mirror of
https://github.com/tmate-io/tmate-ssh-server.git
synced 2020-11-18 19:53:51 -08:00
Refactor code
This commit is contained in:
Nicolas Viennot
parent
6a951aa9f7
commit
cd3ee3ee4d
@ -175,18 +175,19 @@ dist_tmate_ssh_server_SOURCES = \
|
||||
signal.c \
|
||||
status.c \
|
||||
style.c \
|
||||
tmate-debug.c \
|
||||
tmate-daemon-decoder.c \
|
||||
tmate-daemon-encoder.c \
|
||||
tmate-daemon-legacy.c \
|
||||
tmate-msgpack.c \
|
||||
tmate-websocket.c \
|
||||
tmate-debug.c \
|
||||
tmate-main.c \
|
||||
tmate-msgpack.c \
|
||||
tmate-rand.c \
|
||||
tmate-ssh-client-pty.c \
|
||||
tmate-ssh-daemon.c \
|
||||
tmate-ssh-exec.c \
|
||||
tmate-ssh-latency.c \
|
||||
tmate-ssh-server.c \
|
||||
tmate-websocket.c \
|
||||
tmux.c \
|
||||
tty-acs.c \
|
||||
tty-keys.c \
|
||||
|
||||
320
tmate-main.c
320
tmate-main.c
@ -21,18 +21,8 @@
|
||||
#include <signal.h>
|
||||
#include "tmate.h"
|
||||
|
||||
struct tmate_session _tmate_session, *tmate_session = &_tmate_session;
|
||||
|
||||
extern FILE *log_file;
|
||||
|
||||
static char *cmdline;
|
||||
static char *cmdline_end;
|
||||
static int dev_urandom_fd;
|
||||
|
||||
extern int server_create_socket(void);
|
||||
extern int client_connect(struct event_base *base, const char *path, int start_server);
|
||||
|
||||
static void tmate_spawn_exec(struct tmate_session *session);
|
||||
|
||||
struct tmate_settings _tmate_settings = {
|
||||
.keys_dir = TMATE_SSH_DEFAULT_KEYS_DIR,
|
||||
@ -50,51 +40,6 @@ struct tmate_settings _tmate_settings = {
|
||||
|
||||
struct tmate_settings *tmate_settings = &_tmate_settings;
|
||||
|
||||
void tmate_get_random_bytes(void *buffer, ssize_t len)
|
||||
{
|
||||
if (read(dev_urandom_fd, buffer, len) != len)
|
||||
tmate_fatal("Cannot read from /dev/urandom");
|
||||
}
|
||||
|
||||
long tmate_get_random_long(void)
|
||||
{
|
||||
long val;
|
||||
tmate_get_random_bytes(&val, sizeof(val));
|
||||
return val;
|
||||
}
|
||||
|
||||
#define RS_BUF_SIZE 256
|
||||
|
||||
struct random_stream {
|
||||
char bytes[RS_BUF_SIZE];
|
||||
off_t pos;
|
||||
};
|
||||
|
||||
static void random_stream_init(struct random_stream *rs)
|
||||
{
|
||||
rs->pos = RS_BUF_SIZE;
|
||||
}
|
||||
|
||||
static char *random_stream_get(struct random_stream *rs, size_t count)
|
||||
{
|
||||
char *ret;
|
||||
|
||||
if (count > RS_BUF_SIZE) {
|
||||
tmate_fatal("buffer too small");
|
||||
}
|
||||
|
||||
if (rs->pos + count > RS_BUF_SIZE) {
|
||||
tmate_get_random_bytes(rs->bytes, RS_BUF_SIZE);
|
||||
rs->pos = 0;
|
||||
}
|
||||
|
||||
|
||||
ret = &rs->bytes[rs->pos];
|
||||
rs->pos += count;
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
||||
extern int server_fd;
|
||||
extern void server_send_exit(void);
|
||||
void request_server_termination(void)
|
||||
@ -214,9 +159,7 @@ int main(int argc, char **argv, char **envp)
|
||||
|
||||
tmate_preload_trace_lib();
|
||||
tmate_catch_sigsegv();
|
||||
|
||||
if ((dev_urandom_fd = open("/dev/urandom", O_RDONLY)) < 0)
|
||||
tmate_fatal("Cannot open /dev/urandom");
|
||||
tmate_init_rand();
|
||||
|
||||
if ((mkdir(TMATE_WORKDIR, 0701) < 0 && errno != EEXIST) ||
|
||||
(mkdir(TMATE_WORKDIR "/sessions", 0703) < 0 && errno != EEXIST) ||
|
||||
@ -234,41 +177,17 @@ int main(int argc, char **argv, char **envp)
|
||||
return 0;
|
||||
}
|
||||
|
||||
