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bus: split socket related code into bus-socket.[ch], to prepare for kdbus backend

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This commit is contained in:
Lennart Poettering 2013-03-25 03:04:03 +01:00
parent 2fd9ae2e9b
commit a7e3212d89
6 changed files with 759 additions and 643 deletions
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2
Makefile.am
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@ -1661,6 +1661,8 @@ libsystemd_bus_la_SOURCES = \
src/libsystemd-bus/bus-error.h \
src/libsystemd-bus/bus-internal.c \
src/libsystemd-bus/bus-internal.h \
src/libsystemd-bus/bus-socket.c \
src/libsystemd-bus/bus-socket.h \
src/libsystemd-bus/bus-message.c \
src/libsystemd-bus/bus-message.h \
src/libsystemd-bus/bus-signature.c \

2
src/libsystemd-bus/bus-internal.h
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@ -158,3 +158,5 @@ bool member_name_is_valid(const char *p);
#define error_name_is_valid interface_name_is_valid
int bus_ensure_running(sd_bus *bus);
int bus_start_running(sd_bus *bus);
int bus_next_address(sd_bus *bus);

628
src/libsystemd-bus/bus-socket.c Normal file
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@ -0,0 +1,628 @@
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2013 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <endian.h>
#include <assert.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/poll.h>
#include <byteswap.h>
#include "util.h"
#include "macro.h"
#include "missing.h"
#include "strv.h"
#include "sd-bus.h"
#include "bus-socket.h"
#include "bus-internal.h"
#include "bus-message.h"
static void iovec_advance(struct iovec *iov, unsigned *idx, size_t size) {
while (size > 0) {
struct iovec *i = iov + *idx;
if (i->iov_len > size) {
i->iov_base = (uint8_t*) i->iov_base + size;
i->iov_len -= size;
return;
}
size -= i->iov_len;
i->iov_base = NULL;
i->iov_len = 0;
(*idx) ++;
}
}
static int bus_socket_write_auth(sd_bus *b) {
struct msghdr mh;
ssize_t k;
assert(b);
assert(b->state == BUS_AUTHENTICATING);
if (b->auth_index >= ELEMENTSOF(b->auth_iovec))
return 0;
if (b->auth_timeout == 0)
b->auth_timeout = now(CLOCK_MONOTONIC) + BUS_DEFAULT_TIMEOUT;
zero(mh);
mh.msg_iov = b->auth_iovec + b->auth_index;
mh.msg_iovlen = ELEMENTSOF(b->auth_iovec) - b->auth_index;
k = sendmsg(b->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
iovec_advance(b->auth_iovec, &b->auth_index, (size_t) k);
return 1;
}
static int bus_socket_auth_verify(sd_bus *b) {
char *e, *f, *start;
sd_id128_t peer;
unsigned i;
int r;
/* We expect two response lines: "OK" and possibly
* "AGREE_UNIX_FD" */
e = memmem(b->rbuffer, b->rbuffer_size, "\r\n", 2);
if (!e)
return 0;
if (b->negotiate_fds) {
f = memmem(e + 2, b->rbuffer_size - (e - (char*) b->rbuffer) - 2, "\r\n", 2);
if (!f)
return 0;
start = f + 2;
} else {
f = NULL;
start = e + 2;
}
/* Nice! We got all the lines we need. First check the OK
* line */
if (e - (char*) b->rbuffer != 3 + 32)
return -EPERM;
if (memcmp(b->rbuffer, "OK ", 3))
return -EPERM;
for (i = 0; i < 32; i += 2) {
int x, y;
x = unhexchar(((char*) b->rbuffer)[3 + i]);
y = unhexchar(((char*) b->rbuffer)[3 + i + 1]);
if (x < 0 || y < 0)
return -EINVAL;
peer.bytes[i/2] = ((uint8_t) x << 4 | (uint8_t) y);
}
if (!sd_id128_equal(b->peer, SD_ID128_NULL) &&
!sd_id128_equal(b->peer, peer))
return -EPERM;
b->peer = peer;
/* And possibly check the second line, too */
if (f)
b->can_fds =
(f - e == sizeof("\r\nAGREE_UNIX_FD") - 1) &&
memcmp(e + 2, "AGREE_UNIX_FD", sizeof("AGREE_UNIX_FD") - 1) == 0;
b->rbuffer_size -= (start - (char*) b->rbuffer);
memmove(b->rbuffer, start, b->rbuffer_size);
r = bus_start_running(b);
if (r < 0)
return r;
return 1;
}
static int bus_socket_read_auth(sd_bus *b) {
struct msghdr mh;
struct iovec iov;
size_t n;
ssize_t k;
int r;
void *p;
assert(b);
r = bus_socket_auth_verify(b);
