stdio-bridge: rework stdio bridge to use libsystemd-bus

This commit is contained in:
Lennart Poettering 2013-04-01 03:28:42 +02:00
parent adee69fa7a
commit d51539b182
2 changed files with 157 additions and 289 deletions

View file

@ -1612,7 +1612,9 @@ systemd_stdio_bridge_SOURCES = \
src/stdio-bridge/stdio-bridge.c
systemd_stdio_bridge_LDADD = \
libsystemd-shared.la
libsystemd-shared.la \
libsystemd-bus.la \
libsystemd-daemon.la
# ------------------------------------------------------------------------------
systemd_tty_ask_password_agent_SOURCES = \

View file

@ -26,121 +26,22 @@
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/epoll.h>
#include <sys/poll.h>
#include <stddef.h>
#include "log.h"
#include "util.h"
#include "socket-util.h"
#define BUFFER_SIZE (64*1024)
#define EXTRA_SIZE 16
static bool initial_nul = false;
static bool auth_over = false;
static void format_uid(char *buf, size_t l) {
char text[20 + 1]; /* enough space for a 64bit integer plus NUL */
unsigned j;
assert(l > 0);
snprintf(text, sizeof(text)-1, "%llu", (unsigned long long) geteuid());
char_array_0(text);
memset(buf, 0, l);
for (j = 0; text[j] && j*2+2 < l; j++) {
buf[j*2] = hexchar(text[j] >> 4);
buf[j*2+1] = hexchar(text[j] & 0xF);
}
buf[j*2] = 0;
}
static size_t patch_in_line(char *line, size_t l, size_t left) {
size_t r;
if (line[0] == 0 && !initial_nul) {
initial_nul = true;
line += 1;
l -= 1;
r = 1;
} else
r = 0;
if (l == 5 && strneq(line, "BEGIN", 5)) {
r += l;
auth_over = true;
} else if (l == 17 && strneq(line, "NEGOTIATE_UNIX_FD", 17)) {
memmove(line + 13, line + 17, left);
memcpy(line, "NEGOTIATE_NOP", 13);
r += 13;
} else if (l >= 14 && strneq(line, "AUTH EXTERNAL ", 14)) {
char uid[20*2 + 1];
size_t len;
format_uid(uid, sizeof(uid));
len = strlen(uid);
assert(len <= EXTRA_SIZE);
memmove(line + 14 + len, line + l, left);
memcpy(line + 14, uid, len);
r += 14 + len;
} else
r += l;
return r;
}
static size_t patch_in_buffer(char* in_buffer, size_t *in_buffer_full) {
size_t i, good = 0;
if (*in_buffer_full <= 0)
return *in_buffer_full;
/* If authentication is done, we don't touch anything anymore */
if (auth_over)
return *in_buffer_full;
if (*in_buffer_full < 2)
return 0;
for (i = 0; i <= *in_buffer_full - 2; i ++) {
/* Fully lines can be send on */
if (in_buffer[i] == '\r' && in_buffer[i+1] == '\n') {
if (i > good) {
size_t old_length, new_length;
old_length = i - good;
new_length = patch_in_line(in_buffer+good, old_length, *in_buffer_full - i);
*in_buffer_full = *in_buffer_full + new_length - old_length;
good += new_length + 2;
} else
good = i+2;
}
if (auth_over)
break;
}
return good;
}
#include "sd-daemon.h"
#include "sd-bus.h"
#include "bus-internal.h"
#include "bus-message.h"
int main(int argc, char *argv[]) {
int r = EXIT_FAILURE, fd = -1, ep = -1;
union sockaddr_union sa;
char in_buffer[BUFFER_SIZE+EXTRA_SIZE], out_buffer[BUFFER_SIZE+EXTRA_SIZE];
size_t in_buffer_full = 0, out_buffer_full = 0;
struct epoll_event stdin_ev, stdout_ev, fd_ev;
bool stdin_readable = false, stdout_writable = false, fd_readable = false, fd_writable = false;
bool stdin_rhup = false, stdout_whup = false, fd_rhup = false, fd_whup = false;
_cleanup_bus_unref_ sd_bus *a = NULL, *b = NULL;
sd_id128_t server_id;
bool is_unix;
int r;
if (argc > 1) {
log_error("This program takes no argument.");
@ -151,217 +52,182 @@ int main(int argc, char *argv[]) {
log_parse_environment();
log_open();
if ((fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0)) < 0) {
log_error("Failed to create socket: %s", strerror(errno));
is_unix =
sd_is_socket(STDIN_FILENO, AF_UNIX, 0, 0) > 0 &&
sd_is_socket(STDOUT_FILENO, AF_UNIX, 0, 0) > 0;
r = sd_bus_new(&a);
