Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/lib/crypto/chacha20poly1305.c b/lib/crypto/chacha20poly1305.c
new file mode 100644
index 0000000..5850f3b
--- /dev/null
+++ b/lib/crypto/chacha20poly1305.c
@@ -0,0 +1,368 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ *
+ * This is an implementation of the ChaCha20Poly1305 AEAD construction.
+ *
+ * Information: https://tools.ietf.org/html/rfc8439
+ */
+
+#include <crypto/algapi.h>
+#include <crypto/chacha20poly1305.h>
+#include <crypto/chacha.h>
+#include <crypto/poly1305.h>
+#include <crypto/scatterwalk.h>
+
+#include <asm/unaligned.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+
+#define CHACHA_KEY_WORDS	(CHACHA_KEY_SIZE / sizeof(u32))
+
+static void chacha_load_key(u32 *k, const u8 *in)
+{
+	k[0] = get_unaligned_le32(in);
+	k[1] = get_unaligned_le32(in + 4);
+	k[2] = get_unaligned_le32(in + 8);
+	k[3] = get_unaligned_le32(in + 12);
+	k[4] = get_unaligned_le32(in + 16);
+	k[5] = get_unaligned_le32(in + 20);
+	k[6] = get_unaligned_le32(in + 24);
+	k[7] = get_unaligned_le32(in + 28);
+}
+
+static void xchacha_init(u32 *chacha_state, const u8 *key, const u8 *nonce)
+{
+	u32 k[CHACHA_KEY_WORDS];
+	u8 iv[CHACHA_IV_SIZE];
+
+	memset(iv, 0, 8);
+	memcpy(iv + 8, nonce + 16, 8);
+
+	chacha_load_key(k, key);
+
+	/* Compute the subkey given the original key and first 128 nonce bits */
+	chacha_init(chacha_state, k, nonce);
+	hchacha_block(chacha_state, k, 20);
+
+	chacha_init(chacha_state, k, iv);
+
+	memzero_explicit(k, sizeof(k));
+	memzero_explicit(iv, sizeof(iv));
+}
+
+static void
+__chacha20poly1305_encrypt(u8 *dst, const u8 *src, const size_t src_len,
+			   const u8 *ad, const size_t ad_len, u32 *chacha_state)
+{
+	const u8 *pad0 = page_address(ZERO_PAGE(0));
+	struct poly1305_desc_ctx poly1305_state;
+	union {
+		u8 block0[POLY1305_KEY_SIZE];
+		__le64 lens[2];
+	} b;
+
+	chacha20_crypt(chacha_state, b.block0, pad0, sizeof(b.block0));
+	poly1305_init(&poly1305_state, b.block0);
+
+	poly1305_update(&poly1305_state, ad, ad_len);
+	if (ad_len & 0xf)
+		poly1305_update(&poly1305_state, pad0, 0x10 - (ad_len & 0xf));
+
+	chacha20_crypt(chacha_state, dst, src, src_len);
+
+	poly1305_update(&poly1305_state, dst, src_len);
+	if (src_len & 0xf)
+		poly1305_update(&poly1305_state, pad0, 0x10 - (src_len & 0xf));
+
+	b.lens[0] = cpu_to_le64(ad_len);
+	b.lens[1] = cpu_to_le64(src_len);
+	poly1305_update(&poly1305_state, (u8 *)b.lens, sizeof(b.lens));
+
+	poly1305_final(&poly1305_state, dst + src_len);
+
+	memzero_explicit(chacha_state, CHACHA_STATE_WORDS * sizeof(u32));
+	memzero_explicit(&b, sizeof(b));
+}
+
+void chacha20poly1305_encrypt(u8 *dst, const u8 *src, const size_t src_len,
+			      const u8 *ad, const size_t ad_len,
+			      const u64 nonce,
+			      const u8 key[CHACHA20POLY1305_KEY_SIZE])
+{
+	u32 chacha_state[CHACHA_STATE_WORDS];
+	u32 k[CHACHA_KEY_WORDS];
+	__le64 iv[2];
+
+	chacha_load_key(k, key);
+
+	iv[0] = 0;
+	iv[1] = cpu_to_le64(nonce);
+
+	chacha_init(chacha_state, k, (u8 *)iv);
+	__chacha20poly1305_encrypt(dst, src, src_len, ad, ad_len, chacha_state);
+
+	memzero_explicit(iv, sizeof(iv));
+	memzero_explicit(k, sizeof(k));
+}
+EXPORT_SYMBOL(chacha20poly1305_encrypt);
+
+void xchacha20poly1305_encrypt(u8 *dst, const u8 *src, const size_t src_len,
+			       const u8 *ad, const size_t ad_len,
+			       const u8 nonce[XCHACHA20POLY1305_NONCE_SIZE],
+			       const u8 key[CHACHA20POLY1305_KEY_SIZE])
+{
+	u32 chacha_state[CHACHA_STATE_WORDS];
+
