forked from Minki/linux
dccp: Registration routines for changing feature values
Two registration routines, for SP and NN features, are provided by this patch, replacing a previous routine which was used for both feature types. These are internal-only routines and therefore start with `__feat_register'. It further exports the known limits of Sequence Window and Ack Ratio as symbolic constants. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Gerrit Renker
David S. Miller
parent
f74e91b6cc
commit
e8ef967a54
@ -25,7 +25,7 @@
|
||||
/*
|
||||
* This implementation should follow RFC 4341
|
||||
*/
|
||||
|
||||
#include "../feat.h"
|
||||
#include "../ccid.h"
|
||||
#include "../dccp.h"
|
||||
#include "ccid2.h"
|
||||
@ -147,8 +147,8 @@ static void ccid2_change_l_ack_ratio(struct sock *sk, u32 val)
|
||||
DCCP_WARN("Limiting Ack Ratio (%u) to %u\n", val, max_ratio);
|
||||
val = max_ratio;
|
||||
}
|
||||
if (val > 0xFFFF) /* RFC 4340, 11.3 */
|
||||
val = 0xFFFF;
|
||||
if (val > DCCPF_ACK_RATIO_MAX)
|
||||
val = DCCPF_ACK_RATIO_MAX;
|
||||
|
||||
if (val == dp->dccps_l_ack_ratio)
|
||||
return;
|
||||
|
||||
192
net/dccp/feat.c
192
net/dccp/feat.c
@ -92,6 +92,18 @@ static u8 dccp_feat_type(u8 feat_num)
|
||||
return dccp_feat_table[idx].reconciliation;
|
||||
}
|
||||
|
||||
static int dccp_feat_default_value(u8 feat_num)
|
||||
{
|
||||
int idx = dccp_feat_index(feat_num);
|
||||
/*
|
||||
* There are no default values for unknown features, so encountering a
|
||||
* negative index here indicates a serious problem somewhere else.
|
||||
*/
|
||||
DCCP_BUG_ON(idx < 0);
|
||||
|
||||
return idx < 0 ? 0 : dccp_feat_table[idx].default_value;
|
||||
}
|
||||
|
||||
/* copy constructor, fval must not already contain allocated memory */
|
||||
static int dccp_feat_clone_sp_val(dccp_feat_val *fval, u8 const *val, u8 len)
|
||||
{
|
||||
@ -155,6 +167,63 @@ static void dccp_feat_entry_destructor(struct dccp_feat_entry *entry)
|
||||
* - list is sorted in increasing order of feature number (faster lookup)
|
||||
*/
|
||||
|
||||
/**
|
||||
* dccp_feat_entry_new - Central list update routine (called by all others)
|
||||
* @head: list to add to
|
||||
* @feat: feature number
|
||||
* @local: whether the local (1) or remote feature with number @feat is meant
|
||||
* This is the only constructor and serves to ensure the above invariants.
