tor/src/common/log.c

1540 lines
43 KiB
C

/* Copyright (c) 2001, Matej Pfajfar.
* Copyright (c) 2001-2004, Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2017, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file log.c
* \brief Functions to send messages to log files or the console.
**/
#include "orconfig.h"
#include <stdarg.h>
#include <assert.h>
// #include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#include "compat.h"
#include "util.h"
#define LOG_PRIVATE
#include "torlog.h"
#include "container.h"
#ifdef HAVE_ANDROID_LOG_H
#include <android/log.h>
#endif // HAVE_ANDROID_LOG_H.
/** Given a severity, yields an index into log_severity_list_t.masks to use
* for that severity. */
#define SEVERITY_MASK_IDX(sev) ((sev) - LOG_ERR)
/** @{ */
/** The string we stick at the end of a log message when it is too long,
* and its length. */
#define TRUNCATED_STR "[...truncated]"
#define TRUNCATED_STR_LEN 14
/** @} */
#define raw_assert(x) assert(x) // assert OK
/** Defining compile-time constants for Tor log levels (used by the Rust
* log wrapper at src/rust/tor_log) */
const int LOG_WARN_ = LOG_WARN;
const int LOG_NOTICE_ = LOG_NOTICE;
const log_domain_mask_t LD_GENERAL_ = LD_GENERAL;
const log_domain_mask_t LD_NET_ = LD_NET;
/** Information for a single logfile; only used in log.c */
typedef struct logfile_t {
struct logfile_t *next; /**< Next logfile_t in the linked list. */
char *filename; /**< Filename to open. */
int fd; /**< fd to receive log messages, or -1 for none. */
int seems_dead; /**< Boolean: true if the stream seems to be kaput. */
int needs_close; /**< Boolean: true if the stream gets closed on shutdown. */
int is_temporary; /**< Boolean: close after initializing logging subsystem.*/
int is_syslog; /**< Boolean: send messages to syslog. */
int is_android; /**< Boolean: send messages to Android's log subsystem. */
char *android_tag; /**< Identity Tag used in Android's log subsystem. */
log_callback callback; /**< If not NULL, send messages to this function. */
log_severity_list_t *severities; /**< Which severity of messages should we
* log for each log domain? */
} logfile_t;
static void log_free_(logfile_t *victim);
#define log_free(lg) \
FREE_AND_NULL(logfile_t, log_free_, (lg))
/** Helper: map a log severity to descriptive string. */
static inline const char *
sev_to_string(int severity)
{
switch (severity) {
case LOG_DEBUG: return "debug";
case LOG_INFO: return "info";
case LOG_NOTICE: return "notice";
case LOG_WARN: return "warn";
case LOG_ERR: return "err";
default: /* Call assert, not tor_assert, since tor_assert
* calls log on failure. */
raw_assert(0); return "UNKNOWN"; // LCOV_EXCL_LINE
}
}
/** Helper: decide whether to include the function name in the log message. */
static inline int
should_log_function_name(log_domain_mask_t domain, int severity)
{
switch (severity) {
case LOG_DEBUG:
case LOG_INFO:
/* All debugging messages occur in interesting places. */
return (domain & LD_NOFUNCNAME) == 0;
case LOG_NOTICE:
case LOG_WARN:
case LOG_ERR:
/* We care about places where bugs occur. */
return (domain & (LD_BUG|LD_NOFUNCNAME)) == LD_BUG;
default:
/* Call assert, not tor_assert, since tor_assert calls log on failure. */
raw_assert(0); return 0; // LCOV_EXCL_LINE
}
}
#ifdef HAVE_ANDROID_LOG_H
/** Helper function to convert Tor's log severity into the matching
* Android log priority.
*/
static int
severity_to_android_log_priority(int severity)
{
switch (severity) {
case LOG_DEBUG:
return ANDROID_LOG_VERBOSE;
case LOG_INFO:
return ANDROID_LOG_DEBUG;
case LOG_NOTICE:
return ANDROID_LOG_INFO;
case LOG_WARN:
return ANDROID_LOG_WARN;
case LOG_ERR:
return ANDROID_LOG_ERROR;
default:
// LCOV_EXCL_START
raw_assert(0);
return 0;
// LCOV_EXCL_STOP
}
}
#endif // HAVE_ANDROID_LOG_H.
/** A mutex to guard changes to logfiles and logging. */
static tor_mutex_t log_mutex;
/** True iff we have initialized log_mutex */
static int log_mutex_initialized = 0;
/** Linked list of logfile_t. */
static logfile_t *logfiles = NULL;
/** Boolean: do we report logging domains? */
static int log_domains_are_logged = 0;
#ifdef HAVE_SYSLOG_H
/** The number of open syslog log handlers that we have. When this reaches 0,
* we can close our connection to the syslog facility. */
static int syslog_count = 0;
#endif
/** Represents a log message that we are going to send to callback-driven
* loggers once we can do so in a non-reentrant way. */
typedef struct pending_log_message_t {
int severity; /**< The severity of the message */
log_domain_mask_t domain; /**< The domain of the message */
char *fullmsg; /**< The message, with all decorations */
char *msg; /**< The content of the message */
} pending_log_message_t;
/** Log messages waiting to be replayed onto callback-based logs */
static smartlist_t *pending_cb_messages = NULL;
/** Callback to invoke when pending_cb_messages becomes nonempty. */
static pending_callback_callback pending_cb_cb = NULL;
/** Log messages waiting to be replayed once the logging system is initialized.