static char tmate_token_digits[] = "abcdefghjkmnpqrstuvwxyz"
|
||||
"ABCDEFGHJKLMNPQRSTUVWXYZ"
|
||||
"23456789";
|
||||
|
||||
#define NUM_DIGITS (sizeof(tmate_token_digits) - 1)
|
||||
|
||||
static char *get_random_token(void)
|
||||
{
|
||||
struct random_stream rs;
|
||||
char *token = xmalloc(TMATE_TOKEN_LEN + 1);
|
||||
int i;
|
||||
unsigned char c;
|
||||
|
||||
random_stream_init(&rs);
|
||||
|
||||
for (i = 0; i < TMATE_TOKEN_LEN; i++) {
|
||||
do {
|
||||
c = *random_stream_get(&rs, 1);
|
||||
} while (c >= NUM_DIGITS);
|
||||
|
||||
token[i] = tmate_token_digits[c];
|
||||
}
|
||||
|
||||
token[i] = 0;
|
||||
|
||||
return token;
|
||||
}
|
||||
|
||||
void set_session_token(struct tmate_session *session,
|
||||
const char *token)
|
||||
char *get_socket_path(const char *token)
|
||||
{
|
||||
char *path;
|
||||
session->session_token = xstrdup(token);
|
||||
xasprintf(&path, TMATE_WORKDIR "/sessions/%s", token);
|
||||
socket_path = path;
|
||||
return path;
|
||||
}
|
||||
|
||||
void set_session_token(struct tmate_session *session, const char *token)
|
||||
{
|
||||
session->session_token = xstrdup(token);
|
||||
socket_path = get_socket_path(token);
|
||||
|
||||
xasprintf((char **)&session->obfuscated_session_token, "%.4s...",
|
||||
session->session_token);
|
||||
@ -280,71 +199,7 @@ void set_session_token(struct tmate_session *session,
|
||||
session->ssh_client.ip_address);
|
||||
}
|
||||
|
||||
static void create_session_ro_symlink(struct tmate_session *session)
|
||||
{
|
||||
char *tmp, *token, *session_ro_path;
|
||||
|
||||
#ifdef DEVENV
|
||||
tmp = xstrdup("READONLYTOKENFORDEVENV000");
|
||||
#else
|
||||
tmp = get_random_token();
|
||||
#endif
|
||||
xasprintf(&token, "ro-%s", tmp);
|
||||
free(tmp);
|
||||
|
||||
session->session_token_ro = token;
|
||||
|
||||
xasprintf(&session_ro_path, TMATE_WORKDIR "/sessions/%s",
|
||||
session->session_token_ro);
|
||||
|
||||
unlink(session_ro_path);
|
||||
if (symlink(session->session_token, session_ro_path) < 0)
|
||||
tmate_fatal("Cannot create read-only symlink");
|
||||
free(session_ro_path);
|
||||
}
|
||||
|
||||
static int validate_token(const char *token)
|
||||
{
|
||||
int len;
|
||||
int i;
|
||||
|
||||
if (!memcmp("ro-", token, 3))
|
||||
token += 3;
|
||||
|
||||
len = strlen(token);
|
||||
|
||||
if (len != TMATE_TOKEN_LEN)
|
||||
return -1;
|
||||
|
||||
for (i = 0; i < len; i++) {
|
||||
if (!strchr(tmate_token_digits, token[i]))
|
||||
return -1;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void random_sleep(void)
|
||||
{
|
||||
struct timespec ts;
|
||||
ts.tv_sec = 0;
|
||||
ts.tv_nsec = 50000000 + (tmate_get_random_long() % 150000000);
|
||||
nanosleep(&ts, NULL);
|
||||
}
|
||||
|
||||
static void ssh_echo(struct tmate_ssh_client *ssh_client,
|
||||
const char *str)
|
||||
{
|
||||
ssh_channel_write(ssh_client->channel, str, strlen(str));
|
||||
}
|
||||
|
||||
#define BAD_TOKEN_ERROR_STR \
|
||||
"Invalid session token" "\r\n"
|
||||
|
||||
#define EXPIRED_TOKEN_ERROR_STR \
|
||||
"Invalid or expired session token" "\r\n"
|
||||
|
||||
static void close_fds_except(int *fd_to_preserve, int num_fds)
|
||||
void close_fds_except(int *fd_to_preserve, int num_fds)
|
||||
{
|
||||
int fd, i, preserve;
|
||||
|
||||
@ -359,7 +214,7 @@ static void close_fds_except(int *fd_to_preserve, int num_fds)
|
||||
}
