`ssh-log-pw-blank': known password fields are now omitted from SSH packet logs
[u/mdw/putty] / logging.c
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <ctype.h>
4
5 #include <time.h>
6 #include <assert.h>
7
8 #include "putty.h"
9
10 /* log session to file stuff ... */
11 struct LogContext {
12 FILE *lgfp;
13 Filename currlogfilename;
14 void *frontend;
15 Config cfg;
16 };
17
18 static void xlatlognam(Filename *d, Filename s, char *hostname, struct tm *tm);
19
20 /*
21 * Log session traffic.
22 */
23 void logtraffic(void *handle, unsigned char c, int logmode)
24 {
25 struct LogContext *ctx = (struct LogContext *)handle;
26 if (ctx->cfg.logtype > 0) {
27 if (ctx->cfg.logtype == logmode) {
28 /* deferred open file from pgm start? */
29 if (!ctx->lgfp)
30 logfopen(ctx);
31 if (ctx->lgfp)
32 fputc(c, ctx->lgfp);
33 }
34 }
35 }
36
37 /*
38 * Flush any open log file.
39 */
40 void logflush(void *handle) {
41 struct LogContext *ctx = (struct LogContext *)handle;
42 if (ctx->cfg.logtype > 0)
43 if (ctx->lgfp)
44 fflush(ctx->lgfp);
45 }
46
47 /*
48 * Log an Event Log entry. Used in SSH packet logging mode; this is
49 * also as convenient a place as any to put the output of Event Log
50 * entries to stderr when a command-line tool is in verbose mode.
51 * (In particular, this is a better place to put it than in the
52 * front ends, because it only has to be done once for all
53 * platforms. Platforms which don't have a meaningful stderr can
54 * just avoid defining FLAG_STDERR.
55 */
56 void log_eventlog(void *handle, const char *event)
57 {
58 struct LogContext *ctx = (struct LogContext *)handle;
59 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) {
60 fprintf(stderr, "%s\n", event);
61 fflush(stderr);
62 }
63 if (ctx->cfg.logtype != LGTYP_PACKETS)
64 return;
65 if (!ctx->lgfp)
66 logfopen(ctx);
67 if (ctx->lgfp)
68 fprintf(ctx->lgfp, "Event Log: %s\r\n", event);
69 }
70
71 /*
72 * Log an SSH packet.
73 * If n_blanks != 0, blank or omit some parts.
74 * Set of blanking areas must be in increasing order.
75 */
76 void log_packet(void *handle, int direction, int type,
77 char *texttype, void *data, int len,
78 int n_blanks, const struct logblank_t *blanks)
79 {
80 struct LogContext *ctx = (struct LogContext *)handle;
81 char dumpdata[80], smalldata[5];
82
83 if (ctx->cfg.logtype != LGTYP_PACKETS)
84 return;
85 if (!ctx->lgfp)
86 logfopen(ctx);
87 if (ctx->lgfp) {
88 int p = 0, b = 0, omitted = 0;
89 int output_pos = 0; /* NZ if pending output in dumpdata */
90
91 /* Packet header. */
92 fprintf(ctx->lgfp, "%s packet type %d / 0x%02x (%s)\r\n",
93 direction == PKT_INCOMING ? "Incoming" : "Outgoing",
94 type, type, texttype);
95
96 /*
97 * Output a hex/ASCII dump of the packet body, blanking/omitting
98 * parts as specified.
