openwrt/target/linux/generic-2.6/patches-2.6.30/052-pcomp_lzma_support.patch

822 lines
18 KiB
Diff

--- /dev/null
+++ b/crypto/unlzma.c
@@ -0,0 +1,710 @@
+/*
+ * LZMA uncompresion module for pcomp
+ * Copyright (C) 2009 Felix Fietkau <nbd@openwrt.org>
+ *
+ * Based on:
+ * Initial Linux kernel adaptation
+ * Copyright (C) 2006 Alain < alain@knaff.lu >
+ *
+ * Based on small lzma deflate implementation/Small range coder
+ * implementation for lzma.
+ * Copyright (C) 2006 Aurelien Jacobs < aurel@gnuage.org >
+ *
+ * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
+ * Copyright (C) 1999-2005 Igor Pavlov
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * FIXME: the current implementation assumes that the caller will
+ * not free any output buffers until the whole decompression has been
+ * completed. This is necessary, because LZMA looks back at old output
+ * instead of doing a separate dictionary allocation, which saves RAM.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/interrupt.h>
+#include <linux/mm.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <linux/kthread.h>
+
+#include <crypto/internal/compress.h>
+#include "unlzma.h"
+
+static int instance = 0;
+
+struct unlzma_buffer {
+ struct unlzma_buffer *last;
+ int offset;
+ int size;
+ u8 *ptr;
+};
+
+struct unlzma_ctx {
+ struct task_struct *thread;
+ wait_queue_head_t next_req;
+ struct mutex mutex;
+ bool active;
+ bool cancel;
+
+ const u8 *next_in;
+ int avail_in;
+
+ u8 *next_out;
+ int avail_out;
+
+ /* reader state */
+ u32 code;
+ u32 range;
+ u32 bound;
+
+ /* writer state */
+ u8 previous_byte;
+ ssize_t pos;
+ struct unlzma_buffer *head;
+
+ /* cstate */
+ int state;
+ u32 rep0, rep1, rep2, rep3;
+
+ u32 dict_size;
+
+ void *workspace;
+ int workspace_size;
+};
+
+static inline bool
+unlzma_should_stop(struct unlzma_ctx *ctx)
+{
+ return unlikely(kthread_should_stop() || ctx->cancel);
+}
+
+static void
+unlzma_request_buffer(struct unlzma_ctx *ctx, int *avail)
+{
+ mutex_unlock(&ctx->mutex);
+ wait_event(ctx->next_req, unlzma_should_stop(ctx) || (*avail > 0));
+ mutex_lock(&ctx->mutex);
+}
+
+static u8
+rc_read(struct unlzma_ctx *ctx)
+{
+ if (unlikely(ctx->avail_in <= 0))
+ unlzma_request_buffer(ctx, &ctx->avail_in);
+
+ if (unlzma_should_stop(ctx))
+ return 0;
+
+ ctx->avail_in--;
+ return *(ctx->next_in++);
+}
+
+
+static inline void
+rc_get_code(struct unlzma_ctx *ctx)
+{
+ ctx->code = (ctx->code << 8) | rc_read(ctx);
+}
+
+static void
+rc_normalize(struct unlzma_ctx *ctx)
+{
+ if (ctx->range < (1 << RC_TOP_BITS)) {
+ ctx->range <<= 8;
+ rc_get_code(ctx);
+ }
+}
+
+static int
+rc_is_bit_0(struct unlzma_ctx *ctx, u16 *p)
+{
+ rc_normalize(ctx);
+ ctx->bound = *p * (ctx->range >> RC_MODEL_TOTAL_BITS);
+ return ctx->code < ctx->bound;
+}
+
+static void
+rc_update_bit_0(struct unlzma_ctx *ctx, u16 *p)
+{
+ ctx->range = ctx->bound;
+ *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
+}
+
+static void
+rc_update_bit_1(struct unlzma_ctx *ctx, u16 *p)
+{
+ ctx->range -= ctx->bound;
+ ctx->code -= ctx->bound;
+ *p -= *p >> RC_MOVE_BITS;
+}
+
+static bool
+rc_get_bit(struct unlzma_ctx *ctx, u16 *p, int *symbol)
+{
+ if (rc_is_bit_0(ctx, p)) {
+ rc_update_bit_0(ctx, p);
+ *symbol *= 2;
+ return 0;
+ } else {
+ rc_update_bit_1(ctx, p);
+ *symbol = *symbol * 2 + 1;
