/*-*- 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 .
***/
#include
#include
#include
#include
#include "sd-daemon.h"
#include "util.h"
#include "macro.h"
#include "missing.h"
#include "utf8.h"
#include "formats-util.h"
#include "signal-util.h"
#include "sd-bus.h"
#include "bus-socket.h"
#include "bus-internal.h"
#include "bus-message.h"
#define SNDBUF_SIZE (8*1024*1024)
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 append_iovec(sd_bus_message *m, const void *p, size_t sz) {
assert(m);
assert(p);
assert(sz > 0);
m->iovec[m->n_iovec].iov_base = (void*) p;
m->iovec[m->n_iovec].iov_len = sz;
m->n_iovec++;
return 0;
}
static int bus_message_setup_iovec(sd_bus_message *m) {
struct bus_body_part *part;
unsigned n, i;
int r;
assert(m);
assert(m->sealed);
if (m->n_iovec > 0)
return 0;
assert(!m->iovec);
n = 1 + m->n_body_parts;
if (n < ELEMENTSOF(m->iovec_fixed))
m->iovec = m->iovec_fixed;
else {
m->iovec = new(struct iovec, n);
if (!m->iovec) {
r = -ENOMEM;
goto fail;
}
}
r = append_iovec(m, m->header, BUS_MESSAGE_BODY_BEGIN(m));
if (r < 0)
goto fail;
MESSAGE_FOREACH_PART(part, i, m) {
r = bus_body_part_map(part);
if (r < 0)
goto fail;
r = append_iovec(m, part->data, part->size);
if (r < 0)
goto fail;
}
assert(n == m->n_iovec);
return 0;
fail:
m->poisoned = true;
return r;
}
bool bus_socket_auth_needs_write(sd_bus *b) {
unsigned i;
if (b->auth_index >= ELEMENTSOF(b->auth_iovec))
return false;
for (i = b->auth_index; i < ELEMENTSOF(b->auth_iovec); i++) {
struct iovec *j = b->auth_iovec + i;
if (j->iov_len > 0)
return true;
}
return false;
}
static int bus_socket_write_auth(sd_bus *b) {
ssize_t k;
assert(b);
assert(b->state == BUS_AUTHENTICATING);
if (!bus_socket_auth_needs_write(b))
return 0;
if (b->prefer_writev)
k = writev(b->output_fd, b->auth_iovec + b->auth_index, ELEMENTSOF(b->auth_iovec) - b->auth_index);
else {
struct msghdr mh;
zero(mh);
mh.msg_iov = b->auth_iovec + b->auth_index;
mh.msg_iovlen = ELEMENTSOF(b->auth_iovec) - b->auth_index;
k = sendmsg(b->output_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
if (k < 0 && errno == ENOTSOCK) {
b->prefer_writev = true;
k = writev(b->output_fd, b->auth_iovec + b->auth_index, ELEMENTSOF(b->auth_iovec) - b->auth_index);
}
}
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_client(sd_bus *b) {
char *e, *f, *start;
sd_id128_t peer;
unsigned i;
int r;
assert(b);
/* We expect two response lines: "OK" and possibly
* "AGREE_UNIX_FD" */
e = memmem_safe(b->rbuffer, b->rbuffer_size, "\r\n", 2);
if (!e)
return 0;
if (b->hello_flags & KDBUS_HELLO_ACCEPT_FD) {
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;
b->auth = b->anonymous_auth ? BUS_AUTH_ANONYMOUS : BUS_AUTH_EXTERNAL;
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->server_id, SD_ID128_NULL) &&
!sd_id128_equal(b->server_id, peer))
return -EPERM;
b->server_id = peer;
/* And possibly check the second line, too */
if (f)
b->can_fds =
(f - e == strlen("\r\nAGREE_UNIX_FD")) &&
memcmp(e + 2, "AGREE_UNIX_FD", strlen("AGREE_UNIX_FD")) == 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 bool line_equals(const char *s, size_t m, const char *line) {
size_t l;
l = strlen(line);
if (l != m)
return false;
return memcmp(s, line, l) == 0;
}
static bool line_begins(const char *s, size_t m, const char *word) {
