crypto/bio/bss_file.c

   1 /*
   2  * Copyright 1995-2021 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 #if defined(__linux) || defined(__sun) || defined(__hpux)
  11 /*
  12  * Following definition aliases fopen to fopen64 on above mentioned
  13  * platforms. This makes it possible to open and sequentially access files
  14  * larger than 2GB from 32-bit application. It does not allow one to traverse
  15  * them beyond 2GB with fseek/ftell, but on the other hand *no* 32-bit
  16  * platform permits that, not with fseek/ftell. Not to mention that breaking
  17  * 2GB limit for seeking would require surgery to *our* API. But sequential
  18  * access suffices for practical cases when you can run into large files,
  19  * such as fingerprinting, so we can let API alone. For reference, the list
  20  * of 32-bit platforms which allow for sequential access of large files
  21  * without extra "magic" comprise *BSD, Darwin, IRIX...
  22  */
  23 # ifndef _FILE_OFFSET_BITS
  24 #  define _FILE_OFFSET_BITS 64
  25 # endif
  26 #endif
  27
  28 #include <stdio.h>
  29 #include <errno.h>
  30 #include "bio_local.h"
  31 #include <openssl/err.h>
  32
  33 #if !defined(OPENSSL_NO_STDIO)
  34
  35 static int file_write(BIO *h, const char *buf, int num);
  36 static int file_read(BIO *h, char *buf, int size);
  37 static int file_puts(BIO *h, const char *str);
  38 static int file_gets(BIO *h, char *str, int size);
  39 static long file_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  40 static int file_new(BIO *h);
  41 static int file_free(BIO *data);
  42 static const BIO_METHOD methods_filep = {
  43     BIO_TYPE_FILE,
  44     "FILE pointer",
  45     bwrite_conv,
  46     file_write,
  47     bread_conv,
  48     file_read,
  49     file_puts,
  50     file_gets,
  51     file_ctrl,
  52     file_new,
  53     file_free,
  54     NULL,                      /* file_callback_ctrl */
  55 };
  56
  57 BIO *BIO_new_file(const char *filename, const char *mode)
  58 {
  59     BIO  *ret;
  60     FILE *file = openssl_fopen(filename, mode);
  61     int fp_flags = BIO_CLOSE;
  62
  63     if (strchr(mode, 'b') == NULL)
  64         fp_flags |= BIO_FP_TEXT;
  65
  66     if (file == NULL) {
  67         ERR_raise_data(ERR_LIB_SYS, get_last_sys_error(),
  68                        "calling fopen(%s, %s)",
  69                        filename, mode);
  70         if (errno == ENOENT
  71 #ifdef ENXIO
  72             || errno == ENXIO
  73 #endif
  74             )
  75             ERR_raise(ERR_LIB_BIO, BIO_R_NO_SUCH_FILE);
  76         else
  77             ERR_raise(ERR_LIB_BIO, ERR_R_SYS_LIB);
  78         return NULL;
  79     }
  80     if ((ret = BIO_new(BIO_s_file())) == NULL) {
  81         fclose(file);
  82         return NULL;
  83     }
  84
  85     /* we did fopen -> we disengage UPLINK */
  86     BIO_clear_flags(ret, BIO_FLAGS_UPLINK_INTERNAL);
  87     BIO_set_fp(ret, file, fp_flags);
  88     return ret;
  89 }
  90
  91 BIO *BIO_new_fp(FILE *stream, int close_flag)
  92 {
  93     BIO *ret;
  94
  95     if ((ret = BIO_new(BIO_s_file())) == NULL)
  96         return NULL;
  97
  98     /* redundant flag, left for documentation purposes */
  99     BIO_set_flags(ret, BIO_FLAGS_UPLINK_INTERNAL);
 100     BIO_set_fp(ret, stream, close_flag);
 101     return ret;
 102 }
 103
 104 const BIO_METHOD *BIO_s_file(void)
 105 {
 106     return &methods_filep;
 107 }
 108
 109 static int file_new(BIO *bi)
 110 {
 111     bi->init = 0;
 112     bi->num = 0;
 113     bi->ptr = NULL;
 114     bi->flags = BIO_FLAGS_UPLINK_INTERNAL; /* default to UPLINK */
 115     return 1;
 116 }
 117
 118 static int file_free(BIO *a)
 119 {
 120     if (a == NULL)
 121         return 0;
 122     if (a->shutdown) {
 123         if ((a->init) && (a->ptr != NULL)) {
 124             if (a->flags & BIO_FLAGS_UPLINK_INTERNAL)
 125                 UP_fclose(a->ptr);
 126             else
 127                 fclose(a->ptr);
