journal-remote: tool to receive messages over the network

1 files changed, 738 insertions, 0 deletions

diff --git a/src/journal/journal-remote.c b/src/journal/journal-remote.c
new file mode 100644
index 0000000000..f8979daca6
--- /dev/null
+++ b/src/journal/journal-remote.c
@@ -0,0 +1,738 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2012 Zbigniew Jędrzejewski-Szmek
+
+  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 <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/prctl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <getopt.h>
+
+#include "sd-daemon.h"
+#include "sd-event.h"
+#include "journal-file.h"
+#include "journald-native.h"
+#include "socket-util.h"
+#include "mkdir.h"
+#include "build.h"
+#include "macro.h"
+#include "strv.h"
+
+#include "journal-remote-parse.h"
+#include "journal-remote-write.h"
+
+#define REMOTE_JOURNAL_PATH "/var/log/journal/" SD_ID128_FORMAT_STR "/remote-%s.journal"
+
+static char* arg_output = NULL;
+static char* arg_url = NULL;
+static char* arg_getter = NULL;
+static bool arg_stdin = false;
+static char* arg_listen_raw = NULL;
+static int arg_compress = true;
+static int arg_seal = false;
+
+/**********************************************************************
+ **********************************************************************
+ **********************************************************************/
+
+static int spawn_child(const char* child, char** argv) {
+        int fd[2];
+        pid_t parent_pid, child_pid;
+        int r;
+
+        if (pipe(fd) < 0) {
+                log_error("Failed to create pager pipe: %m");
+                return -errno;
+        }
+
+        parent_pid = getpid();
+
+        child_pid = fork();
+        if (child_pid < 0) {
+                r = -errno;
+                log_error("Failed to fork: %m");
+                close_pipe(fd);
+                return r;
+        }
+
+        /* In the child */
+        if (child_pid == 0) {
+                r = dup2(fd[1], STDOUT_FILENO);
+                if (r < 0) {
+                        log_error("Failed to dup pipe to stdout: %m");
+                        _exit(EXIT_FAILURE);
+                }
+
+                r = close_pipe(fd);
+                if (r < 0)
+                        log_warning("Failed to close pipe fds: %m");
+
+                /* Make sure the child goes away when the parent dies */
+                if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
+                        _exit(EXIT_FAILURE);
+
+                /* Check whether our parent died before we were able
+                 * to set the death signal */
+                if (getppid() != parent_pid)
+                        _exit(EXIT_SUCCESS);
+
+                execvp(child, argv);
+                log_error("Failed to exec child %s: %m", child);
+                _exit(EXIT_FAILURE);
+        }
+
+        r = close(fd[1]);
+        if (r < 0)
+                log_warning("Failed to close write end of pipe: %m");
+
+        return fd[0];
+}
+
+static int spawn_curl(char* url) {
+        char **argv = STRV_MAKE("curl",
+                                "-HAccept: application/vnd.fdo.journal",
+                                "--silent",
+                                "--show-error",
+                                url);
+        int r;
+
+        r = spawn_child("curl", argv);
+        if (r < 0)
+                log_error("Failed to spawn curl: %m");
+        return r;
+}
+
+static int spawn_getter(char *getter, char *url) {
+        int r;
+        char _cleanup_strv_free_ **words = NULL, **words2 = NULL;
+
+        assert(getter);
+        words = strv_split_quoted(getter);
+        if (!words)
+                return log_oom();
+
+        r = spawn_child(words[0], words);
+        if (r < 0)
+                log_error("Failed to spawn getter %s: %m", getter);
+
+        return r;
+}
+
+static int open_output(Writer *s, const char* url) {
+        char _cleanup_free_ *name, *output = NULL;
+        char *c;
+        int r;
+
+        assert(url);
+        name = strdup(url);
+        if (!name)
+                return log_oom();
+
+        for(c = name; *c; c++) {
+                if (*c == '/' || *c == ':' || *c == ' ')
+                        *c = '~';
+                else if (*c == '?') {
+                        *c = '\0';
+                        break;
+                }
+        }
+
+        if (!arg_output) {
+                sd_id128_t machine;
+                r = sd_id128_get_machine(&machine);
+                if (r < 0) {
+                        log_error("failed to determine machine ID128: %s", strerror(-r));
+                        return r;
+                }
+
+                r = asprintf(&output, REMOTE_JOURNAL_PATH,
