/* * Ouroboros - Copyright (C) 2016 - 2020 * * Forward loop for broadcast * * Dimitri Staessens <dimitri.staessens@ugent.be> * Sander Vrijders <sander.vrijders@ugent.be> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., http://www.fsf.org/about/contact/. */ #if defined(__linux__) || defined(__CYGWIN__) #define _DEFAULT_SOURCE #else #define _POSIX_C_SOURCE 200112L #endif #include "config.h" #define BROADCAST_MTU 1400 /* FIXME: avoid packet copy. */ #define DT "dt" #define OUROBOROS_PREFIX DT #include <ouroboros/endian.h> #include <ouroboros/dev.h> #include <ouroboros/errno.h> #include <ouroboros/fqueue.h> #include <ouroboros/list.h> #include <ouroboros/logs.h> #include <ouroboros/notifier.h> #include <ouroboros/utils.h> #include "comp.h" #include "connmgr.h" #include "dt.h" #include "ipcp.h" #include <assert.h> #include <stdlib.h> #include <inttypes.h> #include <string.h> #include <pthread.h> struct nb { struct list_head next; int fd; }; struct { struct list_head nbs; size_t nbs_len; pthread_rwlock_t nbs_lock; fset_t * set; pthread_t reader; pthread_t listener; } fwd; static int dt_add_nb(int fd) { struct list_head * p; struct nb * nb; pthread_rwlock_wrlock(&fwd.nbs_lock); list_for_each(p, &fwd.nbs) { struct nb * el = list_entry(p, struct nb, next); if (el->fd == fd) { log_dbg("Already know neighbor."); pthread_rwlock_unlock(&fwd.nbs_lock); return -EPERM; } } nb = malloc(sizeof(*nb)); if (nb == NULL) { pthread_rwlock_unlock(&fwd.nbs_lock); return -ENOMEM; } nb->fd = fd; list_add_tail(&nb->next, p); ++fwd.nbs_len; log_dbg("Neighbor %d added.", fd); pthread_rwlock_unlock(&fwd.nbs_lock); return 0; } static int dt_del_nb(int fd) { struct list_head * p; struct list_head * h; pthread_rwlock_wrlock(&fwd.nbs_lock); list_for_each_safe(p, h, &fwd.nbs) { struct nb * nb = list_entry(p, struct nb, next); if (nb->fd == fd) { list_del(&nb->next); --fwd.nbs_len; pthread_rwlock_unlock(&fwd.nbs_lock); log_dbg("Neighbor %d deleted.", nb->fd); free(nb); return 0; } } pthread_rwlock_unlock(&fwd.nbs_lock); return -EPERM; } static void * dt_conn_handle(void * o) { struct conn conn; (void) o; while (true) { if (connmgr_wait(COMPID_DT, &conn)) { log_err("Failed to get next DT connection."); continue; } /* NOTE: connection acceptance policy could be here. */ notifier_event(NOTIFY_DT_CONN_ADD, &conn); } return 0; } static void dt_packet(uint8_t * buf, size_t len, int in_fd) { struct list_head * p; pthread_rwlock_rdlock(&fwd.nbs_lock); pthread_cleanup_push((void (*))(void *) pthread_rwlock_unlock, &fwd.nbs_lock); list_for_each(p, &fwd.nbs) { struct nb * nb = list_entry(p, struct nb, next); if (nb->fd != in_fd) flow_write(nb->fd, buf, len); /* FIXME: avoid copy. */ } pthread_cleanup_pop(true); } static void * dt_reader(void * o) { fqueue_t * fq; int ret; uint8_t buf[BROADCAST_MTU]; int fd; ssize_t len; (void) o; fq = fqueue_create(); if (fq == NULL) return (void *) -1; pthread_cleanup_push((void (*) (void *)) fqueue_destroy, (void *) fq); while (true) { ret = fevent(fwd.set, fq, NULL); if (ret < 0) { log_warn("Event error: %d.", ret); continue; } while ((fd = fqueue_next(fq)) >= 0) { if (fqueue_type(fq) != FLOW_PKT) continue; /* FIXME: avoid copy. */ len = flow_read(fd, buf, BROADCAST_MTU); if (len < 0) continue; dt_packet(buf, len, fd); } } pthread_cleanup_pop(true); return (void *) 0; } static void handle_event(void * self, int event, const void * o) { /* FIXME: Apply correct QoS on graph */ struct conn * c; (void) self; c = (struct conn *) o; switch (event) { case NOTIFY_DT_CONN_ADD: if (dt_add_nb(c->flow_info.fd)) log_dbg("Failed to add neighbor."); fset_add(fwd.set, c->flow_info.fd); break; case NOTIFY_DT_CONN_DEL: if (dt_del_nb(c->flow_info.fd)) log_dbg("Failed to delete neighbor."); fset_del(fwd.set, c->flow_info.fd); break; default: break; } } int dt_init(void) { struct conn_info info; memset(&info, 0, sizeof(info)); strcpy(info.comp_name, DT); strcpy(info.comp_name, DT_COMP); list_head_init(&fwd.nbs); if (notifier_reg(handle_event, NULL)) goto fail_notifier_reg; if (pthread_rwlock_init(&fwd.nbs_lock, NULL)) goto fail_lock_init; fwd.set = fset_create(); if (fwd.set == NULL) goto fail_fset_create; if (pthread_create(&fwd.reader, NULL, dt_reader, NULL)) goto fail_pthread_create_reader; if (pthread_create(&fwd.listener, NULL, dt_conn_handle, NULL)) goto fail_pthread_create_listener; if (connmgr_comp_init(COMPID_DT, &info)) goto fail_connmgr_comp_init; fwd.nbs_len = 0; return 0; fail_connmgr_comp_init: pthread_cancel(fwd.listener); pthread_join(fwd.listener, NULL); fail_pthread_create_listener: pthread_cancel(fwd.reader); pthread_join(fwd.reader, NULL); fail_pthread_create_reader: fset_destroy(fwd.set); fail_fset_create: pthread_rwlock_destroy(&fwd.nbs_lock); fail_lock_init: notifier_unreg(handle_event); fail_notifier_reg: return -1; } void dt_fini(void) { struct list_head * p; struct list_head * h; notifier_unreg(handle_event); pthread_cancel(fwd.reader); pthread_cancel(fwd.listener); pthread_join(fwd.reader, NULL); pthread_join(fwd.listener, NULL); fset_destroy(fwd.set); pthread_rwlock_wrlock(&fwd.nbs_lock); list_for_each_safe(p, h, &fwd.nbs) { struct nb * n = list_entry(p, struct nb, next); list_del(&n->next); free(n); } pthread_rwlock_unlock(&fwd.nbs_lock); pthread_rwlock_destroy(&fwd.nbs_lock); }