 128             a->ptr = NULL;
 129             a->flags = BIO_FLAGS_UPLINK_INTERNAL;
 130         }
 131         a->init = 0;
 132     }
 133     return 1;
 134 }
 135
 136 static int file_read(BIO *b, char *out, int outl)
 137 {
 138     int ret = 0;
 139
 140     if (b->init && (out != NULL)) {
 141         if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)
 142             ret = UP_fread(out, 1, (int)outl, b->ptr);
 143         else
 144             ret = fread(out, 1, (int)outl, (FILE *)b->ptr);
 145         if (ret == 0
 146             && (b->flags & BIO_FLAGS_UPLINK_INTERNAL
 147                 ? UP_ferror((FILE *)b->ptr) : ferror((FILE *)b->ptr))) {
 148             ERR_raise_data(ERR_LIB_SYS, get_last_sys_error(),
 149                            "calling fread()");
 150             ERR_raise(ERR_LIB_BIO, ERR_R_SYS_LIB);
 151             ret = -1;
 152         }
 153     }
 154     return ret;
 155 }
 156
 157 static int file_write(BIO *b, const char *in, int inl)
 158 {
 159     int ret = 0;
 160
 161     if (b->init && (in != NULL)) {
 162         if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)
 163             ret = UP_fwrite(in, (int)inl, 1, b->ptr);
 164         else
 165             ret = fwrite(in, (int)inl, 1, (FILE *)b->ptr);
 166         if (ret)
 167             ret = inl;
 168         /* ret=fwrite(in,1,(int)inl,(FILE *)b->ptr); */
 169         /*
 170          * according to Tim Hudson <tjh@openssl.org>, the commented out
 171          * version above can cause 'inl' write calls under some stupid stdio
 172          * implementations (VMS)
 173          */
 174     }
 175     return ret;
 176 }
 177
 178 static long file_ctrl(BIO *b, int cmd, long num, void *ptr)
 179 {
 180     long ret = 1;
 181     FILE *fp = (FILE *)b->ptr;
 182     FILE **fpp;
 183     char p[4];
 184     int st;
 185
 186     switch (cmd) {
 187     case BIO_C_FILE_SEEK:
 188     case BIO_CTRL_RESET:
 189         if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)
 190             ret = (long)UP_fseek(b->ptr, num, 0);
 191         else
 192             ret = (long)fseek(fp, num, 0);
 193         break;
 194     case BIO_CTRL_EOF:
 195         if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)
 196             ret = (long)UP_feof(fp);
 197         else
 198             ret = (long)feof(fp);
 199         break;
 200     case BIO_C_FILE_TELL:
 201     case BIO_CTRL_INFO:
 202         if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)
 203             ret = UP_ftell(b->ptr);
 204         else
 205             ret = ftell(fp);
 206         break;
 207     case BIO_C_SET_FILE_PTR:
 208         file_free(b);
 209         b->shutdown = (int)num & BIO_CLOSE;
 210         b->ptr = ptr;
 211         b->init = 1;
 212 # if BIO_FLAGS_UPLINK_INTERNAL!=0
 213 #  if defined(__MINGW32__) && defined(__MSVCRT__) && !defined(_IOB_ENTRIES)
 214 #   define _IOB_ENTRIES 20
 215 #  endif
 216         /* Safety net to catch purely internal BIO_set_fp calls */
 217 #  if (defined(_MSC_VER) && _MSC_VER>=1900) || defined(__BORLANDC__)
 218         if (ptr == stdin || ptr == stdout || ptr == stderr)
 219             BIO_clear_flags(b, BIO_FLAGS_UPLINK_INTERNAL);
 220 #  elif defined(_IOB_ENTRIES)
 221         if ((size_t)ptr >= (size_t)stdin &&
 222             (size_t)ptr < (size_t)(stdin + _IOB_ENTRIES))
 223             BIO_clear_flags(b, BIO_FLAGS_UPLINK_INTERNAL);
 224 #  endif
 225 # endif
 226 # ifdef UP_fsetmod
 227         if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)
 228             UP_fsetmod(b->ptr, (char)((num & BIO_FP_TEXT) ? 't' : 'b'));
 229         else
 230 # endif
 231         {
 232 # if defined(OPENSSL_SYS_WINDOWS)
 233             int fd = _fileno((FILE *)ptr);
 234             if (num & BIO_FP_TEXT)
 235                 _setmode(fd, _O_TEXT);
 236             else
 237                 _setmode(fd, _O_BINARY);
 238             /*
 239              * Reports show that ftell() isn't trustable in text mode.