*/
static smartlist_t *pending_startup_messages = NULL;
/** Number of bytes of messages queued in pending_startup_messages. (This is
* the length of the messages, not the number of bytes used to store
* them.) */
static size_t pending_startup_messages_len;
/** True iff we should store messages while waiting for the logs to get
* configured. */
static int queue_startup_messages = 1;
/** True iff __PRETTY_FUNCTION__ includes parenthesized arguments. */
static int pretty_fn_has_parens = 0;
/** Don't store more than this many bytes of messages while waiting for the
* logs to get configured. */
#define MAX_STARTUP_MSG_LEN (1<<16)
/** Lock the log_mutex to prevent others from changing the logfile_t list */
#define LOCK_LOGS() STMT_BEGIN \
tor_assert(log_mutex_initialized); \
tor_mutex_acquire(&log_mutex); \
STMT_END
/** Unlock the log_mutex */
#define UNLOCK_LOGS() STMT_BEGIN \
tor_assert(log_mutex_initialized); \
tor_mutex_release(&log_mutex); \
STMT_END
/** What's the lowest log level anybody cares about? Checking this lets us
* bail out early from log_debug if we aren't debugging. */
int log_global_min_severity_ = LOG_NOTICE;
static void delete_log(logfile_t *victim);
static void close_log(logfile_t *victim);
static char *domain_to_string(log_domain_mask_t domain,
char *buf, size_t buflen);
static inline char *format_msg(char *buf, size_t buf_len,
log_domain_mask_t domain, int severity, const char *funcname,
const char *suffix,
const char *format, va_list ap, size_t *msg_len_out)
CHECK_PRINTF(7,0);
/** Name of the application: used to generate the message we write at the
* start of each new log. */
static char *appname = NULL;
/** Set the "application name" for the logs to <b>name</b>: we'll use this
* name in the message we write when starting up, and at the start of each new
* log.
*
* Tor uses this string to write the version number to the log file. */
void
log_set_application_name(const char *name)
{
tor_free(appname);
appname = name ? tor_strdup(name) : NULL;
}
/** Return true if some of the running logs might be interested in a log
* message of the given severity in the given domains. If this function
* returns true, the log message might be ignored anyway, but if it returns
* false, it is definitely_ safe not to log the message. */
int
log_message_is_interesting(int severity, log_domain_mask_t domain)
{
(void) domain;
return (severity <= log_global_min_severity_);
}
/**
* As tor_log, but takes an optional function name, and does not treat its
* <b>string</b> as a printf format.
*
* For use by Rust integration.
*/
void
tor_log_string(int severity, log_domain_mask_t domain,
const char *function, const char *string)
{
log_fn_(severity, domain, function, "%s", string);
}
/** Log time granularity in milliseconds. */
static int log_time_granularity = 1;
/** Define log time granularity for all logs to be <b>granularity_msec</b>
* milliseconds. */
void
set_log_time_granularity(int granularity_msec)
{
log_time_granularity = granularity_msec;
}
/** Helper: Write the standard prefix for log lines to a
* <b>buf_len</b> character buffer in <b>buf</b>.
*/
static inline size_t
log_prefix_(char *buf, size_t buf_len, int severity)
{
time_t t;
struct timeval now;
struct tm tm;
size_t n;
int r, ms;
tor_gettimeofday(&now);
t = (time_t)now.tv_sec;
ms = (int)now.tv_usec / 1000;
if (log_time_granularity >= 1000) {
t -= t % (log_time_granularity / 1000);
ms = 0;
} else {
ms -= ((int)now.tv_usec / 1000) % log_time_granularity;
}
n = strftime(buf, buf_len, "%b %d %H:%M:%S", tor_localtime_r(&t, &tm));
r = tor_snprintf(buf+n, buf_len-n, ".%.3i [%s] ", ms,
sev_to_string(severity));
if (r<0)
return buf_len-1;
else
return n+r;
}
/** If lf refers to an actual file that we have just opened, and the file
* contains no data, log an "opening new logfile" message at the top.
*
* Return -1 if the log is broken and needs to be deleted, else return 0.
*/
static int
log_tor_version(logfile_t *lf, int reset)
{
char buf[256];
size_t n;
int is_new;
if (!lf->needs_close)
/* If it doesn't get closed, it isn't really a file. */
return 0;
if (lf->is_temporary)
/* If it's temporary, it isn't really a file. */
return 0;
is_new = lf->fd >= 0 && tor_fd_getpos(lf->fd) == 0;
if (reset && !is_new)
/* We are resetting, but we aren't at the start of the file; no
* need to log again. */
return 0;
n = log_prefix_(buf, sizeof(buf), LOG_NOTICE);
if (appname) {
tor_snprintf(buf+n, sizeof(buf)-n,
"%s opening %slog file.\n", appname, is_new?"new ":"");
} else {
tor_snprintf(buf+n, sizeof(buf)-n,
"Tor %s opening %slog file.\n", VERSION, is_new?"new ":"");
}
if (write_all(lf->fd, buf, strlen(buf), 0) < 0) /* error */
return -1; /* failed */
return 0;
}
static const char bug_suffix[] = " (on Tor " VERSION
#ifndef _MSC_VER
" "
#include "micro-revision.i"
#endif
")";
/** Helper: Format a log message into a fixed-sized buffer. (This is
* factored out of <b>logv</b> so that we never format a message more
* than once.) Return a pointer to the first character of the message
* portion of the formatted string.
