Bring in libnv library for managing name/value pairs. The following types

are currently supported:

- NV_TYPE_NULL - only name, no data;
- NV_TYPE_BOOL - boolean (true or false);
- NV_TYPE_NUMBER - 64bit unsigned integer;
- NV_TYPE_STRING - C string;
- NV_TYPE_NVLIST - nested nvlist;
- NV_TYPE_DESCRIPTOR - file descriptor;
- NV_TYPE_BINARY - binary data.

For detailed documentation and examples see nv(3) manual page.

Sponsored by:	The FreeBSD Foundation

1 files changed, 407 insertions, 0 deletions

diff --git a/lib/libnv/msgio.c b/lib/libnv/msgio.c
new file mode 100644
index 0000000..a37d1cd
--- /dev/null
+++ b/lib/libnv/msgio.c
@@ -0,0 +1,407 @@
+/*-
+ * Copyright (c) 2013 The FreeBSD Foundation
+ * Copyright (c) 2013 Mariusz Zaborski <oshogbo@FreeBSD.org>
+ * All rights reserved.
+ *
+ * This software was developed by Pawel Jakub Dawidek under sponsorship from
+ * the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifdef HAVE_PJDLOG
+#include <pjdlog.h>
+#endif
+
+#include "common_impl.h"
+#include "msgio.h"
+
+#ifndef	HAVE_PJDLOG
+#include <assert.h>
+#define	PJDLOG_ASSERT(...)		assert(__VA_ARGS__)
+#define	PJDLOG_RASSERT(expr, ...)	assert(expr)
+#define	PJDLOG_ABORT(...)		abort()
+#endif
+
+static int
+msghdr_add_fd(struct cmsghdr *cmsg, int fd)
+{
+
+	PJDLOG_ASSERT(fd >= 0);
+
+	if (!fd_is_valid(fd)) {
+		errno = EBADF;
+		return (-1);
+	}
+
+	cmsg->cmsg_level = SOL_SOCKET;
+	cmsg->cmsg_type = SCM_RIGHTS;
+	cmsg->cmsg_len = CMSG_LEN(sizeof(fd));
+	bcopy(&fd, CMSG_DATA(cmsg), sizeof(fd));
+
+	return (0);
+}
+
+static int
+msghdr_get_fd(struct cmsghdr *cmsg)
+{
+	int fd;
+
+	if (cmsg == NULL || cmsg->cmsg_level != SOL_SOCKET ||
+	    cmsg->cmsg_type != SCM_RIGHTS ||
+	    cmsg->cmsg_len != CMSG_LEN(sizeof(fd))) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	bcopy(CMSG_DATA(cmsg), &fd, sizeof(fd));
+#ifndef MSG_CMSG_CLOEXEC
+	/*
+	 * If the MSG_CMSG_CLOEXEC flag is not available we cannot set the
+	 * close-on-exec flag atomically, but we still want to set it for
+	 * consistency.
+	 */
+	(void) fcntl(fd, F_SETFD, FD_CLOEXEC);
+#endif
+
+	return (fd);
+}
+
+static void
+fd_wait(int fd, bool doread)
+{
+	fd_set fds;
+
+	PJDLOG_ASSERT(fd >= 0);
+
+	FD_ZERO(&fds);
+	FD_SET(fd, &fds);
+	(void)select(fd + 1, doread ? &fds : NULL, doread ? NULL : &fds,
+	    NULL, NULL);
+}
+
+int
+msg_peek(int sock, void *buf, size_t size)
+{
+	ssize_t done;
+
+	PJDLOG_ASSERT(sock >= 0);
+	PJDLOG_ASSERT(size > 0);
+
+	do {
+		fd_wait(sock, true);
+		done = recv(sock, buf, size, MSG_PEEK | MSG_WAITALL);
+		if (done == -1) {
+			if (errno == EAGAIN || errno == EINTR)
+				continue;
+			return (-1);
+		} else if (done == 0) {
+			errno = ENOTCONN;
+			return (-1);
+		}
+	} while (done != (ssize_t)size);
+
+	return (0);
+}
+
+static int
+msg_recv(int sock, struct msghdr *msg)
+{
+	int flags;
+
+	PJDLOG_ASSERT(sock >= 0);
+
+#ifdef MSG_CMSG_CLOEXEC
+	flags = MSG_CMSG_CLOEXEC;
+#else
+	flags = 0;
+#endif
+
+	for (;;) {
+		fd_wait(sock, true);
+		if (recvmsg(sock, msg, flags) == -1) {
+			if (errno == EINTR)
+				continue;
+			return (-1);
+		}
+		break;
+	}
+
+	return (0);
+}
+
+static int
+msg_send(int sock, const struct msghdr *msg)
+{
+
+	PJDLOG_ASSERT(sock >= 0);
+
+	for (;;) {
+		fd_wait(sock, false);
+		if (sendmsg(sock, msg, 0) == -1) {
+			if (errno == EINTR)
+				continue;
+			return (-1);
+		}
+		break;
+	}
+
+	return (0);
+}
+
+int
+cred_send(int sock)
+{
+	unsigned char credbuf[CMSG_SPACE(sizeof(struct cmsgcred))];
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	struct iovec iov;
+	uint8_t dummy;
+
+	bzero(credbuf, sizeof(credbuf));
+	bzero(&msg, sizeof(msg));
+	bzero(&iov, sizeof(iov));
+
+	/*
+	 * XXX: We send one byte along with the control message, because
+	 *      setting msg_iov to NULL only works if this is the first
+	 *      packet send over the socket. Once we send some data we
+	 *      won't be able to send credentials anymore. This is most
+	 *      likely a kernel bug.
+	 */
+	dummy = 0;
+	iov.iov_base = &dummy;
