dccp ccid-2: Separate internals of Ack Vectors from option-parsing code
This patch * separates Ack Vector housekeeping code from option-insertion code; * shifts option-specific code from ackvec.c into options.c; * introduces a dedicated routine to take care of the Ack Vector records; * simplifies the dccp_ackvec_insert_avr() routine: the BUG_ON was redundant, since the list is automatically arranged in descending order of ack_seqno. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
This commit is contained in:
Gerrit Renker
Родитель
ff49e27089
Коммит
4829007c7b
|
|
@ -52,99 +52,35 @@ void dccp_ackvec_free(struct dccp_ackvec *av)
|
|||
}
|
||||
}
|
||||
|
||||
static void dccp_ackvec_insert_avr(struct dccp_ackvec *av,
|
||||
struct dccp_ackvec_record *avr)
|
||||
/**
|
||||
* dccp_ackvec_update_records - Record information about sent Ack Vectors
|
||||
* @av: Ack Vector records to update
|
||||
* @seqno: Sequence number of the packet carrying the Ack Vector just sent
|
||||
* @nonce_sum: The sum of all buffer nonces contained in the Ack Vector
|
||||
*/
|
||||
int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seqno, u8 nonce_sum)
|
||||
{
|
||||
/*
|
||||
* AVRs are sorted by seqno. Since we are sending them in order, we
|
||||
* just add the AVR at the head of the list.
|
||||
* -sorbo.
|
||||
*/
|
||||
if (!list_empty(&av->av_records)) {
|
||||
const struct dccp_ackvec_record *head =
|
||||
list_entry(av->av_records.next,
|
||||
struct dccp_ackvec_record,
|
||||
avr_node);
|
||||
BUG_ON(before48(avr->avr_ack_seqno, head->avr_ack_seqno));
|
||||
}
|
||||
|
||||
list_add(&avr->avr_node, &av->av_records);
|
||||
}
|
||||
|
||||
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;
|
||||
/* Figure out how many options do we need to represent the ackvec */
|
||||
const u8 nr_opts = DIV_ROUND_UP(av->av_vec_len, DCCP_SINGLE_OPT_MAXLEN);
|
||||
u16 len = av->av_vec_len + 2 * nr_opts;
|
||||
u8 i, nonce = 0;
|
||||
const unsigned char *tail, *from;
|
||||
unsigned char *to;
|
||||
struct dccp_ackvec_record *avr;
|
||||
|
||||
if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
|
||||
return -1;
|
||||
|
||||
avr = kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
|
||||
if (avr == NULL)
|
||||
return -1;
|
||||
return -ENOBUFS;
|
||||
|
||||
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
|
||||
|
||||
to = skb_push(skb, len);
|
||||
len = av->av_vec_len;
|
||||
from = av->av_buf + av->av_buf_head;
|
||||
tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
|
||||
|
||||
for (i = 0; i < nr_opts; ++i) {
|
||||
int copylen = len;
|
||||
|
||||
if (len > DCCP_SINGLE_OPT_MAXLEN)
|
||||
copylen = DCCP_SINGLE_OPT_MAXLEN;
|
||||
|
||||
/*
|
||||
* RFC 4340, 12.2: Encode the Nonce Echo for this Ack Vector via
|
||||
* its type; ack_nonce is the sum of all individual buf_nonce's.
|
||||
*/
|
||||
nonce ^= av->av_buf_nonce[i];
|
||||
|
||||
*to++ = DCCPO_ACK_VECTOR_0 + av->av_buf_nonce[i];
|
||||
*to++ = copylen + 2;
|
||||
|
||||
/* Check if buf_head wraps */
|
||||
if (from + copylen > tail) {
|
||||
const u16 tailsize = tail - from;
|
||||
|
||||
memcpy(to, from, tailsize);
|
||||
to += tailsize;
|
||||
len -= tailsize;
|
||||
copylen -= tailsize;
|
||||
from = av->av_buf;
|
||||
}
|
||||
|
||||
memcpy(to, from, copylen);
|
||||
from += copylen;
|
||||
to += copylen;
|
||||
len -= copylen;
|
||||
}
|
||||
|
||||
/*
|
||||
* Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
|
||||
*/
|
||||
avr->avr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
|
||||
avr->avr_ack_seqno = seqno;
|
||||
avr->avr_ack_ptr = av->av_buf_head;
|
||||
avr->avr_ack_ackno = av->av_buf_ackno;
|
||||
avr->avr_ack_nonce = nonce;
|
||||
avr->avr_ack_nonce = nonce_sum;
|
||||
avr->avr_ack_runlen = dccp_ackvec_runlen(av->av_buf + av->av_buf_head);
|
||||
/*
|
||||
* Since GSS is incremented for each packet, the list is automatically
|
||||
* arranged in descending order of @ack_seqno.
