xref: /third_party/openssl/crypto/trace.c (revision e1051a39) 
1/*
2 * Copyright 2019-2023 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License").  You may not use
5 * this file except in compliance with the License.  You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include <stdio.h>
11#include <string.h>
12
13#include "internal/thread_once.h"
14#include <openssl/bio.h>
15#include <openssl/crypto.h>
16#include <openssl/trace.h>
17#include "internal/bio.h"
18#include "internal/nelem.h"
19#include "internal/refcount.h"
20#include "crypto/cryptlib.h"
21
22#ifndef OPENSSL_NO_TRACE
23
24static CRYPTO_RWLOCK *trace_lock = NULL;
25
26static const BIO  *current_channel = NULL;
27
28/*-
29 * INTERNAL TRACE CHANNEL IMPLEMENTATION
30 *
31 * For our own flexibility, all trace categories are associated with a
32 * BIO sink object, also called the trace channel. Instead of a BIO object,
33 * the application can also provide a callback function, in which case an
34 * internal trace channel is attached, which simply calls the registered
35 * callback function.
36 */
37static int trace_write(BIO *b, const char *buf,
38                               size_t num, size_t *written);
39static int trace_puts(BIO *b, const char *str);
40static long trace_ctrl(BIO *channel, int cmd, long argl, void *argp);
41static int trace_free(BIO *b);
42
43static const BIO_METHOD trace_method = {
44    BIO_TYPE_SOURCE_SINK,
45    "trace",
46    trace_write,
47    NULL,                        /* old write */
48    NULL,                        /* read_ex */
49    NULL,                        /* read */
50    trace_puts,
51    NULL,                        /* gets */
52    trace_ctrl,                  /* ctrl */
53    NULL,                        /* create */
54    trace_free,                  /* free */
55    NULL,                        /* callback_ctrl */
56};
57
58struct trace_data_st {
59    OSSL_trace_cb callback;
60    int category;
61    void *data;
62};
63
64static int trace_write(BIO *channel,
65                       const char *buf, size_t num, size_t *written)
66{
67    struct trace_data_st *ctx = BIO_get_data(channel);
68    size_t cnt = ctx->callback(buf, num, ctx->category, OSSL_TRACE_CTRL_WRITE,
69                               ctx->data);
70
71    *written = cnt;
72    return cnt != 0;
73}
74
75static int trace_puts(BIO *channel, const char *str)
76{
77    size_t written;
78
79    if (trace_write(channel, str, strlen(str), &written))
80        return (int)written;
81
82    return EOF;
83}
84
85static long trace_ctrl(BIO *channel, int cmd, long argl, void *argp)
86{
87    struct trace_data_st *ctx = BIO_get_data(channel);
88
89    switch (cmd) {
90    case OSSL_TRACE_CTRL_BEGIN:
91    case OSSL_TRACE_CTRL_END:
92        /* We know that the callback is likely to return 0 here */
93        ctx->callback("", 0, ctx->category, cmd, ctx->data);
94        return 1;
95    default:
96        break;
97    }
98    return -2;                   /* Unsupported */
99}
100
101static int trace_free(BIO *channel)
102{
103    if (channel == NULL)
104        return 0;
105    OPENSSL_free(BIO_get_data(channel));
106    return 1;
107}
108#endif
109
110/*-
111 * TRACE
112 */
113
114/* Helper struct and macro to get name string to number mapping */
115struct trace_category_st {
116    const char * const name;
117    const int num;
118};
119#define TRACE_CATEGORY_(name)       { #name, OSSL_TRACE_CATEGORY_##name }
120
121static const struct trace_category_st
122    trace_categories[OSSL_TRACE_CATEGORY_NUM] = {
123    TRACE_CATEGORY_(ALL),
124    TRACE_CATEGORY_(TRACE),
125    TRACE_CATEGORY_(INIT),
126    TRACE_CATEGORY_(TLS),
127    TRACE_CATEGORY_(TLS_CIPHER),
128    TRACE_CATEGORY_(CONF),
129    TRACE_CATEGORY_(ENGINE_TABLE),
130    TRACE_CATEGORY_(ENGINE_REF_COUNT),
131    TRACE_CATEGORY_(PKCS5V2),
132    TRACE_CATEGORY_(PKCS12_KEYGEN),
133    TRACE_CATEGORY_(PKCS12_DECRYPT),
134    TRACE_CATEGORY_(X509V3_POLICY),
135    TRACE_CATEGORY_(BN_CTX),
136    TRACE_CATEGORY_(CMP),
137    TRACE_CATEGORY_(STORE),
138    TRACE_CATEGORY_(DECODER),