|
||||
}
|
||||
|
||||
static void jail(void)
|
||||
void get_in_jail(void)
|
||||
{
|
||||
struct passwd *pw;
|
||||
uid_t uid;
|
||||
@ -418,161 +273,10 @@ static void jail(void)
|
||||
TMATE_JAIL_USER, uid, gid, TMATE_WORKDIR "/jail");
|
||||
}
|
||||
|
||||
static void setup_ncurse(int fd, const char *name)
|
||||
void setup_ncurse(int fd, const char *name)
|
||||
{
|
||||
int error;
|
||||
if (setupterm((char *)name, fd, &error) != OK)
|
||||
tmate_fatal("Cannot setup terminal");
|
||||
}
|
||||
|
||||
static void handle_sigterm(__unused int sig)
|
||||
{
|
||||
request_server_termination();
|
||||
}
|
||||
|
||||
static void tmate_spawn_daemon(struct tmate_session *session)
|
||||
{
|
||||
struct tmate_ssh_client *client = &session->ssh_client;
|
||||
char *token;
|
||||
|
||||
#ifdef DEVENV
|
||||
token = xstrdup("SUPERSECURETOKENFORDEVENV");
|
||||
#else
|
||||
token = get_random_token();
|
||||
#endif
|
||||
|
||||
set_session_token(session, token);
|
||||
free(token);
|
||||
|
||||
tmate_info("Spawning daemon for %s at %s (%s)",
|
||||
client->username, client->ip_address, client->pubkey);
|
||||
|
||||
session->tmux_socket_fd = server_create_socket();
|
||||
if (session->tmux_socket_fd < 0)
|
||||
tmate_fatal("Cannot create to the tmux socket");
|
||||
|
||||
create_session_ro_symlink(session);
|
||||
|
||||
/*
|
||||
* Needed to initialize the database used in tty-term.c.
|
||||
* We won't have access to it once in the jail.
|
||||
*/
|
||||
setup_ncurse(STDOUT_FILENO, "screen-256color");
|
||||
|
||||
tmate_daemon_init(session);
|
||||
|
||||
close_fds_except((int[]){session->tmux_socket_fd,
|
||||
ssh_get_fd(session->ssh_client.session),
|
||||
log_file ? fileno(log_file) : -1,
|
||||
session->websocket_fd}, 4);
|
||||
|
||||
jail();
|
||||
event_reinit(session->ev_base);
|
||||
|
||||
tmux_server_init();
|
||||
signal(SIGTERM, handle_sigterm);
|
||||
server_start(session->ev_base, -1, NULL);
|
||||
/* never reached */
|
||||
}
|
||||
|
||||
static void tmate_spawn_pty_client(struct tmate_session *session)
|
||||
{
|
||||
struct tmate_ssh_client *client = &session->ssh_client;
|
||||
char *argv_rw[] = {(char *)"attach", NULL};
|
||||
char *argv_ro[] = {(char *)"attach", (char *)"-r", NULL};
|
||||
char **argv = argv_rw;
|
||||
int argc = 1;
|
||||
char *token = client->username;
|
||||
struct stat fstat;
|
||||
int slave_pty;
|
||||
int ret;
|
||||
|
||||
if (validate_token(token) < 0) {
|
||||
ssh_echo(client, BAD_TOKEN_ERROR_STR);
|
||||
tmate_fatal("Invalid token");
|
||||
}
|
||||
|
||||
set_session_token(session, token);
|
||||
|
||||
tmate_info("Spawning pty client for %s (%s)",
|
||||
client->ip_address, client->pubkey);
|
||||
|
||||
session->tmux_socket_fd = client_connect(session->ev_base, socket_path, 0);
|
||||
if (session->tmux_socket_fd < 0) {
|
||||
if (tmate_has_websocket()) {
|
||||
/* Turn the response into an exec to show a better error */
|
||||
client->exec_command = xstrdup("explain-session-not-found");
|
||||
tmate_spawn_exec(session);
|
||||
/* No return */
|
||||
}
|
||||
|
||||
random_sleep(); /* for making timing attacks harder */
|
||||
ssh_echo(client, EXPIRED_TOKEN_ERROR_STR);
|
||||
tmate_fatal("Expired token");
|
||||
}
|
||||
|
||||
/*
|
||||
* If we are connecting through a symlink, it means that we are a
|
||||
* readonly client.
