len = len;
/* change feature */
rc = dccp_feat_update(sk, type, feature, *val);
if (rc) {
kfree(opt->dccpop_val);
kfree(opt);
return rc;
}
dccp_pr_debug("Confirming NN feature %d (val=%d)\n", feature, *copy);
list_add_tail(&opt->dccpop_node, &dp->dccps_options.dccpo_conf);
return 0;
}
static void dccp_feat_empty_confirm(struct sock *sk, u8 type, u8 feature)
{
struct dccp_sock *dp = dccp_sk(sk);
/* XXX check if other confirms for that are queued and recycle slot */
struct dccp_opt_pend *opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
if (opt == NULL) {
/* XXX what do we do? Ignoring should be fine. It's a change
* after all =P
*/
return;
}
opt->dccpop_type = type == DCCPO_CHANGE_L ? DCCPO_CONFIRM_R :
DCCPO_CONFIRM_L;
opt->dccpop_feat = feature;
opt->dccpop_val = 0;
opt->dccpop_len = 0;
/* change feature */
dccp_pr_debug("Empty confirm feature %d type %d\n", feature, type);
list_add_tail(&opt->dccpop_node, &dp->dccps_options.dccpo_conf);
}
static void dccp_feat_flush_confirm(struct sock *sk)
{
struct dccp_sock *dp = dccp_sk(sk);
/* Check if there is anything to confirm in the first place */
int yes = !list_empty(&dp->dccps_options.dccpo_conf);
if (!yes) {
struct dccp_opt_pend *opt;
list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
dccpop_node) {
if (opt->dccpop_conf) {
yes = 1;
break;
}
}
}
if (!yes)
return;
/* OK there is something to confirm... */
/* XXX check if packet is in flight? Send delayed ack?? */
if (sk->sk_state == DCCP_OPEN)
dccp_send_ack(sk);
}
int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
{
int rc;
dccp_pr_debug("got feat change type=%d feat=%d\n", type, feature);
/* figure out if it's SP or NN feature */
switch (feature) {
/* deal with SP features */
case DCCPF_CCID:
rc = dccp_feat_sp(sk, type, feature, val, len);
break;
/* deal with NN features */
case DCCPF_ACK_RATIO:
rc = dccp_feat_nn(sk, type, feature, val, len);
break;
/* XXX implement other features */
default:
rc = -EFAULT;
break;
}
/* check if there were problems changing features */
if (rc) {
/* If we don't agree on SP, we sent a confirm for old value.
* However we propagate rc to caller in case option was
* mandatory
*/
if (rc != DCCP_FEAT_SP_NOAGREE)
dccp_feat_empty_confirm(sk, type, feature);
}
/* generate the confirm [if required] */
dccp_feat_flush_confirm(sk);
return rc;
}
EXPORT_SYMBOL_GPL(dccp_feat_change_recv);
int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
u8 *val, u8 len)
{
u8 t;
struct dccp_opt_pend *opt;
struct dccp_sock *dp = dccp_sk(sk);
int rc = 1;
int all_confirmed = 1;
dccp_pr_debug("got feat confirm type=%d feat=%d\n", type, feature);
/* XXX sanity check type & feat */
/* locate our change request */
t = type == DCCPO_CONFIRM_L ? DCCPO_CHANGE_R : DCCPO_CHANGE_L;
list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
dccpop_node) {
if (!opt->dccpop_conf && opt->dccpop_type == t &&
opt->dccpop_feat == feature) {
/* we found it */
/* XXX do sanity check */
opt->dccpop_conf = 1;
/* We got a confirmation---change the option */
dccp_feat_update(sk, opt->dccpop_type,
opt->dccpop_feat, *val);
dccp_pr_debug("feat %d type %d confirmed %d\n",
feature, type, *val);
rc = 0;
break;
}
if (!opt->dccpop_conf)
all_confirmed = 0;
}
/* fix re-transmit timer */
/* XXX gotta make sure that no option negotiation occurs during
* connection shutdown. Consider that the CLOSEREQ is sent and timer is
* on. if all options are confirmed it might kill timer which should
* remain alive until close is received.
