tmk_core/tool/mbed/mbed-sdk/libraries/net/https/axTLS/ssl/loader.c

   1 /*
   2  * Copyright (c) 2007, Cameron Rich
   3  *
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are met:
   8  *
   9  * * Redistributions of source code must retain the above copyright notice,
  10  *   this list of conditions and the following disclaimer.
  11  * * Redistributions in binary form must reproduce the above copyright notice,
  12  *   this list of conditions and the following disclaimer in the documentation
  13  *   and/or other materials provided with the distribution.
  14  * * Neither the name of the axTLS project nor the names of its contributors
  15  *   may be used to endorse or promote products derived from this software
  16  *   without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  22  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  23  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  24  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  25  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  26  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  27  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  28  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 /**
  32  * Load certificates/keys into memory. These can be in many different formats.
  33  * PEM support and other formats can be processed here.
  34  *
  35  * The PEM private keys may be optionally encrypted with AES128 or AES256.
  36  * The encrypted PEM keys were generated with something like:
  37  *
  38  * openssl genrsa -aes128 -passout pass:abcd -out axTLS.key_aes128.pem 512
  39  */
  40
  41 #include <stdlib.h>
  42 #include <string.h>
  43 #include <stdio.h>
  44 #include "os_port.h"
  45 #include "ssl.h"
  46 #include "config.h"
  47
  48 static int do_obj(SSL_CTX *ssl_ctx, int obj_type,
  49                     SSLObjLoader *ssl_obj, const char *password);
  50 #ifdef CONFIG_SSL_HAS_PEM
  51 static int ssl_obj_PEM_load(SSL_CTX *ssl_ctx, int obj_type,
  52                         SSLObjLoader *ssl_obj, const char *password);
  53 #endif
  54
  55 /*
  56  * Load a file into memory that is in binary DER (or ascii PEM) format.
  57  */
  58 EXP_FUNC int STDCALL ssl_obj_load(SSL_CTX *ssl_ctx, int obj_type,
  59                             const char *filename, const char *password)
  60 {
  61 #ifndef CONFIG_SSL_SKELETON_MODE
  62     static const char * const begin = "-----BEGIN";
  63     int ret = SSL_OK;
  64     SSLObjLoader *ssl_obj = NULL;
  65
  66     if (filename == NULL)
  67     {
  68         ret = SSL_ERROR_INVALID_KEY;
  69         goto error;
  70     }
  71
  72     ssl_obj = (SSLObjLoader *)calloc(1, sizeof(SSLObjLoader));
  73     ssl_obj->len = get_file(filename, &ssl_obj->buf);
  74     if (ssl_obj->len <= 0)
  75     {
  76         ret = SSL_ERROR_INVALID_KEY;
  77         goto error;
  78     }
  79
  80     /* is the file a PEM file? */
  81     if (strstr((char *)ssl_obj->buf, begin) != NULL)
  82     {
  83 #ifdef CONFIG_SSL_HAS_PEM
  84         ret = ssl_obj_PEM_load(ssl_ctx, obj_type, ssl_obj, password);
  85 #else
  86         printf(unsupported_str);
  87         ret = SSL_ERROR_NOT_SUPPORTED;
  88 #endif
  89     }
  90     else
  91         ret = do_obj(ssl_ctx, obj_type, ssl_obj, password);
  92
  93 error:
  94     ssl_obj_free(ssl_obj);
  95     return ret;
  96 #else
  97     printf(unsupported_str);
  98     return SSL_ERROR_NOT_SUPPORTED;
  99 #endif /* CONFIG_SSL_SKELETON_MODE */
 100 }
 101
 102 /*
 103  * Transfer binary data into the object loader.
