providers/implementations/storemgmt/file_store.c

   1 /*
   2  * Copyright 2020-2022 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 /* This file has quite some overlap with engines/e_loader_attic.c */
  11
  12 #include <string.h>
  13 #include <sys/stat.h>
  14 #include <ctype.h>  /* isdigit */
  15 #include <assert.h>
  16
  17 #include <openssl/core_dispatch.h>
  18 #include <openssl/core_names.h>
  19 #include <openssl/core_object.h>
  20 #include <openssl/bio.h>
  21 #include <openssl/err.h>
  22 #include <openssl/params.h>
  23 #include <openssl/decoder.h>
  24 #include <openssl/proverr.h>
  25 #include <openssl/store.h>       /* The OSSL_STORE_INFO type numbers */
  26 #include "internal/cryptlib.h"
  27 #include "internal/o_dir.h"
  28 #include "crypto/decoder.h"
  29 #include "crypto/ctype.h"        /* ossl_isdigit() */
  30 #include "prov/implementations.h"
  31 #include "prov/bio.h"
  32 #include "file_store_local.h"
  33
  34 DEFINE_STACK_OF(OSSL_STORE_INFO)
  35
  36 #ifdef _WIN32
  37 # define stat _stat
  38 #endif
  39
  40 #ifndef S_ISDIR
  41 # define S_ISDIR(a) (((a) & S_IFMT) == S_IFDIR)
  42 #endif
  43
  44 static OSSL_FUNC_store_open_fn file_open;
  45 static OSSL_FUNC_store_attach_fn file_attach;
  46 static OSSL_FUNC_store_settable_ctx_params_fn file_settable_ctx_params;
  47 static OSSL_FUNC_store_set_ctx_params_fn file_set_ctx_params;
  48 static OSSL_FUNC_store_load_fn file_load;
  49 static OSSL_FUNC_store_eof_fn file_eof;
  50 static OSSL_FUNC_store_close_fn file_close;
  51
  52 /*
  53  * This implementation makes full use of OSSL_DECODER, and then some.
  54  * It uses its own internal decoder implementation that reads DER and
  55  * passes that on to the data callback; this decoder is created with
  56  * internal OpenSSL functions, thereby bypassing the need for a surrounding
  57  * provider.  This is ok, since this is a local decoder, not meant for
  58  * public consumption.  It also uses the libcrypto internal decoder
  59  * setup function ossl_decoder_ctx_setup_for_pkey(), to allow the
  60  * last resort decoder to be added first (and thereby be executed last).
  61  * Finally, it sets up its own construct and cleanup functions.
  62  *
  63  * Essentially, that makes this implementation a kind of glorified decoder.
  64  */
  65
  66 struct file_ctx_st {
  67     void *provctx;
  68     char *uri;                   /* The URI we currently try to load */
  69     enum {
  70         IS_FILE = 0,             /* Read file and pass results */
  71         IS_DIR                   /* Pass directory entry names */
  72     } type;
  73
  74     union {
  75         /* Used with |IS_FILE| */
  76         struct {
  77             BIO *file;
  78
  79             OSSL_DECODER_CTX *decoderctx;
  80             char *input_type;
  81             char *propq;    /* The properties we got as a parameter */
  82         } file;
  83
  84         /* Used with |IS_DIR| */
  85         struct {
  86             OPENSSL_DIR_CTX *ctx;
  87             int end_reached;
  88
  89             /*
  90              * When a search expression is given, these are filled in.
  91              * |search_name| contains the file basename to look for.
  92              * The string is exactly 8 characters long.
  93              */
  94             char search_name[9];
  95
  96             /*
  97              * The directory reading utility we have combines opening with
  98              * reading the first name.  To make sure we can detect the end
  99              * at the right time, we read early and cache the name.