*/
if (all_confirmed) {
dccp_pr_debug("clear feat negotiation timer %p\n", sk);
inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS);
}
if (rc)
dccp_pr_debug("feat %d type %d never requested\n",
feature, type);
return 0;
}
EXPORT_SYMBOL_GPL(dccp_feat_confirm_recv);
void dccp_feat_clean(struct sock *sk)
{
struct dccp_sock *dp = dccp_sk(sk);
struct dccp_opt_pend *opt, *next;
list_for_each_entry_safe(opt, next, &dp->dccps_options.dccpo_pending,
dccpop_node) {
BUG_ON(opt->dccpop_val == NULL);
kfree(opt->dccpop_val);
if (opt->dccpop_sc != NULL) {
BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
kfree(opt->dccpop_sc->dccpoc_val);
kfree(opt->dccpop_sc);
}
kfree(opt);
}
INIT_LIST_HEAD(&dp->dccps_options.dccpo_pending);
list_for_each_entry_safe(opt, next, &dp->dccps_options.dccpo_conf,
dccpop_node) {
BUG_ON(opt == NULL);
if (opt->dccpop_val != NULL)
kfree(opt->dccpop_val);
kfree(opt);
}
INIT_LIST_HEAD(&dp->dccps_options.dccpo_conf);
}
EXPORT_SYMBOL_GPL(dccp_feat_clean);
/* this is to be called only when a listening sock creates its child. It is
* assumed by the function---the confirm is not duplicated, but rather it is
* "passed on".
*/
int dccp_feat_clone(struct sock *oldsk, struct sock *newsk)
{
struct dccp_sock *olddp = dccp_sk(oldsk);
struct dccp_sock *newdp = dccp_sk(newsk);
struct dccp_opt_pend *opt;
int rc = 0;
INIT_LIST_HEAD(&newdp->dccps_options.dccpo_pending);
INIT_LIST_HEAD(&newdp->dccps_options.dccpo_conf);
list_for_each_entry(opt, &olddp->dccps_options.dccpo_pending,
dccpop_node) {
struct dccp_opt_pend *newopt;
/* copy the value of the option */
u8 *val = kmalloc(opt->dccpop_len, GFP_ATOMIC);
if (val == NULL)
goto out_clean;
memcpy(val, opt->dccpop_val, opt->dccpop_len);
newopt = kmalloc(sizeof(*newopt), GFP_ATOMIC);
if (newopt == NULL) {
kfree(val);
goto out_clean;
}
/* insert the option */
memcpy(newopt, opt, sizeof(*newopt));
newopt->dccpop_val = val;
list_add_tail(&newopt->dccpop_node,
&newdp->dccps_options.dccpo_pending);
/* XXX what happens with backlogs and multiple connections at
* once...
*/
/* the master socket no longer needs to worry about confirms */
opt->dccpop_sc = 0; /* it's not a memleak---new socket has it */
/* reset state for a new socket */
opt->dccpop_conf = 0;
}
/* XXX not doing anything about the conf queue */
out:
return rc;
out_clean:
dccp_feat_clean(newsk);
rc = -ENOMEM;
goto out;
}
EXPORT_SYMBOL_GPL(dccp_feat_clone);
static int __dccp_feat_init(struct sock *sk, u8 type, u8 feat, u8 *val, u8 len)
{
int rc = -ENOMEM;
u8 *copy = kmalloc(len, GFP_KERNEL);
if (copy != NULL) {
memcpy(copy, val, len);
rc = dccp_feat_change(sk, type, feat, copy, len, GFP_KERNEL);
if (rc)
kfree(copy);
}
return rc;
}
int dccp_feat_init(struct sock *sk)
{
struct dccp_sock *dp = dccp_sk(sk);
int rc;
INIT_LIST_HEAD(&dp->dccps_options.dccpo_pending);
INIT_LIST_HEAD(&dp->dccps_options.dccpo_conf);
/* CCID L */
rc = __dccp_feat_init(sk, DCCPO_CHANGE_L, DCCPF_CCID,
&dp->dccps_options.dccpo_tx_ccid, 1);
if (rc)
goto out;
/* CCID R */
rc = __dccp_feat_init(sk, DCCPO_CHANGE_R, DCCPF_CCID,
&dp->dccps_options.dccpo_rx_ccid, 1);
if (rc)
goto out;
/* Ack ratio */
rc = __dccp_feat_init(sk, DCCPO_CHANGE_L, DCCPF_ACK_RATIO,
&dp->dccps_options.dccpo_ack_ratio, 1);
out:
return rc;
}
EXPORT_SYMBOL_GPL(dccp_feat_init);
#ifndef _DCCP_FEAT_H
#define _DCCP_FEAT_H
/*
* net/dccp/feat.h
*
* An implementation of the DCCP protocol
* Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
*
* 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/types.h>
struct sock;
extern int dccp_feat_change(struct sock *sk, u8 type, u8 feature,
u8 *val, u8 len, gfp_t gfp);
extern int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature,
u8 *val, u8 len);
extern int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
u8 *val, u8 len);
extern void dccp_feat_clean(struct sock *sk);
extern int dccp_feat_clone(struct sock *oldsk, struct sock *newsk);
extern int dccp_feat_init(struct sock *sk);
#endif /* _DCCP_FEAT_H */
......@@ -300,6 +300,9 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk,
goto out_invalid_packet;
}
if (dccp_parse_options(sk, skb))
goto out_invalid_packet;
if (dp->dccps_options.dccpo_send_ack_vector &&
dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
DCCP_SKB_CB(skb)->dccpd_seq,
......