 240              * This has been confirmed as a bug in the Universal C RTL, see
 241              * https://developercommunity.visualstudio.com/content/problem/425878/fseek-ftell-fail-in-text-mode-for-unix-style-text.html
 242              * The suggested work-around from Microsoft engineering is to
 243              * turn off buffering until the bug is resolved.
 244              */
 245             if ((num & BIO_FP_TEXT) != 0)
 246                 setvbuf((FILE *)ptr, NULL, _IONBF, 0);
 247 # elif defined(OPENSSL_SYS_MSDOS)
 248             int fd = fileno((FILE *)ptr);
 249             /* Set correct text/binary mode */
 250             if (num & BIO_FP_TEXT)
 251                 _setmode(fd, _O_TEXT);
 252             /* Dangerous to set stdin/stdout to raw (unless redirected) */
 253             else {
 254                 if (fd == STDIN_FILENO || fd == STDOUT_FILENO) {
 255                     if (isatty(fd) <= 0)
 256                         _setmode(fd, _O_BINARY);
 257                 } else
 258                     _setmode(fd, _O_BINARY);
 259             }
 260 # elif defined(OPENSSL_SYS_WIN32_CYGWIN)
 261             int fd = fileno((FILE *)ptr);
 262             if (!(num & BIO_FP_TEXT))
 263                 setmode(fd, O_BINARY);
 264 # endif
 265         }
 266         break;
 267     case BIO_C_SET_FILENAME:
 268         file_free(b);
 269         b->shutdown = (int)num & BIO_CLOSE;
 270         if (num & BIO_FP_APPEND) {
 271             if (num & BIO_FP_READ)
 272                 OPENSSL_strlcpy(p, "a+", sizeof(p));
 273             else
 274                 OPENSSL_strlcpy(p, "a", sizeof(p));
 275         } else if ((num & BIO_FP_READ) && (num & BIO_FP_WRITE))
 276             OPENSSL_strlcpy(p, "r+", sizeof(p));
 277         else if (num & BIO_FP_WRITE)
 278             OPENSSL_strlcpy(p, "w", sizeof(p));
 279         else if (num & BIO_FP_READ)
 280             OPENSSL_strlcpy(p, "r", sizeof(p));
 281         else {
 282             ERR_raise(ERR_LIB_BIO, BIO_R_BAD_FOPEN_MODE);
 283             ret = 0;
 284             break;
 285         }
 286 # if defined(OPENSSL_SYS_MSDOS) || defined(OPENSSL_SYS_WINDOWS)
 287         if (!(num & BIO_FP_TEXT))
 288             OPENSSL_strlcat(p, "b", sizeof(p));
 289         else
 290             OPENSSL_strlcat(p, "t", sizeof(p));
 291 # elif defined(OPENSSL_SYS_WIN32_CYGWIN)
 292         if (!(num & BIO_FP_TEXT))
 293             OPENSSL_strlcat(p, "b", sizeof(p));
 294 # endif
 295         fp = openssl_fopen(ptr, p);
 296         if (fp == NULL) {
 297             ERR_raise_data(ERR_LIB_SYS, get_last_sys_error(),
 298                            "calling fopen(%s, %s)",
 299                            ptr, p);
 300             ERR_raise(ERR_LIB_BIO, ERR_R_SYS_LIB);
 301             ret = 0;
 302             break;
 303         }
 304         b->ptr = fp;
 305         b->init = 1;
 306         /* we did fopen -> we disengage UPLINK */
 307         BIO_clear_flags(b, BIO_FLAGS_UPLINK_INTERNAL);