if (r != 0)
return r;
n = MAX(3 + 32 + 2 + sizeof("AGREE_UNIX_FD") - 1 + 2, b->rbuffer_size * 2);
if (n > BUS_AUTH_SIZE_MAX)
n = BUS_AUTH_SIZE_MAX;
if (b->rbuffer_size >= n)
return -ENOBUFS;
p = realloc(b->rbuffer, n);
if (!p)
return -ENOMEM;
b->rbuffer = p;
zero(iov);
iov.iov_base = (uint8_t*) b->rbuffer + b->rbuffer_size;
iov.iov_len = n - b->rbuffer_size;
zero(mh);
mh.msg_iov = &iov;
mh.msg_iovlen = 1;
k = recvmsg(b->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
if (k == 0)
return -ECONNRESET;
b->rbuffer_size += k;
r = bus_socket_auth_verify(b);
if (r != 0)
return r;
return 1;
}
static int bus_socket_setup(sd_bus *b) {
int one;
assert(b);
/* Enable SO_PASSCRED + SO_PASSEC. We try this on any socket,
* just in case. This is actually irrelavant for */
one = 1;
setsockopt(b->fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one));
setsockopt(b->fd, SOL_SOCKET, SO_PASSSEC, &one, sizeof(one));
/* Increase the buffers to a MB */
fd_inc_rcvbuf(b->fd, 1024*1024);
fd_inc_sndbuf(b->fd, 1024*1024);
return 0;
}
static int bus_socket_start_auth(sd_bus *b) {
static const char auth_prefix[] = "\0AUTH EXTERNAL ";
static const char auth_suffix_with_unix_fd[] = "\r\nNEGOTIATE_UNIX_FD\r\nBEGIN\r\n";
static const char auth_suffix_without_unix_fd[] = "\r\nBEGIN\r\n";
char text[20 + 1]; /* enough space for a 64bit integer plus NUL */
size_t l;
const char *auth_suffix;
int domain = 0, r;
socklen_t sl;
assert(b);
b->state = BUS_AUTHENTICATING;
sl = sizeof(domain);
r = getsockopt(b->fd, SOL_SOCKET, SO_DOMAIN, &domain, &sl);
if (r < 0)
return -errno;
if (domain != AF_UNIX)
b->negotiate_fds = false;
snprintf(text, sizeof(text), "%llu", (unsigned long long) geteuid());
char_array_0(text);
l = strlen(text);
b->auth_uid = hexmem(text, l);
if (!b->auth_uid)
return -ENOMEM;
auth_suffix = b->negotiate_fds ? auth_suffix_with_unix_fd : auth_suffix_without_unix_fd;
b->auth_iovec[0].iov_base = (void*) auth_prefix;
b->auth_iovec[0].iov_len = sizeof(auth_prefix) -1;
b->auth_iovec[1].iov_base = (void*) b->auth_uid;
b->auth_iovec[1].iov_len = l * 2;
b->auth_iovec[2].iov_base = (void*) auth_suffix;
b->auth_iovec[2].iov_len = strlen(auth_suffix);
b->auth_size = sizeof(auth_prefix) - 1 + l * 2 + sizeof(auth_suffix) - 1;
return bus_socket_write_auth(b);
}
int bus_socket_connect(sd_bus *b) {
int r;
assert(b);
assert(b->fd < 0);
assert(b->sockaddr.sa.sa_family != AF_UNSPEC);
b->fd = socket(b->sockaddr.sa.sa_family, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
if (b->fd < 0)
return -errno;
r = bus_socket_setup(b);
if (r < 0)
return r;
r = connect(b->fd, &b->sockaddr.sa, b->sockaddr_size);
if (r < 0) {
if (errno == EINPROGRESS)
return 1;
return -errno;
}
return bus_socket_start_auth(b);
}
int bus_socket_exec(sd_bus *b) {
int s[2];
pid_t pid;
assert(b);
assert(b->fd < 0);
assert(b->exec_path);
b->fd = socketpair(AF_UNIX, SOCK_STREAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, s);
if (b->fd < 0)
return -errno;
pid = fork();
if (pid < 0) {
close_pipe(s);
return -errno;
}
if (pid == 0) {
/* Child */
close_all_fds(s, 2);
close_nointr_nofail(s[0]);
assert_se(dup3(s[1], STDIN_FILENO, 0) == STDIN_FILENO);
assert_se(dup3(s[1], STDOUT_FILENO, 0) == STDOUT_FILENO);
if (s[1] != STDIN_FILENO && s[1] != STDOUT_FILENO)
close_nointr_nofail(s[1]);
fd_cloexec(STDIN_FILENO, false);
fd_cloexec(STDOUT_FILENO, false);
fd_nonblock(STDIN_FILENO, false);
fd_nonblock(STDOUT_FILENO, false);
if (b->exec_argv)
execvp(b->exec_path, b->exec_argv);
else {
const char *argv[] = { b->exec_path, NULL };
execvp(b->exec_path, (char**) argv);
}
_exit(EXIT_FAILURE);
}
close_nointr_nofail(s[1]);
b->fd = s[0];
return bus_socket_start_auth(b);
}
int bus_socket_take_fd(sd_bus *b) {
int r;
assert(b);
r = bus_socket_setup(b);
if (r < 0)
return r;
return bus_socket_start_auth(b);
}
int bus_socket_write_message(sd_bus *bus, sd_bus_message *m, size_t *idx) {