......@@ -28,6 +28,7 @@
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
#include "feat.h"
struct inet_hashinfo __cacheline_aligned dccp_hashinfo = {
.lhash_lock = RW_LOCK_UNLOCKED,
......@@ -535,7 +536,8 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
if (req == NULL)
goto drop;
/* FIXME: process options */
if (dccp_parse_options(sk, skb))
goto drop;
dccp_openreq_init(req, &dp, skb);
......@@ -1049,6 +1051,8 @@ int dccp_v4_init_sock(struct sock *sk)
* setsockopt(CCIDs-I-want/accept). -acme
*/
if (likely(!dccp_ctl_socket_init)) {
int rc;
if (dp->dccps_options.dccpo_send_ack_vector) {
dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(GFP_KERNEL);
if (dp->dccps_hc_rx_ackvec == NULL)
......@@ -1069,8 +1073,16 @@ int dccp_v4_init_sock(struct sock *sk)
dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
return -ENOMEM;
}
} else
rc = dccp_feat_init(sk);
if (rc)
return rc;
} else {
/* control socket doesn't need feat nego */
INIT_LIST_HEAD(&dp->dccps_options.dccpo_pending);
INIT_LIST_HEAD(&dp->dccps_options.dccpo_conf);
dccp_ctl_socket_init = 0;
}
dccp_init_xmit_timers(sk);
icsk->icsk_rto = DCCP_TIMEOUT_INIT;
......@@ -1118,6 +1130,9 @@ int dccp_v4_destroy_sock(struct sock *sk)
ccid_exit(dp->dccps_hc_tx_ccid, sk);
dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
/* clean up feature negotiation state */
dccp_feat_clean(sk);
return 0;
}
......
......@@ -22,6 +22,7 @@
#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,
......@@ -114,6 +115,9 @@ struct sock *dccp_create_openreq_child(struct sock *sk,
newicsk->icsk_rto = DCCP_TIMEOUT_INIT;
do_gettimeofday(&newdp->dccps_epoch);
if (dccp_feat_clone(sk, newsk))
goto out_free;
if (newdp->dccps_options.dccpo_send_ack_vector) {
newdp->dccps_hc_rx_ackvec =
dccp_ackvec_alloc(GFP_ATOMIC);
......
......@@ -21,12 +21,14 @@
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
#include "feat.h"
/* stores the default values for new connection. may be changed with sysctl */
static const struct dccp_options dccpo_default_values = {
.dccpo_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW,
.dccpo_rx_ccid = DCCPF_INITIAL_CCID,
.dccpo_tx_ccid = DCCPF_INITIAL_CCID,
.dccpo_ack_ratio = DCCPF_INITIAL_ACK_RATIO,
.dccpo_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR,
.dccpo_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT,
};
......@@ -69,6 +71,8 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
unsigned char opt, len;
unsigned char *value;
u32 elapsed_time;
int rc;
int mandatory = 0;
memset(opt_recv, 0, sizeof(*opt_recv));
......@@ -100,6 +104,11 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
switch (opt) {
case DCCPO_PADDING:
break;
case DCCPO_MANDATORY:
if (mandatory)
goto out_invalid_option;
mandatory = 1;
break;
case DCCPO_NDP_COUNT:
if (len > 3)
goto out_invalid_option;
......@@ -108,6 +117,31 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
dccp_pr_debug("%sNDP count=%d\n", debug_prefix,
opt_recv->dccpor_ndp);
break;
case DCCPO_CHANGE_L:
/* fall through */
case DCCPO_CHANGE_R:
if (len < 2)
goto out_invalid_option;
rc = dccp_feat_change_recv(sk, opt, *value, value + 1,
len - 1);
/*
* When there is a change error, change_recv is
* responsible for dealing with it. i.e. reply with an
* empty confirm.
