Commit 09dbc389 authored by Gerrit Renker's avatar Gerrit Renker Committed by David S. Miller
Browse files

[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: default avatarGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@mandriva.com>
parent c02fdc0e

include/linux/dccp.h

+17 −1
Original line number Diff line number Diff line
@@ -209,6 +209,7 @@ struct dccp_so_feat { 
#define DCCP_SOCKOPT_CCID_RX_INFO	128

#define DCCP_SOCKOPT_CCID_TX_INFO	192



/* maximum number of services provided on the same listening port */

#define DCCP_SERVICE_LIST_MAX_LEN      32



#ifdef __KERNEL__
@@ -355,6 +356,9 @@ static inline unsigned int dccp_hdr_len(const struct sk_buff *skb) 
  * @dccpms_ccid - Congestion Control Id (CCID) (section 10)

  * @dccpms_send_ack_vector - Send Ack Vector Feature (section 11.5)

  * @dccpms_send_ndp_count - Send NDP Count Feature (7.7.2)

  * @dccpms_ack_ratio - Ack Ratio Feature (section 11.3)

  * @dccpms_pending - List of features being negotiated

  * @dccpms_conf -

  */

struct dccp_minisock {

	__u64			dccpms_sequence_window;
@@ -452,14 +456,26 @@ struct dccp_ackvec; 
 * @dccps_gss - greatest sequence number sent

 * @dccps_gsr - greatest valid sequence number received

 * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss

 * @dccps_service - first (passive sock) or unique (active sock) service code

 * @dccps_service_list - second .. last service code on passive socket

 * @dccps_timestamp_time - time of latest TIMESTAMP option

 * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option

 * @dccps_packet_size - Set thru setsockopt

 * @dccps_role - Role of this sock, one of %dccp_role

 * @dccps_l_ack_ratio -

 * @dccps_r_ack_ratio -

 * @dccps_pcslen - sender   partial checksum coverage (via sockopt)

 * @dccps_pcrlen - receiver partial checksum coverage (via sockopt)

 * @dccps_ndp_count - number of Non Data Packets since last data packet

 * @dccps_mss_cache -

 * @dccps_minisock -

 * @dccps_hc_rx_ackvec - rx half connection ack vector

 * @dccps_hc_rx_ccid -

 * @dccps_hc_tx_ccid -

 * @dccps_options_received -

 * @dccps_epoch -

 * @dccps_role - Role of this sock, one of %dccp_role

 * @dccps_hc_rx_insert_options -

 * @dccps_hc_tx_insert_options -

 * @dccps_xmit_timer - timer for when CCID is not ready to send

 */

struct dccp_sock {

net/dccp/ackvec.c

+6 −21
Original line number Diff line number Diff line
@@ -67,10 +67,6 @@ static void dccp_ackvec_insert_avr(struct dccp_ackvec *av, 
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;
@@ -131,7 +127,7 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb) 


	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 @@ void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk, 
	 */

	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("%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 @@ found: 
		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("%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)

net/dccp/ipv4.c

+19 −20
Original line number Diff line number Diff line
@@ -518,7 +518,7 @@ static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb) 
				       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 @@ static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb) 
				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 @@ discard: 


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 @@ int dccp_invalid_packet(struct sk_buff *skb) 
	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 @@ int dccp_invalid_packet(struct sk_buff *skb) 


	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;

	}

net/dccp/ipv6.c

+2 −4
Original line number Diff line number Diff line
@@ -318,7 +318,7 @@ static void dccp_v6_ctl_send_reset(struct sk_buff *rxskb) 
				       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 @@ static void dccp_v6_ctl_send_reset(struct sk_buff *rxskb) 
				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,

net/dccp/options.c

+7 −11
Original line number Diff line number Diff line
@@ -60,10 +60,6 @@ static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len) 
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 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) 
				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 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) 
			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 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) 


			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 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) 
			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:

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