struct msghdr mh;
struct iovec *iov;
ssize_t k;
size_t n;
unsigned j;
assert(bus);
assert(m);
assert(idx);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
if (*idx >= m->size)
return 0;
zero(mh);
if (m->n_fds > 0) {
struct cmsghdr *control;
control = alloca(CMSG_SPACE(sizeof(int) * m->n_fds));
mh.msg_control = control;
control->cmsg_level = SOL_SOCKET;
control->cmsg_type = SCM_RIGHTS;
mh.msg_controllen = control->cmsg_len = CMSG_LEN(sizeof(int) * m->n_fds);
memcpy(CMSG_DATA(control), m->fds, sizeof(int) * m->n_fds);
}
n = m->n_iovec * sizeof(struct iovec);
iov = alloca(n);
memcpy(iov, m->iovec, n);
j = 0;
iovec_advance(iov, &j, *idx);
mh.msg_iov = iov;
mh.msg_iovlen = m->n_iovec;
k = sendmsg(bus->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
*idx += (size_t) k;
return 1;
}
static int bus_socket_read_message_need(sd_bus *bus, size_t *need) {
uint32_t a, b;
uint8_t e;
uint64_t sum;
assert(bus);
assert(need);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
if (bus->rbuffer_size < sizeof(struct bus_header)) {
*need = sizeof(struct bus_header) + 8;
/* Minimum message size:
*
* Header +
*
* Method Call: +2 string headers
* Signal: +3 string headers
* Method Error: +1 string headers
* +1 uint32 headers
* Method Reply: +1 uint32 headers
*
* A string header is at least 9 bytes
* A uint32 header is at least 8 bytes
*
* Hence the minimum message size of a valid message
* is header + 8 bytes */
return 0;
}
a = ((const uint32_t*) bus->rbuffer)[1];
b = ((const uint32_t*) bus->rbuffer)[3];
e = ((const uint8_t*) bus->rbuffer)[0];
if (e == SD_BUS_LITTLE_ENDIAN) {
a = le32toh(a);
b = le32toh(b);
} else if (e == SD_BUS_BIG_ENDIAN) {
a = be32toh(a);
b = be32toh(b);
} else
return -EBADMSG;
sum = (uint64_t) sizeof(struct bus_header) + (uint64_t) ALIGN_TO(b, 8) + (uint64_t) a;
if (sum >= BUS_MESSAGE_SIZE_MAX)
return -ENOBUFS;
*need = (size_t) sum;
return 0;
}
static int bus_socket_make_message(sd_bus *bus, size_t size, sd_bus_message **m) {
sd_bus_message *t;
void *b;
int r;
assert(bus);
assert(m);
assert(bus->rbuffer_size >= size);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
if (bus->rbuffer_size > size) {
b = memdup((const uint8_t*) bus->rbuffer + size,
bus->rbuffer_size - size);
if (!b)
return -ENOMEM;
} else
b = NULL;
r = bus_message_from_malloc(bus->rbuffer, size,
bus->fds, bus->n_fds,
bus->ucred_valid ? &bus->ucred : NULL,
bus->label[0] ? bus->label : NULL,
&t);
if (r < 0) {
free(b);
return r;
}
bus->rbuffer = b;
bus->rbuffer_size -= size;
bus->fds = NULL;
bus->n_fds = 0;
*m = t;
return 1;
}
int bus_socket_read_message(sd_bus *bus, sd_bus_message **m) {
struct msghdr mh;
struct iovec iov;
ssize_t k;
size_t need;
int r;
void *b;
union {
struct cmsghdr cmsghdr;
uint8_t buf[CMSG_SPACE(sizeof(int) * BUS_FDS_MAX) +
CMSG_SPACE(sizeof(struct ucred)) +
CMSG_SPACE(NAME_MAX)]; /*selinux label */
} control;
struct cmsghdr *cmsg;
assert(bus);
assert(m);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
r = bus_socket_read_message_need(bus, &need);
if (r < 0)
return r;
if (bus->rbuffer_size >= need)
return bus_socket_make_message(bus, need, m);
b = realloc(bus->rbuffer, need);
if (!b)
return -ENOMEM;
bus->rbuffer = b;
zero(iov);
iov.iov_base = (uint8_t*) bus->rbuffer + bus->rbuffer_size;
iov.iov_len = need - bus->rbuffer_size;
zero(mh);
mh.msg_iov = &iov;
mh.msg_iovlen = 1;
mh.msg_control = &control;
mh.msg_controllen = sizeof(control);
k = recvmsg(bus->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC);
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
if (k == 0)
return -ECONNRESET;
bus->rbuffer_size += k;
for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg)) {
if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_RIGHTS) {
int n, *f;
n = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
f = realloc(bus->fds, sizeof(int) + (bus->n_fds + n));
