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
9 #include "zbuild.h"
10 #ifdef ZLIB_COMPAT
11 # include "zlib.h"
12 #else
13 # include "zlib-ng.h"
14 #endif
15
16 #define CHECK_ERR(err, msg) { \
17 if (err != Z_OK) { \
18 fprintf(stderr, "%s error: %d\n", msg, err); \
19 exit(1); \
20 } \
21 }
22
23 static const uint8_t *data;
24 static size_t dataLen;
25 static alloc_func zalloc = NULL;
26 static free_func zfree = NULL;
27
28 /* ===========================================================================
29 * Test deflate() with full flush
30 */
test_flush(unsigned char * compr,z_size_t * comprLen)31 void test_flush(unsigned char *compr, z_size_t *comprLen) {
32 PREFIX3(stream) c_stream; /* compression stream */
33 int err;
34 unsigned int len = (unsigned int)dataLen;
35
36 c_stream.zalloc = zalloc;
37 c_stream.zfree = zfree;
38 c_stream.opaque = (void *)0;
39
40 err = PREFIX(deflateInit)(&c_stream, Z_DEFAULT_COMPRESSION);
41 CHECK_ERR(err, "deflateInit");
42
43 c_stream.next_in = (z_const unsigned char *)data;
44 c_stream.next_out = compr;
45 c_stream.avail_in = 3;
46 c_stream.avail_out = (unsigned int)*comprLen;
47 err = PREFIX(deflate)(&c_stream, Z_FULL_FLUSH);
48 CHECK_ERR(err, "deflate flush 1");
49
50 compr[3]++; /* force an error in first compressed block */
51 c_stream.avail_in = len - 3;
52
53 err = PREFIX(deflate)(&c_stream, Z_FINISH);
54 if (err != Z_STREAM_END) {
55 CHECK_ERR(err, "deflate flush 2");
56 }
57 err = PREFIX(deflateEnd)(&c_stream);
58 CHECK_ERR(err, "deflateEnd");
59
60 *comprLen = (z_size_t)c_stream.total_out;
61 }
62
63 /* ===========================================================================
64 * Test inflateSync()
65 */
test_sync(unsigned char * compr,size_t comprLen,unsigned char * uncompr,size_t uncomprLen)66 void test_sync(unsigned char *compr, size_t comprLen, unsigned char *uncompr, size_t uncomprLen) {
67 int err;
68 PREFIX3(stream) d_stream; /* decompression stream */
69
70 d_stream.zalloc = zalloc;
71 d_stream.zfree = zfree;
72 d_stream.opaque = (void *)0;
73
74 d_stream.next_in = compr;
75 d_stream.avail_in = 2; /* just read the zlib header */
76
77 err = PREFIX(inflateInit)(&d_stream);
78 CHECK_ERR(err, "inflateInit");
79
80 d_stream.next_out = uncompr;
81 d_stream.avail_out = (unsigned int)uncomprLen;
82
83 err = PREFIX(inflate)(&d_stream, Z_NO_FLUSH);
84 CHECK_ERR(err, "inflate");
85
86 d_stream.avail_in = (unsigned int)comprLen - 2; /* read all compressed data */
87 err = PREFIX(inflateSync)(&d_stream); /* but skip the damaged part */
88 CHECK_ERR(err, "inflateSync");
89
90 err = PREFIX(inflate)(&d_stream, Z_FINISH);
91 if (err != Z_STREAM_END) {
92 fprintf(stderr, "inflate should report Z_STREAM_END\n");
93 exit(1);
94 }
95 err = PREFIX(inflateEnd)(&d_stream);
96 CHECK_ERR(err, "inflateEnd");
97 }
98
LLVMFuzzerTestOneInput(const uint8_t * d,size_t size)99 int LLVMFuzzerTestOneInput(const uint8_t *d, size_t size) {
100 z_size_t comprLen = 100 + 2 * PREFIX(compressBound)(size);
101 z_size_t uncomprLen = (z_size_t)size;
102 uint8_t *compr, *uncompr;
103
104 /* Discard inputs larger than 1Mb. */
105 static size_t kMaxSize = 1024 * 1024;
106
107 // This test requires at least 3 bytes of input data.
108 if (size <= 3 || size > kMaxSize)
109 return 0;
110
111 data = d;
112 dataLen = size;
113 compr = (uint8_t *)calloc(1, comprLen);
114 uncompr = (uint8_t *)calloc(1, uncomprLen);
115
116 test_flush(compr, &comprLen);
117 test_sync(compr, comprLen, uncompr, uncomprLen);
118
119 free(compr);
120 free(uncompr);
121
122 /* This function must return 0. */
123 return 0;
124 }
125