 104  */
 105 EXP_FUNC int STDCALL ssl_obj_memory_load(SSL_CTX *ssl_ctx, int mem_type,
 106         const uint8_t *data, int len, const char *password)
 107 {
 108     int ret;
 109     SSLObjLoader ssl_obj;
 110     ssl_obj.buf = data;
 111     ssl_obj.len = len;
 112     ret = do_obj(ssl_ctx, mem_type, &ssl_obj, password);
 113
 114     return ret;
 115 }
 116
 117 /*
 118  * Actually work out what we are doing
 119  */
 120 static int do_obj(SSL_CTX *ssl_ctx, int obj_type,
 121                     SSLObjLoader *ssl_obj, const char *password)
 122 {
 123     int ret = SSL_OK;
 124
 125     switch (obj_type)
 126     {
 127         case SSL_OBJ_RSA_KEY:
 128             ret = add_private_key(ssl_ctx, ssl_obj);
 129             break;
 130
 131         case SSL_OBJ_X509_CERT:
 132             ret = add_cert(ssl_ctx, ssl_obj->buf, ssl_obj->len);
 133             break;
 134
 135 #ifdef CONFIG_SSL_CERT_VERIFICATION
 136         case SSL_OBJ_X509_CACERT:
 137             add_cert_auth(ssl_ctx, ssl_obj->buf, ssl_obj->len);
 138             break;
 139 #endif
 140
 141 #ifdef CONFIG_SSL_USE_PKCS12
 142         case SSL_OBJ_PKCS8:
 143             ret = pkcs8_decode(ssl_ctx, ssl_obj, password);
 144             break;
 145
 146         case SSL_OBJ_PKCS12:
 147             ret = pkcs12_decode(ssl_ctx, ssl_obj, password);
 148             break;
 149 #endif
 150         default:
 151             printf(unsupported_str);
 152             ret = SSL_ERROR_NOT_SUPPORTED;
 153             break;
 154     }
 155
 156     return ret;
 157 }
 158
 159 /*
 160  * Clean up our mess.
 161  */
 162 void ssl_obj_free(SSLObjLoader *ssl_obj)
 163 {
 164     if (ssl_obj)
 165     {
 166         free(ssl_obj->buf);
 167         free(ssl_obj);
 168     }
 169 }
 170
 171 /*
 172  * Support for PEM encoded keys/certificates.
 173  */
 174 #ifdef CONFIG_SSL_HAS_PEM
 175
 176 #define NUM_PEM_TYPES               4
 177 #define IV_SIZE                     16
 178 #define IS_RSA_PRIVATE_KEY          0
 179 #define IS_ENCRYPTED_PRIVATE_KEY    1
 180 #define IS_PRIVATE_KEY              2
 181 #define IS_CERTIFICATE              3
 182
 183 static const char * const begins[NUM_PEM_TYPES] =
 184 {
 185     "-----BEGIN RSA PRIVATE KEY-----",
 186     "-----BEGIN ENCRYPTED PRIVATE KEY-----",
 187     "-----BEGIN PRIVATE KEY-----",
 188     "-----BEGIN CERTIFICATE-----",
 189 };
 190
 191 static const char * const ends[NUM_PEM_TYPES] =
 192 {
 193     "-----END RSA PRIVATE KEY-----",
 194     "-----END ENCRYPTED PRIVATE KEY-----",
 195     "-----END PRIVATE KEY-----",
 196     "-----END CERTIFICATE-----",
 197 };
 198
 199 static const char * const aes_str[2] =
 200 {
 201     "DEK-Info: AES-128-CBC,",
 202     "DEK-Info: AES-256-CBC,"
 203 };
 204
 205 /**
 206  * Take a base64 blob of data and decrypt it (using AES) into its
 207  * proper ASN.1 form.
 208  */
 209 static int pem_decrypt(const char *where, const char *end,
 210                         const char *password, SSLObjLoader *ssl_obj)
 211 {
 212     int ret = -1;
 213     int is_aes_256 = 0;
 214     char *start = NULL;
 215     uint8_t iv[IV_SIZE];
 216     int i, pem_size;
 217     MD5_CTX md5_ctx;
 218     AES_CTX aes_ctx;
 219     uint8_t key[32];        /* AES256 size */
 220
 221     if (password == NULL || strlen(password) == 0)
 222     {
 223 #ifdef CONFIG_SSL_FULL_MODE
 224         printf("Error: Need a password for this PEM file\n"); TTY_FLUSH();
 225 #endif
 226         goto error;
 227     }
 228
 229     if ((start = strstr((const char *)where, aes_str[0])))         /* AES128? */
 230     {
 231         start += strlen(aes_str[0]);
 232     }
 233     else if ((start = strstr((const char *)where, aes_str[1])))    /* AES256? */
 234     {
 235         is_aes_256 = 1;
 236         start += strlen(aes_str[1]);
 237     }
 238     else
 239     {
 240 #ifdef CONFIG_SSL_FULL_MODE
 241         printf("Error: Unsupported password cipher\n"); TTY_FLUSH();
 242 #endif
 243         goto error;
 244     }
 245
 246     /* convert from hex to binary - assumes uppercase hex */
 247     for (i = 0; i < IV_SIZE; i++)
 248     {
 249         char c = *start++ - '0';
 250         iv[i] = (c > 9 ? c + '0' - 'A' + 10 : c) << 4;
 251         c = *start++ - '0';
 252         iv[i] += (c > 9 ? c + '0' - 'A' + 10 : c);
 253     }
 254
 255     while (*start == '\r' || *start == '\n')
 256         start++;
 257
 258     /* turn base64 into binary */
 259     pem_size = (int)(end-start);
 260     if (base64_decode(start, pem_size, ssl_obj->buf, &ssl_obj->len) != 0)
