1 files changed, 419 insertions, 4 deletions

diff --git a/arch/arm/crypto/ghash-ce-glue.c b/arch/arm/crypto/ghash-ce-glue.c
index f13401f3e669..3ddf05b4234d 100644
--- a/arch/arm/crypto/ghash-ce-glue.c
+++ b/arch/arm/crypto/ghash-ce-glue.c
@@ -2,36 +2,53 @@
 /*
  * Accelerated GHASH implementation with ARMv8 vmull.p64 instructions.
  *
- * Copyright (C) 2015 - 2018 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ * Copyright (C) 2015 - 2018 Linaro Ltd.
+ * Copyright (C) 2023 Google LLC.
  */
 
 #include <asm/hwcap.h>
 #include <asm/neon.h>
 #include <asm/simd.h>
 #include <asm/unaligned.h>
+#include <crypto/aes.h>
+#include <crypto/gcm.h>
 #include <crypto/b128ops.h>
 #include <crypto/cryptd.h>
+#include <crypto/internal/aead.h>
 #include <crypto/internal/hash.h>
 #include <crypto/internal/simd.h>
+#include <crypto/internal/skcipher.h>
 #include <crypto/gf128mul.h>
+#include <crypto/scatterwalk.h>
 #include <linux/cpufeature.h>
 #include <linux/crypto.h>
 #include <linux/jump_label.h>
 #include <linux/module.h>
 
 MODULE_DESCRIPTION("GHASH hash function using ARMv8 Crypto Extensions");
-MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
-MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Ard Biesheuvel <ardb@kernel.org>");
+MODULE_LICENSE("GPL");
 MODULE_ALIAS_CRYPTO("ghash");
+MODULE_ALIAS_CRYPTO("gcm(aes)");
+MODULE_ALIAS_CRYPTO("rfc4106(gcm(aes))");
 
 #define GHASH_BLOCK_SIZE	16
 #define GHASH_DIGEST_SIZE	16
 
+#define RFC4106_NONCE_SIZE	4
+
 struct ghash_key {
 	be128	k;
 	u64	h[][2];
 };
 
+struct gcm_key {
+	u64	h[4][2];
+	u32	rk[AES_MAX_KEYLENGTH_U32];
+	int	rounds;
+	u8	nonce[];	// for RFC4106 nonce
+};
+
 struct ghash_desc_ctx {
 	u64 digest[GHASH_DIGEST_SIZE/sizeof(u64)];
 	u8 buf[GHASH_BLOCK_SIZE];
@@ -344,6 +361,393 @@ static struct ahash_alg ghash_async_alg = {
 	},
 };
 
