2 * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file send_common.c Functions used by more than one paraslash sender. */
24 #include "close_on_fork.h"
25 #include "chunk_queue.h"
28 /** Clients will be kicked if there are more than that many bytes pending. */
29 #define MAX_CQ_BYTES 40000
32 * Open a passive socket of given layer4 type.
34 * Set the resulting file descriptor to nonblocking mode and add it to the list
35 * of fds that are being closed in the child process when the server calls
38 * \param l4type The transport-layer protocol.
39 * \param port The port number.
41 * \return The listening fd on success, negative on errors.
43 static int open_sender(unsigned l4type
, int port
)
45 int fd
, ret
= para_listen_simple(l4type
, port
);
50 ret
= mark_fd_nonblocking(fd
);
55 add_close_on_fork_list(fd
);
60 * Shut down a client connected to a paraslash sender.
62 * \param sc The client to shut down.
63 * \param ss The sender whose clients are to be shut down.
65 * Close the file descriptor given by \a sc, remove it from the close-on-fork
66 * list, destroy the chunk queue of this client, delete the client from the
67 * list of connected clients and free the sender_client struct.
69 * \sa shutdown_clients().
71 void shutdown_client(struct sender_client
*sc
, struct sender_status
*ss
)
73 PARA_INFO_LOG("shutting down %s on fd %d\n", sc
->name
, sc
->fd
);
76 del_close_on_fork_list(sc
->fd
);
79 free(sc
->private_data
);
85 * Shut down all clients connected to a paraslash sender.
87 * \param ss The sender whose clients are to be shut down.
89 * This just loops over all connected clients and calls shutdown_client()
92 void shutdown_clients(struct sender_status
*ss
)
94 struct sender_client
*sc
, *tmp
;
95 list_for_each_entry_safe(sc
, tmp
, &ss
->client_list
, node
)
96 shutdown_client(sc
, ss
);
100 * Try to empty the chunk queue for this fd.
102 * \param fd The file descriptor.
103 * \param cq The list of queued chunks.
105 * \return Negative on errors, zero if not everything was sent, one otherwise.
107 int send_queued_chunks(int fd
, struct chunk_queue
*cq
)
109 struct queued_chunk
*qc
;
110 while ((qc
= cq_peek(cq
))) {
115 cq_get(qc
, &buf
, &len
);
116 ret
= write_nonblock(fd
, buf
, len
);
128 * Initialize a struct sender status.
130 * \param ss The struct to initialize.
131 * \param access_arg The array of access arguments given at the command line.
132 * \param num_access_args The number of elements in \a access_arg.
133 * \param port The tcp or dccp port to listen on.
134 * \param max_clients The maximal number of simultaneous connections.
135 * \param default_deny Whether a blacklist should be used for access control.
137 void init_sender_status(struct sender_status
*ss
, char **access_arg
,
138 int num_access_args
, int port
, int max_clients
, int default_deny
)
141 INIT_LIST_HEAD(&ss
->client_list
);
143 acl_init(&ss
->acl
, access_arg
, num_access_args
);
145 ss
->max_clients
= max_clients
;
146 ss
->default_deny
= default_deny
;
150 * Return a string containing the current status of a sender.
152 * \param ss The sender.
153 * \param name Used for printing the header line.
155 * \return The string printed in the "si" command.
157 char *get_sender_info(struct sender_status
*ss
, const char *name
)
159 char *clnts
= NULL
, *ret
;
160 struct sender_client
*sc
, *tmp_sc
;
162 char *acl_contents
= acl_get_contents(&ss
->acl
);
163 list_for_each_entry_safe(sc
, tmp_sc
, &ss
->client_list
, node
) {
164 char *tmp
= make_message("%s%s ", clnts
? clnts
: "", sc
->name
);
172 "\tnumber of connected clients: %d\n"
173 "\tmaximal number of clients: %d%s\n"
174 "\tconnected clients: %s\n"
175 "\taccess %s list: %s\n",
177 (ss
->listen_fd
>= 0)? "on" : "off",
178 stringify_port(ss
->port
, strcmp(name
, "http") ? "dccp" : "tcp"),
181 ss
->max_clients
> 0? "" : " (unlimited)",
182 clnts
? clnts
: "(none)",
183 ss
->default_deny
? "allow" : "deny",
184 acl_contents
? acl_contents
: "(empty)"
192 * Allow connections from the given range of IP addresses.
194 * \param scd Contains the IP and the netmask.
195 * \param ss The sender.
197 * \sa generic_com_deny().
199 void generic_com_allow(struct sender_command_data
*scd
,
200 struct sender_status
*ss
)
202 acl_allow(scd
->host
, scd
->netmask
, &ss
->acl
, ss
->default_deny
);
206 * Deny connections from the given range of IP addresses.
208 * \param scd see \ref generic_com_allow().
209 * \param ss see \ref generic_com_allow().
211 * \sa generic_com_allow().
213 void generic_com_deny(struct sender_command_data
*scd
,
214 struct sender_status
*ss
)
216 acl_deny(scd
->host
, scd
->netmask
, &ss
->acl
, ss
->default_deny
);
220 * Activate a paraslash sender.
222 * \param ss The sender to activate.
223 * \param protocol The symbolic name of the transport-layer protocol.
227 int generic_com_on(struct sender_status
*ss
, unsigned protocol
)
231 if (ss
->listen_fd
>= 0)
233 ret
= open_sender(protocol
, ss
->port
);
241 * Deactivate a paraslash sender.
