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-rw-r--r--ct_server.c811
1 files changed, 811 insertions, 0 deletions
diff --git a/ct_server.c b/ct_server.c
new file mode 100644
index 0000000..045472e
--- /dev/null
+++ b/ct_server.c
@@ -0,0 +1,811 @@
+/*
+ * curvetun - the cipherspace wormhole creator
+ * Part of the netsniff-ng project
+ * Copyright 2011 Daniel Borkmann <daniel@netsniff-ng.org>,
+ * Subject to the GPL, version 2.
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <pthread.h>
+#include <syslog.h>
+#include <signal.h>
+#include <netdb.h>
+#include <stdint.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <netinet/udp.h>
+#include <sys/poll.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <sys/epoll.h>
+#include <arpa/inet.h>
+#include <linux/if_tun.h>
+
+#include "die.h"
+#include "xutils.h"
+#include "xio.h"
+#include "xmalloc.h"
+#include "curvetun.h"
+#include "curve.h"
+#include "built_in.h"
+#include "ct_usermgmt.h"
+#include "cpusched.h"
+#include "trie.h"
+
+struct parent_info {
+ int efd;
+ int refd;
+ int tunfd;
+ int ipv4;
+ int udp;
+};
+
+struct worker_struct {
+ pthread_t trid;
+ int efd[2];
+ unsigned int cpu;
+ struct parent_info parent;
+ int (*handler)(int fd, const struct worker_struct *ws,
+ char *buff, size_t len);
+ struct curve25519_struct *c;
+};
+
+static struct worker_struct *threadpool = NULL;
+
+static int auth_log = 1;
+
+extern volatile sig_atomic_t sigint;
+
+static int handler_udp_tun_to_net(int fd, const struct worker_struct *ws,
+ char *buff, size_t len) __pure;
+static int handler_udp_net_to_tun(int fd, const struct worker_struct *ws,
+ char *buff, size_t len) __pure;
+static int handler_udp(int fd, const struct worker_struct *ws,
+ char *buff, size_t len) __pure;
+static int handler_tcp_tun_to_net(int fd, const struct worker_struct *ws,
+ char *buff, size_t len) __pure;
+static int handler_tcp_net_to_tun(int fd, const struct worker_struct *ws,
+ char *buff, size_t len) __pure;
+static int handler_tcp(int fd, const struct worker_struct *ws,
+ char *buff, size_t len) __pure;
+ssize_t handler_tcp_read(int fd, char *buff, size_t len);
+static void *worker(void *self) __pure;
+
+static int handler_udp_tun_to_net(int fd, const struct worker_struct *ws,
+ char *buff, size_t len)
+{
+ int dfd, keep = 1;
+ char *cbuff;
+ ssize_t rlen, err, clen;
+ struct ct_proto *hdr;
+ struct curve25519_proto *p;
+ struct sockaddr_storage naddr;
+ socklen_t nlen;
+ size_t off = sizeof(struct ct_proto) + crypto_box_zerobytes;
+
+ if (!buff || len <= off)
+ return 0;
+
+ memset(buff, 0, len);
+ while ((rlen = read(fd, buff + off, len - off)) > 0) {
+ dfd = -1; nlen = 0; p = NULL;
+
+ memset(&naddr, 0, sizeof(naddr));