+	xchacha_init(chacha_state, key, nonce);
+	__chacha20poly1305_encrypt(dst, src, src_len, ad, ad_len, chacha_state);
+}
+EXPORT_SYMBOL(xchacha20poly1305_encrypt);
+
+static bool
+__chacha20poly1305_decrypt(u8 *dst, const u8 *src, const size_t src_len,
+			   const u8 *ad, const size_t ad_len, u32 *chacha_state)
+{
+	const u8 *pad0 = page_address(ZERO_PAGE(0));
+	struct poly1305_desc_ctx poly1305_state;
+	size_t dst_len;
+	int ret;
+	union {
+		u8 block0[POLY1305_KEY_SIZE];
+		u8 mac[POLY1305_DIGEST_SIZE];
+		__le64 lens[2];
+	} b;
+
+	if (unlikely(src_len < POLY1305_DIGEST_SIZE))
+		return false;
+
+	chacha20_crypt(chacha_state, b.block0, pad0, sizeof(b.block0));
+	poly1305_init(&poly1305_state, b.block0);
+
+	poly1305_update(&poly1305_state, ad, ad_len);
+	if (ad_len & 0xf)
+		poly1305_update(&poly1305_state, pad0, 0x10 - (ad_len & 0xf));
+
+	dst_len = src_len - POLY1305_DIGEST_SIZE;
+	poly1305_update(&poly1305_state, src, dst_len);
+	if (dst_len & 0xf)
+		poly1305_update(&poly1305_state, pad0, 0x10 - (dst_len & 0xf));
+
+	b.lens[0] = cpu_to_le64(ad_len);
+	b.lens[1] = cpu_to_le64(dst_len);
+	poly1305_update(&poly1305_state, (u8 *)b.lens, sizeof(b.lens));
+
+	poly1305_final(&poly1305_state, b.mac);
+
+	ret = crypto_memneq(b.mac, src + dst_len, POLY1305_DIGEST_SIZE);
+	if (likely(!ret))
+		chacha20_crypt(chacha_state, dst, src, dst_len);
+
+	memzero_explicit(&b, sizeof(b));
+
+	return !ret;
+}
+
+bool chacha20poly1305_decrypt(u8 *dst, const u8 *src, const size_t src_len,
+			      const u8 *ad, const size_t ad_len,
+			      const u64 nonce,
+			      const u8 key[CHACHA20POLY1305_KEY_SIZE])
+{
+	u32 chacha_state[CHACHA_STATE_WORDS];
+	u32 k[CHACHA_KEY_WORDS];
+	__le64 iv[2];
+	bool ret;
+
+	chacha_load_key(k, key);
+
+	iv[0] = 0;
+	iv[1] = cpu_to_le64(nonce);
+
+	chacha_init(chacha_state, k, (u8 *)iv);
+	ret = __chacha20poly1305_decrypt(dst, src, src_len, ad, ad_len,
+					 chacha_state);
+
+	memzero_explicit(chacha_state, sizeof(chacha_state));
+	memzero_explicit(iv, sizeof(iv));
+	memzero_explicit(k, sizeof(k));
+	return ret;
+}
+EXPORT_SYMBOL(chacha20poly1305_decrypt);
+
+bool xchacha20poly1305_decrypt(u8 *dst, const u8 *src, const size_t src_len,
+			       const u8 *ad, const size_t ad_len,
+			       const u8 nonce[XCHACHA20POLY1305_NONCE_SIZE],
+			       const u8 key[CHACHA20POLY1305_KEY_SIZE])
+{
+	u32 chacha_state[CHACHA_STATE_WORDS];
+
+	xchacha_init(chacha_state, key, nonce);
+	return __chacha20poly1305_decrypt(dst, src, src_len, ad, ad_len,
+					  chacha_state);
+}
+EXPORT_SYMBOL(xchacha20poly1305_decrypt);
+
+static
+bool chacha20poly1305_crypt_sg_inplace(struct scatterlist *src,
+				       const size_t src_len,
+				       const u8 *ad, const size_t ad_len,
+				       const u64 nonce,
+				       const u8 key[CHACHA20POLY1305_KEY_SIZE],
+				       int encrypt)
+{
+	const u8 *pad0 = page_address(ZERO_PAGE(0));
+	struct poly1305_desc_ctx poly1305_state;
+	u32 chacha_state[CHACHA_STATE_WORDS];
+	struct sg_mapping_iter miter;
+	size_t partial = 0;
+	unsigned int flags;
+	bool ret = true;
+	int sl;
+	union {
+		struct {
+			u32 k[CHACHA_KEY_WORDS];
+			__le64 iv[2];
+		};
+		u8 block0[POLY1305_KEY_SIZE];
+		u8 chacha_stream[CHACHA_BLOCK_SIZE];
+		struct {
+			u8 mac[2][POLY1305_DIGEST_SIZE];
+		};
+		__le64 lens[2];
+	} b __aligned(16);
+
+	if (WARN_ON(src_len > INT_MAX))
+		return false;
+
+	chacha_load_key(b.k, key);
+
+	b.iv[0] = 0;
+	b.iv[1] = cpu_to_le64(nonce);
+
+	chacha_init(chacha_state, b.k, (u8 *)b.iv);
