[DCCP]: Miscellaneous code tidy-ups
This patch does not change code; it performs some trivial clean/tidy-ups:
* removal of a `debug_prefix' string in favour of the
already existing dccp_role(sk)
* add documentation of structures and constants
* separated out the cases for invalid packets (step 1
of the packet validation)
* removing duplicate statements
* combining declaration & initialisation
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
diff --git a/net/dccp/ackvec.c b/net/dccp/ackvec.c
index f820887..0c54b89 100644
--- a/net/dccp/ackvec.c
+++ b/net/dccp/ackvec.c
@@ -67,10 +67,6 @@
int dccp_insert_option_ackvec(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: " : "server tx: ";
-#endif
struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
int len = av->dccpav_vec_len + 2;
struct timeval now;
@@ -129,9 +125,9 @@
dccp_ackvec_insert_avr(av, avr);
- dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
+ dccp_pr_debug("%s ACK Vector 0, len=%d, ack_seqno=%llu, "
"ack_ackno=%llu\n",
- debug_prefix, avr->dccpavr_sent_len,
+ dccp_role(sk), avr->dccpavr_sent_len,
(unsigned long long)avr->dccpavr_ack_seqno,
(unsigned long long)avr->dccpavr_ack_ackno);
return 0;
@@ -380,14 +376,9 @@
*/
list_for_each_entry_reverse(avr, &av->dccpav_records, dccpavr_node) {
if (ackno == avr->dccpavr_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, "
+ dccp_pr_debug("%s ACK packet 0, len=%d, ack_seqno=%llu, "
"ack_ackno=%llu, ACKED!\n",
- debug_prefix, 1,
+ dccp_role(sk), 1,
(unsigned long long)avr->dccpavr_ack_seqno,
(unsigned long long)avr->dccpavr_ack_ackno);
dccp_ackvec_throw_record(av, avr);
@@ -437,16 +428,10 @@
if (between48(avr->dccpavr_ack_seqno, ackno_end_rl, ackno)) {
const u8 state = *vector & DCCP_ACKVEC_STATE_MASK;
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, "
+ dccp_pr_debug("%s ACK vector 0, len=%d, "
"ack_seqno=%llu, ack_ackno=%llu, "
"ACKED!\n",
- debug_prefix, len,
+ dccp_role(sk), len,
(unsigned long long)
avr->dccpavr_ack_seqno,
(unsigned long long)
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 61c0901..34d6d19 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -518,7 +518,7 @@
sizeof(struct dccp_hdr_reset);
struct sk_buff *skb;
struct dst_entry *dst;
- u64 seqno;
+ u64 seqno = 0;
/* Never send a reset in response to a reset. */
if (rxdh->dccph_type == DCCP_PKT_RESET)
@@ -552,13 +552,11 @@
DCCP_SKB_CB(rxskb)->dccpd_reset_code;
/* See "8.3.1. Abnormal Termination" in RFC 4340 */
- seqno = 0;
if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1);
dccp_hdr_set_seq(dh, seqno);
- dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
- DCCP_SKB_CB(rxskb)->dccpd_seq);
+ dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), DCCP_SKB_CB(rxskb)->dccpd_seq);
dccp_csum_outgoing(skb);
dh->dccph_checksum = dccp_v4_csum_finish(skb, rxskb->nh.iph->saddr,
@@ -734,6 +732,11 @@
EXPORT_SYMBOL_GPL(dccp_v4_do_rcv);
+/**
+ * dccp_invalid_packet - check for malformed packets
+ * Implements RFC 4340, 8.5: Step 1: Check header basics
+ * Packets that fail these checks are ignored and do not receive Resets.