+
+ hdr = (struct ct_proto *) buff;
+ memset(hdr, 0, sizeof(*hdr));
+ hdr->flags = 0;
+
+ trie_addr_lookup(buff + off, rlen, ws->parent.ipv4, &dfd, &naddr,
+ (size_t *) &nlen);
+ if (unlikely(dfd < 0 || nlen == 0)) {
+ memset(buff, 0, len);
+ continue;
+ }
+
+ err = get_user_by_sockaddr(&naddr, nlen, &p);
+ if (unlikely(err || !p)) {
+ memset(buff, 0, len);
+ continue;
+ }
+
+ clen = curve25519_encode(ws->c, p, (unsigned char *) (buff + off -
+ crypto_box_zerobytes), (rlen +
+ crypto_box_zerobytes), (unsigned char **)
+ &cbuff);
+ if (unlikely(clen <= 0)) {
+ memset(buff, 0, len);
+ continue;
+ }
+
+ hdr->payload = htons((uint16_t) clen);
+
+ set_udp_cork(dfd);
+
+ sendto(dfd, hdr, sizeof(struct ct_proto), 0, (struct sockaddr *)
+ &naddr, nlen);
+ sendto(dfd, cbuff, clen, 0, (struct sockaddr *) &naddr, nlen);
+
+ set_udp_uncork(dfd);
+
+ memset(buff, 0, len);
+ }
+
+ return keep;
+}
+
+static void handler_udp_notify_close(int fd, struct sockaddr_storage *addr)
+{
+ struct ct_proto hdr;
+
+ memset(&hdr, 0, sizeof(hdr));
+ hdr.flags |= PROTO_FLAG_EXIT;
+ hdr.payload = 0;
+
+ sendto(fd, &hdr, sizeof(hdr), 0, (struct sockaddr *) addr,
+ sizeof(*addr));
+}
+
+static int handler_udp_net_to_tun(int fd, const struct worker_struct *ws,
+ char *buff, size_t len)
+{
+ int keep = 1;
+ char *cbuff;
+ ssize_t rlen, err, clen;
+ struct ct_proto *hdr;
+ struct curve25519_proto *p;
+ struct sockaddr_storage naddr;
+ socklen_t nlen = sizeof(naddr);
+
+ if (!buff || !len)
+ return 0;
+
+ memset(&naddr, 0, sizeof(naddr));
+ while ((rlen = recvfrom(fd, buff, len, 0, (struct sockaddr *) &naddr,
+ &nlen)) > 0) {
+ p = NULL;
+
+ hdr = (struct ct_proto *) buff;
+
+ if (unlikely(rlen < sizeof(struct ct_proto)))
+ goto close;
+ if (unlikely(rlen - sizeof(*hdr) != ntohs(hdr->payload)))
+ goto close;
+ if (unlikely(ntohs(hdr->payload) == 0))
+ goto close;
+ if (hdr->flags & PROTO_FLAG_EXIT) {
+close:
+ remove_user_by_sockaddr(&naddr, nlen);
+ trie_addr_remove_addr(&naddr, nlen);
+ handler_udp_notify_close(fd, &naddr);
+
+ return keep;
+ }
+ if (hdr->flags & PROTO_FLAG_INIT) {
+ syslog_maybe(auth_log, LOG_INFO, "Got initial userhash "
+ "from remote end!\n");
+
+ if (unlikely(rlen - sizeof(*hdr) <
+ sizeof(struct username_struct)))
+ goto close;
+
+ err = try_register_user_by_sockaddr(ws->c,
+ buff + sizeof(struct ct_proto),
+ rlen - sizeof(struct ct_proto),
+ &naddr, nlen, auth_log);
+ if (unlikely(err))
+ goto close;
+
+ goto next;
+ }
+
+ err = get_user_by_sockaddr(&naddr, nlen, &p);
+ if (unlikely(err || !p))
+ goto close;
+
+ clen = curve25519_decode(ws->c, p, (unsigned char *) buff +
+ sizeof(struct ct_proto),
+ rlen - sizeof(struct ct_proto),