+
+void pmull_gcm_encrypt(int blocks, u64 dg[], const char *src,
+		       struct gcm_key const *k, char *dst,
+		       const char *iv, int rounds, u32 counter);
+
+void pmull_gcm_enc_final(int blocks, u64 dg[], char *tag,
+			 struct gcm_key const *k, char *head,
+			 const char *iv, int rounds, u32 counter);
+
+void pmull_gcm_decrypt(int bytes, u64 dg[], const char *src,
+		       struct gcm_key const *k, char *dst,
+		       const char *iv, int rounds, u32 counter);
+
+int pmull_gcm_dec_final(int bytes, u64 dg[], char *tag,
+			struct gcm_key const *k, char *head,
+			const char *iv, int rounds, u32 counter,
+			const char *otag, int authsize);
+
+static int gcm_aes_setkey(struct crypto_aead *tfm, const u8 *inkey,
+			  unsigned int keylen)
+{
+	struct gcm_key *ctx = crypto_aead_ctx(tfm);
+	struct crypto_aes_ctx aes_ctx;
+	be128 h, k;
+	int ret;
+
+	ret = aes_expandkey(&aes_ctx, inkey, keylen);
+	if (ret)
+		return -EINVAL;
+
+	aes_encrypt(&aes_ctx, (u8 *)&k, (u8[AES_BLOCK_SIZE]){});
+
+	memcpy(ctx->rk, aes_ctx.key_enc, sizeof(ctx->rk));
+	ctx->rounds = 6 + keylen / 4;
+
+	memzero_explicit(&aes_ctx, sizeof(aes_ctx));
+
+	ghash_reflect(ctx->h[0], &k);
+
+	h = k;
+	gf128mul_lle(&h, &k);
+	ghash_reflect(ctx->h[1], &h);
+
+	gf128mul_lle(&h, &k);
+	ghash_reflect(ctx->h[2], &h);
+
+	gf128mul_lle(&h, &k);
+	ghash_reflect(ctx->h[3], &h);
+
+	return 0;
+}
+
+static int gcm_aes_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
+{
+	return crypto_gcm_check_authsize(authsize);
+}
+
+static void gcm_update_mac(u64 dg[], const u8 *src, int count, u8 buf[],
+			   int *buf_count, struct gcm_key *ctx)
+{
+	if (*buf_count > 0) {
+		int buf_added = min(count, GHASH_BLOCK_SIZE - *buf_count);
+
+		memcpy(&buf[*buf_count], src, buf_added);
+
+		*buf_count += buf_added;
+		src += buf_added;
+		count -= buf_added;
+	}
+
+	if (count >= GHASH_BLOCK_SIZE || *buf_count == GHASH_BLOCK_SIZE) {
+		int blocks = count / GHASH_BLOCK_SIZE;
+
+		pmull_ghash_update_p64(blocks, dg, src, ctx->h,
+				       *buf_count ? buf : NULL);
+
+		src += blocks * GHASH_BLOCK_SIZE;
+		count %= GHASH_BLOCK_SIZE;
+		*buf_count = 0;
+	}
+
+	if (count > 0) {
+		memcpy(buf, src, count);
+		*buf_count = count;
+	}
+}
+
+static void gcm_calculate_auth_mac(struct aead_request *req, u64 dg[], u32 len)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	struct gcm_key *ctx = crypto_aead_ctx(aead);
+	u8 buf[GHASH_BLOCK_SIZE];
+	struct scatter_walk walk;
+	int buf_count = 0;
+
+	scatterwalk_start(&walk, req->src);
+
+	do {
+		u32 n = scatterwalk_clamp(&walk, len);
+		u8 *p;
+
+		if (!n) {
+			scatterwalk_start(&walk, sg_next(walk.sg));
+			n = scatterwalk_clamp(&walk, len);
+		}
+
+		p = scatterwalk_map(&walk);
+		gcm_update_mac(dg, p, n, buf, &buf_count, ctx);
+		scatterwalk_unmap(p);
+
+		if (unlikely(len / SZ_4K > (len - n) / SZ_4K)) {
+			kernel_neon_end();
+			kernel_neon_begin();
+		}
+
+		len -= n;
+		scatterwalk_advance(&walk, n);
+		scatterwalk_done(&walk, 0, len);
+	} while (len);
+
+	if (buf_count) {
+		memset(&buf[buf_count], 0, GHASH_BLOCK_SIZE - buf_count);
+		pmull_ghash_update_p64(1, dg, buf, ctx->h, NULL);
+	}
+}
+
+static int gcm_encrypt(struct aead_request *req, const u8 *iv, u32 assoclen)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	struct gcm_key *ctx = crypto_aead_ctx(aead);
+	struct skcipher_walk walk;
+	u8 buf[AES_BLOCK_SIZE];
+	u32 counter = 2;
+	u64 dg[2] = {};
+	be128 lengths;
+	const u8 *src;
+	u8 *tag, *dst;
+	int tail, err;
+
+	if (WARN_ON_ONCE(!may_use_simd()))
+		return -EBUSY;
+
+	err = skcipher_walk_aead_encrypt(&walk, req, false);
+
+	kernel_neon_begin();
+
+	if (assoclen)
+		gcm_calculate_auth_mac(req, dg, assoclen);
+
+	src = walk.src.virt.addr;
+	dst = walk.dst.virt.addr;
+
+	while (walk.nbytes >= AES_BLOCK_SIZE) {
+		int nblocks = walk.nbytes / AES_BLOCK_SIZE;
+
+		pmull_gcm_encrypt(nblocks, dg, src, ctx, dst, iv,
+				  ctx->rounds, counter);
+		counter += nblocks;
+
+		if (walk.nbytes == walk.total) {
+			src += nblocks * AES_BLOCK_SIZE;
+			dst += nblocks * AES_BLOCK_SIZE;
+			break;
+		}
+
+		kernel_neon_end();
+
+		err = skcipher_walk_done(&walk,
+					 walk.nbytes % AES_BLOCK_SIZE);
+		if (err)
+			return err;
+
+		src = walk.src.virt.addr;
+		dst = walk.dst.virt.addr;
+
+		kernel_neon_begin();
+	}
+
+
+	lengths.a = cpu_to_be64(assoclen * 8);
+	lengths.b = cpu_to_be64(req->cryptlen * 8);
+
+	tag = (u8 *)&lengths;
+	tail = walk.nbytes % AES_BLOCK_SIZE;
+
+	/*
+	 * Bounce via a buffer unless we are encrypting in place and src/dst
+	 * are not pointing to the start of the walk buffer. In that case, we
+	 * can do a NEON load/xor/store sequence in place as long as we move
+	 * the plain/ciphertext and keystream to the start of the register. If
+	 * not, do a memcpy() to the end of the buffer so we can reuse the same
+	 * logic.
+	 */
+	if (unlikely(tail && (tail == walk.nbytes || src != dst)))
+		src = memcpy(buf + sizeof(buf) - tail, src, tail);
+
+	pmull_gcm_enc_final(tail, dg, tag, ctx, (u8 *)src, iv,