 100              */
 101             const char *last_entry;
 102             int last_errno;
 103         } dir;
 104     } _;
 105
 106     /* Expected object type.  May be unspecified */
 107     int expected_type;
 108 };
 109
 110 static void free_file_ctx(struct file_ctx_st *ctx)
 111 {
 112     if (ctx == NULL)
 113         return;
 114
 115     OPENSSL_free(ctx->uri);
 116     if (ctx->type != IS_DIR) {
 117         OSSL_DECODER_CTX_free(ctx->_.file.decoderctx);
 118         OPENSSL_free(ctx->_.file.propq);
 119         OPENSSL_free(ctx->_.file.input_type);
 120     }
 121     OPENSSL_free(ctx);
 122 }
 123
 124 static struct file_ctx_st *new_file_ctx(int type, const char *uri,
 125                                         void *provctx)
 126 {
 127     struct file_ctx_st *ctx = NULL;
 128
 129     if ((ctx = OPENSSL_zalloc(sizeof(*ctx))) != NULL
 130         && (uri == NULL || (ctx->uri = OPENSSL_strdup(uri)) != NULL)) {
 131         ctx->type = type;
 132         ctx->provctx = provctx;
 133         return ctx;
 134     }
 135     free_file_ctx(ctx);
 136     return NULL;
 137 }
 138
 139 static OSSL_DECODER_CONSTRUCT file_load_construct;
 140 static OSSL_DECODER_CLEANUP file_load_cleanup;
 141
 142 /*-
 143  *  Opening / attaching streams and directories
 144  *  -------------------------------------------
 145  */
 146
 147 /*
 148  * Function to service both file_open() and file_attach()
 149  *
 150  *
 151  */
 152 static struct file_ctx_st *file_open_stream(BIO *source, const char *uri,
 153                                             void *provctx)
 154 {
 155     struct file_ctx_st *ctx;
 156
 157     if ((ctx = new_file_ctx(IS_FILE, uri, provctx)) == NULL) {
 158         ERR_raise(ERR_LIB_PROV, ERR_R_PROV_LIB);
 159         goto err;
 160     }
 161
 162     ctx->_.file.file = source;
 163
 164     return ctx;
 165  err:
 166     free_file_ctx(ctx);
 167     return NULL;
 168 }
 169
 170 static void *file_open_dir(const char *path, const char *uri, void *provctx)
 171 {
 172     struct file_ctx_st *ctx;
 173
 174     if ((ctx = new_file_ctx(IS_DIR, uri, provctx)) == NULL) {
 175         ERR_raise(ERR_LIB_PROV, ERR_R_PROV_LIB);
 176         return NULL;
 177     }
 178
 179     ctx->_.dir.last_entry = OPENSSL_DIR_read(&ctx->_.dir.ctx, path);
 180     ctx->_.dir.last_errno = errno;
 181     if (ctx->_.dir.last_entry == NULL) {
 182         if (ctx->_.dir.last_errno != 0) {
 183             ERR_raise_data(ERR_LIB_SYS, ctx->_.dir.last_errno,
 184                            "Calling OPENSSL_DIR_read(\"%s\")", path);
 185             goto err;
 186         }
 187         ctx->_.dir.end_reached = 1;
 188     }
 189     return ctx;
 190  err:
 191     file_close(ctx);
 192     return NULL;
 193 }
 194
 195 static void *file_open(void *provctx, const char *uri)
 196 {
 197     struct file_ctx_st *ctx = NULL;
 198     struct stat st;
 199     struct {
 200         const char *path;
 201         unsigned int check_absolute:1;
 202     } path_data[2];
 203     size_t path_data_n = 0, i;
 204     const char *path, *p = uri, *q;
 205     BIO *bio;
 206
 207     ERR_set_mark();
 208
 209     /*
 210      * First step, just take the URI as is.
 211      */
 212     path_data[path_data_n].check_absolute = 0;
 213     path_data[path_data_n++].path = uri;
 214
 215     /*
 216      * Second step, if the URI appears to start with the "file" scheme,
 217      * extract the path and make that the second path to check.
 218      * There's a special case if the URI also contains an authority, then
 219      * the full URI shouldn't be used as a path anywhere.
