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!6 fix CVE-2021-20305

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From: @haochenstar
Reviewed-by: @overweight
Signed-off-by: @overweight
This commit is contained in:
openeuler-ci-bot 2021-04-20 09:53:44 +08:00 committed by Gitee
commit 27d49bc246
8 changed files with 563 additions and 1 deletions
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From a63893791280d441c713293491da97c79c0950fe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Niels=20M=C3=B6ller?= <nisse@lysator.liu.se>
Date: Thu, 11 Mar 2021 19:37:41 +0100
Subject: [PATCH] New functions ecc_mod_mul_canonical and
ecc_mod_sqr_canonical.
* ecc-mod-arith.c (ecc_mod_mul_canonical, ecc_mod_sqr_canonical):
New functions.
* ecc-internal.h: Declare and document new functions.
* curve448-eh-to-x.c (curve448_eh_to_x): Use ecc_mod_sqr_canonical.
* curve25519-eh-to-x.c (curve25519_eh_to_x): Use ecc_mod_mul_canonical.
* ecc-eh-to-a.c (ecc_eh_to_a): Likewise.
* ecc-j-to-a.c (ecc_j_to_a): Likewise.
* ecc-mul-m.c (ecc_mul_m): Likewise.
(cherry picked from commit 2bf497ba4d6acc6f352bca015837fad33008565c)
---
ChangeLog | 11 +++++++++++
curve25519-eh-to-x.c | 6 +-----
curve448-eh-to-x.c | 5 +----
ecc-eh-to-a.c | 12 ++----------
ecc-internal.h | 15 +++++++++++++++
ecc-j-to-a.c | 15 +++------------
ecc-mod-arith.c | 24 ++++++++++++++++++++++++
ecc-mul-m.c | 6 ++----
8 files changed, 59 insertions(+), 35 deletions(-)
#diff --git a/ChangeLog b/ChangeLog
#index fd138d82..5cc5c188 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,3 +1,14 @@
#+2021-03-11 Niels Möller <nisse@lysator.liu.se>
#+
#+ * ecc-mod-arith.c (ecc_mod_mul_canonical, ecc_mod_sqr_canonical):
#+ New functions.
#+ * ecc-internal.h: Declare and document new functions.
#+ * curve448-eh-to-x.c (curve448_eh_to_x): Use ecc_mod_sqr_canonical.
#+ * curve25519-eh-to-x.c (curve25519_eh_to_x): Use ecc_mod_mul_canonical.
#+ * ecc-eh-to-a.c (ecc_eh_to_a): Likewise.
#+ * ecc-j-to-a.c (ecc_j_to_a): Likewise.
#+ * ecc-mul-m.c (ecc_mul_m): Likewise.
#+
# 2021-02-17 Niels Möller <nisse@lysator.liu.se>
#
# * Released Nettle-3.7.1.
--- a/curve25519-eh-to-x.c
+++ b/curve25519-eh-to-x.c
@@ -53,7 +53,6 @@ curve25519_eh_to_x (mp_limb_t *xp, const
#define t2 (scratch + 2*ecc->p.size)
const struct ecc_curve *ecc = &_nettle_curve25519;
- mp_limb_t cy;
/* If u = U/W and v = V/W are the coordiantes of the point on the
Edwards curve we get the curve25519 x coordinate as
@@ -69,10 +68,7 @@ curve25519_eh_to_x (mp_limb_t *xp, const
ecc->p.invert (&ecc->p, t1, t0, t2 + ecc->p.size);
ecc_mod_add (&ecc->p, t0, wp, vp);
- ecc_mod_mul (&ecc->p, t2, t0, t1);
-
- cy = mpn_sub_n (xp, t2, ecc->p.m, ecc->p.size);
- cnd_copy (cy, xp, t2, ecc->p.size);
+ ecc_mod_mul_canonical (&ecc->p, xp, t0, t1, t2);
#undef vp
#undef wp
#undef t0
--- a/curve448-eh-to-x.c
+++ b/curve448-eh-to-x.c
@@ -52,7 +52,6 @@ curve448_eh_to_x (mp_limb_t *xp, const m
#define t2 (scratch + 2*ecc->p.size)
