master.c revision 7753eaa6a4275e074b4ce8428b85d9d04fc67f31
/* Copyright (c) 2002-2008 Dovecot authors, see the included COPYING file */
#include "common.h"
#include "hash.h"
#include "buffer.h"
#include "ioloop.h"
#include "network.h"
#include "fdpass.h"
#include "istream.h"
#include "env-util.h"
#include "write-full.h"
#include "master.h"
#include "client-common.h"
#include <unistd.h>
static int master_fd;
static struct io *io_master;
static struct hash_table *master_requests;
static unsigned int master_tag_counter;
static unsigned int master_pos;
static char master_buf[sizeof(struct master_login_reply)];
static struct client destroyed_client;
static void client_call_master_callback(struct client *client,
enum master_login_status status)
{
master_callback_t *master_callback;
master_callback = client->master_callback;
client->master_tag = 0;
client->master_callback = NULL;
master_callback(client, status);
}
static void request_handle(struct master_login_reply *reply)
{
struct client *client;
if (reply->tag == 0 && !process_per_connection) {
/* this means we have to start listening again.
we've reached maximum number of login processes. */
main_listen_start();
return;
}
client = hash_lookup(master_requests, POINTER_CAST(reply->tag));
if (client == NULL)
i_fatal("Master sent reply with unknown tag %u", reply->tag);
hash_remove(master_requests, POINTER_CAST(reply->tag));
if (client != &destroyed_client) {
client_call_master_callback(client, reply->status);
/* NOTE: client may be destroyed now */
}
}
void master_request_login(struct client *client, master_callback_t *callback,
unsigned int auth_pid, unsigned int auth_id)
{
buffer_t *buf;
struct master_login_request *req;
struct stat st;
const unsigned char *data;
size_t size;
ssize_t ret;
unsigned int cmd_tag_size;
i_assert(auth_pid != 0);
data = i_stream_get_data(client->input, &size);
cmd_tag_size = client->auth_command_tag == NULL ? 0 :
strlen(client->auth_command_tag);
buf = buffer_create_dynamic(pool_datastack_create(),
sizeof(*req) + size + cmd_tag_size);
buffer_write(buf, sizeof(*req), client->auth_command_tag, cmd_tag_size);
buffer_write(buf, sizeof(*req) + cmd_tag_size, data, size);
req = buffer_get_space_unsafe(buf, 0, sizeof(*req));
req->version = MASTER_LOGIN_PROTOCOL_VERSION;
req->tag = ++master_tag_counter;
if (req->tag == 0)
req->tag = ++master_tag_counter;
req->auth_pid = auth_pid;
req->auth_id = auth_id;
req->local_ip = client->local_ip;
req->remote_ip = client->ip;
req->flags = client->master_login_flags;
req->cmd_tag_size = cmd_tag_size;
req->data_size = req->cmd_tag_size + size;
#if (LOGIN_MAX_INBUF_SIZE*2) != MASTER_LOGIN_MAX_DATA_SIZE
# error buffer max sizes unsynced
#endif
i_assert(req->data_size <= LOGIN_MAX_INBUF_SIZE);
if (fstat(client->fd, &st) < 0)
i_fatal("fstat(client) failed: %m");
req->ino = st.st_ino;
ret = fd_send(master_fd, client->fd, buf->data, buf->used);
if (ret < 0)
i_fatal("fd_send(%d) failed: %m", client->fd);
if ((size_t)ret != buf->used) {
i_fatal("fd_send() sent only %d of %d bytes",
(int)ret, (int)buf->used);
}
client->master_tag = req->tag;
client->master_callback = callback;
hash_insert(master_requests, POINTER_CAST(req->tag), client);
}
void master_request_abort(struct client *client)
{
/* we're still going to get the reply from the master, so just
remember that we want to ignore it */
hash_update(master_requests, POINTER_CAST(client->master_tag),
&destroyed_client);
client_call_master_callback(client, FALSE);