+                             SD_ID128_FORMAT_VAL(machine), name);
+                if (r < 0)
+                        return log_oom();
+        } else {
+                r = is_dir(arg_output);
+                if (r > 0) {
+                        r = asprintf(&output,
+                                     "%s/remote-%s.journal", arg_output, name);
+                        if (r < 0)
+                                return log_oom();
+                } else {
+                        output = strdup(arg_output);
+                        if (!output)
+                                return log_oom();
+                }
+        }
+
+        r = journal_file_open_reliably(output,
+                                       O_RDWR|O_CREAT, 0640,
+                                       arg_compress, arg_seal,
+                                       &s->metrics,
+                                       s->mmap,
+                                       NULL, &s->journal);
+        if (r < 0)
+                log_error("Failed to open output journal %s: %s",
+                          arg_output, strerror(-r));
+        else
+                log_info("Opened output file %s", s->journal->path);
+        return r;
+}
+
+typedef struct RemoteServer {
+        RemoteSource **sources;
+        ssize_t sources_size;
+        ssize_t active;
+
+        sd_event *events;
+        sd_event_source *sigterm_event, *sigint_event, *listen_event;
+
+        Writer writer;
+} RemoteServer;
+
+static int dispatch_raw_source_event(sd_event_source *event,
+                                     int fd,
+                                     uint32_t revents,
+                                     void *userdata);
+static int dispatch_raw_connection_event(sd_event_source *event,
+                                         int fd,
+                                         uint32_t revents,
+                                         void *userdata);
+
+static int get_source_for_fd(RemoteServer *s, int fd, RemoteSource **source) {
+        assert(fd >= 0);
+        assert(source);
+
+        if (!GREEDY_REALLOC0_T(s->sources, s->sources_size, fd + 1))
+                return log_oom();
+
+        if (s->sources[fd] == NULL) {
+                s->sources[fd] = new0(RemoteSource, 1);
+                if (!s->sources[fd])
+                        return log_oom();
+                s->sources[fd]->fd = -1;
+                s->active++;
+        }
+
+        *source = s->sources[fd];
+        return 0;
+}
+
+static int remove_source(RemoteServer *s, int fd) {
+        RemoteSource *source;
+
+        assert(s);
+        assert(fd >= 0);
+        assert(fd < s->sources_size);
+
+        source = s->sources[fd];
+        if (source) {
+                source_free(source);
+                s->sources[fd] = NULL;
+                s->active--;
+        }
+
+        close(fd);
+
+        return 0;
+}
+
+static int add_source(RemoteServer *s, int fd, const char* name) {
+        RemoteSource *source = NULL;
+        char *realname;
+        int r;
+
+        assert(s);
+        assert(fd >= 0);
+
+        if (name) {
+                realname = strdup(name);
+                if (!realname)
+                        return log_oom();
+        } else {
+                r = asprintf(&realname, "fd:%d", fd);
+                if (r < 0)
+                        return log_oom();
+        }
+
+        log_debug("Creating source for fd:%d (%s)", fd, name);
+
+        r = get_source_for_fd(s, fd, &source);
+        if (r < 0) {
+                log_error("Failed to create source for fd:%d (%s)", fd, name);
+                return r;
+        }
+        assert(source);
+        assert(source->fd < 0);
+        source->fd = fd;
+
+        r = sd_event_add_io(s->events, &source->event,
+                            fd, EPOLLIN, dispatch_raw_source_event, s);
+        if (r < 0) {
+                log_error("Failed to register event source for fd:%d: %s",
+                          fd, strerror(-r));
+                goto error;
+        }
+
+        return 1; /* work to do */
+
+ error:
+        remove_source(s, fd);
+        return r;
+}
+
+static int setup_raw_socket(RemoteServer *s, const char *address) {
+        int fd, r;
+
+        fd = make_socket_fd(LOG_INFO, address, SOCK_STREAM | SOCK_CLOEXEC);
+        if (fd < 0)
+                return fd;
+
+        r = sd_event_add_io(s->events, &s->listen_event, fd, EPOLLIN,
+                            dispatch_raw_connection_event, s);
+        if (r < 0) {
+                close(fd);
+                return r;
+        }
+
+        s->active ++;
+        return 0;
+}
+
+/**********************************************************************