+ return 1;
+ }
+}
+
+static int
+rc_direct_bit(struct unlzma_ctx *ctx)
+{
+ rc_normalize(ctx);
+ ctx->range >>= 1;
+ if (ctx->code >= ctx->range) {
+ ctx->code -= ctx->range;
+ return 1;
+ }
+ return 0;
+}
+
+static void
+rc_bit_tree_decode(struct unlzma_ctx *ctx, u16 *p, int num_levels, int *symbol)
+{
+ int i = num_levels;
+
+ *symbol = 1;
+ while (i--)
+ rc_get_bit(ctx, p + *symbol, symbol);
+ *symbol -= 1 << num_levels;
+}
+
+static u8
+peek_old_byte(struct unlzma_ctx *ctx, u32 offs)
+{
+ struct unlzma_buffer *bh = ctx->head;
+ u32 pos;
+
+ pos = ctx->pos - offs;
+ if (pos >= ctx->dict_size) {
+ pos = (~pos % ctx->dict_size);
+ }
+
+ while (bh->offset > pos) {
+ bh = bh->last;
+ if (!bh)
+ return 0;
+ }
+
+ pos -= bh->offset;
+ if (pos > bh->size)
+ return 0;
+
+ return bh->ptr[pos];
+}
+
+static void
+get_buffer(struct unlzma_ctx *ctx)
+{
+ struct unlzma_buffer *bh;
+
+ bh = kzalloc(sizeof(struct unlzma_buffer), GFP_KERNEL);
+ bh->ptr = ctx->next_out;
+ bh->offset = ctx->pos;
+ bh->last = ctx->head;
+ bh->size = ctx->avail_out;
+ ctx->head = bh;
+}
+
+static void
+write_byte(struct unlzma_ctx *ctx, u8 byte)
+{
+ if (unlikely(ctx->avail_out <= 0)) {
+ unlzma_request_buffer(ctx, &ctx->avail_out);
+ get_buffer(ctx);
+ }
+
+ if (!ctx->avail_out)
+ return;
+
+ ctx->previous_byte = byte;
+ *(ctx->next_out++) = byte;
+ ctx->avail_out--;
+ ctx->pos++;
+}
+
+
+static inline void
+copy_byte(struct unlzma_ctx *ctx, u32 offs)
+{
+ write_byte(ctx, peek_old_byte(ctx, offs));
+}
+
+static void
+copy_bytes(struct unlzma_ctx *ctx, u32 rep0, int len)
+{
+ do {
+ copy_byte(ctx, rep0);
+ len--;
+ if (unlzma_should_stop(ctx))
+ break;
+ } while (len != 0);
+}
+
+static void
+process_bit0(struct unlzma_ctx *ctx, u16 *p, int pos_state, u16 *prob,
+ int lc, u32 literal_pos_mask)
+{
+ int mi = 1;
+ rc_update_bit_0(ctx, prob);
+ prob = (p + LZMA_LITERAL +
+ (LZMA_LIT_SIZE
+ * (((ctx->pos & literal_pos_mask) << lc)
+ + (ctx->previous_byte >> (8 - lc))))
+ );
+
+ if (ctx->state >= LZMA_NUM_LIT_STATES) {
+ int match_byte = peek_old_byte(ctx, ctx->rep0);
+ do {
+ u16 bit;
+ u16 *prob_lit;
+
+ match_byte <<= 1;
+ bit = match_byte & 0x100;
+ prob_lit = prob + 0x100 + bit + mi;
+ if (rc_get_bit(ctx, prob_lit, &mi) != !!bit)
+ break;
+ } while (mi < 0x100);
+ }
+ while (mi < 0x100) {
+ u16 *prob_lit = prob + mi;
+ rc_get_bit(ctx, prob_lit, &mi);
+ }
+ write_byte(ctx, mi);
+ if (ctx->state < 4)
+ ctx->state = 0;
+ else if (ctx->state < 10)
+ ctx->state -= 3;
+ else
+ ctx->state -= 6;
+}
+
+static void
+process_bit1(struct unlzma_ctx *ctx, u16 *p, int pos_state, u16 *prob)
+{
+ int offset;
+ u16 *prob_len;
+ int num_bits;
+ int len;
+
+ rc_update_bit_1(ctx, prob);
+ prob = p + LZMA_IS_REP + ctx->state;
+ if (rc_is_bit_0(ctx, prob)) {
+ rc_update_bit_0(ctx, prob);
+ ctx->rep3 = ctx->rep2;
+ ctx->rep2 = ctx->rep1;
+ ctx->rep1 = ctx->rep0;
+ ctx->state = ctx->state < LZMA_NUM_LIT_STATES ? 0 : 3;
+ prob = p + LZMA_LEN_CODER;
+ } else {
+ rc_update_bit_1(ctx, prob);
+ prob = p + LZMA_IS_REP_G0 + ctx->state;
+ if (rc_is_bit_0(ctx, prob)) {
+ rc_update_bit_0(ctx, prob);
+ prob = (p + LZMA_IS_REP_0_LONG
+ + (ctx->state <<
+ LZMA_NUM_POS_BITS_MAX) +
+ pos_state);
+ if (rc_is_bit_0(ctx, prob)) {
+ rc_update_bit_0(ctx, prob);
+
+ ctx->state = ctx->state < LZMA_NUM_LIT_STATES ?
