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authorLinus Torvalds <torvalds@linux-foundation.org>2016-07-26 13:40:17 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-07-26 13:40:17 -0700
commitbbce2ad2d711c12d93145a7bbdf086e73f414bcd (patch)
tree35432a39f68f4c5df44ed38037cbf05adadb923e /crypto/ecdh.c
parent0f776dc377f6c87f4e4d4a5f63602f33fb93b31e (diff)
parent0f95e2ffc58f5d32a90eb1051d17aeebc21cf91d (diff)
Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu: "Here is the crypto update for 4.8: API: - first part of skcipher low-level conversions - add KPP (Key-agreement Protocol Primitives) interface. Algorithms: - fix IPsec/cryptd reordering issues that affects aesni - RSA no longer does explicit leading zero removal - add SHA3 - add DH - add ECDH - improve DRBG performance by not doing CTR by hand Drivers: - add x86 AVX2 multibuffer SHA256/512 - add POWER8 optimised crc32c - add xts support to vmx - add DH support to qat - add RSA support to caam - add Layerscape support to caam - add SEC1 AEAD support to talitos - improve performance by chaining requests in marvell/cesa - add support for Araneus Alea I USB RNG - add support for Broadcom BCM5301 RNG - add support for Amlogic Meson RNG - add support Broadcom NSP SoC RNG" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (180 commits) crypto: vmx - Fix aes_p8_xts_decrypt build failure crypto: vmx - Ignore generated files crypto: vmx - Adding support for XTS crypto: vmx - Adding asm subroutines for XTS crypto: skcipher - add comment for skcipher_alg->base crypto: testmgr - Print akcipher algorithm name crypto: marvell - Fix wrong flag used for GFP in mv_cesa_dma_add_iv_op crypto: nx - off by one bug in nx_of_update_msc() crypto: rsa-pkcs1pad - fix rsa-pkcs1pad request struct crypto: scatterwalk - Inline start/map/done crypto: scatterwalk - Remove unnecessary BUG in scatterwalk_start crypto: scatterwalk - Remove unnecessary advance in scatterwalk_pagedone crypto: scatterwalk - Fix test in scatterwalk_done crypto: api - Optimise away crypto_yield when hard preemption is on crypto: scatterwalk - add no-copy support to copychunks crypto: scatterwalk - Remove scatterwalk_bytes_sglen crypto: omap - Stop using crypto scatterwalk_bytes_sglen crypto: skcipher - Remove top-level givcipher interface crypto: user - Remove crypto_lookup_skcipher call crypto: cts - Convert to skcipher ...
Diffstat (limited to 'crypto/ecdh.c')
-rw-r--r--crypto/ecdh.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/crypto/ecdh.c b/crypto/ecdh.c
new file mode 100644
index 000000000000..3de289806d67
--- /dev/null
+++ b/crypto/ecdh.c
@@ -0,0 +1,151 @@
+/* ECDH key-agreement protocol
+ *
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvator Benedetto <salvatore.benedetto@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <crypto/internal/kpp.h>
+#include <crypto/kpp.h>
+#include <crypto/ecdh.h>
+#include <linux/scatterlist.h>
+#include "ecc.h"
+
+struct ecdh_ctx {
+ unsigned int curve_id;
+ unsigned int ndigits;
+ u64 private_key[ECC_MAX_DIGITS];
+ u64 public_key[2 * ECC_MAX_DIGITS];
+ u64 shared_secret[ECC_MAX_DIGITS];
+};
+
+static inline struct ecdh_ctx *ecdh_get_ctx(struct crypto_kpp *tfm)
+{
+ return kpp_tfm_ctx(tfm);
+}
+
+static unsigned int ecdh_supported_curve(unsigned int curve_id)
+{
+ switch (curve_id) {
+ case ECC_CURVE_NIST_P192: return 3;
+ case ECC_CURVE_NIST_P256: return 4;
+ default: return 0;
+ }
+}
+
+static int ecdh_set_secret(struct crypto_kpp *tfm, void *buf, unsigned int len)
+{
+ struct ecdh_ctx *ctx = ecdh_get_ctx(tfm);
+ struct ecdh params;
+ unsigned int ndigits;
+
+ if (crypto_ecdh_decode_key(buf, len, &params) < 0)
+ return -EINVAL;
+
+ ndigits = ecdh_supported_curve(params.curve_id);
+ if (!ndigits)
+ return -EINVAL;
+
+ ctx->curve_id = params.curve_id;
+ ctx->ndigits = ndigits;
+
+ if (ecc_is_key_valid(ctx->curve_id, ctx->ndigits,
+ (const u8 *)params.key, params.key_size) < 0)
+ return -EINVAL;
+
+ memcpy(ctx->private_key, params.key, params.key_size);
+
+ return 0;
+}
+
+static int ecdh_compute_value(struct kpp_request *req)
+{
+ int ret = 0;
+ struct crypto_kpp *tfm = crypto_kpp_reqtfm(req);
+ struct ecdh_ctx *ctx = ecdh_get_ctx(tfm);
+ size_t copied, nbytes;
+ void *buf;
+
+ nbytes = ctx->ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+
+ if (req->src) {
+ copied = sg_copy_to_buffer(req->src, 1, ctx->public_key,
+ 2 * nbytes);
+ if (copied != 2 * nbytes)
+ return -EINVAL;
+
+ ret = crypto_ecdh_shared_secret(ctx->curve_id, ctx->ndigits,
+ (const u8 *)ctx->private_key, nbytes,
+ (const u8 *)ctx->public_key, 2 * nbytes,
+ (u8 *)ctx->shared_secret, nbytes);
+
+ buf = ctx->shared_secret;
+ } else {
+ ret = ecdh_make_pub_key(ctx->curve_id, ctx->ndigits,
+ (const u8 *)ctx->private_key, nbytes,
+ (u8 *)ctx->public_key,
+ sizeof(ctx->public_key));
+ buf = ctx->public_key;
+ /* Public part is a point thus it has both coordinates */
+ nbytes *= 2;
+ }
+
+ if (ret < 0)
+ return ret;
+
+ copied = sg_copy_from_buffer(req->dst, 1, buf, nbytes);
+ if (copied != nbytes)
+ return -EINVAL;
+
+ return ret;
+}
+
+static int ecdh_max_size(struct crypto_kpp *tfm)
+{
+ struct ecdh_ctx *ctx = ecdh_get_ctx(tfm);
+ int nbytes = ctx->ndigits << ECC_DIGITS_TO_BYTES_SHIFT;
+
+ /* Public key is made of two coordinates */
+ return 2 * nbytes;
+}
+
+static void no_exit_tfm(struct crypto_kpp *tfm)
+{
+ return;
+}
+
+static struct kpp_alg ecdh = {
+ .set_secret = ecdh_set_secret,
+ .generate_public_key = ecdh_compute_value,
+ .compute_shared_secret = ecdh_compute_value,
+ .max_size = ecdh_max_size,
+ .exit = no_exit_tfm,
+ .base = {
+ .cra_name = "ecdh",
+ .cra_driver_name = "ecdh-generic",
+ .cra_priority = 100,
+ .cra_module = THIS_MODULE,
+ .cra_ctxsize = sizeof(struct ecdh_ctx),
+ },
+};
+
+static int ecdh_init(void)
+{
+ return crypto_register_kpp(&ecdh);
+}
+
+static void ecdh_exit(void)
+{
+ crypto_unregister_kpp(&ecdh);
+}
+
+module_init(ecdh_init);
+module_exit(ecdh_exit);
+MODULE_ALIAS_CRYPTO("ecdh");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("ECDH generic algorithm");