+ (unsigned char **) &cbuff, NULL);
+ if (unlikely(clen <= 0))
+ goto close;
+
+ cbuff += crypto_box_zerobytes;
+ clen -= crypto_box_zerobytes;
+
+ err = trie_addr_maybe_update(cbuff, clen, ws->parent.ipv4,
+ fd, &naddr, nlen);
+ if (unlikely(err))
+ goto next;
+
+ err = write(ws->parent.tunfd, cbuff, clen);
+next:
+ nlen = sizeof(naddr);
+ memset(&naddr, 0, sizeof(naddr));
+ }
+
+ return keep;
+}
+
+static int handler_udp(int fd, const struct worker_struct *ws,
+ char *buff, size_t len)
+{
+ int ret = 0;
+
+ if (fd == ws->parent.tunfd)
+ ret = handler_udp_tun_to_net(fd, ws, buff, len);
+ else
+ ret = handler_udp_net_to_tun(fd, ws, buff, len);
+
+ return ret;
+}
+
+static int handler_tcp_tun_to_net(int fd, const struct worker_struct *ws,
+ char *buff, size_t len)
+{
+ int dfd, keep = 1;
+ char *cbuff;
+ ssize_t rlen, err, clen;
+ struct ct_proto *hdr;
+ struct curve25519_proto *p;
+ socklen_t nlen;
+ size_t off = sizeof(struct ct_proto) + crypto_box_zerobytes;
+
+ if (!buff || len <= off)
+ return 0;
+
+ memset(buff, 0, len);
+ while ((rlen = read(fd, buff + off, len - off)) > 0) {
+ dfd = -1; p = NULL;
+
+ hdr = (struct ct_proto *) buff;
+ memset(hdr, 0, sizeof(*hdr));
+ hdr->flags = 0;
+
+ trie_addr_lookup(buff + off, rlen, ws->parent.ipv4, &dfd, NULL,
+ (size_t *) &nlen);
+ if (unlikely(dfd < 0)) {
+ memset(buff, 0, len);
+ continue;
+ }
+
+ err = get_user_by_socket(dfd, &p);
+ if (unlikely(err || !p)) {
+ memset(buff, 0, len);
+ continue;
+ }
+
+ clen = curve25519_encode(ws->c, p, (unsigned char *) (buff + off -
+ crypto_box_zerobytes), (rlen +
+ crypto_box_zerobytes), (unsigned char **)
+ &cbuff);
+ if (unlikely(clen <= 0)) {
+ memset(buff, 0, len);
+ continue;
+ }
+
+ hdr->payload = htons((uint16_t) clen);
+
+ set_tcp_cork(dfd);
+
+ write_exact(dfd, hdr, sizeof(struct ct_proto), 0);
+ write_exact(dfd, cbuff, clen, 0);
+
+ set_tcp_uncork(dfd);
+
+ memset(buff, 0, len);
+ }
+
+ return keep;
+}
+
+ssize_t handler_tcp_read(int fd, char *buff, size_t len)
+{
+ ssize_t rlen;
+ struct ct_proto *hdr = (struct ct_proto *) buff;
+
+ if (!buff || !len)
+ return 0;
+
+ /* May exit on EAGAIN if 0 Byte read */
+ rlen = read_exact(fd, buff, sizeof(struct ct_proto), 1);
+ if (rlen < 0)
+ return rlen;
+ if (unlikely(ntohs(hdr->payload) > len - sizeof(struct ct_proto))) {
+ errno = ENOMEM;
+ return 1; /* Force server to close connection */
+ }
+
+ /* May not exit on EAGAIN if 0 Byte read */
+ rlen = read_exact(fd, buff + sizeof(struct ct_proto),
+ ntohs(hdr->payload), 0);
+ if (rlen < 0)
+ return rlen;
+
+ return sizeof(struct ct_proto) + rlen;
+}
+
+static void handler_tcp_notify_close(int fd)
+{
+ struct ct_proto hdr;
+
+ memset(&hdr, 0, sizeof(hdr));
