From f52c7ea9d045db3a1f313f92ef786cbb58594a50 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Sat, 2 Jun 2018 16:20:02 +0200 Subject: [PATCH] Add minimalistic syslog daemon For now this daemon simply dumps all syslog messages into seperate log files and doesn't do much parsing. Since the messages are readable ASCII anyway, this should not be to much of a problem and sufficient for debugging. Signed-off-by: David Oberhollenzer --- .gitignore | 1 + Makefile.am | 7 ++ configure.ac | 10 ++ services/Makemodule.am | 8 +- services/usyslogd | 6 ++ syslogd/Makemodule.am | 8 ++ syslogd/logfile.c | 69 ++++++++++++++ syslogd/logfile.h | 34 +++++++ syslogd/main.c | 209 +++++++++++++++++++++++++++++++++++++++++ 9 files changed, 349 insertions(+), 3 deletions(-) create mode 100644 services/usyslogd create mode 100644 syslogd/Makemodule.am create mode 100644 syslogd/logfile.c create mode 100644 syslogd/logfile.h create mode 100644 syslogd/main.c diff --git a/.gitignore b/.gitignore index 73b3efb..256a460 100644 --- a/.gitignore +++ b/.gitignore @@ -20,6 +20,7 @@ reboot shutdown killall5 runsvc +usyslogd services/sigkill services/sigterm diff --git a/Makefile.am b/Makefile.am index 0b24ded..09fa4ef 100644 --- a/Makefile.am +++ b/Makefile.am @@ -19,6 +19,10 @@ include initd/Makemodule.am include scripts/Makemodule.am include services/Makemodule.am +if USYSLOGD +include syslogd/Makemodule.am +endif + install-data-local: $(MKDIR_P) $(DESTDIR)$(SVCDIR) $(LN_S) $(TEMPLATEDIR)/loopback $(DESTDIR)$(SVCDIR)/loopback @@ -39,3 +43,6 @@ install-data-local: $(LN_S) $(TEMPLATEDIR)/sigkill $(DESTDIR)$(SVCDIR)/sigkill@reboot $(LN_S) $(TEMPLATEDIR)/sigterm $(DESTDIR)$(SVCDIR)/sigterm@reboot $(LN_S) $(TEMPLATEDIR)/ifcfg $(DESTDIR)$(SVCDIR)/ifcfg +if USYSLOGD + $(LN_S) $(TEMPLATEDIR)/usyslogd $(DESTDIR)$(SVCDIR)/usyslogd +endif diff --git a/configure.ac b/configure.ac index 8a4b4d9..c1c7788 100644 --- a/configure.ac +++ b/configure.ac @@ -37,6 +37,16 @@ UL_WARN_ADD([-pedantic]) AC_SUBST([WARN_CFLAGS]) +AC_ARG_WITH([usyslogd], + [AS_HELP_STRING([--without-usyslogd], [Build without syslog daemon])], + [case "${withval}" in + yes) AM_CONDITIONAL([USYSLOGD], [true]) ;; + no) AM_CONDITIONAL([USYSLOGD], [false]) ;; + *) AC_MSG_ERROR([bad value ${withval} for --without-usyslogd]) ;; + esac], + [AM_CONDITIONAL([USYSLOGD], [true])]) + + AC_CONFIG_HEADERS([lib/include/config.h]) AC_DEFINE_DIR(SVCDIR, sysconfdir/init.d, [Startup service directory]) AC_DEFINE_DIR(TEMPLATEDIR, datadir/init, [Service template directory]) diff --git a/services/Makemodule.am b/services/Makemodule.am index c11a365..e9e6ac7 100644 --- a/services/Makemodule.am +++ b/services/Makemodule.am @@ -8,10 +8,12 @@ init_DATA += services/vfs services/ifrename services/ifcfg init_DATA += services/dhcpcd services/dhcpcdmaster services/unbound init_DATA += services/dnsmasq +if USYSLOGD +init_DATA += services/usyslogd +endif + EXTRA_DIST += services/sysinit services/vfs services/agetty services/hostname EXTRA_DIST += services/hwclock services/loopback services/reboot EXTRA_DIST += services/shutdown services/sync services/sysctl services/tmpfs -EXTRA_DIST += services/dhcpcd services/dhcpcdmaster