+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2013 David Strauss
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
- ***/
-
-#include <arpa/inet.h>
-#include <errno.h>
-#include <getopt.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <netdb.h>
-#include <sys/fcntl.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <unistd.h>
-
-#include "log.h"
-#include "sd-daemon.h"
-#include "sd-event.h"
-#include "socket-util.h"
-#include "util.h"
-
-#define BUFFER_SIZE 16384
-#define _cleanup_freeaddrinfo_ _cleanup_(freeaddrinfop)
-
-unsigned int total_clients = 0;
-
-DEFINE_TRIVIAL_CLEANUP_FUNC(struct addrinfo *, freeaddrinfo);
-
-struct proxy {
- int listen_fd;
- bool ignore_env;
- bool remote_is_inet;
- const char *remote_host;
- const char *remote_service;
-};
-
-struct connection {
- int fd;
- uint32_t events;
- sd_event_source *w;
- struct connection *c_destination;
- size_t buffer_filled_len;
- size_t buffer_sent_len;
- char buffer[BUFFER_SIZE];
-};
-
-static void free_connection(struct connection *c) {
- log_debug("Freeing fd=%d (conn %p).", c->fd, c);
- sd_event_source_unref(c->w);
- close(c->fd);
- free(c);
-}
-
-static int add_event_to_connection(struct connection *c, uint32_t events) {
- int r;
-
- log_debug("Have revents=%d. Adding revents=%d.", c->events, events);
-
- c->events |= events;
-
- r = sd_event_source_set_io_events(c->w, c->events);
- if (r < 0) {
- log_error("Error %d setting revents: %s", r, strerror(-r));
- return r;
- }
-
- r = sd_event_source_set_enabled(c->w, SD_EVENT_ON);
- if (r < 0) {
- log_error("Error %d enabling source: %s", r, strerror(-r));
- return r;
- }
-
- return 0;
-}
-
-static int remove_event_from_connection(struct connection *c, uint32_t events) {
- int r;
-
- log_debug("Have revents=%d. Removing revents=%d.", c->events, events);
-
- c->events &= ~events;
-
- r = sd_event_source_set_io_events(c->w, c->events);
- if (r < 0) {
- log_error("Error %d setting revents: %s", r, strerror(-r));
- return r;
- }
-
- if (c->events == 0) {
- r = sd_event_source_set_enabled(c->w, SD_EVENT_OFF);
- if (r < 0) {
- log_error("Error %d disabling source: %s", r, strerror(-r));
- return r;
- }
- }
-
- return 0;
-}
-
-static int send_buffer(struct connection *sender) {
- struct connection *receiver = sender->c_destination;
- ssize_t len;
- int r = 0;
-
- /* We cannot assume that even a partial send() indicates that
- * the next send() will block. Loop until it does. */
- while (sender->buffer_filled_len > sender->buffer_sent_len) {
- len = send(receiver->fd, sender->buffer + sender->buffer_sent_len, sender->buffer_filled_len - sender->buffer_sent_len, 0);
- log_debug("send(%d, ...)=%ld", receiver->fd, len);
- if (len < 0) {
- if (errno != EWOULDBLOCK && errno != EAGAIN) {
- log_error("Error %d in send to fd=%d: %m", errno, receiver->fd);
- return -errno;
- }
- else {
- /* send() is in a blocking state. */
- break;
- }
- }
-
- /* len < 0 can't occur here. len == 0 is possible but
- * undefined behavior for nonblocking send(). */
- assert(len > 0);
- sender->buffer_sent_len += len;
- }
-
- log_debug("send(%d, ...) completed with %lu bytes still buffered.", receiver->fd, sender->buffer_filled_len - sender->buffer_sent_len);
-
- /* Detect a would-block state or partial send. */
- if (sender->buffer_filled_len > sender->buffer_sent_len) {
-
- /* If the buffer is full, disable events coming for recv. */
- if (sender->buffer_filled_len == BUFFER_SIZE) {
- r = remove_event_from_connection(sender, EPOLLIN);
- if (r < 0) {
- log_error("Error %d disabling EPOLLIN for fd=%d: %s", r, sender->fd, strerror(-r));
- return r;
- }
- }
-
- /* Watch for when the recipient can be sent data again. */
- r = add_event_to_connection(receiver, EPOLLOUT);
- if (r < 0) {
- log_error("Error %d enabling EPOLLOUT for fd=%d: %s", r, receiver->fd, strerror(-r));
- return r;
- }
- log_debug("Done with recv for fd=%d. Waiting on send for fd=%d.", sender->fd, receiver->fd);
- return r;
- }
-
