From: mvs <mvs@openbsd.org>
Date: Sun, 13 Nov 2022 16:01:32 +0000 (+0000)
Subject: Split out handlers for SOCK_DGRAM unix(4) sockets from SOCK_STREAM and
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=67a10ba2366df7017b776ada734f425cd14cc7b0;p=openbsd

Split out handlers for SOCK_DGRAM unix(4) sockets from SOCK_STREAM and
SOCK_SEQPACKET. Introduce `uipc_dgram_usrreqs' to store pointers for
dgram specific handlers.

The dgram pru_shutdown and pru_send handlers were splitted to
uipc_dgram_shutdown() and uipc_dgram_send(). The pru_accept, pru_rcvd
and pru_abort handlers are not required for dgram sockets.

The unp_disconnect() remains shared between all unix(4) sockets because
it called from common paths too.

Proposed by and ok guenther@
---

diff --git a/sys/kern/uipc_proto.c b/sys/kern/uipc_proto.c
index d6447bf9958..ba6259566f7 100644
--- a/sys/kern/uipc_proto.c
+++ b/sys/kern/uipc_proto.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uipc_proto.c,v 1.24 2022/08/15 09:11:38 mvs Exp $	*/
+/*	$OpenBSD: uipc_proto.c,v 1.25 2022/11/13 16:01:32 mvs Exp $	*/
 /*	$NetBSD: uipc_proto.c,v 1.8 1996/02/13 21:10:47 christos Exp $	*/
 
 /*-
@@ -62,7 +62,7 @@ const struct protosw unixsw[] = {
   .pr_domain	= &unixdomain,
   .pr_protocol	= PF_UNIX,
   .pr_flags	= PR_ATOMIC|PR_ADDR|PR_RIGHTS,
-  .pr_usrreqs	= &uipc_usrreqs,
+  .pr_usrreqs	= &uipc_dgram_usrreqs,
 }
 };
 
diff --git a/sys/kern/uipc_usrreq.c b/sys/kern/uipc_usrreq.c
index 38f4d073198..51edacb135d 100644
--- a/sys/kern/uipc_usrreq.c
+++ b/sys/kern/uipc_usrreq.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uipc_usrreq.c,v 1.191 2022/10/17 14:49:01 mvs Exp $	*/
+/*	$OpenBSD: uipc_usrreq.c,v 1.192 2022/11/13 16:01:32 mvs Exp $	*/
 /*	$NetBSD: uipc_usrreq.c,v 1.18 1996/02/09 19:00:50 christos Exp $	*/
 
 /*
@@ -144,6 +144,21 @@ const struct pr_usrreqs uipc_usrreqs = {
 	.pru_connect2	= uipc_connect2,
 };
 
+const struct pr_usrreqs uipc_dgram_usrreqs = {
+	.pru_attach	= uipc_attach,
+	.pru_detach	= uipc_detach,
+	.pru_bind	= uipc_bind,
+	.pru_listen	= uipc_listen,
+	.pru_connect	= uipc_connect,
+	.pru_disconnect	= uipc_disconnect,
+	.pru_shutdown	= uipc_dgram_shutdown,
+	.pru_send	= uipc_dgram_send,
+	.pru_sense	= uipc_sense,
+	.pru_sockaddr	= uipc_sockaddr,
+	.pru_peeraddr	= uipc_peeraddr,
+	.pru_connect2	= uipc_connect2,
+};
+
 void
 unp_init(void)
 {
@@ -358,9 +373,22 @@ int
 uipc_shutdown(struct socket *so)
 {
 	struct unpcb *unp = sotounpcb(so);
+	struct socket *so2;
+
+	socantsendmore(so);
+
+	if ((so2 = unp_solock_peer(unp->unp_socket))){
+		socantrcvmore(so2);
+		sounlock(so2);
+	}
+
+	return (0);
+}
 
+int
+uipc_dgram_shutdown(struct socket *so)
+{
 	socantsendmore(so);
-	unp_shutdown(unp);
 	return (0);
 }
 
@@ -369,35 +397,22 @@ uipc_rcvd(struct socket *so)
 {
 	struct socket *so2;
 
