crypto/encode_decode/encoder_lib.c

   1 /*
   2  * Copyright 2019-2021 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 "e_os.h"                /* strcasecmp on Windows */
  11 #include <openssl/core_names.h>
  12 #include <openssl/bio.h>
  13 #include <openssl/encoder.h>
  14 #include <openssl/buffer.h>
  15 #include <openssl/params.h>
  16 #include <openssl/provider.h>
  17 #include <openssl/trace.h>
  18 #include "internal/bio.h"
  19 #include "encoder_local.h"
  20
  21 struct encoder_process_data_st {
  22     OSSL_ENCODER_CTX *ctx;
  23
  24     /* Current BIO */
  25     BIO *bio;
  26
  27     /* Index of the current encoder instance to be processed */
  28     int current_encoder_inst_index;
  29
  30     /* Processing data passed down through recursion */
  31     int level;                   /* Recursion level */
  32     OSSL_ENCODER_INSTANCE *next_encoder_inst;
  33     int count_output_structure;
  34
  35     /* Processing data passed up through recursion */
  36     OSSL_ENCODER_INSTANCE *prev_encoder_inst;
  37     unsigned char *running_output;
  38     size_t running_output_length;
  39 };
  40
  41 static int encoder_process(struct encoder_process_data_st *data);
  42
  43 int OSSL_ENCODER_to_bio(OSSL_ENCODER_CTX *ctx, BIO *out)
  44 {
  45     struct encoder_process_data_st data;
  46
  47     memset(&data, 0, sizeof(data));
  48     data.ctx = ctx;
  49     data.bio = out;
  50     data.current_encoder_inst_index = OSSL_ENCODER_CTX_get_num_encoders(ctx);
  51
  52     return encoder_process(&data) > 0;
  53 }
  54
  55 #ifndef OPENSSL_NO_STDIO
  56 static BIO *bio_from_file(FILE *fp)
  57 {
  58     BIO *b;
  59
  60     if ((b = BIO_new(BIO_s_file())) == NULL) {
  61         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_BUF_LIB);
  62         return NULL;
  63     }
  64     BIO_set_fp(b, fp, BIO_NOCLOSE);
  65     return b;
  66 }
  67
  68 int OSSL_ENCODER_to_fp(OSSL_ENCODER_CTX *ctx, FILE *fp)
  69 {
  70     BIO *b = bio_from_file(fp);
  71     int ret = 0;
  72
  73     if (b != NULL)
  74         ret = OSSL_ENCODER_to_bio(ctx, b);
  75
  76     BIO_free(b);
  77     return ret;
  78 }
  79 #endif
  80
  81 int OSSL_ENCODER_to_data(OSSL_ENCODER_CTX *ctx, unsigned char **pdata,
  82                          size_t *pdata_len)
  83 {
  84     BIO *out = BIO_new(BIO_s_mem());
  85     BUF_MEM *buf = NULL;
  86     int ret = 0;
  87
  88     if (pdata_len == NULL) {
  89         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
  90         return 0;
  91     }
  92
  93     if (OSSL_ENCODER_to_bio(ctx, out)
  94         && BIO_get_mem_ptr(out, &buf) > 0) {
  95         ret = 1; /* Hope for the best. A too small buffer will clear this */
  96
  97         if (pdata != NULL && *pdata != NULL) {
  98             if (*pdata_len < buf->length)
  99                 /*
 100                  * It's tempting to do |*pdata_len = (size_t)buf->length|
 101                  * However, it's believed to be confusing more than helpful,
 102                  * so we don't.