- /* If we sent everything without blocking, the buffer is now empty. */
- sender->buffer_filled_len = 0;
- sender->buffer_sent_len = 0;
-
- /* Enable the sender's receive watcher, in case the buffer was
- * full and we disabled it. */
- r = add_event_to_connection(sender, EPOLLIN);
- if (r < 0) {
- log_error("Error %d enabling EPOLLIN for fd=%d: %s", r, sender->fd, strerror(-r));
- return r;
- }
-
- /* Disable the other side's send watcher, as we have no data to send now. */
- r = remove_event_from_connection(receiver, EPOLLOUT);
- if (r < 0) {
- log_error("Error %d disabling EPOLLOUT for fd=%d: %s", r, receiver->fd, strerror(-r));
- return r;
- }
-
- return 0;
-}
-
-static int transfer_data_cb(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
- struct connection *c = (struct connection *) userdata;
- int r = 0;
- ssize_t len;
-
- assert(revents & (EPOLLIN | EPOLLOUT));
- assert(fd == c->fd);
- assert(s == c->w);
-
- log_debug("Got event revents=%d from fd=%d (conn %p).", revents, fd, c);
-
- if (revents & EPOLLIN) {
- log_debug("About to recv up to %lu bytes from fd=%d (%lu/BUFFER_SIZE).", BUFFER_SIZE - c->buffer_filled_len, fd, c->buffer_filled_len);
-
- /* Receive until the buffer's full, there's no more data,
- * or the client/server disconnects. */
- while (c->buffer_filled_len < BUFFER_SIZE) {
- len = recv(fd, c->buffer + c->buffer_filled_len, BUFFER_SIZE - c->buffer_filled_len, 0);
- log_debug("recv(%d, ...)=%ld", fd, len);
- if (len < 0) {
- if (errno != EWOULDBLOCK && errno != EAGAIN) {
- log_error("Error %d in recv from fd=%d: %m", errno, fd);
- return -errno;
- }
- else {
- /* recv() is in a blocking state. */
- break;
- }
- }
- else if (len == 0) {
- log_debug("Clean disconnection from fd=%d", fd);
- total_clients--;
- free_connection(c->c_destination);
- free_connection(c);
- return 0;
- }
-
- assert(len > 0);
- log_debug("Recording that the buffer got %ld more bytes full.", len);
- c->buffer_filled_len += len;
- log_debug("Buffer now has %ld bytes full.", c->buffer_filled_len);
- }
-
- /* Try sending the data immediately. */
- return send_buffer(c);
- }
- else {
- return send_buffer(c->c_destination);
- }
-
- return r;
-}
-
-/* Once sending to the server is unblocked, set up the real watchers. */
-static int connected_to_server_cb(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
- struct sd_event *e = NULL;
- struct connection *c_server_to_client = (struct connection *) userdata;
- struct connection *c_client_to_server = c_server_to_client->c_destination;
- int r;
-
- assert(revents & EPOLLOUT);
-
- e = sd_event_get(s);
-
- /* Cancel the initial write watcher for the server. */
- sd_event_source_unref(s);
-
- log_debug("Connected to server. Initializing watchers for receiving data.");
-
- /* A recv watcher for the server. */
- r = sd_event_add_io(e, c_server_to_client->fd, EPOLLIN, transfer_data_cb, c_server_to_client, &c_server_to_client->w);
- if (r < 0) {
- log_error("Error %d creating recv watcher for fd=%d: %s", r, c_server_to_client->fd, strerror(-r));
- goto fail;
- }
- c_server_to_client->events = EPOLLIN;
-
- /* A recv watcher for the client. */
- r = sd_event_add_io(e, c_client_to_server->fd, EPOLLIN, transfer_data_cb, c_client_to_server, &c_client_to_server->w);
- if (r < 0) {
- log_error("Error %d creating recv watcher for fd=%d: %s", r, c_client_to_server->fd, strerror(-r));
- goto fail;
- }
- c_client_to_server->events = EPOLLIN;
-
-goto finish;
-
-fail:
- free_connection(c_client_to_server);
- free_connection(c_server_to_client);
-
-finish:
- return r;
-}
-
-static int get_server_connection_fd(const struct proxy *proxy) {
- int server_fd;
- int r = -EBADF;
- int len;
-
- if (proxy->remote_is_inet) {
- int s;
- _cleanup_freeaddrinfo_ struct addrinfo *result = NULL;
- struct addrinfo hints = {.ai_family = AF_UNSPEC,
- .ai_socktype = SOCK_STREAM,
- .ai_flags = AI_PASSIVE};
-
- log_debug("Looking up address info for %s:%s", proxy->remote_host, proxy->remote_service);