 220      */
 221     if (CHECK_AND_SKIP_CASE_PREFIX(p, "file:")) {
 222         q = p;
 223         if (CHECK_AND_SKIP_CASE_PREFIX(q, "//")) {
 224             path_data_n--;           /* Invalidate using the full URI */
 225             if (CHECK_AND_SKIP_CASE_PREFIX(q, "localhost/")
 226                     || CHECK_AND_SKIP_CASE_PREFIX(q, "/")) {
 227                 p = q - 1;
 228             } else {
 229                 ERR_clear_last_mark();
 230                 ERR_raise(ERR_LIB_PROV, PROV_R_URI_AUTHORITY_UNSUPPORTED);
 231                 return NULL;
 232             }
 233         }
 234
 235         path_data[path_data_n].check_absolute = 1;
 236 #ifdef _WIN32
 237         /* Windows "file:" URIs with a drive letter start with a '/' */
 238         if (p[0] == '/' && p[2] == ':' && p[3] == '/') {
 239             char c = tolower(p[1]);
 240
 241             if (c >= 'a' && c <= 'z') {
 242                 p++;
 243                 /* We know it's absolute, so no need to check */
 244                 path_data[path_data_n].check_absolute = 0;
 245             }
 246         }
 247 #endif
 248         path_data[path_data_n++].path = p;
 249     }
 250
 251
 252     for (i = 0, path = NULL; path == NULL && i < path_data_n; i++) {
 253         /*
 254          * If the scheme "file" was an explicit part of the URI, the path must
 255          * be absolute.  So says RFC 8089
 256          */
 257         if (path_data[i].check_absolute && path_data[i].path[0] != '/') {
 258             ERR_clear_last_mark();
 259             ERR_raise_data(ERR_LIB_PROV, PROV_R_PATH_MUST_BE_ABSOLUTE,
 260                            "Given path=%s", path_data[i].path);
 261             return NULL;
 262         }
 263
 264         if (stat(path_data[i].path, &st) < 0) {
 265             ERR_raise_data(ERR_LIB_SYS, errno,
 266                            "calling stat(%s)",
 267                            path_data[i].path);
 268         } else {
 269             path = path_data[i].path;
 270         }
 271     }
 272     if (path == NULL) {
 273         ERR_clear_last_mark();
 274         return NULL;
 275     }
 276
 277     /* Successfully found a working path, clear possible collected errors */
 278     ERR_pop_to_mark();
 279
 280     if (S_ISDIR(st.st_mode))
 281         ctx = file_open_dir(path, uri, provctx);
 282     else if ((bio = BIO_new_file(path, "rb")) == NULL
 283              || (ctx = file_open_stream(bio, uri, provctx)) == NULL)
 284         BIO_free_all(bio);
 285
 286     return ctx;
 287 }
 288
 289 void *file_attach(void *provctx, OSSL_CORE_BIO *cin)
 290 {
 291     struct file_ctx_st *ctx;
 292     BIO *new_bio = ossl_bio_new_from_core_bio(provctx, cin);
 293
 294     if (new_bio == NULL)
 295         return NULL;
 296
 297     ctx = file_open_stream(new_bio, NULL, provctx);
 298     if (ctx == NULL)
 299         BIO_free(new_bio);
 300     return ctx;
 301 }
 302
 303 /*-
 304  *  Setting parameters
 305  *  ------------------
 306  */
 307
 308 static const OSSL_PARAM *file_settable_ctx_params(void *provctx)
 309 {
 310     static const OSSL_PARAM known_settable_ctx_params[] = {
 311         OSSL_PARAM_utf8_string(OSSL_STORE_PARAM_PROPERTIES, NULL, 0),
 312         OSSL_PARAM_int(OSSL_STORE_PARAM_EXPECT, NULL),
 313         OSSL_PARAM_octet_string(OSSL_STORE_PARAM_SUBJECT, NULL, 0),
 314         OSSL_PARAM_utf8_string(OSSL_STORE_PARAM_INPUT_TYPE, NULL, 0),
 315         OSSL_PARAM_END
 316     };
 317     return known_settable_ctx_params;
 318 }
 319
 320 static int file_set_ctx_params(void *loaderctx, const OSSL_PARAM params[])
 321 {
 322     struct file_ctx_st *ctx = loaderctx;
 323     const OSSL_PARAM *p;
 324
 325     if (params == NULL)
 326         return 1;
 327
 328     if (ctx->type != IS_DIR) {
 329         /* these parameters are ignored for directories */
 330         p = OSSL_PARAM_locate_const(params, OSSL_STORE_PARAM_PROPERTIES);
 331         if (p != NULL) {
 332             OPENSSL_free(ctx->_.file.propq);
 333             ctx->_.file.propq = NULL;
 334             if (!OSSL_PARAM_get_utf8_string(p, &ctx->_.file.propq, 0))
 335                 return 0;
 336         }
