lib: Add zstd support to decompress
- Add unzstd() and the zstd decompress interface.
- Add zstd support to decompress_method().
The decompress_method() and unzstd() functions are used to decompress
the initramfs and the initrd. The __decompress() function is used in
the preboot environment to decompress a zstd compressed kernel.
The zstd decompression function allows the input and output buffers to
overlap because that is used by x86 kernel decompression.
Signed-off-by: Nick Terrell <terrelln@fb.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200730190841.2071656-3-nickrterrell@gmail.com
diff --git a/lib/Makefile b/lib/Makefile
index b1c42c1..2ba9642 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -170,6 +170,7 @@
lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
lib-$(CONFIG_DECOMPRESS_LZ4) += decompress_unlz4.o
+lib-$(CONFIG_DECOMPRESS_ZSTD) += decompress_unzstd.o
obj-$(CONFIG_TEXTSEARCH) += textsearch.o
obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o