size_t l;
l = strlen(word);
if (m < l)
return false;
if (memcmp(s, word, l) != 0)
return false;
return m == l || (m > l && s[l] == ' ');
}
static int verify_anonymous_token(sd_bus *b, const char *p, size_t l) {
_cleanup_free_ char *token = NULL;
if (!b->anonymous_auth)
return 0;
if (l <= 0)
return 1;
assert(p[0] == ' ');
p++; l--;
if (l % 2 != 0)
return 0;
token = unhexmem(p, l);
if (!token)
return -ENOMEM;
if (memchr(token, 0, l/2))
return 0;
return !!utf8_is_valid(token);
}
static int verify_external_token(sd_bus *b, const char *p, size_t l) {
_cleanup_free_ char *token = NULL;
uid_t u;
int r;
/* We don't do any real authentication here. Instead, we if
* the owner of this bus wanted authentication he should have
* checked SO_PEERCRED before even creating the bus object. */
if (!b->anonymous_auth && !b->ucred_valid)
return 0;
if (l <= 0)
return 1;
assert(p[0] == ' ');
p++; l--;
if (l % 2 != 0)
return 0;
token = unhexmem(p, l);
if (!token)
return -ENOMEM;
if (memchr(token, 0, l/2))
return 0;
r = parse_uid(token, &u);
if (r < 0)
return 0;
/* We ignore the passed value if anonymous authentication is
* on anyway. */
if (!b->anonymous_auth && u != b->ucred.uid)
return 0;
return 1;
}
static int bus_socket_auth_write(sd_bus *b, const char *t) {
char *p;
size_t l;
assert(b);
assert(t);
/* We only make use of the first iovec */
assert(b->auth_index == 0 || b->auth_index == 1);
l = strlen(t);
p = malloc(b->auth_iovec[0].iov_len + l);
if (!p)
return -ENOMEM;
memcpy(p, b->auth_iovec[0].iov_base, b->auth_iovec[0].iov_len);
memcpy(p + b->auth_iovec[0].iov_len, t, l);
b->auth_iovec[0].iov_base = p;
b->auth_iovec[0].iov_len += l;
free(b->auth_buffer);
b->auth_buffer = p;
b->auth_index = 0;
return 0;
}
static int bus_socket_auth_write_ok(sd_bus *b) {
char t[3 + 32 + 2 + 1];
assert(b);
xsprintf(t, "OK " SD_ID128_FORMAT_STR "\r\n", SD_ID128_FORMAT_VAL(b->server_id));
return bus_socket_auth_write(b, t);
}
static int bus_socket_auth_verify_server(sd_bus *b) {
char *e;
const char *line;
size_t l;
bool processed = false;
int r;
assert(b);
if (b->rbuffer_size < 1)
return 0;
/* First char must be a NUL byte */
if (*(char*) b->rbuffer != 0)
return -EIO;
if (b->rbuffer_size < 3)
return 0;
/* Begin with the first line */
if (b->auth_rbegin <= 0)
b->auth_rbegin = 1;
for (;;) {
/* Check if line is complete */
line = (char*) b->rbuffer + b->auth_rbegin;
e = memmem(line, b->rbuffer_size - b->auth_rbegin, "\r\n", 2);
if (!e)
return processed;
l = e - line;
if (line_begins(line, l, "AUTH ANONYMOUS")) {
r = verify_anonymous_token(b, line + 14, l - 14);
if (r < 0)
return r;
if (r == 0)
r = bus_socket_auth_write(b, "REJECTED\r\n");
else {
b->auth = BUS_AUTH_ANONYMOUS;
r = bus_socket_auth_write_ok(b);
}
} else if (line_begins(line, l, "AUTH EXTERNAL")) {
r = verify_external_token(b, line + 13, l - 13);
if (r < 0)
return r;
if (r == 0)
r = bus_socket_auth_write(b, "REJECTED\r\n");
else {
b->auth = BUS_AUTH_EXTERNAL;
r = bus_socket_auth_write_ok(b);
}
} else if (line_begins(line, l, "AUTH"))
r = bus_socket_auth_write(b, "REJECTED EXTERNAL ANONYMOUS\r\n");
else if (line_equals(line, l, "CANCEL") ||
line_begins(line, l, "ERROR")) {
b->auth = _BUS_AUTH_INVALID;
r = bus_socket_auth_write(b, "REJECTED\r\n");
} else if (line_equals(line, l, "BEGIN")) {