 337         p = OSSL_PARAM_locate_const(params, OSSL_STORE_PARAM_INPUT_TYPE);
 338         if (p != NULL) {
 339             OPENSSL_free(ctx->_.file.input_type);
 340             ctx->_.file.input_type = NULL;
 341             if (!OSSL_PARAM_get_utf8_string(p, &ctx->_.file.input_type, 0))
 342                 return 0;
 343         }
 344     }
 345     p = OSSL_PARAM_locate_const(params, OSSL_STORE_PARAM_EXPECT);
 346     if (p != NULL && !OSSL_PARAM_get_int(p, &ctx->expected_type))
 347         return 0;
 348     p = OSSL_PARAM_locate_const(params, OSSL_STORE_PARAM_SUBJECT);
 349     if (p != NULL) {
 350         const unsigned char *der = NULL;
 351         size_t der_len = 0;
 352         X509_NAME *x509_name;
 353         unsigned long hash;
 354         int ok;
 355
 356         if (ctx->type != IS_DIR) {
 357             ERR_raise(ERR_LIB_PROV,
 358                       PROV_R_SEARCH_ONLY_SUPPORTED_FOR_DIRECTORIES);
 359             return 0;
 360         }
 361
 362         if (!OSSL_PARAM_get_octet_string_ptr(p, (const void **)&der, &der_len)
 363             || (x509_name = d2i_X509_NAME(NULL, &der, der_len)) == NULL)
 364             return 0;
 365         hash = X509_NAME_hash_ex(x509_name,
 366                                  ossl_prov_ctx_get0_libctx(ctx->provctx), NULL,
 367                                  &ok);
 368         BIO_snprintf(ctx->_.dir.search_name, sizeof(ctx->_.dir.search_name),
 369                      "%08lx", hash);
 370         X509_NAME_free(x509_name);
 371         if (ok == 0)
 372             return 0;
 373     }
 374     return 1;
 375 }
 376
 377 /*-
 378  *  Loading an object from a stream
 379  *  -------------------------------
 380  */
 381
 382 struct file_load_data_st {
 383     OSSL_CALLBACK *object_cb;
 384     void *object_cbarg;
 385 };
 386
 387 static int file_load_construct(OSSL_DECODER_INSTANCE *decoder_inst,
 388                                const OSSL_PARAM *params, void *construct_data)
 389 {
 390     struct file_load_data_st *data = construct_data;
 391
 392     /*
 393      * At some point, we may find it justifiable to recognise PKCS#12 and
 394      * handle it specially here, making |file_load()| return pass its
 395      * contents one piece at ta time, like |e_loader_attic.c| does.
 396      *
 397      * However, that currently means parsing them out, which converts the
 398      * DER encoded PKCS#12 into a bunch of EVP_PKEYs and X509s, just to
 399      * have to re-encode them into DER to create an object abstraction for
 400      * each of them.
 401      * It's much simpler (less churn) to pass on the object abstraction we
 402      * get to the load_result callback and leave it to that one to do the
 403      * work.  If that's libcrypto code, we know that it has much better
 404      * possibilities to handle the EVP_PKEYs and X509s without the extra
 405      * churn.
 406      */
 407
 408     return data->object_cb(params, data->object_cbarg);
 409 }
 410
 411 void file_load_cleanup(void *construct_data)
 412 {
 413     /* Nothing to do */
 414 }
 415
 416 static int file_setup_decoders(struct file_ctx_st *ctx)
 417 {
 418     OSSL_LIB_CTX *libctx = ossl_prov_ctx_get0_libctx(ctx->provctx);
 419     const OSSL_ALGORITHM *to_algo = NULL;
 420     int ok = 0;
 421
 422     /* Setup for this session, so only if not already done */
 423     if (ctx->_.file.decoderctx == NULL) {
 424         if ((ctx->_.file.decoderctx = OSSL_DECODER_CTX_new()) == NULL) {
 425             ERR_raise(ERR_LIB_PROV, ERR_R_OSSL_DECODER_LIB);
 426             goto err;
 427         }
 428
 429         /* Make sure the input type is set */
 430         if (!OSSL_DECODER_CTX_set_input_type(ctx->_.file.decoderctx,
 431                                              ctx->_.file.input_type)) {
 432             ERR_raise(ERR_LIB_PROV, ERR_R_OSSL_DECODER_LIB);
 433             goto err;
 434         }
 435
 436         /*
 437          * Where applicable, set the outermost structure name.
 438          * The goal is to avoid the STORE object types that are
 439          * potentially password protected but aren't interesting
 440          * for this load.
