/*
- * Copyright (C) 2005-2008 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
/** \file send_common.c Functions used by more than one paraslash sender. */
-#include <dirent.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+#include <regex.h>
+#include <osl.h>
+#include <arpa/inet.h>
+#include <sys/un.h>
+#include <netdb.h>
+
#include "para.h"
#include "error.h"
#include "string.h"
#include "afh.h"
#include "afs.h"
#include "server.h"
+#include "acl.h"
#include "send.h"
#include "close_on_fork.h"
#include "chunk_queue.h"
+#include "sched.h"
#include "vss.h"
+/** Clients will be kicked if there are more than that many bytes pending. */
+#define MAX_CQ_BYTES 40000
/**
* Open a passive socket of given layer4 type.
*
- * Set the resultig file descriptor to nonblocking mode and add it to the list
+ * Set the resulting file descriptor to nonblocking mode and add it to the list
* of fds that are being closed in the child process when the server calls
* fork().
*
*
* \return The listening fd on success, negative on errors.
*/
-int open_sender(unsigned l4type, int port)
+static int open_sender(unsigned l4type, int port)
{
- int fd, ret = para_listen(AF_UNSPEC, l4type, port);
+ int fd, ret = para_listen_simple(l4type, port);
if (ret < 0)
return ret;
}
/**
- * Shut down a connected client.
+ * Shut down a client connected to a paraslash sender.
*
- * \param sc The client to be shut down.
+ * \param sc The client to shut down.
+ * \param ss The sender whose clients are to be shut down.
*
* Close the file descriptor given by \a sc, remove it from the close-on-fork
* list, destroy the chunk queue of this client, delete the client from the
* list of connected clients and free the sender_client struct.
+ *
+ * \sa shutdown_clients().
*/
-void shutdown_client(struct sender_client *sc)
+void shutdown_client(struct sender_client *sc, struct sender_status *ss)
{
PARA_INFO_LOG("shutting down %s on fd %d\n", sc->name, sc->fd);
free(sc->name);
list_del(&sc->node);
free(sc->private_data);
free(sc);
+ ss->num_clients--;
}
/**
- * Write a buffer to a non-blocking file descriptor.
- *
- * \param fd The file descriptor.
- * \param buf the buffer to write.
- * \param len the number of bytes of \a buf.
- * \param max_bytes_per_write Do not write more than that many bytes at once.
+ * Shut down all clients connected to a paraslash sender.
*
- * If \a max_bytes_per_write is non-zero, do not send more than that many bytes
- * per write().
+ * \param ss The sender whose clients are to be shut down.
*
- * EAGAIN is not considered an error condition. For example CCID3 has a
- * sending wait queue which fills up and is emptied asynchronously. The EAGAIN
- * case means that there is currently no space in the wait queue, but this can
- * change at any moment.
- *
- * \return Negative on errors, number of bytes written else.
+ * This just loops over all connected clients and calls shutdown_client()
+ * for each client.
*/
-static int write_nonblock(int fd, const char *buf, size_t len,
- size_t max_bytes_per_write)
+void shutdown_clients(struct sender_status *ss)
{
- size_t written = 0;
- int ret = 0;
-
- while (written < len) {
- size_t num = len - written;
-
- if (max_bytes_per_write && max_bytes_per_write < num)
- num = max_bytes_per_write;
- ret = write(fd, buf + written, num);
- if (ret < 0 && errno == EAGAIN)
- return written;
- if (ret < 0)
- return -ERRNO_TO_PARA_ERROR(errno);
- written += ret;
- }
- return written;
-}
-
-static int queue_chunk_or_shutdown(struct sender_client *sc,
- long unsigned chunk_num, size_t sent)
-{
- int ret = cq_enqueue(sc->cq, chunk_num, sent);
- if (ret < 0)
- shutdown_client(sc);
- return ret;
+ struct sender_client *sc, *tmp;
+ list_for_each_entry_safe(sc, tmp, &ss->client_list, node)
+ shutdown_client(sc, ss);
}
-/* return: negative on errors, zero if not everything was sent, one otherwise */
-static int send_queued_chunks(struct sender_client *sc,
- size_t max_bytes_per_write)
+/**
+ * Try to empty the chunk queue for this fd.