 261         goto error;
 262
 263     /* work out the key */
 264     MD5_Init(&md5_ctx);
 265     MD5_Update(&md5_ctx, (const uint8_t *)password, strlen(password));
 266     MD5_Update(&md5_ctx, iv, SALT_SIZE);
 267     MD5_Final(key, &md5_ctx);
 268
 269     if (is_aes_256)
 270     {
 271         MD5_Init(&md5_ctx);
 272         MD5_Update(&md5_ctx, key, MD5_SIZE);
 273         MD5_Update(&md5_ctx, (const uint8_t *)password, strlen(password));
 274         MD5_Update(&md5_ctx, iv, SALT_SIZE);
 275         MD5_Final(&key[MD5_SIZE], &md5_ctx);
 276     }
 277
 278     /* decrypt using the key/iv */
 279     AES_set_key(&aes_ctx, key, iv, is_aes_256 ? AES_MODE_256 : AES_MODE_128);
 280     AES_convert_key(&aes_ctx);
 281     AES_cbc_decrypt(&aes_ctx, ssl_obj->buf, ssl_obj->buf, ssl_obj->len);
 282     ret = 0;
 283
 284 error:
 285     return ret;
 286 }
 287
 288 /**
 289  * Take a base64 blob of data and turn it into its proper ASN.1 form.
 290  */
 291 static int new_pem_obj(SSL_CTX *ssl_ctx, int is_cacert, char *where,
 292                     int remain, const char *password)
 293 {
 294     int ret = SSL_ERROR_BAD_CERTIFICATE;
 295     SSLObjLoader *ssl_obj = NULL;
 296
 297     while (remain > 0)
 298     {
 299         int i, pem_size, obj_type;
 300         char *start = NULL, *end = NULL;
 301
 302         for (i = 0; i < NUM_PEM_TYPES; i++)
 303         {
 304             if ((start = strstr(where, begins[i])) &&
 305                     (end = strstr(where, ends[i])))
 306             {
 307                 remain -= (int)(end-where);
 308                 start += strlen(begins[i]);
 309                 pem_size = (int)(end-start);
 310
 311                 ssl_obj = (SSLObjLoader *)calloc(1, sizeof(SSLObjLoader));
 312
 313                 /* 4/3 bigger than what we need but so what */
 314                 ssl_obj->buf = (uint8_t *)calloc(1, pem_size);
 315                 ssl_obj->len = pem_size;
 316
 317                 if (i == IS_RSA_PRIVATE_KEY &&
 318                             strstr(start, "Proc-Type:") &&
 319                             strstr(start, "4,ENCRYPTED"))
 320                 {
 321                     /* check for encrypted PEM file */
 322                     if (pem_decrypt(start, end, password, ssl_obj) < 0)
 323                     {
 324                         ret = SSL_ERROR_BAD_CERTIFICATE;
 325                         goto error;
 326                     }
 327                 }
 328                 else
 329                 {
 330                     ssl_obj->len = pem_size;
 331                     if (base64_decode(start, pem_size,
 332                                 ssl_obj->buf, &ssl_obj->len) != 0)
 333                     {
 334                         ret = SSL_ERROR_BAD_CERTIFICATE;
 335                         goto error;
 336                     }
 337                 }
 338
 339                 switch (i)
 340                 {
 341                     case IS_RSA_PRIVATE_KEY:
 342                         obj_type = SSL_OBJ_RSA_KEY;
 343                         break;
 344
 345                     case IS_ENCRYPTED_PRIVATE_KEY:
 346                     case IS_PRIVATE_KEY:
 347                         obj_type = SSL_OBJ_PKCS8;
 348                         break;
 349
 350                     case IS_CERTIFICATE:
 351                         obj_type = is_cacert ?
 352                                         SSL_OBJ_X509_CACERT : SSL_OBJ_X509_CERT;
 353                         break;
 354
 355                     default:
 356                         ret = SSL_ERROR_BAD_CERTIFICATE;
 357                         goto error;
 358                 }
 359
 360                 /* In a format we can now understand - so process it */
 361                 if ((ret = do_obj(ssl_ctx, obj_type, ssl_obj, password)))
 362                     goto error;
 363
 364                 end += strlen(ends[i]);
 365                 remain -= strlen(ends[i]);
 366                 while (remain > 0 && (*end == '\r' || *end == '\n'))
 367                 {
 368                     end++;
 369                     remain--;
 370                 }
 371
 372                 where = end;
 373                 break;
 374             }
 375         }
 376
 377         ssl_obj_free(ssl_obj);
 378         ssl_obj = NULL;
 379         if (start == NULL)
 380            break;
 381     }
 382 error:
 383     ssl_obj_free(ssl_obj);
 384     return ret;
 385 }
 386
 387 /*
 388  * Load a file into memory that is in ASCII PEM format.