if (r < 0) {
log_error("Failed to allocate bus: %s", strerror(-r));
goto finish;
}
zero(sa);
sa.un.sun_family = AF_UNIX;
strncpy(sa.un.sun_path, "/run/dbus/system_bus_socket", sizeof(sa.un.sun_path));
if (connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) {
log_error("Failed to connect: %m");
r = sd_bus_set_address(a, "unix:path=/run/dbus/system_bus_socket");
if (r < 0) {
log_error("Failed to set address to connect to: %s", strerror(-r));
goto finish;
}
fd_nonblock(STDIN_FILENO, 1);
fd_nonblock(STDOUT_FILENO, 1);
if ((ep = epoll_create1(EPOLL_CLOEXEC)) < 0) {
log_error("Failed to create epoll: %m");
r = sd_bus_set_negotiate_fds(a, is_unix);
if (r < 0) {
log_error("Failed to set FD negotiation: %s", strerror(-r));
goto finish;
}
zero(stdin_ev);
stdin_ev.events = EPOLLIN|EPOLLET;
stdin_ev.data.fd = STDIN_FILENO;
zero(stdout_ev);
stdout_ev.events = EPOLLOUT|EPOLLET;
stdout_ev.data.fd = STDOUT_FILENO;
zero(fd_ev);
fd_ev.events = EPOLLIN|EPOLLOUT|EPOLLET;
fd_ev.data.fd = fd;
if (epoll_ctl(ep, EPOLL_CTL_ADD, STDIN_FILENO, &stdin_ev) < 0 ||
epoll_ctl(ep, EPOLL_CTL_ADD, STDOUT_FILENO, &stdout_ev) < 0 ||
epoll_ctl(ep, EPOLL_CTL_ADD, fd, &fd_ev) < 0) {
log_error("Failed to regiser fds in epoll: %m");
r = sd_bus_start(a);
if (r < 0) {
log_error("Failed to start bus client: %s", strerror(-r));
goto finish;
}
do {
struct epoll_event ev[16];
ssize_t k;
int i, nfds;
r = sd_bus_get_server_id(a, &server_id);
if (r < 0) {
log_error("Failed to get server ID: %s", strerror(-r));
goto finish;
}
if ((nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), -1)) < 0) {
r = sd_bus_new(&b);
if (r < 0) {
log_error("Failed to allocate bus: %s", strerror(-r));
goto finish;
}
if (errno == EINTR || errno == EAGAIN)
continue;
r = sd_bus_set_fd(b, STDIN_FILENO, STDOUT_FILENO);
if (r < 0) {
log_error("Failed to set fds: %s", strerror(-r));
goto finish;
}
log_error("epoll_wait(): %m");
r = sd_bus_set_server(b, 1, server_id);
if (r < 0) {
log_error("Failed to set server mode: %s", strerror(-r));
goto finish;
}
r = sd_bus_set_negotiate_fds(b, is_unix);
if (r < 0) {
log_error("Failed to set FD negotiation: %s", strerror(-r));
goto finish;
}
r = sd_bus_set_anonymous(b, true);
if (r < 0) {
log_error("Failed to set anonymous authentication: %s", strerror(-r));
goto finish;
}
r = sd_bus_start(b);
if (r < 0) {
log_error("Failed to start bus client: %s", strerror(-r));
goto finish;
}
for (;;) {
_cleanup_bus_message_unref_ sd_bus_message *m = NULL;
struct pollfd p[3];
int events_a, events_b, fd;
uint64_t timeout_a, timeout_b, t;
struct timespec _ts, *ts;
r = sd_bus_process(a, &m);
if (r < 0) {
log_error("Failed to process bus: %s", strerror(-r));
goto finish;
}
assert(nfds >= 1);
for (i = 0; i < nfds; i++) {
if (ev[i].data.fd == STDIN_FILENO) {
if (!stdin_rhup && (ev[i].events & (EPOLLHUP|EPOLLIN)))
stdin_readable = true;
} else if (ev[i].data.fd == STDOUT_FILENO) {
if (ev[i].events & EPOLLHUP) {
stdout_writable = false;
stdout_whup = true;
}
if (!stdout_whup && (ev[i].events & EPOLLOUT))
stdout_writable = true;
} else if (ev[i].data.fd == fd) {
if (ev[i].events & EPOLLHUP) {
fd_writable = false;
fd_whup = true;
}
if (!fd_rhup && (ev[i].events & (EPOLLHUP|EPOLLIN)))
fd_readable = true;
if (!fd_whup && (ev[i].events & EPOLLOUT))
fd_writable = true;
if (m) {
r = sd_bus_send(b, m, NULL);
if (r < 0) {
log_error("Failed to send message: %s", strerror(-r));
goto finish;
}
}
while ((stdin_readable && in_buffer_full <= 0) ||
(fd_writable && patch_in_buffer(in_buffer, &in_buffer_full) > 0) ||
(fd_readable && out_buffer_full <= 0) ||
(stdout_writable && out_buffer_full > 0)) {
if (r > 0)
continue;
size_t in_buffer_good = 0;
r = sd_bus_process(b, &m);