+ *
+ * \param fd The file descriptor.
+ * \param cq The list of queued chunks.
+ *
+ * \return Negative on errors, zero if not everything was sent, one otherwise.
+ */
+int send_queued_chunks(int fd, struct chunk_queue *cq)
{
struct queued_chunk *qc;
- while ((qc = cq_peek(sc->cq))) {
- char *buf;
+ while ((qc = cq_peek(cq))) {
+ const char *buf;
size_t len;
int ret;
+
cq_get(qc, &buf, &len);
- ret = write_nonblock(sc->fd, buf, len, max_bytes_per_write);
+ ret = xwrite(fd, buf, len);
if (ret < 0)
return ret;
- cq_update(sc->cq, ret);
+ cq_update(cq, ret);
if (ret != len)
return 0;
- cq_dequeue(sc->cq);
+ cq_dequeue(cq);
}
return 1;
}
/**
- * Send one chunk of audio data to a connected client.
+ * Initialize a struct sender status.
*
- * \param sc The client.
- * \param max_bytes_per_write Split writes to chunks of at most that many bytes.
- * \param current_chunk The number of the chunk to write.
- * \param buf The data to write.
- * \param len The number of bytes of \a buf.
+ * \param ss The struct to initialize.
+ * \param access_arg The array of access arguments given at the command line.
+ * \param num_access_args The number of elements in \a access_arg.
+ * \param port The tcp or dccp port to listen on.
+ * \param max_clients The maximal number of simultaneous connections.
+ * \param default_deny Whether a blacklist should be used for access control.
+ */
+void init_sender_status(struct sender_status *ss, char **access_arg,
+ int num_access_args, int port, int max_clients, int default_deny)
+{
+ ss->listen_fd = -1;
+ INIT_LIST_HEAD(&ss->client_list);
+ ss->port = port;
+ acl_init(&ss->acl, access_arg, num_access_args);
+ ss->num_clients = 0;
+ ss->max_clients = max_clients;
+ ss->default_deny = default_deny;
+}
+
+/**
+ * Return a string containing the current status of a sender.
+ *
+ * \param ss The sender.
+ * \param name Used for printing the header line.
*
- * On errors, the client is shut down. If only a part of the buffer could be
- * written, the remainder is put into the chunk queue for that client.
+ * \return The string printed in the "si" command.
*/
-void send_chunk(struct sender_client *sc, size_t max_bytes_per_write,
- long unsigned current_chunk, const char *buf, size_t len)
+char *generic_sender_status(struct sender_status *ss, const char *name)
{
- int ret;
+ char *clnts = NULL, *ret;
+ struct sender_client *sc, *tmp_sc;
- if (!sc->header_sent && current_chunk) {
- size_t header_len;
- char *header_buf = vss_get_header(&header_len);
- if (header_buf && header_len > 0) {
- ret = queue_chunk_or_shutdown(sc, -1U, 0);
- if (ret < 0)
- goto out;
- }
- sc->header_sent = 1;
+ char *acl_contents = acl_get_contents(&ss->acl);
+ list_for_each_entry_safe(sc, tmp_sc, &ss->client_list, node) {
+ char *tmp = make_message("%s%s ", clnts? clnts : "", sc->name);
+ free(clnts);
+ clnts = tmp;
}
- ret = send_queued_chunks(sc, max_bytes_per_write);
- if (ret < 0) {
- shutdown_client(sc);
- goto out;
- }
- if (!len)
+ ret = make_message(
+ "status: %s\n"
+ "port: %s\n"
+ "number of connected clients: %d\n"
+ "maximal number of clients: %d%s\n"
+ "connected clients: %s\n"
+ "access %s list: %s\n",
+ (ss->listen_fd >= 0)? "on" : "off",
+ stringify_port(ss->port, strcmp(name, "http") ? "dccp" : "tcp"),
+ ss->num_clients,
+ ss->max_clients,
+ ss->max_clients > 0? "" : " (unlimited)",
+ clnts? clnts : "(none)",
+ ss->default_deny? "allow" : "deny",
+ acl_contents? acl_contents : "(empty)"
+ );
+ free(acl_contents);
+ free(clnts);
+ return ret;
+}
+
+/**
+ * Allow connections from the given range of IP addresses.
