crypto: sha512 - Replace sha512_generic with wrapper around SHA-512 library

Delete crypto/sha512_generic.c, which provided "generic" SHA-384 and
SHA-512 crypto_shash algorithms.  Replace it with crypto/sha512.c which
provides SHA-384, SHA-512, HMAC-SHA384, and HMAC-SHA512 crypto_shash
algorithms using the corresponding library functions.

This is a prerequisite for migrating all the arch-optimized SHA-512 code
(which is almost 3000 lines) to lib/crypto/ rather than duplicating it.

Since the replacement crypto_shash algorithms are implemented using the
(potentially arch-optimized) library functions, give them
cra_driver_names ending with "-lib" rather than "-generic".  Update
crypto/testmgr.c and one odd driver to take this change in driver name
into account.  Besides these cases which are accounted for, there are no
known cases where the cra_driver_name was being depended on.

This change does mean that the abstract partial block handling code in
crypto/shash.c, which got added in 6.16, no longer gets used.  But
that's fine; the library has to implement the partial block handling
anyway, and it's better to do it in the library since the block size and
other properties of the algorithm are all fixed at compile time there,
resulting in more streamlined code.

Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250630160320.2888-6-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

1 files changed, 258 insertions, 0 deletions

diff --git a/crypto/sha512.c b/crypto/sha512.c
new file mode 100644
index 000000000000..d1e5400fe590
--- /dev/null
+++ b/crypto/sha512.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Crypto API support for SHA-384, SHA-512, HMAC-SHA384, and HMAC-SHA512
+ *
+ * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
+ * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
+ * Copyright (c) 2003 Kyle McMartin <kyle@debian.org>
+ * Copyright 2025 Google LLC
+ */
+#include <crypto/internal/hash.h>
+#include <crypto/sha2.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+/* SHA-384 */
+
+const u8 sha384_zero_message_hash[SHA384_DIGEST_SIZE] = {
+	0x38, 0xb0, 0x60, 0xa7, 0x51, 0xac, 0x96, 0x38,
+	0x4c, 0xd9, 0x32, 0x7e, 0xb1, 0xb1, 0xe3, 0x6a,
+	0x21, 0xfd, 0xb7, 0x11, 0x14, 0xbe, 0x07, 0x43,
+	0x4c, 0x0c, 0xc7, 0xbf, 0x63, 0xf6, 0xe1, 0xda,
+	0x27, 0x4e, 0xde, 0xbf, 0xe7, 0x6f, 0x65, 0xfb,
+	0xd5, 0x1a, 0xd2, 0xf1, 0x48, 0x98, 0xb9, 0x5b
+};
+EXPORT_SYMBOL_GPL(sha384_zero_message_hash);
+
+#define SHA384_CTX(desc) ((struct sha384_ctx *)shash_desc_ctx(desc))
+
+static int crypto_sha384_init(struct shash_desc *desc)
+{
+	sha384_init(SHA384_CTX(desc));
+	return 0;
+}
+
+static int crypto_sha384_update(struct shash_desc *desc,
+				const u8 *data, unsigned int len)
+{
+	sha384_update(SHA384_CTX(desc), data, len);
+	return 0;
+}
+
+static int crypto_sha384_final(struct shash_desc *desc, u8 *out)
+{
+	sha384_final(SHA384_CTX(desc), out);
+	return 0;
+}
+
+static int crypto_sha384_digest(struct shash_desc *desc,
+				const u8 *data, unsigned int len, u8 *out)