if (!f) {
close_many((int*) CMSG_DATA(cmsg), n);
return -ENOMEM;
}
memcpy(f + bus->n_fds, CMSG_DATA(cmsg), n * sizeof(int));
bus->fds = f;
bus->n_fds += n;
} else if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_CREDENTIALS &&
cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred))) {
memcpy(&bus->ucred, CMSG_DATA(cmsg), sizeof(struct ucred));
bus->ucred_valid = true;
} else if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_SECURITY) {
size_t l;
l = cmsg->cmsg_len - CMSG_LEN(0);
memcpy(&bus->label, CMSG_DATA(cmsg), l);
bus->label[l] = 0;
}
}
r = bus_socket_read_message_need(bus, &need);
if (r < 0)
return r;
if (bus->rbuffer_size >= need)
return bus_socket_make_message(bus, need, m);
return 1;
}
int bus_socket_process_opening(sd_bus *b) {
int error = 0;
socklen_t slen = sizeof(error);
struct pollfd p;
int r;
assert(b);
assert(b->state == BUS_OPENING);
zero(p);
p.fd = b->fd;
p.events = POLLOUT;
r = poll(&p, 1, 0);
if (r < 0)
return -errno;
if (!(p.revents & (POLLOUT|POLLERR|POLLHUP)))
return 0;
r = getsockopt(b->fd, SOL_SOCKET, SO_ERROR, &error, &slen);
if (r < 0)
b->last_connect_error = errno;
else if (error != 0)
b->last_connect_error = error;
else if (p.revents & (POLLERR|POLLHUP))
b->last_connect_error = ECONNREFUSED;
else
return bus_socket_start_auth(b);
return bus_next_address(b);
}
int bus_socket_process_authenticating(sd_bus *b) {
int r;
assert(b);
assert(b->state == BUS_AUTHENTICATING);
if (now(CLOCK_MONOTONIC) >= b->auth_timeout)
return -ETIMEDOUT;
r = bus_socket_write_auth(b);
if (r != 0)
return r;
return bus_socket_read_auth(b);
}

34
src/libsystemd-bus/bus-socket.h Normal file
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@ -0,0 +1,34 @@
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
#pragma once
/***
This file is part of systemd.
Copyright 2013 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include "sd-bus.h"
int bus_socket_connect(sd_bus *b);
int bus_socket_exec(sd_bus *b);
int bus_socket_take_fd(sd_bus *b);
int bus_socket_write_message(sd_bus *bus, sd_bus_message *m, size_t *idx);
int bus_socket_read_message(sd_bus *bus, sd_bus_message **m);
int bus_socket_process_opening(sd_bus *b);
int bus_socket_process_authenticating(sd_bus *b);

734
src/libsystemd-bus/sd-bus.c
View File

@ -29,13 +29,13 @@
#include "util.h"
#include "macro.h"
#include "missing.h"
#include "strv.h"
#include "sd-bus.h"
#include "bus-internal.h"
#include "bus-message.h"
#include "bus-type.h"
#include "bus-socket.h"
static int bus_poll(sd_bus *bus, bool need_more, uint64_t timeout_usec);
@ -250,7 +250,7 @@ static int bus_send_hello(sd_bus *bus) {
return r;
}
static int bus_start_running(sd_bus *bus) {
int bus_start_running(sd_bus *bus) {
assert(bus);
if (bus->send_hello) {
@ -648,310 +648,7 @@ static int bus_parse_next_address(sd_bus *b) {
return 1;
}
static void iovec_advance(struct iovec *iov, unsigned *idx, size_t size) {
while (size > 0) {
struct iovec *i = iov + *idx;
if (i->iov_len > size) {
i->iov_base = (uint8_t*) i->iov_base + size;
i->iov_len -= size;
return;
}
size -= i->iov_len;
i->iov_base = NULL;
i->iov_len = 0;
(*idx) ++;
}
}
static int bus_write_auth(sd_bus *b) {
struct msghdr mh;
ssize_t k;
assert(b);
assert(b->state == BUS_AUTHENTICATING);
if (b->auth_index >= ELEMENTSOF(b->auth_iovec))
return 0;
if (b->auth_timeout == 0)
b->auth_timeout = now(CLOCK_MONOTONIC) + BUS_DEFAULT_TIMEOUT;
zero(mh);
mh.msg_iov = b->auth_iovec + b->auth_index;
mh.msg_iovlen = ELEMENTSOF(b->auth_iovec) - b->auth_index;
k = sendmsg(b->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
iovec_advance(b->auth_iovec, &b->auth_index, (size_t) k);
return 1;
}
static int bus_auth_verify(sd_bus *b) {
char *e, *f, *start;
sd_id128_t peer;
unsigned i;
int r;
/* We expect two response lines: "OK" and possibly
* "AGREE_UNIX_FD" */