+ *
+ * \param scd Contains the IP and the netmask.
+ * \param ss The sender.
+ *
+ * \sa generic_com_deny().
+ */
+void generic_com_allow(struct sender_command_data *scd,
+ struct sender_status *ss)
+{
+ acl_allow(scd->host, scd->netmask, &ss->acl, ss->default_deny);
+}
+
+/**
+ * Deny connections from the given range of IP addresses.
+ *
+ * \param scd see \ref generic_com_allow().
+ * \param ss see \ref generic_com_allow().
+ *
+ * \sa generic_com_allow().
+ */
+void generic_com_deny(struct sender_command_data *scd,
+ struct sender_status *ss)
+{
+ acl_deny(scd->host, scd->netmask, &ss->acl, ss->default_deny);
+}
+
+/**
+ * Activate a paraslash sender.
+ *
+ * \param ss The sender to activate.
+ * \param protocol The symbolic name of the transport-layer protocol.
+ *
+ * \return Standard.
+ */
+int generic_com_on(struct sender_status *ss, unsigned protocol)
+{
+ int ret;
+
+ if (ss->listen_fd >= 0)
+ return 1;
+ ret = open_sender(protocol, ss->port);
+ if (ret < 0)
+ return ret;
+ ss->listen_fd = ret;
+ return 1;
+}
+
+/**
+ * Deactivate a paraslash sender.
+ *
+ * Shutdown all connected clients and stop listening on the TCP/DCCP socket.
+ *
+ * \param ss The sender to deactivate.
+ *
+ * \sa \ref del_close_on_fork_list(), shutdown_clients().
+ */
+void generic_com_off(struct sender_status *ss)
+{
+ if (ss->listen_fd < 0)
+ return;
+ PARA_NOTICE_LOG("closing port %d\n", ss->port);
+ close(ss->listen_fd);
+ del_close_on_fork_list(ss->listen_fd);
+ shutdown_clients(ss);
+ ss->listen_fd = -1;
+}
+
+/**
+ * Accept a connection on the socket this server is listening on.
+ *
+ * \param ss The sender whose listening fd is ready for reading.
+ * \param rfds Passed to para_accept(),
+ *
+ * This must be called only if the socket fd of \a ss is ready for reading. It
+ * calls para_accept() to accept the connection and performs the following
+ * actions on the resulting file descriptor \a fd:
+ *
+ * - Checks whether the maximal number of connections are exceeded.
+ * - Sets \a fd to nonblocking mode.
+ * - Checks the acl of the sender to find out whether connections
+ * are allowed from the IP of the connecting peer.
+ * - Increases the number of connections for this sender.
+ * - Creates and initializes a new chunk queue for queuing network
+ * packets that can not be sent immediately.
+ * - Allocates a new struct sender_client and fills in its \a fd, \a cq
+ * and \a name members.
+ * - Adds \a fd to the list of connected clients for this sender.
+ * - Adds \a fd to the list of file descriptors that should be closed
+ * in the child process when the server calls fork().
+ *
+ * \return A pointer to the allocated sender_client structure on success, \p
+ * NULL on errors.
+ *
+ * \sa \ref para_accept(), \ref mark_fd_nonblocking(), \ref acl_check_access(),
+ * \ref cq_new(), \ref add_close_on_fork_list().
+ */
+struct sender_client *accept_sender_client(struct sender_status *ss, fd_set *rfds)
+{
+ struct sender_client *sc;
+ int fd, ret;
+
+ if (ss->listen_fd < 0)
+ return NULL;
+ ret = para_accept(ss->listen_fd, rfds, NULL, 0, &fd);
+ if (ret < 0)
+ PARA_ERROR_LOG("%s\n", para_strerror(-ret));
+ if (ret <= 0)
+ return NULL;
+ ret = -E_MAX_CLIENTS;
+ if (ss->max_clients > 0 && ss->num_clients >= ss->max_clients)
+ goto err_out;
+ ret = mark_fd_nonblocking(fd);
+ if (ret < 0)
+ goto err_out;
+ ret = acl_check_access(fd, &ss->acl, ss->default_deny);
+ if (ret < 0)
+ goto err_out;
+ ss->num_clients++;
+ sc = para_calloc(sizeof(*sc));
+ sc->fd = fd;
+ sc->name = para_strdup(remote_name(fd));
+ sc->cq = cq_new(MAX_CQ_BYTES);
+ para_list_add(&sc->node, &ss->client_list);
+ add_close_on_fork_list(fd);
+ PARA_INFO_LOG("accepted client #%d: %s (fd %d)\n", ss->num_clients,
+ sc->name, fd);
+ return sc;
+err_out:
+ PARA_WARNING_LOG("%s\n", para_strerror(-ret));
+ close(fd);
+ return NULL;
+}
+
+/**
+ * Get the generic help text.