 103                  */
 104                 ret = 0;
 105             else
 106                 *pdata_len -= buf->length;
 107         } else {
 108             /* The buffer with the right size is already allocated for us */
 109             *pdata_len = (size_t)buf->length;
 110         }
 111
 112         if (ret) {
 113             if (pdata != NULL) {
 114                 if (*pdata != NULL) {
 115                     memcpy(*pdata, buf->data, buf->length);
 116                     *pdata += buf->length;
 117                 } else {
 118                     /* In this case, we steal the data from BIO_s_mem() */
 119                     *pdata = (unsigned char *)buf->data;
 120                     buf->data = NULL;
 121                 }
 122             }
 123         }
 124     }
 125     BIO_free(out);
 126     return ret;
 127 }
 128
 129 int OSSL_ENCODER_CTX_set_selection(OSSL_ENCODER_CTX *ctx, int selection)
 130 {
 131     if (!ossl_assert(ctx != NULL)) {
 132         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
 133         return 0;
 134     }
 135
 136     if (!ossl_assert(selection != 0)) {
 137         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_INVALID_ARGUMENT);
 138         return 0;
 139     }
 140
 141     ctx->selection = selection;
 142     return 1;
 143 }
 144
 145 int OSSL_ENCODER_CTX_set_output_type(OSSL_ENCODER_CTX *ctx,
 146                                      const char *output_type)
 147 {
 148     if (!ossl_assert(ctx != NULL) || !ossl_assert(output_type != NULL)) {
 149         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
 150         return 0;
 151     }
 152
 153     ctx->output_type = output_type;
 154     return 1;
 155 }
 156
 157 int OSSL_ENCODER_CTX_set_output_structure(OSSL_ENCODER_CTX *ctx,
 158                                           const char *output_structure)
 159 {
 160     if (!ossl_assert(ctx != NULL) || !ossl_assert(output_structure != NULL)) {
 161         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
 162         return 0;
 163     }
 164
 165     ctx->output_structure = output_structure;
 166     return 1;
 167 }
 168
 169 static OSSL_ENCODER_INSTANCE *ossl_encoder_instance_new(OSSL_ENCODER *encoder,
 170                                                         void *encoderctx)
 171 {
 172     OSSL_ENCODER_INSTANCE *encoder_inst = NULL;
 173     OSSL_PARAM params[4];
 174
 175     if (!ossl_assert(encoder != NULL)) {
 176         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
 177         return 0;
 178     }
 179
 180     if (encoder->get_params == NULL) {
 181         ERR_raise(ERR_LIB_OSSL_ENCODER,
 182                   OSSL_ENCODER_R_MISSING_GET_PARAMS);
 183         return 0;
 184     }
 185
 186     if ((encoder_inst = OPENSSL_zalloc(sizeof(*encoder_inst))) == NULL) {
 187         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_MALLOC_FAILURE);
 188         return 0;
 189     }
 190
 191     /*
 192      * Cache the input and output types for this encoder.  The output type
 193      * is mandatory.
 194      */
 195     params[0] =
 196         OSSL_PARAM_construct_utf8_ptr(OSSL_ENCODER_PARAM_OUTPUT_TYPE,
 197                                       (char **)&encoder_inst->output_type, 0);
 198     params[1] =
 199         OSSL_PARAM_construct_utf8_ptr(OSSL_ENCODER_PARAM_OUTPUT_STRUCTURE,
 200                                       (char **)&encoder_inst->output_structure,
 201                                       0);
 202     params[2] =
 203         OSSL_PARAM_construct_utf8_ptr(OSSL_ENCODER_PARAM_INPUT_TYPE,
 204                                       (char **)&encoder_inst->input_type, 0);
 205     params[3] = OSSL_PARAM_construct_end();
 206
 207     if (!encoder->get_params(params)
 208         || !OSSL_PARAM_modified(&params[0]))
 209         goto err;
 210
 211     if (!OSSL_ENCODER_up_ref(encoder)) {
 212         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_INTERNAL_ERROR);
 213         goto err;
 214     }
 215