EXTRA_DIST += services/dhcpcd services/dhcpcdmaster services/unbound -EXTRA_DIST += services/dnsmasq - +EXTRA_DIST += services/usyslogd services/dnsmasq diff --git a/services/usyslogd b/services/usyslogd new file mode 100644 index 0000000..23bea3b --- /dev/null +++ b/services/usyslogd @@ -0,0 +1,6 @@ +description "starting usyslogd" +exec usyslogd +type respawn limit 5 +target boot +after hostname vfs +before sysinit \ No newline at end of file diff --git a/syslogd/Makemodule.am b/syslogd/Makemodule.am new file mode 100644 index 0000000..489acc9 --- /dev/null +++ b/syslogd/Makemodule.am @@ -0,0 +1,8 @@ +usyslogd_SOURCES = syslogd/main.c +usyslogd_SOURCES += syslogd/logfile.c syslogd/logfile.h +usyslogd_CPPFLAGS = $(AM_CPPFLAGS) +usyslogd_CFLAGS = $(AM_CFLAGS) +usyslogd_LDFLAGS = $(AM_LDFLAGS) +usyslogd_LDADD = libinit.a + +sbin_PROGRAMS += usyslogd diff --git a/syslogd/logfile.c b/syslogd/logfile.c new file mode 100644 index 0000000..a59f7e7 --- /dev/null +++ b/syslogd/logfile.c @@ -0,0 +1,69 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * Copyright (C) 2018 - David Oberhollenzer + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * 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, see . + */ +#include +#include +#include +#include +#include +#include + +#include "logfile.h" + + +logfile_t *logfile_create(const char *name) +{ + logfile_t *file; + + file = calloc(1, sizeof(*file) + strlen(name) + 1); + if (file == NULL) { + perror("calloc"); + return NULL; + } + + strcpy(file->name, name); + + file->fd = open(file->name, O_WRONLY | O_CREAT, 0640); + if (file->fd < 0) + goto fail; + + if (lseek(file->fd, 0, SEEK_END)) + goto fail; + + return file; +fail: + perror(file->name); + free(file); + return NULL; +} + +void logfile_destroy(logfile_t *file) +{ + close(file->fd); + free(file); +} + +void logfile_write(logfile_t *file, const char *format, ...) +{ + va_list ap; + + va_start(ap, format); + vdprintf(file->fd, format, ap); + va_end(ap); + + fsync(file->fd); +} diff --git a/syslogd/logfile.h b/syslogd/logfile.h new file mode 100644 index 0000000..58da272 --- /dev/null +++ b/syslogd/logfile.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * Copyright (C) 2018 - David Oberhollenzer + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * 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, see . + */ +#ifndef LOGFILE_H +#define LOGFILE_H + +typedef struct logfile_t { + struct logfile_t *next; + int fd; + + char name[]; +} logfile_t; + +logfile_t *logfile_create(const char *name); + +void logfile_destroy(logfile_t *file); + +void logfile_write(logfile_t *file, const char *format, ...); + +#endif /* LOGFILE_H */ diff --git a/syslogd/main.c b/syslogd/main.c new file mode 100644 index 0000000..a5702b7 --- /dev/null +++ b/syslogd/main.c @@ -0,0 +1,209 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * Copyright (C) 2018 - David Oberhollenzer + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * 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, see . + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "logfile.h" +#include "util.h" + + +#define SYSLOG_SOCKET "/dev/log" +#define