+ hdr.flags |= PROTO_FLAG_EXIT;
+ hdr.payload = 0;
+
+ if (write(fd, &hdr, sizeof(hdr))) { ; }
+}
+
+static int handler_tcp_net_to_tun(int fd, const struct worker_struct *ws,
+ char *buff, size_t len)
+{
+ int keep = 1, count = 0;
+ char *cbuff;
+ ssize_t rlen, err, clen;
+ struct ct_proto *hdr;
+ struct curve25519_proto *p;
+
+ if (!buff || !len)
+ return 0;
+
+ while ((rlen = handler_tcp_read(fd, buff, len)) > 0) {
+ p = NULL;
+
+ hdr = (struct ct_proto *) buff;
+
+ if (unlikely(rlen < sizeof(struct ct_proto)))
+ goto close;
+ if (unlikely(rlen - sizeof(*hdr) != ntohs(hdr->payload)))
+ goto close;
+ if (unlikely(ntohs(hdr->payload) == 0))
+ goto close;
+ if (hdr->flags & PROTO_FLAG_EXIT) {
+close:
+ remove_user_by_socket(fd);
+ trie_addr_remove(fd);
+ handler_tcp_notify_close(fd);
+ rlen = write(ws->parent.efd, &fd, sizeof(fd));
+
+ keep = 0;
+ return keep;
+ }
+ if (hdr->flags & PROTO_FLAG_INIT) {
+ syslog_maybe(auth_log, LOG_INFO, "Got initial userhash "
+ "from remote end!\n");
+
+ if (unlikely(rlen - sizeof(*hdr) <
+ sizeof(struct username_struct)))
+ goto close;
+
+ err = try_register_user_by_socket(ws->c,
+ buff + sizeof(struct ct_proto),
+ rlen - sizeof(struct ct_proto),
+ fd, auth_log);
+ if (unlikely(err))
+ goto close;
+
+ continue;
+ }
+
+ err = get_user_by_socket(fd, &p);
+ if (unlikely(err || !p))
+ continue;
+
+ clen = curve25519_decode(ws->c, p, (unsigned char *) buff +
+ sizeof(struct ct_proto),
+ rlen - sizeof(struct ct_proto),
+ (unsigned char **) &cbuff, NULL);
+ if (unlikely(clen <= 0))
+ continue;
+
+ cbuff += crypto_box_zerobytes;
+ clen -= crypto_box_zerobytes;
+
+ err = trie_addr_maybe_update(cbuff, clen, ws->parent.ipv4,
+ fd, NULL, 0);
+ if (unlikely(err))
+ continue;
+
+ err = write(ws->parent.tunfd, cbuff, clen);
+
+ count++;
+ if (count == 10) {
+ write_exact(ws->efd[1], &fd, sizeof(fd), 1);
+ /* Read later next data and let others process */
+ return keep;
+ }
+ }
+
+ return keep;
+}
+
+static int handler_tcp(int fd, const struct worker_struct *ws,
+ char *buff, size_t len)
+{
+ int ret = 0;
+
+ if (fd == ws->parent.tunfd)
+ ret = handler_tcp_tun_to_net(fd, ws, buff, len);
+ else
+ ret = handler_tcp_net_to_tun(fd, ws, buff, len);
+
+ return ret;
+}
+
+static void *worker(void *self)
+{
+ int fd, old_state;
+ ssize_t ret;
+ size_t blen = TUNBUFF_SIZ; //FIXME
+ const struct worker_struct *ws = self;
+ struct pollfd fds;
+ char *buff;
+
+ fds.fd = ws->efd[0];
+ fds.events = POLLIN;
+
+ curve25519_alloc_or_maybe_die(ws->c);
+
+ buff = xmalloc_aligned(blen, 64);
+
+ syslog(LOG_INFO, "curvetun thread on CPU%u up!\n", ws->cpu);
+
+ pthread_cleanup_push(xfree_func, ws->c);
+ pthread_cleanup_push(curve25519_free, ws->c);
