MEDIUM: log: support a user-configurable max log line length
With all the goodies supported by logformat, people find that the limit
of 1024 chars for log lines is too short. Some servers do not support
larger lines and can simply drop them, so changing the default value is
not always the best choice.
This patch takes a different approach. Log line length is specified per
log server on the "log" line, with a value between 80 and 65535. That
way it's possibly to satisfy all needs, even with some fat local servers
and small remote ones.
(cherry picked from commit 18324f574f349d510622ff45635de899437a3a11)
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 080d8fc..e53bb21 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -559,7 +559,7 @@
Similar to "gid" but uses the GID of group name <group name> from /etc/group.
See also "gid" and "user".
-log <address> <facility> [max level [min level]]
+log <address> [len <length>] <facility> [max level [min level]]
Adds a global syslog server. Up to two global servers can be defined. They
will receive logs for startups and exits, as well as all logs from proxies
configured with "log global".
@@ -584,6 +584,18 @@
optionally enclosing them with braces ('{}'), similarly to what is done
in Bourne shell.
+ <length> is an optional maximum line length. Log lines larger than this value
+ will be truncated before being sent. The reason is that syslog
+ servers act differently on log line length. All servers support the
+ default value of 1024, but some servers simply drop larger lines
+ while others do log them. If a server supports long lines, it may
+ make sense to set this value here in order to avoid truncating long
+ lines. Similarly, if a server drops long lines, it is preferable to
+ truncate them before sending them. Accepted values are 80 to 65535
+ inclusive. The default value of 1024 is generally fine for all
+ standard usages. Some specific cases of long captures or
+ JSON-formated logs may require larger values.
+
<facility> must be one of the 24 standard syslog facilities :
kern user mail daemon auth syslog lpr news
@@ -3349,7 +3361,7 @@
log global
-log <address> <facility> [<level> [<minlevel>]]
+log <address> [len <length>] <facility> [<level> [<minlevel>]]
no log
Enable per-instance logging of events and traffic.
May be used in sections : defaults | frontend | listen | backend
@@ -3389,6 +3401,18 @@
sign ('$') and optionally enclosing them with braces ('{}'),
similarly to what is done in Bourne shell.
+ <length> is an optional maximum line length. Log lines larger than this
+ value will be truncated before being sent. The reason is that
+ syslog servers act differently on log line length. All servers
+ support the default value of 1024, but some servers simply drop
+ larger lines while others do log them. If a server supports long
+ lines, it may make sense to set this value here in order to avoid
+ truncating long lines. Similarly, if a server drops long lines,
+ it is preferable to truncate them before sending them. Accepted
+ values are 80 to 65535 inclusive. The default value of 1024 is
+ generally fine for all standard usages. Some specific cases of
+ long captures or JSON-formated logs may require larger values.
+
<facility> must be one of the 24 standard syslog facilities :
kern user mail daemon auth syslog lpr news
diff --git a/include/proto/log.h b/include/proto/log.h
index e3c1a75..54c51d1 100644
--- a/include/proto/log.h
+++ b/include/proto/log.h
@@ -39,6 +39,7 @@
extern char default_tcp_log_format[];
extern char default_http_log_format[];
extern char clf_http_log_format[];
+extern char *logline;
int build_logline(struct session *s, char *dst, size_t maxsize, struct list *list_format);
diff --git a/include/types/global.h b/include/types/global.h
index 23e3f3d..77df1dd 100644
--- a/include/types/global.h
+++ b/include/types/global.h
@@ -110,6 +110,7 @@
int last_checks;
int spread_checks;
int max_spread_checks;
+ int max_syslog_len;
char *chroot;
char *pidfile;
char *node, *desc; /* node name & description */
diff --git a/include/types/log.h b/include/types/log.h
index b3288bd..c7e47ea 100644
--- a/include/types/log.h
+++ b/include/types/log.h
@@ -152,6 +152,7 @@
int facility;
int level;
int minlvl;
+ int maxlen;
};
#endif /* _TYPES_LOG_H */
diff --git a/src/cfgparse.c b/src/cfgparse.c
index 762978a..e6e65b4 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -1254,6 +1254,8 @@
struct sockaddr_storage *sk;
int port1, port2;
