X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=dccp_send.c;h=55f189ad4eb01632dbcd653e104ef7f0cfe54ff8;hp=d2f81dd9168023df27a1fefdb883e3234382c1cc;hb=HEAD;hpb=bae94d3ba972bb91626e5f15e2d5ac44da6b041d diff --git a/dccp_send.c b/dccp_send.c index d2f81dd9..6182c964 100644 --- a/dccp_send.c +++ b/dccp_send.c @@ -1,8 +1,4 @@ -/* - * Copyright (C) 2006-2009 Andre Noll - * - * Licensed under the GPL v2. For licencing details see COPYING. - */ +/* Copyright (C) 2006 Andre Noll , see file COPYING. */ /** \file dccp_send.c Paraslash's dccp sender. */ @@ -11,82 +7,184 @@ * (C) 2005 Ian McDonald */ +#include +#include #include #include -#include -#include +#include +#include +#include +#include +#include "server.lsg.h" #include "para.h" #include "error.h" #include "string.h" #include "afh.h" -#include "afs.h" -#include "server.h" #include "net.h" +#include "server.h" #include "list.h" -#include "vss.h" +#include "sched.h" #include "send.h" +#include "vss.h" #include "fd.h" -#include "close_on_fork.h" -#include "chunk_queue.h" -#include "server.cmdline.h" -#include "acl.h" - -/** Do not write more than that many bytes at once. */ -#define DCCP_MAX_BYTES_PER_WRITE 1024 static struct sender_status dccp_sender_status, *dss = &dccp_sender_status; -static void dccp_pre_select(int *max_fileno, fd_set *rfds, - __a_unused fd_set *wfds) +struct dccp_fec_client { + struct fec_client_parms fcp; + struct fec_client *fc; +}; + +static void dccp_pre_monitor(struct sched *s) { - if (dss->listen_fd >= 0) - para_fd_set(dss->listen_fd, rfds, max_fileno); + unsigned n; + + FOR_EACH_LISTEN_FD(n, dss) + if (dss->listen_fds[n] >= 0) + sched_monitor_readfd(dss->listen_fds[n], s); } -static void dccp_post_select(fd_set *rfds, __a_unused fd_set *wfds) +#ifndef DCCP_SOCKOPT_TX_CCID +#define DCCP_SOCKOPT_TX_CCID 14 /**< Set/get the TX CCID. */ +#endif + +/** + * Query the TX CCID used on the sender-client half connection. + * \param sockfd Server socket descriptor to query (after accept(2)). + * \return CCID number > 0, -1 on error/incompatibility. + * + * NB: This feature is only available on Linux > 2.6.30; on older kernels + * ENOPROTOOPT ("Protocol not available") will be returned. + */ +static int dccp_get_tx_ccid(int sockfd) { - struct sender_client *sc; + int tx_ccid; + socklen_t len = sizeof(tx_ccid); - if (dss->listen_fd < 0 || !FD_ISSET(dss->listen_fd, rfds)) - return; - sc = accept_sender_client(dss); - if (!sc) - return; - /* - * Bypass unused CCID paths: the sender does not receive application data - * from the client; by shutting down this unused communication path we can - * reduce processing costs a bit. See analogous comment in dccp_recv.c. - */ - if (shutdown(sc->fd, SHUT_RD) >= 0) - return; - PARA_WARNING_LOG("%s\n", strerror(errno)); + if (getsockopt(sockfd, SOL_DCCP, + DCCP_SOCKOPT_TX_CCID, &tx_ccid, &len) < 0) { + PARA_WARNING_LOG("DCCP_SOCKOPT_TX_CCID: %s\n", strerror(errno)); + return -1; + } + return tx_ccid; +} + +static void dccp_shutdown_client(struct sender_client *sc) +{ + struct dccp_fec_client *dfc = sc->private_data; + + vss_del_fec_client(dfc->fc); shutdown_client(sc, dss); } -static void dccp_send(long unsigned