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
35 #if __BIONIC_AVAILABILITY_GUARD(24)
36 size_t __fread_chk(void* _Nonnull, size_t, size_t, FILE* _Nonnull, size_t) __INTRODUCED_IN(24);
37 size_t __fwrite_chk(const void* _Nonnull, size_t, size_t, FILE* _Nonnull, size_t) __INTRODUCED_IN(24);
38 #endif /* __BIONIC_AVAILABILITY_GUARD(24) */
39
40
41 #if defined(__BIONIC_FORTIFY) && !defined(__BIONIC_NO_STDIO_FORTIFY)
42
43 #if __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
44 /* No diag -- clang diagnoses misuses of this on its own. */
45 __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)46 int vsnprintf(char* const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest, size_t size, const char* _Nonnull format, va_list ap)
47 __diagnose_as_builtin(__builtin_vsnprintf, 1, 2, 3, 4)
48 __overloadable {
49 return __builtin___vsnprintf_chk(dest, size, 0, __bos(dest), format, ap);
50 }
51
52 __BIONIC_FORTIFY_INLINE __printflike(2, 0)
vsprintf(char * const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest,const char * _Nonnull format,va_list ap)53 int vsprintf(char* const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest, const char* _Nonnull format, va_list ap) __overloadable {
54 return __builtin___vsprintf_chk(dest, 0, __bos(dest), format, ap);
55 }
56 #endif
57
58 __BIONIC_ERROR_FUNCTION_VISIBILITY
59 int sprintf(char* __BIONIC_COMPLICATED_NULLNESS dest, const char* _Nonnull format)
60 __overloadable
61 __enable_if(__bos_unevaluated_lt(__bos(dest), __builtin_strlen(format)),
62 "format string will always overflow destination buffer")
63 __errorattr("format string will always overflow destination buffer");
64
65 #if __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
66 __BIONIC_FORTIFY_VARIADIC __printflike(2, 3)
sprintf(char * const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest,const char * _Nonnull format,...)67 int sprintf(char* const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest, const char* _Nonnull format, ...) __overloadable {
68 va_list va;
69 va_start(va, format);
70 int result = __builtin___vsprintf_chk(dest, 0, __bos(dest), format, va);
71 va_end(va);
72 return result;
73 }
74
75 /* No diag -- clang diagnoses misuses of this on its own. */
76 __BIONIC_FORTIFY_VARIADIC __printflike(3, 4)
snprintf(char * const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest,size_t size,const char * _Nonnull format,...)77 int snprintf(char* const __BIONIC_COMPLICATED_NULLNESS __pass_object_size dest, size_t size, const char* _Nonnull format, ...)
78 __diagnose_as_builtin(__builtin_snprintf, 1, 2, 3)
79 __overloadable {
80 va_list va;
81 va_start(va, format);
82 int result = __builtin___vsnprintf_chk(dest, size, 0, __bos(dest), format, va);
83 va_end(va);
84 return result;
85 }
86 #endif
87
88 #define __bos_trivially_ge_mul(bos_val, size, count) \
89 __bos_dynamic_check_impl_and(bos_val, >=, (size) * (count), \
90 !__unsafe_check_mul_overflow(size, count))
91
92 __BIONIC_FORTIFY_INLINE
fread(void * const _Nonnull __pass_object_size0 buf,size_t size,size_t count,FILE * _Nonnull stream)93 size_t fread(void* const _Nonnull __pass_object_size0 buf, size_t size, size_t count, FILE* _Nonnull stream)
94 __overloadable
95 __clang_error_if(__unsafe_check_mul_overflow(size, count),
96 "in call to 'fread', size * count overflows")
97 __clang_error_if(__bos_unevaluated_lt(__bos0(buf), size * count),
98 "in call to 'fread', size * count is too large for the given buffer") {
99 #if __ANDROID_API__ >= 24 && __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
100 size_t bos = __bos0(buf);
101
102 if (!__bos_trivially_ge_mul(bos, size, count)) {
103 return __fread_chk(buf, size, count, stream, bos);
104 }
105 #endif
106 return __call_bypassing_fortify(fread)(buf, size, count, stream);
107 }
108
109 __BIONIC_FORTIFY_INLINE
fwrite(const void * const _Nonnull __pass_object_size0 buf,size_t size,size_t count,FILE * _Nonnull stream)110 size_t fwrite(const void* const _Nonnull __pass_object_size0 buf, size_t size, size_t count, FILE* _Nonnull stream)
111 __overloadable
112 __clang_error_if(__unsafe_check_mul_overflow(size, count),
113 "in call to 'fwrite', size * count overflows")
114 __clang_error_if(__bos_unevaluated_lt(__bos0(buf), size * count),
115 "in call to 'fwrite', size * count is too large for the given buffer") {
116 #if __ANDROID_API__ >= 24 && __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
117 size_t bos = __bos0(buf);
118
119 if (!__bos_trivially_ge_mul(bos, size, count)) {
120 return __fwrite_chk(buf, size, count, stream, bos);
121 }
122 #endif
123 return __call_bypassing_fortify(fwrite)(buf, size, count, stream);
124 }
125 #undef __bos_trivially_ge_mul
126
127 __BIONIC_FORTIFY_INLINE
fgets(char * const _Nonnull __pass_object_size dest,int size,FILE * _Nonnull stream)128 char* _Nullable fgets(char* const _Nonnull __pass_object_size dest, int size, FILE* _Nonnull stream)
129 __overloadable
130 __clang_error_if(size < 0, "in call to 'fgets', size should not be negative")
131 __clang_error_if(__bos_unevaluated_lt(__bos(dest), size),
132 "in call to 'fgets', size is larger than the destination buffer") {
133 #if __BIONIC_FORTIFY_RUNTIME_CHECKS_ENABLED
134 size_t bos = __bos(dest);
135
136 if (!__bos_dynamic_check_impl_and(bos, >=, (size_t)size, size >= 0)) {
137 return __fgets_chk(dest, size, stream, bos);
138 }
139 #endif
140 return __call_bypassing_fortify(fgets)(dest, size, stream);
141 }
142
143 #endif /* defined(__BIONIC_FORTIFY) */
144