crypto/trace.c

   1 /*
   2  * Copyright 2019 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 <openssl/bio.h>
  14 #include <openssl/crypto.h>
  15 #include <openssl/trace.h>
  16 #include "internal/bio.h"
  17 #include "internal/nelem.h"
  18 #include "internal/cryptlib_int.h"
  19
  20 #include "e_os.h"                /* strcasecmp for Windows */
  21
  22 #ifndef OPENSSL_NO_TRACE
  23
  24 static CRYPTO_RWLOCK *trace_lock = NULL;
  25
  26 static 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  */
  37 static int trace_write(BIO *b, const char *buf,
  38                                size_t num, size_t *written);
  39 static int trace_puts(BIO *b, const char *str);
  40 static long trace_ctrl(BIO *channel, int cmd, long argl, void *argp);
  41 static int trace_free(BIO *b);
  42
  43 static 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
  58 struct trace_data_st {
  59     OSSL_trace_cb callback;
  60     int category;
  61     void *data;
  62 };
  63
  64 static 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_DURING,
  69                                ctx->data);
  70
  71     *written = cnt;
  72     return cnt != 0;
  73 }
  74
  75 static 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
  85 static 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
 101 static 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 */
 115 struct trace_category_st {
 116     const char * const name;
 117     const int num;
 118 };
 119 #define TRACE_CATEGORY_(name)       { #name, OSSL_TRACE_CATEGORY_##name }
 120
 121 static const struct trace_category_st trace_categories[] = {
 122     TRACE_CATEGORY_(ANY),
 123     TRACE_CATEGORY_(INIT),
 124     TRACE_CATEGORY_(TLS),
 125     TRACE_CATEGORY_(TLS_CIPHER),
 126     TRACE_CATEGORY_(ENGINE_CONF),
 127 };
 128
 129 const char *OSSL_trace_get_category_name(int num)
 130 {
 131     size_t i;
 132
 133     for (i = 0; i < OSSL_NELEM(trace_categories); i++)
 134         if (trace_categories[i].num == num)
 135             return trace_categories[i].name;
 136     return NULL; /* not found */
 137 }
 138
 139 int OSSL_trace_get_category_num(const char *name)
 140 {
 141     size_t i;
 142
 143     for (i = 0; i < OSSL_NELEM(trace_categories); i++)
 144         if (strcasecmp(name, trace_categories[i].name) == 0)
 145             return trace_categories[i].num;
 146     return -1; /* not found */
 147 }
 148
 149 #ifndef OPENSSL_NO_TRACE
 150
 151 /* We use one trace channel for each trace category */
 152 static struct {
 153     enum { t_channel, t_callback } type;
 154     BIO *bio;
 155     char *prefix;
 156     char *suffix;
 157 } trace_channels[OSSL_TRACE_CATEGORY_NUM] = {
 158     { 0, NULL, NULL, NULL },
 159 };
 160
 161 #endif
 162
 163 int ossl_trace_init(void)
 164 {
 165 #ifndef OPENSSL_NO_TRACE
 166     trace_lock = CRYPTO_THREAD_lock_new();
 167     if (trace_lock != NULL)
 168         return 1;
 169 #endif
 170
 171     return 0;
 172 }
 173
 174 void ossl_trace_cleanup(void)
 175 {
 176 #ifndef OPENSSL_NO_TRACE
 177     int category;
 178
 179     for (category = 0; category < OSSL_TRACE_CATEGORY_NUM; category++)
 180         OSSL_trace_set_channel(category, NULL);
 181     CRYPTO_THREAD_lock_free(trace_lock);
 182 #endif
 183 }
 184
 185 int OSSL_trace_set_channel(int category, BIO *channel)
 186 {
 187 #ifndef OPENSSL_NO_TRACE
 188     BIO *prev_channel;
 189
 190     if (category < 0 || category >= OSSL_TRACE_CATEGORY_NUM)
 191         goto err;
 192
 193     prev_channel = trace_channels[category].bio;
 194
 195     if (prev_channel != NULL) {
 196         BIO_free(prev_channel);
 197         trace_channels[category].bio = NULL;
 198     }
 199
 200     if (channel == NULL)
 201         return 1;                /* Done */
 202
 203     trace_channels[category].bio = channel;
 204     trace_channels[category].type = t_channel;
 205
 206     return 1;
 207
 208  err:
 209 #endif
 210
 211     return 0;
 212 }
 213
 214 int OSSL_trace_set_callback(int category, OSSL_trace_cb callback, void *data)
 215 {
 216 #ifndef OPENSSL_NO_TRACE
 217     BIO *channel = trace_channels[category].bio;
 218     struct trace_data_st *trace_data = NULL;
 219
 220     if (channel != NULL) {
 221         BIO_free(channel);
 222         trace_channels[category].bio = NULL;
 223     }
 224
 225     if (callback == NULL)
 226         return 1; /* done */
 227
