1/*
2 * Copyright 2016-2018 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 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 "e_os.h"
29#include "internal/cryptlib.h"
30
31#if !defined(OPENSSL_NO_STDIO)
32
33# include <stdio.h>
34# ifdef __DJGPP__
35# include <unistd.h>
36# endif
37
38FILE *openssl_fopen(const char *filename, const char *mode)
39{
40 FILE *file = NULL;
41# if defined(_WIN32) && defined(CP_UTF8)
42 int sz, len_0 = (int)strlen(filename) + 1;
43 DWORD flags;
44
45 /*
46 * Basically there are three cases to cover: a) filename is
47 * pure ASCII string; b) actual UTF-8 encoded string and
48 * c) locale-ized string, i.e. one containing 8-bit
49 * characters that are meaningful in current system locale.
50 * If filename is pure ASCII or real UTF-8 encoded string,
51 * MultiByteToWideChar succeeds and _wfopen works. If
52 * filename is locale-ized string, chances are that
53 * MultiByteToWideChar fails reporting
54 * ERROR_NO_UNICODE_TRANSLATION, in which case we fall
55 * back to fopen...
56 */
57 if ((sz = MultiByteToWideChar(CP_UTF8, (flags = MB_ERR_INVALID_CHARS),
58 filename, len_0, NULL, 0)) > 0 ||
59 (GetLastError() == ERROR_INVALID_FLAGS &&
60 (sz = MultiByteToWideChar(CP_UTF8, (flags = 0),
61 filename, len_0, NULL, 0)) > 0)
62 ) {
63 WCHAR wmode[8];
64 WCHAR *wfilename = _alloca(sz * sizeof(WCHAR));
65
66 if (MultiByteToWideChar(CP_UTF8, flags,
67 filename, len_0, wfilename, sz) &&
68 MultiByteToWideChar(CP_UTF8, 0, mode, strlen(mode) + 1,
69 wmode, OSSL_NELEM(wmode)) &&
70 (file = _wfopen(wfilename, wmode)) == NULL &&
71 (errno == ENOENT || errno == EBADF)
72 ) {
73 /*
74 * UTF-8 decode succeeded, but no file, filename
75 * could still have been locale-ized...
76 */
77 file = fopen(filename, mode);
78 }
79 } else if (GetLastError() == ERROR_NO_UNICODE_TRANSLATION) {
80 file = fopen(filename, mode);
81 }
82# elif defined(__DJGPP__)
83 {
84 char *newname = NULL;
85
86 if (pathconf(filename, _PC_NAME_MAX) <= 12) { /* 8.3 file system? */
87 char *iterator;
88 char lastchar;
89
90 if ((newname = OPENSSL_malloc(strlen(filename) + 1)) == NULL) {
91 CRYPTOerr(CRYPTO_F_OPENSSL_FOPEN, ERR_R_MALLOC_FAILURE);
92 return NULL;
93 }
94
95 for (iterator = newname, lastchar = '\0';
96 *filename; filename++, iterator++) {
97 if (lastchar == '/' && filename[0] == '.'
98 && filename[1] != '.' && filename[1] != '/') {
99 /* Leading dots are not permitted in plain DOS. */
100 *iterator = '_';
101 } else {
102 *iterator = *filename;
103 }
104 lastchar = *filename;
105 }
106 *iterator = '\0';
107 filename = newname;
108 }
109 file = fopen(filename, mode);
110
111 OPENSSL_free(newname);
112 }
113# else
114 file = fopen(filename, mode);
115# endif
116 return file;
117}
118
119#else
120
121void *openssl_fopen(const char *filename, const char *mode)
122{
123 return NULL;
124}
125
126#endif
127