 441          */
 442         switch (ctx->expected_type) {
 443         case OSSL_STORE_INFO_CERT:
 444             if (!OSSL_DECODER_CTX_set_input_structure(ctx->_.file.decoderctx,
 445                                                       "Certificate")) {
 446                 ERR_raise(ERR_LIB_PROV, ERR_R_OSSL_DECODER_LIB);
 447                 goto err;
 448             }
 449             break;
 450         case OSSL_STORE_INFO_CRL:
 451             if (!OSSL_DECODER_CTX_set_input_structure(ctx->_.file.decoderctx,
 452                                                       "CertificateList")) {
 453                 ERR_raise(ERR_LIB_PROV, ERR_R_OSSL_DECODER_LIB);
 454                 goto err;
 455             }
 456             break;
 457         default:
 458             break;
 459         }
 460
 461         for (to_algo = ossl_any_to_obj_algorithm;
 462              to_algo->algorithm_names != NULL;
 463              to_algo++) {
 464             OSSL_DECODER *to_obj = NULL;
 465             OSSL_DECODER_INSTANCE *to_obj_inst = NULL;
 466
 467             /*
 468              * Create the internal last resort decoder implementation
 469              * together with a "decoder instance".
 470              * The decoder doesn't need any identification or to be
 471              * attached to any provider, since it's only used locally.
 472              */
 473             to_obj = ossl_decoder_from_algorithm(0, to_algo, NULL);
 474             if (to_obj != NULL)
 475                 to_obj_inst = ossl_decoder_instance_new(to_obj, ctx->provctx);
 476             OSSL_DECODER_free(to_obj);
 477             if (to_obj_inst == NULL)
 478                 goto err;
 479
 480             if (!ossl_decoder_ctx_add_decoder_inst(ctx->_.file.decoderctx,
 481                                                    to_obj_inst)) {
 482                 ossl_decoder_instance_free(to_obj_inst);
 483                 ERR_raise(ERR_LIB_PROV, ERR_R_OSSL_DECODER_LIB);
 484                 goto err;
 485             }
 486         }
 487         /* Add on the usual extra decoders */
 488         if (!OSSL_DECODER_CTX_add_extra(ctx->_.file.decoderctx,
 489                                         libctx, ctx->_.file.propq)) {
 490             ERR_raise(ERR_LIB_PROV, ERR_R_OSSL_DECODER_LIB);
 491             goto err;
 492         }
 493
 494         /*
 495          * Then install our constructor hooks, which just passes decoded
 496          * data to the load callback
 497          */
 498         if (!OSSL_DECODER_CTX_set_construct(ctx->_.file.decoderctx,
 499                                             file_load_construct)
 500             || !OSSL_DECODER_CTX_set_cleanup(ctx->_.file.decoderctx,
 501                                              file_load_cleanup)) {
 502             ERR_raise(ERR_LIB_PROV, ERR_R_OSSL_DECODER_LIB);
 503             goto err;
 504         }
 505     }
 506
 507     ok = 1;
 508  err:
 509     return ok;
 510 }
 511
 512 static int file_load_file(struct file_ctx_st *ctx,
 513                           OSSL_CALLBACK *object_cb, void *object_cbarg,
 514                           OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg)
 515 {
 516     struct file_load_data_st data;
 517     int ret, err;
 518
 519     /* Setup the decoders (one time shot per session */
 520
 521     if (!file_setup_decoders(ctx))
 522         return 0;
 523
 524     /* Setup for this object */
 525
 526     data.object_cb = object_cb;
 527     data.object_cbarg = object_cbarg;
 528     OSSL_DECODER_CTX_set_construct_data(ctx->_.file.decoderctx, &data);
 529     OSSL_DECODER_CTX_set_passphrase_cb(ctx->_.file.decoderctx, pw_cb, pw_cbarg);
 530
 531     /* Launch */
 532
 533     ERR_set_mark();
 534     ret = OSSL_DECODER_from_bio(ctx->_.file.decoderctx, ctx->_.file.file);
 535     if (BIO_eof(ctx->_.file.file)
 536         && ((err = ERR_peek_last_error()) != 0)
 537         && ERR_GET_LIB(err) == ERR_LIB_OSSL_DECODER
 538         && ERR_GET_REASON(err) == ERR_R_UNSUPPORTED)
 539         ERR_pop_to_mark();
 540     else
 541         ERR_clear_last_mark();
 542     return ret;
 543 }
 544
 545 /*-
 546  *  Loading a name object from a directory
 547  *  --------------------------------------
 548  */
 549