current_chunk, - __a_unused long unsigned chunks_sent, const char *buf, - size_t len, const char *header_buf, size_t header_len) +static void dccp_shutdown_clients(void) { struct sender_client *sc, *tmp; list_for_each_entry_safe(sc, tmp, &dss->client_list, node) - send_chunk(sc, dss, DCCP_MAX_BYTES_PER_WRITE, current_chunk, buf, - len, header_buf, header_len); + dccp_shutdown_client(sc); } -static void dccp_shutdown_clients(void) +static void dccp_shutdown(void) { - shutdown_clients(dss); + dccp_shutdown_clients(); + generic_acl_deplete(&dss->acl); + free_sender_status(dss); +} + +#ifndef DCCP_SOCKOPT_GET_CUR_MPS +#define DCCP_SOCKOPT_GET_CUR_MPS 5 /**< Max packet size, RFC 4340, 14. */ +#endif + +/** Estimated worst-case length of a DCCP header including options. */ +#define DCCP_MAX_HEADER 128 + +/** * Obtain current MPS according to RFC 4340, sec. 14. */ +static int dccp_init_fec(struct sender_client *sc) +{ + int mps, ret; + socklen_t ml = sizeof(mps); + uint32_t mss; /* max slize size */ + + /* If call fails, return some sensible minimum value */ + ret = getsockopt(sc->fd, SOL_DCCP, DCCP_SOCKOPT_GET_CUR_MPS, &mps, &ml); + if (ret < 0) { + PARA_NOTICE_LOG("can not determine MPS: %s\n", strerror(errno)); + mps = generic_max_transport_msg_size(sc->fd) - DCCP_MAX_HEADER; + } + PARA_INFO_LOG("current MPS = %d bytes\n", mps); + assert(mps > 0); + mss = OPT_UINT32_VAL(DCCP_MAX_SLICE_SIZE); + if (mss > 0 && mss <= INT_MAX) + mps = PARA_MIN(mps, (int)mss); + return mps; +} + +static void dccp_send_fec(struct sender_client *sc, char *buf, size_t len) +{ + int ret = xwrite(sc->fd, buf, len); + + if (ret < 0) + dccp_shutdown_client(sc); +} + +static void dccp_post_monitor(__a_unused struct sched *s) +{ + struct sender_client *sc; + struct dccp_fec_client *dfc; + int tx_ccid; + uint32_t k, n; + + sc = accept_sender_client(dss); + if (!sc) + return; + + /* If CCID identifiable, present client as #~ */ + tx_ccid = dccp_get_tx_ccid(sc->fd); + if (tx_ccid != -1) { + char *tmp = make_message("%s~%d", sc->name, tx_ccid); + + free(sc->name); + sc->name = tmp; + } + /* + * Bypass unused CCID paths: the sender does not receive application data + * from the client; by shutting down this unused communication path we can + * reduce processing costs a bit. See analogous comment in \ref dccp_recv.c. + */ + if (shutdown(sc->fd, SHUT_RD) < 0) { + PARA_WARNING_LOG("%s\n", strerror(errno)); + shutdown_client(sc, dss); + return; + } + dfc = zalloc(sizeof(*dfc)); + sc->private_data = dfc; + k = OPT_UINT32_VAL(DCCP_DATA_SLICES_PER_GROUP); + n = OPT_UINT32_VAL(DCCP_SLICES_PER_GROUP); + if (k == 0 || n == 0 || k >= n) { + PARA_WARNING_LOG("invalid FEC parameters, using defaults\n"); + dfc->fcp.data_slices_per_group = 3; + dfc->fcp.slices_per_group = 4; + } else { + dfc->fcp.data_slices_per_group = k; + dfc->fcp.slices_per_group = n; + } + dfc->fcp.init_fec = dccp_init_fec; + dfc->fcp.send_fec = dccp_send_fec; + dfc->fcp.need_periodic_header = false; + dfc->fc = vss_add_fec_client(sc, &dfc->fcp); } static int dccp_com_on(__a_unused struct sender_command_data *scd) { - return generic_com_on(dss, IPPROTO_DCCP); + generic_com_on(dss, IPPROTO_DCCP); + return 1; } static