* If the change was mandatory, then we need to die.
*/
if (rc && mandatory)
goto out_invalid_option;
break;
case DCCPO_CONFIRM_L:
/* fall through */
case DCCPO_CONFIRM_R:
if (len < 2)
goto out_invalid_option;
if (dccp_feat_confirm_recv(sk, opt, *value,
value + 1, len - 1))
goto out_invalid_option;
break;
case DCCPO_ACK_VECTOR_0:
case DCCPO_ACK_VECTOR_1:
if (pkt_type == DCCP_PKT_DATA)
......@@ -208,6 +242,9 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
sk, opt, len);
break;
}
if (opt != DCCPO_MANDATORY)
mandatory = 0;
}
return 0;
......@@ -356,7 +393,7 @@ void dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
{
struct timeval tv;
u32 now;
dccp_timestamp(sk, &tv);
now = timeval_usecs(&tv) / 10;
/* yes this will overflow but that is the point as we want a
......@@ -402,7 +439,7 @@ static void dccp_insert_option_timestamp_echo(struct sock *sk,
tstamp_echo = htonl(dp->dccps_timestamp_echo);
memcpy(to, &tstamp_echo, 4);
to += 4;
if (elapsed_time_len == 2) {
const u16 var16 = htons((u16)elapsed_time);
memcpy(to, &var16, 2);
......@@ -421,6 +458,93 @@ static void dccp_insert_option_timestamp_echo(struct sock *sk,
dp->dccps_timestamp_time.tv_usec = 0;
}
static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat,
u8 *val, u8 len)
{
u8 *to;
if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 3 > DCCP_MAX_OPT_LEN) {
LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small"
" to insert feature %d option!\n", feat);
return -1;
}
DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3;
to = skb_push(skb, len + 3);
*to++ = type;
*to++ = len + 3;
*to++ = feat;
if (len)
memcpy(to, val, len);
dccp_pr_debug("option %d feat %d len %d\n", type, feat, len);
return 0;
}
static void dccp_insert_feat(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
struct dccp_opt_pend *opt, *next;
int change = 0;
/* confirm any options [NN opts] */
list_for_each_entry_safe(opt, next, &dp->dccps_options.dccpo_conf,
dccpop_node) {
dccp_insert_feat_opt(skb, opt->dccpop_type,
opt->dccpop_feat, opt->dccpop_val,
opt->dccpop_len);
/* fear empty confirms */
if (opt->dccpop_val)
kfree(opt->dccpop_val);
kfree(opt);
}
INIT_LIST_HEAD(&dp->dccps_options.dccpo_conf);
/* see which features we need to send */
list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
dccpop_node) {
/* see if we need to send any confirm */
if (opt->dccpop_sc) {
dccp_insert_feat_opt(skb, opt->dccpop_type + 1,
opt->dccpop_feat,
opt->dccpop_sc->dccpoc_val,
opt->dccpop_sc->dccpoc_len);
BUG_ON(!opt->dccpop_sc->dccpoc_val);
kfree(opt->dccpop_sc->dccpoc_val);
kfree(opt->dccpop_sc);
opt->dccpop_sc = NULL;
}
/* any option not confirmed, re-send it */
if (!opt->dccpop_conf) {
dccp_insert_feat_opt(skb, opt->dccpop_type,
opt->dccpop_feat, opt->dccpop_val,
opt->dccpop_len);
change++;
}
}
/* Retransmit timer.
* If this is the master listening sock, we don't set a timer on it. It
* should be fine because if the dude doesn't receive our RESPONSE
* [which will contain the CHANGE] he will send another REQUEST which
* will "retrnasmit" the change.