-	switch (so->so_type) {
-	case SOCK_DGRAM:
-		panic("uipc 1");
-		/*NOTREACHED*/
-
-	case SOCK_STREAM:
-	case SOCK_SEQPACKET:
-		if ((so2 = unp_solock_peer(so)) == NULL)
-			break;
-		/*
-		 * Adjust backpressure on sender
-		 * and wakeup any waiting to write.
-		 */
-		so2->so_snd.sb_mbcnt = so->so_rcv.sb_mbcnt;
-		so2->so_snd.sb_cc = so->so_rcv.sb_cc;
-		sowwakeup(so2);
-		sounlock(so2);
-		break;
-
-	default:
-		panic("uipc 2");
-	}
+	if ((so2 = unp_solock_peer(so)) == NULL)
+		return;
+	/*
+	 * Adjust backpressure on sender
+	 * and wakeup any waiting to write.
+	 */
+	so2->so_snd.sb_mbcnt = so->so_rcv.sb_mbcnt;
+	so2->so_snd.sb_cc = so->so_rcv.sb_cc;
+	sowwakeup(so2);
+	sounlock(so2);
 }
 
 int
 uipc_send(struct socket *so, struct mbuf *m, struct mbuf *nam,
     struct mbuf *control)
 {
-	struct unpcb *unp = sotounpcb(so);
 	struct socket *so2;
 	int error = 0;
 
@@ -409,88 +424,105 @@ uipc_send(struct socket *so, struct mbuf *m, struct mbuf *nam,
 			goto out;
 	}
 
-	switch (so->so_type) {
-	case SOCK_DGRAM: {
-		const struct sockaddr *from;
+	if (so->so_state & SS_CANTSENDMORE) {
+		error = EPIPE;
+		goto dispose;
+	}
+	if ((so2 = unp_solock_peer(so)) == NULL) {
+		error = ENOTCONN;
+		goto dispose;
+	}
 
-		if (nam) {
-			if (unp->unp_conn) {
-				error = EISCONN;
-				break;
-			}
-			error = unp_connect(so, nam, curproc);
-			if (error)
-				break;
+	/*
+	 * Send to paired receive port, and then raise
+	 * send buffer counts to maintain backpressure.
+	 * Wake up readers.
+	 */
+	if (control) {
+		if (sbappendcontrol(so2, &so2->so_rcv, m, control)) {
+			control = NULL;
+		} else {
+			sounlock(so2);
+			error = ENOBUFS;
+			goto dispose;
 		}
+	} else if (so->so_type == SOCK_SEQPACKET)
+		sbappendrecord(so2, &so2->so_rcv, m);
+	else
+		sbappend(so2, &so2->so_rcv, m);
+	so->so_snd.sb_mbcnt = so2->so_rcv.sb_mbcnt;
+	so->so_snd.sb_cc = so2->so_rcv.sb_cc;
+	if (so2->so_rcv.sb_cc > 0)
+		sorwakeup(so2);
 
-		if ((so2 = unp_solock_peer(so)) == NULL) {
-			if (nam != NULL)
-				error = ECONNREFUSED;
-			else
-				error = ENOTCONN;
-			break;
-		}
+	sounlock(so2);
+	m = NULL;
 
-		if (unp->unp_addr)
-			from = mtod(unp->unp_addr, struct sockaddr *);
-		else
-			from = &sun_noname;
-		if (sbappendaddr(so2, &so2->so_rcv, from, m, control)) {
-			sorwakeup(so2);
-			m = NULL;
-			control = NULL;
-		} else
-			error = ENOBUFS;
+dispose:
+	/* we need to undo unp_internalize in case of errors */
+	if (control && error)
+		unp_dispose(control);
 
-		if (so2 != so)
-			sounlock(so2);
+out:
+	m_freem(control);
+	m_freem(m);
 
-		if (nam)
-			unp_disconnect(unp);
-		break;
+	return (error);
+}
+
+int
+uipc_dgram_send(struct socket *so, struct mbuf *m, struct mbuf *nam,
+    struct mbuf *control)
+{
+	struct unpcb *unp = sotounpcb(so);
+	struct socket *so2;
+	const struct sockaddr *from;
+	int error = 0;
+
+	if (control) {
+		sounlock(so);
+		error = unp_internalize(control, curproc);
+		solock(so);
+		if (error)
+			goto out;
 	}
 
-	case SOCK_STREAM:
-	case SOCK_SEQPACKET:
-		if (so->so_state & SS_CANTSENDMORE) {
-			error = EPIPE;
-			break;
-		}
-		if ((so2 = unp_solock_peer(so)) == NULL) {
-			error = ENOTCONN;
-			break;
+	if (nam) {
+		if (unp->unp_conn) {
+			error = EISCONN;
+			goto dispose;
 		}
+		error = unp_connect(so, nam, curproc);
+		if (error)
+			goto dispose;
+	}
 
