drivers/syslog: Add RFC 5424 protocol support

Initial implementation of RFC 5424 support (syslog protocol). Allows
users to force-format the syslog output in a RFC 5424 compatible way,
making NuttX systems 'originators' that are able to interface with
syslog 'collectors' and 'relays' (useful for logging to syslog servers).

In addition to regular formatting options for syslog output, users can
also add structured data (currently only timeQuality is implemented,
assuming no sync and no timezone is no known). Facilities and severities
now also follow RFC 5424. Support for additional features (like
more sdata elements, msgid, etc.) will need to be built into the syslog
implementation if desired.
This commit is contained in:
Matteo Golin 2025-06-07 23:51:56 -04:00 committed by Xiang Xiao
parent cf1e92e5a2
commit 4ccc3d4c96
7 changed files with 334 additions and 42 deletions

View file

@ -25,7 +25,14 @@
set(SRCS)
if(CONFIG_SYSLOG)
list(APPEND SRCS vsyslog.c syslog_channel.c syslog_write.c syslog_flush.c)
if(CONFIG_SYSLOG_RFC5424)
list(APPEND SRCS vsyslog_rfc5424.c)
else()
list(APPEND SRCS vsyslog.c)
endif()
list(APPEND SRCS syslog_channel.c syslog_write.c syslog_flush.c)
endif()
if(CONFIG_SYSLOG_INTBUFFER)

View file

@ -140,11 +140,39 @@ config SYSLOG_INTBUFSIZE
comment "Formatting options"
config SYSLOG_TIMESTAMP
bool "Prepend timestamp to syslog message"
config SYSLOG_RFC5424
bool "Standard syslog format (RFC 5424)"
default n
---help---
Prepend timestamp to syslog message.
Forces syslog logs to follow the RFC 5424 (syslog protocol) standard.
This allows for structured data elements, standard severity levels,
standard facilities, standard timestamps and other features that allow
syslogs to be compatible with other open source programs (such as
logging servers).
if SYSLOG_RFC5424
comment "RFC5424 options"
config SYSLOG_RFC5424_HOSTNAME
bool "Enable hostname field"
default n
---help---
Adds the HOSTNAME field to the RFC 5424 compatible syslog output.
config SYSLOG_RFC5424_TIMEQUALITY
bool "timeQuality structured data"
depends on SYSLOG_TIMESTAMP
default n
---help---
Enables the RFC 5424 'timeQuality' structured data element, which describes the
quality of the timestamp sent.
endif # SYSLOG_RFC5424
if !SYSLOG_RFC5424
comment "Regular syslog formatting options"
config SYSLOG_TIMESTAMP_REALTIME
bool "Use wall-clock for syslog timestamp"
@ -198,19 +226,6 @@ config SYSLOG_PRIORITY
---help---
Prepend log priority (severity) to syslog message.
config SYSLOG_PROCESS_NAME
bool "Prepend process name to syslog message"
default n
depends on TASK_NAME_SIZE > 0
---help---
Prepend Process name to syslog message.
config SYSLOG_PROCESSID
bool "Prepend process ID to syslog message"
default n
---help---
Prepend Process ID to syslog message.
config SYSLOG_PREFIX
bool "Prepend prefix to syslog message"
default n
@ -229,6 +244,28 @@ config SYSLOG_COLOR_OUTPUT
---help---
Enables colored output in syslog, according to message priority.
endif # !SYSLOG_RFC5424
config SYSLOG_TIMESTAMP
bool "Timestamp in syslog message"
default n
---help---
Prepend timestamp to syslog message, or include the TIMESTAMP field for
RFC 5424.
config SYSLOG_PROCESS_NAME
bool "Prepend process name to syslog message"
default n
depends on TASK_NAME_SIZE > 0
---help---
Prepend Process name to syslog message.
config SYSLOG_PROCESSID
bool "Prepend process ID to syslog message"
default n
---help---
Prepend Process ID to syslog message.
comment "SYSLOG channels"
config SYSLOG_DEVPATH

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@ -24,8 +24,14 @@
# Include SYSLOG Infrastructure
ifeq ($(CONFIG_SYSLOG),y)
CSRCS += vsyslog.c syslog_channel.c
CSRCS += syslog_write.c syslog_flush.c
ifeq ($(CONFIG_SYSLOG_RFC5424),y)
CSRCS += vsyslog_rfc5424.c
else
CSRCS += vsyslog.c
endif
CSRCS += syslog_channel.c syslog_write.c syslog_flush.c
endif
ifeq ($(CONFIG_SYSLOG_INTBUFFER),y)