*/
static inline char *
format_msg(char *buf, size_t buf_len,
log_domain_mask_t domain, int severity, const char *funcname,
const char *suffix,
const char *format, va_list ap, size_t *msg_len_out)
{
size_t n;
int r;
char *end_of_prefix;
char *buf_end;
raw_assert(buf_len >= 16); /* prevent integer underflow and stupidity */
buf_len -= 2; /* subtract 2 characters so we have room for \n\0 */
buf_end = buf+buf_len; /* point *after* the last char we can write to */
n = log_prefix_(buf, buf_len, severity);
end_of_prefix = buf+n;
if (log_domains_are_logged) {
char *cp = buf+n;
if (cp == buf_end) goto format_msg_no_room_for_domains;
*cp++ = '{';
if (cp == buf_end) goto format_msg_no_room_for_domains;
cp = domain_to_string(domain, cp, (buf+buf_len-cp));
if (cp == buf_end) goto format_msg_no_room_for_domains;
*cp++ = '}';
if (cp == buf_end) goto format_msg_no_room_for_domains;
*cp++ = ' ';
if (cp == buf_end) goto format_msg_no_room_for_domains;
end_of_prefix = cp;
n = cp-buf;
format_msg_no_room_for_domains:
/* This will leave end_of_prefix and n unchanged, and thus cause
* whatever log domain string we had written to be clobbered. */
;
}
if (funcname && should_log_function_name(domain, severity)) {
r = tor_snprintf(buf+n, buf_len-n,
pretty_fn_has_parens ? "%s: " : "%s(): ",
funcname);
if (r<0)
n = strlen(buf);
else
n += r;
}
if (domain == LD_BUG && buf_len-n > 6) {
memcpy(buf+n, "Bug: ", 6);
n += 5;
}
r = tor_vsnprintf(buf+n,buf_len-n,format,ap);
if (r < 0) {
/* The message was too long; overwrite the end of the buffer with
* "[...truncated]" */
if (buf_len >= TRUNCATED_STR_LEN) {
size_t offset = buf_len-TRUNCATED_STR_LEN;
/* We have an extra 2 characters after buf_len to hold the \n\0,
* so it's safe to add 1 to the size here. */
strlcpy(buf+offset, TRUNCATED_STR, buf_len-offset+1);
}
/* Set 'n' to the end of the buffer, where we'll be writing \n\0.
* Since we already subtracted 2 from buf_len, this is safe.*/
n = buf_len;
} else {
n += r;
if (suffix) {
size_t suffix_len = strlen(suffix);
if (buf_len-n >= suffix_len) {
memcpy(buf+n, suffix, suffix_len);
n += suffix_len;
}
}
}
if (domain == LD_BUG &&
buf_len - n > strlen(bug_suffix)+1) {
memcpy(buf+n, bug_suffix, strlen(bug_suffix));
n += strlen(bug_suffix);
}
buf[n]='\n';
buf[n+1]='\0';
*msg_len_out = n+1;
return end_of_prefix;
}
/* Create a new pending_log_message_t with appropriate values */
static pending_log_message_t *
pending_log_message_new(int severity, log_domain_mask_t domain,
const char *fullmsg, const char *shortmsg)
{
pending_log_message_t *m = tor_malloc(sizeof(pending_log_message_t));
m->severity = severity;
m->domain = domain;
m->fullmsg = fullmsg ? tor_strdup(fullmsg) : NULL;
m->msg = tor_strdup(shortmsg);
return m;
}
#define pending_log_message_free(msg) \
FREE_AND_NULL(pending_log_message_t, pending_log_message_free_, (msg))
/** Release all storage held by <b>msg</b>. */
static void
pending_log_message_free_(pending_log_message_t *msg)
{
if (!msg)
return;
tor_free(msg->msg);
tor_free(msg->fullmsg);
tor_free(msg);
}
/** Helper function: returns true iff the log file, given in <b>lf</b>, is
* handled externally via the system log API, the Android logging API, or is an
* external callback function. */
static inline int
logfile_is_external(const logfile_t *lf)
{
raw_assert(lf);
return lf->is_syslog || lf->is_android || lf->callback;
}
/** Return true iff <b>lf</b> would like to receive a message with the
* specified <b>severity</b> in the specified <b>domain</b>.
*/
static inline int
logfile_wants_message(const logfile_t *lf, int severity,
log_domain_mask_t domain)
{
if (! (lf->severities->masks[SEVERITY_MASK_IDX(severity)] & domain)) {
return 0;
}
if (! (lf->fd >= 0 || logfile_is_external(lf))) {
return 0;
}
if (lf->seems_dead) {
return 0;
}
return 1;
}
/** Send a message to <b>lf</b>. The full message, with time prefix and
* severity, is in <b>buf</b>. The message itself is in
* <b>msg_after_prefix</b>. If <b>callbacks_deferred</b> points to true, then
* we already deferred this message for pending callbacks and don't need to do
* it again. Otherwise, if we need to do it, do it, and set
* <b>callbacks_deferred</b> to 1. */
static inline void
logfile_deliver(logfile_t *lf, const char *buf, size_t msg_len,
const char *msg_after_prefix, log_domain_mask_t domain,
int severity, int *callbacks_deferred)
{
if (lf->is_syslog) {
#ifdef HAVE_SYSLOG_H
#ifdef MAXLINE
/* Some syslog implementations have limits on the length of what you can
* pass them, and some very old ones do not detect overflow so well.
* Regrettably, they call their maximum line length MAXLINE. */
#if MAXLINE < 64
#warn "MAXLINE is a very low number; it might not be from syslog.h after all"
#endif
char *m = msg_after_prefix;
if (msg_len >= MAXLINE)
m = tor_strndup(msg_after_prefix, MAXLINE-1);
syslog(severity, "%s", m);
if (m != msg_after_prefix) {
tor_free(m);
}
#else /* !(defined(MAXLINE)) */
/* We have syslog but not MAXLINE. That's promising! */
syslog(severity, "%s", msg_after_prefix);
#endif /* defined(MAXLINE) */
#endif /* defined(HAVE_SYSLOG_H) */
} else if (lf->is_android) {
#ifdef HAVE_ANDROID_LOG_H
int priority = severity_to_android_log_priority(severity);
__android_log_write(priority, lf->android_tag, msg_after_prefix);
#endif // HAVE_ANDROID_LOG_H.
} else if (lf->callback) {
if (domain & LD_NOCB) {
if (!*callbacks_deferred && pending_cb_messages) {
smartlist_add(pending_cb_messages,
pending_log_message_new(severity,domain,NULL,msg_after_prefix));
*callbacks_deferred = 1;
if (smartlist_len(pending_cb_messages) == 1 && pending_cb_cb) {
pending_cb_cb();
}
}
} else {
lf->callback(severity, domain, msg_after_prefix);
}
} else {
if (write_all(lf->fd, buf, msg_len, 0) < 0) { /* error */
/* don't log the error! mark this log entry to be blown away, and
* continue. */
lf->seems_dead = 1;
}
}
}
/** Helper: sends a message to the appropriate logfiles, at loglevel
* <b>severity</b>. If provided, <b>funcname</b> is prepended to the
* message. The actual message is derived as from tor_snprintf(format,ap).