+ **********************************************************************
+ **********************************************************************/
+
+static int dispatch_sigterm(sd_event_source *event,
+                            const struct signalfd_siginfo *si,
+                            void *userdata) {
+        RemoteServer *s = userdata;
+
+        assert(s);
+
+        log_received_signal(LOG_INFO, si);
+
+        sd_event_exit(s->events, 0);
+        return 0;
+}
+
+static int setup_signals(RemoteServer *s) {
+        sigset_t mask;
+        int r;
+
+        assert(s);
+
+        assert_se(sigemptyset(&mask) == 0);
+        sigset_add_many(&mask, SIGINT, SIGTERM, -1);
+        assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
+
+        r = sd_event_add_signal(s->events, &s->sigterm_event, SIGTERM, dispatch_sigterm, s);
+        if (r < 0)
+                return r;
+
+        r = sd_event_add_signal(s->events, &s->sigint_event, SIGINT, dispatch_sigterm, s);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
+static int remoteserver_init(RemoteServer *s) {
+        int r, n, fd;
+        const char *output_name = NULL;
+
+        assert(s);
+
+        sd_event_default(&s->events);
+
+        setup_signals(s);
+
+        n = sd_listen_fds(true);
+        if (n < 0) {
+                log_error("Failed to read listening file descriptors from environment: %s",
+                          strerror(-n));
+                return n;
+        } else
+                log_info("Received %d descriptors", n);
+
+        for (fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + n; fd++) {
+                if (sd_is_socket(fd, AF_UNSPEC, 0, false)) {
+                        assert_not_reached("not implemented");
+                } else if (sd_is_socket(fd, AF_UNSPEC, 0, true)) {
+                        log_info("Received a connection socket (fd:%d)", fd);
+
+                        r = add_source(s, fd, NULL);
+                        output_name = "socket";
+                } else {
+                        log_error("Unknown socket passed on fd:%d", fd);
+                        return -EINVAL;
+                }
+        }
+
+        if (arg_url) {
+                char _cleanup_free_ *url = NULL;
+                char _cleanup_strv_free_ **urlv = strv_new(arg_url, "/entries", NULL);
+                if (!urlv)
+                        return log_oom();
+                url = strv_join(urlv, "");
+                if (!url)
+                        return log_oom();
+
+                if (arg_getter) {
+                        log_info("Spawning getter %s...", url);
+                        fd = spawn_getter(arg_getter, url);
+                } else {
+                        log_info("Spawning curl %s...", url);
+                        fd = spawn_curl(url);
+                }
+                if (fd < 0)
+                        return fd;
+
+                r = add_source(s, fd, arg_url);
+                if (r < 0)
+                        return r;
+
+                output_name = arg_url;
+        }
+
+        if (arg_listen_raw) {
+                log_info("Listening on a socket...");
+                r = setup_raw_socket(s, arg_listen_raw);
+                if (r < 0)
+                        return r;
+
+                output_name = arg_listen_raw;
+        }
+
+        if (arg_stdin) {
+                log_info("Reading standard input...");
+                r = add_source(s, STDIN_FILENO, "stdin");
+                if (r < 0)
+                        return r;
+
+                output_name = "stdin";
+        }
+
+        if (s->active == 0) {
+                log_error("Zarro sources specified");
+                return -EINVAL;
+        }
+
+        if (!!n + !!arg_url + !!arg_listen_raw + !!arg_stdin > 1)
+                output_name = "multiple";
+
+        r = writer_init(&s->writer);
+        if (r < 0)
+                return r;
+
+        r = open_output(&s->writer, output_name);
+        return r;
+}
+
+static int server_destroy(RemoteServer *s) {
+        int r;
+        ssize_t i;
+
+        r = writer_close(&s->writer);
+
+        assert(s->sources_size == 0 || s->sources);
+        for(i = 0; i < s->sources_size; i++)
+                remove_source(s, i);
+
+        free(s->sources);
+
+        sd_event_source_unref(s->sigterm_event);
+        sd_event_source_unref(s->sigint_event);
+        sd_event_source_unref(s->listen_event);
+        sd_event_unref(s->events);
+
+        /* fds that we're listening on remain open... */
+
+        return r;
+}
+
+/**********************************************************************
+ **********************************************************************
+ **********************************************************************/
