1/* SPDX-License-Identifier: 0BSD */
2
3/*
4 * Private includes and definitions
5 *
6 * Author: Lasse Collin <lasse.collin@tukaani.org>
7 */
8
9#ifndef XZ_PRIVATE_H
10#define XZ_PRIVATE_H
11
12#ifdef __KERNEL__
13# include <linux/xz.h>
14# include <linux/kernel.h>
15# include <linux/unaligned.h>
16 /* XZ_PREBOOT may be defined only via decompress_unxz.c. */
17# ifndef XZ_PREBOOT
18# include <linux/slab.h>
19# include <linux/vmalloc.h>
20# include <linux/string.h>
21# ifdef CONFIG_XZ_DEC_X86
22# define XZ_DEC_X86
23# endif
24# ifdef CONFIG_XZ_DEC_POWERPC
25# define XZ_DEC_POWERPC
26# endif
27# ifdef CONFIG_XZ_DEC_IA64
28# define XZ_DEC_IA64
29# endif
30# ifdef CONFIG_XZ_DEC_ARM
31# define XZ_DEC_ARM
32# endif
33# ifdef CONFIG_XZ_DEC_ARMTHUMB
34# define XZ_DEC_ARMTHUMB
35# endif
36# ifdef CONFIG_XZ_DEC_SPARC
37# define XZ_DEC_SPARC
38# endif
39# ifdef CONFIG_XZ_DEC_ARM64
40# define XZ_DEC_ARM64
41# endif
42# ifdef CONFIG_XZ_DEC_RISCV
43# define XZ_DEC_RISCV
44# endif
45# ifdef CONFIG_XZ_DEC_MICROLZMA
46# define XZ_DEC_MICROLZMA
47# endif
48# define memeq(a, b, size) (memcmp(a, b, size) == 0)
49# define memzero(buf, size) memset(buf, 0, size)
50# endif
51# define get_le32(p) le32_to_cpup((const uint32_t *)(p))
52#else
53 /*
54 * For userspace builds, use a separate header to define the required
55 * macros and functions. This makes it easier to adapt the code into
56 * different environments and avoids clutter in the Linux kernel tree.
57 */
58# include "xz_config.h"
59#endif
60
61/* If no specific decoding mode is requested, enable support for all modes. */
62#if !defined(XZ_DEC_SINGLE) && !defined(XZ_DEC_PREALLOC) \
63 && !defined(XZ_DEC_DYNALLOC)
64# define XZ_DEC_SINGLE
65# define XZ_DEC_PREALLOC
66# define XZ_DEC_DYNALLOC
67#endif
68
69/*
70 * The DEC_IS_foo(mode) macros are used in "if" statements. If only some
71 * of the supported modes are enabled, these macros will evaluate to true or
72 * false at compile time and thus allow the compiler to omit unneeded code.
73 */
74#ifdef XZ_DEC_SINGLE
75# define DEC_IS_SINGLE(mode) ((mode) == XZ_SINGLE)
76#else
77# define DEC_IS_SINGLE(mode) (false)
78#endif
79
80#ifdef XZ_DEC_PREALLOC
81# define DEC_IS_PREALLOC(mode) ((mode) == XZ_PREALLOC)
82#else
83# define DEC_IS_PREALLOC(mode) (false)
84#endif
85
86#ifdef XZ_DEC_DYNALLOC
87# define DEC_IS_DYNALLOC(mode) ((mode) == XZ_DYNALLOC)
88#else
89# define DEC_IS_DYNALLOC(mode) (false)
90#endif
91
92#if !defined(XZ_DEC_SINGLE)
93# define DEC_IS_MULTI(mode) (true)
94#elif defined(XZ_DEC_PREALLOC) || defined(XZ_DEC_DYNALLOC)
95# define DEC_IS_MULTI(mode) ((mode) != XZ_SINGLE)
96#else
97# define DEC_IS_MULTI(mode) (false)
98#endif
99
100/*
101 * If any of the BCJ filter decoders are wanted, define XZ_DEC_BCJ.
102 * XZ_DEC_BCJ is used to enable generic support for BCJ decoders.
103 */
104#ifndef XZ_DEC_BCJ
105# if defined(XZ_DEC_X86) || defined(XZ_DEC_POWERPC) \
106 || defined(XZ_DEC_IA64) \
107 || defined(XZ_DEC_ARM) || defined(XZ_DEC_ARMTHUMB) \
108 || defined(XZ_DEC_SPARC) || defined(XZ_DEC_ARM64) \
109 || defined(XZ_DEC_RISCV)
110# define XZ_DEC_BCJ
111# endif
112#endif
113
114/*
115 * Allocate memory for LZMA2 decoder. xz_dec_lzma2_reset() must be used
116 * before calling xz_dec_lzma2_run().
117 */
118struct xz_dec_lzma2 *xz_dec_lzma2_create(enum xz_mode mode, uint32_t dict_max);
119
120/*
121 * Decode the LZMA2 properties (one byte) and reset the decoder. Return
122 * XZ_OK on success, XZ_MEMLIMIT_ERROR if the preallocated dictionary is not
123 * big enough, and XZ_OPTIONS_ERROR if props indicates something that this
124 * decoder doesn't support.
125 */
126enum xz_ret xz_dec_lzma2_reset(struct xz_dec_lzma2 *s, uint8_t props);
127
128/* Decode raw LZMA2 stream from b->in to b->out. */
129enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s, struct xz_buf *b);
130
131/* Free the memory allocated for the LZMA2 decoder. */
132void xz_dec_lzma2_end(struct xz_dec_lzma2 *s);
133
134#ifdef XZ_DEC_BCJ
135/*
136 * Allocate memory for BCJ decoders. xz_dec_bcj_reset() must be used before
137 * calling xz_dec_bcj_run().
138 */
139struct xz_dec_bcj *xz_dec_bcj_create(bool single_call);
140
141/*
142 * Decode the Filter ID of a BCJ filter. This implementation doesn't
143 * support custom start offsets, so no decoding of Filter Properties
144 * is needed. Returns XZ_OK if the given Filter ID is supported.
145 * Otherwise XZ_OPTIONS_ERROR is returned.
146 */
147enum xz_ret xz_dec_bcj_reset(struct xz_dec_bcj *s, uint8_t id);
148
149/*
150 * Decode raw BCJ + LZMA2 stream. This must be used only if there actually is
151 * a BCJ filter in the chain. If the chain has only LZMA2, xz_dec_lzma2_run()
152 * must be called directly.
153 */
154enum xz_ret xz_dec_bcj_run(struct xz_dec_bcj *s, struct xz_dec_lzma2 *lzma2,
155 struct xz_buf *b);
156
157/* Free the memory allocated for the BCJ filters. */
158#define xz_dec_bcj_end(s) kfree(s)
159#endif
160
161#endif
162