+			    ctx->rounds, counter);
+	kernel_neon_end();
+
+	if (unlikely(tail && src != dst))
+		memcpy(dst, src, tail);
+
+	if (walk.nbytes) {
+		err = skcipher_walk_done(&walk, 0);
+		if (err)
+			return err;
+	}
+
+	/* copy authtag to end of dst */
+	scatterwalk_map_and_copy(tag, req->dst, req->assoclen + req->cryptlen,
+				 crypto_aead_authsize(aead), 1);
+
+	return 0;
+}
+
+static int gcm_decrypt(struct aead_request *req, const u8 *iv, u32 assoclen)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	struct gcm_key *ctx = crypto_aead_ctx(aead);
+	int authsize = crypto_aead_authsize(aead);
+	struct skcipher_walk walk;
+	u8 otag[AES_BLOCK_SIZE];
+	u8 buf[AES_BLOCK_SIZE];
+	u32 counter = 2;
+	u64 dg[2] = {};
+	be128 lengths;
+	const u8 *src;
+	u8 *tag, *dst;
+	int tail, err, ret;
+
+	if (WARN_ON_ONCE(!may_use_simd()))
+		return -EBUSY;
+
+	scatterwalk_map_and_copy(otag, req->src,
+				 req->assoclen + req->cryptlen - authsize,
+				 authsize, 0);
+
+	err = skcipher_walk_aead_decrypt(&walk, req, false);
+
+	kernel_neon_begin();
+
+	if (assoclen)
+		gcm_calculate_auth_mac(req, dg, assoclen);
+
+	src = walk.src.virt.addr;
+	dst = walk.dst.virt.addr;
+
+	while (walk.nbytes >= AES_BLOCK_SIZE) {
+		int nblocks = walk.nbytes / AES_BLOCK_SIZE;
+
+		pmull_gcm_decrypt(nblocks, dg, src, ctx, dst, iv,
+				  ctx->rounds, counter);
+		counter += nblocks;
+
+		if (walk.nbytes == walk.total) {
+			src += nblocks * AES_BLOCK_SIZE;
+			dst += nblocks * AES_BLOCK_SIZE;
+			break;
+		}
+
+		kernel_neon_end();
+
+		err = skcipher_walk_done(&walk,
+					 walk.nbytes % AES_BLOCK_SIZE);
+		if (err)
+			return err;
+
+		src = walk.src.virt.addr;
+		dst = walk.dst.virt.addr;
+
+		kernel_neon_begin();
+	}
+
+	lengths.a = cpu_to_be64(assoclen * 8);
+	lengths.b = cpu_to_be64((req->cryptlen - authsize) * 8);
+
+	tag = (u8 *)&lengths;
+	tail = walk.nbytes % AES_BLOCK_SIZE;
+
+	if (unlikely(tail && (tail == walk.nbytes || src != dst)))
+		src = memcpy(buf + sizeof(buf) - tail, src, tail);
+
+	ret = pmull_gcm_dec_final(tail, dg, tag, ctx, (u8 *)src, iv,
+				  ctx->rounds, counter, otag, authsize);
+	kernel_neon_end();
+
+	if (unlikely(tail && src != dst))
+		memcpy(dst, src, tail);
+
+	if (walk.nbytes) {
+		err = skcipher_walk_done(&walk, 0);
+		if (err)
+			return err;
+	}
+
+	return ret ? -EBADMSG : 0;
+}
+
+static int gcm_aes_encrypt(struct aead_request *req)
+{
+	return gcm_encrypt(req, req->iv, req->assoclen);
+}
+
+static int gcm_aes_decrypt(struct aead_request *req)
+{
+	return gcm_decrypt(req, req->iv, req->assoclen);
+}
+
+static int rfc4106_setkey(struct crypto_aead *tfm, const u8 *inkey,
+			  unsigned int keylen)
+{
+	struct gcm_key *ctx = crypto_aead_ctx(tfm);
+	int err;
+
+	keylen -= RFC4106_NONCE_SIZE;
+	err = gcm_aes_setkey(tfm, inkey, keylen);
+	if (err)
+		return err;
+
+	memcpy(ctx->nonce, inkey + keylen, RFC4106_NONCE_SIZE);
+	return 0;
+}
+
+static int rfc4106_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
+{
+	return crypto_rfc4106_check_authsize(authsize);
+}
+
+static int rfc4106_encrypt(struct aead_request *req)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	struct gcm_key *ctx = crypto_aead_ctx(aead);
+	u8 iv[GCM_AES_IV_SIZE];
+
+	memcpy(iv, ctx->nonce, RFC4106_NONCE_SIZE);
+	memcpy(iv + RFC4106_NONCE_SIZE, req->iv, GCM_RFC4106_IV_SIZE);
+
+	return crypto_ipsec_check_assoclen(req->assoclen) ?:
+	       gcm_encrypt(req, iv, req->assoclen - GCM_RFC4106_IV_SIZE);
+}
+
+static int rfc4106_decrypt(struct aead_request *req)
+{
+	struct crypto_aead *aead = crypto_aead_reqtfm(req);
+	struct gcm_key *ctx = crypto_aead_ctx(aead);
+	u8 iv[GCM_AES_IV_SIZE];
+
+	memcpy(iv, ctx->nonce, RFC4106_NONCE_SIZE);
+	memcpy(iv + RFC4106_NONCE_SIZE, req->iv, GCM_RFC4106_IV_SIZE);
+
+	return crypto_ipsec_check_assoclen(req->assoclen) ?:
+	       gcm_decrypt(req, iv, req->assoclen - GCM_RFC4106_IV_SIZE);
+}
+
+static struct aead_alg gcm_aes_algs[] = {{
+	.ivsize			= GCM_AES_IV_SIZE,
+	.chunksize		= AES_BLOCK_SIZE,
+	.maxauthsize		= AES_BLOCK_SIZE,
+	.setkey			= gcm_aes_setkey,
+	.setauthsize		= gcm_aes_setauthsize,
+	.encrypt		= gcm_aes_encrypt,
+	.decrypt		= gcm_aes_decrypt,
+
+	.base.cra_name		= "gcm(aes)",
+	.base.cra_driver_name	= "gcm-aes-ce",
+	.base.cra_priority	= 400,
+	.base.cra_blocksize	= 1,
+	.base.cra_ctxsize	= sizeof(struct gcm_key),
+	.base.cra_module	= THIS_MODULE,
+}, {
+	.ivsize			= GCM_RFC4106_IV_SIZE,
+	.chunksize		= AES_BLOCK_SIZE,
+	.maxauthsize		= AES_BLOCK_SIZE,
+	.setkey			= rfc4106_setkey,
+	.setauthsize		= rfc4106_setauthsize,
+	.encrypt		= rfc4106_encrypt,
+	.decrypt		= rfc4106_decrypt,
+
+	.base.cra_name		= "rfc4106(gcm(aes))",
+	.base.cra_driver_name	= "rfc4106-gcm-aes-ce",
+	.base.cra_priority	= 400,
+	.base.cra_blocksize	= 1,
+	.base.cra_ctxsize	= sizeof(struct gcm_key) + RFC4106_NONCE_SIZE,
+	.base.cra_module	= THIS_MODULE,
+}};
+
 static int __init ghash_ce_mod_init(void)
 {
 	int err;
@@ -352,13 +756,17 @@ static int __init ghash_ce_mod_init(void)
 		return -ENODEV;
 