-		/*
-		 * Send to paired receive port, and then raise
-		 * send buffer counts to maintain backpressure.
-		 * Wake up readers.
-		 */
-		if (control) {
-			if (sbappendcontrol(so2, &so2->so_rcv, m, control)) {
-				control = NULL;
-			} else {
-				sounlock(so2);
-				error = ENOBUFS;
-				break;
-			}
-		} else if (so->so_type == SOCK_SEQPACKET)
-			sbappendrecord(so2, &so2->so_rcv, m);
+	if ((so2 = unp_solock_peer(so)) == NULL) {
+		if (nam != NULL)
+			error = ECONNREFUSED;
 		else
-			sbappend(so2, &so2->so_rcv, m);
-		so->so_snd.sb_mbcnt = so2->so_rcv.sb_mbcnt;
-		so->so_snd.sb_cc = so2->so_rcv.sb_cc;
-		if (so2->so_rcv.sb_cc > 0)
-			sorwakeup(so2);
+			error = ENOTCONN;
+		goto dispose;
+	}
 
-		sounlock(so2);
+	if (unp->unp_addr)
+		from = mtod(unp->unp_addr, struct sockaddr *);
+	else
+		from = &sun_noname;
+	if (sbappendaddr(so2, &so2->so_rcv, from, m, control)) {
+		sorwakeup(so2);
 		m = NULL;
-		break;
+		control = NULL;
+	} else
+		error = ENOBUFS;
 
-	default:
-		panic("uipc 4");
-	}
+	if (so2 != so)
+		sounlock(so2);
 
+	if (nam)
+		unp_disconnect(unp);
+
+dispose:
 	/* we need to undo unp_internalize in case of errors */
 	if (control && error)
 		unp_dispose(control);
@@ -975,26 +1007,6 @@ unp_disconnect(struct unpcb *unp)
 		sounlock(so2);
 }
 
-void
-unp_shutdown(struct unpcb *unp)
-{
-	struct socket *so2;
-
-	switch (unp->unp_socket->so_type) {
-	case SOCK_STREAM:
-	case SOCK_SEQPACKET:
-		if ((so2 = unp_solock_peer(unp->unp_socket)) == NULL)
-			break;
-		
-		socantrcvmore(so2);
-		sounlock(so2);
-
-		break;
-	default:
-		break;
-	}
-}
-
 static struct unpcb *
 fptounp(struct file *fp)
 {
diff --git a/sys/sys/unpcb.h b/sys/sys/unpcb.h
index 03f4cbb9e55..c71617ef7cd 100644
--- a/sys/sys/unpcb.h
+++ b/sys/sys/unpcb.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: unpcb.h,v 1.43 2022/10/17 14:49:02 mvs Exp $	*/
+/*	$OpenBSD: unpcb.h,v 1.44 2022/11/13 16:01:32 mvs Exp $	*/
 /*	$NetBSD: unpcb.h,v 1.6 1994/06/29 06:46:08 cgd Exp $	*/
 
 /*
@@ -111,6 +111,7 @@ struct fdpass {
 };
 
 extern const struct pr_usrreqs uipc_usrreqs;
+extern const struct pr_usrreqs uipc_dgram_usrreqs;
 
 int	uipc_attach(struct socket *, int, int);
 int	uipc_detach(struct socket *);
@@ -120,9 +121,12 @@ int	uipc_connect(struct socket *, struct mbuf *);
 int	uipc_accept(struct socket *, struct mbuf *);
 int	uipc_disconnect(struct socket *);
 int	uipc_shutdown(struct socket *);
+int	uipc_dgram_shutdown(struct socket *);
 void	uipc_rcvd(struct socket *);
 int	uipc_send(struct socket *, struct mbuf *, struct mbuf *,
 	    struct mbuf *);
+int	uipc_dgram_send(struct socket *, struct mbuf *, struct mbuf *,
+	    struct mbuf *);
 void	uipc_abort(struct socket *);
 int	uipc_sense(struct socket *, struct stat *);
 int	uipc_sockaddr(struct socket *, struct mbuf *);
@@ -136,7 +140,6 @@ int	unp_connect2(struct socket *, struct socket *);
 void	unp_detach(struct unpcb *);
 void	unp_disconnect(struct unpcb *);
 void	unp_gc(void *);
-void	unp_shutdown(struct unpcb *);
 int 	unp_externalize(struct mbuf *, socklen_t, int);
 int	unp_internalize(struct mbuf *, struct proc *);
 void 	unp_dispose(struct mbuf *);