+
+static int dispatch_raw_source_event(sd_event_source *event,
+                                     int fd,
+                                     uint32_t revents,
+                                     void *userdata) {
+
+        RemoteServer *s = userdata;
+        RemoteSource *source;
+        int r;
+
+        assert(fd < s->sources_size);
+        source = s->sources[fd];
+        assert(source->fd == fd);
+
+        r = process_source(source, &s->writer, arg_compress, arg_seal);
+        if (source->state == STATE_EOF) {
+                log_info("EOF reached with source fd:%d (%s)",
+                         source->fd, source->name);
+                if (source_non_empty(source))
+                        log_warning("EOF reached with incomplete data");
+                remove_source(s, source->fd);
+                log_info("%zd active source remaining", s->active);
+        } else if (r == -E2BIG) {
+                log_error("Entry too big, skipped");
+                r = 1;
+        }
+
+        return r;
+}
+
+static int dispatch_raw_connection_event(sd_event_source *event,
+                                         int fd,
+                                         uint32_t revents,
+                                         void *userdata) {
+        RemoteServer *s = userdata;
+
+        SocketAddress addr = {
+                .size = sizeof(union sockaddr_union),
+                .type = SOCK_STREAM,
+        };
+        int fd2, r;
+
+        log_debug("Accepting new connection on fd:%d", fd);
+        fd2 = accept4(fd, &addr.sockaddr.sa, &addr.size, SOCK_NONBLOCK|SOCK_CLOEXEC);
+        if (fd2 < 0) {
+                log_error("accept() on fd:%d failed: %m", fd);
+                return -errno;
+        }
+
+        switch(socket_address_family(&addr)) {
+        case AF_INET:
+        case AF_INET6: {
+                char* _cleanup_free_ a = NULL;
+
+                r = socket_address_print(&addr, &a);
+                if (r < 0) {
+                        log_error("socket_address_print(): %s", strerror(-r));
+                        close(fd2);
+                        return r;
+                }
+
+                log_info("Accepted %s connection from %s",
+                         socket_address_family(&addr) == AF_INET ? "IP" : "IPv6",
+                         a);
+                break;
+        };
+        default:
+                log_error("Connection with unsupported family %d",
+                          socket_address_family(&addr));
+                close(fd2);
+                return -EINVAL;
+        }
+
+        r = add_source(s, fd2, NULL);
+        if (r < 0)
+                log_error("failed to create source from fd:%d: %s", fd2, strerror(-r));
+
+        return r;
+}
+
+
+/**********************************************************************
+ **********************************************************************
+ **********************************************************************/
+
+static int help(void) {
+        printf("%s [OPTIONS...]\n\n"
+               "Write external journal events to a journal file.\n\n"
+               "Options:\n"
+               "  --url=URL            Read events from systemd-journal-gatewayd at URL\n"
+               "  --getter=COMMAND     Read events from the output of COMMAND\n"
+               "  --listen-raw=ADDR    Listen for connections at ADDR\n"
+               "  --stdin              Read events from standard input\n"
+               "  -o --output=FILE|DIR Write output to FILE or DIR/external-*.journal\n"
+               "  --[no-]compress      Use XZ-compression in the output journal (default: yes)\n"
+               "  --[no-]seal          Use Event sealing in the output journal (default: no)\n"
+               "  -h --help            Show this help and exit\n"
+               "  --version            Print version string and exit\n"
+               "\n"
+               "Note: file descriptors from sd_listen_fds() will be consumed, too.\n"
+               , program_invocation_short_name);
+
+        return 0;
+}
+
+static int parse_argv(int argc, char *argv[]) {
+        enum {
+                ARG_VERSION = 0x100,
+                ARG_URL,
+                ARG_LISTEN_RAW,
+                ARG_STDIN,
+                ARG_GETTER,
+                ARG_COMPRESS,
+                ARG_NO_COMPRESS,
+                ARG_SEAL,
+                ARG_NO_SEAL,
+        };
+
+        static const struct option options[] = {
+                { "help",         no_argument,       NULL, 'h'              },
+                { "version",      no_argument,       NULL, ARG_VERSION      },
+                { "url",          required_argument, NULL, ARG_URL          },
