Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 431 insertions, 0 deletions

diff --git a/crypto/lrw.c b/crypto/lrw.c
new file mode 100644
index 0000000000..59260aefed
--- /dev/null
+++ b/crypto/lrw.c
@@ -0,0 +1,431 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* LRW: as defined by Cyril Guyot in
+ *	http://grouper.ieee.org/groups/1619/email/pdf00017.pdf
+ *
+ * Copyright (c) 2006 Rik Snel <rsnel@cube.dyndns.org>
+ *
+ * Based on ecb.c
+ * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+/* This implementation is checked against the test vectors in the above
+ * document and by a test vector provided by Ken Buchanan at
+ * https://www.mail-archive.com/stds-p1619@listserv.ieee.org/msg00173.html
+ *
+ * The test vectors are included in the testing module tcrypt.[ch] */
+
+#include <crypto/internal/skcipher.h>
+#include <crypto/scatterwalk.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+
+#include <crypto/b128ops.h>
+#include <crypto/gf128mul.h>
+
+#define LRW_BLOCK_SIZE 16
+
+struct lrw_tfm_ctx {
+	struct crypto_skcipher *child;
+
+	/*
+	 * optimizes multiplying a random (non incrementing, as at the
+	 * start of a new sector) value with key2, we could also have
+	 * used 4k optimization tables or no optimization at all. In the
+	 * latter case we would have to store key2 here
+	 */
+	struct gf128mul_64k *table;
+
+	/*
+	 * stores:
+	 *  key2*{ 0,0,...0,0,0,0,1 }, key2*{ 0,0,...0,0,0,1,1 },
+	 *  key2*{ 0,0,...0,0,1,1,1 }, key2*{ 0,0,...0,1,1,1,1 }
+	 *  key2*{ 0,0,...1,1,1,1,1 }, etc
+	 * needed for optimized multiplication of incrementing values
+	 * with key2
+	 */
+	be128 mulinc[128];
+};
+
+struct lrw_request_ctx {
+	be128 t;
+	struct skcipher_request subreq;
+};
+
+static inline void lrw_setbit128_bbe(void *b, int bit)
+{
+	__set_bit(bit ^ (0x80 -
+#ifdef __BIG_ENDIAN
+			 BITS_PER_LONG
+#else
+			 BITS_PER_BYTE
+#endif
+			), b);
+}
+
+static int lrw_setkey(struct crypto_skcipher *parent, const u8 *key,
+		      unsigned int keylen)
+{
+	struct lrw_tfm_ctx *ctx = crypto_skcipher_ctx(parent);
+	struct crypto_skcipher *child = ctx->child;
+	int err, bsize = LRW_BLOCK_SIZE;
+	const u8 *tweak = key + keylen - bsize;
+	be128 tmp = { 0 };
+	int i;
+
+	crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
+	crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) &
+					 CRYPTO_TFM_REQ_MASK);
+	err = crypto_skcipher_setkey(child, key, keylen - bsize);
+	if (err)
+		return err;
+
+	if (ctx->table)
+		gf128mul_free_64k(ctx->table);
+
+	/* initialize multiplication table for Key2 */
+	ctx->table = gf128mul_init_64k_bbe((be128 *)tweak);
+	if (!ctx->table)
+		return -ENOMEM;
+
+	/* initialize optimization table */
+	for (i = 0; i < 128; i++) {
+		lrw_setbit128_bbe(&tmp, i);
+		ctx->mulinc[i] = tmp;
+		gf128mul_64k_bbe(&ctx->mulinc[i], ctx->table);
+	}
+
+	return 0;
+}
+
+/*
+ * Returns the number of trailing '1' bits in the words of the counter, which is
+ * represented by 4 32-bit words, arranged from least to most significant.
+ * At the same time, increments the counter by one.
+ *
+ * For example:
+ *
+ * u32 counter[4] = { 0xFFFFFFFF, 0x1, 0x0, 0x0 };
+ * int i = lrw_next_index(&counter);
+ * // i == 33, counter == { 0x0, 0x2, 0x0, 0x0 }
+ */
+static int lrw_next_index(u32 *counter)
+{
+	int i, res = 0;
+
+	for (i = 0; i < 4; i++) {
+		if (counter[i] + 1 != 0)
+			return res + ffz(counter[i]++);
+
+		counter[i] = 0;
+		res += 32;
+	}
+
+	/*
+	 * If we get here, then x == 128 and we are incrementing the counter
+	 * from all ones to all zeros. This means we must return index 127, i.e.
+	 * the one corresponding to key2*{ 1,...,1 }.
+	 */
+	return 127;
+}
+
+/*
+ * We compute the tweak masks twice (both before and after the ECB encryption or
+ * decryption) to avoid having to allocate a temporary buffer and/or make
+ * mutliple calls to the 'ecb(..)' instance, which usually would be slower than
+ * just doing the lrw_next_index() calls again.