 389  */
 390 static int ssl_obj_PEM_load(SSL_CTX *ssl_ctx, int obj_type,
 391                         SSLObjLoader *ssl_obj, const char *password)
 392 {
 393     char *start;
 394
 395     /* add a null terminator */
 396     ssl_obj->len++;
 397     ssl_obj->buf = (uint8_t *)realloc(ssl_obj->buf, ssl_obj->len);
 398     ssl_obj->buf[ssl_obj->len-1] = 0;
 399     start = (char *)ssl_obj->buf;
 400     return new_pem_obj(ssl_ctx, obj_type == SSL_OBJ_X509_CACERT,
 401                                 start, ssl_obj->len, password);
 402 }
 403 #endif /* CONFIG_SSL_HAS_PEM */
 404
 405 /**
 406  * Load the key/certificates in memory depending on compile-time and user
 407  * options.
 408  */
 409 int load_key_certs(SSL_CTX *ssl_ctx)
 410 {
 411     int ret = SSL_OK;
 412     uint32_t options = ssl_ctx->options;
 413 #ifdef CONFIG_SSL_GENERATE_X509_CERT
 414     uint8_t *cert_data = NULL;
 415     int cert_size;
 416     static const char *dn[] =
 417     {
 418         CONFIG_SSL_X509_COMMON_NAME,
 419         CONFIG_SSL_X509_ORGANIZATION_NAME,
 420         CONFIG_SSL_X509_ORGANIZATION_UNIT_NAME
 421     };
 422 #endif
 423
 424     /* do the private key first */
 425     if (strlen(CONFIG_SSL_PRIVATE_KEY_LOCATION) > 0)
 426     {
 427         if ((ret = ssl_obj_load(ssl_ctx, SSL_OBJ_RSA_KEY,
 428                                 CONFIG_SSL_PRIVATE_KEY_LOCATION,
 429                                 CONFIG_SSL_PRIVATE_KEY_PASSWORD)) < 0)
 430             goto error;
 431     }
 432     else if (!(options & SSL_NO_DEFAULT_KEY))
 433     {
 434 #if defined(CONFIG_SSL_USE_DEFAULT_KEY) || defined(CONFIG_SSL_SKELETON_MODE)
 435 //        static const    /* saves a few more bytes */
 436 //#include "private_key.h"
 437 //       ssl_obj_memory_load(ssl_ctx, SSL_OBJ_RSA_KEY, default_private_key,
 438   //              default_private_key_len, NULL);
 439 #endif
 440     }
 441
 442     /* now load the certificate */
 443 #ifdef CONFIG_SSL_GENERATE_X509_CERT
 444     if ((cert_size = ssl_x509_create(ssl_ctx, 0, dn, &cert_data)) < 0)
 445     {
 446         ret = cert_size;
 447         goto error;
 448     }
 449
 450     ssl_obj_memory_load(ssl_ctx, SSL_OBJ_X509_CERT, cert_data, cert_size, NULL);
 451     free(cert_data);
 452 #else
 453     if (strlen(CONFIG_SSL_X509_CERT_LOCATION))
 454     {
 455         if ((ret = ssl_obj_load(ssl_ctx, SSL_OBJ_X509_CERT,
 456                                 CONFIG_SSL_X509_CERT_LOCATION, NULL)) < 0)
 457             goto error;
 458     }
 459     else if (!(options & SSL_NO_DEFAULT_KEY))
 460     {
 461 #if defined(CONFIG_SSL_USE_DEFAULT_KEY) || defined(CONFIG_SSL_SKELETON_MODE)
 462         static const    /* saves a few bytes and RAM */
 463 #include "cert.h"
 464         ssl_obj_memory_load(ssl_ctx, SSL_OBJ_X509_CERT,
 465                     default_certificate, default_certificate_len, NULL);
 466 #endif
 467     }
 468 #endif
 469
 470 error:
 471 #ifdef CONFIG_SSL_FULL_MODE
 472     if (ret)
 473     {
 474         printf("Error: Certificate or key not loaded\n"); TTY_FLUSH();
 475     }
 476 #endif
 477
 478     return ret;
 479
 480 }