dccp: Add packet type information to CCID-specific option parsing

This patch ...
 1. adds packet type information to ccid_hc_{rx,tx}_parse_options(). This is 
    necessary, since table 3 in RFC 4340, 5.8 leaves it to the CCIDs to state
    which options may (not) appear on what packet type.
 
 2. adds such a check for CCID-3's {Loss Event, Receive} Rate as specified in
    RFC 4340 8.3 ("Receive Rate options MUST NOT be sent on DCCP-Data packets")
    and 8.5 ("Loss Event Rate options MUST NOT be sent on DCCP-Data packets").

 3. removes an unused argument `idx' from ccid_hc_{rx,tx}_parse_options(). This
    is also no longer necessary, since the CCID-specific option-parsing routines
    are passed every single parameter of the type-length-value option encoding.

Also added documentation and made argument naming scheme consistent.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
This commit is contained in:
Gerrit Renker 2008-09-04 07:30:19 +02:00
parent 47a61e7b43
commit 3306c781ff
3 changed files with 35 additions and 41 deletions

View File

@ -60,18 +60,14 @@ struct ccid_operations {
void (*ccid_hc_tx_exit)(struct sock *sk);
void (*ccid_hc_rx_packet_recv)(struct sock *sk,
struct sk_buff *skb);
int (*ccid_hc_rx_parse_options)(struct sock *sk,
unsigned char option,
unsigned char len, u16 idx,
unsigned char* value);
int (*ccid_hc_rx_parse_options)(struct sock *sk, u8 pkt,
u8 opt, u8 *val, u8 len);
int (*ccid_hc_rx_insert_options)(struct sock *sk,
struct sk_buff *skb);
void (*ccid_hc_tx_packet_recv)(struct sock *sk,
struct sk_buff *skb);
int (*ccid_hc_tx_parse_options)(struct sock *sk,
unsigned char option,
unsigned char len, u16 idx,
unsigned char* value);
int (*ccid_hc_tx_parse_options)(struct sock *sk, u8 pkt,
u8 opt, u8 *val, u8 len);
int (*ccid_hc_tx_send_packet)(struct sock *sk,
struct sk_buff *skb);
void (*ccid_hc_tx_packet_sent)(struct sock *sk,
@ -163,27 +159,31 @@ static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk,
ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb);
}
/**
* ccid_hc_tx_parse_options - Parse CCID-specific options sent by the receiver
* @pkt: type of packet that @opt appears on (RFC 4340, 5.1)
* @opt: the CCID-specific option type (RFC 4340, 5.8 and 10.3)
* @val: value of @opt
* @len: length of @val in bytes
*/
static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk,
unsigned char option,
unsigned char len, u16 idx,
unsigned char* value)
u8 pkt, u8 opt, u8 *val, u8 len)
{
int rc = 0;
if (ccid->ccid_ops->ccid_hc_tx_parse_options != NULL)
rc = ccid->ccid_ops->ccid_hc_tx_parse_options(sk, option, len, idx,
value);
return rc;
if (ccid->ccid_ops->ccid_hc_tx_parse_options == NULL)
return 0;
return ccid->ccid_ops->ccid_hc_tx_parse_options(sk, pkt, opt, val, len);
}
/**
* ccid_hc_rx_parse_options - Parse CCID-specific options sent by the sender
* Arguments are analogous to ccid_hc_tx_parse_options()
*/
static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk,
unsigned char option,
unsigned char len, u16 idx,
unsigned char* value)
u8 pkt, u8 opt, u8 *val, u8 len)
{
int rc = 0;
if (ccid->ccid_ops->ccid_hc_rx_parse_options != NULL)
rc = ccid->ccid_ops->ccid_hc_rx_parse_options(sk, option, len, idx, value);
return rc;
if (ccid->ccid_ops->ccid_hc_rx_parse_options == NULL)
return 0;
return ccid->ccid_ops->ccid_hc_rx_parse_options(sk, pkt, opt, val, len);
}
static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk,

View File

@ -483,9 +483,8 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
jiffies + usecs_to_jiffies(t_nfb));
}
static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option,
unsigned char len, u16 idx,
unsigned char *value)
static int ccid3_hc_tx_parse_options(struct sock *sk, u8 packet_type,
u8 option, u8 *optval, u8 optlen)
{
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
struct ccid3_options_received *opt_recv = &hctx->options_received;
@ -494,12 +493,15 @@ static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option,
switch (option) {
case TFRC_OPT_RECEIVE_RATE:
case TFRC_OPT_LOSS_EVENT_RATE:
if (unlikely(len != 4)) {
/* Must be ignored on Data packets, cf. RFC 4342 8.3 and 8.5 */
if (packet_type == DCCP_PKT_DATA)
break;
if (unlikely(optlen != 4)) {
DCCP_WARN("%s(%p), invalid len %d for %u\n",
dccp_role(sk), sk, len, option);
dccp_role(sk), sk, optlen, option);
return -EINVAL;
}
opt_val = ntohl(get_unaligned((__be32 *)value));
opt_val = ntohl(get_unaligned((__be32 *)optval));
if (option == TFRC_OPT_RECEIVE_RATE) {
opt_recv->ccid3or_receive_rate = opt_val;

View File

@ -226,23 +226,15 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
dccp_role(sk), elapsed_time);
break;
case 128 ... 191: {
const u16 idx = value - options;
case 128 ... 191:
if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk,
opt, len, idx,
value) != 0)
pkt_type, opt, value, len))
goto out_invalid_option;
}
break;
case 192 ... 255: {
const u16 idx = value - options;
case 192 ... 255:
if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
opt, len, idx,
value) != 0)
pkt_type, opt, value, len))
goto out_invalid_option;
}
break;
default:
DCCP_CRIT("DCCP(%p): option %d(len=%d) not "