xref: /openbmc/u-boot/lib/gunzip.c (revision d928664f)
1 /*
2  * (C) Copyright 2000-2006
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <watchdog.h>
10 #include <command.h>
11 #include <image.h>
12 #include <malloc.h>
13 #include <u-boot/zlib.h>
14 
15 #define	ZALLOC_ALIGNMENT	16
16 #define HEAD_CRC		2
17 #define EXTRA_FIELD		4
18 #define ORIG_NAME		8
19 #define COMMENT			0x10
20 #define RESERVED		0xe0
21 #define DEFLATED		8
22 
23 void *gzalloc(void *x, unsigned items, unsigned size)
24 {
25 	void *p;
26 
27 	size *= items;
28 	size = (size + ZALLOC_ALIGNMENT - 1) & ~(ZALLOC_ALIGNMENT - 1);
29 
30 	p = malloc (size);
31 
32 	return (p);
33 }
34 
35 void gzfree(void *x, void *addr, unsigned nb)
36 {
37 	free (addr);
38 }
39 
40 int gunzip(void *dst, int dstlen, unsigned char *src, unsigned long *lenp)
41 {
42 	int i, flags;
43 
44 	/* skip header */
45 	i = 10;
46 	flags = src[3];
47 	if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
48 		puts ("Error: Bad gzipped data\n");
49 		return (-1);
50 	}
51 	if ((flags & EXTRA_FIELD) != 0)
52 		i = 12 + src[10] + (src[11] << 8);
53 	if ((flags & ORIG_NAME) != 0)
54 		while (src[i++] != 0)
55 			;
56 	if ((flags & COMMENT) != 0)
57 		while (src[i++] != 0)
58 			;
59 	if ((flags & HEAD_CRC) != 0)
60 		i += 2;
61 	if (i >= *lenp) {
62 		puts ("Error: gunzip out of data in header\n");
63 		return (-1);
64 	}
65 
66 	return zunzip(dst, dstlen, src, lenp, 1, i);
67 }
68 
69 /*
70  * Uncompress blocks compressed with zlib without headers
71  */
72 int zunzip(void *dst, int dstlen, unsigned char *src, unsigned long *lenp,
73 						int stoponerr, int offset)
74 {
75 	z_stream s;
76 	int err = 0;
77 	int r;
78 
79 	s.zalloc = gzalloc;
80 	s.zfree = gzfree;
81 
82 	r = inflateInit2(&s, -MAX_WBITS);
83 	if (r != Z_OK) {
84 		printf ("Error: inflateInit2() returned %d\n", r);
85 		return -1;
86 	}
87 	s.next_in = src + offset;
88 	s.avail_in = *lenp - offset;
89 	s.next_out = dst;
90 	s.avail_out = dstlen;
91 	do {
92 		r = inflate(&s, Z_FINISH);
93 		if (stoponerr == 1 && r != Z_STREAM_END &&
94 		    (s.avail_out == 0 || r != Z_BUF_ERROR)) {
95 			printf("Error: inflate() returned %d\n", r);
96 			err = -1;
97 			break;
98 		}
99 		s.avail_in = *lenp - offset - (int)(s.next_out - (unsigned char*)dst);
100 	} while (r == Z_BUF_ERROR);
101 	*lenp = s.next_out - (unsigned char *) dst;
102 	inflateEnd(&s);
103 
104 	return err;
105 }
106