diff mbox series

[net-next,09/15] sctp: add SCTP_REMOTE_UDP_ENCAPS_PORT sockopt

Message ID ff57fb1ff7c477ff038cebb36e9f0554d26d5915.1601387231.git.lucien.xin@gmail.com
State Superseded
Headers show
Series sctp: Implement RFC6951: UDP Encapsulation of SCTP | expand

Commit Message

Xin Long Sept. 29, 2020, 1:49 p.m. UTC 
This patch is to implement:

  rfc6951#section-6.1: Get or Set the Remote UDP Encapsulation Port Number

with the param of the struct:

  struct sctp_udpencaps {
    sctp_assoc_t sue_assoc_id;
    struct sockaddr_storage sue_address;
    uint16_t sue_port;
  };

the encap_port of sock, assoc or transport can be changed by users,
which also means it allows the different transports of the same asoc
to have different encap_port value.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 include/uapi/linux/sctp.h |   7 +++
 net/sctp/socket.c         | 110 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 117 insertions(+)

Comments

Marcelo Ricardo Leitner Oct. 3, 2020, 4:05 a.m. UTC | #1 
On Tue, Sep 29, 2020 at 09:49:01PM +0800, Xin Long wrote:
...
> +struct sctp_udpencaps {
> +	sctp_assoc_t sue_assoc_id;
> +	struct sockaddr_storage sue_address;
> +	uint16_t sue_port;
> +};
...
> +static int sctp_setsockopt_encap_port(struct sock *sk,
> +				      struct sctp_udpencaps *encap,
> +				      unsigned int optlen)
> +{
> +	struct sctp_association *asoc;
> +	struct sctp_transport *t;
> +
> +	if (optlen != sizeof(*encap))
> +		return -EINVAL;
> +
> +	/* If an address other than INADDR_ANY is specified, and
> +	 * no transport is found, then the request is invalid.
> +	 */
> +	if (!sctp_is_any(sk, (union sctp_addr *)&encap->sue_address)) {
> +		t = sctp_addr_id2transport(sk, &encap->sue_address,
> +					   encap->sue_assoc_id);
> +		if (!t)
> +			return -EINVAL;
> +
> +		t->encap_port = encap->sue_port;
                   ^^^^^^^^^^          ^^^^^^^^

encap_port is defined as __u16 is previous patch, but from RFC:
  sue_port:  The UDP port number in network byte order...

asoc->peer.port is stored in host order, so it makes sense to follow
it here. Then need a htons() here and its counter parts.  It is right
in some parts of the patches already.
Xin Long Oct. 3, 2020, 7:41 a.m. UTC | #2 
On Sat, Oct 3, 2020 at 12:05 PM Marcelo Ricardo Leitner
<marcelo.leitner@gmail.com> wrote:
>
> On Tue, Sep 29, 2020 at 09:49:01PM +0800, Xin Long wrote:
> ...
> > +struct sctp_udpencaps {
> > +     sctp_assoc_t sue_assoc_id;
> > +     struct sockaddr_storage sue_address;
> > +     uint16_t sue_port;
> > +};
> ...
> > +static int sctp_setsockopt_encap_port(struct sock *sk,
> > +                                   struct sctp_udpencaps *encap,
> > +                                   unsigned int optlen)
> > +{
> > +     struct sctp_association *asoc;
> > +     struct sctp_transport *t;
> > +
> > +     if (optlen != sizeof(*encap))
> > +             return -EINVAL;
> > +
> > +     /* If an address other than INADDR_ANY is specified, and
> > +      * no transport is found, then the request is invalid.
> > +      */
> > +     if (!sctp_is_any(sk, (union sctp_addr *)&encap->sue_address)) {
> > +             t = sctp_addr_id2transport(sk, &encap->sue_address,
> > +                                        encap->sue_assoc_id);
> > +             if (!t)
> > +                     return -EINVAL;
> > +
> > +             t->encap_port = encap->sue_port;
>                    ^^^^^^^^^^          ^^^^^^^^
>
> encap_port is defined as __u16 is previous patch, but from RFC:
>   sue_port:  The UDP port number in network byte order...
>
> asoc->peer.port is stored in host order, so it makes sense to follow
> it here. Then need a htons() here and its counter parts.  It is right
> in some parts of the patches already.
Good catch! thank you!
diff mbox series

Patch

diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
index 28ad40d..cb78e7a 100644
--- a/include/uapi/linux/sctp.h
+++ b/include/uapi/linux/sctp.h
@@ -140,6 +140,7 @@  typedef __s32 sctp_assoc_t;
 #define SCTP_ECN_SUPPORTED	130
 #define SCTP_EXPOSE_POTENTIALLY_FAILED_STATE	131
 #define SCTP_EXPOSE_PF_STATE	SCTP_EXPOSE_POTENTIALLY_FAILED_STATE
+#define SCTP_REMOTE_UDP_ENCAPS_PORT	132
 
 /* PR-SCTP policies */
 #define SCTP_PR_SCTP_NONE	0x0000
@@ -1197,6 +1198,12 @@  struct sctp_event {
 	uint8_t se_on;
 };
 