|
||||
* 1) We mark the client as CLIENT_READONLY on the server
|
||||
* 2) We prevent any input (aside from the window size) to go through
|
||||
* to the server.
|
||||
*/
|
||||
session->readonly = false;
|
||||
if (lstat(socket_path, &fstat) < 0)
|
||||
tmate_fatal("Cannot fstat()");
|
||||
if (S_ISLNK(fstat.st_mode)) {
|
||||
session->readonly = true;
|
||||
argv = argv_ro;
|
||||
argc = 2;
|
||||
}
|
||||
|
||||
if (openpty(&session->pty, &slave_pty, NULL, NULL, NULL) < 0)
|
||||
tmate_fatal("Cannot allocate pty");
|
||||
|
||||
dup2(slave_pty, STDIN_FILENO);
|
||||
dup2(slave_pty, STDOUT_FILENO);
|
||||
dup2(slave_pty, STDERR_FILENO);
|
||||
|
||||
setup_ncurse(slave_pty, "screen-256color");
|
||||
|
||||
tmate_client_pty_init(session);
|
||||
|
||||
/* the unused session->websocket_fd will get closed automatically */
|
||||
|
||||
close_fds_except((int[]){STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO,
|
||||
session->tmux_socket_fd,
|
||||
ssh_get_fd(session->ssh_client.session),
|
||||
session->pty, log_file ? fileno(log_file) : -1}, 7);
|
||||
jail();
|
||||
event_reinit(session->ev_base);
|
||||
|
||||
ret = client_main(session->ev_base, argc, argv,
|
||||
CLIENT_UTF8 | CLIENT_256COLOURS, NULL);
|
||||
tmate_flush_pty(session);
|
||||
exit(ret);
|
||||
}
|
||||
|
||||
static void tmate_spawn_exec(struct tmate_session *session)
|
||||
{
|
||||
close_fds_except((int[]){ssh_get_fd(session->ssh_client.session),
|
||||
log_file ? fileno(log_file) : -1,
|
||||
session->websocket_fd}, 3);
|
||||
jail();
|
||||
event_reinit(session->ev_base);
|
||||
|
||||
tmate_client_exec_init(session);
|
||||
|
||||
if (event_base_dispatch(session->ev_base) < 0)
|
||||
tmate_fatal("Cannot run event loop");
|
||||
exit(0);
|
||||
}
|
||||
|
||||
void tmate_spawn(struct tmate_session *session)
|
||||
{
|
||||
switch (session->ssh_client.role) {
|
||||
case TMATE_ROLE_DAEMON: tmate_spawn_daemon(session); break;
|
||||
case TMATE_ROLE_PTY_CLIENT: tmate_spawn_pty_client(session); break;
|
||||
case TMATE_ROLE_EXEC: tmate_spawn_exec(session); break;
|
||||
}
|
||||
}
|
||||
|
||||
47
tmate-rand.c
Normal file
47
tmate-rand.c
Normal file
@ -0,0 +1,47 @@
|
||||
#include "tmate.h"
|
||||
#include <fcntl.h>
|
||||
|
||||
static int dev_urandom_fd;
|
||||
|
||||
void tmate_init_rand(void)
|
||||
{
|
||||
if ((dev_urandom_fd = open("/dev/urandom", O_RDONLY)) < 0)
|
||||
tmate_fatal("Cannot open /dev/urandom");
|
||||
}
|
||||
|
||||
void tmate_get_random_bytes(void *buffer, ssize_t len)
|
||||
{
|
||||
if (read(dev_urandom_fd, buffer, len) != len)
|
||||
tmate_fatal("Cannot read from /dev/urandom");
|
||||
}
|
||||
|
||||
long tmate_get_random_long(void)
|
||||
{
|
||||
long val;
|
||||
tmate_get_random_bytes(&val, sizeof(val));
|
||||
return val;
|
||||
}
|
||||
|
||||
void random_stream_init(struct random_stream *rs)
|
||||
{
|
||||
rs->pos = RS_BUF_SIZE;
|
||||
}
|
||||
|
||||
char *random_stream_get(struct random_stream *rs, size_t count)
|
||||
{
|
||||
char *ret;
|
||||
|
||||
if (count > RS_BUF_SIZE) {
|
||||
tmate_fatal("buffer too small");
|
||||
}
|
||||
|
||||
if (rs->pos + count > RS_BUF_SIZE) {
|
||||
tmate_get_random_bytes(rs->bytes, RS_BUF_SIZE);
|
||||
rs->pos = 0;
|
||||
}
|
||||
|
||||
|
||||
ret = &rs->bytes[rs->pos];
|
||||
rs->pos += count;
|
||||
return ret;
|
||||
}
|
||||
@ -1,11 +1,10 @@
|
||||
#include <libssh/server.h>
|
||||
#include <errno.h>
|
||||
#include <sys/ioctl.h>
|
||||
#include <sys/stat.h>
|
||||
#include <signal.h>
|
||||
#include "tmate.h"
|
||||
|
||||
