Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 44b1e6b5 authored by Hendrik Brueckner's avatar Hendrik Brueckner Committed by David S. Miller
Browse files

af_iucv: Modify iucv msg target class using control msghdr 



Allow 'classification' of socket data that is sent or received over
an af_iucv socket. For classification of data, the target class of an
(native) iucv message is used.

This patch provides the cmsg interface for iucv_sock_recvmsg() and
iucv_sock_sendmsg().  Applications can use the msg_control field of
struct msghdr to set or get the target class as a
"socket control message" (SCM/CMSG).

Signed-off-by: default avatarHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: default avatarUrsula Braun <ursula.braun@de.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent b8942e3b

include/net/iucv/af_iucv.h

+3 −0
Original line number Original line Diff line number Diff line
@@ -79,6 +79,9 @@ struct iucv_sock { 
/* iucv socket options (SOL_IUCV) */

/* iucv socket options (SOL_IUCV) */

#define SO_IPRMDATA_MSG	0x0080		/* send/recv IPRM_DATA msgs */

#define SO_IPRMDATA_MSG	0x0080		/* send/recv IPRM_DATA msgs */





/* iucv related control messages (scm) */

#define SCM_IUCV_TRGCLS	0x0001		/* target class control message */



struct iucv_sock_list {

struct iucv_sock_list {

	struct hlist_head head;

	struct hlist_head head;

	rwlock_t	  lock;

	rwlock_t	  lock;

net/iucv/af_iucv.c

+75 −4
Original line number Original line Diff line number Diff line
@@ -45,6 +45,15 @@ static struct proto iucv_proto = { 
static const u8 iprm_shutdown[8] =

static const u8 iprm_shutdown[8] =

	{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};

	{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};





#define TRGCLS_SIZE	(sizeof(((struct iucv_message *)0)->class))



/* macros to set/get socket control buffer at correct offset */

#define CB_TAG(skb)	((skb)->cb)		/* iucv message tag */

#define CB_TAG_LEN	(sizeof(((struct iucv_message *) 0)->tag))

#define CB_TRGCLS(skb)	((skb)->cb + CB_TAG_LEN) /* iucv msg target class */

#define CB_TRGCLS_LEN	(TRGCLS_SIZE)





static void iucv_sock_kill(struct sock *sk);

static void iucv_sock_kill(struct sock *sk);

static void iucv_sock_close(struct sock *sk);

static void iucv_sock_close(struct sock *sk);
@@ -698,6 +707,8 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock, 
	struct iucv_sock *iucv = iucv_sk(sk);

	struct iucv_sock *iucv = iucv_sk(sk);

	struct sk_buff *skb;

	struct sk_buff *skb;

	struct iucv_message txmsg;

	struct iucv_message txmsg;

	struct cmsghdr *cmsg;

	int cmsg_done;

	char user_id[9];

	char user_id[9];

	char appl_id[9];

	char appl_id[9];

	int err;

	int err;
@@ -717,6 +728,48 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock, 
	}

	}





	if (sk->sk_state == IUCV_CONNECTED) {

	if (sk->sk_state == IUCV_CONNECTED) {

		/* initialize defaults */

		cmsg_done   = 0;	/* check for duplicate headers */

		txmsg.class = 0;



		/* iterate over control messages */

		for (cmsg = CMSG_FIRSTHDR(msg); cmsg;

		     cmsg = CMSG_NXTHDR(msg, cmsg)) {



			if (!CMSG_OK(msg, cmsg)) {

				err = -EINVAL;

				goto out;

			}



			if (cmsg->cmsg_level != SOL_IUCV)

				continue;



			if (cmsg->cmsg_type & cmsg_done) {

				err = -EINVAL;

				goto out;

			}

			cmsg_done |= cmsg->cmsg_type;



			switch (cmsg->cmsg_type) {

			case SCM_IUCV_TRGCLS:

				if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {

					err = -EINVAL;

					goto out;

				}



				/* set iucv message target class */

				memcpy(&txmsg.class,

					(void *) CMSG_DATA(cmsg), TRGCLS_SIZE);



				break;



			default:

				err = -EINVAL;

				goto out;

				break;

			}

		}



		if (!(skb = sock_alloc_send_skb(sk, len,

		if (!(skb = sock_alloc_send_skb(sk, len,

						msg->msg_flags & MSG_DONTWAIT,

						msg->msg_flags & MSG_DONTWAIT,

						&err)))

						&err)))
@@ -727,10 +780,9 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock, 
			goto fail;

			goto fail;

		}

		}





		txmsg.class = 0;

		/* increment and save iucv message tag for msg_completion cbk */

		memcpy(&txmsg.class, skb->data, skb->len >= 4 ? 4 : skb->len);

		txmsg.tag = iucv->send_tag++;

		txmsg.tag = iucv->send_tag++;

		memcpy(skb->cb, &txmsg.tag, 4);

		memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);

		skb_queue_tail(&iucv->send_skb_q, skb);

		skb_queue_tail(&iucv->send_skb_q, skb);





		if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)

		if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
@@ -801,6 +853,10 @@ static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len) 
		if (!nskb)

		if (!nskb)

			return -ENOMEM;

			return -ENOMEM;





		/* copy target class to control buffer of new skb */

		memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);



		/* copy data fragment */

		memcpy(nskb->data, skb->data + copied, size);

		memcpy(nskb->data, skb->data + copied, size);

		copied += size;

		copied += size;

		dataleft -= size;

		dataleft -= size;
@@ -824,6 +880,10 @@ static void iucv_process_message(struct sock *sk, struct sk_buff *skb, 




	len = iucv_msg_length(msg);

	len = iucv_msg_length(msg);





	/* store msg target class in the second 4 bytes of skb ctrl buffer */

	/* Note: the first 4 bytes are reserved for msg tag */

	memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);



	/* check for special IPRM messages (e.g. iucv_sock_shutdown) */

	/* check for special IPRM messages (e.g. iucv_sock_shutdown) */

	if ((msg->flags & IUCV_IPRMDATA) && len > 7) {

	if ((msg->flags & IUCV_IPRMDATA) && len > 7) {

		if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {

		if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
@@ -915,6 +975,17 @@ static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock, 




	len -= copied;

	len -= copied;





	/* create control message to store iucv msg target class:

	 * get the trgcls from the control buffer of the skb due to

	 * fragmentation of original iucv message. */

	err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,

			CB_TRGCLS_LEN, CB_TRGCLS(skb));

	if (err) {

		if (!(flags & MSG_PEEK))

			skb_queue_head(&sk->sk_receive_queue, skb);

		return err;

	}



	/* Mark read part of skb as used */

	/* Mark read part of skb as used */

	if (!(flags & MSG_PEEK)) {

	if (!(flags & MSG_PEEK)) {

		skb_pull(skb, copied);

		skb_pull(skb, copied);
@@ -1316,7 +1387,7 @@ static void iucv_callback_txdone(struct iucv_path *path, 
		spin_lock_irqsave(&list->lock, flags);

		spin_lock_irqsave(&list->lock, flags);





		while (list_skb != (struct sk_buff *)list) {

		while (list_skb != (struct sk_buff *)list) {

			if (!memcmp(&msg->tag, list_skb->cb, 4)) {

			if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {

				this = list_skb;

				this = list_skb;

				break;

				break;

			}

			}