| /* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0-only */ |
| |
| #include <commonlib/bsd/compression.h> |
| #include <commonlib/bsd/helpers.h> |
| #include <commonlib/bsd/sysincludes.h> |
| #include <stdint.h> |
| #include <string.h> |
| |
| /* LZ4 comes with its own supposedly portable memory access functions, but they |
| * seem to be very inefficient in practice (at least on ARM64). Since coreboot |
| * knows about endinaness and allows some basic assumptions (such as unaligned |
| * access support), we can easily write the ones we need ourselves. */ |
| static uint16_t LZ4_readLE16(const void *src) |
| { |
| return le16toh(*(const uint16_t *)src); |
| } |
| static void LZ4_copy8(void *dst, const void *src) |
| { |
| /* ARM32 needs to be a special snowflake to prevent GCC from coalescing the |
| * access into LDRD/STRD (which don't support unaligned accesses). */ |
| #ifdef __arm__ /* ARMv < 6 doesn't support unaligned accesses at all. */ |
| #if defined(__COREBOOT_ARM_ARCH__) && __COREBOOT_ARM_ARCH__ < 6 |
| int i; |
| for (i = 0; i < 8; i++) |
| ((uint8_t *)dst)[i] = ((uint8_t *)src)[i]; |
| #else |
| uint32_t x0, x1; |
| __asm__ ("ldr %[x0], [%[src]]" |
| : [x0]"=r"(x0) |
| : [src]"r"(src), "m"(*(const uint32_t *)src)); |
| __asm__ ("ldr %[x1], [%[src], #4]" |
| : [x1]"=r"(x1) |
| : [src]"r"(src), "m"(*(const uint32_t *)(src + 4))); |
| __asm__ ("str %[x0], [%[dst]]" |
| : "=m"(*(uint32_t *)dst) |
| : [x0]"r"(x0), [dst]"r"(dst)); |
| __asm__ ("str %[x1], [%[dst], #4]" |
| : "=m"(*(uint32_t *)(dst + 4)) |
| : [x1]"r"(x1), [dst]"r"(dst)); |
| #endif |
| #elif defined(__riscv) |
| /* RISC-V implementations may trap on any unaligned access. */ |
| int i; |
| for (i = 0; i < 8; i++) |
| ((uint8_t *)dst)[i] = ((uint8_t *)src)[i]; |
| #else |
| *(uint64_t *)dst = *(const uint64_t *)src; |
| #endif |
| } |
| |
| typedef uint8_t BYTE; |
| typedef uint16_t U16; |
| typedef uint32_t U32; |
| typedef int32_t S32; |
| typedef uint64_t U64; |
| |
| #define FORCE_INLINE static __always_inline |
| #define likely(expr) __builtin_expect((expr) != 0, 1) |
| #define unlikely(expr) __builtin_expect((expr) != 0, 0) |
| |
| /* Unaltered (just removed unrelated code) from github.com/Cyan4973/lz4/dev. */ |
| #include "lz4.c.inc" /* #include for inlining, do not link! */ |
| |
| #define LZ4F_MAGICNUMBER 0x184D2204 |
| |
| struct lz4_frame_header { |
| uint32_t magic; |
| union { |
| uint8_t flags; |
| struct { |
| uint8_t reserved0 : 2; |
| uint8_t has_content_checksum : 1; |
| uint8_t has_content_size : 1; |
| uint8_t has_block_checksum : 1; |
| uint8_t independent_blocks : 1; |
| uint8_t version : 2; |
| }; |
| }; |
| union { |
| uint8_t block_descriptor; |
| struct { |
| uint8_t reserved1 : 4; |
| uint8_t max_block_size : 3; |
| uint8_t reserved2 : 1; |
| }; |
| }; |
| /* + uint64_t content_size iff has_content_size is set */ |
| /* + uint8_t header_checksum */ |
| } __packed; |
| |
| struct lz4_block_header { |
| union { |
| uint32_t raw; |
| struct { |
| uint32_t size : 31; |
| uint32_t not_compressed : 1; |
| }; |
| }; |
| /* + size bytes of data */ |
| /* + uint32_t block_checksum iff has_block_checksum is set */ |
| } __packed; |
| |
| size_t ulz4fn(const void *src, size_t srcn, void *dst, size_t dstn) |
| { |
| const void *in = src; |
| void *out = dst; |
| size_t out_size = 0; |
| int has_block_checksum; |
| |
| { /* With in-place decompression the header may become invalid later. */ |
| const struct lz4_frame_header *h = in; |
| |
| if (srcn < sizeof(*h) + sizeof(uint64_t) + sizeof(uint8_t)) |
| return 0; /* input overrun */ |
| |
| /* We assume there's always only a single, standard frame. */ |
| if (le32toh(h->magic) != LZ4F_MAGICNUMBER || h->version != 1) |
| return 0; /* unknown format */ |
| if (h->reserved0 || h->reserved1 || h->reserved2) |
| return 0; /* reserved must be zero */ |
| if (!h->independent_blocks) |
| return 0; /* we don't support block dependency */ |
| has_block_checksum = h->has_block_checksum; |
| |
| in += sizeof(*h); |
| if (h->has_content_size) |
| in += sizeof(uint64_t); |
| in += sizeof(uint8_t); |
| } |
| |
| while (1) { |
| if ((size_t)(in - src) + sizeof(struct lz4_block_header) > srcn) |
| break; /* input overrun */ |
| |
| struct lz4_block_header b = { |
| { .raw = le32toh(*(const uint32_t *)in) } |
| }; |
| in += sizeof(struct lz4_block_header); |
| |
| if ((size_t)(in - src) + b.size > srcn) |
| break; /* input overrun */ |
| |
| if (!b.size) { |
| out_size = out - dst; |
| break; /* decompression successful */ |
| } |
| |
| if (b.not_compressed) { |
| size_t size = MIN((uintptr_t)b.size, (uintptr_t)dst |
| + dstn - (uintptr_t)out); |
| memcpy(out, in, size); |
| if (size < b.size) |
| break; /* output overrun */ |
| out += size; |
| } else { |
| /* constant folding essential, do not touch params! */ |
| int ret = LZ4_decompress_generic(in, out, b.size, |
| dst + dstn - out, endOnInputSize, |
| full, 0, noDict, out, NULL, 0); |
| if (ret < 0) |
| break; /* decompression error */ |
| out += ret; |
| } |
| |
| in += b.size; |
| if (has_block_checksum) |
| in += sizeof(uint32_t); |
| } |
| |
| return out_size; |
| } |
| |
| size_t ulz4f(const void *src, void *dst) |
| { |
| /* LZ4 uses signed size parameters, so can't just use ((u32)-1) here. */ |
| return ulz4fn(src, 1*GiB, dst, 1*GiB); |
| } |