+ 9 : 11;
+ copy_byte(ctx, ctx->rep0);
+ return;
+ } else {
+ rc_update_bit_1(ctx, prob);
+ }
+ } else {
+ u32 distance;
+
+ rc_update_bit_1(ctx, prob);
+ prob = p + LZMA_IS_REP_G1 + ctx->state;
+ if (rc_is_bit_0(ctx, prob)) {
+ rc_update_bit_0(ctx, prob);
+ distance = ctx->rep1;
+ } else {
+ rc_update_bit_1(ctx, prob);
+ prob = p + LZMA_IS_REP_G2 + ctx->state;
+ if (rc_is_bit_0(ctx, prob)) {
+ rc_update_bit_0(ctx, prob);
+ distance = ctx->rep2;
+ } else {
+ rc_update_bit_1(ctx, prob);
+ distance = ctx->rep3;
+ ctx->rep3 = ctx->rep2;
+ }
+ ctx->rep2 = ctx->rep1;
+ }
+ ctx->rep1 = ctx->rep0;
+ ctx->rep0 = distance;
+ }
+ ctx->state = ctx->state < LZMA_NUM_LIT_STATES ? 8 : 11;
+ prob = p + LZMA_REP_LEN_CODER;
+ }
+
+ prob_len = prob + LZMA_LEN_CHOICE;
+ if (rc_is_bit_0(ctx, prob_len)) {
+ rc_update_bit_0(ctx, prob_len);
+ prob_len = (prob + LZMA_LEN_LOW
+ + (pos_state <<
+ LZMA_LEN_NUM_LOW_BITS));
+ offset = 0;
+ num_bits = LZMA_LEN_NUM_LOW_BITS;
+ } else {
+ rc_update_bit_1(ctx, prob_len);
+ prob_len = prob + LZMA_LEN_CHOICE_2;
+ if (rc_is_bit_0(ctx, prob_len)) {
+ rc_update_bit_0(ctx, prob_len);
+ prob_len = (prob + LZMA_LEN_MID
+ + (pos_state <<
+ LZMA_LEN_NUM_MID_BITS));
+ offset = 1 << LZMA_LEN_NUM_LOW_BITS;
+ num_bits = LZMA_LEN_NUM_MID_BITS;
+ } else {
+ rc_update_bit_1(ctx, prob_len);
+ prob_len = prob + LZMA_LEN_HIGH;
+ offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
+ + (1 << LZMA_LEN_NUM_MID_BITS));
+ num_bits = LZMA_LEN_NUM_HIGH_BITS;
+ }
+ }
+
+ rc_bit_tree_decode(ctx, prob_len, num_bits, &len);
+ len += offset;
+
+ if (ctx->state < 4) {
+ int pos_slot;
+
+ ctx->state += LZMA_NUM_LIT_STATES;
+ prob =
+ p + LZMA_POS_SLOT +
+ ((len <
+ LZMA_NUM_LEN_TO_POS_STATES ? len :
+ LZMA_NUM_LEN_TO_POS_STATES - 1)
+ << LZMA_NUM_POS_SLOT_BITS);
+ rc_bit_tree_decode(ctx, prob,
+ LZMA_NUM_POS_SLOT_BITS,
+ &pos_slot);
+ if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
+ int i, mi;
+ num_bits = (pos_slot >> 1) - 1;
+ ctx->rep0 = 2 | (pos_slot & 1);
+ if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
+ ctx->rep0 <<= num_bits;
+ prob = p + LZMA_SPEC_POS +
+ ctx->rep0 - pos_slot - 1;
+ } else {
+ num_bits -= LZMA_NUM_ALIGN_BITS;
+ while (num_bits--)
+ ctx->rep0 = (ctx->rep0 << 1) |
+ rc_direct_bit(ctx);
+ prob = p + LZMA_ALIGN;
+ ctx->rep0 <<= LZMA_NUM_ALIGN_BITS;
+ num_bits = LZMA_NUM_ALIGN_BITS;
+ }
+ i = 1;
+ mi = 1;
+ while (num_bits--) {
+ if (rc_get_bit(ctx, prob + mi, &mi))
+ ctx->rep0 |= i;
+ i <<= 1;
+ }
+ } else
+ ctx->rep0 = pos_slot;
+ if (++(ctx->rep0) == 0)
+ return;
+ }
+
+ len += LZMA_MATCH_MIN_LEN;
+
+ copy_bytes(ctx, ctx->rep0, len);
+}
+
+
+static int
+do_unlzma(struct unlzma_ctx *ctx)
+{
+ u8 hdr_buf[sizeof(struct lzma_header)];
+ struct lzma_header *header = (struct lzma_header *)hdr_buf;
+ u32 pos_state_mask;