if (b->auth == _BUS_AUTH_INVALID)
r = bus_socket_auth_write(b, "ERROR\r\n");
else {
/* We can't leave from the auth phase
* before we haven't written
* everything queued, so let's check
* that */
if (bus_socket_auth_needs_write(b))
return 1;
b->rbuffer_size -= (e + 2 - (char*) b->rbuffer);
memmove(b->rbuffer, e + 2, b->rbuffer_size);
return bus_start_running(b);
}
} else if (line_begins(line, l, "DATA")) {
if (b->auth == _BUS_AUTH_INVALID)
r = bus_socket_auth_write(b, "ERROR\r\n");
else {
if (b->auth == BUS_AUTH_ANONYMOUS)
r = verify_anonymous_token(b, line + 4, l - 4);
else
r = verify_external_token(b, line + 4, l - 4);
if (r < 0)
return r;
if (r == 0) {
b->auth = _BUS_AUTH_INVALID;
r = bus_socket_auth_write(b, "REJECTED\r\n");
} else
r = bus_socket_auth_write_ok(b);
}
} else if (line_equals(line, l, "NEGOTIATE_UNIX_FD")) {
if (b->auth == _BUS_AUTH_INVALID || !(b->hello_flags & KDBUS_HELLO_ACCEPT_FD))
r = bus_socket_auth_write(b, "ERROR\r\n");
else {
b->can_fds = true;
r = bus_socket_auth_write(b, "AGREE_UNIX_FD\r\n");
}
} else
r = bus_socket_auth_write(b, "ERROR\r\n");
if (r < 0)
return r;
b->auth_rbegin = e + 2 - (char*) b->rbuffer;
processed = true;
}
}
static int bus_socket_auth_verify(sd_bus *b) {
assert(b);
if (b->is_server)
return bus_socket_auth_verify_server(b);
else
return bus_socket_auth_verify_client(b);
}
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;
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;
bool handle_cmsg = false;
assert(b);
assert(b->state == BUS_AUTHENTICATING);
r = bus_socket_auth_verify(b);
if (r != 0)
return r;
n = MAX(256u, 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;
iov.iov_base = (uint8_t*) b->rbuffer + b->rbuffer_size;
iov.iov_len = n - b->rbuffer_size;
if (b->prefer_readv)
k = readv(b->input_fd, &iov, 1);
else {
zero(mh);
mh.msg_iov = &iov;
mh.msg_iovlen = 1;
mh.msg_control = &control;
mh.msg_controllen = sizeof(control);
k = recvmsg(b->input_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC);
if (k < 0 && errno == ENOTSOCK) {
b->prefer_readv = true;
k = readv(b->input_fd, &iov, 1);
} else
handle_cmsg = true;
}
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
if (k == 0)
return -ECONNRESET;
b->rbuffer_size += k;
if (handle_cmsg) {
for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg)) {
if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_RIGHTS) {
int j;
/* Whut? We received fds during the auth
* protocol? Somebody is playing games with
* us. Close them all, and fail */
j = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
close_many((int*) CMSG_DATA(cmsg), j);
return -EIO;
} else if (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_CREDENTIALS &&
cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred))) {
/* Ignore bogus data, which we might
* get on socketpair() sockets */
if (((struct ucred*) CMSG_DATA(cmsg))->pid != 0) {
memcpy(&b->ucred, CMSG_DATA(cmsg), sizeof(struct ucred));
b->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);
if (l > 0) {
memcpy(&b->label, CMSG_DATA(cmsg), l);
b->label[l] = 0;
}
}
}
}
r = bus_socket_auth_verify(b);
if (r != 0)
return r;
return 1;
}
void bus_socket_setup(sd_bus *b) {
int enable;
assert(b);
/* Enable SO_PASSCRED + SO_PASSEC. We try this on any
* socket, just in case. */
enable = !b->bus_client;