+ pthread_cleanup_push(xfree_func, buff);
+
+ while (likely(!sigint)) {
+ poll(&fds, 1, -1);
+ if ((fds.revents & POLLIN) != POLLIN)
+ continue;
+
+ pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &old_state);
+
+ while ((ret = read_exact(ws->efd[0], &fd, sizeof(fd), 1)) > 0) {
+ if (ret != sizeof(fd)) {
+ sched_yield();
+ continue;
+ }
+
+ ret = ws->handler(fd, ws, buff, blen);
+ if (ret)
+ write_exact(ws->parent.refd, &fd, sizeof(fd), 1);
+ }
+
+ pthread_setcancelstate(old_state, NULL);
+ }
+
+ syslog(LOG_INFO, "curvetun thread on CPU%u down!\n", ws->cpu);
+
+ pthread_cleanup_pop(1);
+ pthread_cleanup_pop(1);
+ pthread_cleanup_pop(1);
+
+ pthread_exit((void *) ((long) ws->cpu));
+}
+
+static void thread_spawn_or_panic(unsigned int cpus, int efd, int refd,
+ int tunfd, int ipv4, int udp)
+{
+ int i, ret;
+ cpu_set_t cpuset;
+ unsigned int threads;
+
+ threads = cpus * THREADS_PER_CPU;
+
+ for (i = 0; i < threads; ++i) {
+ CPU_ZERO(&cpuset);
+ threadpool[i].cpu = i % cpus;
+ CPU_SET(threadpool[i].cpu, &cpuset);
+
+ ret = pipe2(threadpool[i].efd, O_NONBLOCK);
+ if (ret < 0)
+ syslog_panic("Cannot create event socket!\n");
+
+ threadpool[i].c = xmalloc_aligned(sizeof(*threadpool[i].c), 64);
+ threadpool[i].parent.efd = efd;
+ threadpool[i].parent.refd = refd;
+ threadpool[i].parent.tunfd = tunfd;
+ threadpool[i].parent.ipv4 = ipv4;
+ threadpool[i].parent.udp = udp;
+ threadpool[i].handler = udp ? handler_udp : handler_tcp;
+
+ ret = pthread_create(&threadpool[i].trid, NULL,
+ worker, &threadpool[i]);
+ if (ret < 0)
+ syslog_panic("Thread creation failed!\n");
+
+ ret = pthread_setaffinity_np(threadpool[i].trid,
+ sizeof(cpuset), &cpuset);
+ if (ret < 0)
+ syslog_panic("Thread CPU migration failed!\n");
+
+ pthread_detach(threadpool[i].trid);
+ }
+
+ sleep(1);
+}
+
+static void thread_finish(unsigned int cpus)
+{
+ int i;
+ unsigned int threads;
+
+ threads = cpus * THREADS_PER_CPU;
+
+ for (i = 0; i < threads; ++i) {
+ while (pthread_join(threadpool[i].trid, NULL) < 0)
+ ;
+
+ close(threadpool[i].efd[0]);
+ close(threadpool[i].efd[1]);
+ }
+}
+
+int server_main(char *home, char *dev, char *port, int udp, int ipv4, int log)
+{
+ int lfd = -1, kdpfd, nfds, nfd, curfds, efd[2], refd[2], tunfd, i;
+ unsigned int cpus = 0, threads, udp_cpu = 0;
+ ssize_t ret;
+ struct epoll_event *events;
+ struct addrinfo hints, *ahead, *ai;
+
+ auth_log = !!log;
+ openlog("curvetun", LOG_PID | LOG_CONS | LOG_NDELAY, LOG_DAEMON);
+
+ syslog(LOG_INFO, "curvetun server booting!\n");
+ syslog_maybe(!auth_log, LOG_INFO, "curvetun user logging disabled!\n");
+
+ parse_userfile_and_generate_user_store_or_die(home);
+
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = PF_UNSPEC;
