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-rw-r--r--lib/crypto/sha256.c209
1 files changed, 209 insertions, 0 deletions
diff --git a/lib/crypto/sha256.c b/lib/crypto/sha256.c
new file mode 100644
index 000000000..72a4b0b1d
--- /dev/null
+++ b/lib/crypto/sha256.c
@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * SHA-256, as specified in
+ * http://csrc.nist.gov/groups/STM/cavp/documents/shs/sha256-384-512.pdf
+ *
+ * SHA-256 code by Jean-Luc Cooke <jlcooke@certainkey.com>.
+ *
+ * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
+ * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ * Copyright (c) 2014 Red Hat Inc.
+ */
+
+#include <linux/bitops.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <crypto/sha2.h>
+#include <asm/unaligned.h>
+
+static const u32 SHA256_K[] = {
+ 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
+ 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
+ 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
+ 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
+ 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
+ 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
+ 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
+ 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
+ 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
+ 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+ 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
+ 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
+ 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
+ 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
+ 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
+ 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
+};
+
+static inline u32 Ch(u32 x, u32 y, u32 z)
+{
+ return z ^ (x & (y ^ z));
+}
+
+static inline u32 Maj(u32 x, u32 y, u32 z)
+{
+ return (x & y) | (z & (x | y));
+}
+
+#define e0(x) (ror32(x, 2) ^ ror32(x, 13) ^ ror32(x, 22))
+#define e1(x) (ror32(x, 6) ^ ror32(x, 11) ^ ror32(x, 25))
+#define s0(x) (ror32(x, 7) ^ ror32(x, 18) ^ (x >> 3))
+#define s1(x) (ror32(x, 17) ^ ror32(x, 19) ^ (x >> 10))
+
+static inline void LOAD_OP(int I, u32 *W, const u8 *input)
+{
+ W[I] = get_unaligned_be32((__u32 *)input + I);
+}
+
+static inline void BLEND_OP(int I, u32 *W)
+{
+ W[I] = s1(W[I-2]) + W[I-7] + s0(W[I-15]) + W[I-16];
+}
+
+#define SHA256_ROUND(i, a, b, c, d, e, f, g, h) do { \
+ u32 t1, t2; \
+ t1 = h + e1(e) + Ch(e, f, g) + SHA256_K[i] + W[i]; \
+ t2 = e0(a) + Maj(a, b, c); \
+ d += t1; \
+ h = t1 + t2; \
+} while (0)
+
+static void sha256_transform(u32 *state, const u8 *input, u32 *W)
+{
+ u32 a, b, c, d, e, f, g, h;
+ int i;
+
+ /* load the input */
+ for (i = 0; i < 16; i += 8) {
+ LOAD_OP(i + 0, W, input);
+ LOAD_OP(i + 1, W, input);
+ LOAD_OP(i + 2, W, input);
+ LOAD_OP(i + 3, W, input);
+ LOAD_OP(i + 4, W, input);
+ LOAD_OP(i + 5, W, input);
+ LOAD_OP(i + 6, W, input);
+ LOAD_OP(i + 7, W, input);
+ }
+
+ /* now blend */
+ for (i = 16; i < 64; i += 8) {
+ BLEND_OP(i + 0, W);
+ BLEND_OP(i + 1, W);
+ BLEND_OP(i + 2, W);
+ BLEND_OP(i + 3, W);
+ BLEND_OP(i + 4, W);
+ BLEND_OP(i + 5, W);
+ BLEND_OP(i + 6, W);
+ BLEND_OP(i + 7, W);
+ }
+
+ /* load the state into our registers */
+ a = state[0]; b = state[1]; c = state[2]; d = state[3];
+ e = state[4]; f = state[5]; g = state[6]; h = state[7];
+
+ /* now iterate */
+ for (i = 0; i < 64; i += 8) {
+ SHA256_ROUND(i + 0, a, b, c, d, e, f, g, h);
+ SHA256_ROUND(i + 1, h, a, b, c, d, e, f, g);
+ SHA256_ROUND(i + 2, g, h, a, b, c, d, e, f);
+ SHA256_ROUND(i + 3, f, g, h, a, b, c, d, e);
+ SHA256_ROUND(i + 4, e, f, g, h, a, b, c, d);
+ SHA256_ROUND(i + 5, d, e, f, g, h, a, b, c);
+ SHA256_ROUND(i + 6, c, d, e, f, g, h, a, b);
+ SHA256_ROUND(i + 7, b, c, d, e, f, g, h, a);
+ }
+
+ state[0] += a; state[1] += b; state[2] += c; state[3] += d;
+ state[4] += e; state[5] += f; state[6] += g; state[7] += h;
+}
+
+void sha256_update(struct sha256_state *sctx, const u8 *data, unsigned int len)
+{
+ unsigned int partial, done;
+ const u8 *src;
+ u32 W[64];
+
+ partial = sctx->count & 0x3f;
+ sctx->count += len;
+ done = 0;
+ src = data;
+
+ if ((partial + len) > 63) {
+ if (partial) {
+ done = -partial;
+ memcpy(sctx->buf + partial, data, done + 64);
+ src = sctx->buf;
+ }
+
+ do {
+ sha256_transform(sctx->state, src, W);
+ done += 64;
+ src = data + done;
+ } while (done + 63 < len);
+
+ memzero_explicit(W, sizeof(W));
+
+ partial = 0;
+ }
+ memcpy(sctx->buf + partial, src, len - done);
+}
+EXPORT_SYMBOL(sha256_update);
+
+void sha224_update(struct sha256_state *sctx, const u8 *data, unsigned int len)
+{
+ sha256_update(sctx, data, len);
+}
+EXPORT_SYMBOL(sha224_update);
+
+static void __sha256_final(struct sha256_state *sctx, u8 *out, int digest_words)
+{
+ __be32 *dst = (__be32 *)out;
+ __be64 bits;
+ unsigned int index, pad_len;
+ int i;
+ static const u8 padding[64] = { 0x80, };
+
+ /* Save number of bits */
+ bits = cpu_to_be64(sctx->count << 3);
+
+ /* Pad out to 56 mod 64. */
+ index = sctx->count & 0x3f;
+ pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
+ sha256_update(sctx, padding, pad_len);
+
+ /* Append length (before padding) */
+ sha256_update(sctx, (const u8 *)&bits, sizeof(bits));
+
+ /* Store state in digest */
+ for (i = 0; i < digest_words; i++)
+ put_unaligned_be32(sctx->state[i], &dst[i]);
+
+ /* Zeroize sensitive information. */
+ memzero_explicit(sctx, sizeof(*sctx));
+}
+
+void sha256_final(struct sha256_state *sctx, u8 *out)
+{
+ __sha256_final(sctx, out, 8);
+}
+EXPORT_SYMBOL(sha256_final);
+
+void sha224_final(struct sha256_state *sctx, u8 *out)
+{
+ __sha256_final(sctx, out, 7);
+}
+EXPORT_SYMBOL(sha224_final);
+
+void sha256(const u8 *data, unsigned int len, u8 *out)
+{
+ struct sha256_state sctx;
+
+ sha256_init(&sctx);
+ sha256_update(&sctx, data, len);
+ sha256_final(&sctx, out);
+}
+EXPORT_SYMBOL(sha256);
+
+MODULE_LICENSE("GPL");