+{
+	sha384(data, len, out);
+	return 0;
+}
+
+/* SHA-512 */
+
+const u8 sha512_zero_message_hash[SHA512_DIGEST_SIZE] = {
+	0xcf, 0x83, 0xe1, 0x35, 0x7e, 0xef, 0xb8, 0xbd,
+	0xf1, 0x54, 0x28, 0x50, 0xd6, 0x6d, 0x80, 0x07,
+	0xd6, 0x20, 0xe4, 0x05, 0x0b, 0x57, 0x15, 0xdc,
+	0x83, 0xf4, 0xa9, 0x21, 0xd3, 0x6c, 0xe9, 0xce,
+	0x47, 0xd0, 0xd1, 0x3c, 0x5d, 0x85, 0xf2, 0xb0,
+	0xff, 0x83, 0x18, 0xd2, 0x87, 0x7e, 0xec, 0x2f,
+	0x63, 0xb9, 0x31, 0xbd, 0x47, 0x41, 0x7a, 0x81,
+	0xa5, 0x38, 0x32, 0x7a, 0xf9, 0x27, 0xda, 0x3e
+};
+EXPORT_SYMBOL_GPL(sha512_zero_message_hash);
+
+#define SHA512_CTX(desc) ((struct sha512_ctx *)shash_desc_ctx(desc))
+
+static int crypto_sha512_init(struct shash_desc *desc)
+{
+	sha512_init(SHA512_CTX(desc));
+	return 0;
+}
+
+static int crypto_sha512_update(struct shash_desc *desc,
+				const u8 *data, unsigned int len)
+{
+	sha512_update(SHA512_CTX(desc), data, len);
+	return 0;
+}
+
+static int crypto_sha512_final(struct shash_desc *desc, u8 *out)
+{
+	sha512_final(SHA512_CTX(desc), out);
+	return 0;
+}
+
+static int crypto_sha512_digest(struct shash_desc *desc,
+				const u8 *data, unsigned int len, u8 *out)
+{
+	sha512(data, len, out);
+	return 0;
+}
+
+/* HMAC-SHA384 */
+
+#define HMAC_SHA384_KEY(tfm) ((struct hmac_sha384_key *)crypto_shash_ctx(tfm))
+#define HMAC_SHA384_CTX(desc) ((struct hmac_sha384_ctx *)shash_desc_ctx(desc))
+
+static int crypto_hmac_sha384_setkey(struct crypto_shash *tfm,
+				     const u8 *raw_key, unsigned int keylen)
+{
+	hmac_sha384_preparekey(HMAC_SHA384_KEY(tfm), raw_key, keylen);
+	return 0;
+}
+
+static int crypto_hmac_sha384_init(struct shash_desc *desc)
+{
+	hmac_sha384_init(HMAC_SHA384_CTX(desc), HMAC_SHA384_KEY(desc->tfm));
+	return 0;
+}
+
+static int crypto_hmac_sha384_update(struct shash_desc *desc,
+				     const u8 *data, unsigned int len)
+{
+	hmac_sha384_update(HMAC_SHA384_CTX(desc), data, len);
+	return 0;
+}
+
+static int crypto_hmac_sha384_final(struct shash_desc *desc, u8 *out)
+{
+	hmac_sha384_final(HMAC_SHA384_CTX(desc), out);
+	return 0;
+}
+
+static int crypto_hmac_sha384_digest(struct shash_desc *desc,
+				     const u8 *data, unsigned int len,
+				     u8 *out)
+{
+	hmac_sha384(HMAC_SHA384_KEY(desc->tfm), data, len, out);
+	return 0;
+}
+
+/* HMAC-SHA512 */
+
+#define HMAC_SHA512_KEY(tfm) ((struct hmac_sha512_key *)crypto_shash_ctx(tfm))
+#define HMAC_SHA512_CTX(desc) ((struct hmac_sha512_ctx *)shash_desc_ctx(desc))
+
+static int crypto_hmac_sha512_setkey(struct crypto_shash *tfm,
+				     const u8 *raw_key, unsigned int keylen)
+{
+	hmac_sha512_preparekey(HMAC_SHA512_KEY(tfm), raw_key, keylen);
+	return 0;
+}
+
+static int crypto_hmac_sha512_init(struct shash_desc *desc)
+{
+	hmac_sha512_init(HMAC_SHA512_CTX(desc), HMAC_SHA512_KEY(desc->tfm));
+	return 0;
+}
+
+static int crypto_hmac_sha512_update(struct shash_desc *desc,
+				     const u8 *data, unsigned int len)
+{
+	hmac_sha512_update(HMAC_SHA512_CTX(desc), data, len);
+	return 0;
+}
+