int dccp_com_off(__a_unused struct sender_command_data *scd) { + dccp_shutdown_clients(); generic_com_off(dss); return 1; } @@ -104,40 +202,72 @@ static int dccp_com_allow(struct sender_command_data *scd) return 1; } -static char *dccp_info(void) +/** + * Return list of available CCIDs or warning, in static buffer. + */ +static const char *dccp_list_available_ccids(void) { - return get_sender_info(dss, "dccp"); + /* Worst case length: n * 3 digits + n-1 spaces + '\0' */ + static char list[DCCP_MAX_HOST_CCIDS * 4]; + uint8_t *ccids; + int i, len, nccids; + + nccids = dccp_available_ccids(&ccids); + if (nccids < 0) { + snprintf(list, sizeof(list), "Unable to query available CCIDs"); + } else { + for (i = len = 0; i < nccids; i++) + len += snprintf(list + len, sizeof(list) - len, + "%s%d", i ? " " : "", ccids[i]); + } + return list; } -/** - * The init function of the dccp sender. - * - * \param s pointer to the dccp sender struct. - * - * It initializes all function pointers of \a s and starts - * listening on the given port. +static char *dccp_status(void) +{ + char *status = generic_sender_status(dss, "dccp"); + char *result = make_message("%ssupported ccids: %s\n", status, + dccp_list_available_ccids()); + free(status); + return result; +} + +/* + * Initialize the client list and the access control list and listen on the + * dccp port. */ -void dccp_send_init(struct sender *s) +static void dccp_send_init(void) { - int ret; - - s->info = dccp_info; - s->send = dccp_send; - s->pre_select = dccp_pre_select; - s->post_select = dccp_post_select; - s->shutdown_clients = dccp_shutdown_clients; - s->help = generic_sender_help; - s->client_cmds[SENDER_ON] = dccp_com_on; - s->client_cmds[SENDER_OFF] = dccp_com_off; - s->client_cmds[SENDER_DENY] = dccp_com_deny; - s->client_cmds[SENDER_ALLOW] = dccp_com_allow; - s->client_cmds[SENDER_ADD] = NULL; - s->client_cmds[SENDER_DELETE] = NULL; - - init_sender_status(dss, conf.dccp_access_arg, conf.dccp_access_given, - conf.dccp_port_arg, conf.dccp_max_clients_arg, - conf.dccp_default_deny_given); - ret = generic_com_on(dss, IPPROTO_DCCP); - if (ret < 0) - PARA_ERROR_LOG("%s\n", para_strerror(-ret)); + init_sender_status(dss, OPT_RESULT(DCCP_ACCESS), + OPT_RESULT(DCCP_LISTEN_ADDRESS), + OPT_UINT32_VAL(DCCP_PORT), OPT_UINT32_VAL(DCCP_MAX_CLIENTS), + OPT_GIVEN(DCCP_DEFAULT_DENY)); + if (OPT_GIVEN(DCCP_NO_AUTOSTART)) + return; + generic_com_on(dss, IPPROTO_DCCP); } + +/** + * The DCCP sender. + * + * This sender offers congestion control not available in plain TCP. Most + * methods of the sender structure are implemented as simple wrappers for the + * generic functions defined in \ref send_common.c. Like UDP streams, DCCP + * streams are sent FEC-encoded. + */ +const struct sender dccp_sender = { + .name = "dccp", + .init = dccp_send_init, + .shutdown = dccp_shutdown, + .pre_monitor = dccp_pre_monitor, + .post_monitor = dccp_post_monitor, + .shutdown_clients = dccp_shutdown_clients, + .client_cmds = { + [SENDER_on] = dccp_com_on, + [SENDER_off] = dccp_com_off, + [SENDER_deny] = dccp_com_deny, + [SENDER_allow] = dccp_com_allow, + }, + .help = generic_sender_help, + .status = dccp_status, +};