+ */
int dccp_invalid_packet(struct sk_buff *skb)
{
const struct dccp_hdr *dh;
@@ -742,6 +745,7 @@
if (skb->pkt_type != PACKET_HOST)
return 1;
+ /* If the packet is shorter than 12 bytes, drop packet and return */
if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) {
LIMIT_NETDEBUG(KERN_WARNING "DCCP: pskb_may_pull failed\n");
return 1;
@@ -749,42 +753,37 @@
dh = dccp_hdr(skb);
- /* If the packet type is not understood, drop packet and return */
+ /* If P.type is not understood, drop packet and return */
if (dh->dccph_type >= DCCP_PKT_INVALID) {
LIMIT_NETDEBUG(KERN_WARNING "DCCP: invalid packet type\n");
return 1;
}
/*
- * If P.Data Offset is too small for packet type, or too large for
- * packet, drop packet and return
+ * If P.Data Offset is too small for packet type, drop packet and return
*/
if (dh->dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) {
LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) "
- "too small 1\n",
- dh->dccph_doff);
+ "too small\n", dh->dccph_doff);
return 1;
}
-
+ /*
+ * If P.Data Offset is too too large for packet, drop packet and return
+ */
if (!pskb_may_pull(skb, dh->dccph_doff * sizeof(u32))) {
LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) "
- "too small 2\n",
- dh->dccph_doff);
+ "too large\n", dh->dccph_doff);
return 1;
}
- dh = dccp_hdr(skb);
-
/*
* If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet
* has short sequence numbers), drop packet and return
*/
- if (dh->dccph_x == 0 &&
- dh->dccph_type != DCCP_PKT_DATA &&
- dh->dccph_type != DCCP_PKT_ACK &&
- dh->dccph_type != DCCP_PKT_DATAACK) {
- LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.type (%s) not Data, Ack "
- "nor DataAck and P.X == 0\n",
+ if (dh->dccph_type >= DCCP_PKT_DATA &&
+ dh->dccph_type <= DCCP_PKT_DATAACK && dh->dccph_x == 0) {
+ LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.type (%s) not Data||Ack||"
+ "DataAck, while P.X == 0\n",
dccp_packet_name(dh->dccph_type));
return 1;
}
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 2165b17..fc32617 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -318,7 +318,7 @@
sizeof(struct dccp_hdr_reset);
struct sk_buff *skb;
struct flowi fl;
- u64 seqno;
+ u64 seqno = 0;
if (rxdh->dccph_type == DCCP_PKT_RESET)
return;
@@ -345,13 +345,11 @@
DCCP_SKB_CB(rxskb)->dccpd_reset_code;
/* See "8.3.1. Abnormal Termination" in RFC 4340 */
- seqno = 0;
if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1);
dccp_hdr_set_seq(dh, seqno);
- dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
- DCCP_SKB_CB(rxskb)->dccpd_seq);
+ dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), DCCP_SKB_CB(rxskb)->dccpd_seq);
dccp_csum_outgoing(skb);
dh->dccph_checksum = dccp_v6_csum_finish(skb, &rxskb->nh.ipv6h->saddr,
diff --git a/net/dccp/options.c b/net/dccp/options.c
index 2d0ef27..7e50678 100644
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -60,10 +60,6 @@
int dccp_parse_options(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 rx opt: " : "server rx opt: ";
-#endif
const struct dccp_hdr *dh = dccp_hdr(skb);
const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
@@ -119,7 +115,7 @@
goto out_invalid_option;
opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
- dccp_pr_debug("%sNDP count=%d\n", debug_prefix,
+ dccp_pr_debug("%s rx opt: NDP count=%d\n", dccp_role(sk),
opt_recv->dccpor_ndp);
break;
case DCCPO_CHANGE_L:
@@ -165,8 +161,8 @@
dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp;
dccp_timestamp(sk, &dp->dccps_timestamp_time);
- dccp_pr_debug("%sTIMESTAMP=%u, ackno=%llu\n",
- debug_prefix, opt_recv->dccpor_timestamp,
+ dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n",
+ dccp_role(sk), opt_recv->dccpor_timestamp,
(unsigned long long)
DCCP_SKB_CB(skb)->dccpd_ack_seq);
break;
@@ -176,8 +172,8 @@
opt_recv->dccpor_timestamp_echo = ntohl(*(__be32 *)value);
- dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, ackno=%llu, ",
- debug_prefix,
+ dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, "
+ "ackno=%llu, ", dccp_role(sk),
opt_recv->dccpor_timestamp_echo,
len + 2,
(unsigned long long)
@@ -211,8 +207,8 @@
if (elapsed_time > opt_recv->dccpor_elapsed_time)
opt_recv->dccpor_elapsed_time = elapsed_time;
- dccp_pr_debug("%sELAPSED_TIME=%d\n", debug_prefix,
- elapsed_time);
+ dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
+ dccp_role(sk), elapsed_time);
break;
/*
* From RFC 4340, sec. 10.3:
diff --git a/net/dccp/output.c b/net/dccp/output.c
index ef22f3c..c34eada 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -333,6 +333,7 @@
return NULL;
}
+ /* Build and checksum header */
dh = dccp_zeroed_hdr(skb, dccp_header_size);
dh->dccph_sport = inet_sk(sk)->sport;
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 9c9c08c..0225bda 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -452,9 +452,8 @@
static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
char __user *optval, int optlen)
{
- struct dccp_sock *dp;
- int err;
- int val;
+ struct dccp_sock *dp = dccp_sk(sk);
+ int val, err = 0;
if (optlen < sizeof(int))
return -EINVAL;
@@ -466,9 +465,6 @@
return dccp_setsockopt_service(sk, val, optval, optlen);
lock_sock(sk);
- dp = dccp_sk(sk);
- err = 0;
-
switch (optname) {
case DCCP_SOCKOPT_PACKET_SIZE:
dp->dccps_packet_size = val;