|
||||
*/
|
||||
static struct dccp_feat_entry *
|
||||
dccp_feat_entry_new(struct list_head *head, u8 feat, bool local)
|
||||
{
|
||||
struct dccp_feat_entry *entry;
|
||||
|
||||
list_for_each_entry(entry, head, node)
|
||||
if (entry->feat_num == feat && entry->is_local == local) {
|
||||
dccp_feat_val_destructor(entry->feat_num, &entry->val);
|
||||
return entry;
|
||||
} else if (entry->feat_num > feat) {
|
||||
head = &entry->node;
|
||||
break;
|
||||
}
|
||||
|
||||
entry = kmalloc(sizeof(*entry), gfp_any());
|
||||
if (entry != NULL) {
|
||||
entry->feat_num = feat;
|
||||
entry->is_local = local;
|
||||
list_add_tail(&entry->node, head);
|
||||
}
|
||||
return entry;
|
||||
}
|
||||
|
||||
/**
|
||||
* dccp_feat_push_change - Add/overwrite a Change option in the list
|
||||
* @fn_list: feature-negotiation list to update
|
||||
* @feat: one of %dccp_feature_numbers
|
||||
* @local: whether local (1) or remote (0) @feat_num is meant
|
||||
* @needs_mandatory: whether to use Mandatory feature negotiation options
|
||||
* @fval: pointer to NN/SP value to be inserted (will be copied)
|
||||
*/
|
||||
static int dccp_feat_push_change(struct list_head *fn_list, u8 feat, u8 local,
|
||||
u8 mandatory, dccp_feat_val *fval)
|
||||
{
|
||||
struct dccp_feat_entry *new = dccp_feat_entry_new(fn_list, feat, local);
|
||||
|
||||
if (new == NULL)
|
||||
return -ENOMEM;
|
||||
|
||||
new->feat_num = feat;
|
||||
new->is_local = local;
|
||||
new->state = FEAT_INITIALISING;
|
||||
new->needs_confirm = 0;
|
||||
new->empty_confirm = 0;
|
||||
new->val = *fval;
|
||||
new->needs_mandatory = mandatory;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static inline void dccp_feat_list_pop(struct dccp_feat_entry *entry)
|
||||
{
|
||||
list_del(&entry->node);
|
||||
@ -190,6 +259,95 @@ cloning_failed:
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
static u8 dccp_feat_is_valid_nn_val(u8 feat_num, u64 val)
|
||||
{
|
||||
switch (feat_num) {
|
||||
case DCCPF_ACK_RATIO:
|
||||
return val <= DCCPF_ACK_RATIO_MAX;
|
||||
case DCCPF_SEQUENCE_WINDOW:
|
||||
return val >= DCCPF_SEQ_WMIN && val <= DCCPF_SEQ_WMAX;
|
||||
}
|
||||
return 0; /* feature unknown - so we can't tell */
|
||||
}
|
||||
|
||||
/* check that SP values are within the ranges defined in RFC 4340 */
|
||||
static u8 dccp_feat_is_valid_sp_val(u8 feat_num, u8 val)
|
||||
{
|
||||
switch (feat_num) {
|
||||
case DCCPF_CCID:
|
||||
return val == DCCPC_CCID2 || val == DCCPC_CCID3;
|
||||
/* Type-check Boolean feature values: */
|
||||
case DCCPF_SHORT_SEQNOS:
|
||||
case DCCPF_ECN_INCAPABLE:
|
||||
case DCCPF_SEND_ACK_VECTOR:
|
||||
case DCCPF_SEND_NDP_COUNT:
|
||||
case DCCPF_DATA_CHECKSUM:
|
||||
case DCCPF_SEND_LEV_RATE:
|
||||
return val < 2;
|
||||
case DCCPF_MIN_CSUM_COVER:
|
||||
return val < 16;
|
||||
}
|
||||
return 0; /* feature unknown */
|
||||
}
|
||||
|
||||
static u8 dccp_feat_sp_list_ok(u8 feat_num, u8 const *sp_list, u8 sp_len)
|
||||
{
|
||||
if (sp_list == NULL || sp_len < 1)
|
||||
return 0;
|
||||
while (sp_len--)
|
||||
if (!dccp_feat_is_valid_sp_val(feat_num, *sp_list++))
|
||||
return 0;
|
||||
return 1;
|
||||
}
|
||||
|
||||
/**
|
||||
* __feat_register_nn - Register new NN value on socket
|
||||
* @fn: feature-negotiation list to register with
|
||||
* @feat: an NN feature from %dccp_feature_numbers
|
||||
* @mandatory: use Mandatory option if 1
|
||||
* @nn_val: value to register (restricted to 4 bytes)
|
||||
* Note that NN features are local by definition (RFC 4340, 6.3.2).
