1 //===-- dfsan_interface.h -------------------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is a part of DataFlowSanitizer.
12 // Public interface header.
13 //===----------------------------------------------------------------------===//
14 #ifndef DFSAN_INTERFACE_H
15 #define DFSAN_INTERFACE_H
19 #include <sanitizer/common_interface_defs.h>
25 typedef uint16_t dfsan_label;
27 /// Stores information associated with a specific label identifier. A label
28 /// may be a base label created using dfsan_create_label, with associated
29 /// text description and user data, or an automatically created union label,
30 /// which represents the union of two label identifiers (which may themselves
31 /// be base or union labels).
32 struct dfsan_label_info {
33 // Fields for union labels, set to 0 for base labels.
37 // Fields for base labels.
42 /// Signature of the callback argument to dfsan_set_write_callback().
43 typedef void (*dfsan_write_callback_t)(int fd, const void *buf, size_t count);
45 /// Computes the union of \c l1 and \c l2, possibly creating a union label in
47 dfsan_label dfsan_union(dfsan_label l1, dfsan_label l2);
49 /// Creates and returns a base label with the given description and user data.
50 dfsan_label dfsan_create_label(const char *desc, void *userdata);
52 /// Sets the label for each address in [addr,addr+size) to \c label.
53 void dfsan_set_label(dfsan_label label, void *addr, size_t size);
55 /// Sets the label for each address in [addr,addr+size) to the union of the
56 /// current label for that address and \c label.
57 void dfsan_add_label(dfsan_label label, void *addr, size_t size);
59 /// Retrieves the label associated with the given data.
61 /// The type of 'data' is arbitrary. The function accepts a value of any type,
62 /// which can be truncated or extended (implicitly or explicitly) as necessary.
63 /// The truncation/extension operations will preserve the label of the original
65 dfsan_label dfsan_get_label(long data);
67 /// Retrieves the label associated with the data at the given address.
68 dfsan_label dfsan_read_label(const void *addr, size_t size);
70 /// Retrieves a pointer to the dfsan_label_info struct for the given label.
71 const struct dfsan_label_info *dfsan_get_label_info(dfsan_label label);
73 /// Returns whether the given label label contains the label elem.
74 int dfsan_has_label(dfsan_label label, dfsan_label elem);
76 /// If the given label label contains a label with the description desc, returns
77 /// that label, else returns 0.
78 dfsan_label dfsan_has_label_with_desc(dfsan_label label, const char *desc);
80 /// Returns the number of labels allocated.
81 size_t dfsan_get_label_count(void);
83 /// Sets a callback to be invoked on calls to write(). The callback is invoked
84 /// before the write is done. The write is not guaranteed to succeed when the
85 /// callback executes. Pass in NULL to remove any callback.
86 void dfsan_set_write_callback(dfsan_write_callback_t labeled_write_callback);
88 /// Writes the labels currently used by the program to the given file
89 /// descriptor. The lines of the output have the following format:
91 /// <label> <parent label 1> <parent label 2> <label description if any>
92 void dfsan_dump_labels(int fd);
94 /// Whenever a dfsan's custom function is called the corresponding
95 /// hook is called it non-zero. The hooks should be defined by the user.
96 /// The primary use case is taint-guided fuzzing, where the fuzzer
97 /// needs to see the parameters of the function and the labels.
98 /// FIXME: implement more hooks.
101 void dfsan_weak_hook_memcmp(void *caller_pc, const void *s1, const void *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