139    TRACE_CATEGORY_(ENCODER),
140    TRACE_CATEGORY_(REF_COUNT)
141};
142
143const char *OSSL_trace_get_category_name(int num)
144{
145    if (num < 0 || (size_t)num >= OSSL_NELEM(trace_categories))
146        return NULL;
147    /*
148     * Partial check that OSSL_TRACE_CATEGORY_... macros
149     * are synced with trace_categories array
150     */
151    if (!ossl_assert(trace_categories[num].name != NULL)
152        || !ossl_assert(trace_categories[num].num == num))
153        return NULL;
154    return trace_categories[num].name;
155}
156
157int OSSL_trace_get_category_num(const char *name)
158{
159    size_t i;
160
161    if (name == NULL)
162        return -1;
163
164    for (i = 0; i < OSSL_NELEM(trace_categories); i++)
165        if (OPENSSL_strcasecmp(name, trace_categories[i].name) == 0)
166            return trace_categories[i].num;
167
168    return -1; /* not found */
169}
170
171#ifndef OPENSSL_NO_TRACE
172
173/* We use one trace channel for each trace category */
174static struct {
175    enum { SIMPLE_CHANNEL, CALLBACK_CHANNEL } type;
176    BIO *bio;
177    char *prefix;
178    char *suffix;
179} trace_channels[OSSL_TRACE_CATEGORY_NUM] = {
180    { 0, NULL, NULL, NULL },
181};
182
183#endif
184
185#ifndef OPENSSL_NO_TRACE
186
187enum {
188    CHANNEL,
189    PREFIX,
190    SUFFIX
191};
192
193static int trace_attach_cb(int category, int type, const void *data)
194{
195    switch (type) {
196    case CHANNEL:
197        OSSL_TRACE2(TRACE, "Attach channel %p to category '%s'\n",
198                    data, trace_categories[category].name);
199        break;
200    case PREFIX:
201        OSSL_TRACE2(TRACE, "Attach prefix \"%s\" to category '%s'\n",
202                    (const char *)data, trace_categories[category].name);
203        break;
204    case SUFFIX:
205        OSSL_TRACE2(TRACE, "Attach suffix \"%s\" to category '%s'\n",
206                    (const char *)data, trace_categories[category].name);
207        break;
208    default:                     /* No clue */
209        break;
210    }
211    return 1;
212}
213
214static int trace_detach_cb(int category, int type, const void *data)
215{
216    switch (type) {
217    case CHANNEL:
218        OSSL_TRACE2(TRACE, "Detach channel %p from category '%s'\n",
219                    data, trace_categories[category].name);
220        break;
221    case PREFIX:
222        OSSL_TRACE2(TRACE, "Detach prefix \"%s\" from category '%s'\n",
223                    (const char *)data, trace_categories[category].name);
224        break;
225    case SUFFIX:
226        OSSL_TRACE2(TRACE, "Detach suffix \"%s\" from category '%s'\n",
227                    (const char *)data, trace_categories[category].name);
228        break;
229    default:                     /* No clue */
230        break;
231    }
232    return 1;
233}
234
235static int do_ossl_trace_init(void);
236static CRYPTO_ONCE trace_inited = CRYPTO_ONCE_STATIC_INIT;
237DEFINE_RUN_ONCE_STATIC(ossl_trace_init)
238{
239    return do_ossl_trace_init();
240}
241
242static int set_trace_data(int category, int type, BIO **channel,
243                          const char **prefix, const char **suffix,
244                          int (*attach_cb)(int, int, const void *),
245                          int (*detach_cb)(int, int, const void *))
246{
247    BIO *curr_channel = NULL;
248    char *curr_prefix = NULL;
249    char *curr_suffix = NULL;
250
251    /* Ensure do_ossl_trace_init() is called once */
252    if (!RUN_ONCE(&trace_inited, ossl_trace_init))
253        return 0;
254
255    curr_channel = trace_channels[category].bio;
256    curr_prefix = trace_channels[category].prefix;
257    curr_suffix = trace_channels[category].suffix;
258
259    /* Make sure to run the detach callback first on all data */
260    if (prefix != NULL && curr_prefix != NULL) {
261        detach_cb(category, PREFIX, curr_prefix);
262    }
263
264    if (suffix != NULL && curr_suffix != NULL) {
265        detach_cb(category, SUFFIX, curr_suffix);
266    }
267
268    if (channel != NULL && curr_channel != NULL) {
