1 //===-- dfsan_interface.h -------------------------------------------------===//
3 // This file is distributed under the University of Illinois Open Source
4 // License. See LICENSE.TXT for details.
6 //===----------------------------------------------------------------------===//
8 // This file is a part of DataFlowSanitizer.
10 // Public interface header.
11 //===----------------------------------------------------------------------===//
12 #ifndef DFSAN_INTERFACE_H
13 #define DFSAN_INTERFACE_H
17 #include <sanitizer/common_interface_defs.h>
23 typedef uint16_t dfsan_label
;
25 /// Stores information associated with a specific label identifier. A label
26 /// may be a base label created using dfsan_create_label, with associated
27 /// text description and user data, or an automatically created union label,
28 /// which represents the union of two label identifiers (which may themselves
29 /// be base or union labels).
30 struct dfsan_label_info
{
31 // Fields for union labels, set to 0 for base labels.
35 // Fields for base labels.
40 /// Signature of the callback argument to dfsan_set_write_callback().
41 typedef void (*dfsan_write_callback_t
)(int fd
, const void *buf
, size_t count
);
43 /// Computes the union of \c l1 and \c l2, possibly creating a union label in
45 dfsan_label
dfsan_union(dfsan_label l1
, dfsan_label l2
);
47 /// Creates and returns a base label with the given description and user data.
48 dfsan_label
dfsan_create_label(const char *desc
, void *userdata
);
50 /// Sets the label for each address in [addr,addr+size) to \c label.
51 void dfsan_set_label(dfsan_label label
, void *addr
, size_t size
);
53 /// Sets the label for each address in [addr,addr+size) to the union of the
54 /// current label for that address and \c label.
55 void dfsan_add_label(dfsan_label label
, void *addr
, size_t size
);
57 /// Retrieves the label associated with the given data.
59 /// The type of 'data' is arbitrary. The function accepts a value of any type,
60 /// which can be truncated or extended (implicitly or explicitly) as necessary.
61 /// The truncation/extension operations will preserve the label of the original
63 dfsan_label
dfsan_get_label(long data
);
65 /// Retrieves the label associated with the data at the given address.
66 dfsan_label
dfsan_read_label(const void *addr
, size_t size
);
68 /// Retrieves a pointer to the dfsan_label_info struct for the given label.
69 const struct dfsan_label_info
*dfsan_get_label_info(dfsan_label label
);
71 /// Returns whether the given label label contains the label elem.
72 int dfsan_has_label(dfsan_label label
, dfsan_label elem
);
74 /// If the given label label contains a label with the description desc, returns
75 /// that label, else returns 0.
76 dfsan_label
dfsan_has_label_with_desc(dfsan_label label
, const char *desc
);
78 /// Returns the number of labels allocated.
79 size_t dfsan_get_label_count(void);
81 /// Sets a callback to be invoked on calls to write(). The callback is invoked
82 /// before the write is done. The write is not guaranteed to succeed when the
83 /// callback executes. Pass in NULL to remove any callback.
84 void dfsan_set_write_callback(dfsan_write_callback_t labeled_write_callback
);
86 /// Writes the labels currently used by the program to the given file
87 /// descriptor. The lines of the output have the following format:
89 /// <label> <parent label 1> <parent label 2> <label description if any>
90 void dfsan_dump_labels(int fd
);
92 /// Interceptor hooks.
93 /// Whenever a dfsan's custom function is called the corresponding
94 /// hook is called it non-zero. The hooks should be defined by the user.
95 /// The primary use case is taint-guided fuzzing, where the fuzzer
96 /// needs to see the parameters of the function and the labels.
97 /// FIXME: implement more hooks.
98 void dfsan_weak_hook_memcmp(void *caller_pc
, const void *s1
, const void *s2
,
99 size_t n
, dfsan_label s1_label
,
100 dfsan_label s2_label
, dfsan_label n_label
);
101 void dfsan_weak_hook_strncmp(void *caller_pc
, const char *s1
, const char *s2
,
102 size_t n
, dfsan_label s1_label
,
103 dfsan_label s2_label
, dfsan_label n_label
);
107 template <typename T
>
108 void dfsan_set_label(dfsan_label label
, T
&data
) { // NOLINT
109 dfsan_set_label(label
, (void *)&data
, sizeof(T
));
114 #endif // DFSAN_INTERFACE_H