*/
MOCK_IMPL(STATIC void,
logv,(int severity, log_domain_mask_t domain, const char *funcname,
const char *suffix, const char *format, va_list ap))
{
char buf[10240];
size_t msg_len = 0;
int formatted = 0;
logfile_t *lf;
char *end_of_prefix=NULL;
int callbacks_deferred = 0;
/* Call assert, not tor_assert, since tor_assert calls log on failure. */
raw_assert(format);
/* check that severity is sane. Overrunning the masks array leads to
* interesting and hard to diagnose effects */
raw_assert(severity >= LOG_ERR && severity <= LOG_DEBUG);
/* check that we've initialised the log mutex before we try to lock it */
raw_assert(log_mutex_initialized);
LOCK_LOGS();
if ((! (domain & LD_NOCB)) && pending_cb_messages
&& smartlist_len(pending_cb_messages))
flush_pending_log_callbacks();
if (queue_startup_messages &&
pending_startup_messages_len < MAX_STARTUP_MSG_LEN) {
end_of_prefix =
format_msg(buf, sizeof(buf), domain, severity, funcname, suffix,
format, ap, &msg_len);
formatted = 1;
smartlist_add(pending_startup_messages,
pending_log_message_new(severity,domain,buf,end_of_prefix));
pending_startup_messages_len += msg_len;
}
for (lf = logfiles; lf; lf = lf->next) {
if (! logfile_wants_message(lf, severity, domain))
continue;
if (!formatted) {
end_of_prefix =
format_msg(buf, sizeof(buf), domain, severity, funcname, suffix,
format, ap, &msg_len);
formatted = 1;
}
logfile_deliver(lf, buf, msg_len, end_of_prefix, domain, severity,
&callbacks_deferred);
}
UNLOCK_LOGS();
}
/** Output a message to the log. It gets logged to all logfiles that
* care about messages with <b>severity</b> in <b>domain</b>. The content
* is formatted printf-style based on <b>format</b> and extra arguments.
* */
void
tor_log(int severity, log_domain_mask_t domain, const char *format, ...)
{
va_list ap;
if (severity > log_global_min_severity_)
return;
va_start(ap,format);
#ifdef TOR_UNIT_TESTS
if (domain & LD_NO_MOCK)
logv__real(severity, domain, NULL, NULL, format, ap);
else
#endif
logv(severity, domain, NULL, NULL, format, ap);
va_end(ap);
}
/** Maximum number of fds that will get notifications if we crash */
#define MAX_SIGSAFE_FDS 8
/** Array of fds to log crash-style warnings to. */
static int sigsafe_log_fds[MAX_SIGSAFE_FDS] = { STDERR_FILENO };
/** The number of elements used in sigsafe_log_fds */
static int n_sigsafe_log_fds = 1;
/** Write <b>s</b> to each element of sigsafe_log_fds. Return 0 on success, -1
* on failure. */
static int
tor_log_err_sigsafe_write(const char *s)
{
int i;
ssize_t r;
size_t len = strlen(s);
int err = 0;
for (i=0; i < n_sigsafe_log_fds; ++i) {
r = write(sigsafe_log_fds[i], s, len);
err += (r != (ssize_t)len);
}
return err ? -1 : 0;
}
/** Given a list of string arguments ending with a NULL, writes them
* to our logs and to stderr (if possible). This function is safe to call
* from within a signal handler. */
void
tor_log_err_sigsafe(const char *m, ...)
{
va_list ap;
const char *x;
char timebuf[33];
time_t now = time(NULL);
if (!m)
return;
if (log_time_granularity >= 2000) {
int g = log_time_granularity / 1000;
now -= now % g;
}
timebuf[0] = now < 0 ? '-' : ' ';
if (now < 0) now = -now;
timebuf[1] = '\0';
format_dec_number_sigsafe(now, timebuf+1, sizeof(timebuf)-1);
tor_log_err_sigsafe_write("\n=========================================="
"================== T=");
tor_log_err_sigsafe_write(timebuf);
tor_log_err_sigsafe_write("\n");
tor_log_err_sigsafe_write(m);
va_start(ap, m);
while ((x = va_arg(ap, const char*))) {
tor_log_err_sigsafe_write(x);
}
va_end(ap);
}
/** Set *<b>out</b> to a pointer to an array of the fds to log errors to from
* inside a signal handler. Return the number of elements in the array. */
int
tor_log_get_sigsafe_err_fds(const int **out)
{
*out = sigsafe_log_fds;
return n_sigsafe_log_fds;
}
/** Helper function; return true iff the <b>n</b>-element array <b>array</b>
* contains <b>item</b>. */
static int
int_array_contains(const int *array, int n, int item)
{
int j;
for (j = 0; j < n; ++j) {
if (array[j] == item)
return 1;
}
return 0;
}
/** Function to call whenever the list of logs changes to get ready to log
* from signal handlers. */
void
tor_log_update_sigsafe_err_fds(void)
{
const logfile_t *lf;
int found_real_stderr = 0;
LOCK_LOGS();
/* Reserve the first one for stderr. This is safe because when we daemonize,
* we dup2 /dev/null to stderr, */
sigsafe_log_fds[0] = STDERR_FILENO;
n_sigsafe_log_fds = 1;
for (lf = logfiles; lf; lf = lf->next) {
/* Don't try callback to the control port, or syslogs: We can't
* do them from a signal handler. Don't try stdout: we always do stderr.