|
||||
*/
|
||||
list_add(&avr->avr_node, &av->av_records);
|
||||
|
||||
dccp_ackvec_insert_avr(av, avr);
|
||||
|
||||
dccp_pr_debug("%s ACK Vector 0, len=%d, ack_seqno=%llu, "
|
||||
"ack_ackno=%llu\n",
|
||||
dccp_role(sk), avr->avr_ack_runlen,
|
||||
dccp_pr_debug("Added Vector, ack_seqno=%llu, ack_ackno=%llu (rl=%u)\n",
|
||||
(unsigned long long)avr->avr_ack_seqno,
|
||||
(unsigned long long)avr->avr_ack_ackno);
|
||||
(unsigned long long)avr->avr_ack_ackno,
|
||||
avr->avr_ack_runlen);
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -112,7 +112,7 @@ extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
|
|||
u64 *ackno, const u8 opt,
|
||||
const u8 *value, const u8 len);
|
||||
|
||||
extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);
|
||||
extern int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seq, u8 sum);
|
||||
|
||||
static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
|
||||
{
|
||||
|
|
@ -155,8 +155,7 @@ static inline int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
|
|||
return -1;
|
||||
}
|
||||
|
||||
static inline int dccp_insert_option_ackvec(const struct sock *sk,
|
||||
const struct sk_buff *skb)
|
||||
static inline int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seq, u8 nonce)
|
||||
{
|
||||
return -1;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -428,6 +428,66 @@ static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
|
||||
{
|
||||
struct dccp_sock *dp = dccp_sk(sk);
|
||||
struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
|
||||
/* Figure out how many options do we need to represent the ackvec */
|
||||
const u8 nr_opts = DIV_ROUND_UP(av->av_vec_len, DCCP_SINGLE_OPT_MAXLEN);
|
||||
u16 len = av->av_vec_len + 2 * nr_opts;
|
||||
u8 i, nonce = 0;
|
||||
const unsigned char *tail, *from;
|
||||
unsigned char *to;
|
||||
|
||||
if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
|
||||
return -1;
|
||||
|
||||
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
|
||||
|
||||
to = skb_push(skb, len);
|
||||
len = av->av_vec_len;
|
||||
from = av->av_buf + av->av_buf_head;
|
||||
tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
|
||||
|
||||
for (i = 0; i < nr_opts; ++i) {
|
||||
int copylen = len;
|
||||
|
||||
if (len > DCCP_SINGLE_OPT_MAXLEN)
|
||||
copylen = DCCP_SINGLE_OPT_MAXLEN;
|
||||
|
||||
/*
|
||||
* RFC 4340, 12.2: Encode the Nonce Echo for this Ack Vector via
|
||||
* its type; ack_nonce is the sum of all individual buf_nonce's.
|
||||
*/
|
||||
nonce ^= av->av_buf_nonce[i];
|
||||
|
||||
*to++ = DCCPO_ACK_VECTOR_0 + av->av_buf_nonce[i];
|
||||
*to++ = copylen + 2;
|
||||
|
||||
/* Check if buf_head wraps */
|
||||
if (from + copylen > tail) {
|
||||
const u16 tailsize = tail - from;
|
||||
|
||||
memcpy(to, from, tailsize);
|
||||
to += tailsize;
|
||||
len -= tailsize;
|
||||
copylen -= tailsize;
|
||||
from = av->av_buf;
|
||||
}
|
||||
|
||||
memcpy(to, from, copylen);
|
||||
from += copylen;
|
||||
to += copylen;
|
||||
len -= copylen;
|
||||
}
|
||||
/*
|
||||
* Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
|
||||
*/
|
||||
if (dccp_ackvec_update_records(av, DCCP_SKB_CB(skb)->dccpd_seq, nonce))
|
||||
return -ENOBUFS;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* dccp_insert_option_mandatory - Mandatory option (5.8.2)
|
||||
* Note that since we are using skb_push, this function needs to be called
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче