Add ktracing of structs iovec, msghdr, and cmsghdr for {,p}{read,write}v(),

sendmsg(), and recvmsg().  For cmsghdr, the len, level, and type are always
shown, and for SOL_SOCKET,SCM_RIGHTS the fd numbers being passed are shown.

ok millert@ deraadt@

4 files changed, 141 insertions, 4 deletions

diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c
index b6752bb5c40..d1c89d52c98 100644
--- a/sys/kern/sys_generic.c
+++ b/sys/kern/sys_generic.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sys_generic.c,v 1.99 2015/07/19 02:35:35 deraadt Exp $	*/
+/*	$OpenBSD: sys_generic.c,v 1.100 2015/07/28 05:50:41 guenther Exp $	*/
 /*	$NetBSD: sys_generic.c,v 1.24 1996/03/29 00:25:32 cgd Exp $	*/
 
 /*
@@ -161,6 +161,10 @@ dofilereadv(struct proc *p, int fd, struct file *fp, const struct iovec *iovp,
 		}
 		if ((error = copyin(iovp, iov, iovlen)))
 			goto done;
+#ifdef KTRACE
+		if (KTRPOINT(p, KTR_STRUCT))
+			ktriovec(p, iov, iovcnt);
+#endif
 	} else {
 		iov = (struct iovec *)iovp;		/* de-constify */
 	}
@@ -309,6 +313,10 @@ dofilewritev(struct proc *p, int fd, struct file *fp, const struct iovec *iovp,
 		}
 		if ((error = copyin(iovp, iov, iovlen)))
 			goto done;
+#ifdef KTRACE
+		if (KTRPOINT(p, KTR_STRUCT))
+			ktriovec(p, iov, iovcnt);
+#endif
 	} else {
 		iov = (struct iovec *)iovp;		/* de-constify */
 	}
diff --git a/sys/kern/uipc_syscalls.c b/sys/kern/uipc_syscalls.c
index 74ae41e2910..9b785a06559 100644
--- a/sys/kern/uipc_syscalls.c
+++ b/sys/kern/uipc_syscalls.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uipc_syscalls.c,v 1.105 2015/07/27 04:01:51 guenther Exp $	*/
+/*	$OpenBSD: uipc_syscalls.c,v 1.106 2015/07/28 05:50:41 guenther Exp $	*/
 /*	$NetBSD: uipc_syscalls.c,v 1.19 1996/02/09 19:00:48 christos Exp $	*/
 
 /*
@@ -494,6 +494,10 @@ sys_sendmsg(struct proc *p, void *v, register_t *retval)
 	error = copyin(SCARG(uap, msg), &msg, sizeof (msg));
 	if (error)
 		return (error);
+#ifdef KTRACE
+	if (KTRPOINT(p, KTR_STRUCT))
+		ktrmsghdr(p, &msg);
+#endif
 
 	if (tame_sendto_check(p, msg.msg_name))
 		return (tame_fail(p, EPERM, _TM_UNIX));
@@ -509,6 +513,10 @@ sys_sendmsg(struct proc *p, void *v, register_t *retval)
 	    (error = copyin(msg.msg_iov, iov,
 		    (unsigned)(msg.msg_iovlen * sizeof (struct iovec)))))
 		goto done;
+#ifdef KTRACE
+	if (msg.msg_iovlen && KTRPOINT(p, KTR_STRUCT))
+		ktriovec(p, iov, msg.msg_iovlen);
+#endif
 	msg.msg_iov = iov;
 	msg.msg_flags = 0;
 	error = sendit(p, SCARG(uap, s), &msg, SCARG(uap, flags), retval);
@@ -572,6 +580,11 @@ sendit(struct proc *p, int s, struct msghdr *mp, int flags, register_t *retsize)
 		    mp->msg_controllen, MT_CONTROL);
 		if (error)
 			goto bad;
+#ifdef KTRACE
+		if (KTRPOINT(p, KTR_STRUCT) && mp->msg_controllen)
+			ktrcmsghdr(p, mtod(control, char *),
+			    mp->msg_controllen);
+#endif
 
 		if (tame_cmsg_send(p, control, mp->msg_controllen)) {
 			m_free(control);
@@ -689,6 +702,13 @@ sys_recvmsg(struct proc *p, void *v, register_t *retval)
 	msg.msg_iov = iov;
 	if ((error = recvit(p, SCARG(uap, s), &msg, NULL, retval)) == 0) {
 		msg.msg_iov = uiov;
+#ifdef KTRACE
+		if (KTRPOINT(p, KTR_STRUCT)) {
+			ktrmsghdr(p, &msg);
+			if (msg.msg_iovlen)
+				ktriovec(p, iov, msg.msg_iovlen);
+		}
+#endif
 		error = copyout(&msg, SCARG(uap, msg), sizeof(msg));
 	}
 done:
@@ -790,6 +810,10 @@ recvit(struct proc *p, int s, struct msghdr *mp, caddr_t namelenp,
 			struct mbuf *m = control;
 			caddr_t cp = mp->msg_control;
 
+#ifdef KTRACE
+			if (KTRPOINT(p, KTR_STRUCT) && len)
+				ktrcmsghdr(p, mtod(control, char *), len);
+#endif
 			do {
 				i = m->m_len;
 				if (len < i) {
diff --git a/sys/sys/ktrace.h b/sys/sys/ktrace.h
index 846eafd15ca..94fd788e6f7 100644
--- a/sys/sys/ktrace.h
+++ b/sys/sys/ktrace.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ktrace.h,v 1.22 2015/07/19 04:45:25 guenther Exp $	*/
+/*	$OpenBSD: ktrace.h,v 1.23 2015/07/28 05:50:41 guenther Exp $	*/
 /*	$NetBSD: ktrace.h,v 1.12 1996/02/04 02:12:29 christos Exp $	*/
 