269        detach_cb(category, CHANNEL, curr_channel);
270    }
271
272    /* After detach callbacks are done, clear data where appropriate */
273    if (prefix != NULL && curr_prefix != NULL) {
274        OPENSSL_free(curr_prefix);
275        trace_channels[category].prefix = NULL;
276    }
277
278    if (suffix != NULL && curr_suffix != NULL) {
279        OPENSSL_free(curr_suffix);
280        trace_channels[category].suffix = NULL;
281    }
282
283    if (channel != NULL && curr_channel != NULL) {
284        BIO_free(curr_channel);
285        trace_channels[category].type = 0;
286        trace_channels[category].bio = NULL;
287    }
288
289    /* Before running callbacks are done, set new data where appropriate */
290    if (prefix != NULL && *prefix != NULL) {
291        if ((curr_prefix = OPENSSL_strdup(*prefix)) == NULL)
292            return 0;
293        trace_channels[category].prefix = curr_prefix;
294    }
295
296    if (suffix != NULL && *suffix != NULL) {
297        if ((curr_suffix = OPENSSL_strdup(*suffix)) == NULL)
298            return 0;
299        trace_channels[category].suffix = curr_suffix;
300    }
301
302    if (channel != NULL && *channel != NULL) {
303        trace_channels[category].type = type;
304        trace_channels[category].bio = *channel;
305        /*
306         * This must not be done before setting prefix/suffix,
307         * as those may fail, and then the caller is mislead to free *channel.
308         */
309    }
310
311    /* Finally, run the attach callback on the new data */
312    if (channel != NULL && *channel != NULL) {
313        attach_cb(category, CHANNEL, *channel);
314    }
315
316    if (prefix != NULL && *prefix != NULL) {
317        attach_cb(category, PREFIX, *prefix);
318    }
319
320    if (suffix != NULL && *suffix != NULL) {
321        attach_cb(category, SUFFIX, *suffix);
322    }
323
324    return 1;
325}
326
327static int do_ossl_trace_init(void)
328{
329    trace_lock = CRYPTO_THREAD_lock_new();
330    return trace_lock != NULL;
331}
332
333#endif
334
335void ossl_trace_cleanup(void)
336{
337#ifndef OPENSSL_NO_TRACE
338    int category;
339    BIO *channel = NULL;
340    const char *prefix = NULL;
341    const char *suffix = NULL;
342
343    for (category = 0; category < OSSL_TRACE_CATEGORY_NUM; category++) {
344        /* We force the TRACE category to be treated last */
345        if (category == OSSL_TRACE_CATEGORY_TRACE)
346            continue;
347        set_trace_data(category, 0, &channel, &prefix, &suffix,
348                       trace_attach_cb, trace_detach_cb);
349    }
350    set_trace_data(OSSL_TRACE_CATEGORY_TRACE, 0, &channel,
351                   &prefix, &suffix,
352                   trace_attach_cb, trace_detach_cb);
353    CRYPTO_THREAD_lock_free(trace_lock);
354#endif
355}
356
357int OSSL_trace_set_channel(int category, BIO *channel)
358{
359#ifndef OPENSSL_NO_TRACE
360    if (category >= 0 && category < OSSL_TRACE_CATEGORY_NUM)
361        return set_trace_data(category, SIMPLE_CHANNEL, &channel, NULL, NULL,
362                              trace_attach_cb, trace_detach_cb);
363#endif
364    return 0;
365}
366
367#ifndef OPENSSL_NO_TRACE
368static int trace_attach_w_callback_cb(int category, int type, const void *data)
369{
370    switch (type) {
371    case CHANNEL:
372        OSSL_TRACE2(TRACE,
373                    "Attach channel %p to category '%s' (with callback)\n",
374                    data, trace_categories[category].name);
375        break;
376    case PREFIX:
377        OSSL_TRACE2(TRACE, "Attach prefix \"%s\" to category '%s'\n",
378                    (const char *)data, trace_categories[category].name);
379        break;
380    case SUFFIX:
381        OSSL_TRACE2(TRACE, "Attach suffix \"%s\" to category '%s'\n",
382                    (const char *)data, trace_categories[category].name);
383        break;
384    default:                     /* No clue */
385        break;
386    }
387    return 1;
388}
389#endif
390
391int OSSL_trace_set_callback(int category, OSSL_trace_cb callback, void *data)
392{
393#ifndef OPENSSL_NO_TRACE