+ u32 literal_pos_mask;
+ int lc, pb, lp;
+ int num_probs;
+ int i, mi;
+ u16 *p;
+
+ for (i = 0; i < sizeof(struct lzma_header); i++) {
+ hdr_buf[i] = rc_read(ctx);
+ }
+
+ ctx->pos = 0;
+ get_buffer(ctx);
+ ctx->active = true;
+ ctx->state = 0;
+ ctx->rep0 = ctx->rep1 = ctx->rep2 = ctx->rep3 = 1;
+
+ ctx->previous_byte = 0;
+ ctx->code = 0;
+ ctx->range = 0xFFFFFFFF;
+
+ ctx->dict_size = le32_to_cpu(header->dict_size);
+
+ if (header->pos >= (9 * 5 * 5))
+ return -1;
+
+ mi = 0;
+ lc = header->pos;
+ while (lc >= 9) {
+ mi++;
+ lc -= 9;
+ }
+ pb = 0;
+ lp = mi;
+ while (lp >= 5) {
+ pb++;
+ lp -= 5;
+ }
+ pos_state_mask = (1 << pb) - 1;
+ literal_pos_mask = (1 << lp) - 1;
+
+ if (ctx->dict_size == 0)
+ ctx->dict_size = 1;
+
+ num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
+ if (ctx->workspace_size < num_probs * sizeof(*p)) {
+ if (ctx->workspace)
+ vfree(ctx->workspace);
+ ctx->workspace = vmalloc(num_probs * sizeof(*p));
+ }
+ p = (u16 *) ctx->workspace;
+ if (!p)
+ return -1;
+
+ num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
+ for (i = 0; i < num_probs; i++)
+ p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
+
+ for (i = 0; i < 5; i++)
+ rc_get_code(ctx);
+
+ while (1) {
+ int pos_state = ctx->pos & pos_state_mask;
+ u16 *prob = p + LZMA_IS_MATCH +
+ (ctx->state << LZMA_NUM_POS_BITS_MAX) + pos_state;
+ if (rc_is_bit_0(ctx, prob))
+ process_bit0(ctx, p, pos_state, prob,
+ lc, literal_pos_mask);
+ else {
+ process_bit1(ctx, p, pos_state, prob);
+ if (ctx->rep0 == 0)
+ break;
+ }
+ if (unlzma_should_stop(ctx))
+ break;
+ }
+
+ return ctx->pos;
+}
+
+
+static void
+unlzma_reset_buf(struct unlzma_ctx *ctx)
+{
+ ctx->avail_in = 0;
+ ctx->next_in = NULL;
+ ctx->avail_out = 0;
+ ctx->next_out = NULL;
+}
+
+static int
+unlzma_thread(void *data)
+{
+ struct unlzma_ctx *ctx = data;
+
+ mutex_lock(&ctx->mutex);
+ do {
+ if (do_unlzma(ctx) < 0)
+ ctx->pos = 0;
+ unlzma_reset_buf(ctx);
+ ctx->cancel = false;
+ ctx->active = false;
+ while (ctx->head) {
+ struct unlzma_buffer *bh = ctx->head;
+ ctx->head = bh->last;
+ kfree(bh);
+ }
+ } while (!kthread_should_stop());
+ mutex_unlock(&ctx->mutex);
+ return 0;
+}
+
+
+static int
+unlzma_init(struct crypto_tfm *tfm)
+{
+ return 0;
+}
+
+static void
+unlzma_cancel(struct unlzma_ctx *ctx)
+{
+ unlzma_reset_buf(ctx);
+
+ if (!ctx->active)
+ return;
+
+ ctx->cancel = true;
+ do {
+ mutex_unlock(&ctx->mutex);
+ wake_up(&ctx->next_req);
+ schedule();
+ mutex_lock(&ctx->mutex);
+ } while (ctx->cancel);
+}
+
+
+static void
+unlzma_exit(struct crypto_tfm *tfm)
+{
+ struct unlzma_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ if (ctx->thread) {
+ unlzma_cancel(ctx);
+ kthread_stop(ctx->thread);
+ ctx->thread = NULL;
+ }
+}
+
+static int