e = memmem(b->rbuffer, b->rbuffer_size, "\r\n", 2);
if (!e)
return 0;
if (b->negotiate_fds) {
f = memmem(e + 2, b->rbuffer_size - (e - (char*) b->rbuffer) - 2, "\r\n", 2);
if (!f)
return 0;
start = f + 2;
} else {
f = NULL;
start = e + 2;
}
/* Nice! We got all the lines we need. First check the OK
* line */
if (e - (char*) b->rbuffer != 3 + 32)
return -EPERM;
if (memcmp(b->rbuffer, "OK ", 3))
return -EPERM;
for (i = 0; i < 32; i += 2) {
int x, y;
x = unhexchar(((char*) b->rbuffer)[3 + i]);
y = unhexchar(((char*) b->rbuffer)[3 + i + 1]);
if (x < 0 || y < 0)
return -EINVAL;
peer.bytes[i/2] = ((uint8_t) x << 4 | (uint8_t) y);
}
if (!sd_id128_equal(b->peer, SD_ID128_NULL) &&
!sd_id128_equal(b->peer, peer))
return -EPERM;
b->peer = peer;
/* And possibly check the second line, too */
if (f)
b->can_fds =
(f - e == sizeof("\r\nAGREE_UNIX_FD") - 1) &&
memcmp(e + 2, "AGREE_UNIX_FD", sizeof("AGREE_UNIX_FD") - 1) == 0;
b->rbuffer_size -= (start - (char*) b->rbuffer);
memmove(b->rbuffer, start, b->rbuffer_size);
r = bus_start_running(b);
if (r < 0)
return r;
return 1;
}
static int bus_read_auth(sd_bus *b) {
struct msghdr mh;
struct iovec iov;
size_t n;
ssize_t k;
int r;
void *p;
assert(b);
r = bus_auth_verify(b);
if (r != 0)
return r;
n = MAX(3 + 32 + 2 + sizeof("AGREE_UNIX_FD") - 1 + 2, b->rbuffer_size * 2);
if (n > BUS_AUTH_SIZE_MAX)
n = BUS_AUTH_SIZE_MAX;
if (b->rbuffer_size >= n)
return -ENOBUFS;
p = realloc(b->rbuffer, n);
if (!p)
return -ENOMEM;
b->rbuffer = p;
zero(iov);
iov.iov_base = (uint8_t*) b->rbuffer + b->rbuffer_size;
iov.iov_len = n - b->rbuffer_size;
zero(mh);
mh.msg_iov = &iov;
mh.msg_iovlen = 1;
k = recvmsg(b->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
if (k == 0)
return -ECONNRESET;
b->rbuffer_size += k;
r = bus_auth_verify(b);
if (r != 0)
return r;
return 1;
}
static int bus_setup_fd(sd_bus *b) {
int one;
assert(b);
/* Enable SO_PASSCRED + SO_PASSEC. We try this on any socket,
* just in case. This is actually irrelavant for */
one = 1;
setsockopt(b->fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one));
setsockopt(b->fd, SOL_SOCKET, SO_PASSSEC, &one, sizeof(one));
/* Increase the buffers to a MB */
fd_inc_rcvbuf(b->fd, 1024*1024);
fd_inc_sndbuf(b->fd, 1024*1024);
return 0;
}
static int bus_start_auth(sd_bus *b) {
static const char auth_prefix[] = "\0AUTH EXTERNAL ";
static const char auth_suffix_with_unix_fd[] = "\r\nNEGOTIATE_UNIX_FD\r\nBEGIN\r\n";
static const char auth_suffix_without_unix_fd[] = "\r\nBEGIN\r\n";
char text[20 + 1]; /* enough space for a 64bit integer plus NUL */
size_t l;
const char *auth_suffix;
int domain = 0, r;
socklen_t sl;
assert(b);
b->state = BUS_AUTHENTICATING;
sl = sizeof(domain);
r = getsockopt(b->fd, SOL_SOCKET, SO_DOMAIN, &domain, &sl);
if (r < 0)
return -errno;
if (domain != AF_UNIX)
b->negotiate_fds = false;
snprintf(text, sizeof(text), "%llu", (unsigned long long) geteuid());
char_array_0(text);
l = strlen(text);
b->auth_uid = hexmem(text, l);
if (!b->auth_uid)
return -ENOMEM;
auth_suffix = b->negotiate_fds ? auth_suffix_with_unix_fd : auth_suffix_without_unix_fd;
b->auth_iovec[0].iov_base = (void*) auth_prefix;
b->auth_iovec[0].iov_len = sizeof(auth_prefix) -1;
b->auth_iovec[1].iov_base = (void*) b->auth_uid;
b->auth_iovec[1].iov_len = l * 2;
b->auth_iovec[2].iov_base = (void*) auth_suffix;
b->auth_iovec[2].iov_len = strlen(auth_suffix);
b->auth_size = sizeof(auth_prefix) - 1 + l * 2 + sizeof(auth_suffix) - 1;
return bus_write_auth(b);
}
static int bus_connect(sd_bus *b) {
int r;
assert(b);
assert(b->fd < 0);
assert(b->sockaddr.sa.sa_family != AF_UNSPEC);
b->fd = socket(b->sockaddr.sa.sa_family, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
if (b->fd < 0)
return -errno;
r = bus_setup_fd(b);
if (r < 0)
return r;
r = connect(b->fd, &b->sockaddr.sa, b->sockaddr_size);
if (r < 0) {
if (errno == EINPROGRESS)
return 1;
return -errno;
}