const struct ecc_curve *ecc = &_nettle_curve448;
- mp_limb_t cy;
/* If u = U/W and v = V/W are the coordinates of the point on
edwards448 we get the curve448 x coordinate as
@@ -62,10 +61,8 @@ curve448_eh_to_x (mp_limb_t *xp, const m
/* Needs a total of 9*size storage. */
ecc->p.invert (&ecc->p, t0, p, t1 + ecc->p.size);
ecc_mod_mul (&ecc->p, t1, t0, vp);
- ecc_mod_mul (&ecc->p, t2, t1, t1);
+ ecc_mod_mul_canonical (&ecc->p, xp, t1, t1, t2);
- cy = mpn_sub_n (xp, t2, ecc->p.m, ecc->p.size);
- cnd_copy (cy, xp, t2, ecc->p.size);
#undef vp
#undef t0
#undef t1
--- a/ecc-eh-to-a.c
+++ b/ecc-eh-to-a.c
@@ -54,18 +54,11 @@ ecc_eh_to_a (const struct ecc_curve *ecc
#define yp (p + ecc->p.size)
#define zp (p + 2*ecc->p.size)
- mp_limb_t cy;
-
assert(op == 0);
/* Needs 2*size + scratch for the invert call. */
ecc->p.invert (&ecc->p, izp, zp, tp + ecc->p.size);
- ecc_mod_mul (&ecc->p, tp, xp, izp);
- cy = mpn_sub_n (r, tp, ecc->p.m, ecc->p.size);
- cnd_copy (cy, r, tp, ecc->p.size);
-
- ecc_mod_mul (&ecc->p, tp, yp, izp);
- cy = mpn_sub_n (r + ecc->p.size, tp, ecc->p.m, ecc->p.size);
- cnd_copy (cy, r + ecc->p.size, tp, ecc->p.size);
+ ecc_mod_mul_canonical (&ecc->p, r, xp, izp, tp);
+ ecc_mod_mul_canonical (&ecc->p, r + ecc->p.size, yp, izp, tp);
}
--- a/ecc-internal.h
+++ b/ecc-internal.h
@@ -49,6 +49,8 @@
#define ecc_mod_submul_1 _nettle_ecc_mod_submul_1
#define ecc_mod_mul _nettle_ecc_mod_mul
#define ecc_mod_sqr _nettle_ecc_mod_sqr
+#define ecc_mod_mul_canonical _nettle_ecc_mod_mul_canonical
+#define ecc_mod_sqr_canonical _nettle_ecc_mod_sqr_canonical
#define ecc_mod_random _nettle_ecc_mod_random
#define ecc_mod _nettle_ecc_mod
#define ecc_mod_inv _nettle_ecc_mod_inv
@@ -256,6 +258,19 @@ void
ecc_mod_sqr (const struct ecc_modulo *m, mp_limb_t *rp,
const mp_limb_t *ap);
+/* These mul and sqr functions produce a canonical result, 0 <= R < M.
+ Requirements on input and output areas are similar to the above
+ functions, except that it is *not* allowed to pass rp = rp +
+ m->size.
+ */
+void
+ecc_mod_mul_canonical (const struct ecc_modulo *m, mp_limb_t *rp,
+ const mp_limb_t *ap, const mp_limb_t *bp, mp_limb_t *tp);
+
+void
+ecc_mod_sqr_canonical (const struct ecc_modulo *m, mp_limb_t *rp,
+ const mp_limb_t *ap, mp_limb_t *tp);
+
/* mod q operations. */
void
ecc_mod_random (const struct ecc_modulo *m, mp_limb_t *xp,
--- a/ecc-j-to-a.c
+++ b/ecc-j-to-a.c
@@ -51,8 +51,6 @@ ecc_j_to_a (const struct ecc_curve *ecc,
#define izBp (scratch + 3*ecc->p.size)
#define tp scratch
- mp_limb_t cy;
-
if (ecc->use_redc)
{
/* Set v = (r_z / B^2)^-1,
@@ -86,17 +84,13 @@ ecc_j_to_a (const struct ecc_curve *ecc,
ecc_mod_sqr (&ecc->p, iz2p, izp);
}
- ecc_mod_mul (&ecc->p, iz3p, iz2p, p);
- /* ecc_mod (and ecc_mod_mul) may return a value up to 2p - 1, so
- do a conditional subtraction. */
- cy = mpn_sub_n (r, iz3p, ecc->p.m, ecc->p.size);
- cnd_copy (cy, r, iz3p, ecc->p.size);
-
+ ecc_mod_mul_canonical (&ecc->p, r, iz2p, p, iz3p);
if (op)
{
/* Skip y coordinate */
