putty/logging.c

472 строки
12 KiB
C

/*
* Session logging.
*/
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <time.h>
#include <assert.h>
#include "putty.h"
/* log session to file stuff ... */
struct LogContext {
FILE *lgfp;
enum { L_CLOSED, L_OPENING, L_OPEN, L_ERROR } state;
bufchain queue;
Filename *currlogfilename;
void *frontend;
Conf *conf;
int logtype; /* cached out of conf */
};
static Filename *xlatlognam(Filename *s, char *hostname, struct tm *tm);
/*
* Internal wrapper function which must be called for _all_ output
* to the log file. It takes care of opening the log file if it
* isn't open, buffering data if it's in the process of being
* opened asynchronously, etc.
*/
static void logwrite(struct LogContext *ctx, void *data, int len)
{
/*
* In state L_CLOSED, we call logfopen, which will set the state
* to one of L_OPENING, L_OPEN or L_ERROR. Hence we process all of
* those three _after_ processing L_CLOSED.
*/
if (ctx->state == L_CLOSED)
logfopen(ctx);
if (ctx->state == L_OPENING) {
bufchain_add(&ctx->queue, data, len);
} else if (ctx->state == L_OPEN) {
assert(ctx->lgfp);
if (fwrite(data, 1, len, ctx->lgfp) < (size_t)len) {
logfclose(ctx);
ctx->state = L_ERROR;
/* Log state is L_ERROR so this won't cause a loop */
logevent(ctx->frontend,
"Disabled writing session log due to error while writing");
}
} /* else L_ERROR, so ignore the write */
}
/*
* Convenience wrapper on logwrite() which printf-formats the
* string.
*/
static void logprintf(struct LogContext *ctx, const char *fmt, ...)
{
va_list ap;
char *data;
va_start(ap, fmt);
data = dupvprintf(fmt, ap);
va_end(ap);
logwrite(ctx, data, strlen(data));
sfree(data);
}
/*
* Flush any open log file.
*/
void logflush(void *handle) {
struct LogContext *ctx = (struct LogContext *)handle;
if (ctx->logtype > 0)
if (ctx->state == L_OPEN)
fflush(ctx->lgfp);
}
static void logfopen_callback(void *handle, int mode)
{
struct LogContext *ctx = (struct LogContext *)handle;
char buf[256], *event;
struct tm tm;
const char *fmode;
if (mode == 0) {
ctx->state = L_ERROR; /* disable logging */
} else {
fmode = (mode == 1 ? "ab" : "wb");
ctx->lgfp = f_open(ctx->currlogfilename, fmode, FALSE);
if (ctx->lgfp)
ctx->state = L_OPEN;
else
ctx->state = L_ERROR;
}
if (ctx->state == L_OPEN) {
/* Write header line into log file. */
tm = ltime();
strftime(buf, 24, "%Y.%m.%d %H:%M:%S", &tm);
logprintf(ctx, "=~=~=~=~=~=~=~=~=~=~=~= PuTTY log %s"
" =~=~=~=~=~=~=~=~=~=~=~=\r\n", buf);
}
event = dupprintf("%s session log (%s mode) to file: %s",
ctx->state == L_ERROR ?
(mode == 0 ? "Disabled writing" : "Error writing") :
(mode == 1 ? "Appending" : "Writing new"),
(ctx->logtype == LGTYP_ASCII ? "ASCII" :
ctx->logtype == LGTYP_DEBUG ? "raw" :
ctx->logtype == LGTYP_PACKETS ? "SSH packets" :
ctx->logtype == LGTYP_SSHRAW ? "SSH raw data" :
"unknown"),
filename_to_str(ctx->currlogfilename));
logevent(ctx->frontend, event);
sfree(event);
/*
* Having either succeeded or failed in opening the log file,
* we should write any queued data out.
*/
assert(ctx->state != L_OPENING); /* make _sure_ it won't be requeued */
while (bufchain_size(&ctx->queue)) {
void *data;
int len;
bufchain_prefix(&ctx->queue, &data, &len);
logwrite(ctx, data, len);
bufchain_consume(&ctx->queue, len);
}
}
/*
* Open the log file. Takes care of detecting an already-existing
* file and asking the user whether they want to append, overwrite
* or cancel logging.
