From 1b908a36e24de2908d1bb585d43bf23b85656ec6 Mon Sep 17 00:00:00 2001
From: Petr Tesarik <ptesarik@suse.cz>
Date: Sep 08 2020 16:34:34 +0000
Subject: crypto: ecc - SP800-56A rev 3 local public key validation

(bsc#1175718).

---

diff --git a/patches.suse/crypto-ecc-sp800-56a-rev-3-local-public-key-validation b/patches.suse/crypto-ecc-sp800-56a-rev-3-local-public-key-validation
new file mode 100644
index 0000000..19d7ab6
--- /dev/null
+++ b/patches.suse/crypto-ecc-sp800-56a-rev-3-local-public-key-validation
@@ -0,0 +1,83 @@
+From: =?UTF-8?q?Stephan=20M=C3=BCller?= <smueller@chronox.de>
+Date: Mon, 20 Jul 2020 19:09:23 +0200
+Subject: crypto: ecc - SP800-56A rev 3 local public key validation
+Git-commit: 6914dd53eb7af7cbc66edf7992d600b1e952c40d
+Patch-mainline: v5.9-rc1
+References: bsc#1175718
+
+After the generation of a local public key, SP800-56A rev 3 section
+5.6.2.1.3 mandates a validation of that key with a full validation
+compliant to section 5.6.2.3.3.
+
+Only if the full validation passes, the key is allowed to be used.
+
+The patch adds the full key validation compliant to 5.6.2.3.3 and
+performs the required check on the generated public key.
+
+Signed-off-by: Stephan Mueller <smueller@chronox.de>
+Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
+[ ptesarik: The export is needed only to share the routines with ecrdsa.
+  SLE15 does not have the ecrdsa module, so the added function should be
+  local to crypto/ecc.c. ]
+Signed-off-by: Petr Tesarik <ptesarik@suse.com>
+---
+ crypto/ecc.c |   34 +++++++++++++++++++++++++++++++++-
+ 1 file changed, 33 insertions(+), 1 deletion(-)
+
+--- a/crypto/ecc.c
++++ b/crypto/ecc.c
+@@ -42,6 +42,9 @@ typedef struct {
+ 	u64 m_high;
+ } uint128_t;
+ 
++static int ecc_is_pubkey_valid_full(const struct ecc_curve *curve,
++				    struct ecc_point *pk);
++
+ static inline const struct ecc_curve *ecc_get_curve(unsigned int curve_id)
+ {
+ 	switch (curve_id) {
+@@ -1404,7 +1407,9 @@ int ecc_make_pub_key(unsigned int curve_
+ 	}
+ 
+ 	ecc_point_mult(pk, &curve->g, priv, NULL, curve, ndigits);
+-	if (ecc_point_is_zero(pk)) {
++
++	/* SP800-56A rev 3 5.6.2.1.3 key check */
++	if (ecc_is_pubkey_valid_full(curve, pk)) {
+ 		ret = -EAGAIN;
+ 		goto err_free_point;
+ 	}
+@@ -1452,6 +1457,33 @@ int ecc_is_pubkey_valid_partial(const st
+ }
+ EXPORT_SYMBOL(ecc_is_pubkey_valid_partial);
+ 
++/* SP800-56A section 5.6.2.3.3 full verification */
++static int ecc_is_pubkey_valid_full(const struct ecc_curve *curve,
++				    struct ecc_point *pk)
++{
++	struct ecc_point *nQ;
++
++	/* Checks 1 through 3 */
++	int ret = ecc_is_pubkey_valid_partial(curve, pk);
++
++	if (ret)
++		return ret;
++
++	/* Check 4: Verify that nQ is the zero point. */
++	nQ = ecc_alloc_point(pk->ndigits);
++	if (!nQ)
++		return -ENOMEM;
++
++	ecc_point_mult(nQ, pk, curve->n, NULL, curve, pk->ndigits);
++	if (!ecc_point_is_zero(nQ))
++		ret = -EINVAL;
++
++	ecc_free_point(nQ);
++
++	return ret;
++}
++EXPORT_SYMBOL(ecc_is_pubkey_valid_full);
++
+ int crypto_ecdh_shared_secret(unsigned int curve_id, unsigned int ndigits,
+ 			      const u64 *private_key, const u64 *public_key,
+ 			      u64 *secret)
diff --git a/series.conf b/series.conf
index abc5480..880281c 100644
--- a/series.conf
+++ b/series.conf
@@ -14027,6 +14027,7 @@
 	patches.suse/lib-mpi-add-mpi_sub_ui
 	patches.suse/crypto-dh-check-validity-of-z-before-export
 	patches.suse/crypto-dh-sp800-56a-rev-3-local-public-key-validation
+	patches.suse/crypto-ecc-sp800-56a-rev-3-local-public-key-validation
 	patches.suse/mtd-properly-check-all-write-ioctls-for-permissions.patch
 	patches.suse/0001-block-improve-discard-bio-alignment-in-__blkdev_issu.patch
 	patches.suse/sched-cputime-Improve-cputime_adjust.patch