diff options
| -rw-r--r-- | .gitignore | 1 | ||||
| -rw-r--r-- | Makefile.am | 6 | ||||
| -rw-r--r-- | configure.ac | 9 | ||||
| -rw-r--r-- | docs/defconfig.md | 4 | ||||
| -rw-r--r-- | docs/usyslogd.md | 9 | ||||
| -rw-r--r-- | services/Makemodule.am | 6 | ||||
| -rw-r--r-- | services/klogd | 6 | ||||
| -rw-r--r-- | syslogd/Makemodule.am | 11 | ||||
| -rw-r--r-- | syslogd/klogd.c | 191 |
9 files changed, 238 insertions, 5 deletions
@@ -22,6 +22,7 @@ killall5 runsvc syslog usyslogd +klogd services/sigkill services/sigterm diff --git a/Makefile.am b/Makefile.am index 648631a..063a8e8 100644 --- a/Makefile.am +++ b/Makefile.am @@ -22,10 +22,7 @@ include cmd/Makemodule.am include initd/Makemodule.am include scripts/Makemodule.am include services/Makemodule.am - -if USYSLOGD include syslogd/Makemodule.am -endif install-exec-hook: (cd $(DESTDIR)$(sbindir); $(LN_S) shutdown reboot) @@ -57,3 +54,6 @@ install-data-local: if USYSLOGD $(LN_S) $(TEMPLATEDIR)/usyslogd $(DESTDIR)$(SVCDIR)/usyslogd endif +if KLOGD + $(LN_S) $(TEMPLATEDIR)/klogd $(DESTDIR)$(SVCDIR)/klogd +endif diff --git a/configure.ac b/configure.ac index 99e4b2d..01cff9e 100644 --- a/configure.ac +++ b/configure.ac @@ -46,6 +46,15 @@ AC_ARG_WITH([usyslogd], esac], [AM_CONDITIONAL([USYSLOGD], [true])]) +AC_ARG_WITH([klogd], + [AS_HELP_STRING([--without-klogd], [Build without kernel log daemon])], + [case "${withval}" in + yes) AM_CONDITIONAL([KLOGD], [true]) ;; + no) AM_CONDITIONAL([KLOGD], [false]) ;; + *) AC_MSG_ERROR([bad value ${withval} for --without-klogd]) ;; + esac], + [AM_CONDITIONAL([KLOGD], [true])]) + AC_CONFIG_HEADERS([lib/include/config.h]) AC_DEFINE_DIR(SVCDIR, sysconfdir/init.d, [Startup service directory]) diff --git a/docs/defconfig.md b/docs/defconfig.md index 10263ba..41afc02 100644 --- a/docs/defconfig.md +++ b/docs/defconfig.md @@ -55,8 +55,10 @@ the `vfs` target and *before* the `sysinit` target: * hostname - reload hostname `/etc/hostname` * loopback - bring the loopback device up - * usyslogd - if the `usyslogd` services is compiled with this package, this + * usyslogd - if the `usyslogd` service is compiled with this package, this service is enabled by default and starts `usyslogd`. + * klogd - if the `klogd` daemon is compiled with this package, this service + is enabled by default and starts after `usyslogd`. * modules - iterate over the file `/etc/modules` and try to load each module using modprobe. * sysctl - restore kernel parameters using `sysctl --system`. See `sysctl(8)` diff --git a/docs/usyslogd.md b/docs/usyslogd.md index 96f5755..525c475 100644 --- a/docs/usyslogd.md +++ b/docs/usyslogd.md @@ -12,6 +12,15 @@ the log messages into files in the processes working directory (by default A simple log rotation scheme has been implemented. +## Kernel Message Logging + +An additional small `klogd` daemon is provided that redirects kernel messages +to the syslog daemon. + +It can be enabled or disabled independently of the `usyslogd` daemon and is +designed to work with any other syslogd implementation. + + ## Security Considerations By default, the daemon switches its working directory to `/var/log`. The diff --git a/services/Makemodule.am b/services/Makemodule.am index 0843787..5e38eca 100644 --- a/services/Makemodule.am +++ b/services/Makemodule.am @@ -14,8 +14,12 @@ if USYSLOGD init_DATA += services/usyslogd endif +if USYSLOGD +init_DATA += services/klogd +endif + EXTRA_DIST += services/sysinit services/vfs services/agetty services/hostname -EXTRA_DIST += services/hwclock services/loopback +EXTRA_DIST += services/hwclock services/loopback services/klogd EXTRA_DIST += services/sync services/sysctl services/tmpfs EXTRA_DIST += services/dhcpcd services/dhcpcdmaster services/unbound EXTRA_DIST += services/usyslogd services/dnsmasq services/network diff --git a/services/klogd b/services/klogd new file mode 100644 index 0000000..aaca59a --- /dev/null +++ b/services/klogd @@ -0,0 +1,6 @@ +description "starting uklogd" +exec klogd +type respawn limit 5 +target boot +after usyslogd +before sysinit diff --git a/syslogd/Makemodule.am b/syslogd/Makemodule.am index 022946b..ab61b87 100644 --- a/syslogd/Makemodule.am +++ b/syslogd/Makemodule.am @@ -1,3 +1,4 @@ +if USYSLOGD usyslogd_SOURCES = syslogd/syslogd.c syslogd/syslogd.h usyslogd_SOURCES += syslogd/proto.c syslogd/logfile.c usyslogd_CPPFLAGS = $(AM_CPPFLAGS) @@ -6,3 +7,13 @@ usyslogd_LDFLAGS = $(AM_LDFLAGS) usyslogd_LDADD = libinit.a sbin_PROGRAMS += usyslogd +endif + +if KLOGD +klogd_SOURCES = syslogd/klogd.c +klogd_CPPFLAGS = $(AM_CPPFLAGS) +klogd_CFLAGS = $(AM_CFLAGS) +klogd_LDFLAGS = $(AM_LDFLAGS) + +sbin_PROGRAMS += klogd +endif diff --git a/syslogd/klogd.c b/syslogd/klogd.c new file mode 100644 index 0000000..ca16e4e --- /dev/null +++ b/syslogd/klogd.c @@ -0,0 +1,191 @@ +/* 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 <https://www.gnu.org/licenses/>. + */ +#include <sys/klog.h> +#include <syslog.h> +#include <signal.h> +#include <string.h> +#include <stdlib.h> +#include <getopt.h> +#include <stdio.h> +#include <errno.h> + +#include "config.h" + +enum { + KLOG_CLOSE = 0, + KLOG_OPEN = 1, + KLOG_READ = 2, + KLOG_CONSOLE_OFF = 6, + KLOG_CONSOLE_ON = 7, + KLOG_CONSOLE_LEVEL = 8, +}; + +static char log_buffer[4096]; +static sig_atomic_t running = 1; +static int level = 0; + +static const struct option options[] = { + { "help", no_argument, NULL, 'h' }, + { "version", no_argument, NULL, 'V' }, + { "level", required_argument, NULL, 'l' }, + { NULL, 0, NULL, 0 }, +}; + +static const char *shortopt = "hVl:"; + +static const char *versiontext = +"klogd (Pygos init) "PACKAGE_VERSION"\n" +"Copyright (C) 2018 David Oberhollenzer\n" +"License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.\n" +"This is free software: you are free to change and redistribute it.\n" +"There is NO WARRANTY, to the extent permitted by law.\n"; + +static const char *helptext = +"Usage: klogd [OPTION]... \n\n" +"Collect printk() messages from the kernel and forward them to syslogd.\n" +"\n" +"The following OPTIONSs can be used:\n" +" -l, --level <level> Minimum log level that should be printed to console.\n" +" If not set, logging to console is turned off.\n" +" -h, --help Print this help text and exit\n" +" -V, --version Print version information and exit\n\n"; + +static void process_options(int argc, char **argv) +{ + int c; + + for (;;) { + c = getopt_long(argc, argv, shortopt, options, NULL); + if (c == -1) + break; + + switch (c) { + case 'l': + level = strtoul(optarg, NULL, 10); + break; + case 'h': + fputs(helptext, stdout); + exit(EXIT_SUCCESS); + case 'V': + fputs(versiontext, stdout); + exit(EXIT_SUCCESS); + default: + fputs("Try `klogd --help' for more information\n", + stderr); + exit(EXIT_FAILURE); + } + } +} + +static void sighandler(int signo) +{ + if (signo == SIGTERM || signo == SIGINT) + running = 0; +} + +static void sigsetup(void) +{ + struct sigaction act; + sigset_t mask; + + memset(&act, 0, sizeof(act)); + act.sa_handler = sighandler; + sigaction(SIGTERM, &act, NULL); + sigaction(SIGINT, &act, NULL); + + sigfillset(&mask); + sigdelset(&mask, SIGTERM); + sigdelset(&mask, SIGINT); + sigprocmask(SIG_SETMASK, &mask, NULL); +} + +static void log_open(void) +{ + klogctl(KLOG_OPEN, NULL, 0); + + if (level) { + klogctl(KLOG_CONSOLE_LEVEL, NULL, level); + } else { + klogctl(KLOG_CONSOLE_OFF, NULL, 0); + } + + openlog("kernel", 0, LOG_KERN); +} + +static void log_close(void) +{ + klogctl(KLOG_CONSOLE_ON, NULL, 0); + klogctl(KLOG_CLOSE, NULL, 0); + syslog(LOG_NOTICE, "-- klogd terminating --"); +} + +int main(int argc, char **argv) +{ + int diff, count = 0, priority, ret = EXIT_SUCCESS; + char *ptr, *end; + + process_options(argc, argv); + sigsetup(); + log_open(); + + /* TODO: seccomp lockdown? */ + + while (running) { + diff = klogctl(KLOG_READ, log_buffer + count, + sizeof(log_buffer) - 1 - count); + + if (diff < 0) { + if (errno == EINTR) + continue; + syslog(LOG_CRIT, "klogctl read: %s", strerror(errno)); + ret = EXIT_FAILURE; + break; + } + + count += diff; + log_buffer[count] = '\0'; + ptr = log_buffer; + + for (;;) { + end = strchr(ptr, '\n'); + if (end == NULL) { + count = strlen(ptr); + memmove(log_buffer, ptr, count); + break; + } + + *(end++) = '\0'; + priority = LOG_INFO; + + if (*ptr == '<') { + ++ptr; + if (*ptr) + priority = strtoul(ptr, &ptr, 10); + if (*ptr == '>') + ++ptr; + } + + if (*ptr) + syslog(priority, "%s", ptr); + ptr = end; + } + } + + log_close(); + return ret; +} |