- s = getaddrinfo(proxy->remote_host, proxy->remote_service, &hints, &result);
- if (s != 0) {
- log_error("getaddrinfo error (%d): %s", s, gai_strerror(s));
- return r;
- }
-
- if (result == NULL) {
- log_error("getaddrinfo: no result");
- return r;
- }
-
- /* @TODO: Try connecting to all results instead of just the first. */
- server_fd = socket(result->ai_family, result->ai_socktype | SOCK_NONBLOCK, result->ai_protocol);
- if (server_fd < 0) {
- log_error("Error %d creating socket: %m", errno);
- return r;
- }
-
- r = connect(server_fd, result->ai_addr, result->ai_addrlen);
- /* Ignore EINPROGRESS errors because they're expected for a nonblocking socket. */
- if (r < 0 && errno != EINPROGRESS) {
- log_error("Error %d while connecting to socket %s:%s: %m", errno, proxy->remote_host, proxy->remote_service);
- return r;
- }
- }
- else {
- struct sockaddr_un remote;
-
- server_fd = socket(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, 0);
- if (server_fd < 0) {
- log_error("Error %d creating socket: %m", errno);
- return -EBADFD;
- }
-
- remote.sun_family = AF_UNIX;
- strncpy(remote.sun_path, proxy->remote_host, sizeof(remote.sun_path));
- len = strlen(remote.sun_path) + sizeof(remote.sun_family);
- r = connect(server_fd, (struct sockaddr *) &remote, len);
- if (r < 0 && errno != EINPROGRESS) {
- log_error("Error %d while connecting to Unix domain socket %s: %m", errno, proxy->remote_host);
- return -EBADFD;
- }
- }
-
- log_debug("Server connection is fd=%d", server_fd);
- return server_fd;
-}
-
-static int accept_cb(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
- struct proxy *proxy = (struct proxy *) userdata;
- struct connection *c_server_to_client;
- struct connection *c_client_to_server;
- int r = 0;
- union sockaddr_union sa;
- socklen_t salen = sizeof(sa);
-
- assert(revents & EPOLLIN);
-
- c_server_to_client = malloc0(sizeof(struct connection));
- if (c_server_to_client == NULL) {
- log_oom();
- goto fail;
- }
-
- c_client_to_server = malloc0(sizeof(struct connection));
- if (c_client_to_server == NULL) {
- log_oom();
- goto fail;
- }
-
- c_server_to_client->fd = get_server_connection_fd(proxy);
- if (c_server_to_client->fd < 0) {
- log_error("Error initiating server connection.");
- goto fail;
- }
-
- c_client_to_server->fd = accept(fd, (struct sockaddr *) &sa, &salen);
- if (c_client_to_server->fd < 0) {
- log_error("Error accepting client connection.");
- goto fail;
- }
-
- /* Unlike on BSD, client sockets do not inherit nonblocking status
- * from the listening socket. */
- r = fd_nonblock(c_client_to_server->fd, true);
- if (r < 0) {
- log_error("Error %d marking client connection as nonblocking: %s", r, strerror(-r));
- goto fail;
- }
-
- if (sa.sa.sa_family == AF_INET || sa.sa.sa_family == AF_INET6) {
- char sa_str[INET6_ADDRSTRLEN];
- const char *success;
-
- success = inet_ntop(sa.sa.sa_family, &sa.in6.sin6_addr, sa_str, INET6_ADDRSTRLEN);
- if (success == NULL)
- log_warning("Error %d calling inet_ntop: %m", errno);
- else
- log_debug("Accepted client connection from %s as fd=%d", sa_str, c_client_to_server->fd);
- }
- else {
- log_debug("Accepted client connection (non-IP) as fd=%d", c_client_to_server->fd);
- }
-
- total_clients++;
- log_debug("Client fd=%d (conn %p) successfully connected. Total clients: %u", c_client_to_server->fd, c_client_to_server, total_clients);
- log_debug("Server fd=%d (conn %p) successfully initialized.", c_server_to_client->fd, c_server_to_client);
-
- /* Initialize watcher for send to server; this shows connectivity. */
- r = sd_event_add_io(sd_event_get(s), c_server_to_client->fd, EPOLLOUT, connected_to_server_cb, c_server_to_client, &c_server_to_client->w);
- if (r < 0) {
- log_error("Error %d creating connectivity watcher for fd=%d: %s", r, c_server_to_client->fd, strerror(-r));
- goto fail;
- }
-
- /* Allow lookups of the opposite connection. */
- c_server_to_client->c_destination = c_client_to_server;
