/* * * Copyright 2015, Google Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following disclaimer * in the documentation and/or other materials provided with the * distribution. * * Neither the name of Google Inc. nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ /* FIXME: "posix" files shouldn't be depending on _GNU_SOURCE */ #ifndef _GNU_SOURCE #define _GNU_SOURCE #endif #include #ifdef GPR_POSIX_SOCKET #include "src/core/lib/iomgr/tcp_server.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "src/core/lib/iomgr/resolve_address.h" #include "src/core/lib/iomgr/sockaddr_utils.h" #include "src/core/lib/iomgr/socket_utils_posix.h" #include "src/core/lib/iomgr/tcp_posix.h" #include "src/core/lib/iomgr/unix_sockets_posix.h" #include "src/core/lib/support/string.h" #define MIN_SAFE_ACCEPT_QUEUE_SIZE 100 static gpr_once s_init_max_accept_queue_size; static int s_max_accept_queue_size; /* one listening port */ typedef struct grpc_tcp_listener grpc_tcp_listener; struct grpc_tcp_listener { int fd; grpc_fd *emfd; grpc_tcp_server *server; union { uint8_t untyped[GRPC_MAX_SOCKADDR_SIZE]; struct sockaddr sockaddr; } addr; size_t addr_len; int port; unsigned port_index; unsigned fd_index; grpc_closure read_closure; grpc_closure destroyed_closure; struct grpc_tcp_listener *next; /* When we add a listener, more than one can be created, mainly because of IPv6. A sibling will still be in the normal list, but will be flagged as such. Any action, such as ref or unref, will affect all of the siblings in the list. */ struct grpc_tcp_listener *sibling; int is_sibling; }; /* the overall server */ struct grpc_tcp_server { gpr_refcount refs; /* Called whenever accept() succeeds on a server port. */ grpc_tcp_server_cb on_accept_cb; void *on_accept_cb_arg; gpr_mu mu; /* active port count: how many ports are actually still listening */ size_t active_ports; /* destroyed port count: how many ports are completely destroyed */ size_t destroyed_ports; /* is this server shutting down? */ bool shutdown; /* use SO_REUSEPORT */ bool so_reuseport; /* linked list of server ports */ grpc_tcp_listener *head; grpc_tcp_listener *tail; unsigned nports; /* List of closures passed to shutdown_starting_add(). */ grpc_closure_list shutdown_starting; /* shutdown callback */ grpc_closure *shutdown_complete; /* all pollsets interested in new connections */ grpc_pollset **pollsets; /* number of pollsets in the pollsets array */ size_t pollset_count; /* next pollset to assign a channel to */ gpr_atm next_pollset_to_assign; }; static gpr_once check_init = GPR_ONCE_INIT; static bool has_so_reuseport; static void init(void) { int s = socket(AF_INET, SOCK_STREAM, 0); if (s >= 0) { has_so_reuseport = GRPC_LOG_IF_ERROR("check for SO_REUSEPORT", grpc_set_socket_reuse_port(s, 1)); close(s); } } grpc_error *grpc_tcp_server_create(grpc_closure *shutdown_complete, const grpc_channel_args *args, grpc_tcp_server **server) { gpr_once_init(&check_init, init); grpc_tcp_server *s = gpr_malloc(sizeof(grpc_tcp_server)); s->so_reuseport = has_so_reuseport; for (size_t i = 0; i < (args == NULL ? 0 : args->num_args); i++) { if (0 == strcmp(GRPC_ARG_ALLOW_REUSEPORT, args->args[i].key)) { if (args->args[i].type == GRPC_ARG_INTEGER) { s->so_reuseport = has_so_reuseport && (args->args[i].value.integer != 0); } else { gpr_free(s); return GRPC_ERROR_CREATE(GRPC_ARG_ALLOW_REUSEPORT " must be an integer"); } } } gpr_ref_init(&s->refs, 1); gpr_mu_init(&s->mu); s->active_ports = 0; s->destroyed_ports = 0; s->shutdown = false; s->shutdown_starting.head = NULL; s->shutdown_starting.tail = NULL; s->shutdown_complete = shutdown_complete; s->on_accept_cb = NULL; s->on_accept_cb_arg = NULL; s->head = NULL; s->tail = NULL; s->nports = 0; gpr_atm_no_barrier_store(&s->next_pollset_to_assign, 0); *server = s; return GRPC_ERROR_NONE; } static void finish_shutdown(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) { if (s->shutdown_complete != NULL) { grpc_exec_ctx_sched(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE, NULL); } gpr_mu_destroy(&s->mu); while (s->head) { grpc_tcp_listener *sp = s->head; s->head = sp->next; gpr_free(sp); } gpr_free(s); } static void destroyed_port(grpc_exec_ctx *exec_ctx, void *server, grpc_error *error) { grpc_tcp_server *s = server; gpr_mu_lock(&s->mu); s->destroyed_ports++; if (s->destroyed_ports == s->nports) { gpr_mu_unlock(&s->mu); finish_shutdown(exec_ctx, s); } else { GPR_ASSERT(s->destroyed_ports < s->nports); gpr_mu_unlock(&s->mu); } } /* called when all listening endpoints have been shutdown, so no further events will be received on them - at this point it's safe to destroy things */ static void deactivated_all_ports(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) { /* delete ALL the things */ gpr_mu_lock(&s->mu); if (!s->shutdown) { gpr_mu_unlock(&s->mu); return; } if (s->head) { grpc_tcp_listener *sp; for (sp = s->head; sp; sp = sp->next) { grpc_unlink_if_unix_domain_socket(&sp->addr.sockaddr); sp->destroyed_closure.cb = destroyed_port; sp->destroyed_closure.cb_arg = s; grpc_fd_orphan(exec_ctx, sp->emfd, &sp->destroyed_closure, NULL, "tcp_listener_shutdown"); } gpr_mu_unlock(&s->mu); } else { gpr_mu_unlock(&s->mu); finish_shutdown(exec_ctx, s); } } static void tcp_server_destroy(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) { gpr_mu_lock(&s->mu); GPR_ASSERT(!s->shutdown); s->shutdown = true; /* shutdown all fd's */ if (s->active_ports) { grpc_tcp_listener *sp; for (sp = s->head; sp; sp = sp->next) { grpc_fd_shutdown(exec_ctx, sp->emfd); } gpr_mu_unlock(&s->mu); } else { gpr_mu_unlock(&s->mu); deactivated_all_ports(exec_ctx, s); } } /* get max listen queue size on linux */ static void init_max_accept_queue_size(void) { int n = SOMAXCONN; char buf[64]; FILE *fp = fopen("/proc/sys/net/core/somaxconn", "r"); if (fp == NULL) { /* 2.4 kernel. */ s_max_accept_queue_size = SOMAXCONN; return; } if (fgets(buf, sizeof buf, fp)) { char *end; long i = strtol(buf, &end, 10); if (i > 0 && i <= INT_MAX && end && *end == 0) { n = (int)i; } } fclose(fp); s_max_accept_queue_size = n; if (s_max_accept_queue_size < MIN_SAFE_ACCEPT_QUEUE_SIZE) { gpr_log(GPR_INFO, "Suspiciously small accept queue (%d) will probably lead to " "connection drops", s_max_accept_queue_size); } } static int get_max_accept_queue_size(void) { gpr_once_init(&s_init_max_accept_queue_size, init_max_accept_queue_size); return s_max_accept_queue_size; } /* Prepare a recently-created socket for listening. */ static grpc_error *prepare_socket(int fd, const struct sockaddr *addr, size_t addr_len, bool so_reuseport, int *port) { struct sockaddr_storage sockname_temp; socklen_t sockname_len; grpc_error *err = GRPC_ERROR_NONE; GPR_ASSERT(fd >= 0); if (so_reuseport) { err = grpc_set_socket_reuse_port(fd, 1); if (err != GRPC_ERROR_NONE) goto error; } err = grpc_set_socket_nonblocking(fd, 1); if (err != GRPC_ERROR_NONE) goto error; err = grpc_set_socket_cloexec(fd, 1); if (err != GRPC_ERROR_NONE) goto error; if (!grpc_is_unix_socket(addr)) { err = grpc_set_socket_low_latency(fd, 1); if (err != GRPC_ERROR_NONE) goto error; err = grpc_set_socket_reuse_addr(fd, 1); if (err != GRPC_ERROR_NONE) goto error; } err = grpc_set_socket_no_sigpipe_if_possible(fd); if (err != GRPC_ERROR_NONE) goto error; GPR_ASSERT(addr_len < ~(socklen_t)0); if (bind(fd, addr, (socklen_t)addr_len) < 0) { err = GRPC_OS_ERROR(errno, "bind"); goto error; } if (listen(fd, get_max_accept_queue_size()) < 0) { err = GRPC_OS_ERROR(errno, "listen"); goto error; } sockname_len = sizeof(sockname_temp); if (getsockname(fd, (struct sockaddr *)&sockname_temp, &sockname_len) < 0) { err = GRPC_OS_ERROR(errno, "getsockname"); goto error; } *port = grpc_sockaddr_get_port((struct sockaddr *)&sockname_temp); return GRPC_ERROR_NONE; error: GPR_ASSERT(err != GRPC_ERROR_NONE); if (fd >= 0) { close(fd); } grpc_error *ret = grpc_error_set_int( GRPC_ERROR_CREATE_REFERENCING("Unable to configure socket", &err, 1), GRPC_ERROR_INT_FD, fd); GRPC_ERROR_UNREF(err); return ret; } /* event manager callback when reads are ready */ static void on_read(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *err) { grpc_tcp_listener *sp = arg; grpc_tcp_server_acceptor acceptor = {sp->server, sp->port_index, sp->fd_index}; grpc_pollset *read_notifier_pollset = NULL; grpc_fd *fdobj; if (err != GRPC_ERROR_NONE) { goto error; } read_notifier_pollset = sp->server->pollsets[(size_t)gpr_atm_no_barrier_fetch_add( &sp->server->next_pollset_to_assign, 1) % sp->server->pollset_count]; /* loop until accept4 returns EAGAIN, and then re-arm notification */ for (;;) { struct sockaddr_storage addr; socklen_t addrlen = sizeof(addr); char *addr_str; char *name; /* Note: If we ever decide to return this address to the user, remember to strip off the ::ffff:0.0.0.0/96 prefix first. */ int fd = grpc_accept4(sp->fd, (struct sockaddr *)&addr, &addrlen, 1, 1); if (fd < 0) { switch (errno) { case EINTR: continue; case EAGAIN: grpc_fd_notify_on_read(exec_ctx, sp->emfd, &sp->read_closure); return; default: gpr_log(GPR_ERROR, "Failed accept4: %s", strerror(errno)); goto error; } } grpc_set_socket_no_sigpipe_if_possible(fd); addr_str = grpc_sockaddr_to_uri((struct sockaddr *)&addr); gpr_asprintf(&name, "tcp-server-connection:%s", addr_str); if (grpc_tcp_trace) { gpr_log(GPR_DEBUG, "SERVER_CONNECT: incoming connection: %s", addr_str); } fdobj = grpc_fd_create(fd, name); if (read_notifier_pollset == NULL) { gpr_log(GPR_ERROR, "Read notifier pollset is not set on the fd"); goto error; } grpc_pollset_add_fd(exec_ctx, read_notifier_pollset, fdobj); sp->server->on_accept_cb( exec_ctx, sp->server->on_accept_cb_arg, grpc_tcp_create(fdobj, GRPC_TCP_DEFAULT_READ_SLICE_SIZE, addr_str), read_notifier_pollset, &acceptor); gpr_free(name); gpr_free(addr_str); } GPR_UNREACHABLE_CODE(return ); error: gpr_mu_lock(&sp->server->mu); if (0 == --sp->server->active_ports) { gpr_mu_unlock(&sp->server->mu); deactivated_all_ports(exec_ctx, sp->server); } else { gpr_mu_unlock(&sp->server->mu); } } static grpc_error *add_socket_to_server(grpc_tcp_server *s, int fd, const struct sockaddr *addr, size_t addr_len, unsigned port_index, unsigned fd_index, grpc_tcp_listener **listener) { grpc_tcp_listener *sp = NULL; int port = -1; char *addr_str; char *name; grpc_error *err = prepare_socket(fd, addr, addr_len, s->so_reuseport, &port); if (err == GRPC_ERROR_NONE) { GPR_ASSERT(port > 0); grpc_sockaddr_to_string(&addr_str, (struct sockaddr *)&addr, 1); gpr_asprintf(&name, "tcp-server-listener:%s", addr_str); gpr_mu_lock(&s->mu); s->nports++; GPR_ASSERT(!s->on_accept_cb && "must add ports before starting server"); sp = gpr_malloc(sizeof(grpc_tcp_listener)); sp->next = NULL; if (s->head == NULL) { s->head = sp; } else { s->tail->next = sp; } s->tail = sp; sp->server = s; sp->fd = fd; sp->emfd = grpc_fd_create(fd, name); memcpy(sp->addr.untyped, addr, addr_len); sp->addr_len = addr_len; sp->port = port; sp->port_index = port_index; sp->fd_index = fd_index; sp->is_sibling = 0; sp->sibling = NULL; GPR_ASSERT(sp->emfd); gpr_mu_unlock(&s->mu); gpr_free(addr_str); gpr_free(name); } *listener = sp; return err; } static grpc_error *clone_port(grpc_tcp_listener *listener, unsigned count) { grpc_tcp_listener *sp = NULL; char *addr_str; char *name; grpc_error *err; for (grpc_tcp_listener *l = listener->next; l && l->is_sibling; l = l->next) { l->fd_index += count; } for (unsigned i = 0; i < count; i++) { int fd, port; grpc_dualstack_mode dsmode; err = grpc_create_dualstack_socket(&listener->addr.sockaddr, SOCK_STREAM, 0, &dsmode, &fd); if (err != GRPC_ERROR_NONE) return err; err = prepare_socket(fd, &listener->addr.sockaddr, listener->addr_len, true, &port); if (err != GRPC_ERROR_NONE) return err; listener->server->nports++; grpc_sockaddr_to_string(&addr_str, &listener->addr.sockaddr, 1); gpr_asprintf(&name, "tcp-server-listener:%s/clone-%d", addr_str, i); sp = gpr_malloc(sizeof(grpc_tcp_listener)); sp->next = listener->next; listener->next = sp; sp->server = listener->server; sp->fd = fd; sp->emfd = grpc_fd_create(fd, name); memcpy(sp->addr.untyped, listener->addr.untyped, listener->addr_len); sp->addr_len = listener->addr_len; sp->port = port; sp->port_index = listener->port_index; sp->fd_index = listener->fd_index + count - i; sp->is_sibling = 1; sp->sibling = listener->is_sibling ? listener->sibling : listener; GPR_ASSERT(sp->emfd); while (listener->server->tail->next != NULL) { listener->server->tail = listener->server->tail->next; } gpr_free(addr_str); gpr_free(name); } return GRPC_ERROR_NONE; } grpc_error *grpc_tcp_server_add_port(grpc_tcp_server *s, const void *addr, size_t addr_len, int *out_port) { grpc_tcp_listener *sp; grpc_tcp_listener *sp2 = NULL; int fd; grpc_dualstack_mode dsmode; struct sockaddr_in6 addr6_v4mapped; struct sockaddr_in wild4; struct sockaddr_in6 wild6; struct sockaddr_in addr4_copy; struct sockaddr *allocated_addr = NULL; struct sockaddr_storage sockname_temp; socklen_t sockname_len; int port; unsigned port_index = 0; unsigned fd_index = 0; grpc_error *errs[2] = {GRPC_ERROR_NONE, GRPC_ERROR_NONE}; if (s->tail != NULL) { port_index = s->tail->port_index + 1; } grpc_unlink_if_unix_domain_socket((struct sockaddr *)addr); /* Check if this is a wildcard port, and if so, try to keep the port the same as some previously created listener. */ if (grpc_sockaddr_get_port(addr) == 0) { for (sp = s->head; sp; sp = sp->next) { sockname_len = sizeof(sockname_temp); if (0 == getsockname(sp->fd, (struct sockaddr *)&sockname_temp, &sockname_len)) { port = grpc_sockaddr_get_port((struct sockaddr *)&sockname_temp); if (port > 0) { allocated_addr = gpr_malloc(addr_len); memcpy(allocated_addr, addr, addr_len); grpc_sockaddr_set_port(allocated_addr, port); addr = allocated_addr; break; } } } } sp = NULL; if (grpc_sockaddr_to_v4mapped(addr, &addr6_v4mapped)) { addr = (const struct sockaddr *)&addr6_v4mapped; addr_len = sizeof(addr6_v4mapped); } /* Treat :: or 0.0.0.0 as a family-agnostic wildcard. */ if (grpc_sockaddr_is_wildcard(addr, &port)) { grpc_sockaddr_make_wildcards(port, &wild4, &wild6); /* Try listening on IPv6 first. */ addr = (struct sockaddr *)&wild6; addr_len = sizeof(wild6); errs[0] = grpc_create_dualstack_socket(addr, SOCK_STREAM, 0, &dsmode, &fd); if (errs[0] == GRPC_ERROR_NONE) { errs[0] = add_socket_to_server(s, fd, addr, addr_len, port_index, fd_index, &sp); if (fd >= 0 && dsmode == GRPC_DSMODE_DUALSTACK) { goto done; } if (sp != NULL) { ++fd_index; } /* If we didn't get a dualstack socket, also listen on 0.0.0.0. */ if (port == 0 && sp != NULL) { grpc_sockaddr_set_port((struct sockaddr *)&wild4, sp->port); } } addr = (struct sockaddr *)&wild4; addr_len = sizeof(wild4); } errs[1] = grpc_create_dualstack_socket(addr, SOCK_STREAM, 0, &dsmode, &fd); if (errs[1] == GRPC_ERROR_NONE) { if (dsmode == GRPC_DSMODE_IPV4 && grpc_sockaddr_is_v4mapped(addr, &addr4_copy)) { addr = (struct sockaddr *)&addr4_copy; addr_len = sizeof(addr4_copy); } sp2 = sp; errs[1] = add_socket_to_server(s, fd, addr, addr_len, port_index, fd_index, &sp); if (sp2 != NULL && sp != NULL) { sp2->sibling = sp; sp->is_sibling = 1; } } done: gpr_free(allocated_addr); if (sp != NULL) { *out_port = sp->port; GRPC_ERROR_UNREF(errs[0]); GRPC_ERROR_UNREF(errs[1]); return GRPC_ERROR_NONE; } else { *out_port = -1; char *addr_str = grpc_sockaddr_to_uri(addr); grpc_error *err = grpc_error_set_str( GRPC_ERROR_CREATE_REFERENCING("Failed to add port to server", errs, GPR_ARRAY_SIZE(errs)), GRPC_ERROR_STR_TARGET_ADDRESS, addr_str); GRPC_ERROR_UNREF(errs[0]); GRPC_ERROR_UNREF(errs[1]); gpr_free(addr_str); return err; } } unsigned grpc_tcp_server_port_fd_count(grpc_tcp_server *s, unsigned port_index) { unsigned num_fds = 0; grpc_tcp_listener *sp; for (sp = s->head; sp && port_index != 0; sp = sp->next) { if (!sp->is_sibling) { --port_index; } } for (; sp; sp = sp->sibling, ++num_fds) ; return num_fds; } int grpc_tcp_server_port_fd(grpc_tcp_server *s, unsigned port_index, unsigned fd_index) { grpc_tcp_listener *sp; for (sp = s->head; sp && port_index != 0; sp = sp->next) { if (!sp->is_sibling) { --port_index; } } for (; sp && fd_index != 0; sp = sp->sibling, --fd_index) ; if (sp) { return sp->fd; } else { return -1; } } void grpc_tcp_server_start(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s, grpc_pollset **pollsets, size_t pollset_count, grpc_tcp_server_cb on_accept_cb, void *on_accept_cb_arg) { size_t i; grpc_tcp_listener *sp; GPR_ASSERT(on_accept_cb); gpr_mu_lock(&s->mu); GPR_ASSERT(!s->on_accept_cb); GPR_ASSERT(s->active_ports == 0); s->on_accept_cb = on_accept_cb; s->on_accept_cb_arg = on_accept_cb_arg; s->pollsets = pollsets; s->pollset_count = pollset_count; sp = s->head; while (sp != NULL) { if (s->so_reuseport && pollset_count > 1) { GPR_ASSERT(GRPC_LOG_IF_ERROR( "clone_port", clone_port(sp, (unsigned)(pollset_count - 1)))); for (i = 0; i < pollset_count; i++) { grpc_pollset_add_fd(exec_ctx, pollsets[i], sp->emfd); sp->read_closure.cb = on_read; sp->read_closure.cb_arg = sp; grpc_fd_notify_on_read(exec_ctx, sp->emfd, &sp->read_closure); s->active_ports++; sp = sp->next; } } else { for (i = 0; i < pollset_count; i++) { grpc_pollset_add_fd(exec_ctx, pollsets[i], sp->emfd); } sp->read_closure.cb = on_read; sp->read_closure.cb_arg = sp; grpc_fd_notify_on_read(exec_ctx, sp->emfd, &sp->read_closure); s->active_ports++; sp = sp->next; } } gpr_mu_unlock(&s->mu); } grpc_tcp_server *grpc_tcp_server_ref(grpc_tcp_server *s) { gpr_ref(&s->refs); return s; } void grpc_tcp_server_shutdown_starting_add(grpc_tcp_server *s, grpc_closure *shutdown_starting) { gpr_mu_lock(&s->mu); grpc_closure_list_append(&s->shutdown_starting, shutdown_starting, GRPC_ERROR_NONE); gpr_mu_unlock(&s->mu); } void grpc_tcp_server_unref(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) { if (gpr_unref(&s->refs)) { /* Complete shutdown_starting work before destroying. */ grpc_exec_ctx local_exec_ctx = GRPC_EXEC_CTX_INIT; gpr_mu_lock(&s->mu); grpc_exec_ctx_enqueue_list(&local_exec_ctx, &s->shutdown_starting, NULL); gpr_mu_unlock(&s->mu); if (exec_ctx == NULL) { grpc_exec_ctx_flush(&local_exec_ctx); tcp_server_destroy(&local_exec_ctx, s); grpc_exec_ctx_finish(&local_exec_ctx); } else { grpc_exec_ctx_finish(&local_exec_ctx); tcp_server_destroy(exec_ctx, s); } } } #endif