*/
void logfopen(void *handle)
{
struct LogContext *ctx = (struct LogContext *)handle;
struct tm tm;
int mode;
/* Prevent repeat calls */
if (ctx->state != L_CLOSED)
return;
if (!ctx->logtype)
return;
tm = ltime();
/* substitute special codes in file name */
if (ctx->currlogfilename)
filename_free(ctx->currlogfilename);
ctx->currlogfilename =
xlatlognam(conf_get_filename(ctx->conf, CONF_logfilename),
conf_get_str(ctx->conf, CONF_host), &tm);
ctx->lgfp = f_open(ctx->currlogfilename, "r", FALSE); /* file already present? */
if (ctx->lgfp) {
int logxfovr = conf_get_int(ctx->conf, CONF_logxfovr);
fclose(ctx->lgfp);
if (logxfovr != LGXF_ASK) {
mode = ((logxfovr == LGXF_OVR) ? 2 : 1);
} else
mode = askappend(ctx->frontend, ctx->currlogfilename,
logfopen_callback, ctx);
} else
mode = 2; /* create == overwrite */
if (mode < 0)
ctx->state = L_OPENING;
else
logfopen_callback(ctx, mode); /* open the file */
}
void logfclose(void *handle)
{
struct LogContext *ctx = (struct LogContext *)handle;
if (ctx->lgfp) {
fclose(ctx->lgfp);
ctx->lgfp = NULL;
}
ctx->state = L_CLOSED;
}
/*
* Log session traffic.
*/
void logtraffic(void *handle, unsigned char c, int logmode)
{
struct LogContext *ctx = (struct LogContext *)handle;
if (ctx->logtype > 0) {
if (ctx->logtype == logmode)
logwrite(ctx, &c, 1);
}
}
/*
* Log an Event Log entry. Used in SSH packet logging mode; this is
* also as convenient a place as any to put the output of Event Log
* entries to stderr when a command-line tool is in verbose mode.
* (In particular, this is a better place to put it than in the
* front ends, because it only has to be done once for all
* platforms. Platforms which don't have a meaningful stderr can
* just avoid defining FLAG_STDERR.
*/
void log_eventlog(void *handle, const char *event)
{
struct LogContext *ctx = (struct LogContext *)handle;
if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) {
fprintf(stderr, "%s\n", event);
fflush(stderr);
}
/* If we don't have a context yet (eg winnet.c init) then skip entirely */
if (!ctx)
return;
if (ctx->logtype != LGTYP_PACKETS &&
ctx->logtype != LGTYP_SSHRAW)
return;
logprintf(ctx, "Event Log: %s\r\n", event);
logflush(ctx);
}
/*
* Log an SSH packet.
* If n_blanks != 0, blank or omit some parts.
* Set of blanking areas must be in increasing order.
*/
void log_packet(void *handle, int direction, int type,
const char *texttype, const void *data, int len,
int n_blanks, const struct logblank_t *blanks,
const unsigned long *seq,
unsigned downstream_id, const char *additional_log_text)
{
struct LogContext *ctx = (struct LogContext *)handle;
char dumpdata[80], smalldata[5];
int p = 0, b = 0, omitted = 0;
int output_pos = 0; /* NZ if pending output in dumpdata */
if (!(ctx->logtype == LGTYP_SSHRAW ||
(ctx->logtype == LGTYP_PACKETS && texttype)))
return;
/* Packet header. */
if (texttype) {
logprintf(ctx, "%s packet ",
direction == PKT_INCOMING ? "Incoming" : "Outgoing");
if (seq)
logprintf(ctx, "#0x%lx, ", *seq);
logprintf(ctx, "type %d / 0x%02x (%s)", type, type, texttype);
if (downstream_id) {
logprintf(ctx, " on behalf of downstream #%u", downstream_id);
if (additional_log_text)
logprintf(ctx, " (%s)", additional_log_text);
}
logprintf(ctx, "\r\n");
} else {
/*
* Raw data is logged with a timestamp, so that it's possible
* to determine whether a mysterious delay occurred at the
* client or server end. (Timestamping the raw data avoids
* cluttering the normal case of only logging decrypted SSH
* messages, and also adds conceptual rigour in the case where
* an SSH message arrives in several pieces.)
*/
char buf[256];
struct tm tm;
tm = ltime();
strftime(buf, 24, "%Y-%m-%d %H:%M:%S", &tm);
logprintf(ctx, "%s raw data at %s\r\n",
direction == PKT_INCOMING ? "Incoming" : "Outgoing",
buf);
}
/*
* Output a hex/ASCII dump of the packet body, blanking/omitting
* parts as specified.