*/
if (lf->is_temporary || logfile_is_external(lf)
|| lf->seems_dead || lf->fd < 0)
continue;
if (lf->severities->masks[SEVERITY_MASK_IDX(LOG_ERR)] &
(LD_BUG|LD_GENERAL)) {
if (lf->fd == STDERR_FILENO)
found_real_stderr = 1;
/* Avoid duplicates */
if (int_array_contains(sigsafe_log_fds, n_sigsafe_log_fds, lf->fd))
continue;
sigsafe_log_fds[n_sigsafe_log_fds++] = lf->fd;
if (n_sigsafe_log_fds == MAX_SIGSAFE_FDS)
break;
}
}
if (!found_real_stderr &&
int_array_contains(sigsafe_log_fds, n_sigsafe_log_fds, STDOUT_FILENO)) {
/* Don't use a virtual stderr when we're also logging to stdout. */
raw_assert(n_sigsafe_log_fds >= 2); /* Don't tor_assert inside log fns */
sigsafe_log_fds[0] = sigsafe_log_fds[--n_sigsafe_log_fds];
}
UNLOCK_LOGS();
}
/** Add to <b>out</b> a copy of every currently configured log file name. Used
* to enable access to these filenames with the sandbox code. */
void
tor_log_get_logfile_names(smartlist_t *out)
{
logfile_t *lf;
tor_assert(out);
LOCK_LOGS();
for (lf = logfiles; lf; lf = lf->next) {
if (lf->is_temporary || logfile_is_external(lf))
continue;
if (lf->filename == NULL)
continue;
smartlist_add_strdup(out, lf->filename);
}
UNLOCK_LOGS();
}
/** Implementation of the log_fn backend, used when we have
* variadic macros. All arguments are as for log_fn, except for
* <b>fn</b>, which is the name of the calling functions. */
void
log_fn_(int severity, log_domain_mask_t domain, const char *fn,
const char *format, ...)
{
va_list ap;
if (severity > log_global_min_severity_)
return;
va_start(ap,format);
logv(severity, domain, fn, NULL, format, ap);
va_end(ap);
}
void
log_fn_ratelim_(ratelim_t *ratelim, int severity, log_domain_mask_t domain,
const char *fn, const char *format, ...)
{
va_list ap;
char *m;
if (severity > log_global_min_severity_)
return;
m = rate_limit_log(ratelim, approx_time());
if (m == NULL)
return;
va_start(ap, format);
logv(severity, domain, fn, m, format, ap);
va_end(ap);
tor_free(m);
}
/** Free all storage held by <b>victim</b>. */
static void
log_free_(logfile_t *victim)
{
if (!victim)
return;
tor_free(victim->severities);
tor_free(victim->filename);
tor_free(victim->android_tag);
tor_free(victim);
}
/** Close all open log files, and free other static memory. */
void
logs_free_all(void)
{
logfile_t *victim, *next;
smartlist_t *messages, *messages2;
LOCK_LOGS();
next = logfiles;
logfiles = NULL;
messages = pending_cb_messages;
pending_cb_messages = NULL;
pending_cb_cb = NULL;
messages2 = pending_startup_messages;
pending_startup_messages = NULL;
UNLOCK_LOGS();
while (next) {
victim = next;
next = next->next;
close_log(victim);
log_free(victim);
}
tor_free(appname);
SMARTLIST_FOREACH(messages, pending_log_message_t *, msg, {
pending_log_message_free(msg);
});
smartlist_free(messages);
if (messages2) {
SMARTLIST_FOREACH(messages2, pending_log_message_t *, msg, {
pending_log_message_free(msg);
});
smartlist_free(messages2);
}
/* We _could_ destroy the log mutex here, but that would screw up any logs
* that happened between here and the end of execution. */
}
/** Remove and free the log entry <b>victim</b> from the linked-list
* logfiles (it is probably present, but it might not be due to thread
* racing issues). After this function is called, the caller shouldn't
* refer to <b>victim</b> anymore.
*
* Long-term, we need to do something about races in the log subsystem
* in general. See bug 222 for more details.
*/
static void
delete_log(logfile_t *victim)
{
logfile_t *tmpl;
if (victim == logfiles)
logfiles = victim->next;
else {
for (tmpl = logfiles; tmpl && tmpl->next != victim; tmpl=tmpl->next) ;
// tor_assert(tmpl);
// tor_assert(tmpl->next == victim);
if (!tmpl)
return;
tmpl->next = victim->next;
}
log_free(victim);
}
/** Helper: release system resources (but not memory) held by a single
* logfile_t. */
static void
close_log(logfile_t *victim)
{
if (victim->needs_close && victim->fd >= 0) {
close(victim->fd);
victim->fd = -1;
} else if (victim->is_syslog) {
#ifdef HAVE_SYSLOG_H
if (--syslog_count == 0) {
/* There are no other syslogs; close the logging facility. */
closelog();
}
#endif /* defined(HAVE_SYSLOG_H) */
}
}
/** Adjust a log severity configuration in <b>severity_out</b> to contain
* every domain between <b>loglevelMin</b> and <b>loglevelMax</b>, inclusive.