return bus_start_auth(b);
}
static int bus_exec(sd_bus *b) {
int s[2];
pid_t pid;
assert(b);
assert(b->fd < 0);
assert(b->exec_path);
b->fd = socketpair(AF_UNIX, SOCK_STREAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, s);
if (b->fd < 0)
return -errno;
pid = fork();
if (pid < 0) {
close_pipe(s);
return -errno;
}
if (pid == 0) {
/* Child */
close_all_fds(s, 2);
close_nointr_nofail(s[0]);
assert_se(dup3(s[1], STDIN_FILENO, 0) == STDIN_FILENO);
assert_se(dup3(s[1], STDOUT_FILENO, 0) == STDOUT_FILENO);
if (s[1] != STDIN_FILENO && s[1] != STDOUT_FILENO)
close_nointr_nofail(s[1]);
fd_cloexec(STDIN_FILENO, false);
fd_cloexec(STDOUT_FILENO, false);
fd_nonblock(STDIN_FILENO, false);
fd_nonblock(STDOUT_FILENO, false);
if (b->exec_argv)
execvp(b->exec_path, b->exec_argv);
else {
const char *argv[] = { b->exec_path, NULL };
execvp(b->exec_path, (char**) argv);
}
_exit(EXIT_FAILURE);
}
close_nointr_nofail(s[1]);
b->fd = s[0];
return bus_start_auth(b);
}
static int bus_start_connect(sd_bus *b) {
static int bus_start_address(sd_bus *b) {
int r;
assert(b);
@ -963,7 +660,8 @@ static int bus_start_connect(sd_bus *b) {
}
if (b->sockaddr.sa.sa_family != AF_UNSPEC) {
r = bus_connect(b);
r = bus_socket_connect(b);
if (r >= 0)
return r;
@ -971,7 +669,7 @@ static int bus_start_connect(sd_bus *b) {
} else if (b->exec_path) {
r = bus_exec(b);
r = bus_socket_exec(b);
if (r >= 0)
return r;
@ -986,6 +684,13 @@ static int bus_start_connect(sd_bus *b) {
}
}
int bus_next_address(sd_bus *b) {
assert(b);
bus_reset_parsed_address(b);
return bus_start_address(b);
}
static int bus_start_fd(sd_bus *b) {
int r;
@ -999,11 +704,7 @@ static int bus_start_fd(sd_bus *b) {
if (r < 0)
return r;
r = bus_setup_fd(b);
if (r < 0)
return r;
return bus_start_auth(b);
return bus_socket_take_fd(b);
}
int sd_bus_start(sd_bus *bus) {
@ -1019,7 +720,7 @@ int sd_bus_start(sd_bus *bus) {
if (bus->fd >= 0)
r = bus_start_fd(bus);
else if (bus->address)
r = bus_start_connect(bus);
r = bus_start_address(bus);
else
return -EINVAL;
@ -1206,234 +907,6 @@ static int bus_seal_message(sd_bus *b, sd_bus_message *m) {
return bus_message_seal(m, ++b->serial);
}
static int message_write(sd_bus *bus, sd_bus_message *m, size_t *idx) {
struct msghdr mh;
struct iovec *iov;
ssize_t k;
size_t n;
unsigned j;
assert(bus);
assert(m);
assert(idx);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
if (*idx >= m->size)
return 0;
zero(mh);
if (m->n_fds > 0) {
struct cmsghdr *control;
control = alloca(CMSG_SPACE(sizeof(int) * m->n_fds));
mh.msg_control = control;
control->cmsg_level = SOL_SOCKET;
control->cmsg_type = SCM_RIGHTS;
mh.msg_controllen = control->cmsg_len = CMSG_LEN(sizeof(int) * m->n_fds);
memcpy(CMSG_DATA(control), m->fds, sizeof(int) * m->n_fds);
}
n = m->n_iovec * sizeof(struct iovec);
iov = alloca(n);
memcpy(iov, m->iovec, n);
j = 0;
iovec_advance(iov, &j, *idx);
mh.msg_iov = iov;
mh.msg_iovlen = m->n_iovec;
k = sendmsg(bus->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
*idx += (size_t) k;
return 1;
}
static int message_read_need(sd_bus *bus, size_t *need) {
uint32_t a, b;
uint8_t e;
uint64_t sum;
assert(bus);
assert(need);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
if (bus->rbuffer_size < sizeof(struct bus_header)) {
*need = sizeof(struct bus_header) + 8;
/* Minimum message size:
*
* Header +
*
* Method Call: +2 string headers
* Signal: +3 string headers
* Method Error: +1 string headers
* +1 uint32 headers
* Method Reply: +1 uint32 headers
*
* A string header is at least 9 bytes
* A uint32 header is at least 8 bytes
*
* Hence the minimum message size of a valid message
* is header + 8 bytes */
return 0;
}
a = ((const uint32_t*) bus->rbuffer)[1];
b = ((const uint32_t*) bus->rbuffer)[3];
e = ((const uint8_t*) bus->rbuffer)[0];
if (e == SD_BUS_LITTLE_ENDIAN) {
a = le32toh(a);
b = le32toh(b);
} else if (e == SD_BUS_BIG_ENDIAN) {
