[thirdparty/linux.git] / lib / decompress_unlz4.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Wrapper for decompressing LZ4-compressed kernel, initramfs, and initrd
 *
 * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
 */

#ifdef STATIC
#define PREBOOT
#include "lz4/lz4_decompress.c"
#else
#include <linux/decompress/unlz4.h>
#endif
#include <linux/types.h>
#include <linux/lz4.h>
#include <linux/decompress/mm.h>
#include <linux/compiler.h>

#include <asm/unaligned.h>

/*
 * Note: Uncompressed chunk size is used in the compressor side
 * (userspace side for compression).
 * It is hardcoded because there is not proper way to extract it
 * from the binary stream which is generated by the preliminary
 * version of LZ4 tool so far.
 */
#define LZ4_DEFAULT_UNCOMPRESSED_CHUNK_SIZE (8 << 20)
#define ARCHIVE_MAGICNUMBER 0x184C2102

STATIC inline int INIT unlz4(u8 *input, long in_len,
				long (*fill)(void *, unsigned long),
				long (*flush)(void *, unsigned long),
				u8 *output, long *posp,
				void (*error) (char *x))
{
	int ret = -1;
	size_t chunksize = 0;
	size_t uncomp_chunksize = LZ4_DEFAULT_UNCOMPRESSED_CHUNK_SIZE;
	u8 *inp;
	u8 *inp_start;
	u8 *outp;
	long size = in_len;
#ifdef PREBOOT
	size_t out_len = get_unaligned_le32(input + in_len);
#endif
	size_t dest_len;


	if (output) {
		outp = output;
	} else if (!flush) {
		error("NULL output pointer and no flush function provided");
		goto exit_0;
	} else {
		outp = large_malloc(uncomp_chunksize);
		if (!outp) {
			error("Could not allocate output buffer");
			goto exit_0;
		}
	}

	if (input && fill) {
		error("Both input pointer and fill function provided,");
		goto exit_1;
	} else if (input) {
		inp = input;
	} else if (!fill) {
		error("NULL input pointer and missing fill function");
		goto exit_1;
	} else {
		inp = large_malloc(LZ4_compressBound(uncomp_chunksize));
		if (!inp) {
			error("Could not allocate input buffer");
			goto exit_1;
		}
	}
	inp_start = inp;

	if (posp)
		*posp = 0;

	if (fill) {
		size = fill(inp, 4);
		if (size < 4) {
			error("data corrupted");
			goto exit_2;
		}
	}

	chunksize = get_unaligned_le32(inp);
	if (chunksize == ARCHIVE_MAGICNUMBER) {
		if (!fill) {
			inp += 4;
			size -= 4;
		}
	} else {
		error("invalid header");
		goto exit_2;
	}

	if (posp)
		*posp += 4;

	for (;;) {

		if (fill) {
			size = fill(inp, 4);
			if (size == 0)
				break;
			if (size < 4) {
				error("data corrupted");
				goto exit_2;
			}
		} else if (size < 4) {
			/* empty or end-of-file */
			goto exit_3;
		}

		chunksize = get_unaligned_le32(inp);
		if (chunksize == ARCHIVE_MAGICNUMBER) {
			if (!fill) {
				inp += 4;
				size -= 4;
			}
			if (posp)
				*posp += 4;
			continue;
		}

		if (!fill && chunksize == 0) {
			/* empty or end-of-file */
			goto exit_3;
		}

		if (posp)
			*posp += 4;

		if (!fill) {
			inp += 4;
			size -= 4;
		} else {
			if (chunksize > LZ4_compressBound(uncomp_chunksize)) {
				error("chunk length is longer than allocated");
				goto exit_2;
			}
			size = fill(inp, chunksize);
			if (size < chunksize) {
				error("data corrupted");
				goto exit_2;
			}
		}
#ifdef PREBOOT
		if (out_len >= uncomp_chunksize) {
			dest_len = uncomp_chunksize;
			out_len -= dest_len;
		} else
			dest_len = out_len;

		ret = LZ4_decompress_fast(inp, outp, dest_len);
		chunksize = ret;
#else
		dest_len = uncomp_chunksize;

		ret = LZ4_decompress_safe(inp, outp, chunksize, dest_len);
		dest_len = ret;
#endif
		if (ret < 0) {
			error("Decoding failed");
			goto exit_2;
		}