SYSLOG_PATH "/var/log" + + +static volatile sig_atomic_t syslog_run = 1; +static logfile_t *logfiles = NULL; + +static const enum_map_t facilities[] = { + { "kernel.log", 0 }, + { "user.log", 1 }, + { "mail.log", 2 }, + { "daemon.log", 3 }, + { "auth.log", 4 }, + { "syslog.log", 5 }, + { "lpr.log", 6 }, + { "news.log", 7 }, + { "uucp.log", 8 }, + { "clock.log", 9 }, + { "authpriv.log", 10 }, + { "ftp.log", 11 }, + { "ntp.log", 12 }, + { "audit.log", 13 }, + { "alert.log", 14 }, + { "cron.log", 15 }, + { "local0.log", 16 }, + { "local1.log", 17 }, + { "local2.log", 18 }, + { "local3.log", 19 }, + { "local4.log", 20 }, + { "local5.log", 21 }, + { "local6.log", 22 }, + { "local7.log", 23 }, + { NULL, 0 }, +}; + +static const enum_map_t levels[] = { + { "emergency", 0 }, + { "alert", 1 }, + { "critical", 2 }, + { "error", 3 }, + { "warning", 4 }, + { "notice", 5 }, + { "info", 6 }, + { "debug", 7 }, + { NULL, 0 }, +}; + + +static int directory_setup(void) +{ + if (mkdir(SYSLOG_PATH, 0755)) { + if (errno != EEXIST) { + perror("mkdir " SYSLOG_PATH); + return -1; + } + } + + if (chdir(SYSLOG_PATH)) { + perror("cd " SYSLOG_PATH); + return -1; + } + + return 0; +} + +static void sighandler(int signo) +{ + switch (signo) { + case SIGINT: + case SIGTERM: + syslog_run = 0; + break; + default: + break; + } +} + +static void signal_setup(void) +{ + struct sigaction act; + + memset(&act, 0, sizeof(act)); + act.sa_handler = sighandler; + + sigaction(SIGINT, &act, NULL); + sigaction(SIGTERM, &act, NULL); +} + +static int print_to_log(int facility, int level, const char *data) +{ + const char *fac_name, *lvl_str; + logfile_t *log; + + fac_name = enum_to_name(facilities, facility); + if (fac_name == NULL) + return -1; + + lvl_str = enum_to_name(levels, level); + if (lvl_str == NULL) + return -1; + + for (log = logfiles; log != NULL; log = log->next) { + if (!strcmp(log->name, fac_name)) + break; + } + + if (log == NULL) { + log = logfile_create(fac_name); + if (log == NULL) + return -1; + log->next = logfiles; + logfiles = log; + } + + logfile_write(log, "[%s] %s", lvl_str, data); + return 0; +} + +static int handle_data(int fd) +{ + char buffer[2048], *ptr; + int i = 0, priority; + ssize_t ret; + + memset(buffer, 0, sizeof(buffer)); + + ret = read(fd, buffer, sizeof(buffer)); + if (ret <= 0) + return -1; + + for (ptr = buffer; isspace(*ptr); ++ptr) + ; + if (*(ptr++) != '<') + return -1; + if (!isdigit(*ptr)) + return -1; + for (priority = 0; isdigit(*ptr); ++ptr) + priority = priority * 10 + (*ptr) - '0'; + if (*(ptr++) != '>') + return -1; + while (isspace(*ptr)) + ++ptr; + + return print_to_log(priority >> 3, priority & 0x07, ptr); +} + +int main(void) +{ + int sfd, status = EXIT_FAILURE; + logfile_t *log; + + signal_setup(); + + sfd = mksock(SYSLOG_SOCKET, SOCK_FLAG_EVERYONE | SOCK_FLAG_DGRAM); + if (sfd < 0) + return EXIT_FAILURE; + + if (directory_setup()) + goto out; + + while (syslog_run) { + handle_data(sfd); + } + + status = EXIT_SUCCESS; +out: + while (logfiles != NULL) { + log = logfiles; + logfiles = logfiles->next; + + logfile_destroy(log); + } + if (sfd > 0) + close(sfd); + unlink(SYSLOG_SOCKET); + return status; +}