 308         break;
 309     case BIO_C_GET_FILE_PTR:
 310         /* the ptr parameter is actually a FILE ** in this case. */
 311         if (ptr != NULL) {
 312             fpp = (FILE **)ptr;
 313             *fpp = (FILE *)b->ptr;
 314         }
 315         break;
 316     case BIO_CTRL_GET_CLOSE:
 317         ret = (long)b->shutdown;
 318         break;
 319     case BIO_CTRL_SET_CLOSE:
 320         b->shutdown = (int)num;
 321         break;
 322     case BIO_CTRL_FLUSH:
 323         st = b->flags & BIO_FLAGS_UPLINK_INTERNAL
 324                 ? UP_fflush(b->ptr) : fflush((FILE *)b->ptr);
 325         if (st == EOF) {
 326             ERR_raise_data(ERR_LIB_SYS, get_last_sys_error(),
 327                            "calling fflush()");
 328             ERR_raise(ERR_LIB_BIO, ERR_R_SYS_LIB);
 329             ret = 0;
 330         }
 331         break;
 332     case BIO_CTRL_DUP:
 333         ret = 1;
 334         break;
 335
 336     case BIO_CTRL_WPENDING:
 337     case BIO_CTRL_PENDING:
 338     case BIO_CTRL_PUSH:
 339     case BIO_CTRL_POP:
 340     default:
 341         ret = 0;
 342         break;
 343     }
 344     return ret;
 345 }
 346
 347 static int file_gets(BIO *bp, char *buf, int size)
 348 {
 349     int ret = 0;
 350
 351     buf[0] = '\0';
 352     if (bp->flags & BIO_FLAGS_UPLINK_INTERNAL) {
 353         if (!UP_fgets(buf, size, bp->ptr))
 354             goto err;
 355     } else {
 356         if (!fgets(buf, size, (FILE *)bp->ptr))
 357             goto err;
 358     }
 359     if (buf[0] != '\0')
 360         ret = strlen(buf);
 361  err:
 362     return ret;
 363 }
 364
 365 static int file_puts(BIO *bp, const char *str)
 366 {
 367     int n, ret;
 368
 369     n = strlen(str);
 370     ret = file_write(bp, str, n);
 371     return ret;
 372 }
 373
 374 #else
 375
 376 static int file_write(BIO *b, const char *in, int inl)
 377 {
 378     return -1;
 379 }
 380 static int file_read(BIO *b, char *out, int outl)
 381 {
 382     return -1;
 383 }
 384 static int file_puts(BIO *bp, const char *str)
 385 {
 386     return -1;
 387 }
 388 static int file_gets(BIO *bp, char *buf, int size)
 389 {
 390     return 0;
 391 }
 392 static long file_ctrl(BIO *b, int cmd, long num, void *ptr)
 393 {
 394     return 0;
 395 }
 396 static int file_new(BIO *bi)
 397 {
 398     return 0;
 399 }
 400 static int file_free(BIO *a)
 401 {
 402     return 0;
 403 }
 404
 405 static const BIO_METHOD methods_filep = {
 406     BIO_TYPE_FILE,
 407     "FILE pointer",
 408     bwrite_conv,
 409     file_write,
 410     bread_conv,
 411     file_read,
 412     file_puts,
 413     file_gets,
 414     file_ctrl,
 415     file_new,
 416     file_free,
 417     NULL,                      /* file_callback_ctrl */
 418 };
 419
 420 const BIO_METHOD *BIO_s_file(void)
 421 {
 422     return &methods_filep;
 423 }
 424
 425 BIO *BIO_new_file(const char *filename, const char *mode)
 426 {
 427     return NULL;
 428 }
 429
 430 #endif                         /* OPENSSL_NO_STDIO */