+unlzma_decompress_setup(struct crypto_pcomp *tfm, void *p, unsigned int len)
+{
+ struct unlzma_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+ int ret = 0;
+
+ if (ctx->thread)
+ return 0;
+
+ mutex_init(&ctx->mutex);
+ init_waitqueue_head(&ctx->next_req);
+ ctx->thread = kthread_run(unlzma_thread, ctx, "unlzma/%d", instance++);
+ if (IS_ERR(ctx->thread)) {
+ ret = PTR_ERR(ctx->thread);
+ ctx->thread = NULL;
+ }
+
+ return ret;
+}
+
+static int
+unlzma_decompress_init(struct crypto_pcomp *tfm)
+{
+ struct unlzma_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+
+ ctx->pos = 0;
+ return 0;
+}
+
+static void
+unlzma_wait_complete(struct unlzma_ctx *ctx, bool finish)
+{
+ do {
+ mutex_unlock(&ctx->mutex);
+ wake_up(&ctx->next_req);
+ schedule();
+ mutex_lock(&ctx->mutex);
+ } while (ctx->active && (ctx->avail_in > 0) && (ctx->avail_out > 0));
+}
+
+static int
+unlzma_decompress_update(struct crypto_pcomp *tfm, struct comp_request *req)
+{
+ struct unlzma_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+ size_t pos = 0;
+
+ mutex_lock(&ctx->mutex);
+ if (!ctx->active && !req->avail_in)
+ goto out;
+
+ pos = ctx->pos;
+ ctx->next_in = req->next_in;
+ ctx->avail_in = req->avail_in;
+ ctx->next_out = req->next_out;
+ ctx->avail_out = req->avail_out;
+
+ unlzma_wait_complete(ctx, false);
+
+ req->next_in = ctx->next_in;
+ req->avail_in = ctx->avail_in;
+ req->next_out = ctx->next_out;
+ req->avail_out = ctx->avail_out;
+ pos = ctx->pos - pos;
+
+out:
+ mutex_unlock(&ctx->mutex);
+ return pos;
+}
+
+static int
+unlzma_decompress_final(struct crypto_pcomp *tfm, struct comp_request *req)
+{
+ struct unlzma_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+ int ret = 0;
+
+ /* cancel pending operation */
+ mutex_lock(&ctx->mutex);
+ if (ctx->active) {
+ // ret = -EINVAL;
+ unlzma_cancel(ctx);
+ }
+ ctx->pos = 0;
+ mutex_unlock(&ctx->mutex);
+ return ret;
+}
+
+
+static struct pcomp_alg unlzma_alg = {
+ .decompress_setup = unlzma_decompress_setup,
+ .decompress_init = unlzma_decompress_init,
+ .decompress_update = unlzma_decompress_update,
+ .decompress_final = unlzma_decompress_final,
+
+ .base = {
+ .cra_name = "lzma",
+ .cra_flags = CRYPTO_ALG_TYPE_PCOMPRESS,
+ .cra_ctxsize = sizeof(struct unlzma_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_init = unlzma_init,
+ .cra_exit = unlzma_exit,
+ }
+};
+
+static int __init
+unlzma_mod_init(void)
+{
+ return crypto_register_pcomp(&unlzma_alg);
+}
+
+static void __exit
+unlzma_mod_exit(void)
+{
+ crypto_unregister_pcomp(&unlzma_alg);
+}
+
+module_init(unlzma_mod_init);
+module_exit(unlzma_mod_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LZMA Decompression Algorithm");
+MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -758,6 +758,12 @@ config CRYPTO_ZLIB
help
This is the zlib algorithm.
