Add syslog_pid sudoers option to log sudo's process ID when logging

via syslog.  This is disabled by default to match historic behavior.

plugins/sudoers/def_data.c

@@ -465,6 +465,10 @@ struct sudo_defs_types sudo_defs_table[] = {
 	"iolog_flush", T_FLAG,
 	N_("Flush I/O log data to disk immediately instead of buffering it"),
 	NULL,
+    }, {
+	"syslog_pid", T_FLAG,
+	N_("Include the process ID when logging via syslog"),
+	NULL,
     }, {
 	NULL, 0, NULL
     }

plugins/sudoers/def_data.h

@@ -216,6 +216,8 @@
 #define def_user_command_timeouts (sudo_defs_table[I_USER_COMMAND_TIMEOUTS].sd_un.flag)
 #define I_IOLOG_FLUSH           108
 #define def_iolog_flush         (sudo_defs_table[I_IOLOG_FLUSH].sd_un.flag)
+#define I_SYSLOG_PID            109
+#define def_syslog_pid          (sudo_defs_table[I_SYSLOG_PID].sd_un.flag)
 
 enum def_tuple {
 	never,

plugins/sudoers/def_data.in

@@ -341,3 +341,6 @@ user_command_timeouts
 iolog_flush
 	T_FLAG
 	"Flush I/O log data to disk immediately instead of buffering it"
+syslog_pid
+	T_FLAG
+	"Include the process ID when logging via syslog"

plugins/sudoers/logging.c

@@ -70,10 +70,11 @@ static char *new_logline(const char *, int);
 static void
 mysyslog(int pri, const char *fmt, ...)
 {
+    const int flags = def_syslog_pid ? LOG_PID : 0;
     va_list ap;
     debug_decl(mysyslog, SUDOERS_DEBUG_LOGGING)
 
-    openlog("sudo", 0, def_syslog);
+    openlog("sudo", flags, def_syslog);
     va_start(ap, fmt);
     vsyslog(pri, fmt, ap);
     va_end(ap);