if (r < 0) {
log_error("Failed to process bus: %s", strerror(-r));
goto finish;
}
if (stdin_readable && in_buffer_full < BUFFER_SIZE) {
if ((k = read(STDIN_FILENO, in_buffer + in_buffer_full, BUFFER_SIZE - in_buffer_full)) < 0) {
if (errno == EAGAIN)
stdin_readable = false;
else if (errno == EPIPE || errno == ECONNRESET)
k = 0;
else {
log_error("read(): %m");
goto finish;
}
} else
in_buffer_full += (size_t) k;
if (k == 0) {
stdin_rhup = true;
stdin_readable = false;
shutdown(STDIN_FILENO, SHUT_RD);
close_nointr_nofail(STDIN_FILENO);
}
}
in_buffer_good = patch_in_buffer(in_buffer, &in_buffer_full);
if (fd_writable && in_buffer_good > 0) {
if ((k = write(fd, in_buffer, in_buffer_good)) < 0) {
if (errno == EAGAIN)
fd_writable = false;
else if (errno == EPIPE || errno == ECONNRESET) {
fd_whup = true;
fd_writable = false;
shutdown(fd, SHUT_WR);
} else {
log_error("write(): %m");
goto finish;
}
} else {
assert(in_buffer_full >= (size_t) k);
memmove(in_buffer, in_buffer + k, in_buffer_full - k);
in_buffer_full -= k;
}
}
if (fd_readable && out_buffer_full < BUFFER_SIZE) {
if ((k = read(fd, out_buffer + out_buffer_full, BUFFER_SIZE - out_buffer_full)) < 0) {
if (errno == EAGAIN)
fd_readable = false;
else if (errno == EPIPE || errno == ECONNRESET)
k = 0;
else {
log_error("read(): %m");
goto finish;
}
} else
out_buffer_full += (size_t) k;
if (k == 0) {
fd_rhup = true;
fd_readable = false;
shutdown(fd, SHUT_RD);
}
}
if (stdout_writable && out_buffer_full > 0) {
if ((k = write(STDOUT_FILENO, out_buffer, out_buffer_full)) < 0) {
if (errno == EAGAIN)
stdout_writable = false;
else if (errno == EPIPE || errno == ECONNRESET) {
stdout_whup = true;
stdout_writable = false;
shutdown(STDOUT_FILENO, SHUT_WR);
close_nointr(STDOUT_FILENO);
} else {
log_error("write(): %m");
goto finish;
}
} else {
assert(out_buffer_full >= (size_t) k);
memmove(out_buffer, out_buffer + k, out_buffer_full - k);
out_buffer_full -= k;
}
if (m) {
r = sd_bus_send(a, m, NULL);
if (r < 0) {
log_error("Failed to send message: %s", strerror(-r));
goto finish;
}
}
if (stdin_rhup && in_buffer_full <= 0 && !fd_whup) {
fd_whup = true;
fd_writable = false;
shutdown(fd, SHUT_WR);
if (r > 0)
continue;
fd = sd_bus_get_fd(a);
if (fd < 0) {
log_error("Failed to get fd: %s", strerror(-r));
goto finish;
}
if (fd_rhup && out_buffer_full <= 0 && !stdout_whup) {
stdout_whup = true;
stdout_writable = false;
shutdown(STDOUT_FILENO, SHUT_WR);
close_nointr(STDOUT_FILENO);
events_a = sd_bus_get_events(a);
if (events_a < 0) {
log_error("Failed to get events mask: %s", strerror(-r));
goto finish;
}
} while (!stdout_whup || !fd_whup);
r = sd_bus_get_timeout(a, &timeout_a);
if (r < 0) {
log_error("Failed to get timeout: %s", strerror(-r));
goto finish;
}
r = EXIT_SUCCESS;
events_b = sd_bus_get_events(b);
if (events_b < 0) {
log_error("Failed to get events mask: %s", strerror(-r));
goto finish;
}
r = sd_bus_get_timeout(b, &timeout_b);
if (r < 0) {
log_error("Failed to get timeout: %s", strerror(-r));
goto finish;
}
t = timeout_a;
if (t == (uint64_t) -1 || (timeout_b != (uint64_t) -1 && timeout_b < timeout_a))
t = timeout_b;
if (t == (uint64_t) -1)
ts = NULL;
else {
usec_t nw;
nw = now(CLOCK_MONOTONIC);
if (t > nw)
t -= nw;
else
t = 0;
ts = timespec_store(&_ts, t);
}
zero(p);
p[0].fd = fd;
p[0].events = events_a;
p[1].fd = STDIN_FILENO;
p[1].events = events_b & POLLIN;
p[2].fd = STDOUT_FILENO;
p[2].events = events_b & POLLOUT;
r = ppoll(p, ELEMENTSOF(p), ts, NULL);
if (r < 0) {
log_error("ppoll() failed: %m");
goto finish;
}
}
r = 0;
finish:
if (fd >= 0)
close_nointr_nofail(fd);
if (ep >= 0)
close_nointr_nofail(ep);
return r;
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}