1 /*
2 * Copyright 2016-2024 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 "internal/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
openssl_fopen(const char * filename,const char * mode)38 FILE *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;
43 DWORD flags;
44 #endif
45
46 if (filename == NULL)
47 return NULL;
48 #if defined(_WIN32) && defined(CP_UTF8)
49 len_0 = (int)strlen(filename) + 1;
50
51 /*
52 * Basically there are three cases to cover: a) filename is
53 * pure ASCII string; b) actual UTF-8 encoded string and
54 * c) locale-ized string, i.e. one containing 8-bit
55 * characters that are meaningful in current system locale.
56 * If filename is pure ASCII or real UTF-8 encoded string,
57 * MultiByteToWideChar succeeds and _wfopen works. If
58 * filename is locale-ized string, chances are that
59 * MultiByteToWideChar fails reporting
60 * ERROR_NO_UNICODE_TRANSLATION, in which case we fall
61 * back to fopen...
62 */
63 if ((sz = MultiByteToWideChar(CP_UTF8, (flags = MB_ERR_INVALID_CHARS),
64 filename, len_0, NULL, 0))
65 > 0
66 || (GetLastError() == ERROR_INVALID_FLAGS && (sz = MultiByteToWideChar(CP_UTF8, (flags = 0), filename, len_0, NULL, 0)) > 0)) {
67 WCHAR wmode[8];
68 WCHAR *wfilename = _alloca(sz * sizeof(WCHAR));
69
70 if (MultiByteToWideChar(CP_UTF8, flags,
71 filename, len_0, wfilename, sz)
72 && MultiByteToWideChar(CP_UTF8, 0, mode, strlen(mode) + 1,
73 wmode, OSSL_NELEM(wmode))
74 && (file = _wfopen(wfilename, wmode)) == NULL && (errno == ENOENT || errno == EBADF)) {
75 /*
76 * UTF-8 decode succeeded, but no file, filename
77 * could still have been locale-ized...
78 */
79 file = fopen(filename, mode);
80 }
81 } else if (GetLastError() == ERROR_NO_UNICODE_TRANSLATION) {
82 file = fopen(filename, mode);
83 }
84 #elif defined(__DJGPP__)
85 {
86 char *newname = NULL;
87
88 if (pathconf(filename, _PC_NAME_MAX) <= 12) { /* 8.3 file system? */
89 char *iterator;
90 char lastchar;
91
92 if ((newname = OPENSSL_malloc(strlen(filename) + 1)) == NULL)
93 return NULL;
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
openssl_fopen(const char * filename,const char * mode)121 void *openssl_fopen(const char *filename, const char *mode)
122 {
123 return NULL;
124 }
125
126 #endif
127