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 static unsigned int diff;
22
23 /* ===========================================================================
24 * Test deflate() with large buffers and dynamic change of compression level
25 */
test_large_deflate(unsigned char * compr,size_t comprLen,unsigned char * uncompr,size_t uncomprLen)26 void test_large_deflate(unsigned char *compr, size_t comprLen,
27 unsigned char *uncompr, size_t uncomprLen) {
28 z_stream c_stream; /* compression stream */
29 int err;
30
31 c_stream.zalloc = zalloc;
32 c_stream.zfree = zfree;
33 c_stream.opaque = (void *)0;
34
35 err = deflateInit(&c_stream, Z_BEST_COMPRESSION);
36 CHECK_ERR(err, "deflateInit");
37
38 c_stream.next_out = compr;
39 c_stream.avail_out = (unsigned int)comprLen;
40
41 /* At this point, uncompr is still mostly zeroes, so it should compress
42 * very well:
43 */
44 c_stream.next_in = uncompr;
45 c_stream.avail_in = (unsigned int)uncomprLen;
46 err = deflate(&c_stream, Z_NO_FLUSH);
47 CHECK_ERR(err, "deflate large 1");
48 if (c_stream.avail_in != 0) {
49 fprintf(stderr, "deflate not greedy\n");
50 exit(1);
51 }
52
53 /* Feed in already compressed data and switch to no compression: */
54 deflateParams(&c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY);
55 c_stream.next_in = compr;
56 diff = (unsigned int)(c_stream.next_out - compr);
57 c_stream.avail_in = diff;
58 err = deflate(&c_stream, Z_NO_FLUSH);
59 CHECK_ERR(err, "deflate large 2");
60
61 /* Switch back to compressing mode: */
62 deflateParams(&c_stream, Z_BEST_COMPRESSION, Z_FILTERED);
63 c_stream.next_in = uncompr;
64 c_stream.avail_in = (unsigned int)uncomprLen;
65 err = deflate(&c_stream, Z_NO_FLUSH);
66 CHECK_ERR(err, "deflate large 3");
67
68 err = deflate(&c_stream, Z_FINISH);
69 if (err != Z_STREAM_END) {
70 fprintf(stderr, "deflate large should report Z_STREAM_END\n");
71 exit(1);
72 }
73 err = deflateEnd(&c_stream);
74 CHECK_ERR(err, "deflateEnd");
75 }
76
77 /* ===========================================================================
78 * Test inflate() with large buffers
79 */
test_large_inflate(unsigned char * compr,size_t comprLen,unsigned char * uncompr,size_t uncomprLen)80 void test_large_inflate(unsigned char *compr, size_t comprLen,
81 unsigned char *uncompr, size_t uncomprLen) {
82 int err;
83 z_stream d_stream; /* decompression stream */
84
85 d_stream.zalloc = zalloc;
86 d_stream.zfree = zfree;
87 d_stream.opaque = (void *)0;
88
89 d_stream.next_in = compr;
90 d_stream.avail_in = (unsigned int)comprLen;
91
92 err = inflateInit(&d_stream);
93 CHECK_ERR(err, "inflateInit");
94
95 for (;;) {
96 d_stream.next_out = uncompr; /* discard the output */
97 d_stream.avail_out = (unsigned int)uncomprLen;
98 err = inflate(&d_stream, Z_NO_FLUSH);
99 if (err == Z_STREAM_END)
100 break;
101 CHECK_ERR(err, "large inflate");
102 }
103
104 err = inflateEnd(&d_stream);
105 CHECK_ERR(err, "inflateEnd");
106
107 if (d_stream.total_out != 2 * uncomprLen + diff) {
108 fprintf(stderr, "bad large inflate: %zu\n", d_stream.total_out);
109 exit(1);
110 }
111 }
112
LLVMFuzzerTestOneInput(const uint8_t * d,size_t size)113 int LLVMFuzzerTestOneInput(const uint8_t *d, size_t size) {
114 size_t comprLen = 100 + 3 * size;
115 size_t uncomprLen = comprLen;
116 uint8_t *compr, *uncompr;
117
118 /* Discard inputs larger than 512Kb. */
119 static size_t kMaxSize = 512 * 1024;
120
121 if (size < 1 || size > kMaxSize)
122 return 0;
123
124 data = d;
125 dataLen = size;
126 compr = (uint8_t *)calloc(1, comprLen);
127 uncompr = (uint8_t *)calloc(1, uncomprLen);
128
129 test_large_deflate(compr, comprLen, uncompr, uncomprLen);
130 test_large_inflate(compr, comprLen, uncompr, uncomprLen);
131
132 free(compr);
133 free(uncompr);
134
135 /* This function must return 0. */
136 return 0;
137 }
138