1#ifdef STATIC
2#define PREBOOT
3/* Pre-boot environment: included */
4
5/* prevent inclusion of _LINUX_KERNEL_H in pre-boot environment: lots
6 * errors about console_printk etc... on ARM */
7#define _LINUX_KERNEL_H
8
9#include "zlib_inflate/inftrees.c"
10#include "zlib_inflate/inffast.c"
11#include "zlib_inflate/inflate.c"
12
13#else /* STATIC */
14/* initramfs et al: linked */
15
16#include <linux/zutil.h>
17
18#include "zlib_inflate/inftrees.h"
19#include "zlib_inflate/inffast.h"
20#include "zlib_inflate/inflate.h"
21
22#include "zlib_inflate/infutil.h"
23#include <linux/decompress/inflate.h>
24
25#endif /* STATIC */
26
27#include <linux/decompress/mm.h>
28
29#define GZIP_IOBUF_SIZE (16*1024)
30
31static long INIT nofill(void *buffer, unsigned long len)
32{
33	return -1;
34}
35
36/* Included from initramfs et al code */
37STATIC int INIT __gunzip(unsigned char *buf, long len,
38		       long (*fill)(void*, unsigned long),
39		       long (*flush)(void*, unsigned long),
40		       unsigned char *out_buf, long out_len,
41		       long *pos,
42		       void(*error)(char *x)) {
43	u8 *zbuf;
44	struct z_stream_s *strm;
45	int rc;
46
47	rc = -1;
48	if (flush) {
49		out_len = 0x8000; /* 32 K */
50		out_buf = malloc(out_len);
51	} else {
52		if (!out_len)
53			out_len = ((size_t)~0) - (size_t)out_buf; /* no limit */
54	}
55	if (!out_buf) {
56		error("Out of memory while allocating output buffer");
57		goto gunzip_nomem1;
58	}
59
60	if (buf)
61		zbuf = buf;
62	else {
63		zbuf = malloc(GZIP_IOBUF_SIZE);
64		len = 0;
65	}
66	if (!zbuf) {
67		error("Out of memory while allocating input buffer");
68		goto gunzip_nomem2;
69	}
70
71	strm = malloc(sizeof(*strm));
72	if (strm == NULL) {
73		error("Out of memory while allocating z_stream");
74		goto gunzip_nomem3;
75	}
76
77	strm->workspace = malloc(flush ? zlib_inflate_workspacesize() :
78				 sizeof(struct inflate_state));
79	if (strm->workspace == NULL) {
80		error("Out of memory while allocating workspace");
81		goto gunzip_nomem4;
82	}
83
84	if (!fill)
85		fill = nofill;
86
87	if (len == 0)
88		len = fill(zbuf, GZIP_IOBUF_SIZE);
89
90	/* verify the gzip header */
91	if (len < 10 ||
92	   zbuf[0] != 0x1f || zbuf[1] != 0x8b || zbuf[2] != 0x08) {
93		if (pos)
94			*pos = 0;
95		error("Not a gzip file");
96		goto gunzip_5;
97	}
98
99	/* skip over gzip header (1f,8b,08... 10 bytes total +
100	 * possible asciz filename)
101	 */
102	strm->next_in = zbuf + 10;
103	strm->avail_in = len - 10;
104	/* skip over asciz filename */
105	if (zbuf[3] & 0x8) {
106		do {
107			/*
108			 * If the filename doesn't fit into the buffer,
109			 * the file is very probably corrupt. Don't try
110			 * to read more data.
111			 */
112			if (strm->avail_in == 0) {
113				error("header error");
114				goto gunzip_5;
115			}
116			--strm->avail_in;
117		} while (*strm->next_in++);
118	}
119
120	strm->next_out = out_buf;
121	strm->avail_out = out_len;
122
123	rc = zlib_inflateInit2(strm, -MAX_WBITS);
124
125	if (!flush) {
126		WS(strm)->inflate_state.wsize = 0;
127		WS(strm)->inflate_state.window = NULL;
128	}
129
130	while (rc == Z_OK) {
131		if (strm->avail_in == 0) {
132			/* TODO: handle case where both pos and fill are set */
133			len = fill(zbuf, GZIP_IOBUF_SIZE);
134			if (len < 0) {
135				rc = -1;
136				error("read error");
137				break;
138			}
139			strm->next_in = zbuf;
140			strm->avail_in = len;
141		}
142		rc = zlib_inflate(strm, 0);
143
144		/* Write any data generated */
145		if (flush && strm->next_out > out_buf) {
146			long l = strm->next_out - out_buf;
147			if (l != flush(out_buf, l)) {
148				rc = -1;
149				error("write error");
150				break;
151			}
152			strm->next_out = out_buf;
153			strm->avail_out = out_len;
154		}
155
156		/* after Z_FINISH, only Z_STREAM_END is "we unpacked it all" */
157		if (rc == Z_STREAM_END) {
158			rc = 0;
159			break;
160		} else if (rc != Z_OK) {
161			error("uncompression error");
162			rc = -1;
163		}
164	}
165
166	zlib_inflateEnd(strm);
167	if (pos)
168		/* add + 8 to skip over trailer */
169		*pos = strm->next_in - zbuf+8;
170
171gunzip_5:
172	free(strm->workspace);
173gunzip_nomem4:
174	free(strm);
175gunzip_nomem3:
176	if (!buf)
177		free(zbuf);
178gunzip_nomem2:
179	if (flush)
180		free(out_buf);
181gunzip_nomem1:
182	return rc; /* returns Z_OK (0) if successful */
183}
184
185#ifndef PREBOOT
186STATIC int INIT gunzip(unsigned char *buf, long len,
187		       long (*fill)(void*, unsigned long),
188		       long (*flush)(void*, unsigned long),
189		       unsigned char *out_buf,
190		       long *pos,
191		       void (*error)(char *x))
192{
193	return __gunzip(buf, len, fill, flush, out_buf, 0, pos, error);
194}
195#else
196STATIC int INIT __decompress(unsigned char *buf, long len,
197			   long (*fill)(void*, unsigned long),
198			   long (*flush)(void*, unsigned long),
199			   unsigned char *out_buf, long out_len,
200			   long *pos,
201			   void (*error)(char *x))
202{
203	return __gunzip(buf, len, fill, flush, out_buf, out_len, pos, error);
204}
205#endif
206