|
||||
*/
|
||||
static int __feat_register_nn(struct list_head *fn, u8 feat,
|
||||
u8 mandatory, u64 nn_val)
|
||||
{
|
||||
dccp_feat_val fval = { .nn = nn_val };
|
||||
|
||||
if (dccp_feat_type(feat) != FEAT_NN ||
|
||||
!dccp_feat_is_valid_nn_val(feat, nn_val))
|
||||
return -EINVAL;
|
||||
|
||||
/* Don't bother with default values, they will be activated anyway. */
|
||||
if (nn_val - (u64)dccp_feat_default_value(feat) == 0)
|
||||
return 0;
|
||||
|
||||
return dccp_feat_push_change(fn, feat, 1, mandatory, &fval);
|
||||
}
|
||||
|
||||
/**
|
||||
* __feat_register_sp - Register new SP value/list on socket
|
||||
* @fn: feature-negotiation list to register with
|
||||
* @feat: an SP feature from %dccp_feature_numbers
|
||||
* @is_local: whether the local (1) or the remote (0) @feat is meant
|
||||
* @mandatory: use Mandatory option if 1
|
||||
* @sp_val: SP value followed by optional preference list
|
||||
* @sp_len: length of @sp_val in bytes
|
||||
*/
|
||||
static int __feat_register_sp(struct list_head *fn, u8 feat, u8 is_local,
|
||||
u8 mandatory, u8 const *sp_val, u8 sp_len)
|
||||
{
|
||||
dccp_feat_val fval;
|
||||
|
||||
if (dccp_feat_type(feat) != FEAT_SP ||
|
||||
!dccp_feat_sp_list_ok(feat, sp_val, sp_len))
|
||||
return -EINVAL;
|
||||
|
||||
if (dccp_feat_clone_sp_val(&fval, sp_val, sp_len))
|
||||
return -ENOMEM;
|
||||
|
||||
return dccp_feat_push_change(fn, feat, is_local, mandatory, &fval);
|
||||
}
|
||||
|
||||
int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature,
|
||||
u8 *val, u8 len, gfp_t gfp)
|
||||
{
|
||||
@ -726,42 +884,30 @@ out_clean:
|
||||
|
||||
EXPORT_SYMBOL_GPL(dccp_feat_clone);
|
||||
|
||||
static int __dccp_feat_init(struct dccp_minisock *dmsk, u8 type, u8 feat,
|
||||
u8 *val, u8 len)
|
||||
{
|
||||
int rc = -ENOMEM;
|
||||
u8 *copy = kmemdup(val, len, GFP_KERNEL);
|
||||
|
||||
if (copy != NULL) {
|
||||
rc = dccp_feat_change(dmsk, type, feat, copy, len, GFP_KERNEL);
|
||||
if (rc)
|
||||
kfree(copy);
|
||||
}
|
||||
return rc;
|
||||
}
|
||||
|
||||
int dccp_feat_init(struct dccp_minisock *dmsk)
|
||||
int dccp_feat_init(struct sock *sk)
|
||||
{
|
||||
struct dccp_sock *dp = dccp_sk(sk);
|
||||
struct dccp_minisock *dmsk = dccp_msk(sk);
|
||||
int rc;
|
||||
|
||||
INIT_LIST_HEAD(&dmsk->dccpms_pending);
|
||||
INIT_LIST_HEAD(&dmsk->dccpms_conf);
|
||||
INIT_LIST_HEAD(&dmsk->dccpms_pending); /* XXX no longer used */
|
||||
INIT_LIST_HEAD(&dmsk->dccpms_conf); /* XXX no longer used */
|
||||
|
||||
/* CCID L */
|
||||
rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_CCID,
|
||||
&dmsk->dccpms_tx_ccid, 1);
|
||||
rc = __feat_register_sp(&dp->dccps_featneg, DCCPF_CCID, 1, 0,
|
||||
&dmsk->dccpms_tx_ccid, 1);
|
||||
if (rc)
|
||||
goto out;
|
||||
|
||||