*/
while (p < len) {
int blktype;
/* Move to a current entry in the blanking array. */
while ((b < n_blanks) &&
(p >= blanks[b].offset + blanks[b].len))
b++;
/* Work out what type of blanking to apply to
* this byte. */
blktype = PKTLOG_EMIT; /* default */
if ((b < n_blanks) &&
(p >= blanks[b].offset) &&
(p < blanks[b].offset + blanks[b].len))
blktype = blanks[b].type;
/* If we're about to stop omitting, it's time to say how
* much we omitted. */
if ((blktype != PKTLOG_OMIT) && omitted) {
logprintf(ctx, " (%d byte%s omitted)\r\n",
omitted, (omitted==1?"":"s"));
omitted = 0;
}
/* (Re-)initialise dumpdata as necessary
* (start of row, or if we've just stopped omitting) */
if (!output_pos && !omitted)
sprintf(dumpdata, " %08x%*s\r\n", p-(p%16), 1+3*16+2+16, "");
/* Deal with the current byte. */
if (blktype == PKTLOG_OMIT) {
omitted++;
} else {
int c;
if (blktype == PKTLOG_BLANK) {
c = 'X';
sprintf(smalldata, "XX");
} else { /* PKTLOG_EMIT */
c = ((unsigned char *)data)[p];
sprintf(smalldata, "%02x", c);
}
dumpdata[10+2+3*(p%16)] = smalldata[0];
dumpdata[10+2+3*(p%16)+1] = smalldata[1];
dumpdata[10+1+3*16+2+(p%16)] = (isprint(c) ? c : '.');
output_pos = (p%16) + 1;
}
p++;
/* Flush row if necessary */
if (((p % 16) == 0) || (p == len) || omitted) {
if (output_pos) {
strcpy(dumpdata + 10+1+3*16+2+output_pos, "\r\n");
logwrite(ctx, dumpdata, strlen(dumpdata));
output_pos = 0;
}
}
}
/* Tidy up */
if (omitted)
logprintf(ctx, " (%d byte%s omitted)\r\n",
omitted, (omitted==1?"":"s"));
logflush(ctx);
}
void *log_init(void *frontend, Conf *conf)
{
struct LogContext *ctx = snew(struct LogContext);
ctx->lgfp = NULL;
ctx->state = L_CLOSED;
ctx->frontend = frontend;
ctx->conf = conf_copy(conf);
ctx->logtype = conf_get_int(ctx->conf, CONF_logtype);
ctx->currlogfilename = NULL;
bufchain_init(&ctx->queue);
return ctx;
}
void log_free(void *handle)
{
struct LogContext *ctx = (struct LogContext *)handle;
logfclose(ctx);
bufchain_clear(&ctx->queue);
if (ctx->currlogfilename)
filename_free(ctx->currlogfilename);
conf_free(ctx->conf);
sfree(ctx);
}
void log_reconfig(void *handle, Conf *conf)
{
struct LogContext *ctx = (struct LogContext *)handle;
int reset_logging;
if (!filename_equal(conf_get_filename(ctx->conf, CONF_logfilename),
conf_get_filename(conf, CONF_logfilename)) ||
conf_get_int(ctx->conf, CONF_logtype) !=
conf_get_int(conf, CONF_logtype))
reset_logging = TRUE;
else
reset_logging = FALSE;
if (reset_logging)
logfclose(ctx);
conf_free(ctx->conf);
ctx->conf = conf_copy(conf);
ctx->logtype = conf_get_int(ctx->conf, CONF_logtype);
if (reset_logging)
logfopen(ctx);
}
/*
* translate format codes into time/date strings
* and insert them into log file name
*
* "&Y":YYYY "&m":MM "&d":DD "&T":hhmmss "&h":<hostname> "&&":&
*/
static Filename *xlatlognam(Filename *src, char *hostname, struct tm *tm)
{
char buf[10], *bufp;
int size;
char *buffer;
int buflen, bufsize;
const char *s;
Filename *ret;
bufsize = FILENAME_MAX;
buffer = snewn(bufsize, char);
buflen = 0;
s = filename_to_str(src);
while (*s) {
/* Let (bufp, len) be the string to append. */
bufp = buf; /* don't usually override this */
if (*s == '&') {
char c;
s++;
size = 0;
if (*s) switch (c = *s++, tolower((unsigned char)c)) {
case 'y':
size = strftime(buf, sizeof(buf), "%Y", tm);
break;
case 'm':
size = strftime(buf, sizeof(buf), "%m", tm);
break;
case 'd':
size = strftime(buf, sizeof(buf), "%d", tm);
break;
case 't':
size = strftime(buf, sizeof(buf), "%H%M%S", tm);
break;
case 'h':
bufp = hostname;
size = strlen(bufp);
break;
default:
buf[0] = '&';
size = 1;
if (c != '&')
buf[size++] = c;
}
} else {
buf[0] = *s++;
size = 1;
}
if (bufsize <= buflen + size) {
bufsize = (buflen + size) * 5 / 4 + 512;
buffer = sresize(buffer, bufsize, char);
}
memcpy(buffer + buflen, bufp, size);
buflen += size;
}
buffer[buflen] = '\0';
ret = filename_from_str(buffer);
sfree(buffer);
return ret;
}