243 * Shutdown all connected clients and stop listening on the TCP/DCCP socket.
245 * \param ss The sender to deactivate.
247 * \sa \ref del_close_on_fork_list(), shutdown_clients().
249 void generic_com_off(struct sender_status
*ss
)
251 if (ss
->listen_fd
< 0)
253 PARA_NOTICE_LOG("closing port %d\n", ss
->port
);
254 close(ss
->listen_fd
);
255 del_close_on_fork_list(ss
->listen_fd
);
256 shutdown_clients(ss
);
261 * Accept a connection on the socket this server is listening on.
263 * \param ss The sender whose listening fd is ready for reading.
265 * This must be called only if the socket fd of \a ss is ready for reading. It
266 * calls para_accept() to accept the connection and performs the following
267 * actions on the resulting file descriptor \a fd:
269 * - Checks whether the maximal number of connections are exceeded.
270 * - Sets \a fd to nonblocking mode.
271 * - Checks the acl of the sender to find out whether connections
272 * are allowed from the IP of the connecting peer.
273 * - Increases the number of connections for this sender.
274 * - Creates and initializes a new chunk queue for queuing network
275 * packets that can not be sent immediately.
276 * - Allocates a new struct sender_client and fills in its \a fd, \a cq
277 * and \a name members.
278 * - Adds \a fd to the list of connected clients for this sender.
279 * - Adds \a fd to the list of file descriptors that should be closed
280 * in the child process when the server calls fork().
282 * \return A pointer to the allocated sender_client structure on success, \p
285 * \sa \ref para_accept(), \ref mark_fd_nonblocking(), \ref acl_check_access(),
286 * \ref cq_new(), \ref add_close_on_fork_list().
288 struct sender_client
*accept_sender_client(struct sender_status
*ss
, fd_set
*rfds
)
290 struct sender_client
*sc
;
293 if (ss
->listen_fd
< 0)
295 ret
= para_accept(ss
->listen_fd
, rfds
, NULL
, 0, &fd
);
297 PARA_ERROR_LOG("%s\n", para_strerror(-ret
));
300 ret
= -E_MAX_CLIENTS
;
301 if (ss
->max_clients
> 0 && ss
->num_clients
>= ss
->max_clients
)
303 ret
= mark_fd_nonblocking(fd
);
306 ret
= acl_check_access(fd
, &ss
->acl
, ss
->default_deny
);
310 sc
= para_calloc(sizeof(*sc
));
312 sc
->name
= para_strdup(remote_name(fd
));
313 sc
->cq
= cq_new(MAX_CQ_BYTES
);
314 para_list_add(&sc
->node
, &ss
->client_list
);
315 add_close_on_fork_list(fd
);
316 PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", ss
->num_clients
,
320 PARA_WARNING_LOG("%s\n", para_strerror(-ret
));
326 * Get the generic help text.
328 * \return A dynamically allocated string containing the help text for
329 * a paraslash sender.
331 char *generic_sender_help(void)
335 "usage: {allow|deny} IP[/netmask]\n"
336 " where mask defaults to 32\n"
337 "example: allow 192.168.0.1/24\n"
341 static int parse_fec_parms(const char *arg
, struct sender_command_data
*scd
)
344 char *a
= para_strdup(arg
), *b
= a
, *e
= strchr(b
, ':');
345 int ret
= -E_COMMAND_SYNTAX
;
347 /* parse max slice bytes */
351 ret
= para_atoi32(b
, &val
);
354 ret
= -ERRNO_TO_PARA_ERROR(EINVAL
);
355 if (val
< 0 || val
> 65535)
357 scd
->max_slice_bytes
= val
;
358 /* parse data_slices_per_group */
361 ret
= -E_COMMAND_SYNTAX
;
365 ret
= para_atoi32(b
, &val
);
368 ret
= -ERRNO_TO_PARA_ERROR(EINVAL
);
369 if (val
< 0 || val
> 255)
371 scd
->data_slices_per_group
= val
;
372 /* parse slices_per_group */
374 ret
= para_atoi32(b
, &val
);
377 ret
= -ERRNO_TO_PARA_ERROR(EINVAL
);
378 if (val
< 0 || val
< scd
->data_slices_per_group
)
380 scd
->slices_per_group
= val
;
388 * Parse a FEC URL string.
390 * \param arg the URL string to parse.
391 * \param scd The structure containing host, port and the FEC parameters.
395 * A FEC URL consists of an ordinary URL string according to RFC 3986,
396 * optionally followed by a slash and the three FEC parameters slice_size,
397 * data_slices_per_group and slices_per_group. The three FEC parameters are
398 * separated by colons.
400 * \sa \ref parse_url().
402 int parse_fec_url(const char *arg
, struct sender_command_data
*scd
)
405 ssize_t len
= sizeof(scd
->host
);
406 char *a
= para_strdup(arg
), *p
= strchr(a
, '/');
412 ret
= -ERRNO_TO_PARA_ERROR(EINVAL
);
413 if (!parse_url(a
, scd
->host
, len
, &scd
->port
))
416 ret
= parse_fec_parms(p
+ 1, scd
);
419 /* use default fec parameters. */
420 scd
->max_slice_bytes
= 0;
421 scd
->slices_per_group
= 16;
422 scd
->data_slices_per_group
= 14;