extern void client_signal(int sig);
|
||||
|
||||
static int on_ssh_channel_read(__unused ssh_session _session,
|
||||
__unused ssh_channel channel,
|
||||
void *_data, uint32_t total_len,
|
||||
@ -85,13 +84,13 @@ static void __on_pty_event(__unused evutil_socket_t fd, __unused short what, voi
|
||||
on_pty_event(arg);
|
||||
}
|
||||
|
||||
void tmate_flush_pty(struct tmate_session *session)
|
||||
static void tmate_flush_pty(struct tmate_session *session)
|
||||
{
|
||||
on_pty_event(session);
|
||||
close(session->pty);
|
||||
}
|
||||
|
||||
void tmate_client_pty_init(struct tmate_session *session)
|
||||
static void tmate_client_pty_init(struct tmate_session *session)
|
||||
{
|
||||
struct tmate_ssh_client *client = &session->ssh_client;
|
||||
|
||||
@ -111,3 +110,130 @@ void tmate_client_pty_init(struct tmate_session *session)
|
||||
EV_READ | EV_PERSIST, __on_pty_event, session);
|
||||
event_add(&session->ev_pty, NULL);
|
||||
}
|
||||
|
||||
static void random_sleep(void)
|
||||
{
|
||||
struct timespec ts;
|
||||
ts.tv_sec = 0;
|
||||
ts.tv_nsec = 50000000 + (tmate_get_random_long() % 150000000);
|
||||
nanosleep(&ts, NULL);
|
||||
}
|
||||
|
||||
#define BAD_TOKEN_ERROR_STR \
|
||||
"Invalid session token" "\r\n"
|
||||
|
||||
#define EXPIRED_TOKEN_ERROR_STR \
|
||||
"Invalid or expired session token" "\r\n"
|
||||
|
||||
static void ssh_echo(struct tmate_ssh_client *ssh_client,
|
||||
const char *str)
|
||||
{
|
||||
ssh_channel_write(ssh_client->channel, str, strlen(str));
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* Session tokens are filesystem sensitive,
|
||||
* so we must be very careful with / and .
|
||||
*/
|
||||
static char valid_digits[] = "abcdefghjklmnopqrstuvwxyz"
|
||||
"ABCDEFGHJKLMNOPQRSTUVWXYZ"
|
||||
"0123456789-_";
|
||||
|
||||
int tmate_validated_session_token(const char *token)
|
||||
{
|
||||
int len;
|
||||
int i;
|
||||
|
||||
if (!memcmp("ro-", token, 3))
|
||||
token += 3;
|
||||
|
||||
len = strlen(token);
|
||||
|
||||
if (len != TMATE_TOKEN_LEN)
|
||||
return -1;
|
||||
|
||||
for (i = 0; i < len; i++) {
|
||||
if (!strchr(valid_digits, token[i]))
|
||||
return -1;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
void tmate_spawn_pty_client(struct tmate_session *session)
|
||||
{
|
||||
struct tmate_ssh_client *client = &session->ssh_client;
|
||||
char *argv_rw[] = {(char *)"attach", NULL};
|
||||
char *argv_ro[] = {(char *)"attach", (char *)"-r", NULL};
|
||||
char **argv = argv_rw;
|
||||
int argc = 1;
|
||||
char *token = client->username;
|
||||
struct stat fstat;
|
||||
int slave_pty;
|
||||
int ret;
|
||||
|
||||
if (tmate_validated_session_token(token) < 0) {
|
||||
ssh_echo(client, BAD_TOKEN_ERROR_STR);
|
||||
tmate_fatal("Invalid token");
|
||||
}
|
||||
|
||||
set_session_token(session, token);
|
||||
|
||||
tmate_info("Spawning pty client for %s (%s)",
|
||||
client->ip_address, client->pubkey);
|
||||
|
||||
session->tmux_socket_fd = client_connect(session->ev_base, socket_path, 0);
|
||||
if (session->tmux_socket_fd < 0) {
|
||||
if (tmate_has_websocket()) {
|
||||
/* Turn the response into an exec to show a better error */
|
||||
client->exec_command = xstrdup("explain-session-not-found");
|
||||
tmate_spawn_exec(session);
|
||||
/* No return */
|
||||
}
|
||||
|
||||
random_sleep(); /* for making timing attacks harder */
|
||||
ssh_echo(client, EXPIRED_TOKEN_ERROR_STR);
|
||||
tmate_fatal("Expired token");
|
||||
}
|
||||
|
||||
/*
|
||||
* If we are connecting through a symlink, it means that we are a
|
||||
* readonly client.