+static int crypto_hmac_sha512_final(struct shash_desc *desc, u8 *out)
+{
+	hmac_sha512_final(HMAC_SHA512_CTX(desc), out);
+	return 0;
+}
+
+static int crypto_hmac_sha512_digest(struct shash_desc *desc,
+				     const u8 *data, unsigned int len,
+				     u8 *out)
+{
+	hmac_sha512(HMAC_SHA512_KEY(desc->tfm), data, len, out);
+	return 0;
+}
+
+/* Algorithm definitions */
+
+static struct shash_alg algs[] = {
+	{
+		.base.cra_name		= "sha384",
+		.base.cra_driver_name	= "sha384-lib",
+		.base.cra_priority	= 300,
+		.base.cra_blocksize	= SHA384_BLOCK_SIZE,
+		.base.cra_module	= THIS_MODULE,
+		.digestsize		= SHA384_DIGEST_SIZE,
+		.init			= crypto_sha384_init,
+		.update			= crypto_sha384_update,
+		.final			= crypto_sha384_final,
+		.digest			= crypto_sha384_digest,
+		.descsize		= sizeof(struct sha384_ctx),
+	},
+	{
+		.base.cra_name		= "sha512",
+		.base.cra_driver_name	= "sha512-lib",
+		.base.cra_priority	= 300,
+		.base.cra_blocksize	= SHA512_BLOCK_SIZE,
+		.base.cra_module	= THIS_MODULE,
+		.digestsize		= SHA512_DIGEST_SIZE,
+		.init			= crypto_sha512_init,
+		.update			= crypto_sha512_update,
+		.final			= crypto_sha512_final,
+		.digest			= crypto_sha512_digest,
+		.descsize		= sizeof(struct sha512_ctx),
+	},
+	{
+		.base.cra_name		= "hmac(sha384)",
+		.base.cra_driver_name	= "hmac-sha384-lib",
+		.base.cra_priority	= 300,
+		.base.cra_blocksize	= SHA384_BLOCK_SIZE,
+		.base.cra_ctxsize	= sizeof(struct hmac_sha384_key),
+		.base.cra_module	= THIS_MODULE,
+		.digestsize		= SHA384_DIGEST_SIZE,
+		.setkey			= crypto_hmac_sha384_setkey,
+		.init			= crypto_hmac_sha384_init,
+		.update			= crypto_hmac_sha384_update,
+		.final			= crypto_hmac_sha384_final,
+		.digest			= crypto_hmac_sha384_digest,
+		.descsize		= sizeof(struct hmac_sha384_ctx),
+	},
+	{
+		.base.cra_name		= "hmac(sha512)",
+		.base.cra_driver_name	= "hmac-sha512-lib",
+		.base.cra_priority	= 300,
+		.base.cra_blocksize	= SHA512_BLOCK_SIZE,
+		.base.cra_ctxsize	= sizeof(struct hmac_sha512_key),
+		.base.cra_module	= THIS_MODULE,
+		.digestsize		= SHA512_DIGEST_SIZE,
+		.setkey			= crypto_hmac_sha512_setkey,
+		.init			= crypto_hmac_sha512_init,
+		.update			= crypto_hmac_sha512_update,
+		.final			= crypto_hmac_sha512_final,
+		.digest			= crypto_hmac_sha512_digest,
+		.descsize		= sizeof(struct hmac_sha512_ctx),
+	},
+};
+
+static int __init crypto_sha512_mod_init(void)
+{
+	return crypto_register_shashes(algs, ARRAY_SIZE(algs));
+}
+module_init(crypto_sha512_mod_init);
+
+static void __exit crypto_sha512_mod_exit(void)
+{
+	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
+}
+module_exit(crypto_sha512_mod_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Crypto API support for SHA-384, SHA-512, HMAC-SHA384, and HMAC-SHA512");
+
+MODULE_ALIAS_CRYPTO("sha384");
+MODULE_ALIAS_CRYPTO("sha384-lib");
+MODULE_ALIAS_CRYPTO("sha512");
+MODULE_ALIAS_CRYPTO("sha512-lib");
+MODULE_ALIAS_CRYPTO("hmac(sha384)");
+MODULE_ALIAS_CRYPTO("hmac-sha384-lib");
+MODULE_ALIAS_CRYPTO("hmac(sha512)");
+MODULE_ALIAS_CRYPTO("hmac-sha512-lib");