 	if (elf_hwcap2 & HWCAP2_PMULL) {
+		err = crypto_register_aeads(gcm_aes_algs,
+					    ARRAY_SIZE(gcm_aes_algs));
+		if (err)
+			return err;
 		ghash_alg.base.cra_ctxsize += 3 * sizeof(u64[2]);
 		static_branch_enable(&use_p64);
 	}
 
 	err = crypto_register_shash(&ghash_alg);
 	if (err)
-		return err;
+		goto err_aead;
 	err = crypto_register_ahash(&ghash_async_alg);
 	if (err)
 		goto err_shash;
@@ -367,6 +775,10 @@ static int __init ghash_ce_mod_init(void)
 
 err_shash:
 	crypto_unregister_shash(&ghash_alg);
+err_aead:
+	if (elf_hwcap2 & HWCAP2_PMULL)
+		crypto_unregister_aeads(gcm_aes_algs,
+					ARRAY_SIZE(gcm_aes_algs));
 	return err;
 }
 
@@ -374,6 +786,9 @@ static void __exit ghash_ce_mod_exit(void)
 {
 	crypto_unregister_ahash(&ghash_async_alg);
 	crypto_unregister_shash(&ghash_alg);
+	if (elf_hwcap2 & HWCAP2_PMULL)
+		crypto_unregister_aeads(gcm_aes_algs,
+					ARRAY_SIZE(gcm_aes_algs));
 }
 
 module_init(ghash_ce_mod_init);