|
||||
* 1) We mark the client as CLIENT_READONLY on the server
|
||||
* 2) We prevent any input (aside from the window size) to go through
|
||||
* to the server.
|
||||
*/
|
||||
session->readonly = false;
|
||||
if (lstat(socket_path, &fstat) < 0)
|
||||
tmate_fatal("Cannot fstat()");
|
||||
if (S_ISLNK(fstat.st_mode)) {
|
||||
session->readonly = true;
|
||||
argv = argv_ro;
|
||||
argc = 2;
|
||||
}
|
||||
|
||||
if (openpty(&session->pty, &slave_pty, NULL, NULL, NULL) < 0)
|
||||
tmate_fatal("Cannot allocate pty");
|
||||
|
||||
dup2(slave_pty, STDIN_FILENO);
|
||||
dup2(slave_pty, STDOUT_FILENO);
|
||||
dup2(slave_pty, STDERR_FILENO);
|
||||
|
||||
setup_ncurse(slave_pty, "screen-256color");
|
||||
|
||||
tmate_client_pty_init(session);
|
||||
|
||||
/* the unused session->websocket_fd will get closed automatically */
|
||||
close_fds_except((int[]){STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO,
|
||||
session->tmux_socket_fd,
|
||||
ssh_get_fd(session->ssh_client.session),
|
||||
session->pty, log_file ? fileno(log_file) : -1}, 7);
|
||||
get_in_jail();
|
||||
event_reinit(session->ev_base);
|
||||
|
||||
ret = client_main(session->ev_base, argc, argv,
|
||||
CLIENT_UTF8 | CLIENT_256COLOURS, NULL);
|
||||
tmate_flush_pty(session);
|
||||
exit(ret);
|
||||
}
|
||||
|
||||
@ -1,6 +1,8 @@
|
||||
#include "tmate.h"
|
||||
#include <errno.h>
|
||||
|
||||
struct tmate_session _tmate_session, *tmate_session = &_tmate_session;
|
||||
|
||||
static void on_daemon_decoder_read(void *userdata, struct tmate_unpacker *uk)
|
||||
{
|
||||
struct tmate_session *session = userdata;
|
||||
@ -66,7 +68,7 @@ static void on_daemon_encoder_write(void *userdata, struct evbuffer *buffer)
|
||||
}
|
||||
}
|
||||
|
||||
void tmate_daemon_init(struct tmate_session *session)
|
||||
static void tmate_daemon_init(struct tmate_session *session)
|
||||
{
|
||||
struct tmate_ssh_client *client = &session->ssh_client;
|
||||
|
||||
@ -81,3 +83,105 @@ void tmate_daemon_init(struct tmate_session *session)
|
||||
|
||||
tmate_init_websocket(session, NULL);
|
||||
}
|
||||
|
||||
static void handle_sigterm(__unused int sig)
|
||||
{
|
||||
request_server_termination();
|
||||
}
|
||||
|
||||
/* We skip letters that are hard to distinguish when reading */
|
||||
static char rand_tmate_token_digits[] = "abcdefghjkmnpqrstuvwxyz"
|
||||
"ABCDEFGHJKLMNPQRSTUVWXYZ"
|
||||
"23456789";
|
||||
|
||||
#define NUM_DIGITS (sizeof(rand_tmate_token_digits) - 1)
|
||||
|
||||
static char *get_random_token(void)
|
||||
{
|
||||
struct random_stream rs;
|
||||
char *token = xmalloc(TMATE_TOKEN_LEN + 1);
|
||||
int i;
|
||||
unsigned char c;
|
||||
|
||||
random_stream_init(&rs);
|
||||
|
||||
for (i = 0; i < TMATE_TOKEN_LEN; i++) {
|
||||
do {
|
||||
c = *random_stream_get(&rs, 1);
|
||||
} while (c >= NUM_DIGITS);
|
||||
|
||||
token[i] = rand_tmate_token_digits[c];
|
||||
}
|
||||
|
||||
token[i] = 0;
|
||||
|
||||
return token;
|
||||
}
|
||||
|
||||
static void create_session_ro_symlink(struct tmate_session *session)
|
||||
{
|
||||
char *tmp, *token, *session_ro_path;
|
||||
|
||||
#ifdef DEVENV
