diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Makefile | 2 | ||||
-rw-r--r-- | lib/crypto/Makefile | 4 | ||||
-rw-r--r-- | lib/crypto/arc4.c | 74 | ||||
-rw-r--r-- | lib/scatterlist.c | 9 |
4 files changed, 84 insertions, 5 deletions
diff --git a/lib/Makefile b/lib/Makefile index fb7697031a79..d3daedf93c5a 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -102,7 +102,7 @@ endif obj-$(CONFIG_DEBUG_INFO_REDUCED) += debug_info.o CFLAGS_debug_info.o += $(call cc-option, -femit-struct-debug-detailed=any) -obj-y += math/ +obj-y += math/ crypto/ obj-$(CONFIG_GENERIC_IOMAP) += iomap.o obj-$(CONFIG_GENERIC_PCI_IOMAP) += pci_iomap.o diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile new file mode 100644 index 000000000000..88195c34932d --- /dev/null +++ b/lib/crypto/Makefile @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_CRYPTO_LIB_ARC4) += libarc4.o +libarc4-y := arc4.o diff --git a/lib/crypto/arc4.c b/lib/crypto/arc4.c new file mode 100644 index 000000000000..c2020f19c652 --- /dev/null +++ b/lib/crypto/arc4.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Cryptographic API + * + * ARC4 Cipher Algorithm + * + * Jon Oberheide <jon@oberheide.org> + */ + +#include <crypto/arc4.h> +#include <linux/module.h> + +int arc4_setkey(struct arc4_ctx *ctx, const u8 *in_key, unsigned int key_len) +{ + int i, j = 0, k = 0; + + ctx->x = 1; + ctx->y = 0; + + for (i = 0; i < 256; i++) + ctx->S[i] = i; + + for (i = 0; i < 256; i++) { + u32 a = ctx->S[i]; + + j = (j + in_key[k] + a) & 0xff; + ctx->S[i] = ctx->S[j]; + ctx->S[j] = a; + if (++k >= key_len) + k = 0; + } + + return 0; +} +EXPORT_SYMBOL(arc4_setkey); + +void arc4_crypt(struct arc4_ctx *ctx, u8 *out, const u8 *in, unsigned int len) +{ + u32 *const S = ctx->S; + u32 x, y, a, b; + u32 ty, ta, tb; + + if (len == 0) + return; + + x = ctx->x; + y = ctx->y; + + a = S[x]; + y = (y + a) & 0xff; + b = S[y]; + + do { + S[y] = a; + a = (a + b) & 0xff; + S[x] = b; + x = (x + 1) & 0xff; + ta = S[x]; + ty = (y + ta) & 0xff; + tb = S[ty]; + *out++ = *in++ ^ S[a]; + if (--len == 0) + break; + y = ty; + a = ta; + b = tb; + } while (true); + + ctx->x = x; + ctx->y = y; +} +EXPORT_SYMBOL(arc4_crypt); + +MODULE_LICENSE("GPL"); diff --git a/lib/scatterlist.c b/lib/scatterlist.c index 2882d9ba6607..eacb82468437 100644 --- a/lib/scatterlist.c +++ b/lib/scatterlist.c @@ -676,17 +676,18 @@ static bool sg_miter_get_next_page(struct sg_mapping_iter *miter) { if (!miter->__remaining) { struct scatterlist *sg; - unsigned long pgoffset; if (!__sg_page_iter_next(&miter->piter)) return false; sg = miter->piter.sg; - pgoffset = miter->piter.sg_pgoffset; - miter->__offset = pgoffset ? 0 : sg->offset; + miter->__offset = miter->piter.sg_pgoffset ? 0 : sg->offset; + miter->piter.sg_pgoffset += miter->__offset >> PAGE_SHIFT; + miter->__offset &= PAGE_SIZE - 1; miter->__remaining = sg->offset + sg->length - - (pgoffset << PAGE_SHIFT) - miter->__offset; + (miter->piter.sg_pgoffset << PAGE_SHIFT) - + miter->__offset; miter->__remaining = min_t(unsigned long, miter->__remaining, PAGE_SIZE - miter->__offset); } |