+                { "getter",       required_argument, NULL, ARG_GETTER       },
+                { "listen-raw",   required_argument, NULL, ARG_LISTEN_RAW   },
+                { "stdin",        no_argument,       NULL, ARG_STDIN        },
+                { "output",       required_argument, NULL, 'o'              },
+                { "compress",     no_argument,       NULL, ARG_COMPRESS     },
+                { "no-compress",  no_argument,       NULL, ARG_NO_COMPRESS  },
+                { "seal",         no_argument,       NULL, ARG_SEAL         },
+                { "no-seal",      no_argument,       NULL, ARG_NO_SEAL      },
+                {}
+        };
+
+        int c;
+
+        assert(argc >= 0);
+        assert(argv);
+
+        while ((c = getopt_long(argc, argv, "ho:", options, NULL)) >= 0)
+                switch(c) {
+                case 'h':
+                        help();
+                        return 0 /* done */;
+
+                case ARG_VERSION:
+                        puts(PACKAGE_STRING);
+                        puts(SYSTEMD_FEATURES);
+                        return 0 /* done */;
+
+                case ARG_URL:
+                        if (arg_url) {
+                                log_error("cannot currently set more than one --url");
+                                return -EINVAL;
+                        }
+
+                        arg_url = optarg;
+                        break;
+
+                case ARG_GETTER:
+                        if (arg_getter) {
+                                log_error("cannot currently use --getter more than once");
+                                return -EINVAL;
+                        }
+
+                        arg_getter = optarg;
+                        break;
+
+                case ARG_LISTEN_RAW:
+                        if (arg_listen_raw) {
+                                log_error("cannot currently use --listen-raw more than once");
+                                return -EINVAL;
+                        }
+
+                        arg_listen_raw = optarg;
+                        break;
+
+                case ARG_STDIN:
+                        arg_stdin = true;
+                        break;
+
+                case 'o':
+                        if (arg_output) {
+                                log_error("cannot use --output/-o more than once");
+                                return -EINVAL;
+                        }
+
+                        arg_output = optarg;
+                        break;
+
+                case ARG_COMPRESS:
+                        arg_compress = true;
+                        break;
+                case ARG_NO_COMPRESS:
+                        arg_compress = false;
+                        break;
+                case ARG_SEAL:
+                        arg_seal = true;
+                        break;
+                case ARG_NO_SEAL:
+                        arg_seal = false;
+                        break;
+
+                case '?':
+                        return -EINVAL;
+
+                default:
+                        log_error("Unknown option code %c", c);
+                        return -EINVAL;
+                }
+
+        if (optind < argc) {
+                log_error("This program takes no positional arguments");
+                return -EINVAL;
+        }
+
+        return 1 /* work to do */;
+}
+
+int main(int argc, char **argv) {
+        RemoteServer s = {};
+        int r, r2;
+
+        log_set_max_level(LOG_DEBUG);
+        log_show_color(true);
+        log_parse_environment();
+
+        r = parse_argv(argc, argv);
+        if (r <= 0)
+                return r == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
+
+        if (remoteserver_init(&s) < 0)
+                return EXIT_FAILURE;
+
+        log_debug("%s running as pid %lu",
+                  program_invocation_short_name, (unsigned long) getpid());
+        sd_notify(false,
+                  "READY=1\n"
+                  "STATUS=Processing requests...");
+
+        while (s.active) {
+                r = sd_event_get_state(s.events);
+                if (r < 0)
+                        break;
+                if (r == SD_EVENT_FINISHED)
+                        break;
+
+                r = sd_event_run(s.events, -1);
+                if (r < 0) {
+                        log_error("Failed to run event loop: %s", strerror(-r));
+                        break;
+                }
+        }
+
+        log_info("Finishing after writing %" PRIu64 " entries", s.writer.seqnum);
+        r2 = server_destroy(&s);
+
+        sd_notify(false, "STATUS=Shutting down...");
+
+        return r >= 0 && r2 >= 0 ? EXIT_SUCCESS : EXIT_FAILURE;
+}