 550 static char *file_name_to_uri(struct file_ctx_st *ctx, const char *name)
 551 {
 552     char *data = NULL;
 553
 554     assert(name != NULL);
 555     {
 556         const char *pathsep = ossl_ends_with_dirsep(ctx->uri) ? "" : "/";
 557         long calculated_length = strlen(ctx->uri) + strlen(pathsep)
 558             + strlen(name) + 1 /* \0 */;
 559
 560         data = OPENSSL_zalloc(calculated_length);
 561         if (data == NULL)
 562             return NULL;
 563
 564         OPENSSL_strlcat(data, ctx->uri, calculated_length);
 565         OPENSSL_strlcat(data, pathsep, calculated_length);
 566         OPENSSL_strlcat(data, name, calculated_length);
 567     }
 568     return data;
 569 }
 570
 571 static int file_name_check(struct file_ctx_st *ctx, const char *name)
 572 {
 573     const char *p = NULL;
 574     size_t len = strlen(ctx->_.dir.search_name);
 575
 576     /* If there are no search criteria, all names are accepted */
 577     if (ctx->_.dir.search_name[0] == '\0')
 578         return 1;
 579
 580     /* If the expected type isn't supported, no name is accepted */
 581     if (ctx->expected_type != 0
 582         && ctx->expected_type != OSSL_STORE_INFO_CERT
 583         && ctx->expected_type != OSSL_STORE_INFO_CRL)
 584         return 0;
 585
 586     /*
 587      * First, check the basename
 588      */
 589     if (OPENSSL_strncasecmp(name, ctx->_.dir.search_name, len) != 0
 590         || name[len] != '.')
 591         return 0;
 592     p = &name[len + 1];
 593
 594     /*
 595      * Then, if the expected type is a CRL, check that the extension starts
 596      * with 'r'
 597      */
 598     if (*p == 'r') {
 599         p++;
 600         if (ctx->expected_type != 0
 601             && ctx->expected_type != OSSL_STORE_INFO_CRL)
 602             return 0;
 603     } else if (ctx->expected_type == OSSL_STORE_INFO_CRL) {
 604         return 0;
 605     }
 606
 607     /*
 608      * Last, check that the rest of the extension is a decimal number, at
 609      * least one digit long.
 610      */
 611     if (!isdigit(*p))
 612         return 0;
 613     while (isdigit(*p))
 614         p++;
 615
 616 #ifdef __VMS
 617     /*
 618      * One extra step here, check for a possible generation number.
 619      */
 620     if (*p == ';')
 621         for (p++; *p != '\0'; p++)
 622             if (!ossl_isdigit(*p))
 623                 break;
 624 #endif
 625
 626     /*
 627      * If we've reached the end of the string at this point, we've successfully
 628      * found a fitting file name.
 629      */
 630     return *p == '\0';
 631 }
 632
 633 static int file_load_dir_entry(struct file_ctx_st *ctx,
 634                                OSSL_CALLBACK *object_cb, void *object_cbarg,
 635                                OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg)
 636 {
 637     /* Prepare as much as possible in advance */
 638     static const int object_type = OSSL_OBJECT_NAME;
 639     OSSL_PARAM object[] = {
 640         OSSL_PARAM_int(OSSL_OBJECT_PARAM_TYPE, (int *)&object_type),
 641         OSSL_PARAM_utf8_string(OSSL_OBJECT_PARAM_DATA, NULL, 0),
 642         OSSL_PARAM_END
 643     };
 644     char *newname = NULL;
 645     int ok;
 646
 647     /* Loop until we get an error or until we have a suitable name */
 648     do {
 649         if (ctx->_.dir.last_entry == NULL) {
 650             if (!ctx->_.dir.end_reached) {
 651                 assert(ctx->_.dir.last_errno != 0);
 652                 ERR_raise(ERR_LIB_SYS, ctx->_.dir.last_errno);
 653             }
 654             /* file_eof() will tell if EOF was reached */
 655             return 0;
 656         }
 657
 658         /* flag acceptable names */
 659         if (ctx->_.dir.last_entry[0] != '.'
 660             && file_name_check(ctx, ctx->_.dir.last_entry)) {
 661
 662             /* If we can't allocate the new name, we fail */
 663             if ((newname =
 664                  file_name_to_uri(ctx, ctx->_.dir.last_entry)) == NULL)
 665                 return 0;
 666         }
 667
 668         /*
 669          * On the first call (with a NULL context), OPENSSL_DIR_read()
 670          * cares about the second argument.  On the following calls, it
 671          * only cares that it isn't NULL.  Therefore, we can safely give
 672          * it our URI here.
