Merge branch 'sctp-add-SCTP_ECN_SUPPORTED-sockopt'

Xin Long says:

====================
sctp: add SCTP_ECN_SUPPORTED sockopt

This patchset is to make ecn flag per netns and endpoint and then
add SCTP_ECN_SUPPORTED sockopt, as does for other feature flags.
====================

Acked-by: Neil Horman <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: davem330

include/net/netns/sctp.h

@@ -128,6 +128,9 @@ struct netns_sctp {
 	/* Flag to indicate if stream interleave is enabled */
 	int intl_enable;
 
+	/* Flag to indicate if ecn is enabled */
+	int ecn_enable;
+
 	/*
 	 * Policy to control SCTP IPv4 address scoping
 	 * 0   - Disable IPv4 address scoping

include/net/sctp/structs.h

@@ -1322,7 +1322,8 @@ struct sctp_endpoint {
 	/* SCTP-AUTH: endpoint shared keys */
 	struct list_head endpoint_shared_keys;
 	__u16 active_key_id;
-	__u8  auth_enable:1,
+	__u8  ecn_enable:1,
+	      auth_enable:1,
 	      intl_enable:1,
 	      prsctp_enable:1,
 	      asconf_enable:1,

include/uapi/linux/sctp.h

@@ -136,6 +136,7 @@ typedef __s32 sctp_assoc_t;
 #define SCTP_EVENT	127
 #define SCTP_ASCONF_SUPPORTED	128
 #define SCTP_AUTH_SUPPORTED	129
+#define SCTP_ECN_SUPPORTED	130
 
 /* PR-SCTP policies */
 #define SCTP_PR_SCTP_NONE	0x0000

net/sctp/endpointola.c

@@ -106,6 +106,7 @@ static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
 	 */
 	ep->prsctp_enable = net->sctp.prsctp_enable;
 	ep->reconf_enable = net->sctp.reconf_enable;
+	ep->ecn_enable = net->sctp.ecn_enable;
 
 	/* Remember who we are attached to.  */
 	ep->base.sk = sk;

net/sctp/protocol.c

@@ -1254,6 +1254,9 @@ static int __net_init sctp_defaults_init(struct net *net)
 	/* Disable AUTH by default. */
 	net->sctp.auth_enable = 0;
 
+	/* Enable ECN by default. */
+	net->sctp.ecn_enable = 1;
+
 	/* Set SCOPE policy to enabled */
 	net->sctp.scope_policy = SCTP_SCOPE_POLICY_ENABLE;
 

net/sctp/sm_make_chunk.c

@@ -244,7 +244,9 @@ struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
 
 	chunksize = sizeof(init) + addrs_len;
 	chunksize += SCTP_PAD4(SCTP_SAT_LEN(num_types));
-	chunksize += sizeof(ecap_param);
+
+	if (asoc->ep->ecn_enable)
+		chunksize += sizeof(ecap_param);
 
 	if (asoc->ep->prsctp_enable)
 		chunksize += sizeof(prsctp_param);
@@ -335,7 +337,8 @@ struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
 	sctp_addto_chunk(retval, sizeof(sat), &sat);
 	sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
 
-	sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
+	if (asoc->ep->ecn_enable)
+		sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
 
 	/* Add the supported extensions parameter.  Be nice and add this
 	 * fist before addiding the parameters for the extensions themselves
@@ -2597,8 +2600,13 @@ static int sctp_process_param(struct sctp_association *asoc,
 		break;
 
 	case SCTP_PARAM_ECN_CAPABLE:
-		asoc->peer.ecn_capable = 1;
-		break;
+		if (asoc->ep->ecn_enable) {
+			asoc->peer.ecn_capable = 1;
+			break;
+		}
+		/* Fall Through */
+		goto fall_through;
+
 
 	case SCTP_PARAM_ADAPTATION_LAYER_IND:
 		asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);

net/sctp/socket.c

@@ -4560,6 +4560,34 @@ static int sctp_setsockopt_auth_supported(struct sock *sk,
 	return retval;
 }
 
+static int sctp_setsockopt_ecn_supported(struct sock *sk,
+					 char __user *optval,
+					 unsigned int optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EINVAL;
+
+	if (optlen != sizeof(params))
+		goto out;
+
+	if (copy_from_user(&params, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC &&
+	    sctp_style(sk, UDP))
+		goto out;
+
+	sctp_sk(sk)->ep->ecn_enable = !!params.assoc_value;
+	retval = 0;
+
+out:
+	return retval;
+}
+
 /* API 6.2 setsockopt(), getsockopt()
  *
  * Applications use setsockopt() and getsockopt() to set or retrieve
@@ -4766,6 +4794,9 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
 	case SCTP_AUTH_SUPPORTED:
 		retval = sctp_setsockopt_auth_supported(sk, optval, optlen);
 		break;
+	case SCTP_ECN_SUPPORTED:
+		retval = sctp_setsockopt_ecn_supported(sk, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;
@@ -7828,6 +7859,45 @@ static int sctp_getsockopt_auth_supported(struct sock *sk, int len,
 	return retval;
 }
 
+static int sctp_getsockopt_ecn_supported(struct sock *sk, int len,
+					 char __user *optval,
+					 int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EFAULT;
+
+	if (len < sizeof(params)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC &&
+	    sctp_style(sk, UDP)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	params.assoc_value = asoc ? asoc->peer.ecn_capable
+				  : sctp_sk(sk)->ep->ecn_enable;
+
+	if (put_user(len, optlen))
+		goto out;
+
+	if (copy_to_user(optval, &params, len))
+		goto out;
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
 static int sctp_getsockopt(struct sock *sk, int level, int optname,
 			   char __user *optval, int __user *optlen)
 {
@@ -8037,6 +8107,9 @@ static int sctp_getsockopt(struct sock *sk, int level, int optname,
 		retval = sctp_getsockopt_auth_supported(sk, len, optval,
 							optlen);
 		break;
+	case SCTP_ECN_SUPPORTED:
+		retval = sctp_getsockopt_ecn_supported(sk, len, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;

net/sctp/sysctl.c

@@ -277,6 +277,13 @@ static struct ctl_table sctp_net_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 	},
+	{
+		.procname	= "ecn_enable",
+		.data		= &init_net.sctp.ecn_enable,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
 	{
 		.procname	= "addr_scope_policy",
 		.data		= &init_net.sctp.scope_policy,