/* CCID R */
|
||||
rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_R, DCCPF_CCID,
|
||||
&dmsk->dccpms_rx_ccid, 1);
|
||||
rc = __feat_register_sp(&dp->dccps_featneg, DCCPF_CCID, 0, 0,
|
||||
&dmsk->dccpms_rx_ccid, 1);
|
||||
if (rc)
|
||||
goto out;
|
||||
|
||||
/* Ack ratio */
|
||||
rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_ACK_RATIO,
|
||||
&dmsk->dccpms_ack_ratio, 1);
|
||||
rc = __feat_register_nn(&dp->dccps_featneg, DCCPF_ACK_RATIO, 0,
|
||||
dmsk->dccpms_ack_ratio);
|
||||
out:
|
||||
return rc;
|
||||
}
|
||||
|
||||
@ -14,6 +14,15 @@
|
||||
#include <linux/types.h>
|
||||
#include "dccp.h"
|
||||
|
||||
/*
|
||||
* Known limit values
|
||||
*/
|
||||
/* Ack Ratio takes 2-byte integer values (11.3) */
|
||||
#define DCCPF_ACK_RATIO_MAX 0xFFFF
|
||||
/* Wmin=32 and Wmax=2^46-1 from 7.5.2 */
|
||||
#define DCCPF_SEQ_WMIN 32
|
||||
#define DCCPF_SEQ_WMAX 0x3FFFFFFFFFFFull
|
||||
|
||||
enum dccp_feat_type {
|
||||
FEAT_AT_RX = 1, /* located at RX side of half-connection */
|
||||
FEAT_AT_TX = 2, /* located at TX side of half-connection */
|
||||
@ -75,6 +84,20 @@ static inline u8 dccp_feat_genopt(struct dccp_feat_entry *entry)
|
||||
return entry->is_local ? DCCPO_CHANGE_L : DCCPO_CHANGE_R;
|
||||
}
|
||||
|
||||
/**
|
||||
* struct ccid_dependency - Track changes resulting from choosing a CCID
|
||||
* @dependent_feat: one of %dccp_feature_numbers
|
||||
* @is_local: local (1) or remote (0) @dependent_feat
|
||||
* @is_mandatory: whether presence of @dependent_feat is mission-critical or not
|
||||
* @val: corresponding default value for @dependent_feat (u8 is sufficient here)
|
||||
*/
|
||||
struct ccid_dependency {
|
||||
u8 dependent_feat;
|
||||
bool is_local:1,
|
||||
is_mandatory:1;
|
||||
u8 val;
|
||||
};
|
||||
|
||||
#ifdef CONFIG_IP_DCCP_DEBUG
|
||||
extern const char *dccp_feat_typename(const u8 type);
|
||||
extern const char *dccp_feat_name(const u8 feat);
|
||||
@ -97,6 +120,6 @@ extern int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
|
||||
extern void dccp_feat_clean(struct dccp_minisock *dmsk);
|
||||
extern int dccp_feat_clone(struct sock *oldsk, struct sock *newsk);
|
||||
extern int dccp_feat_clone_list(struct list_head const *, struct list_head *);
|
||||
extern int dccp_feat_init(struct dccp_minisock *dmsk);
|
||||
extern int dccp_feat_init(struct sock *sk);
|
||||
|
||||
#endif /* _DCCP_FEAT_H */
|
||||
|
||||
@ -202,7 +202,7 @@ int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized)
|
||||
* setsockopt(CCIDs-I-want/accept). -acme
|
||||
*/
|
||||
if (likely(ctl_sock_initialized)) {
|
||||
int rc = dccp_feat_init(dmsk);
|
||||
int rc = dccp_feat_init(sk);
|
||||
|
||||
if (rc)
|
||||
return rc;
|
||||
|
||||
Loading…
Reference in New Issue
Block a user