 216     encoder_inst->encoder = encoder;
 217     encoder_inst->encoderctx = encoderctx;
 218     return encoder_inst;
 219  err:
 220     ossl_encoder_instance_free(encoder_inst);
 221     return NULL;
 222 }
 223
 224 void ossl_encoder_instance_free(OSSL_ENCODER_INSTANCE *encoder_inst)
 225 {
 226     if (encoder_inst != NULL) {
 227         if (encoder_inst->encoder != NULL)
 228             encoder_inst->encoder->freectx(encoder_inst->encoderctx);
 229         encoder_inst->encoderctx = NULL;
 230         OSSL_ENCODER_free(encoder_inst->encoder);
 231         encoder_inst->encoder = NULL;
 232         OPENSSL_free(encoder_inst);
 233     }
 234 }
 235
 236 static int ossl_encoder_ctx_add_encoder_inst(OSSL_ENCODER_CTX *ctx,
 237                                              OSSL_ENCODER_INSTANCE *ei)
 238 {
 239     int ok;
 240
 241     if (ctx->encoder_insts == NULL
 242         && (ctx->encoder_insts =
 243             sk_OSSL_ENCODER_INSTANCE_new_null()) == NULL) {
 244         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_MALLOC_FAILURE);
 245         return 0;
 246     }
 247
 248     ok = (sk_OSSL_ENCODER_INSTANCE_push(ctx->encoder_insts, ei) > 0);
 249     if (ok) {
 250         OSSL_TRACE_BEGIN(ENCODER) {
 251             BIO_printf(trc_out,
 252                        "(ctx %p) Added encoder instance %p (encoder %p) with:\n",
 253                        (void *)ctx, (void *)ei, (void *)ei->encoder);
 254             BIO_printf(trc_out,
 255                        "    output type: %s, output structure: %s, input type :%s\n",
 256                        ei->output_type, ei->output_structure, ei->input_type);
 257         } OSSL_TRACE_END(ENCODER);
 258     }
 259     return ok;
 260 }
 261
 262 int OSSL_ENCODER_CTX_add_encoder(OSSL_ENCODER_CTX *ctx, OSSL_ENCODER *encoder)
 263 {
 264     OSSL_ENCODER_INSTANCE *encoder_inst = NULL;
 265     const OSSL_PROVIDER *prov = NULL;
 266     void *encoderctx = NULL;
 267     void *provctx = NULL;
 268
 269     if (!ossl_assert(ctx != NULL) || !ossl_assert(encoder != NULL)) {
 270         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
 271         return 0;
 272     }
 273
 274     prov = OSSL_ENCODER_provider(encoder);
 275     provctx = OSSL_PROVIDER_get0_provider_ctx(prov);
 276
 277     if ((encoderctx = encoder->newctx(provctx)) == NULL
 278         || (encoder_inst =
 279             ossl_encoder_instance_new(encoder, encoderctx)) == NULL)
 280         goto err;
 281     /* Avoid double free of encoderctx on further errors */
 282     encoderctx = NULL;
 283
 284     if (!ossl_encoder_ctx_add_encoder_inst(ctx, encoder_inst))
 285         goto err;
 286
 287     return 1;
 288  err:
 289     ossl_encoder_instance_free(encoder_inst);
 290     if (encoderctx != NULL)
 291         encoder->freectx(encoderctx);
 292     return 0;
 293 }
 294
 295 int OSSL_ENCODER_CTX_add_extra(OSSL_ENCODER_CTX *ctx,
 296                                OSSL_LIB_CTX *libctx, const char *propq)
 297 {
 298     return 1;
 299 }
 300
 301 int OSSL_ENCODER_CTX_get_num_encoders(OSSL_ENCODER_CTX *ctx)
 302 {
 303     if (ctx == NULL || ctx->encoder_insts == NULL)
 304         return 0;
 305     return sk_OSSL_ENCODER_INSTANCE_num(ctx->encoder_insts);
 306 }
 307
 308 int OSSL_ENCODER_CTX_set_construct(OSSL_ENCODER_CTX *ctx,
 309                                    OSSL_ENCODER_CONSTRUCT *construct)
 310 {
 311     if (!ossl_assert(ctx != NULL)) {
 312         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
 313         return 0;
 314     }
 315     ctx->construct = construct;
 316     return 1;
 317 }
 318
 319 int OSSL_ENCODER_CTX_set_construct_data(OSSL_ENCODER_CTX *ctx,
 320                                         void *construct_data)
 321 {
 322     if (!ossl_assert(ctx != NULL)) {
 323         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
 324         return 0;
 325     }
 326     ctx->construct_data = construct_data;
 327     return 1;
 328 }
 329
 330 int OSSL_ENCODER_CTX_set_cleanup(OSSL_ENCODER_CTX *ctx,