*/
void
set_log_severity_config(int loglevelMin, int loglevelMax,
log_severity_list_t *severity_out)
{
int i;
tor_assert(loglevelMin >= loglevelMax);
tor_assert(loglevelMin >= LOG_ERR && loglevelMin <= LOG_DEBUG);
tor_assert(loglevelMax >= LOG_ERR && loglevelMax <= LOG_DEBUG);
memset(severity_out, 0, sizeof(log_severity_list_t));
for (i = loglevelMin; i >= loglevelMax; --i) {
severity_out->masks[SEVERITY_MASK_IDX(i)] = ~0u;
}
}
/** Add a log handler named <b>name</b> to send all messages in <b>severity</b>
* to <b>fd</b>. Copies <b>severity</b>. Helper: does no locking. */
static void
add_stream_log_impl(const log_severity_list_t *severity,
const char *name, int fd)
{
logfile_t *lf;
lf = tor_malloc_zero(sizeof(logfile_t));
lf->fd = fd;
lf->filename = tor_strdup(name);
lf->severities = tor_memdup(severity, sizeof(log_severity_list_t));
lf->next = logfiles;
logfiles = lf;
log_global_min_severity_ = get_min_log_level();
}
/** Add a log handler named <b>name</b> to send all messages in <b>severity</b>
* to <b>fd</b>. Steals a reference to <b>severity</b>; the caller must
* not use it after calling this function. */
void
add_stream_log(const log_severity_list_t *severity, const char *name, int fd)
{
LOCK_LOGS();
add_stream_log_impl(severity, name, fd);
UNLOCK_LOGS();
}
/** Initialize the global logging facility */
void
init_logging(int disable_startup_queue)
{
if (!log_mutex_initialized) {
tor_mutex_init(&log_mutex);
log_mutex_initialized = 1;
}
#ifdef __GNUC__
if (strchr(__PRETTY_FUNCTION__, '(')) {
pretty_fn_has_parens = 1;
}
#endif
if (pending_cb_messages == NULL)
pending_cb_messages = smartlist_new();
if (disable_startup_queue)
queue_startup_messages = 0;
if (pending_startup_messages == NULL && queue_startup_messages) {
pending_startup_messages = smartlist_new();
}
}
/** Set whether we report logging domains as a part of our log messages.
*/
void
logs_set_domain_logging(int enabled)
{
LOCK_LOGS();
log_domains_are_logged = enabled;
UNLOCK_LOGS();
}
/** Add a log handler to receive messages during startup (before the real
* logs are initialized).
*/
void
add_temp_log(int min_severity)
{
log_severity_list_t *s = tor_malloc_zero(sizeof(log_severity_list_t));
set_log_severity_config(min_severity, LOG_ERR, s);
LOCK_LOGS();
add_stream_log_impl(s, "<temp>", fileno(stdout));
tor_free(s);
logfiles->is_temporary = 1;
UNLOCK_LOGS();
}
/**
* Register "cb" as the callback to call when there are new pending log
* callbacks to be flushed with flush_pending_log_callbacks().
*
* Note that this callback, if present, can be invoked from any thread.
*
* This callback must not log.
*
* It is intentional that this function contains the name "callback" twice: it
* sets a "callback" to be called on the condition that there is a "pending
* callback".
**/
void
logs_set_pending_callback_callback(pending_callback_callback cb)
{
pending_cb_cb = cb;
}
/**
* Add a log handler to send messages in <b>severity</b>
* to the function <b>cb</b>.
*/
int
add_callback_log(const log_severity_list_t *severity, log_callback cb)
{
logfile_t *lf;
lf = tor_malloc_zero(sizeof(logfile_t));
lf->fd = -1;
lf->severities = tor_memdup(severity, sizeof(log_severity_list_t));
lf->filename = tor_strdup("<callback>");
lf->callback = cb;
lf->next = logfiles;
LOCK_LOGS();
logfiles = lf;
log_global_min_severity_ = get_min_log_level();
UNLOCK_LOGS();
return 0;
}
/** Adjust the configured severity of any logs whose callback function is
* <b>cb</b>. */
void
change_callback_log_severity(int loglevelMin, int loglevelMax,
log_callback cb)
{
logfile_t *lf;
log_severity_list_t severities;
set_log_severity_config(loglevelMin, loglevelMax, &severities);
LOCK_LOGS();
for (lf = logfiles; lf; lf = lf->next) {
if (lf->callback == cb) {
memcpy(lf->severities, &severities, sizeof(severities));
}
}
log_global_min_severity_ = get_min_log_level();
UNLOCK_LOGS();
}
/** If there are any log messages that were generated with LD_NOCB waiting to
* be sent to callback-based loggers, send them now. */
void
flush_pending_log_callbacks(void)
{
logfile_t *lf;
smartlist_t *messages, *messages_tmp;
LOCK_LOGS();
if (!pending_cb_messages || 0 == smartlist_len(pending_cb_messages)) {
UNLOCK_LOGS();
return;
}
messages = pending_cb_messages;
pending_cb_messages = smartlist_new();
do {
SMARTLIST_FOREACH_BEGIN(messages, pending_log_message_t *, msg) {
const int severity = msg->severity;
const int domain = msg->domain;
for (lf = logfiles; lf; lf = lf->next) {
if (! lf->callback || lf->seems_dead ||
! (lf->severities->masks[SEVERITY_MASK_IDX(severity)] & domain)) {
continue;
}
lf->callback(severity, domain, msg->msg);
}
pending_log_message_free(msg);
} SMARTLIST_FOREACH_END(msg);
smartlist_clear(messages);
messages_tmp = pending_cb_messages;
pending_cb_messages = messages;
messages = messages_tmp;
} while (smartlist_len(messages));
smartlist_free(messages);
UNLOCK_LOGS();
}
/** Flush all the messages we stored from startup while waiting for log
* initialization.
