freebsd-skq/lib/libnv/msgio.c
pfg 260ba0bff1 lib: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-26 02:00:33 +00:00

471 lines
9.3 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* 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/param.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
#define PKG_MAX_SIZE (MCLBYTES / CMSG_SPACE(sizeof(int)) - 1)
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);
}
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);
}
static int
fd_package_send(int sock, const int *fds, size_t nfds)
{
struct msghdr msg;
struct cmsghdr *cmsg;
struct iovec iov;
unsigned int i;
int serrno, ret;
uint8_t dummy;
PJDLOG_ASSERT(sock >= 0);
PJDLOG_ASSERT(fds != NULL);
PJDLOG_ASSERT(nfds > 0);
bzero(&msg, sizeof(msg));
/*
* XXX: Look into cred_send function for more details.
*/
dummy = 0;
iov.iov_base = &dummy;
iov.iov_len = sizeof(dummy);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
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);
}
static int
fd_package_recv(int sock, int *fds, size_t nfds)
{
struct msghdr msg;
struct cmsghdr *cmsg;
unsigned int i;
int serrno, ret;
struct iovec iov;
uint8_t dummy;
PJDLOG_ASSERT(sock >= 0);
PJDLOG_ASSERT(nfds > 0);
PJDLOG_ASSERT(fds != NULL);
bzero(&msg, sizeof(msg));
bzero(&iov, sizeof(iov));
/*
* XXX: Look into cred_send function for more details.
*/
iov.iov_base = &dummy;
iov.iov_len = sizeof(dummy);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
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
fd_recv(int sock, int *fds, size_t nfds)
{
unsigned int i, step, j;
int ret, serrno;
if (nfds == 0 || fds == NULL) {
errno = EINVAL;
return (-1);
}
ret = i = step = 0;
while (i < nfds) {
if (PKG_MAX_SIZE < nfds - i)
step = PKG_MAX_SIZE;
else
step = nfds - i;
ret = fd_package_recv(sock, fds + i, step);
if (ret != 0) {
/* Close all received descriptors. */
serrno = errno;
for (j = 0; j < i; j++)
close(fds[j]);
errno = serrno;
break;
}
i += step;
}
return (ret);
}
int
fd_send(int sock, const int *fds, size_t nfds)
{
unsigned int i, step;
int ret;
if (nfds == 0 || fds == NULL) {
errno = EINVAL;
return (-1);
}
ret = i = step = 0;
while (i < nfds) {
if (PKG_MAX_SIZE < nfds - i)
step = PKG_MAX_SIZE;
else
step = nfds - i;
ret = fd_package_send(sock, fds + i, step);
if (ret != 0)
break;
i += step;
}
return (ret);
}
int
buf_send(int sock, void *buf, size_t size)
{
ssize_t done;
unsigned char *ptr;
PJDLOG_ASSERT(sock >= 0);
PJDLOG_ASSERT(size > 0);
PJDLOG_ASSERT(buf != NULL);
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;
PJDLOG_ASSERT(sock >= 0);
PJDLOG_ASSERT(buf != NULL);
ptr = buf;
while (size > 0) {
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;
}
return (0);
}