+	chacha20_crypt(chacha_state, b.block0, pad0, sizeof(b.block0));
+	poly1305_init(&poly1305_state, b.block0);
+
+	if (unlikely(ad_len)) {
+		poly1305_update(&poly1305_state, ad, ad_len);
+		if (ad_len & 0xf)
+			poly1305_update(&poly1305_state, pad0, 0x10 - (ad_len & 0xf));
+	}
+
+	flags = SG_MITER_TO_SG | SG_MITER_ATOMIC;
+
+	sg_miter_start(&miter, src, sg_nents(src), flags);
+
+	for (sl = src_len; sl > 0 && sg_miter_next(&miter); sl -= miter.length) {
+		u8 *addr = miter.addr;
+		size_t length = min_t(size_t, sl, miter.length);
+
+		if (!encrypt)
+			poly1305_update(&poly1305_state, addr, length);
+
+		if (unlikely(partial)) {
+			size_t l = min(length, CHACHA_BLOCK_SIZE - partial);
+
+			crypto_xor(addr, b.chacha_stream + partial, l);
+			partial = (partial + l) & (CHACHA_BLOCK_SIZE - 1);
+
+			addr += l;
+			length -= l;
+		}
+
+		if (likely(length >= CHACHA_BLOCK_SIZE || length == sl)) {
+			size_t l = length;
+
+			if (unlikely(length < sl))
+				l &= ~(CHACHA_BLOCK_SIZE - 1);
+			chacha20_crypt(chacha_state, addr, addr, l);
+			addr += l;
+			length -= l;
+		}
+
+		if (unlikely(length > 0)) {
+			chacha20_crypt(chacha_state, b.chacha_stream, pad0,
+				       CHACHA_BLOCK_SIZE);
+			crypto_xor(addr, b.chacha_stream, length);
+			partial = length;
+		}
+
+		if (encrypt)
+			poly1305_update(&poly1305_state, miter.addr,
+					min_t(size_t, sl, miter.length));
+	}
+
+	if (src_len & 0xf)
+		poly1305_update(&poly1305_state, pad0, 0x10 - (src_len & 0xf));
+
+	b.lens[0] = cpu_to_le64(ad_len);
+	b.lens[1] = cpu_to_le64(src_len);
+	poly1305_update(&poly1305_state, (u8 *)b.lens, sizeof(b.lens));
+
+	if (likely(sl <= -POLY1305_DIGEST_SIZE)) {
+		if (encrypt) {
+			poly1305_final(&poly1305_state,
+				       miter.addr + miter.length + sl);
+			ret = true;
+		} else {
+			poly1305_final(&poly1305_state, b.mac[0]);
+			ret = !crypto_memneq(b.mac[0],
+					     miter.addr + miter.length + sl,
+					     POLY1305_DIGEST_SIZE);
+		}
+	}
+
+	sg_miter_stop(&miter);
+
+	if (unlikely(sl > -POLY1305_DIGEST_SIZE)) {
+		poly1305_final(&poly1305_state, b.mac[1]);
+		scatterwalk_map_and_copy(b.mac[encrypt], src, src_len,
+					 sizeof(b.mac[1]), encrypt);
+		ret = encrypt ||
+		      !crypto_memneq(b.mac[0], b.mac[1], POLY1305_DIGEST_SIZE);
+	}
+
+	memzero_explicit(chacha_state, sizeof(chacha_state));
+	memzero_explicit(&b, sizeof(b));
+
+	return ret;
+}
+
+bool chacha20poly1305_encrypt_sg_inplace(struct scatterlist *src, size_t src_len,
+					 const u8 *ad, const size_t ad_len,
+					 const u64 nonce,
+					 const u8 key[CHACHA20POLY1305_KEY_SIZE])
+{
+	return chacha20poly1305_crypt_sg_inplace(src, src_len, ad, ad_len,
+						 nonce, key, 1);
+}
+EXPORT_SYMBOL(chacha20poly1305_encrypt_sg_inplace);
+
+bool chacha20poly1305_decrypt_sg_inplace(struct scatterlist *src, size_t src_len,
+					 const u8 *ad, const size_t ad_len,
+					 const u64 nonce,
+					 const u8 key[CHACHA20POLY1305_KEY_SIZE])
+{
+	if (unlikely(src_len < POLY1305_DIGEST_SIZE))
+		return false;
+
+	return chacha20poly1305_crypt_sg_inplace(src,
+						 src_len - POLY1305_DIGEST_SIZE,
+						 ad, ad_len, nonce, key, 0);
+}
+EXPORT_SYMBOL(chacha20poly1305_decrypt_sg_inplace);
+
+static int __init mod_init(void)
+{
+	if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS) &&
+	    WARN_ON(!chacha20poly1305_selftest()))
+		return -ENODEV;
+	return 0;
+}
+
+module_init(mod_init);
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("ChaCha20Poly1305 AEAD construction");
+MODULE_AUTHOR("Jason A. Donenfeld <Jason@zx2c4.com>");