		ret = -1;
		if (flush && flush(outp, dest_len) != dest_len)
			goto exit_2;
		if (output)
			outp += dest_len;
		if (posp)
			*posp += chunksize;

		if (!fill) {
			size -= chunksize;

			if (size == 0)
				break;
			else if (size < 0) {
				error("data corrupted");
				goto exit_2;
			}
			inp += chunksize;
		}
	}

exit_3:
	ret = 0;
exit_2:
	if (!input)
		large_free(inp_start);
exit_1:
	if (!output)
		large_free(outp);
exit_0:
	return ret;
}

#ifdef PREBOOT
STATIC int INIT __decompress(unsigned char *buf, long in_len,
			      long (*fill)(void*, unsigned long),
			      long (*flush)(void*, unsigned long),
			      unsigned char *output, long out_len,
			      long *posp,
			      void (*error)(char *x)
	)
{
	return unlz4(buf, in_len - 4, fill, flush, output, posp, error);
}
#endif
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
e76e1fdf KL	2	/*
	3	* Wrapper for decompressing LZ4-compressed kernel, initramfs, and initrd
	4	*
	5	* Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
e76e1fdf KL	6	*/
	7
	8	#ifdef STATIC
	9	#define PREBOOT
	10	#include "lz4/lz4_decompress.c"
	11	#else
	12	#include <linux/decompress/unlz4.h>
	13	#endif
	14	#include <linux/types.h>
	15	#include <linux/lz4.h>
	16	#include <linux/decompress/mm.h>
	17	#include <linux/compiler.h>
	18
	19	#include <asm/unaligned.h>
	20
	21	/*
	22	* Note: Uncompressed chunk size is used in the compressor side
	23	* (userspace side for compression).
	24	* It is hardcoded because there is not proper way to extract it
	25	* from the binary stream which is generated by the preliminary
	26	* version of LZ4 tool so far.
	27	*/
	28	#define LZ4_DEFAULT_UNCOMPRESSED_CHUNK_SIZE (8 << 20)
	29	#define ARCHIVE_MAGICNUMBER 0x184C2102
	30
d97b07c5 YL	31	STATIC inline int INIT unlz4(u8 *input, long in_len,
	32	long (fill)(void , unsigned long),
	33	long (flush)(void , unsigned long),
	34	u8 output, long posp,
e76e1fdf KL	35	void (error) (char x))
	36	{
	37	int ret = -1;
	38	size_t chunksize = 0;
	39	size_t uncomp_chunksize = LZ4_DEFAULT_UNCOMPRESSED_CHUNK_SIZE;
	40	u8 *inp;
	41	u8 *inp_start;
	42	u8 *outp;
d97b07c5	43	long size = in_len;
e76e1fdf KL	44	#ifdef PREBOOT
	45	size_t out_len = get_unaligned_le32(input + in_len);
	46	#endif
	47	size_t dest_len;
	48
	49
	50	if (output) {
	51	outp = output;
	52	} else if (!flush) {
	53	error("NULL output pointer and no flush function provided");
	54	goto exit_0;
	55	} else {
	56	outp = large_malloc(uncomp_chunksize);
	57	if (!outp) {
	58	error("Could not allocate output buffer");
	59	goto exit_0;
	60	}
	61	}
	62
	63	if (input && fill) {
	64	error("Both input pointer and fill function provided,");
	65	goto exit_1;
	66	} else if (input) {
	67	inp = input;
	68	} else if (!fill) {
	69	error("NULL input pointer and missing fill function");
	70	goto exit_1;
	71	} else {
e23d54e4	72	inp = large_malloc(LZ4_compressBound(uncomp_chunksize));
e76e1fdf KL	73	if (!inp) {
	74	error("Could not allocate input buffer");
	75	goto exit_1;
	76	}
	77	}
	78	inp_start = inp;
	79
	80	if (posp)
	81	*posp = 0;
	82
4d4b866a YL	83	if (fill) {