struct logsrv *logsrv;
+ int arg = 0;
+ int len = 0;
if (*(args[1]) == 0 || *(args[2]) == 0) {
Alert("parsing [%s:%d] : '%s' expects <address> and <facility> as arguments.\n", file, linenum, args[0]);
@@ -1263,28 +1265,50 @@
logsrv = calloc(1, sizeof(struct logsrv));
- logsrv->facility = get_log_facility(args[2]);
+ /* just after the address, a length may be specified */
+ if (strcmp(args[arg+2], "len") == 0) {
+ len = atoi(args[arg+3]);
+ if (len < 80 || len > 65535) {
+ Alert("parsing [%s:%d] : invalid log length '%s', must be between 80 and 65535.\n",
+ file, linenum, args[arg+3]);
+ err_code |= ERR_ALERT | ERR_FATAL;
+ goto out;
+ }
+ logsrv->maxlen = len;
+
+ /* skip these two args */
+ arg += 2;
+ }
+ else
+ logsrv->maxlen = MAX_SYSLOG_LEN;
+
+ if (logsrv->maxlen > global.max_syslog_len) {
+ global.max_syslog_len = logsrv->maxlen;
+ logline = realloc(logline, global.max_syslog_len + 1);
+ }
+
+ logsrv->facility = get_log_facility(args[arg+2]);
if (logsrv->facility < 0) {
- Alert("parsing [%s:%d] : unknown log facility '%s'\n", file, linenum, args[2]);
+ Alert("parsing [%s:%d] : unknown log facility '%s'\n", file, linenum, args[arg+2]);
err_code |= ERR_ALERT | ERR_FATAL;
logsrv->facility = 0;
}
logsrv->level = 7; /* max syslog level = debug */
- if (*(args[3])) {
- logsrv->level = get_log_level(args[3]);
+ if (*(args[arg+3])) {
+ logsrv->level = get_log_level(args[arg+3]);
if (logsrv->level < 0) {
- Alert("parsing [%s:%d] : unknown optional log level '%s'\n", file, linenum, args[3]);
+ Alert("parsing [%s:%d] : unknown optional log level '%s'\n", file, linenum, args[arg+3]);
err_code |= ERR_ALERT | ERR_FATAL;
logsrv->level = 0;
}
}
logsrv->minlvl = 0; /* limit syslog level to this level (emerg) */
- if (*(args[4])) {
- logsrv->minlvl = get_log_level(args[4]);
+ if (*(args[arg+4])) {
+ logsrv->minlvl = get_log_level(args[arg+4]);
if (logsrv->minlvl < 0) {
- Alert("parsing [%s:%d] : unknown optional minimum log level '%s'\n", file, linenum, args[4]);
+ Alert("parsing [%s:%d] : unknown optional minimum log level '%s'\n", file, linenum, args[arg+4]);
err_code |= ERR_ALERT | ERR_FATAL;
logsrv->minlvl = 0;
}
@@ -4791,22 +4815,46 @@
else if (*(args[1]) && *(args[2])) {
struct sockaddr_storage *sk;
int port1, port2;
+ int arg = 0;
+ int len = 0;
logsrv = calloc(1, sizeof(struct logsrv));
- logsrv->facility = get_log_facility(args[2]);
+ /* just after the address, a length may be specified */
+ if (strcmp(args[arg+2], "len") == 0) {
+ len = atoi(args[arg+3]);
+ if (len < 80 || len > 65535) {
+ Alert("parsing [%s:%d] : invalid log length '%s', must be between 80 and 65535.\n",
+ file, linenum, args[arg+3]);
+ err_code |= ERR_ALERT | ERR_FATAL;
+ goto out;
+ }
+ logsrv->maxlen = len;
+
+ /* skip these two args */
+ arg += 2;
+ }
+ else
+ logsrv->maxlen = MAX_SYSLOG_LEN;
+
+ if (logsrv->maxlen > global.max_syslog_len) {
+ global.max_syslog_len = logsrv->maxlen;
+ logline = realloc(logline, global.max_syslog_len + 1);
+ }
+
+ logsrv->facility = get_log_facility(args[arg+2]);
if (logsrv->facility < 0) {
- Alert("parsing [%s:%d] : unknown log facility '%s'\n", file, linenum, args[2]);
+ Alert("parsing [%s:%d] : unknown log facility '%s'\n", file, linenum, args[arg+2]);
err_code |= ERR_ALERT | ERR_FATAL;
goto out;
}
logsrv->level = 7; /* max syslog level = debug */
- if (*(args[3])) {
- logsrv->level = get_log_level(args[3]);
+ if (*(args[arg+3])) {
+ logsrv->level = get_log_level(args[arg+3]);
if (logsrv->level < 0) {
- Alert("parsing [%s:%d] : unknown optional log level '%s'\n", file, linenum, args[3]);
+ Alert("parsing [%s:%d] : unknown optional log level '%s'\n", file, linenum, args[arg+3]);
err_code |= ERR_ALERT | ERR_FATAL;
goto out;
@@ -4814,10 +4862,10 @@
}
logsrv->minlvl = 0; /* limit syslog level to this level (emerg) */
- if (*(args[4])) {
- logsrv->minlvl = get_log_level(args[4]);
+ if (*(args[arg+4])) {
+ logsrv->minlvl = get_log_level(args[arg+4]);
if (logsrv->minlvl < 0) {
- Alert("parsing [%s:%d] : unknown optional minimum log level '%s'\n", file, linenum, args[4]);
+ Alert("parsing [%s:%d] : unknown optional minimum log level '%s'\n", file, linenum, args[arg+4]);
err_code |= ERR_ALERT | ERR_FATAL;
goto out;
diff --git a/src/log.c b/src/log.c
index 114ab7b..3e3acb4 100644
--- a/src/log.c
+++ b/src/log.c
@@ -146,7 +146,7 @@
/* This is a global syslog line, common to all outgoing messages. It begins
* with the syslog tag and the date that are updated by update_log_hdr().