+ *
+ * \return A dynamically allocated string containing the help text for
+ * a paraslash sender.
+ */
+char *generic_sender_help(void)
+{
+ return make_message(
+ "usage: {on|off}\n"
+ "usage: {allow|deny} IP[/netmask]\n"
+ " where mask defaults to 32\n"
+ "example: allow 192.168.0.1/24\n"
+ );
+}
+
+static int parse_fec_parms(const char *arg, struct sender_command_data *scd)
+{
+ int32_t val;
+ char *a = para_strdup(arg),
+ *b = strchr(a, ':'),
+ *c = strrchr(a, ':');
+ int ret = -E_COMMAND_SYNTAX;
+
+ if (!b || !c)
goto out;
- if (!ret) { /* still data left in the queue */
- ret = queue_chunk_or_shutdown(sc, current_chunk, 0);
+ *b = *c = '\0';
+
+ ret = para_atoi32(a, &val);
+ if (ret < 0)
goto out;
+
+ /* optional max_slice_bytes (0 means "use MTU") */
+ if (b == c) {
+ scd->max_slice_bytes = 0;
+ } else {
+ if (val < 0 || val > 65535)
+ goto fec_einval;
+ scd->max_slice_bytes = val;
+
+ ret = para_atoi32(b + 1, &val);
+ if (ret < 0)
+ goto out;
}
- ret = write_nonblock(sc->fd, buf, len, max_bytes_per_write);
- if (ret < 0) {
- shutdown_client(sc);
+
+ /* k = data_slices_per_group */
+ if (val < 0 || val > 255)
+ goto fec_einval;
+ scd->data_slices_per_group = val;
+
+ /* n = slices_per_group */
+ ret = para_atoi32(c + 1, &val);
+ if (ret < 0)
goto out;
+ if (val < 0 || val < scd->data_slices_per_group)
+ goto fec_einval;
+ scd->slices_per_group = val;
+ ret = 0;
+out:
+ free(a);
+ return ret;
+fec_einval:
+ ret = -ERRNO_TO_PARA_ERROR(EINVAL);
+ goto out;
+}
+
+/**
+ * Parse a FEC URL string.
+ *
+ * \param arg the URL string to parse.
+ * \param scd The structure containing host, port and the FEC parameters.
+ *
+ * \return Standard.
+ *
+ * A FEC URL consists of an ordinary URL string according to RFC 3986,
+ * optionally followed by a slash and the three FEC parameters slice_size,
+ * data_slices_per_group and slices_per_group. The three FEC parameters are
+ * separated by colons.
+ *
+ * \sa \ref parse_url().
+ */
+int parse_fec_url(const char *arg, struct sender_command_data *scd)
+{
+ char *a = para_strdup(arg), *p = strchr(a, '/');
+ int ret = 0;
+
+ /* default fec parameters */
+ scd->max_slice_bytes = 0;
+ scd->data_slices_per_group = 14;
+ scd->slices_per_group = 16;
+
+ if (p) {
+ *p = '\0';
+ ret = parse_fec_parms(p + 1, scd);
+ if (ret < 0)
+ goto out;
}
- if (ret != len)
- ret = queue_chunk_or_shutdown(sc, current_chunk, ret);
+ if (!parse_url(a, scd->host, sizeof(scd->host), &scd->port))
+ ret = -ERRNO_TO_PARA_ERROR(EINVAL);
out:
- if (ret < 0)
- PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
+ free(a);
+ return ret;
}