	84	size = fill(inp, 4);
	85	if (size < 4) {
	86	error("data corrupted");
	87	goto exit_2;
	88	}
	89	}
e76e1fdf KL	90
	91	chunksize = get_unaligned_le32(inp);
	92	if (chunksize == ARCHIVE_MAGICNUMBER) {
4d4b866a YL	93	if (!fill) {
	94	inp += 4;
	95	size -= 4;
	96	}
e76e1fdf KL	97	} else {
	98	error("invalid header");
	99	goto exit_2;
	100	}
	101
	102	if (posp)
	103	*posp += 4;
	104
	105	for (;;) {
	106
4d4b866a YL	107	if (fill) {
	108	size = fill(inp, 4);
	109	if (size == 0)
	110	break;
	111	if (size < 4) {
	112	error("data corrupted");
	113	goto exit_2;
	114	}
2c484419 DJL	115	} else if (size < 4) {
	116	/* empty or end-of-file */
	117	goto exit_3;
4d4b866a	118	}
e76e1fdf KL	119
	120	chunksize = get_unaligned_le32(inp);
	121	if (chunksize == ARCHIVE_MAGICNUMBER) {
4d4b866a YL	122	if (!fill) {
	123	inp += 4;
	124	size -= 4;
	125	}
e76e1fdf KL	126	if (posp)
	127	*posp += 4;
	128	continue;
	129	}
4d4b866a	130
2c484419 DJL	131	if (!fill && chunksize == 0) {
	132	/* empty or end-of-file */
	133	goto exit_3;
	134	}
e76e1fdf KL	135
	136	if (posp)
	137	*posp += 4;
	138
4d4b866a YL	139	if (!fill) {
	140	inp += 4;
	141	size -= 4;
	142	} else {
e23d54e4	143	if (chunksize > LZ4_compressBound(uncomp_chunksize)) {
e76e1fdf KL	144	error("chunk length is longer than allocated");
	145	goto exit_2;
	146	}
4d4b866a YL	147	size = fill(inp, chunksize);
	148	if (size < chunksize) {
	149	error("data corrupted");
	150	goto exit_2;
	151	}
e76e1fdf KL	152	}
	153	#ifdef PREBOOT
	154	if (out_len >= uncomp_chunksize) {
	155	dest_len = uncomp_chunksize;
	156	out_len -= dest_len;
	157	} else
	158	dest_len = out_len;
e23d54e4 SS	159
	160	ret = LZ4_decompress_fast(inp, outp, dest_len);
	161	chunksize = ret;
e76e1fdf KL	162	#else
e76e1fdf KL	163	dest_len = uncomp_chunksize;
e23d54e4 SS	164
	165	ret = LZ4_decompress_safe(inp, outp, chunksize, dest_len);
	166	dest_len = ret;
e76e1fdf KL	167	#endif
	168	if (ret < 0) {
	169	error("Decoding failed");
	170	goto exit_2;
	171	}
	172
2a1d689c	173	ret = -1;
e76e1fdf KL	174	if (flush && flush(outp, dest_len) != dest_len)
	175	goto exit_2;
	176	if (output)
	177	outp += dest_len;
	178	if (posp)
	179	*posp += chunksize;
	180
4d4b866a YL	181	if (!fill) {
4d4b866a YL	182	size -= chunksize;
e76e1fdf	183
4d4b866a YL	184	if (size == 0)
	185	break;
	186	else if (size < 0) {
	187	error("data corrupted");
	188	goto exit_2;
	189	}
	190	inp += chunksize;
e76e1fdf	191	}
e76e1fdf KL	192	}
e76e1fdf KL	193
2c484419	194	exit_3:
e76e1fdf KL	195	ret = 0;
	196	exit_2:
	197	if (!input)
	198	large_free(inp_start);
	199	exit_1:
	200	if (!output)
	201	large_free(outp);
	202	exit_0:
	203	return ret;
	204	}
	205
	206	#ifdef PREBOOT
2d3862d2	207	STATIC int INIT __decompress(unsigned char *buf, long in_len,
d97b07c5 YL	208	long (fill)(void, unsigned long),
d97b07c5 YL	209	long (flush)(void, unsigned long),
2d3862d2	210	unsigned char *output, long out_len,
d97b07c5	211	long *posp,
2d3862d2	212	void (error)(char x)
e76e1fdf KL	213	)
	214	{
	215	return unlz4(buf, in_len - 4, fill, flush, output, posp, error);
	216	}
	217	#endif