a = be32toh(a);
b = be32toh(b);
} else
return -EBADMSG;
sum = (uint64_t) sizeof(struct bus_header) + (uint64_t) ALIGN_TO(b, 8) + (uint64_t) a;
if (sum >= BUS_MESSAGE_SIZE_MAX)
return -ENOBUFS;
*need = (size_t) sum;
return 0;
}
static int message_make(sd_bus *bus, size_t size, sd_bus_message **m) {
sd_bus_message *t;
void *b;
int r;
assert(bus);
assert(m);
assert(bus->rbuffer_size >= size);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
if (bus->rbuffer_size > size) {
b = memdup((const uint8_t*) bus->rbuffer + size,
bus->rbuffer_size - size);
if (!b)
return -ENOMEM;
} else
b = NULL;
r = bus_message_from_malloc(bus->rbuffer, size,
bus->fds, bus->n_fds,
bus->ucred_valid ? &bus->ucred : NULL,
bus->label[0] ? bus->label : NULL,
&t);
if (r < 0) {
free(b);
return r;
}
bus->rbuffer = b;
bus->rbuffer_size -= size;
bus->fds = NULL;
bus->n_fds = 0;
*m = t;
return 1;
}
static int message_read(sd_bus *bus, sd_bus_message **m) {
struct msghdr mh;
struct iovec iov;
ssize_t k;
size_t need;
int r;
void *b;
union {
struct cmsghdr cmsghdr;
uint8_t buf[CMSG_SPACE(sizeof(int) * BUS_FDS_MAX) +
CMSG_SPACE(sizeof(struct ucred)) +
CMSG_SPACE(NAME_MAX)]; /*selinux label */
} control;
struct cmsghdr *cmsg;
assert(bus);
assert(m);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
r = message_read_need(bus, &need);
if (r < 0)
return r;
if (bus->rbuffer_size >= need)
return message_make(bus, need, m);
b = realloc(bus->rbuffer, need);
if (!b)
return -ENOMEM;
bus->rbuffer = b;
zero(iov);
iov.iov_base = (uint8_t*) bus->rbuffer + bus->rbuffer_size;
iov.iov_len = need - bus->rbuffer_size;
zero(mh);
mh.msg_iov = &iov;
mh.msg_iovlen = 1;
mh.msg_control = &control;
mh.msg_controllen = sizeof(control);
k = recvmsg(bus->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC);
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
if (k == 0)
return -ECONNRESET;
bus->rbuffer_size += k;
for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg)) {
if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_RIGHTS) {
int n, *f;
n = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
f = realloc(bus->fds, sizeof(int) + (bus->n_fds + n));
if (!f) {
close_many((int*) CMSG_DATA(cmsg), n);
return -ENOMEM;
}
memcpy(f + bus->n_fds, CMSG_DATA(cmsg), n * sizeof(int));
bus->fds = f;
bus->n_fds += n;
} else if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_CREDENTIALS &&
cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred))) {
memcpy(&bus->ucred, CMSG_DATA(cmsg), sizeof(struct ucred));
bus->ucred_valid = true;
} else if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_SECURITY) {
size_t l;
l = cmsg->cmsg_len - CMSG_LEN(0);
memcpy(&bus->label, CMSG_DATA(cmsg), l);
bus->label[l] = 0;
}
}
r = message_read_need(bus, &need);
if (r < 0)
return r;
if (bus->rbuffer_size >= need)
return message_make(bus, need, m);
return 1;
}
static int dispatch_wqueue(sd_bus *bus) {
int r, ret = 0;
@ -1445,7 +918,7 @@ static int dispatch_wqueue(sd_bus *bus) {
while (bus->wqueue_size > 0) {
r = message_write(bus, bus->wqueue[0], &bus->windex);
r = bus_socket_write_message(bus, bus->wqueue[0], &bus->windex);
if (r < 0) {
sd_bus_close(bus);
return r;
@ -1497,7 +970,7 @@ static int dispatch_rqueue(sd_bus *bus, sd_bus_message **m) {
/* Try to read a new message */
do {
r = message_read(bus, &z);
r = bus_socket_read_message(bus, &z);
if (r < 0) {
sd_bus_close(bus);
return r;
@ -1549,7 +1022,7 @@ int sd_bus_send(sd_bus *bus, sd_bus_message *m, uint64_t *serial) {
if ((bus->state == BUS_RUNNING || bus->state == BUS_HELLO) && bus->wqueue_size <= 0) {
size_t idx = 0;
r = message_write(bus, m, &idx);
r = bus_socket_write_message(bus, m, &idx);
if (r < 0) {
sd_bus_close(bus);
return r;
@ -1791,7 +1264,7 @@ int sd_bus_send_with_reply_and_block(
room = true;
}
r = message_read(bus, &incoming);
r = bus_socket_read_message(bus, &incoming);