 228     channel = BIO_new(&trace_method);
 229     if (channel == NULL)
 230         goto err;
 231
 232     trace_data = OPENSSL_zalloc(sizeof(struct trace_data_st));
 233     if (trace_data == NULL)
 234         goto err;
 235
 236     trace_data->callback = callback;
 237     trace_data->category = category;
 238     trace_data->data = data;
 239
 240     BIO_set_data(channel, trace_data);
 241
 242     trace_channels[category].bio = channel;
 243     trace_channels[category].type = t_callback;
 244
 245     return 1;
 246
 247  err:
 248     BIO_free(channel);
 249     OPENSSL_free(trace_data);
 250 #endif
 251
 252     return 0;
 253 }
 254
 255 int OSSL_trace_set_prefix(int category, const char *prefix)
 256 {
 257 #ifndef OPENSSL_NO_TRACE
 258     char *curr_prefix = trace_channels[category].prefix;
 259
 260     if (curr_prefix != NULL) {
 261         OPENSSL_free(curr_prefix);
 262         trace_channels[category].prefix = NULL;
 263     }
 264
 265     if (prefix == NULL)
 266         return 1;                /* Done */
 267
 268     curr_prefix = OPENSSL_strdup(prefix);
 269     if (curr_prefix == NULL)
 270         goto err;
 271
 272     trace_channels[category].prefix = curr_prefix;
 273
 274     return 1;
 275
 276  err:
 277 #endif
 278
 279     return 0;
 280 }
 281
 282 int OSSL_trace_set_suffix(int category, const char *suffix)
 283 {
 284 #ifndef OPENSSL_NO_TRACE
 285     char *curr_suffix = trace_channels[category].suffix;
 286
 287     if (curr_suffix != NULL) {
 288         OPENSSL_free(curr_suffix);
 289         trace_channels[category].suffix = NULL;
 290     }
 291
 292     if (suffix == NULL)
 293         return 1; /* done */
 294
 295     curr_suffix = OPENSSL_strdup(suffix);
 296     if (curr_suffix == NULL)
 297         goto err;
 298
 299     trace_channels[category].suffix = curr_suffix;
 300
 301     return 1;
 302
 303  err:
 304 #endif
 305
 306     return 0;
 307 }
 308
 309 #ifndef OPENSSL_NO_TRACE
 310 static int ossl_trace_get_category(int category)
 311 {
 312     if (category < 0 || category >= OSSL_TRACE_CATEGORY_NUM)
 313         return -1;
 314     if (trace_channels[category].bio != NULL)
 315         return category;
 316     return OSSL_TRACE_CATEGORY_ANY;
 317 }
 318 #endif
 319
 320 int OSSL_trace_enabled(int category)
 321 {
 322     int ret = 0;
 323 #ifndef OPENSSL_NO_TRACE
 324     category = ossl_trace_get_category(category);
 325     ret = trace_channels[category].bio != NULL;
 326 #endif
 327     return ret;
 328 }
 329
 330 BIO *OSSL_trace_begin(int category)
 331 {
 332     BIO *channel = NULL;
 333 #ifndef OPENSSL_NO_TRACE
 334     char *prefix = NULL;
 335
 336     category = ossl_trace_get_category(category);
 337     channel = trace_channels[category].bio;
 338     prefix = trace_channels[category].prefix;
 339
 340     if (channel != NULL) {
 341         CRYPTO_THREAD_write_lock(trace_lock);
 342         current_channel = channel;
 343         switch (trace_channels[category].type) {
 344         case t_channel:
 345             if (prefix != NULL) {
 346                 (void)BIO_puts(channel, prefix);
 347                 (void)BIO_puts(channel, "\n");
 348             }
 349             break;
 350         case t_callback:
 351             (void)BIO_ctrl(channel, OSSL_TRACE_CTRL_BEGIN,
 352                            prefix == NULL ? 0 : strlen(prefix), prefix);
 353             break;
 354         }
 355     }
 356 #endif
 357     return channel;
 358 }
 359
 360 void OSSL_trace_end(int category, BIO * channel)
 361 {
 362 #ifndef OPENSSL_NO_TRACE
 363     char *suffix = NULL;
 364
 365     category = ossl_trace_get_category(category);
 366     suffix = trace_channels[category].suffix;
 367     if (channel != NULL
 368         && ossl_assert(channel == current_channel)) {
 369         (void)BIO_flush(channel);
 370         switch (trace_channels[category].type) {
 371         case t_channel:
 372             if (suffix != NULL) {
 373                 (void)BIO_puts(channel, suffix);
 374                 (void)BIO_puts(channel, "\n");
 375             }
 376             break;
 377         case t_callback:
 378             (void)BIO_ctrl(channel, OSSL_TRACE_CTRL_END,
 379                            suffix == NULL ? 0 : strlen(suffix), suffix);
 380             break;
 381         }
 382         current_channel = NULL;
 383         CRYPTO_THREAD_unlock(trace_lock);
 384     }
 385 #endif
 386 }