- c_client_to_server->c_destination = c_server_to_client;
-
- goto finish;
-
-fail:
- log_warning("Accepting a client connection or connecting to the server failed.");
- free_connection(c_client_to_server);
- free_connection(c_server_to_client);
-
-finish:
- /* Preserve the main loop even if a single proxy setup fails. */
- return 0;
-}
-
-static int run_main_loop(struct proxy *proxy) {
- int r = EXIT_SUCCESS;
- struct sd_event *e = NULL;
- sd_event_source *w_accept = NULL;
-
- r = sd_event_new(&e);
- if (r < 0)
- goto finish;
-
- r = fd_nonblock(proxy->listen_fd, true);
- if (r < 0)
- goto finish;
-
- log_debug("Initializing main listener fd=%d", proxy->listen_fd);
-
- sd_event_add_io(e, proxy->listen_fd, EPOLLIN, accept_cb, proxy, &w_accept);
-
- log_debug("Initialized main listener. Entering loop.");
-
- sd_event_loop(e);
-
-finish:
- sd_event_source_unref(w_accept);
- sd_event_unref(e);
-
- return r;
-}
-
-static int help(void) {
-
- printf("%s hostname-or-ip port-or-service\n"
- "%s unix-domain-socket-path\n\n"
- "Inherit a socket. Bidirectionally proxy.\n\n"
- " -h --help Show this help\n"
- " --version Print version and exit\n"
- " --ignore-env Ignore expected systemd environment\n",
- program_invocation_short_name,
- program_invocation_short_name);
-
- return 0;
-}
-
-static void version(void) {
- puts(PACKAGE_STRING " saproxy");
-}
-
-static int parse_argv(int argc, char *argv[], struct proxy *p) {
-
- enum {
- ARG_VERSION = 0x100,
- ARG_IGNORE_ENV
- };
-
- static const struct option options[] = {
- { "help", no_argument, NULL, 'h' },
- { "version", no_argument, NULL, ARG_VERSION },
- { "ignore-env", no_argument, NULL, ARG_IGNORE_ENV},
- { NULL, 0, NULL, 0 }
- };
-
- int c;
-
- assert(argc >= 0);
- assert(argv);
-
- while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
-
- switch (c) {
-
- case 'h':
- help();
- return 0;
-
- case '?':
- return -EINVAL;
-
- case ARG_VERSION:
- version();
- return 0;
-
- case ARG_IGNORE_ENV:
- p->ignore_env = true;
- continue;
-
- default:
- log_error("Unknown option code %c", c);
- return -EINVAL;
- }
- }
-
- if (optind + 1 != argc && optind + 2 != argc) {
- log_error("Incorrect number of positional arguments.");
- help();
- return -EINVAL;
- }
-
- p->remote_host = argv[optind];
- assert(p->remote_host);
-
- p->remote_is_inet = p->remote_host[0] != '/';
-
- if (optind == argc - 2) {
- if (!p->remote_is_inet) {
- log_error("A port or service is not allowed for Unix socket destinations.");
- help();
- return -EINVAL;
- }
- p->remote_service = argv[optind + 1];
- assert(p->remote_service);
- } else if (p->remote_is_inet) {
- log_error("A port or service is required for IP destinations.");
- help();
- return -EINVAL;
- }
-
- return 1;
-}
-
-int main(int argc, char *argv[]) {
- struct proxy p = {};
- int r;
-
- log_parse_environment();
- log_open();
-
- r = parse_argv(argc, argv, &p);
- if (r <= 0)
- goto finish;
-
- p.listen_fd = SD_LISTEN_FDS_START;
-
- if (!p.ignore_env) {
- int n;
- n = sd_listen_fds(1);
- if (n == 0) {
- log_error("Found zero inheritable sockets. Are you sure this is running as a socket-activated service?");
- r = EXIT_FAILURE;
- goto finish;
- } else if (n < 0) {
- log_error("Error %d while finding inheritable sockets: %s", n, strerror(-n));
- r = EXIT_FAILURE;
- goto finish;
- } else if (n > 1) {
- log_error("Can't listen on more than one socket.");
- r = EXIT_FAILURE;
- goto finish;
- }
- }
-
- /* @TODO: Check if this proxy can work with datagram sockets. */
- r = sd_is_socket(p.listen_fd, 0, SOCK_STREAM, 1);
- if (r < 0) {
- log_error("Error %d while checking inherited socket: %s", r, strerror(-r));
- goto finish;
- }
-
- log_info("Starting the socket activation proxy with listener fd=%d.", p.listen_fd);
-
- r = run_main_loop(&p);
- if (r < 0) {
- log_error("Error %d from main loop.", r);
- goto finish;
- }
-
-finish:
- log_close();
- return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
-}
~ianmdlvl / elogind.git / blobdiff