1 #include <stdio.h>
2 #include <stddef.h>
3 #include <stdint.h>
4 #include <string.h>
5 #include <assert.h>
6 #include <stdlib.h>
7 #include <inttypes.h>
8 #include "zlib.h"
9
10 #define CHECK_ERR(err, msg) { \
11 if (err != Z_OK) { \
12 fprintf(stderr, "%s error: %d\n", msg, err); \
13 exit(1); \
14 } \
15 }
16
17 static const uint8_t *data;
18 static size_t dataLen;
19 static alloc_func zalloc = NULL;
20 static free_func zfree = NULL;
21
22 /* ===========================================================================
23 * Test deflate() with full flush
24 */
test_flush(unsigned char * compr,z_size_t * comprLen)25 void test_flush(unsigned char *compr, z_size_t *comprLen) {
26 z_stream c_stream; /* compression stream */
27 int err;
28 unsigned int len = dataLen;
29
30 c_stream.zalloc = zalloc;
31 c_stream.zfree = zfree;
32 c_stream.opaque = (void *)0;
33
34 err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
35 CHECK_ERR(err, "deflateInit");
36
37 c_stream.next_in = (Bytef *)data;
38 c_stream.next_out = compr;
39 c_stream.avail_in = 3;
40 c_stream.avail_out = (unsigned int)*comprLen;
41 err = deflate(&c_stream, Z_FULL_FLUSH);
42 CHECK_ERR(err, "deflate flush 1");
43
44 compr[3]++; /* force an error in first compressed block */
45 c_stream.avail_in = len - 3;
46
47 err = deflate(&c_stream, Z_FINISH);
48 if (err != Z_STREAM_END) {
49 CHECK_ERR(err, "deflate flush 2");
50 }
51 err = deflateEnd(&c_stream);
52 CHECK_ERR(err, "deflateEnd");
53
54 *comprLen = (z_size_t)c_stream.total_out;
55 }
56
57 /* ===========================================================================
58 * Test inflateSync()
59 */
test_sync(unsigned char * compr,size_t comprLen,unsigned char * uncompr,size_t uncomprLen)60 void test_sync(unsigned char *compr, size_t comprLen, unsigned char *uncompr,
61 size_t uncomprLen) {
62 int err;
63 z_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 = 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 = 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 = inflateSync(&d_stream); /* but skip the damaged part */
83 CHECK_ERR(err, "inflateSync");
84
85 err = inflate(&d_stream, Z_FINISH);
86 if (err != Z_DATA_ERROR) {
87 fprintf(stderr, "inflate should report DATA_ERROR\n");
88 /* Because of incorrect adler32 */
89 exit(1);
90 }
91 err = inflateEnd(&d_stream);
92 CHECK_ERR(err, "inflateEnd");
93 }
94
LLVMFuzzerTestOneInput(const uint8_t * d,size_t size)95 int LLVMFuzzerTestOneInput(const uint8_t *d, size_t size) {
96 size_t comprLen = 100 + 2 * compressBound(size);
97 size_t uncomprLen = size;
98 uint8_t *compr, *uncompr;
99
100 /* Discard inputs larger than 1Mb. */
101 static size_t kMaxSize = 1024 * 1024;
102
103 // This test requires at least 3 bytes of input data.
104 if (size <= 3 || size > kMaxSize)
105 return 0;
106
107 data = d;
108 dataLen = size;
109 compr = (uint8_t *)calloc(1, comprLen);
110 uncompr = (uint8_t *)calloc(1, uncomprLen);
111
112 test_flush(compr, &comprLen);
113 test_sync(compr, comprLen, uncompr, uncomprLen);
114
115 free(compr);
116 free(uncompr);
117
118 /* This function must return 0. */
119 return 0;
120 }
121