1 #include <stdio.h>
2 #include <assert.h>
3
4 #include "zbuild.h"
5 #ifdef ZLIB_COMPAT
6 # include "zlib.h"
7 #else
8 # include "zlib-ng.h"
9 #endif
10
11 #define CHECK_ERR(err, msg) { \
12 if (err != Z_OK) { \
13 fprintf(stderr, "%s error: %d\n", msg, err); \
14 exit(1); \
15 } \
16 }
17
18 static const uint8_t *data;
19 static size_t dataLen;
20 static alloc_func zalloc = NULL;
21 static free_func zfree = NULL;
22
23 /* ===========================================================================
24 * Test deflate() with full flush
25 */
test_flush(unsigned char * compr,z_size_t * comprLen)26 void test_flush(unsigned char *compr, z_size_t *comprLen) {
27 PREFIX3(stream) c_stream; /* compression stream */
28 int err;
29 unsigned int len = (unsigned int)dataLen;
30
31 c_stream.zalloc = zalloc;
32 c_stream.zfree = zfree;
33 c_stream.opaque = (void *)0;
34
35 err = PREFIX(deflateInit)(&c_stream, Z_DEFAULT_COMPRESSION);
36 CHECK_ERR(err, "deflateInit");
37
38 c_stream.next_in = (z_const unsigned char *)data;
39 c_stream.next_out = compr;
40 c_stream.avail_in = 3;
41 c_stream.avail_out = (unsigned int)*comprLen;
42 err = PREFIX(deflate)(&c_stream, Z_FULL_FLUSH);
43 CHECK_ERR(err, "deflate flush 1");
44
45 compr[3]++; /* force an error in first compressed block */
46 c_stream.avail_in = len - 3;
47
48 err = PREFIX(deflate)(&c_stream, Z_FINISH);
49 if (err != Z_STREAM_END) {
50 CHECK_ERR(err, "deflate flush 2");
51 }
52 err = PREFIX(deflateEnd)(&c_stream);
53 CHECK_ERR(err, "deflateEnd");
54
55 *comprLen = (z_size_t)c_stream.total_out;
56 }
57
58 /* ===========================================================================
59 * Test inflateSync()
60 */
test_sync(unsigned char * compr,size_t comprLen,unsigned char * uncompr,size_t uncomprLen)61 void test_sync(unsigned char *compr, size_t comprLen, unsigned char *uncompr, size_t uncomprLen) {
62 int err;
63 PREFIX3(stream) d_stream; /* decompression stream */
64
65 d_stream.zalloc = zalloc;
66 d_stream.zfree = zfree;
67 d_stream.opaque = (void *)0;
68
69 d_stream.next_in = compr;
70 d_stream.avail_in = 2; /* just read the zlib header */
71
72 err = PREFIX(inflateInit)(&d_stream);
73 CHECK_ERR(err, "inflateInit");
74
75 d_stream.next_out = uncompr;
76 d_stream.avail_out = (unsigned int)uncomprLen;
77
78 err = PREFIX(inflate)(&d_stream, Z_NO_FLUSH);
79 CHECK_ERR(err, "inflate");
80
81 d_stream.avail_in = (unsigned int)comprLen - 2; /* read all compressed data */
82 err = PREFIX(inflateSync)(&d_stream); /* but skip the damaged part */
83 CHECK_ERR(err, "inflateSync");
84
85 err = PREFIX(inflate)(&d_stream, Z_FINISH);
86 if (err != Z_STREAM_END) {
87 fprintf(stderr, "inflate should report Z_STREAM_END\n");
88 exit(1);
89 }
90 err = PREFIX(inflateEnd)(&d_stream);
91 CHECK_ERR(err, "inflateEnd");
92 }
93
LLVMFuzzerTestOneInput(const uint8_t * d,size_t size)94 int LLVMFuzzerTestOneInput(const uint8_t *d, size_t size) {
95 z_size_t comprLen = 100 + 2 * PREFIX(compressBound)(size);
96 z_size_t uncomprLen = (z_size_t)size;
97 uint8_t *compr, *uncompr;
98
99 /* Discard inputs larger than 1Mb. */
100 static size_t kMaxSize = 1024 * 1024;
101
102 // This test requires at least 3 bytes of input data.
103 if (size <= 3 || size > kMaxSize)
104 return 0;
105
106 data = d;
107 dataLen = size;
108 compr = (uint8_t *)calloc(1, comprLen);
109 uncompr = (uint8_t *)calloc(1, uncomprLen);
110
111 test_flush(compr, &comprLen);
112 test_sync(compr, comprLen, uncompr, uncomprLen);
113
114 free(compr);
115 free(uncompr);
116
117 /* This function must return 0. */
118 return 0;
119 }
120