|
||||
tmp = xstrdup("READONLYTOKENFORDEVENV000");
|
||||
#else
|
||||
tmp = get_random_token();
|
||||
#endif
|
||||
xasprintf(&token, "ro-%s", tmp);
|
||||
free(tmp);
|
||||
|
||||
session->session_token_ro = token;
|
||||
|
||||
xasprintf(&session_ro_path, TMATE_WORKDIR "/sessions/%s",
|
||||
session->session_token_ro);
|
||||
|
||||
unlink(session_ro_path);
|
||||
if (symlink(session->session_token, session_ro_path) < 0)
|
||||
tmate_fatal("Cannot create read-only symlink");
|
||||
free(session_ro_path);
|
||||
}
|
||||
|
||||
void tmate_spawn_daemon(struct tmate_session *session)
|
||||
{
|
||||
struct tmate_ssh_client *client = &session->ssh_client;
|
||||
char *token;
|
||||
|
||||
#ifdef DEVENV
|
||||
token = xstrdup("SUPERSECURETOKENFORDEVENV");
|
||||
#else
|
||||
token = get_random_token();
|
||||
#endif
|
||||
|
||||
set_session_token(session, token);
|
||||
free(token);
|
||||
|
||||
tmate_info("Spawning daemon for %s at %s (%s)",
|
||||
client->username, client->ip_address, client->pubkey);
|
||||
|
||||
session->tmux_socket_fd = server_create_socket();
|
||||
if (session->tmux_socket_fd < 0)
|
||||
tmate_fatal("Cannot create to the tmux socket");
|
||||
|
||||
create_session_ro_symlink(session);
|
||||
|
||||
/*
|
||||
* Needed to initialize the database used in tty-term.c.
|
||||
* We won't have access to it once in the jail.
|
||||
*/
|
||||
setup_ncurse(STDOUT_FILENO, "screen-256color");
|
||||
|
||||
tmate_daemon_init(session);
|
||||
|
||||
close_fds_except((int[]){session->tmux_socket_fd,
|
||||
ssh_get_fd(session->ssh_client.session),
|
||||
log_file ? fileno(log_file) : -1,
|
||||
session->websocket_fd}, 4);
|
||||
|
||||
get_in_jail();
|
||||
event_reinit(session->ev_base);
|
||||
|
||||
tmux_server_init();
|
||||
signal(SIGTERM, handle_sigterm);
|
||||
server_start(session->ev_base, -1, NULL);
|
||||
/* never reached */
|
||||
}
|
||||
|
||||
@ -23,7 +23,7 @@ static void on_websocket_error(struct tmate_session *session, __unused short eve
|
||||
tmate_dump_exec_response(session, 1, "Internal Error\r\n");
|
||||
}
|
||||
|
||||
void tmate_client_exec_init(struct tmate_session *session)
|
||||
static void tmate_client_exec_init(struct tmate_session *session)
|
||||
{
|
||||
struct tmate_ssh_client *client = &session->ssh_client;
|
||||
|
||||
@ -35,3 +35,18 @@ void tmate_client_exec_init(struct tmate_session *session)
|
||||
|
||||
tmate_websocket_exec(session, client->exec_command);
|
||||
}
|
||||
|
||||
void tmate_spawn_exec(struct tmate_session *session)
|
||||
{
|
||||
close_fds_except((int[]){ssh_get_fd(session->ssh_client.session),
|
||||
log_file ? fileno(log_file) : -1,
|
||||
session->websocket_fd}, 3);
|
||||
get_in_jail();
|
||||
event_reinit(session->ev_base);
|
||||
|
||||
tmate_client_exec_init(session);
|
||||
|
||||
if (event_base_dispatch(session->ev_base) < 0)
|
||||
tmate_fatal("Cannot run event loop");
|
||||
exit(0);
|
||||
}
|
||||
|
||||
@ -304,7 +304,11 @@ static void client_bootstrap(struct tmate_session *_session)
|
||||
start_keepalive_timer(client, TMATE_SSH_KEEPALIVE_SEC * 1000);
|
||||
register_on_ssh_read(client);