 331                                  OSSL_ENCODER_CLEANUP *cleanup)
 332 {
 333     if (!ossl_assert(ctx != NULL)) {
 334         ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_PASSED_NULL_PARAMETER);
 335         return 0;
 336     }
 337     ctx->cleanup = cleanup;
 338     return 1;
 339 }
 340
 341 OSSL_ENCODER *
 342 OSSL_ENCODER_INSTANCE_get_encoder(OSSL_ENCODER_INSTANCE *encoder_inst)
 343 {
 344     if (encoder_inst == NULL)
 345         return NULL;
 346     return encoder_inst->encoder;
 347 }
 348
 349 void *
 350 OSSL_ENCODER_INSTANCE_get_encoder_ctx(OSSL_ENCODER_INSTANCE *encoder_inst)
 351 {
 352     if (encoder_inst == NULL)
 353         return NULL;
 354     return encoder_inst->encoderctx;
 355 }
 356
 357 const char *
 358 OSSL_ENCODER_INSTANCE_get_input_type(OSSL_ENCODER_INSTANCE *encoder_inst)
 359 {
 360     if (encoder_inst == NULL)
 361         return NULL;
 362     return encoder_inst->input_type;
 363 }
 364
 365 const char *
 366 OSSL_ENCODER_INSTANCE_get_output_type(OSSL_ENCODER_INSTANCE *encoder_inst)
 367 {
 368     if (encoder_inst == NULL)
 369         return NULL;
 370     return encoder_inst->output_type;
 371 }
 372
 373 const char *
 374 OSSL_ENCODER_INSTANCE_get_output_structure(OSSL_ENCODER_INSTANCE *encoder_inst)
 375 {
 376     if (encoder_inst == NULL)
 377         return NULL;
 378     return encoder_inst->output_structure;
 379 }
 380
 381 static int encoder_process(struct encoder_process_data_st *data)
 382 {
 383     OSSL_ENCODER_INSTANCE *current_encoder_inst = NULL;
 384     OSSL_ENCODER *current_encoder = NULL;
 385     OSSL_ENCODER_CTX *current_encoder_ctx = NULL;
 386     BIO *allocated_out = NULL;
 387     const void *original_data = NULL;
 388     OSSL_PARAM abstract[10];
 389     const OSSL_PARAM *current_abstract = NULL;
 390     int i;
 391     int ok = -1;  /* -1 signifies that the lookup loop gave nothing */
 392     int top = 0;
 393
 394     if (data->next_encoder_inst == NULL) {
 395         /* First iteration, where we prepare for what is to come */
 396
 397         data->count_output_structure =
 398             data->ctx->output_structure == NULL ? -1 : 0;
 399         top = 1;
 400     }
 401
 402     for (i = data->current_encoder_inst_index; i-- > 0;) {
 403         OSSL_ENCODER *next_encoder = NULL;
 404         const char *current_output_type;
 405         const char *current_output_structure;
 406         struct encoder_process_data_st new_data;
 407
 408         if (!top)
 409             next_encoder =
 410                 OSSL_ENCODER_INSTANCE_get_encoder(data->next_encoder_inst);
 411
 412         current_encoder_inst =
 413             sk_OSSL_ENCODER_INSTANCE_value(data->ctx->encoder_insts, i);
 414         current_encoder =
 415             OSSL_ENCODER_INSTANCE_get_encoder(current_encoder_inst);
 416         current_encoder_ctx =
 417             OSSL_ENCODER_INSTANCE_get_encoder_ctx(current_encoder_inst);
 418         current_output_type =
 419             OSSL_ENCODER_INSTANCE_get_output_type(current_encoder_inst);
 420         current_output_structure =
 421             OSSL_ENCODER_INSTANCE_get_output_structure(current_encoder_inst);
 422         memset(&new_data, 0, sizeof(new_data));
 423         new_data.ctx = data->ctx;
 424         new_data.current_encoder_inst_index = i;
 425         new_data.next_encoder_inst = current_encoder_inst;
 426         new_data.count_output_structure = data->count_output_structure;
 427         new_data.level = data->level + 1;
 428
 429         OSSL_TRACE_BEGIN(ENCODER) {
 430             BIO_printf(trc_out,
 431                        "[%d] (ctx %p) Considering encoder instance %p (encoder %p)\n",
 432                        data->level, (void *)data->ctx,
 433                        (void *)current_encoder_inst, (void *)current_encoder);
 434         } OSSL_TRACE_END(ENCODER);
 435
 436         /*
 437          * If this is the top call, we check if the output type of the current
 438          * encoder matches the desired output type.