+config CRYPTO_UNLZMA
+ tristate "LZMA decompression"
+ select CRYPTO_PCOMP
+ help
+ This is the lzma decompression module.
+
config CRYPTO_LZO
tristate "LZO compression algorithm"
select CRYPTO_ALGAPI
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -75,6 +75,7 @@ obj-$(CONFIG_CRYPTO_SEED) += seed.o
obj-$(CONFIG_CRYPTO_SALSA20) += salsa20_generic.o
obj-$(CONFIG_CRYPTO_DEFLATE) += deflate.o
obj-$(CONFIG_CRYPTO_ZLIB) += zlib.o
+obj-$(CONFIG_CRYPTO_UNLZMA) += unlzma.o
obj-$(CONFIG_CRYPTO_MICHAEL_MIC) += michael_mic.o
obj-$(CONFIG_CRYPTO_CRC32C) += crc32c.o
obj-$(CONFIG_CRYPTO_AUTHENC) += authenc.o
--- /dev/null
+++ b/crypto/unlzma.h
@@ -0,0 +1,80 @@
+/* LZMA uncompresion module for pcomp
+ * Copyright (C) 2009 Felix Fietkau <nbd@openwrt.org>
+ *
+ * Based on:
+ * Initial Linux kernel adaptation
+ * Copyright (C) 2006 Alain < alain@knaff.lu >
+ *
+ * Based on small lzma deflate implementation/Small range coder
+ * implementation for lzma.
+ * Copyright (C) 2006 Aurelien Jacobs < aurel@gnuage.org >
+ *
+ * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
+ * Copyright (C) 1999-2005 Igor Pavlov
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+#ifndef __UNLZMA_H
+#define __UNLZMA_H
+
+struct lzma_header {
+ __u8 pos;
+ __le32 dict_size;
+} __attribute__ ((packed)) ;
+
+
+#define RC_TOP_BITS 24
+#define RC_MOVE_BITS 5
+#define RC_MODEL_TOTAL_BITS 11
+
+#define LZMA_BASE_SIZE 1846
+#define LZMA_LIT_SIZE 768
+
+#define LZMA_NUM_POS_BITS_MAX 4
+
+#define LZMA_LEN_NUM_LOW_BITS 3
+#define LZMA_LEN_NUM_MID_BITS 3
+#define LZMA_LEN_NUM_HIGH_BITS 8
+
+#define LZMA_LEN_CHOICE 0
+#define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
+#define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
+#define LZMA_LEN_MID (LZMA_LEN_LOW \
+ + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
+#define LZMA_LEN_HIGH (LZMA_LEN_MID \
+ +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
+#define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
+
+#define LZMA_NUM_STATES 12
+#define LZMA_NUM_LIT_STATES 7
+
+#define LZMA_START_POS_MODEL_INDEX 4
+#define LZMA_END_POS_MODEL_INDEX 14
+#define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
+
+#define LZMA_NUM_POS_SLOT_BITS 6
+#define LZMA_NUM_LEN_TO_POS_STATES 4
+
+#define LZMA_NUM_ALIGN_BITS 4
+
+#define LZMA_MATCH_MIN_LEN 2
+
+#define LZMA_IS_MATCH 0
+#define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
+#define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
+#define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
+#define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
+#define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
+#define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
+ + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
+#define LZMA_SPEC_POS (LZMA_POS_SLOT \
+ +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
+#define LZMA_ALIGN (LZMA_SPEC_POS \
+ + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
+#define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
+#define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
+#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
+
+#endif