View file

@ -229,13 +229,13 @@ int nx_vsyslog(int priority, FAR const IPTR char *fmt, FAR va_list *ap)
#if defined(CONFIG_SYSLOG_COLOR_OUTPUT)
/* Set the terminal style according to message priority. */
, g_priority_color[priority]
, g_priority_color[LOG_PRI(priority)]
#endif
#if defined(CONFIG_SYSLOG_PRIORITY)
/* Prepend the message priority. */
, g_priority_str[priority]
, g_priority_str[LOG_PRI(priority)]
#endif
#if defined(CONFIG_SYSLOG_PREFIX)

View file

@ -0,0 +1,238 @@
/****************************************************************************
* drivers/syslog/vsyslog_rfc5424.c
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <errno.h>
#include <stdio.h>
#include <syslog.h>
#include <nuttx/arch.h>
#include <nuttx/clock.h>
#include <nuttx/init.h>
#include <nuttx/streams.h>
#include <nuttx/syslog/syslog.h>
#include "syslog.h"
/****************************************************************************
* Preprocessor definitions
****************************************************************************/
/* RFC5424 NILVALUE encoding */
#define NILVALUE "-"
#define NILVALUE_SPACE NILVALUE " "
/* RFC5424 timestamp format string (fractional seconds and 'Z' added by
* appending to format string)
*/
#define RFC5424_STRFTIME "%Y-%m-%dT%H:%M:%S"
/* RFC5424 structured data options were selected */
#ifdef CONFIG_SYSLOG_RFC5424_TIMEQUALITY
# define HAVE_RFC5424_SDATA 1
#else
# define HAVE_RFC5424_SDATA 0
#endif /* defined(CONFIG_SYSLOG_RFC5424_TIMEQUALITY) || ... */
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nx_vsyslog
*
* Description:
* nx_vsyslog() handles the system logging system calls. It is functionally
* equivalent to vsyslog() except that (1) the per-process priority
* filtering has already been performed and the va_list parameter is
* passed by reference. That is because the va_list is a structure in
* some compilers and passing of structures in the NuttX sycalls does
* not work.
*
****************************************************************************/
int nx_vsyslog(int priority, FAR const IPTR char *fmt, FAR va_list *ap)
{
struct lib_syslograwstream_s stream;
int ret = 0;
#ifdef CONFIG_SYSLOG_PROCESS_NAME
FAR struct tcb_s *tcb = nxsched_self();
#endif
#ifdef CONFIG_SYSLOG_TIMESTAMP
struct timespec ts =
{
0
};
struct tm tm =
{
0
};
char date_buf[64];
#endif
#ifdef CONFIG_SYSLOG_RFC5424_HOSTNAME
char hostname_buf[HOST_NAME_MAX + 1];
#endif
/* Wrap the low-level output in a stream object and let lib_vsprintf
* do the work.
*/
lib_syslograwstream_open(&stream);
#ifdef CONFIG_SYSLOG_TIMESTAMP
/* Get the current time. Since debug output may be generated very early
* in the start-up sequence, hardware timer support may not yet be
* available.
*/
if (OSINIT_HW_READY())
{
/* Use CLOCK_REALTIME if so configured */
clock_gettime(CLOCK_REALTIME, &ts);
/* Prepend the message with the current time, if available */
gmtime_r(&ts.tv_sec, &tm);
}
/* RFC 5424 compatible syslog output, use the required format string */
strftime(date_buf, sizeof(date_buf), RFC5424_STRFTIME, &tm);
#endif /* CONFIG_SYSLOG_TIMESTAMP */
/* Get the host name string. NuttX configures this to be empty by default,
* so if there is just an empty string, we'll set it to the NILVALUE to
* stay within RFC 5424 spec.
*/
#ifdef CONFIG_SYSLOG_RFC5424_HOSTNAME
gethostname(hostname_buf, sizeof(hostname_buf));
if (hostname_buf[0] == '\0')
{
memcpy(hostname_buf, NILVALUE, sizeof(NILVALUE));
}
#endif
/* Output the RFC5424 header */
ret = lib_sprintf_internal(&stream.common,
/* Start of format string */
"<%d>" /* PRI */
"1 " /* VERSION */
/* End of format string */
#ifdef CONFIG_SYSLOG_TIMESTAMP
"%s.%06ldZ " /* TIMESTAMP */
#else
NILVALUE_SPACE /* NO TIMESTAMP */
#endif
#ifdef CONFIG_SYSLOG_RFC5424_HOSTNAME
"%s " /* HOSTNAME */
#else
NILVALUE_SPACE /* NO HOSTNAME */
#endif
#ifdef CONFIG_SYSLOG_PROCESS_NAME
"%s " /* APPNAME */
#else
NILVALUE_SPACE /* NO APPNAME */
#endif
#ifdef CONFIG_SYSLOG_PROCESSID
"%d " /* PROCID */
#else
NILVALUE_SPACE /* NO PROCID */
#endif
NILVALUE_SPACE /* TODO: MSGID */
#if !HAVE_RFC5424_SDATA
NILVALUE_SPACE /* Empty structured data, print the NILVALUE here to
* save `libsprintf` call */
#endif
#ifdef CONFIG_SYSLOG_RFC5424_TIMEQUALITY
"[timeQuality isSynced=\"%d\" tzKnown=\"%d\"]"
#endif
#if HAVE_RFC5424_SDATA
" " /* Space at the end of structured data before message */
#endif
/* Beginning of formatted arguments */
, priority /* PRIVAL */
#ifdef CONFIG_SYSLOG_TIMESTAMP
, date_buf, ts.tv_nsec / NSEC_PER_USEC /* TIMESTAMP */
#endif
#ifdef CONFIG_SYSLOG_RFC5424_HOSTNAME
, hostname_buf /* HOSTNAME */
#endif
#ifdef CONFIG_SYSLOG_PROCESS_NAME
, get_task_name(tcb)
#endif
#ifdef CONFIG_SYSLOG_PROCESSID
, nxsched_gettid() /* PROCID */
#endif
/* TODO: MSGID */
/* Formatted arguments for structured data */
#ifdef CONFIG_SYSLOG_RFC5424_TIMEQUALITY
, 0 /* TODO: Not sure if synced */
, 0 /* TODO: Not sure if time zone known */
#endif
/* End of formatted arguments */
);
/* MSG string is generated below from common code for all syslog
* calls since RFC5424 allows the MSG field to be a free-form string.
*/
/* Generate the output */
ret += lib_vsprintf_internal(&stream.common, fmt, *ap);
if (stream.last_ch != '\n')
{
lib_stream_putc(&stream.common, '\n');
ret++;
}
/* Flush and destroy the syslog stream buffer */
lib_syslograwstream_close(&stream);
return ret;
}