+ */
+static int lrw_xor_tweak(struct skcipher_request *req, bool second_pass)
+{
+	const int bs = LRW_BLOCK_SIZE;
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	const struct lrw_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+	struct lrw_request_ctx *rctx = skcipher_request_ctx(req);
+	be128 t = rctx->t;
+	struct skcipher_walk w;
+	__be32 *iv;
+	u32 counter[4];
+	int err;
+
+	if (second_pass) {
+		req = &rctx->subreq;
+		/* set to our TFM to enforce correct alignment: */
+		skcipher_request_set_tfm(req, tfm);
+	}
+
+	err = skcipher_walk_virt(&w, req, false);
+	if (err)
+		return err;
+
+	iv = (__be32 *)w.iv;
+	counter[0] = be32_to_cpu(iv[3]);
+	counter[1] = be32_to_cpu(iv[2]);
+	counter[2] = be32_to_cpu(iv[1]);
+	counter[3] = be32_to_cpu(iv[0]);
+
+	while (w.nbytes) {
+		unsigned int avail = w.nbytes;
+		be128 *wsrc;
+		be128 *wdst;
+
+		wsrc = w.src.virt.addr;
+		wdst = w.dst.virt.addr;
+
+		do {
+			be128_xor(wdst++, &t, wsrc++);
+
+			/* T <- I*Key2, using the optimization
+			 * discussed in the specification */
+			be128_xor(&t, &t,
+				  &ctx->mulinc[lrw_next_index(counter)]);
+		} while ((avail -= bs) >= bs);
+
+		if (second_pass && w.nbytes == w.total) {
+			iv[0] = cpu_to_be32(counter[3]);
+			iv[1] = cpu_to_be32(counter[2]);
+			iv[2] = cpu_to_be32(counter[1]);
+			iv[3] = cpu_to_be32(counter[0]);
+		}
+
+		err = skcipher_walk_done(&w, avail);
+	}
+
+	return err;
+}
+
+static int lrw_xor_tweak_pre(struct skcipher_request *req)
+{
+	return lrw_xor_tweak(req, false);
+}
+
+static int lrw_xor_tweak_post(struct skcipher_request *req)
+{
+	return lrw_xor_tweak(req, true);
+}
+
+static void lrw_crypt_done(void *data, int err)
+{
+	struct skcipher_request *req = data;
+
+	if (!err) {
+		struct lrw_request_ctx *rctx = skcipher_request_ctx(req);
+
+		rctx->subreq.base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+		err = lrw_xor_tweak_post(req);
+	}
+
+	skcipher_request_complete(req, err);
+}
+
+static void lrw_init_crypt(struct skcipher_request *req)
+{
+	const struct lrw_tfm_ctx *ctx =
+		crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
+	struct lrw_request_ctx *rctx = skcipher_request_ctx(req);
+	struct skcipher_request *subreq = &rctx->subreq;
+
+	skcipher_request_set_tfm(subreq, ctx->child);
+	skcipher_request_set_callback(subreq, req->base.flags, lrw_crypt_done,
+				      req);
+	/* pass req->iv as IV (will be used by xor_tweak, ECB will ignore it) */
+	skcipher_request_set_crypt(subreq, req->dst, req->dst,
+				   req->cryptlen, req->iv);
+
+	/* calculate first value of T */
+	memcpy(&rctx->t, req->iv, sizeof(rctx->t));
+
+	/* T <- I*Key2 */
+	gf128mul_64k_bbe(&rctx->t, ctx->table);
+}
+
+static int lrw_encrypt(struct skcipher_request *req)
+{
+	struct lrw_request_ctx *rctx = skcipher_request_ctx(req);
+	struct skcipher_request *subreq = &rctx->subreq;
+
+	lrw_init_crypt(req);
+	return lrw_xor_tweak_pre(req) ?:
+		crypto_skcipher_encrypt(subreq) ?:
+		lrw_xor_tweak_post(req);
+}
+
+static int lrw_decrypt(struct skcipher_request *req)
+{
+	struct lrw_request_ctx *rctx = skcipher_request_ctx(req);
+	struct skcipher_request *subreq = &rctx->subreq;
+
+	lrw_init_crypt(req);
+	return lrw_xor_tweak_pre(req) ?:
+		crypto_skcipher_decrypt(subreq) ?:
+		lrw_xor_tweak_post(req);
+}
+
+static int lrw_init_tfm(struct crypto_skcipher *tfm)
+{
+	struct skcipher_instance *inst = skcipher_alg_instance(tfm);
+	struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst);
+	struct lrw_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+	struct crypto_skcipher *cipher;
+
+	cipher = crypto_spawn_skcipher(spawn);
+	if (IS_ERR(cipher))
+		return PTR_ERR(cipher);
+
+	ctx->child = cipher;
+