*/
-static char logline[MAX_SYSLOG_LEN];
+char *logline = NULL;
struct logformat_var_args {
char *name;
@@ -736,7 +736,7 @@
tvsec = date.tv_sec;
get_localtime(tvsec, &tm);
- hdr_len = snprintf(logline, MAX_SYSLOG_LEN,
+ hdr_len = snprintf(logline, global.max_syslog_len,
"<<<<>%s %2d %02d:%02d:%02d %s%s[%d]: ",
monthname[tm.tm_mon],
tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec,
@@ -746,8 +746,8 @@
* either -1 or the number of bytes that would be needed to store
* the total message. In both cases, we must adjust it.
*/
- if (hdr_len < 0 || hdr_len > MAX_SYSLOG_LEN)
- hdr_len = MAX_SYSLOG_LEN;
+ if (hdr_len < 0 || hdr_len > global.max_syslog_len)
+ hdr_len = global.max_syslog_len;
dataptr = logline + hdr_len;
}
@@ -772,9 +772,9 @@
data_len = dataptr - logline;
va_start(argp, format);
- data_len += vsnprintf(dataptr, logline + sizeof(logline) - dataptr, format, argp);
- if (data_len < 0 || data_len > MAX_SYSLOG_LEN)
- data_len = MAX_SYSLOG_LEN;
+ data_len += vsnprintf(dataptr, logline + global.max_syslog_len - dataptr, format, argp);
+ if (data_len < 0 || data_len > global.max_syslog_len)
+ data_len = global.max_syslog_len;
va_end(argp);
__send_log(p, level, logline, data_len);
@@ -811,8 +811,6 @@
if (!logsrvs)
return;
- message[size - 1] = '\n';
-
/* Send log messages to syslog server. */
nblogger = 0;
list_for_each_entry(tmp, logsrvs, list) {
@@ -820,6 +818,8 @@
int *plogfd = logsrv->addr.ss_family == AF_UNIX ?
&logfdunix : &logfdinet;
int sent;
+ int max;
+ char backup;
nblogger++;
@@ -858,9 +858,23 @@
} while (fac_level && log_ptr > dataptr);
*log_ptr = '<';
+ max = size - (log_ptr - dataptr);
+ if (max > logsrv->maxlen)
+ max = logsrv->maxlen;
+
+ /* insert a \n at the end of the message, but save what was
+ * there first because we could have different max lengths
+ * for different log targets.
+ */
+ backup = log_ptr[max - 1];
+ log_ptr[max - 1] = '\n';
+
- sent = sendto(*plogfd, log_ptr, size - (log_ptr - dataptr),
+ sent = sendto(*plogfd, log_ptr, max,
MSG_DONTWAIT | MSG_NOSIGNAL,
(struct sockaddr *)&logsrv->addr, get_addr_len(&logsrv->addr));
+
+ log_ptr[max - 1] = backup;
+
if (sent < 0) {
Alert("sendto logger #%d failed: %s (errno=%d)\n",
nblogger, strerror(errno), errno);
@@ -1604,7 +1618,7 @@
tmplog = update_log_hdr();
size = tmplog - logline;
- size += build_logline(s, tmplog, sizeof(logline) - size, &s->fe->logformat);
+ size += build_logline(s, tmplog, global.max_syslog_len - size, &s->fe->logformat);
if (size > 0) {
__send_log(s->fe, level, logline, size + 1);
s->logs.logwait = 0;