(void) setsockopt(b->input_fd, SOL_SOCKET, SO_PASSCRED, &enable, sizeof(enable));
enable = !b->bus_client && (b->attach_flags & KDBUS_ATTACH_SECLABEL);
(void) setsockopt(b->input_fd, SOL_SOCKET, SO_PASSSEC, &enable, sizeof(enable));
/* Increase the buffers to 8 MB */
fd_inc_rcvbuf(b->input_fd, SNDBUF_SIZE);
fd_inc_sndbuf(b->output_fd, SNDBUF_SIZE);
b->is_kernel = false;
b->message_version = 1;
b->message_endian = 0;
}
static void bus_get_peercred(sd_bus *b) {
assert(b);
/* Get the peer for socketpair() sockets */
b->ucred_valid = getpeercred(b->input_fd, &b->ucred) >= 0;
}
static int bus_socket_start_auth_client(sd_bus *b) {
size_t l;
const char *auth_suffix, *auth_prefix;
assert(b);
if (b->anonymous_auth) {
auth_prefix = "\0AUTH ANONYMOUS ";
/* For ANONYMOUS auth we send some arbitrary "trace" string */
l = 9;
b->auth_buffer = hexmem("anonymous", l);
} else {
char text[DECIMAL_STR_MAX(uid_t) + 1];
auth_prefix = "\0AUTH EXTERNAL ";
xsprintf(text, UID_FMT, geteuid());
l = strlen(text);
b->auth_buffer = hexmem(text, l);
}
if (!b->auth_buffer)
return -ENOMEM;
if (b->hello_flags & KDBUS_HELLO_ACCEPT_FD)
auth_suffix = "\r\nNEGOTIATE_UNIX_FD\r\nBEGIN\r\n";
else
auth_suffix = "\r\nBEGIN\r\n";
b->auth_iovec[0].iov_base = (void*) auth_prefix;
b->auth_iovec[0].iov_len = 1 + strlen(auth_prefix + 1);
b->auth_iovec[1].iov_base = (void*) b->auth_buffer;
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);
return bus_socket_write_auth(b);
}
int bus_socket_start_auth(sd_bus *b) {
assert(b);
bus_get_peercred(b);
b->state = BUS_AUTHENTICATING;
b->auth_timeout = now(CLOCK_MONOTONIC) + BUS_DEFAULT_TIMEOUT;
if (sd_is_socket(b->input_fd, AF_UNIX, 0, 0) <= 0)
b->hello_flags &= ~KDBUS_HELLO_ACCEPT_FD;
if (b->output_fd != b->input_fd)
if (sd_is_socket(b->output_fd, AF_UNIX, 0, 0) <= 0)
b->hello_flags &= ~KDBUS_HELLO_ACCEPT_FD;
if (b->is_server)
return bus_socket_read_auth(b);
else
return bus_socket_start_auth_client(b);
}
int bus_socket_connect(sd_bus *b) {
int r;
assert(b);
assert(b->input_fd < 0);
assert(b->output_fd < 0);
assert(b->sockaddr.sa.sa_family != AF_UNSPEC);
b->input_fd = socket(b->sockaddr.sa.sa_family, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
if (b->input_fd < 0)
return -errno;
b->output_fd = b->input_fd;
bus_socket_setup(b);
r = connect(b->input_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], r;
pid_t pid;
assert(b);
assert(b->input_fd < 0);
assert(b->output_fd < 0);
assert(b->exec_path);
r = socketpair(AF_UNIX, SOCK_STREAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, s);
if (r < 0)
return -errno;
pid = fork();
if (pid < 0) {
safe_close_pair(s);
return -errno;
}
if (pid == 0) {
/* Child */
(void) reset_all_signal_handlers();
(void) reset_signal_mask();
close_all_fds(s+1, 1);
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)
safe_close(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);
}
safe_close(s[1]);
b->output_fd = b->input_fd = s[0];
bus_socket_setup(b);
return bus_socket_start_auth(b);
}
int bus_socket_take_fd(sd_bus *b) {
assert(b);
bus_socket_setup(b);
return bus_socket_start_auth(b);
}
int bus_socket_write_message(sd_bus *bus, sd_bus_message *m, size_t *idx) {
struct iovec *iov;
ssize_t k;
size_t n;
unsigned j;
int r;
assert(bus);
assert(m);
assert(idx);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