if (r < 0)
return r;
if (incoming) {
@ -2119,6 +1592,61 @@ static int process_message(sd_bus *bus, sd_bus_message *m) {
return process_object(bus, m);
}
static int process_running(sd_bus *bus, sd_bus_message **ret) {
_cleanup_bus_message_unref_ sd_bus_message *m = NULL;
int r;
assert(bus);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
r = process_timeout(bus);
if (r != 0)
goto null_message;
r = dispatch_wqueue(bus);
if (r != 0)
goto null_message;
r = dispatch_rqueue(bus, &m);
if (r < 0)
return r;
if (!m)
goto null_message;
r = process_message(bus, m);
if (r != 0)
goto null_message;
if (ret) {
*ret = m;
m = NULL;
return 1;
}
if (m->header->type == SD_BUS_MESSAGE_TYPE_METHOD_CALL) {
_cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_INIT;
sd_bus_error_set(&error, "org.freedesktop.DBus.Error.UnknownObject", "Unknown object '%s'.", m->path);
r = sd_bus_message_new_method_error(bus, m, &error, &reply);
if (r < 0)
return r;
r = sd_bus_send(bus, reply, NULL);
if (r < 0)
return r;
}
return 1;
null_message:
if (r >= 0 && ret)
*ret = NULL;
return r;
}
int sd_bus_process(sd_bus *bus, sd_bus_message **ret) {
int r;
@ -2129,116 +1657,38 @@ int sd_bus_process(sd_bus *bus, sd_bus_message **ret) {
if (!bus)
return -EINVAL;
if (bus->state == BUS_UNSET)
return -ENOTCONN;
if (bus->fd < 0)
return -ENOTCONN;
if (bus->state == BUS_OPENING) {
struct pollfd p;
switch (bus->state) {
zero(p);
p.fd = bus->fd;
p.events = POLLOUT;
case BUS_UNSET:
return -ENOTCONN;
r = poll(&p, 1, 0);
if (r < 0)
return -errno;
if (p.revents & (POLLOUT|POLLERR|POLLHUP)) {
int error = 0;
socklen_t slen = sizeof(error);
r = getsockopt(bus->fd, SOL_SOCKET, SO_ERROR, &error, &slen);
if (r < 0)
bus->last_connect_error = errno;
else if (error != 0)
bus->last_connect_error = error;
else if (p.revents & (POLLERR|POLLHUP))
bus->last_connect_error = ECONNREFUSED;
else {
r = bus_start_auth(bus);
goto null_message;
}
/* Try next address */
bus_reset_parsed_address(bus);
r = bus_start_connect(bus);
goto null_message;
}
r = 0;
goto null_message;
} else if (bus->state == BUS_AUTHENTICATING) {
if (now(CLOCK_MONOTONIC) >= bus->auth_timeout)
return -ETIMEDOUT;
r = bus_write_auth(bus);
if (r != 0)
goto null_message;
r = bus_read_auth(bus);
goto null_message;
} else if (bus->state == BUS_RUNNING || bus->state == BUS_HELLO) {
_cleanup_bus_message_unref_ sd_bus_message *m = NULL;
int k;
r = process_timeout(bus);
if (r != 0)
goto null_message;
r = dispatch_wqueue(bus);
if (r != 0)
goto null_message;
k = r;
r = dispatch_rqueue(bus, &m);
case BUS_OPENING:
r = bus_socket_process_opening(bus);
if (r < 0)
return r;
if (!m) {
if (r == 0)
r = k;
goto null_message;
}
if (ret)
*ret = NULL;
return r;
r = process_message(bus, m);
if (r != 0)
goto null_message;
case BUS_AUTHENTICATING:
if (ret) {
*ret = m;
m = NULL;
return 1;
}
r = bus_socket_process_authenticating(bus);
if (r < 0)
return r;
if (ret)
*ret = NULL;
return r;
if (m->header->type == SD_BUS_MESSAGE_TYPE_METHOD_CALL) {
_cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_INIT;
case BUS_RUNNING:
case BUS_HELLO:
sd_bus_error_set(&error, "org.freedesktop.DBus.Error.UnknownObject", "Unknown object '%s'.", m->path);
r = sd_bus_message_new_method_error(bus, m, &error, &reply);
if (r < 0)
return r;
r = sd_bus_send(bus, reply, NULL);
if (r < 0)
return r;
}
return 1;
return process_running(bus, ret);
}
assert_not_reached("Unknown state");
null_message:
if (r >= 0 && ret)
*ret = NULL;
return r;
}
static int bus_poll(sd_bus *bus, bool need_more, uint64_t timeout_usec) {

2
src/libsystemd-bus/sd-bus.h
View File

@ -25,12 +25,12 @@
#include <inttypes.h>
#include <sys/types.h>
#include <sd-id128.h>
#include "sd-bus-protocol.h"
/* TODO:
* - implicitly add stub introspection calls
* - server side
* - split out actual sending logic into backend-socket.c
*
* Later:
* - add page donation logic