Commit d8ef2c29 authored by Gerrit Renker's avatar Gerrit Renker Committed by Arnaldo Carvalho de Melo
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[DCCP]: Convert Reset code into socket error number 



This adds support for converting the 11 currently defined Reset codes into system
error numbers, which are stored in sk_err for further interpretation.

This makes the externally visible API behaviour similar to TCP, since a client
connecting to a non-existing port will experience ECONNREFUSED.

* Code 0, Unspecified, is interpreted as non-error (0);
* Code 1, Closed (normal termination), also maps into 0;
* Code 2, Aborted, maps into "Connection reset by peer" (ECONNRESET);
* Code 3, No Connection and
  Code 7, Connection Refused, map into "Connection refused" (ECONNREFUSED);
* Code 4, Packet Error, maps into "No message of desired type" (ENOMSG);
* Code 5, Option Error, maps into "Illegal byte sequence" (EILSEQ);
* Code 6, Mandatory Error, maps into "Operation not supported on transport endpoint" (EOPNOTSUPP);
* Code 8, Bad Service Code, maps into "Invalid request code" (EBADRQC);
* Code 9, Too Busy, maps into "Too many users" (EUSERS);
* Code 10, Bad Init Cookie, maps into "Invalid request descriptor" (EBADR);
* Code 11, Aggression Penalty, maps into "Quota exceeded" (EDQUOT)
  which makes sense in terms of using more than the `fair share' of bandwidth.

Signed-off-by: default avatarGerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: default avatarIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 1238d087

include/linux/dccp.h

+2 −0
Original line number Diff line number Diff line
@@ -144,6 +144,8 @@ enum dccp_reset_codes { 
	DCCP_RESET_CODE_TOO_BUSY,

	DCCP_RESET_CODE_BAD_INIT_COOKIE,

	DCCP_RESET_CODE_AGGRESSION_PENALTY,



	DCCP_MAX_RESET_CODES		/* Leave at the end!  */

};



/* DCCP options */

net/dccp/input.c

+39 −9
Original line number Diff line number Diff line
@@ -58,6 +58,42 @@ static void dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb) 
	dccp_send_close(sk, 0);

}



static u8 dccp_reset_code_convert(const u8 code)

{

	const u8 error_code[] = {

	[DCCP_RESET_CODE_CLOSED]	     = 0,	/* normal termination */

	[DCCP_RESET_CODE_UNSPECIFIED]	     = 0,	/* nothing known */

	[DCCP_RESET_CODE_ABORTED]	     = ECONNRESET,



	[DCCP_RESET_CODE_NO_CONNECTION]	     = ECONNREFUSED,

	[DCCP_RESET_CODE_CONNECTION_REFUSED] = ECONNREFUSED,

	[DCCP_RESET_CODE_TOO_BUSY]	     = EUSERS,

	[DCCP_RESET_CODE_AGGRESSION_PENALTY] = EDQUOT,



	[DCCP_RESET_CODE_PACKET_ERROR]	     = ENOMSG,

	[DCCP_RESET_CODE_BAD_INIT_COOKIE]    = EBADR,

	[DCCP_RESET_CODE_BAD_SERVICE_CODE]   = EBADRQC,

	[DCCP_RESET_CODE_OPTION_ERROR]	     = EILSEQ,

	[DCCP_RESET_CODE_MANDATORY_ERROR]    = EOPNOTSUPP,

	};



	return code >= DCCP_MAX_RESET_CODES ? 0 : error_code[code];

}



static void dccp_rcv_reset(struct sock *sk, struct sk_buff *skb)

{

	u8 err = dccp_reset_code_convert(dccp_hdr_reset(skb)->dccph_reset_code);



	sk->sk_err = err;



	/* Queue the equivalent of TCP fin so that dccp_recvmsg exits the loop */

	dccp_fin(sk, skb);



	if (err && !sock_flag(sk, SOCK_DEAD))

		sk_wake_async(sk, 0, POLL_ERR);

	dccp_time_wait(sk, DCCP_TIME_WAIT, 0);

}



static void dccp_event_ack_recv(struct sock *sk, struct sk_buff *skb)

{

	struct dccp_sock *dp = dccp_sk(sk);
@@ -192,8 +228,7 @@ static int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb, 
		 *		Set TIMEWAIT timer

		 *		Drop packet and return

		 */

		dccp_fin(sk, skb);

		dccp_time_wait(sk, DCCP_TIME_WAIT, 0);

		dccp_rcv_reset(sk, skb);

		return 0;

	case DCCP_PKT_CLOSEREQ:

		dccp_rcv_closereq(sk, skb);
@@ -521,12 +556,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, 
	 *		Drop packet and return

	*/

	if (dh->dccph_type == DCCP_PKT_RESET) {

		/*

		 * Queue the equivalent of TCP fin so that dccp_recvmsg

		 * exits the loop

		 */

		dccp_fin(sk, skb);

		dccp_time_wait(sk, DCCP_TIME_WAIT, 0);

		dccp_rcv_reset(sk, skb);

		return 0;

		/*

		 *   Step 7: Check for unexpected packet types

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