*/
void
flush_log_messages_from_startup(void)
{
logfile_t *lf;
LOCK_LOGS();
queue_startup_messages = 0;
pending_startup_messages_len = 0;
if (! pending_startup_messages)
goto out;
SMARTLIST_FOREACH_BEGIN(pending_startup_messages, pending_log_message_t *,
msg) {
int callbacks_deferred = 0;
for (lf = logfiles; lf; lf = lf->next) {
if (! logfile_wants_message(lf, msg->severity, msg->domain))
continue;
/* We configure a temporary startup log that goes to stdout, so we
* shouldn't replay to stdout/stderr*/
if (lf->fd == STDOUT_FILENO || lf->fd == STDERR_FILENO) {
continue;
}
logfile_deliver(lf, msg->fullmsg, strlen(msg->fullmsg), msg->msg,
msg->domain, msg->severity, &callbacks_deferred);
}
pending_log_message_free(msg);
} SMARTLIST_FOREACH_END(msg);
smartlist_free(pending_startup_messages);
pending_startup_messages = NULL;
out:
UNLOCK_LOGS();
}
/** Close any log handlers added by add_temp_log() or marked by
* mark_logs_temp(). */
void
close_temp_logs(void)
{
logfile_t *lf, **p;
LOCK_LOGS();
for (p = &logfiles; *p; ) {
if ((*p)->is_temporary) {
lf = *p;
/* we use *p here to handle the edge case of the head of the list */
*p = (*p)->next;
close_log(lf);
log_free(lf);
} else {
p = &((*p)->next);
}
}
log_global_min_severity_ = get_min_log_level();
UNLOCK_LOGS();
}
/** Make all currently temporary logs (set to be closed by close_temp_logs)
* live again, and close all non-temporary logs. */
void
rollback_log_changes(void)
{
logfile_t *lf;
LOCK_LOGS();
for (lf = logfiles; lf; lf = lf->next)
lf->is_temporary = ! lf->is_temporary;
UNLOCK_LOGS();
close_temp_logs();
}
/** Configure all log handles to be closed by close_temp_logs(). */
void
mark_logs_temp(void)
{
logfile_t *lf;
LOCK_LOGS();
for (lf = logfiles; lf; lf = lf->next)
lf->is_temporary = 1;
UNLOCK_LOGS();
}
/**
* Add a log handler to send messages to <b>filename</b>. If opening the
* logfile fails, -1 is returned and errno is set appropriately (by open(2)).
*/
int
add_file_log(const log_severity_list_t *severity, const char *filename,
const int truncate_log)
{
int fd;
logfile_t *lf;
int open_flags = O_WRONLY|O_CREAT;
open_flags |= truncate_log ? O_TRUNC : O_APPEND;
fd = tor_open_cloexec(filename, open_flags, 0640);
if (fd<0)
return -1;
if (tor_fd_seekend(fd)<0) {
close(fd);
return -1;
}
LOCK_LOGS();
add_stream_log_impl(severity, filename, fd);
logfiles->needs_close = 1;
lf = logfiles;
log_global_min_severity_ = get_min_log_level();
if (log_tor_version(lf, 0) < 0) {
delete_log(lf);
}
UNLOCK_LOGS();
return 0;
}
#ifdef HAVE_SYSLOG_H
/**
* Add a log handler to send messages to they system log facility.
*
* If this is the first log handler, opens syslog with ident Tor or
* Tor-<syslog_identity_tag> if that is not NULL.
*/
int
add_syslog_log(const log_severity_list_t *severity,
const char* syslog_identity_tag)
{
logfile_t *lf;
if (syslog_count++ == 0) {
/* This is the first syslog. */
static char buf[256];
if (syslog_identity_tag) {
tor_snprintf(buf, sizeof(buf), "Tor-%s", syslog_identity_tag);
} else {
tor_snprintf(buf, sizeof(buf), "Tor");
}
openlog(buf, LOG_PID | LOG_NDELAY, LOGFACILITY);
}
lf = tor_malloc_zero(sizeof(logfile_t));
lf->fd = -1;
lf->severities = tor_memdup(severity, sizeof(log_severity_list_t));
lf->filename = tor_strdup("<syslog>");
lf->is_syslog = 1;
LOCK_LOGS();
lf->next = logfiles;
logfiles = lf;
log_global_min_severity_ = get_min_log_level();
UNLOCK_LOGS();
return 0;
}
#endif /* defined(HAVE_SYSLOG_H) */
#ifdef HAVE_ANDROID_LOG_H
/**
* Add a log handler to send messages to the Android platform log facility.
*/
int
add_android_log(const log_severity_list_t *severity,
const char *android_tag)
{
logfile_t *lf = NULL;
lf = tor_malloc_zero(sizeof(logfile_t));
lf->fd = -1;
lf->severities = tor_memdup(severity, sizeof(log_severity_list_t));
lf->filename = tor_strdup("<android>");
lf->is_android = 1;
if (android_tag == NULL)
lf->android_tag = tor_strdup("Tor");
else {
char buf[256];
tor_snprintf(buf, sizeof(buf), "Tor-%s", android_tag);
lf->android_tag = tor_strdup(buf);
}
LOCK_LOGS();
lf->next = logfiles;
logfiles = lf;
log_global_min_severity_ = get_min_log_level();
UNLOCK_LOGS();
return 0;
}
#endif // HAVE_ANDROID_LOG_H.
/** If <b>level</b> is a valid log severity, return the corresponding
* numeric value. Otherwise, return -1. */
int
parse_log_level(const char *level)
{
if (!strcasecmp(level, "err"))
return LOG_ERR;
if (!strcasecmp(level, "warn"))
return LOG_WARN;
if (!strcasecmp(level, "notice"))
return LOG_NOTICE;
if (!strcasecmp(level, "info"))
return LOG_INFO;
if (!strcasecmp(level, "debug"))
return LOG_DEBUG;
return -1;
}
/** Return the string equivalent of a given log level. */
const char *
log_level_to_string(int level)
{
return sev_to_string(level);
}
/** NULL-terminated array of names for log domains such that domain_list[dom]
* is a description of <b>dom</b>.
*
* Remember to update doc/tor.1.txt if you modify this list.