+	crypto_skcipher_set_reqsize(tfm, crypto_skcipher_reqsize(cipher) +
+					 sizeof(struct lrw_request_ctx));
+
+	return 0;
+}
+
+static void lrw_exit_tfm(struct crypto_skcipher *tfm)
+{
+	struct lrw_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+
+	if (ctx->table)
+		gf128mul_free_64k(ctx->table);
+	crypto_free_skcipher(ctx->child);
+}
+
+static void lrw_free_instance(struct skcipher_instance *inst)
+{
+	crypto_drop_skcipher(skcipher_instance_ctx(inst));
+	kfree(inst);
+}
+
+static int lrw_create(struct crypto_template *tmpl, struct rtattr **tb)
+{
+	struct crypto_skcipher_spawn *spawn;
+	struct skcipher_instance *inst;
+	struct skcipher_alg *alg;
+	const char *cipher_name;
+	char ecb_name[CRYPTO_MAX_ALG_NAME];
+	u32 mask;
+	int err;
+
+	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, &mask);
+	if (err)
+		return err;
+
+	cipher_name = crypto_attr_alg_name(tb[1]);
+	if (IS_ERR(cipher_name))
+		return PTR_ERR(cipher_name);
+
+	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
+	if (!inst)
+		return -ENOMEM;
+
+	spawn = skcipher_instance_ctx(inst);
+
+	err = crypto_grab_skcipher(spawn, skcipher_crypto_instance(inst),
+				   cipher_name, 0, mask);
+	if (err == -ENOENT) {
+		err = -ENAMETOOLONG;
+		if (snprintf(ecb_name, CRYPTO_MAX_ALG_NAME, "ecb(%s)",
+			     cipher_name) >= CRYPTO_MAX_ALG_NAME)
+			goto err_free_inst;
+
+		err = crypto_grab_skcipher(spawn,
+					   skcipher_crypto_instance(inst),
+					   ecb_name, 0, mask);
+	}
+
+	if (err)
+		goto err_free_inst;
+
+	alg = crypto_skcipher_spawn_alg(spawn);
+
+	err = -EINVAL;
+	if (alg->base.cra_blocksize != LRW_BLOCK_SIZE)
+		goto err_free_inst;
+
+	if (crypto_skcipher_alg_ivsize(alg))
+		goto err_free_inst;
+
+	err = crypto_inst_setname(skcipher_crypto_instance(inst), "lrw",
+				  &alg->base);
+	if (err)
+		goto err_free_inst;
+
+	err = -EINVAL;
+	cipher_name = alg->base.cra_name;
+
+	/* Alas we screwed up the naming so we have to mangle the
+	 * cipher name.
+	 */
+	if (!strncmp(cipher_name, "ecb(", 4)) {
+		int len;
+
+		len = strscpy(ecb_name, cipher_name + 4, sizeof(ecb_name));
+		if (len < 2)
+			goto err_free_inst;
+
+		if (ecb_name[len - 1] != ')')
+			goto err_free_inst;
+
+		ecb_name[len - 1] = 0;
+
+		if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+			     "lrw(%s)", ecb_name) >= CRYPTO_MAX_ALG_NAME) {
+			err = -ENAMETOOLONG;
+			goto err_free_inst;
+		}
+	} else
+		goto err_free_inst;
+
+	inst->alg.base.cra_priority = alg->base.cra_priority;
+	inst->alg.base.cra_blocksize = LRW_BLOCK_SIZE;
+	inst->alg.base.cra_alignmask = alg->base.cra_alignmask |
+				       (__alignof__(be128) - 1);
+
+	inst->alg.ivsize = LRW_BLOCK_SIZE;
+	inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg) +
+				LRW_BLOCK_SIZE;
+	inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg) +
+				LRW_BLOCK_SIZE;
+
+	inst->alg.base.cra_ctxsize = sizeof(struct lrw_tfm_ctx);
+
+	inst->alg.init = lrw_init_tfm;
+	inst->alg.exit = lrw_exit_tfm;
+
+	inst->alg.setkey = lrw_setkey;
+	inst->alg.encrypt = lrw_encrypt;
+	inst->alg.decrypt = lrw_decrypt;
+
+	inst->free = lrw_free_instance;
+
+	err = skcipher_register_instance(tmpl, inst);
+	if (err) {
+err_free_inst:
+		lrw_free_instance(inst);
+	}
+	return err;
+}
+
+static struct crypto_template lrw_tmpl = {
+	.name = "lrw",
+	.create = lrw_create,
+	.module = THIS_MODULE,
+};
+
+static int __init lrw_module_init(void)
+{
+	return crypto_register_template(&lrw_tmpl);
+}
+
+static void __exit lrw_module_exit(void)
+{
+	crypto_unregister_template(&lrw_tmpl);
+}
+
+subsys_initcall(lrw_module_init);
+module_exit(lrw_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LRW block cipher mode");
+MODULE_ALIAS_CRYPTO("lrw");
+MODULE_SOFTDEP("pre: ecb");