*/
if (change && dp->dccps_role != DCCP_ROLE_LISTEN) {
dccp_pr_debug("reset feat negotiation timer %p\n", sk);
/* XXX don't reset the timer on re-transmissions. I.e. reset it
* only when sending new stuff i guess. Currently the timer
* never backs off because on re-transmission it just resets it!
*/
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
inet_csk(sk)->icsk_rto, DCCP_RTO_MAX);
}
}
void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
......@@ -447,6 +571,17 @@ void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
dp->dccps_hc_tx_insert_options = 0;
}
/* Feature negotiation */
switch(DCCP_SKB_CB(skb)->dccpd_type) {
/* Data packets can't do feat negotiation */
case DCCP_PKT_DATA:
case DCCP_PKT_DATAACK:
break;
default:
dccp_insert_feat(sk, skb);
break;
}
/* XXX: insert other options when appropriate */
if (DCCP_SKB_CB(skb)->dccpd_opt_len != 0) {
......
......@@ -64,6 +64,10 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
case DCCP_PKT_DATAACK:
break;
case DCCP_PKT_REQUEST:
set_ack = 0;
/* fall through */
case DCCP_PKT_SYNC:
case DCCP_PKT_SYNCACK:
ackno = dcb->dccpd_seq;
......
......@@ -37,6 +37,7 @@
#include "ccid.h"
#include "dccp.h"
#include "feat.h"
DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly;
......@@ -255,6 +256,39 @@ static int dccp_setsockopt_service(struct sock *sk, const u32 service,
return 0;
}
/* byte 1 is feature. the rest is the preference list */
static int dccp_setsockopt_change(struct sock *sk, int type,
struct dccp_so_feat __user *optval)
{
struct dccp_so_feat opt;
u8 *val;
int rc;
if (copy_from_user(&opt, optval, sizeof(opt)))
return -EFAULT;
val = kmalloc(opt.dccpsf_len, GFP_KERNEL);
if (!val)
return -ENOMEM;
if (copy_from_user(val, opt.dccpsf_val, opt.dccpsf_len)) {
rc = -EFAULT;
goto out_free_val;
}
rc = dccp_feat_change(sk, type, opt.dccpsf_feat, val, opt.dccpsf_len,
GFP_KERNEL);
if (rc)
goto out_free_val;
out:
return rc;
out_free_val:
kfree(val);
goto out;
}
int dccp_setsockopt(struct sock *sk, int level, int optname,
char __user *optval, int optlen)
{
......@@ -284,6 +318,25 @@ int dccp_setsockopt(struct sock *sk, int level, int optname,
case DCCP_SOCKOPT_PACKET_SIZE:
dp->dccps_packet_size = val;
break;
case DCCP_SOCKOPT_CHANGE_L:
if (optlen != sizeof(struct dccp_so_feat))
err = -EINVAL;
else
err = dccp_setsockopt_change(sk, DCCPO_CHANGE_L,
(struct dccp_so_feat *)
optval);
break;
case DCCP_SOCKOPT_CHANGE_R:
if (optlen != sizeof(struct dccp_so_feat))
err = -EINVAL;
else
err = dccp_setsockopt_change(sk, DCCPO_CHANGE_R,
(struct dccp_so_feat *)
optval);
break;
default:
err = -ENOPROTOOPT;
break;
......
......@@ -141,6 +141,17 @@ static void dccp_retransmit_timer(struct sock *sk)
{
struct inet_connection_sock *icsk = inet_csk(sk);
/* retransmit timer is used for feature negotiation throughout
* connection. In this case, no packet is re-transmitted, but rather an
* ack is generated and pending changes are splaced into its options.
*/
if (sk->sk_send_head == NULL) {
dccp_pr_debug("feat negotiation retransmit timeout %p\n", sk);
if (sk->sk_state == DCCP_OPEN)
dccp_send_ack(sk);
goto backoff;
}
/*
* sk->sk_send_head has to have one skb with
* DCCP_SKB_CB(skb)->dccpd_type set to one of the retransmittable DCCP
......@@ -177,6 +188,7 @@ static void dccp_retransmit_timer(struct sock *sk)
goto out;
}
backoff:
icsk->icsk_backoff++;
icsk->icsk_retransmits++;
......
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