99 */
100 while (p < len) {
101 int blktype;
102
103 /* Move to a current entry in the blanking array. */
104 while ((b < n_blanks) &&
105 (p >= blanks[b].offset + blanks[b].len))
106 b++;
107 /* Work out what type of blanking to apply to
108 * this byte. */
109 blktype = PKTLOG_EMIT; /* default */
110 if ((b < n_blanks) &&
111 (p >= blanks[b].offset) &&
112 (p < blanks[b].offset + blanks[b].len))
113 blktype = blanks[b].type;
114
115 /* If we're about to stop omitting, it's time to say how
116 * much we omitted. */
117 if ((blktype != PKTLOG_OMIT) && omitted) {
118 fprintf(ctx->lgfp, " (%d byte%s omitted)\r\n",
119 omitted, (omitted==1?"":"s"));
120 omitted = 0;
121 }
122
123 /* (Re-)initialise dumpdata as necessary
124 * (start of row, or if we've just stopped omitting) */
125 if (!output_pos && !omitted)
126 sprintf(dumpdata, " %08x%*s\r\n", p-(p%16), 1+3*16+2+16, "");
127
128 /* Deal with the current byte. */
129 if (blktype == PKTLOG_OMIT) {
130 omitted++;
131 } else {
132 int c;
133 if (blktype == PKTLOG_BLANK) {
134 c = 'X';
135 sprintf(smalldata, "XX");
136 } else { /* PKTLOG_EMIT */
137 c = ((unsigned char *)data)[p];
138 sprintf(smalldata, "%02x", c);
139 }
140 dumpdata[10+2+3*(p%16)] = smalldata[0];
141 dumpdata[10+2+3*(p%16)+1] = smalldata[1];
142 dumpdata[10+1+3*16+2+(p%16)] = (isprint(c) ? c : '.');
143 output_pos = (p%16) + 1;
144 }
145
146 p++;
147
148 /* Flush row if necessary */
149 if (((p % 16) == 0) || (p == len) || omitted) {
150 if (output_pos) {
151 strcpy(dumpdata + 10+1+3*16+2+output_pos, "\r\n");
152 fputs(dumpdata, ctx->lgfp);
153 output_pos = 0;
154 }
155 }
156
157 }
158
159 /* Tidy up */
160 if (omitted)
161 fprintf(ctx->lgfp, " (%d byte%s omitted)\r\n",
162 omitted, (omitted==1?"":"s"));
163 fflush(ctx->lgfp);
164 }
165 }
166
167 /* open log file append/overwrite mode */
168 void logfopen(void *handle)
169 {
170 struct LogContext *ctx = (struct LogContext *)handle;
171 char buf[256];
172 time_t t;
173 struct tm tm;
174 char writemod[4];
175
176 /* Prevent repeat calls */
177 if (ctx->lgfp)
178 return;
179
180 if (!ctx->cfg.logtype)
181 return;
182 sprintf(writemod, "wb"); /* default to rewrite */
183
184 time(&t);
185 tm = *localtime(&t);
186
187 /* substitute special codes in file name */
188 xlatlognam(&ctx->currlogfilename, ctx->cfg.logfilename,ctx->cfg.host, &tm);
189
190 ctx->lgfp = f_open(ctx->currlogfilename, "r"); /* file already present? */
191 if (ctx->lgfp) {
192 int i;
193 fclose(ctx->lgfp);
194 if (ctx->cfg.logxfovr != LGXF_ASK) {
195 i = ((ctx->cfg.logxfovr == LGXF_OVR) ? 2 : 1);
196 } else
197 i = askappend(ctx->frontend, ctx->currlogfilename);
198 if (i == 1)
199 writemod[0] = 'a'; /* set append mode */
200 else if (i == 0) { /* cancelled */
201 ctx->lgfp = NULL;
202 ctx->cfg.logtype = 0; /* disable logging */
203 return;
204 }
205 }
206
207 ctx->lgfp = f_open(ctx->currlogfilename, writemod);
208 if (ctx->lgfp) { /* enter into event log */
209 /* --- write header line into log file */