 673          */
 674         ctx->_.dir.last_entry = OPENSSL_DIR_read(&ctx->_.dir.ctx, ctx->uri);
 675         ctx->_.dir.last_errno = errno;
 676         if (ctx->_.dir.last_entry == NULL && ctx->_.dir.last_errno == 0)
 677             ctx->_.dir.end_reached = 1;
 678     } while (newname == NULL);
 679
 680     object[1].data = newname;
 681     object[1].data_size = strlen(newname);
 682     ok = object_cb(object, object_cbarg);
 683     OPENSSL_free(newname);
 684     return ok;
 685 }
 686
 687 /*-
 688  *  Loading, local dispatcher
 689  *  -------------------------
 690  */
 691
 692 static int file_load(void *loaderctx,
 693                      OSSL_CALLBACK *object_cb, void *object_cbarg,
 694                      OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg)
 695 {
 696     struct file_ctx_st *ctx = loaderctx;
 697
 698     switch (ctx->type) {
 699     case IS_FILE:
 700         return file_load_file(ctx, object_cb, object_cbarg, pw_cb, pw_cbarg);
 701     case IS_DIR:
 702         return
 703             file_load_dir_entry(ctx, object_cb, object_cbarg, pw_cb, pw_cbarg);
 704     default:
 705         break;
 706     }
 707
 708     /* ctx->type has an unexpected value */
 709     assert(0);
 710     return 0;
 711 }
 712
 713 /*-
 714  *  Eof detection and closing
 715  *  -------------------------
 716  */
 717
 718 static int file_eof(void *loaderctx)
 719 {
 720     struct file_ctx_st *ctx = loaderctx;
 721
 722     switch (ctx->type) {
 723     case IS_DIR:
 724         return ctx->_.dir.end_reached;
 725     case IS_FILE:
 726         /*
 727          * BIO_pending() checks any filter BIO.
 728          * BIO_eof() checks the source BIO.
 729          */
 730         return !BIO_pending(ctx->_.file.file)
 731             && BIO_eof(ctx->_.file.file);
 732     }
 733
 734     /* ctx->type has an unexpected value */
 735     assert(0);
 736     return 1;
 737 }
 738
 739 static int file_close_dir(struct file_ctx_st *ctx)
 740 {
 741     if (ctx->_.dir.ctx != NULL)
 742         OPENSSL_DIR_end(&ctx->_.dir.ctx);
 743     free_file_ctx(ctx);
 744     return 1;
 745 }
 746
 747 static int file_close_stream(struct file_ctx_st *ctx)
 748 {
 749     /*
 750      * This frees either the provider BIO filter (for file_attach()) OR
 751      * the allocated file BIO (for file_open()).
 752      */
 753     BIO_free(ctx->_.file.file);
 754     ctx->_.file.file = NULL;
 755
 756     free_file_ctx(ctx);
 757     return 1;
 758 }
 759
 760 static int file_close(void *loaderctx)
 761 {
 762     struct file_ctx_st *ctx = loaderctx;
 763
 764     switch (ctx->type) {
 765     case IS_DIR:
 766         return file_close_dir(ctx);
 767     case IS_FILE:
 768         return file_close_stream(ctx);
 769     }
 770
 771     /* ctx->type has an unexpected value */
 772     assert(0);
 773     return 1;
 774 }
 775
 776 const OSSL_DISPATCH ossl_file_store_functions[] = {
 777     { OSSL_FUNC_STORE_OPEN, (void (*)(void))file_open },
 778     { OSSL_FUNC_STORE_ATTACH, (void (*)(void))file_attach },
 779     { OSSL_FUNC_STORE_SETTABLE_CTX_PARAMS,
 780       (void (*)(void))file_settable_ctx_params },
 781     { OSSL_FUNC_STORE_SET_CTX_PARAMS, (void (*)(void))file_set_ctx_params },
 782     { OSSL_FUNC_STORE_LOAD, (void (*)(void))file_load },
 783     { OSSL_FUNC_STORE_EOF, (void (*)(void))file_eof },
 784     { OSSL_FUNC_STORE_CLOSE, (void (*)(void))file_close },
 785     OSSL_DISPATCH_END,
 786 };