}
void master_notify_state_change(enum master_login_state state)
{
struct master_login_request req;
if (io_master == NULL)
return;
memset(&req, 0, sizeof(req));
req.version = MASTER_LOGIN_PROTOCOL_VERSION;
req.tag = state;
req.ino = (ino_t)-1;
/* sending -1 as fd does the notification */
if (fd_send(master_fd, -1, &req, sizeof(req)) != sizeof(req))
i_fatal("fd_send(-1) failed: %m");
}
void master_close(void)
{
if (io_master == NULL)
return;
io_remove(&io_master);
if (close(master_fd) < 0)
i_fatal("close(master) failed: %m");
master_fd = -1;
closing_down = TRUE;
main_listen_stop();
main_unref();
/* may call this function again through main_unref() */
clients_destroy_all();
}
static void master_exec(int fd)
{
static char dovecot[] = "dovecot";
char *argv[] = { dovecot, NULL };
switch (fork()) {
case -1:
i_fatal("fork() failed: %m");
case 0:
if (dup2(fd, 0) < 0)
i_fatal("master_exec: dup2(%d, 0) failed: %m", fd);
(void)close(fd);
if (setsid() < 0)
i_fatal("setsid() failed: %m");
env_put("DOVECOT_INETD=1");
execv(SBINDIR"/dovecot", argv);
i_fatal_status(FATAL_EXEC, "execv(%s) failed: %m",
SBINDIR"/dovecot");
default:
(void)close(fd);
}
}
static void master_read_env(int fd)
{
struct istream *input;
const char *line;
env_clean();
/* read environment variable lines until empty line comes */
input = i_stream_create_fd(fd, 8192, FALSE);
do {
switch (i_stream_read(input)) {
case -1:
i_fatal("EOF while reading environment from master");
case -2:
i_fatal("Too large environment line from master");
}
while ((line = i_stream_next_line(input)) != NULL &&
*line != '\0')
env_put(line);
} while (line == NULL);
i_stream_destroy(&input);
}
int master_connect(const char *group_name)
{
const char *path = PKG_RUNDIR"/master";
int i, fd = -1;
for (i = 0; i < 5 && fd == -1; i++) {
fd = net_connect_unix(path);
if (fd != -1)
break;
if (errno == ECONNREFUSED) {
if (unlink(path) < 0)
i_error("unlink(%s) failed: %m", path);
} else if (errno != ENOENT) {
i_fatal("Can't connect to master UNIX socket %s: %m",
path);
}
/* need to create it */
fd = net_listen_unix(path, 16);
if (fd != -1) {
master_exec(fd);
fd = -1;
} else if (errno != EADDRINUSE) {
i_fatal("Can't create master UNIX socket %s: %m", path);
}
}
if (fd == -1)
i_fatal("Couldn't use/create UNIX socket %s", path);
if (group_name[0] == '\0')
i_fatal("No login group name set");
if (strlen(group_name) >= 256)
i_fatal("Login group name too large: %s", group_name);
/* group_name length is now guaranteed to be in range of 1..255 so we
can send <length byte><name> */
group_name = t_strdup_printf("%c%s", (unsigned char)strlen(group_name),
group_name);
if (write_full(fd, group_name, strlen(group_name)) < 0)
i_fatal("write_full(master_fd) failed: %m");
master_read_env(fd);
return fd;
}
static void master_input(void *context ATTR_UNUSED)
{
int ret;
ret = net_receive(master_fd, master_buf + master_pos,
sizeof(master_buf) - master_pos);
if (ret < 0) {
/* master died, kill all clients logging in */
master_close();
return;
}
master_pos += ret;
if (master_pos < sizeof(master_buf))
return;
/* reply is now read */
request_handle((void *)master_buf);
master_pos = 0;
}
void master_init(int fd)
{
main_ref();
master_fd = fd;
master_requests = hash_create(system_pool, system_pool,
0, NULL, NULL);
master_pos = 0;
io_master = io_add(master_fd, IO_READ, master_input, NULL);
}
void master_deinit(void)
{
hash_destroy(&master_requests);
if (io_master != NULL)
io_remove(&io_master);
}