* */
static const char *domain_list[] = {
"GENERAL", "CRYPTO", "NET", "CONFIG", "FS", "PROTOCOL", "MM",
"HTTP", "APP", "CONTROL", "CIRC", "REND", "BUG", "DIR", "DIRSERV",
"OR", "EDGE", "ACCT", "HIST", "HANDSHAKE", "HEARTBEAT", "CHANNEL",
"SCHED", "GUARD", "CONSDIFF", "DOS", NULL
};
/** Return a bitmask for the log domain for which <b>domain</b> is the name,
* or 0 if there is no such name. */
static log_domain_mask_t
parse_log_domain(const char *domain)
{
int i;
for (i=0; domain_list[i]; ++i) {
if (!strcasecmp(domain, domain_list[i]))
return (1u<<i);
}
return 0;
}
/** Translate a bitmask of log domains to a string. */
static char *
domain_to_string(log_domain_mask_t domain, char *buf, size_t buflen)
{
char *cp = buf;
char *eos = buf+buflen;
buf[0] = '\0';
if (! domain)
return buf;
while (1) {
const char *d;
int bit = tor_log2(domain);
size_t n;
if ((unsigned)bit >= ARRAY_LENGTH(domain_list)-1 ||
bit >= N_LOGGING_DOMAINS) {
tor_snprintf(buf, buflen, "<BUG:Unknown domain %lx>", (long)domain);
return buf+strlen(buf);
}
d = domain_list[bit];
n = strlcpy(cp, d, eos-cp);
if (n >= buflen) {
tor_snprintf(buf, buflen, "<BUG:Truncating domain %lx>", (long)domain);
return buf+strlen(buf);
}
cp += n;
domain &= ~(1<<bit);
if (domain == 0 || (eos-cp) < 2)
return cp;
memcpy(cp, ",", 2); /*Nul-terminated ,"*/
cp++;
}
}
/** Parse a log severity pattern in *<b>cfg_ptr</b>. Advance cfg_ptr after
* the end of the severityPattern. Set the value of <b>severity_out</b> to
* the parsed pattern. Return 0 on success, -1 on failure.
*
* The syntax for a SeverityPattern is:
* <pre>
* SeverityPattern = *(DomainSeverity SP)* DomainSeverity
* DomainSeverity = (DomainList SP)? SeverityRange
* SeverityRange = MinSeverity ("-" MaxSeverity )?
* DomainList = "[" (SP? DomainSpec SP? ",") SP? DomainSpec "]"
* DomainSpec = "*" | Domain | "~" Domain
* </pre>
* A missing MaxSeverity defaults to ERR. Severities and domains are
* case-insensitive. "~" indicates negation for a domain; negation happens
* last inside a DomainList. Only one SeverityRange without a DomainList is
* allowed per line.
*/
int
parse_log_severity_config(const char **cfg_ptr,
log_severity_list_t *severity_out)
{
const char *cfg = *cfg_ptr;
int got_anything = 0;
int got_an_unqualified_range = 0;
memset(severity_out, 0, sizeof(*severity_out));
cfg = eat_whitespace(cfg);
while (*cfg) {
const char *dash, *space;
char *sev_lo, *sev_hi;
int low, high, i;
log_domain_mask_t domains = ~0u;
if (*cfg == '[') {
int err = 0;
char *domains_str;
smartlist_t *domains_list;
log_domain_mask_t neg_domains = 0;
const char *closebracket = strchr(cfg, ']');
if (!closebracket)
return -1;
domains = 0;
domains_str = tor_strndup(cfg+1, closebracket-cfg-1);
domains_list = smartlist_new();
smartlist_split_string(domains_list, domains_str, ",", SPLIT_SKIP_SPACE,
-1);
tor_free(domains_str);
SMARTLIST_FOREACH_BEGIN(domains_list, const char *, domain) {
if (!strcmp(domain, "*")) {
domains = ~0u;
} else {
int d;
int negate=0;
if (*domain == '~') {
negate = 1;
++domain;
}
d = parse_log_domain(domain);
if (!d) {
log_warn(LD_CONFIG, "No such logging domain as %s", domain);
err = 1;
} else {
if (negate)
neg_domains |= d;
else
domains |= d;
}
}
} SMARTLIST_FOREACH_END(domain);
SMARTLIST_FOREACH(domains_list, char *, d, tor_free(d));
smartlist_free(domains_list);
if (err)
return -1;
if (domains == 0 && neg_domains)
domains = ~neg_domains;
else
domains &= ~neg_domains;
cfg = eat_whitespace(closebracket+1);
} else {
++got_an_unqualified_range;
}
if (!strcasecmpstart(cfg, "file") ||
!strcasecmpstart(cfg, "stderr") ||
!strcasecmpstart(cfg, "stdout") ||
!strcasecmpstart(cfg, "syslog") ||
!strcasecmpstart(cfg, "android")) {
goto done;
}
if (got_an_unqualified_range > 1)
return -1;
space = find_whitespace(cfg);
dash = strchr(cfg, '-');
if (dash && dash < space) {
sev_lo = tor_strndup(cfg, dash-cfg);
sev_hi = tor_strndup(dash+1, space-(dash+1));
} else {
sev_lo = tor_strndup(cfg, space-cfg);
sev_hi = tor_strdup("ERR");
}
low = parse_log_level(sev_lo);
high = parse_log_level(sev_hi);
tor_free(sev_lo);
tor_free(sev_hi);
if (low == -1)
return -1;
if (high == -1)
return -1;
got_anything = 1;
for (i=low; i >= high; --i)
severity_out->masks[SEVERITY_MASK_IDX(i)] |= domains;
cfg = eat_whitespace(space);
}
done:
*cfg_ptr = cfg;
return got_anything ? 0 : -1;
}
/** Return the least severe log level that any current log is interested in. */
int
get_min_log_level(void)
{
logfile_t *lf;
int i;
int min = LOG_ERR;
for (lf = logfiles; lf; lf = lf->next) {
for (i = LOG_DEBUG; i > min; --i)
if (lf->severities->masks[SEVERITY_MASK_IDX(i)])
min = i;
}
return min;
}
/** Switch all logs to output at most verbose level. */
void
switch_logs_debug(void)
{
logfile_t *lf;
int i;
LOCK_LOGS();
for (lf = logfiles; lf; lf=lf->next) {
for (i = LOG_DEBUG; i >= LOG_ERR; --i)
lf->severities->masks[SEVERITY_MASK_IDX(i)] = ~0u;
}
log_global_min_severity_ = get_min_log_level();
UNLOCK_LOGS();
}
/** Truncate all the log files. */
void
truncate_logs(void)
{
logfile_t *lf;
for (lf = logfiles; lf; lf = lf->next) {
if (lf->fd >= 0) {
tor_ftruncate(lf->fd);
}
}
}