 439          * If this isn't the top call, i.e. this is deeper in the recursion,
 440          * we instead check if the output type of the current encoder matches
 441          * the name of the next encoder (the one found by the parent call).
 442          */
 443         if (top) {
 444             if (data->ctx->output_type != NULL
 445                 && strcasecmp(current_output_type,
 446                               data->ctx->output_type) != 0) {
 447                 OSSL_TRACE_BEGIN(ENCODER) {
 448                     BIO_printf(trc_out,
 449                                "[%d]    Skipping because current encoder output type (%s) != desired output type (%s)\n",
 450                                data->level,
 451                                current_output_type, data->ctx->output_type);
 452                 } OSSL_TRACE_END(ENCODER);
 453                 continue;
 454             }
 455         } else {
 456             if (!OSSL_ENCODER_is_a(next_encoder, current_output_type)) {
 457                 OSSL_TRACE_BEGIN(ENCODER) {
 458                     BIO_printf(trc_out,
 459                                "[%d]    Skipping because current encoder output type (%s) != name of encoder %p\n",
 460                                data->level,
 461                                current_output_type, (void *)next_encoder);
 462                 } OSSL_TRACE_END(ENCODER);
 463                 continue;
 464             }
 465         }
 466
 467         /*
 468          * If the caller and the current encoder specify an output structure,
 469          * Check if they match.  If they do, count the match, otherwise skip
 470          * the current encoder.
 471          */
 472         if (data->ctx->output_structure != NULL
 473             && current_output_structure != NULL) {
 474             if (strcasecmp(data->ctx->output_structure,
 475                            current_output_structure) != 0) {
 476                 OSSL_TRACE_BEGIN(ENCODER) {
 477                     BIO_printf(trc_out,
 478                                "[%d]    Skipping because current encoder output structure (%s) != ctx output structure (%s)\n",
 479                                data->level,
 480                                current_output_structure,
 481                                data->ctx->output_structure);
 482                 } OSSL_TRACE_END(ENCODER);
 483                 continue;
 484             }
 485
 486             data->count_output_structure++;
 487         }
 488
 489         /*
 490          * Recurse to process the encoder implementations before the current
 491          * one.
 492          */
 493         ok = encoder_process(&new_data);
 494
 495         data->prev_encoder_inst = new_data.prev_encoder_inst;
 496         data->running_output = new_data.running_output;
 497         data->running_output_length = new_data.running_output_length;
 498
 499         /*
 500          * ok == -1     means that the recursion call above gave no further
 501          *              encoders, and that the one we're currently at should
 502          *              be tried.
 503          * ok == 0      means that something failed in the recursion call
 504          *              above, making the result unsuitable for a chain.
 505          *              In this case, we simply continue to try finding a
 506          *              suitable encoder at this recursion level.
 507          * ok == 1      means that the recursion call was successful, and we
 508          *              try to use the result at this recursion level.
 509          */
 510         if (ok != 0)
 511             break;
 512
 513         OSSL_TRACE_BEGIN(ENCODER) {
 514             BIO_printf(trc_out,
 515                        "[%d]    Skipping because recusion level %d failed\n",
 516                        data->level, new_data.level);
 517         } OSSL_TRACE_END(ENCODER);
 518     }
 519
 520     /*
 521      * If |i < 0|, we didn't find any useful encoder in this recursion, so
 522      * we do the rest of the process only if |i >= 0|.
 523      */
 524     if (i < 0) {
 525         ok = -1;
 526
 527         OSSL_TRACE_BEGIN(ENCODER) {
 528             BIO_printf(trc_out,
 529                        "[%d] (ctx %p) No suitable encoder found\n",
 530                        data->level, (void *)data->ctx);
 531         } OSSL_TRACE_END(ENCODER);
 532     } else {
 533         /* Preparations */
 534
 535         switch (ok) {
 536         case 0:
 537             break;
 538         case -1:
 539             /*
 540              * We have reached the beginning of the encoder instance sequence,
 541              * so we prepare the object to be encoded.