+struct sctp_udpencaps {
+	sctp_assoc_t sue_assoc_id;
+	struct sockaddr_storage sue_address;
+	uint16_t sue_port;
+};
+
 /* SCTP Stream schedulers */
 enum sctp_sched_type {
 	SCTP_SS_FCFS,
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 9aa0c3d..d793dfa9 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -4417,6 +4417,53 @@  static int sctp_setsockopt_pf_expose(struct sock *sk,
 	return retval;
 }
 
+static int sctp_setsockopt_encap_port(struct sock *sk,
+				      struct sctp_udpencaps *encap,
+				      unsigned int optlen)
+{
+	struct sctp_association *asoc;
+	struct sctp_transport *t;
+
+	if (optlen != sizeof(*encap))
+		return -EINVAL;
+
+	/* If an address other than INADDR_ANY is specified, and
+	 * no transport is found, then the request is invalid.
+	 */
+	if (!sctp_is_any(sk, (union sctp_addr *)&encap->sue_address)) {
+		t = sctp_addr_id2transport(sk, &encap->sue_address,
+					   encap->sue_assoc_id);
+		if (!t)
+			return -EINVAL;
+
+		t->encap_port = encap->sue_port;
+		return 0;
+	}
+
+	/* Get association, if assoc_id != SCTP_FUTURE_ASSOC and the
+	 * socket is a one to many style socket, and an association
+	 * was not found, then the id was invalid.
+	 */
+	asoc = sctp_id2assoc(sk, encap->sue_assoc_id);
+	if (!asoc && encap->sue_assoc_id != SCTP_FUTURE_ASSOC &&
+	    sctp_style(sk, UDP))
+		return -EINVAL;
+
+	/* If changes are for association, also apply encap to each
+	 * transport.
+	 */
+	if (asoc) {
+		list_for_each_entry(t, &asoc->peer.transport_addr_list,
+				    transports)
+			t->encap_port = encap->sue_port;
+
+		return 0;
+	}
+
+	sctp_sk(sk)->encap_port = encap->sue_port;
+	return 0;
+}
+
 /* API 6.2 setsockopt(), getsockopt()
  *
  * Applications use setsockopt() and getsockopt() to set or retrieve
@@ -4636,6 +4683,9 @@  static int sctp_setsockopt(struct sock *sk, int level, int optname,
 	case SCTP_EXPOSE_POTENTIALLY_FAILED_STATE:
 		retval = sctp_setsockopt_pf_expose(sk, kopt, optlen);
 		break;
+	case SCTP_REMOTE_UDP_ENCAPS_PORT:
+		retval = sctp_setsockopt_encap_port(sk, kopt, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;
@@ -7791,6 +7841,63 @@  static int sctp_getsockopt_pf_expose(struct sock *sk, int len,
 	return retval;
 }
 
+static int sctp_getsockopt_encap_port(struct sock *sk, int len,
+				      char __user *optval, int __user *optlen)
+{
+	struct sctp_association *asoc;
+	struct sctp_udpencaps encap;
+	struct sctp_transport *t;
+
+	if (len < sizeof(encap))
+		return -EINVAL;
+
+	len = sizeof(encap);
+	if (copy_from_user(&encap, optval, len))
+		return -EFAULT;
+
+	/* If an address other than INADDR_ANY is specified, and
+	 * no transport is found, then the request is invalid.
+	 */
+	if (!sctp_is_any(sk, (union sctp_addr *)&encap.sue_address)) {
+		t = sctp_addr_id2transport(sk, &encap.sue_address,
+					   encap.sue_assoc_id);
+		if (!t) {
+			pr_debug("%s: failed no transport\n", __func__);
+			return -EINVAL;
+		}
+
+		encap.sue_port = t->encap_port;
+		goto out;
+	}
+
+	/* Get association, if assoc_id != SCTP_FUTURE_ASSOC and the
+	 * socket is a one to many style socket, and an association
+	 * was not found, then the id was invalid.
+	 */
+	asoc = sctp_id2assoc(sk, encap.sue_assoc_id);
+	if (!asoc && encap.sue_assoc_id != SCTP_FUTURE_ASSOC &&
+	    sctp_style(sk, UDP)) {
+		pr_debug("%s: failed no association\n", __func__);
+		return -EINVAL;
+	}
+
+	if (asoc) {
+		encap.sue_port = asoc->encap_port;
+		goto out;
+	}
+
+	encap.sue_port = sctp_sk(sk)->encap_port;
+
+out:
+	if (copy_to_user(optval, &encap, len))
+		return -EFAULT;
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+
+	return 0;
+}
+
 static int sctp_getsockopt(struct sock *sk, int level, int optname,
 			   char __user *optval, int __user *optlen)
 {
@@ -8011,6 +8118,9 @@  static int sctp_getsockopt(struct sock *sk, int level, int optname,
 	case SCTP_EXPOSE_POTENTIALLY_FAILED_STATE:
 		retval = sctp_getsockopt_pf_expose(sk, len, optval, optlen);
 		break;
+	case SCTP_REMOTE_UDP_ENCAPS_PORT:
+		retval = sctp_getsockopt_encap_port(sk, len, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;