+ hints.ai_socktype = udp ? SOCK_DGRAM : SOCK_STREAM;
+ hints.ai_protocol = udp ? IPPROTO_UDP : IPPROTO_TCP;
+ hints.ai_flags = AI_PASSIVE;
+
+ ret = getaddrinfo(NULL, port, &hints, &ahead);
+ if (ret < 0)
+ syslog_panic("Cannot get address info!\n");
+
+ for (ai = ahead; ai != NULL && lfd < 0; ai = ai->ai_next) {
+ lfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
+ if (lfd < 0)
+ continue;
+ if (ai->ai_family == AF_INET6) {
+#ifdef IPV6_V6ONLY
+ ret = set_ipv6_only(lfd);
+ if (ret < 0) {
+ close(lfd);
+ lfd = -1;
+ continue;
+ }
+#else
+ close(lfd);
+ lfd = -1;
+ continue;
+#endif /* IPV6_V6ONLY */
+ }
+
+ set_reuseaddr(lfd);
+ set_mtu_disc_dont(lfd);
+
+ ret = bind(lfd, ai->ai_addr, ai->ai_addrlen);
+ if (ret < 0) {
+ close(lfd);
+ lfd = -1;
+ continue;
+ }
+
+ if (!udp) {
+ ret = listen(lfd, 5);
+ if (ret < 0) {
+ close(lfd);
+ lfd = -1;
+ continue;
+ }
+ }
+
+ if (ipv4 == -1) {
+ ipv4 = (ai->ai_family == AF_INET6 ? 0 :
+ (ai->ai_family == AF_INET ? 1 : -1));
+ }
+
+ syslog_maybe(auth_log, LOG_INFO, "curvetun on IPv%d via %s "
+ "on port %s!\n", ai->ai_family == AF_INET ? 4 : 6,
+ udp ? "UDP" : "TCP", port);
+ syslog_maybe(auth_log, LOG_INFO, "Allowed overlay proto is "
+ "IPv%d!\n", ipv4 ? 4 : 6);
+ }
+
+ freeaddrinfo(ahead);
+
+ if (lfd < 0 || ipv4 < 0)
+ syslog_panic("Cannot create socket!\n");
+
+ tunfd = tun_open_or_die(dev ? dev : DEVNAME_SERVER, IFF_TUN | IFF_NO_PI);
+
+ pipe_or_die(efd, O_NONBLOCK);
+ pipe_or_die(refd, O_NONBLOCK);
+
+ set_nonblocking(lfd);
+
+ events = xzmalloc(MAX_EPOLL_SIZE * sizeof(*events));
+ for (i = 0; i < MAX_EPOLL_SIZE; ++i)
+ events[i].data.fd = -1;
+
+ kdpfd = epoll_create(MAX_EPOLL_SIZE);
+ if (kdpfd < 0)
+ syslog_panic("Cannot create socket!\n");
+
+ set_epoll_descriptor(kdpfd, EPOLL_CTL_ADD, lfd,
+ udp ? EPOLLIN | EPOLLET | EPOLLONESHOT : EPOLLIN);
+ set_epoll_descriptor(kdpfd, EPOLL_CTL_ADD, efd[0], EPOLLIN);
+ set_epoll_descriptor(kdpfd, EPOLL_CTL_ADD, refd[0], EPOLLIN);
+ set_epoll_descriptor(kdpfd, EPOLL_CTL_ADD, tunfd,
+ EPOLLIN | EPOLLET | EPOLLONESHOT);
+ curfds = 4;
+
+ trie_init();
+
+ cpus = get_number_cpus_online();
+ threads = cpus * THREADS_PER_CPU;
+ if (!ispow2(threads))
+ syslog_panic("Thread number not power of two!\n");
+
+ threadpool = xzmalloc(sizeof(*threadpool) * threads);
+ thread_spawn_or_panic(cpus, efd[1], refd[1], tunfd, ipv4, udp);
+
+ init_cpusched(threads);
+
+ register_socket(tunfd);
+ register_socket(lfd);
+
+ syslog(LOG_INFO, "curvetun up and running!\n");
+
+ while (likely(!sigint)) {
+ nfds = epoll_wait(kdpfd, events, curfds, -1);
+ if (nfds < 0) {
+ syslog(LOG_ERR, "epoll_wait error: %s\n",
+ strerror(errno));
+ break;
+ }
+
