summaryrefslogtreecommitdiffstats
path: root/crypto/ecdh_helper.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2016-07-26 22:40:17 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2016-07-26 22:40:17 +0200
commitbbce2ad2d711c12d93145a7bbdf086e73f414bcd (patch)
tree35432a39f68f4c5df44ed38037cbf05adadb923e /crypto/ecdh_helper.c
parentMerge tag 'docs-for-linus' of git://git.lwn.net/linux (diff)
parentMerge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 (diff)
downloadlinux-bbce2ad2d711c12d93145a7bbdf086e73f414bcd.tar.xz
linux-bbce2ad2d711c12d93145a7bbdf086e73f414bcd.zip
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_helper.c')
-rw-r--r--crypto/ecdh_helper.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/crypto/ecdh_helper.c b/crypto/ecdh_helper.c
new file mode 100644
index 000000000000..3cd8a2414e60
--- /dev/null
+++ b/crypto/ecdh_helper.c
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvatore 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/kernel.h>
+#include <linux/export.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <crypto/ecdh.h>
+#include <crypto/kpp.h>
+
+#define ECDH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 2 * sizeof(short))
+
+static inline u8 *ecdh_pack_data(void *dst, const void *src, size_t sz)
+{
+ memcpy(dst, src, sz);
+ return dst + sz;
+}
+
+static inline const u8 *ecdh_unpack_data(void *dst, const void *src, size_t sz)
+{
+ memcpy(dst, src, sz);
+ return src + sz;
+}
+
+int crypto_ecdh_key_len(const struct ecdh *params)
+{
+ return ECDH_KPP_SECRET_MIN_SIZE + params->key_size;
+}
+EXPORT_SYMBOL_GPL(crypto_ecdh_key_len);
+
+int crypto_ecdh_encode_key(char *buf, unsigned int len,
+ const struct ecdh *params)
+{
+ u8 *ptr = buf;
+ struct kpp_secret secret = {
+ .type = CRYPTO_KPP_SECRET_TYPE_ECDH,
+ .len = len
+ };
+
+ if (unlikely(!buf))
+ return -EINVAL;
+
+ if (len != crypto_ecdh_key_len(params))
+ return -EINVAL;
+
+ ptr = ecdh_pack_data(ptr, &secret, sizeof(secret));
+ ptr = ecdh_pack_data(ptr, &params->curve_id, sizeof(params->curve_id));
+ ptr = ecdh_pack_data(ptr, &params->key_size, sizeof(params->key_size));
+ ecdh_pack_data(ptr, params->key, params->key_size);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(crypto_ecdh_encode_key);
+
+int crypto_ecdh_decode_key(const char *buf, unsigned int len,
+ struct ecdh *params)
+{
+ const u8 *ptr = buf;
+ struct kpp_secret secret;
+
+ if (unlikely(!buf || len < ECDH_KPP_SECRET_MIN_SIZE))
+ return -EINVAL;
+
+ ptr = ecdh_unpack_data(&secret, ptr, sizeof(secret));
+ if (secret.type != CRYPTO_KPP_SECRET_TYPE_ECDH)
+ return -EINVAL;
+
+ ptr = ecdh_unpack_data(&params->curve_id, ptr, sizeof(params->curve_id));
+ ptr = ecdh_unpack_data(&params->key_size, ptr, sizeof(params->key_size));
+ if (secret.len != crypto_ecdh_key_len(params))
+ return -EINVAL;
+
+ /* Don't allocate memory. Set pointer to data
+ * within the given buffer
+ */
+ params->key = (void *)ptr;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(crypto_ecdh_decode_key);