|
||||
|
||||
tmate_spawn(_session);
|
||||
switch (client->role) {
|
||||
case TMATE_ROLE_DAEMON: tmate_spawn_daemon(_session); break;
|
||||
case TMATE_ROLE_PTY_CLIENT: tmate_spawn_pty_client(_session); break;
|
||||
case TMATE_ROLE_EXEC: tmate_spawn_exec(_session); break;
|
||||
}
|
||||
/* never reached */
|
||||
}
|
||||
|
||||
|
||||
40
tmate.h
40
tmate.h
@ -127,18 +127,16 @@ extern void tmate_dispatch_daemon_message(struct tmate_session *session,
|
||||
#define TMATE_KEYFRAME_INTERVAL_SEC 10
|
||||
#define TMATE_KEYFRAME_MAX_SIZE 1024*1024
|
||||
|
||||
extern void tmate_daemon_init(struct tmate_session *session);
|
||||
extern void tmate_spawn_daemon(struct tmate_session *session);
|
||||
|
||||
/* tmate-ssh-exec.c */
|
||||
|
||||
extern void tmate_spawn_exec(struct tmate_session *session);
|
||||
extern void tmate_dump_exec_response(struct tmate_session *session,
|
||||
int exit_code, const char *message);
|
||||
extern void tmate_client_exec_init(struct tmate_session *session);
|
||||
|
||||
/* tmate-ssh-client-pty.c */
|
||||
|
||||
extern void tmate_client_pty_init(struct tmate_session *session);
|
||||
extern void tmate_flush_pty(struct tmate_session *session);
|
||||
extern void tmate_spawn_pty_client(struct tmate_session *session);
|
||||
extern int tmate_validated_session_token(const char *token);
|
||||
|
||||
/* tmate-ssh-server.c */
|
||||
|
||||
@ -257,9 +255,27 @@ extern struct tmate_session *tmate_session;
|
||||
extern void tmate_get_random_bytes(void *buffer, ssize_t len);
|
||||
extern long tmate_get_random_long(void);
|
||||
extern void request_server_termination(void);
|
||||
extern void tmate_spawn(struct tmate_session *session);
|
||||
extern char *get_socket_path(const char *_token);
|
||||
extern void set_session_token(struct tmate_session *session, const char *token);
|
||||
|
||||
extern void close_fds_except(int *fd_to_preserve, int num_fds);
|
||||
extern void get_in_jail(void);
|
||||
|
||||
/* tmate-rand.c */
|
||||
#define RS_BUF_SIZE 256
|
||||
|
||||
struct random_stream {
|
||||
char bytes[RS_BUF_SIZE];
|
||||
off_t pos;
|
||||
};
|
||||
|
||||
extern void tmate_init_rand(void);
|
||||
extern void tmate_get_random_bytes(void *buffer, ssize_t len);
|
||||
extern long tmate_get_random_long(void);
|
||||
extern void random_stream_init(struct random_stream *rs);
|
||||
extern char *random_stream_get(struct random_stream *rs, size_t count);
|
||||
extern void setup_ncurse(int fd, const char *name);
|
||||
|
||||
/* tmate-websocket.c */
|
||||
|
||||
extern void tmate_websocket_exec(struct tmate_session *session, const char *command);
|
||||
@ -288,4 +304,14 @@ extern void tmate_catch_sigsegv(void);
|
||||
|
||||
extern void tmux_server_init(void);
|
||||
|
||||
/* server.c */
|
||||
extern int server_create_socket(void);
|
||||
|
||||
/* log.c */
|
||||
extern FILE *log_file;
|
||||
|
||||
/* client.c */
|
||||
extern void client_signal(int sig);
|
||||
extern int client_connect(struct event_base *base, const char *path, int start_server);
|
||||
|
||||
#endif
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user