 /*
@@ -234,5 +234,11 @@ void    ktrstruct(struct proc *, const char *, const void *, size_t);
 	ktrstruct((p), "fdset", (s), l)
 #define ktrquota(p, s) \
 	ktrstruct((p), "quota", (s), sizeof(struct dqblk))
+#define ktrmsghdr(p, s) \
+	ktrstruct(p, "msghdr", s, sizeof(struct msghdr))
+#define ktriovec(p, s, count) \
+	ktrstruct(p, "iovec", s, (count) * sizeof(struct iovec))
+#define ktrcmsghdr(p, c, len) \
+	ktrstruct(p, "cmsghdr", c, len)
 
 #endif	/* !_KERNEL */
diff --git a/usr.bin/kdump/ktrstruct.c b/usr.bin/kdump/ktrstruct.c
index b218ee2027e..2fc328d7c68 100644
--- a/usr.bin/kdump/ktrstruct.c
+++ b/usr.bin/kdump/ktrstruct.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ktrstruct.c,v 1.9 2014/12/16 03:19:23 jsg Exp $	*/
+/*	$OpenBSD: ktrstruct.c,v 1.10 2015/07/28 05:50:41 guenther Exp $	*/
 
 /*-
  * Copyright (c) 1988, 1993
@@ -42,6 +42,7 @@
 #include <ctype.h>
 #include <err.h>
 #include <limits.h>
+#include <netdb.h>
 #include <poll.h>
 #include <signal.h>
 #include <stdio.h>
@@ -364,6 +365,84 @@ ktrquota(const struct dqblk *quota)
 	printf(" }\n");
 }
 
+static void
+ktrmsghdr(const struct msghdr *msg)
+{
+	printf("struct msghdr { name=%p, namelen=%u, iov=%p, iovlen=%u,"
+	    " control=%p, controllen=%u, flags=%d }\n",
+	    msg->msg_name, msg->msg_namelen, msg->msg_iov, msg->msg_iovlen,
+	    msg->msg_control, msg->msg_controllen, msg->msg_flags);
+}
+
+static void
+ktriovec(const char *data, int count)
+{
+	struct iovec iov;
+	int i;
+
+	printf("struct iovec");
+	if (count > 1)
+		printf(" [%d]", count);
+	for (i = 0; i < count; i++) {
+		memcpy(&iov, data, sizeof(iov));
+		data += sizeof(iov);
+		printf(" { base=%p, len=%lu }", iov.iov_base, iov.iov_len);
+	}
+	printf("\n");
+}
+
+static void
+ktrcmsghdr(char *data, socklen_t len)
+{
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	int i, count, *fds;
+
+	msg.msg_control = data;
+	msg.msg_controllen = len;
+
+	/* count the control messages */
+	count = 0;
+	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
+	     cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+		count++;
+	}
+
+	printf("struct cmsghdr");
+	if (count > 1)
+		printf(" [%d]", count);
+
+	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
+	     cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+		printf(" { len=%u, level=", cmsg->cmsg_len);
+		if (cmsg->cmsg_level == SOL_SOCKET) {
+			printf("SOL_SOCKET, type=");
+			switch (cmsg->cmsg_type) {
+			case SCM_RIGHTS:
+				printf("SCM_RIGHTS, data=");
+				fds = (int *)CMSG_DATA(cmsg);
+				for (i = 0;
+				    cmsg->cmsg_len > CMSG_LEN(sizeof(int) * i);
+				    i++) {
+					printf("%s%d", i ? "," : "", fds[i]);
+				}
+				break;
+			case SCM_TIMESTAMP:
+			default:
+				printf("%d", cmsg->cmsg_type);
+				break;
+			}
+		} else {
+			struct protoent *p = getprotobynumber(cmsg->cmsg_level);
+
+			printf("%u<%s>, type=%d", cmsg->cmsg_level,
+			    p != NULL ? p->p_name : "unknown", cmsg->cmsg_type);
+		}
+		printf(" }");
+	}
+	printf("\n");
+}
+
 void
 ktrstruct(char *buf, size_t buflen)
 {
@@ -449,6 +528,7 @@ ktrstruct(char *buf, size_t buflen)
 		ktrtfork(&tf);
 	} else if (strcmp(name, "fdset") == 0) {
 		struct fd_set *fds;
+
 		if ((fds = malloc(datalen)) == NULL)
 			err(1, "malloc");
 		memcpy(fds, data, datalen);
@@ -461,6 +541,25 @@ ktrstruct(char *buf, size_t buflen)
 			goto invalid;
 		memcpy(&quota, data, datalen);
 		ktrquota(&quota);
+	} else if (strcmp(name, "msghdr") == 0) {
+		struct msghdr msg;
+
+		if (datalen != sizeof(msg))
+			goto invalid;
+		memcpy(&msg, data, datalen);
+		ktrmsghdr(&msg);
+	} else if (strcmp(name, "iovec") == 0) {
+		if (datalen % sizeof(struct iovec))
+			goto invalid;
+		ktriovec(data, datalen / sizeof(struct iovec));
+	} else if (strcmp(name, "cmsghdr") == 0) {
+		char *cmsg;
+
+		if ((cmsg = malloc(datalen)) == NULL)
+			err(1, "malloc");
+		memcpy(cmsg, data, datalen);
+		ktrcmsghdr(cmsg, datalen);
+		free(cmsg);
 	} else {
 		printf("unknown structure %s\n", name);
 	}