 542              */
 543
 544             /*
 545              * |data->count_output_structure| is one of these values:
 546              *
 547              * -1       There is no desired output structure
 548              *  0       There is a desired output structure, and it wasn't
 549              *          matched by any of the encoder instances that were
 550              *          considered
 551              * >0       There is a desired output structure, and at least one
 552              *          of the encoder instances matched it
 553              */
 554             if (data->count_output_structure == 0)
 555                 return 0;
 556
 557             original_data =
 558                 data->ctx->construct(current_encoder_inst,
 559                                      data->ctx->construct_data);
 560
 561             /* Assume that the constructor recorded an error */
 562             if (original_data != NULL)
 563                 ok = 1;
 564             else
 565                 ok = 0;
 566             break;
 567         case 1:
 568             if (!ossl_assert(data->running_output != NULL)) {
 569                 ERR_raise(ERR_LIB_OSSL_ENCODER, ERR_R_INTERNAL_ERROR);
 570                 ok = 0;
 571                 break;
 572             }
 573
 574             {
 575                 /*
 576                  * Create an object abstraction from the latest output, which
 577                  * was stolen from the previous round.
 578                  */
 579
 580                 OSSL_PARAM *abstract_p = abstract;
 581                 const char *prev_input_type =
 582                     OSSL_ENCODER_INSTANCE_get_input_type(data->prev_encoder_inst);
 583                 const char *prev_output_structure =
 584                     OSSL_ENCODER_INSTANCE_get_output_structure(data->prev_encoder_inst);
 585
 586                 if (prev_input_type != NULL)
 587                     *abstract_p++ =
 588                         OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_TYPE,
 589                                                          (char *)prev_input_type, 0);
 590                 if (prev_output_structure != NULL)
 591                     *abstract_p++ =
 592                         OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_STRUCTURE,
 593                                                          (char *)prev_output_structure,
 594                                                          0);
 595                 *abstract_p++ =
 596                     OSSL_PARAM_construct_octet_string(OSSL_OBJECT_PARAM_DATA,
 597                                                       data->running_output,
 598                                                       data->running_output_length);
 599                 *abstract_p = OSSL_PARAM_construct_end();
 600                 current_abstract = abstract;
 601             }
 602             break;
 603         }
 604
 605         /* Calling the encoder implementation */
 606
 607         if (ok) {
 608             OSSL_CORE_BIO *cbio = NULL;
 609             BIO *current_out = NULL;
 610
 611             /*
 612              * If we're at the last encoder instance to use, we're setting up
 613              * final output.  Otherwise, set up an intermediary memory output.
 614              */
 615             if (top)
 616                 current_out = data->bio;
 617             else if ((current_out = allocated_out = BIO_new(BIO_s_mem()))
 618                      == NULL)
 619                 ok = 0;     /* Assume BIO_new() recorded an error */
 620
 621             if (ok)
 622                 ok = (cbio = ossl_core_bio_new_from_bio(current_out)) != NULL;
 623             if (ok) {
 624                 ok = current_encoder->encode(current_encoder_ctx, cbio,
 625                                              original_data, current_abstract,
 626                                              data->ctx->selection,
 627                                              ossl_pw_passphrase_callback_enc,
 628                                              &data->ctx->pwdata);
 629                 OSSL_TRACE_BEGIN(ENCODER) {
 630                     BIO_printf(trc_out,
 631                                "[%d] (ctx %p) Running encoder instance %p => %d\n",
 632                                data->level, (void *)data->ctx,
 633                                (void *)current_encoder_inst, ok);
 634                 } OSSL_TRACE_END(ENCODER);
 635             }
 636
 637             ossl_core_bio_free(cbio);
 638             data->prev_encoder_inst = current_encoder_inst;
 639         }
 640     }
 641
 642     /* Cleanup and collecting the result */
 643
 644     OPENSSL_free(data->running_output);
 645     data->running_output = NULL;
 646
 647     /*
 648      * Steal the output from the BIO_s_mem, if we did allocate one.
 649      * That'll be the data for an object abstraction in the next round.
 650      */
 651     if (allocated_out != NULL) {
 652         BUF_MEM *buf;
 653
 654         BIO_get_mem_ptr(allocated_out, &buf);
 655         data->running_output = (unsigned char *)buf->data;
 656         data->running_output_length = buf->length;
 657         memset(buf, 0, sizeof(*buf));
 658     }
 659
 660     BIO_free(allocated_out);
 661     if (original_data != NULL)
 662         data->ctx->cleanup(data->ctx->construct_data);
 663     return ok;
 664 }