394    BIO *channel = NULL;
395    struct trace_data_st *trace_data = NULL;
396
397    if (category < 0 || category >= OSSL_TRACE_CATEGORY_NUM)
398        return 0;
399
400    if (callback != NULL) {
401        if ((channel = BIO_new(&trace_method)) == NULL
402            || (trace_data =
403                OPENSSL_zalloc(sizeof(struct trace_data_st))) == NULL)
404            goto err;
405
406        trace_data->callback = callback;
407        trace_data->category = category;
408        trace_data->data = data;
409
410        BIO_set_data(channel, trace_data);
411    }
412
413    if (!set_trace_data(category, CALLBACK_CHANNEL, &channel, NULL, NULL,
414                        trace_attach_w_callback_cb, trace_detach_cb))
415        goto err;
416
417    return 1;
418
419 err:
420    BIO_free(channel);
421    OPENSSL_free(trace_data);
422#endif
423
424    return 0;
425}
426
427int OSSL_trace_set_prefix(int category, const char *prefix)
428{
429#ifndef OPENSSL_NO_TRACE
430    if (category >= 0 && category < OSSL_TRACE_CATEGORY_NUM)
431        return set_trace_data(category, 0, NULL, &prefix, NULL,
432                              trace_attach_cb, trace_detach_cb);
433#endif
434    return 0;
435}
436
437int OSSL_trace_set_suffix(int category, const char *suffix)
438{
439#ifndef OPENSSL_NO_TRACE
440    if (category >= 0 && category < OSSL_TRACE_CATEGORY_NUM)
441        return set_trace_data(category, 0, NULL, NULL, &suffix,
442                              trace_attach_cb, trace_detach_cb);
443#endif
444    return 0;
445}
446
447#ifndef OPENSSL_NO_TRACE
448static int ossl_trace_get_category(int category)
449{
450    if (category < 0 || category >= OSSL_TRACE_CATEGORY_NUM)
451        return -1;
452    if (trace_channels[category].bio != NULL)
453        return category;
454    return OSSL_TRACE_CATEGORY_ALL;
455}
456#endif
457
458int OSSL_trace_enabled(int category)
459{
460    int ret = 0;
461#ifndef OPENSSL_NO_TRACE
462    category = ossl_trace_get_category(category);
463    if (category >= 0)
464        ret = trace_channels[category].bio != NULL;
465#endif
466    return ret;
467}
468
469BIO *OSSL_trace_begin(int category)
470{
471    BIO *channel = NULL;
472#ifndef OPENSSL_NO_TRACE
473    char *prefix = NULL;
474
475    category = ossl_trace_get_category(category);
476    if (category < 0)
477        return NULL;
478
479    channel = trace_channels[category].bio;
480    prefix = trace_channels[category].prefix;
481
482    if (channel != NULL) {
483        if (!CRYPTO_THREAD_write_lock(trace_lock))
484            return NULL;
485        current_channel = channel;
486        switch (trace_channels[category].type) {
487        case SIMPLE_CHANNEL:
488            if (prefix != NULL) {
489                (void)BIO_puts(channel, prefix);
490                (void)BIO_puts(channel, "\n");
491            }
492            break;
493        case CALLBACK_CHANNEL:
494            (void)BIO_ctrl(channel, OSSL_TRACE_CTRL_BEGIN,
495                           prefix == NULL ? 0 : strlen(prefix), prefix);
496            break;
497        }
498    }
499#endif
500    return channel;
501}
502
503void OSSL_trace_end(int category, BIO * channel)
504{
505#ifndef OPENSSL_NO_TRACE
506    char *suffix = NULL;
507
508    category = ossl_trace_get_category(category);
509    if (category < 0)
510        return;
511    suffix = trace_channels[category].suffix;
512    if (channel != NULL
513        && ossl_assert(channel == current_channel)) {
514        (void)BIO_flush(channel);
515        switch (trace_channels[category].type) {
516        case SIMPLE_CHANNEL:
517            if (suffix != NULL) {
518                (void)BIO_puts(channel, suffix);
519                (void)BIO_puts(channel, "\n");
520            }
521            break;
522        case CALLBACK_CHANNEL:
523            (void)BIO_ctrl(channel, OSSL_TRACE_CTRL_END,
524                           suffix == NULL ? 0 : strlen(suffix), suffix);
525            break;
526        }
527        current_channel = NULL;
528        CRYPTO_THREAD_unlock(trace_lock);
529    }
530#endif
531}
532