1 /*
2 * Copyright (C) 2017 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the
13 * distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #ifndef _STDIO_H_
30 #error "Never include this file directly; instead, include <stdio.h>"
31 #endif
32
33 char* _Nullable __fgets_chk(char* _Nonnull, int, FILE* _Nonnull, size_t);
34 size_t __fread_chk(void* _Nonnull, size_t, size_t, FILE* _Nonnull, size_t) __INTRODUCED_IN(24);
35 size_t __fwrite_chk(const void* _Nonnull, size_t, size_t, FILE* _Nonnull, size_t) __INTRODUCED_IN(24);
36
37 #if defined(__BIONIC_FORTIFY) && !defined(__BIONIC_NO_STDIO_FORTIFY)
38
39 #if __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
40 /* No diag -- clang diagnoses misuses of this on its own. */
41 __BIONIC_FORTIFY_INLINE __printflike(3, 0)
vsnprintf(char * const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest,size_t size,const char * _Nonnull format,va_list ap)42 int vsnprintf(char* const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest, size_t size, const char* _Nonnull format, va_list ap)
43 __diagnose_as_builtin(__builtin_vsnprintf, 1, 2, 3, 4)
44 __overloadable {
45 return __builtin___vsnprintf_chk(dest, size, 0, __bos(dest), format, ap);
46 }
47
48 __BIONIC_FORTIFY_INLINE __printflike(2, 0)
vsprintf(char * const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest,const char * _Nonnull format,va_list ap)49 int vsprintf(char* const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest, const char* _Nonnull format, va_list ap) __overloadable {
50 return __builtin___vsprintf_chk(dest, 0, __bos(dest), format, ap);
51 }
52 #endif
53
54 __BIONIC_ERROR_FUNCTION_VISIBILITY
55 int sprintf(char* __BIONIC_COMPLICATED_NULLNESS dest, const char* _Nonnull format)
56 __overloadable
57 __enable_if(__bos_unevaluated_lt(__bos(dest), __builtin_strlen(format)),
58 "format string will always overflow destination buffer")
59 __errorattr("format string will always overflow destination buffer");
60
61 #if __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
62 __BIONIC_FORTIFY_VARIADIC __printflike(2, 3)
sprintf(char * const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest,const char * _Nonnull format,...)63 int sprintf(char* const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest, const char* _Nonnull format, ...) __overloadable {
64 va_list va;
65 va_start(va, format);
66 int result = __builtin___vsprintf_chk(dest, 0, __bos(dest), format, va);
67 va_end(va);
68 return result;
69 }
70
71 /* No diag -- clang diagnoses misuses of this on its own. */
72 __BIONIC_FORTIFY_VARIADIC __printflike(3, 4)
snprintf(char * const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest,size_t size,const char * _Nonnull format,...)73 int snprintf(char* const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest, size_t size, const char* _Nonnull format, ...)
74 __diagnose_as_builtin(__builtin_snprintf, 1, 2, 3)
75 __overloadable {
76 va_list va;
77 va_start(va, format);
78 int result = __builtin___vsnprintf_chk(dest, size, 0, __bos(dest), format, va);
79 va_end(va);
80 return result;
81 }
82 #endif
83
84 #define __bos_trivially_ge_mul(bos_val, size, count) \
85 __bos_dynamic_check_impl_and(bos_val, >=, (size) * (count), \
86 !__unsafe_check_mul_overflow(size, count))
87
88 __BIONIC_FORTIFY_INLINE
fread(void * const _Nonnull __pass_object_size0 buf,size_t size,size_t count,FILE * _Nonnull stream)89 size_t fread(void* const _Nonnull __pass_object_size0 buf, size_t size, size_t count, FILE* _Nonnull stream)
90 __overloadable
91 __clang_error_if(__unsafe_check_mul_overflow(size, count),
92 "in call to 'fread', size * count overflows")
93 __clang_error_if(__bos_unevaluated_lt(__bos0(buf), size * count),
94 "in call to 'fread', size * count is too large for the given buffer") {
95 #if __ANDROID_API__ >= 24 && __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
96 size_t bos = __bos0(buf);
97
98 if (!__bos_trivially_ge_mul(bos, size, count)) {
99 return __fread_chk(buf, size, count, stream, bos);
100 }
101 #endif
102 return __call_bypassing_fortify(fread)(buf, size, count, stream);
103 }
104
105 __BIONIC_FORTIFY_INLINE
fwrite(const void * const _Nonnull __pass_object_size0 buf,size_t size,size_t count,FILE * _Nonnull stream)106 size_t fwrite(const void* const _Nonnull __pass_object_size0 buf, size_t size, size_t count, FILE* _Nonnull stream)
107 __overloadable
108 __clang_error_if(__unsafe_check_mul_overflow(size, count),
109 "in call to 'fwrite', size * count overflows")
110 __clang_error_if(__bos_unevaluated_lt(__bos0(buf), size * count),
111 "in call to 'fwrite', size * count is too large for the given buffer") {
112 #if __ANDROID_API__ >= 24 && __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
113 size_t bos = __bos0(buf);
114
115 if (!__bos_trivially_ge_mul(bos, size, count)) {
116 return __fwrite_chk(buf, size, count, stream, bos);
117 }
118 #endif
119 return __call_bypassing_fortify(fwrite)(buf, size, count, stream);
120 }
121 #undef __bos_trivially_ge_mul
122
123 __BIONIC_FORTIFY_INLINE
fgets(char * const _Nonnull __pass_object_size dest,int size,FILE * _Nonnull stream)124 char* _Nullable fgets(char* const _Nonnull __pass_object_size dest, int size, FILE* _Nonnull stream)
125 __overloadable
126 __clang_error_if(size < 0, "in call to 'fgets', size should not be negative")
127 __clang_error_if(__bos_unevaluated_lt(__bos(dest), size),
128 "in call to 'fgets', size is larger than the destination buffer") {
129 #if __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
130 size_t bos = __bos(dest);
131
132 if (!__bos_dynamic_check_impl_and(bos, >=, (size_t)size, size >= 0)) {
133 return __fgets_chk(dest, size, stream, bos);
134 }
135 #endif
136 return __call_bypassing_fortify(fgets)(dest, size, stream);
137 }
138
139 #endif /* defined(__BIONIC_FORTIFY) */
140