View file

@ -87,26 +87,26 @@
* LOG_UUCP - UUCP subsystem
*/
#define LOG_AUTH 0
#define LOG_AUTHPRIV 0
#define LOG_CRON 0
#define LOG_DAEMON 0
#define LOG_FTP 0
#define LOG_KERN 0
#define LOG_LOCAL0 0
#define LOG_LOCAL1 0
#define LOG_LOCAL2 0
#define LOG_LOCAL3 0
#define LOG_LOCAL4 0
#define LOG_LOCAL5 0
#define LOG_LOCAL6 0
#define LOG_LOCAL7 0
#define LOG_LPR 0
#define LOG_MAIL 0
#define LOG_NEWS 0
#define LOG_SYSLOG 0
#define LOG_USER 0
#define LOG_UUCP 0
#define LOG_KERN (0 << 3)
#define LOG_USER (1 << 3)
#define LOG_MAIL (2 << 3)
#define LOG_DAEMON (3 << 3)
#define LOG_AUTH (4 << 3)
#define LOG_SYSLOG (5 << 3)
#define LOG_LPR (6 << 3)
#define LOG_NEWS (7 << 3)
#define LOG_UUCP (8 << 3)
#define LOG_CRON (9 << 3)
#define LOG_AUTHPRIV (10 << 3)
#define LOG_FTP (11 << 3)
#define LOG_LOCAL0 (16 << 3)
#define LOG_LOCAL1 (17 << 3)
#define LOG_LOCAL2 (18 << 3)
#define LOG_LOCAL3 (19 << 3)
#define LOG_LOCAL4 (20 << 3)
#define LOG_LOCAL5 (21 << 3)
#define LOG_LOCAL6 (22 << 3)
#define LOG_LOCAL7 (23 << 3)
/* This determines the importance of the message. The levels are, in order
* of decreasing importance:
@ -127,6 +127,10 @@
#define LOG_UPTO(p) ((1 << ((p)+1)) - 1)
#define LOG_ALL 0xff
#define LOG_PRIMASK 0x07 /* mask to extract priority part (internal) */
#define LOG_PRI(p) ((p) & LOG_PRIMASK) /* extract priority */
#define LOG_MAKEPRI(fac, pri) ((fac) | (pri))
/****************************************************************************
* Public Function Prototypes
****************************************************************************/

View file

@ -54,7 +54,7 @@ void vsyslog(int priority, FAR const IPTR char *fmt, va_list ap)
{
/* Check if this priority is enabled */
if ((g_syslog_mask & LOG_MASK(priority)) != 0)
if ((g_syslog_mask & LOG_MASK(LOG_PRI(priority))) != 0)
{
/* Yes.. Perform the nx_vsyslog system call.
*