if (*idx >= BUS_MESSAGE_SIZE(m))
return 0;
r = bus_message_setup_iovec(m);
if (r < 0)
return r;
n = m->n_iovec * sizeof(struct iovec);
iov = alloca(n);
memcpy(iov, m->iovec, n);
j = 0;
iovec_advance(iov, &j, *idx);
if (bus->prefer_writev)
k = writev(bus->output_fd, iov, m->n_iovec);
else {
struct msghdr mh = {
.msg_iov = iov,
.msg_iovlen = m->n_iovec,
};
if (m->n_fds > 0) {
struct cmsghdr *control;
mh.msg_control = control = alloca(CMSG_SPACE(sizeof(int) * m->n_fds));
mh.msg_controllen = control->cmsg_len = CMSG_LEN(sizeof(int) * m->n_fds);
control->cmsg_level = SOL_SOCKET;
control->cmsg_type = SCM_RIGHTS;
memcpy(CMSG_DATA(control), m->fds, sizeof(int) * m->n_fds);
}
k = sendmsg(bus->output_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
if (k < 0 && errno == ENOTSOCK) {
bus->prefer_writev = true;
k = writev(bus->output_fd, iov, m->n_iovec);
}
}
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 == BUS_LITTLE_ENDIAN) {
a = le32toh(a);
b = le32toh(b);
} else if (e == 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 *t;
void *b;
int r;
assert(bus);
assert(bus->rbuffer_size >= size);
assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
r = bus_rqueue_make_room(bus);
if (r < 0)
return r;
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,
bus->rbuffer, size,
bus->fds, bus->n_fds,
NULL,
NULL,
&t);
if (r < 0) {
free(b);
return r;
}
bus->rbuffer = b;
bus->rbuffer_size -= size;
bus->fds = NULL;
bus->n_fds = 0;
bus->rqueue[bus->rqueue_size++] = t;
return 1;
}
int bus_socket_read_message(sd_bus *bus) {
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;
bool handle_cmsg = false;
assert(bus);
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);
b = realloc(bus->rbuffer, need);
if (!b)
return -ENOMEM;
bus->rbuffer = b;
iov.iov_base = (uint8_t*) bus->rbuffer + bus->rbuffer_size;
iov.iov_len = need - bus->rbuffer_size;
if (bus->prefer_readv)
k = readv(bus->input_fd, &iov, 1);
else {
zero(mh);
mh.msg_iov = &iov;
mh.msg_iovlen = 1;
mh.msg_control = &control;
mh.msg_controllen = sizeof(control);
k = recvmsg(bus->input_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC);
if (k < 0 && errno == ENOTSOCK) {
bus->prefer_readv = true;
k = readv(bus->input_fd, &iov, 1);
} else
handle_cmsg = true;
}
if (k < 0)
return errno == EAGAIN ? 0 : -errno;
if (k == 0)
return -ECONNRESET;
bus->rbuffer_size += k;
if (handle_cmsg) {
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);
if (!bus->can_fds) {
/* Whut? We received fds but this
* isn't actually enabled? Close them,
* and fail */
close_many((int*) CMSG_DATA(cmsg), n);
return -EIO;
}
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))) {
/* Ignore bogus data, which we might
* get on socketpair() sockets */
if (((struct ucred*) CMSG_DATA(cmsg))->pid != 0) {
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);
if (l > 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);
return 1;
}
int bus_socket_process_opening(sd_bus *b) {
int error = 0;
socklen_t slen = sizeof(error);
struct pollfd p = {
.fd = b->output_fd,
.events = POLLOUT,
};
int r;
assert(b->state == BUS_OPENING);
r = poll(&p, 1, 0);
if (r < 0)
return -errno;
if (!(p.revents & (POLLOUT|POLLERR|POLLHUP)))
return 0;
r = getsockopt(b->output_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);
}