+ for (i = 0; i < nfds; ++i) {
+ if (unlikely(events[i].data.fd < 0))
+ continue;
+
+ if (events[i].data.fd == lfd && !udp) {
+ int ncpu;
+ char hbuff[256], sbuff[256];
+ struct sockaddr_storage taddr;
+ socklen_t tlen;
+
+ tlen = sizeof(taddr);
+ nfd = accept(lfd, (struct sockaddr *) &taddr,
+ &tlen);
+ if (nfd < 0) {
+ syslog(LOG_ERR, "accept error: %s\n",
+ strerror(errno));
+ continue;
+ }
+
+ if (curfds + 1 > MAX_EPOLL_SIZE) {
+ close(nfd);
+ continue;
+ }
+
+ curfds++;
+
+ ncpu = register_socket(nfd);
+
+ memset(hbuff, 0, sizeof(hbuff));
+ memset(sbuff, 0, sizeof(sbuff));
+ getnameinfo((struct sockaddr *) &taddr, tlen,
+ hbuff, sizeof(hbuff),
+ sbuff, sizeof(sbuff),
+ NI_NUMERICHOST | NI_NUMERICSERV);
+
+ syslog_maybe(auth_log, LOG_INFO, "New connection "
+ "from %s:%s (%d active client connections) - id %d on CPU%d",
+ hbuff, sbuff, curfds-4, nfd, ncpu);
+
+ set_nonblocking(nfd);
+ set_socket_keepalive(nfd);
+ set_tcp_nodelay(nfd);
+ ret = set_epoll_descriptor2(kdpfd, EPOLL_CTL_ADD,
+ nfd, EPOLLIN | EPOLLET | EPOLLONESHOT);
+ if (ret < 0) {
+ close(nfd);
+ curfds--;
+ continue;
+ }
+ } else if (events[i].data.fd == refd[0]) {
+ int fd_one;
+
+ ret = read_exact(refd[0], &fd_one,
+ sizeof(fd_one), 1);
+ if (ret != sizeof(fd_one) || fd_one <= 0)
+ continue;
+
+ ret = set_epoll_descriptor2(kdpfd, EPOLL_CTL_MOD,
+ fd_one, EPOLLIN | EPOLLET | EPOLLONESHOT);
+ if (ret < 0) {
+ close(fd_one);
+ continue;
+ }
+ } else if (events[i].data.fd == efd[0]) {
+ int fd_del, test;
+
+ ret = read_exact(efd[0], &fd_del,
+ sizeof(fd_del), 1);
+ if (ret != sizeof(fd_del) || fd_del <= 0)
+ continue;
+
+ ret = read(fd_del, &test, sizeof(test));
+ if (ret < 0 && errno == EBADF)
+ continue;
+
+ ret = set_epoll_descriptor2(kdpfd, EPOLL_CTL_DEL,
+ fd_del, 0);
+ if (ret < 0) {
+ close(fd_del);
+ continue;
+ }
+
+ close(fd_del);
+ curfds--;
+ unregister_socket(fd_del);
+
+ syslog_maybe(auth_log, LOG_INFO, "Closed connection "
+ "with id %d (%d active client connections remain)\n", fd_del,
+ curfds-4);
+ } else {
+ int cpu, fd_work = events[i].data.fd;
+
+ if (!udp)
+ cpu = socket_to_cpu(fd_work);
+ else
+ udp_cpu = (udp_cpu + 1) & (threads - 1);
+
+ write_exact(threadpool[udp ? udp_cpu : cpu].efd[1],
+ &fd_work, sizeof(fd_work), 1);
+ }
+ }
+ }
+
+ syslog(LOG_INFO, "curvetun prepare shut down!\n");
+
+ close(lfd);
+ close(efd[0]);
+ close(efd[1]);
+ close(refd[0]);
+ close(refd[1]);
+ close(tunfd);
+
+ thread_finish(cpus);
+
+ xfree(threadpool);
+ xfree(events);
+
+ unregister_socket(lfd);
+ unregister_socket(tunfd);
+
+ destroy_cpusched();
+
+ trie_cleanup();
+
+ destroy_user_store();
+
+ syslog(LOG_INFO, "curvetun shut down!\n");
+ closelog();
+
+ return 0;
+}