+	iov.iov_len = sizeof(dummy);
+
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_control = credbuf;
+	msg.msg_controllen = sizeof(credbuf);
+
+	cmsg = CMSG_FIRSTHDR(&msg);
+	cmsg->cmsg_len = CMSG_LEN(sizeof(struct cmsgcred));
+	cmsg->cmsg_level = SOL_SOCKET;
+	cmsg->cmsg_type = SCM_CREDS;
+
+	if (msg_send(sock, &msg) == -1)
+		return (-1);
+
+	return (0);
+}
+
+int
+cred_recv(int sock, struct cmsgcred *cred)
+{
+	unsigned char credbuf[CMSG_SPACE(sizeof(struct cmsgcred))];
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	struct iovec iov;
+	uint8_t dummy;
+
+	bzero(credbuf, sizeof(credbuf));
+	bzero(&msg, sizeof(msg));
+	bzero(&iov, sizeof(iov));
+
+	iov.iov_base = &dummy;
+	iov.iov_len = sizeof(dummy);
+
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_control = credbuf;
+	msg.msg_controllen = sizeof(credbuf);
+
+	if (msg_recv(sock, &msg) == -1)
+		return (-1);
+
+	cmsg = CMSG_FIRSTHDR(&msg);
+	if (cmsg == NULL ||
+	    cmsg->cmsg_len != CMSG_LEN(sizeof(struct cmsgcred)) ||
+	    cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_CREDS) {
+		errno = EINVAL;
+		return (-1);
+	}
+	bcopy(CMSG_DATA(cmsg), cred, sizeof(*cred));
+
+	return (0);
+}
+
+int
+fd_send(int sock, const int *fds, size_t nfds)
+{
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	unsigned int i;
+	int serrno, ret;
+
+	if (nfds == 0 || fds == NULL) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	bzero(&msg, sizeof(msg));
+	msg.msg_iov = NULL;
+	msg.msg_iovlen = 0;
+	msg.msg_controllen = nfds * CMSG_SPACE(sizeof(int));
+	msg.msg_control = calloc(1, msg.msg_controllen);
+	if (msg.msg_control == NULL)
+		return (-1);
+
+	ret = -1;
+
+	for (i = 0, cmsg = CMSG_FIRSTHDR(&msg); i < nfds && cmsg != NULL;
+	    i++, cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+		if (msghdr_add_fd(cmsg, fds[i]) == -1)
+			goto end;
+	}
+
+	if (msg_send(sock, &msg) == -1)
+		goto end;
+
+	ret = 0;
+end:
+	serrno = errno;
+	free(msg.msg_control);
+	errno = serrno;
+	return (ret);
+}
+
+int
+fd_recv(int sock, int *fds, size_t nfds)
+{
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	unsigned int i;
+	int serrno, ret;
+
+	if (nfds == 0 || fds == NULL) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	bzero(&msg, sizeof(msg));
+	msg.msg_iov = NULL;
+	msg.msg_iovlen = 0;
+	msg.msg_controllen = nfds * CMSG_SPACE(sizeof(int));
+	msg.msg_control = calloc(1, msg.msg_controllen);
+	if (msg.msg_control == NULL)
+		return (-1);
+
+	ret = -1;
+
+	if (msg_recv(sock, &msg) == -1)
+		goto end;
+
+	for (i = 0, cmsg = CMSG_FIRSTHDR(&msg); i < nfds && cmsg != NULL;
+	    i++, cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+		fds[i] = msghdr_get_fd(cmsg);
+		if (fds[i] < 0)
+			break;
+	}
+
+	if (cmsg != NULL || i < nfds) {
+		int fd;
+
+		/*
+		 * We need to close all received descriptors, even if we have
+		 * different control message (eg. SCM_CREDS) in between.
+		 */
+		for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
+		    cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+			fd = msghdr_get_fd(cmsg);
+			if (fd >= 0)
+				close(fd);
+		}
+		errno = EINVAL;
+		goto end;
+	}
+
+	ret = 0;
+end:
+	serrno = errno;
+	free(msg.msg_control);
+	errno = serrno;
+	return (ret);
+}
+
+int
+buf_send(int sock, void *buf, size_t size)
+{
+	ssize_t done;
+	unsigned char *ptr;
+
+	ptr = buf;
+	do {
+		fd_wait(sock, false);
+		done = send(sock, ptr, size, 0);
+		if (done == -1) {
+			if (errno == EINTR)
+				continue;
+			return (-1);
+		} else if (done == 0) {
+			errno = ENOTCONN;
+			return (-1);
+		}
+		size -= done;
+		ptr += done;
+	} while (size > 0);
+
+	return (0);
+}
+
+int
+buf_recv(int sock, void *buf, size_t size)
+{
+	ssize_t done;
+	unsigned char *ptr;
+
+	ptr = buf;
+	do {
+		fd_wait(sock, true);
+		done = recv(sock, ptr, size, 0);
+		if (done == -1) {
+			if (errno == EINTR)
+				continue;
+			return (-1);
+		} else if (done == 0) {
+			errno = ENOTCONN;
+			return (-1);
+		}
+		size -= done;
+		ptr += done;
+	} while (size > 0);
+
+	return (0);
+}