210 fputs("=~=~=~=~=~=~=~=~=~=~=~= PuTTY log ", ctx->lgfp);
211 strftime(buf, 24, "%Y.%m.%d %H:%M:%S", &tm);
212 fputs(buf, ctx->lgfp);
213 fputs(" =~=~=~=~=~=~=~=~=~=~=~=\r\n", ctx->lgfp);
214
215 sprintf(buf, "%s session log (%s mode) to file: ",
216 (writemod[0] == 'a') ? "Appending" : "Writing new",
217 (ctx->cfg.logtype == LGTYP_ASCII ? "ASCII" :
218 ctx->cfg.logtype == LGTYP_DEBUG ? "raw" :
219 ctx->cfg.logtype == LGTYP_PACKETS ? "SSH packets" : "<ukwn>"));
220 /* Make sure we do not exceed the output buffer size */
221 strncat(buf, filename_to_str(&ctx->currlogfilename), 128);
222 buf[strlen(buf)] = '\0';
223 logevent(ctx->frontend, buf);
224 }
225 }
226
227 void logfclose(void *handle)
228 {
229 struct LogContext *ctx = (struct LogContext *)handle;
230 if (ctx->lgfp) {
231 fclose(ctx->lgfp);
232 ctx->lgfp = NULL;
233 }
234 }
235
236 void *log_init(void *frontend, Config *cfg)
237 {
238 struct LogContext *ctx = snew(struct LogContext);
239 ctx->lgfp = NULL;
240 ctx->frontend = frontend;
241 ctx->cfg = *cfg; /* STRUCTURE COPY */
242 return ctx;
243 }
244
245 void log_free(void *handle)
246 {
247 struct LogContext *ctx = (struct LogContext *)handle;
248
249 logfclose(ctx);
250 sfree(ctx);
251 }
252
253 void log_reconfig(void *handle, Config *cfg)
254 {
255 struct LogContext *ctx = (struct LogContext *)handle;
256 int reset_logging;
257
258 if (!filename_equal(ctx->cfg.logfilename, cfg->logfilename) ||
259 ctx->cfg.logtype != cfg->logtype)
260 reset_logging = TRUE;
261 else
262 reset_logging = FALSE;
263
264 if (reset_logging)
265 logfclose(ctx);
266
267 ctx->cfg = *cfg; /* STRUCTURE COPY */
268
269 if (reset_logging)
270 logfopen(ctx);
271 }
272
273 /*
274 * translate format codes into time/date strings
275 * and insert them into log file name
276 *
277 * "&Y":YYYY "&m":MM "&d":DD "&T":hhmm "&h":<hostname> "&&":&
278 */
279 static void xlatlognam(Filename *dest, Filename src,
280 char *hostname, struct tm *tm) {
281 char buf[10], *bufp;
282 int size;
283 char buffer[FILENAME_MAX];
284 int len = sizeof(buffer)-1;
285 char *d;
286 const char *s;
287
288 d = buffer;
289 s = filename_to_str(&src);
290
291 while (*s) {
292 /* Let (bufp, len) be the string to append. */
293 bufp = buf; /* don't usually override this */
294 if (*s == '&') {
295 char c;
296 s++;
297 size = 0;
298 if (*s) switch (c = *s++, tolower(c)) {
299 case 'y':
300 size = strftime(buf, sizeof(buf), "%Y", tm);
301 break;
302 case 'm':
303 size = strftime(buf, sizeof(buf), "%m", tm);
304 break;
305 case 'd':
306 size = strftime(buf, sizeof(buf), "%d", tm);
307 break;
308 case 't':
309 size = strftime(buf, sizeof(buf), "%H%M%S", tm);
310 break;
311 case 'h':
312 bufp = hostname;
313 size = strlen(bufp);
314 break;
315 default:
316 buf[0] = '&';
317 size = 1;
318 if (c != '&')
319 buf[size++] = c;
320 }
321 } else {
322 buf[0] = *s++;
323 size = 1;
324 }
325 if (size > len)
326 size = len;
327 memcpy(d, bufp, size);
328 d += size;
329 len -= size;
330 }
331 *d = '\0';
332
333 *dest = filename_from_str(buffer);
334 }