if (op > 1)
{
+ mp_limb_t cy;
/* Also reduce the x coordinate mod ecc->q. It should
already be < 2*ecc->q, so one subtraction should
suffice. */
@@ -106,10 +100,7 @@ ecc_j_to_a (const struct ecc_curve *ecc,
return;
}
ecc_mod_mul (&ecc->p, iz3p, iz2p, izp);
- ecc_mod_mul (&ecc->p, tp, iz3p, p + ecc->p.size);
- /* And a similar subtraction. */
- cy = mpn_sub_n (r + ecc->p.size, tp, ecc->p.m, ecc->p.size);
- cnd_copy (cy, r + ecc->p.size, tp, ecc->p.size);
+ ecc_mod_mul_canonical (&ecc->p, r + ecc->p.size, iz3p, p + ecc->p.size, iz3p);
#undef izp
#undef up
--- a/ecc-mod-arith.c
+++ b/ecc-mod-arith.c
@@ -119,6 +119,30 @@ ecc_mod_mul (const struct ecc_modulo *m,
}
void
+ecc_mod_mul_canonical (const struct ecc_modulo *m, mp_limb_t *rp,
+ const mp_limb_t *ap, const mp_limb_t *bp, mp_limb_t *tp)
+{
+ mp_limb_t cy;
+ mpn_mul_n (tp + m->size, ap, bp, m->size);
+ m->reduce (m, tp + m->size);
+
+ cy = mpn_sub_n (rp, tp + m->size, m->m, m->size);
+ cnd_copy (cy, rp, tp + m->size, m->size);
+}
+
+void
+ecc_mod_sqr_canonical (const struct ecc_modulo *m, mp_limb_t *rp,
+ const mp_limb_t *ap, mp_limb_t *tp)
+{
+ mp_limb_t cy;
+ mpn_sqr (tp + m->size, ap, m->size);
+ m->reduce (m, tp + m->size);
+
+ cy = mpn_sub_n (rp, tp + m->size, m->m, m->size);
+ cnd_copy (cy, rp, tp + m->size, m->size);
+}
+
+void
ecc_mod_sqr (const struct ecc_modulo *m, mp_limb_t *rp,
const mp_limb_t *ap)
{

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From 971bed6ab4b27014eb23085e8176917e1a096fd5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Niels=20M=C3=B6ller?= <nisse@lysator.liu.se>
Date: Sat, 13 Mar 2021 17:26:37 +0100
Subject: [PATCH] Use ecc_mod_mul_canonical for point comparison.
* eddsa-verify.c (equal_h): Use ecc_mod_mul_canonical.
(cherry picked from commit 5b7608fde3a6d2ab82bffb35db1e4e330927c906)
---
ChangeLog | 4 ++++
eddsa-verify.c | 9 ++-------
2 files changed, 6 insertions(+), 7 deletions(-)
#diff --git a/ChangeLog b/ChangeLog
#index 5cc5c188..2a9217a6 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,3 +1,7 @@
#+2021-03-13 Niels Möller <nisse@lysator.liu.se>
#+
#+ * eddsa-verify.c (equal_h): Use ecc_mod_mul_canonical.
#+
# 2021-03-11 Niels Möller <nisse@lysator.liu.se>
#
# * ecc-mod-arith.c (ecc_mod_mul_canonical, ecc_mod_sqr_canonical):
--- a/eddsa-verify.c
+++ b/eddsa-verify.c
@@ -53,13 +53,8 @@ equal_h (const struct ecc_modulo *p,
#define t0 scratch
#define t1 (scratch + p->size)
- ecc_mod_mul (p, t0, x1, z2);
- if (mpn_cmp (t0, p->m, p->size) >= 0)
- mpn_sub_n (t0, t0, p->m, p->size);
-
- ecc_mod_mul (p, t1, x2, z1);
- if (mpn_cmp (t1, p->m, p->size) >= 0)
- mpn_sub_n (t1, t1, p->m, p->size);
+ ecc_mod_mul_canonical (p, t0, x1, z2, t0);
+ ecc_mod_mul_canonical (p, t1, x2, z1, t1);
return mpn_cmp (t0, t1, p->size) == 0;

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From 74ee0e82b6891e090f20723750faeb19064e31b2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Niels=20M=C3=B6ller?= <nisse@lysator.liu.se>
Date: Sat, 13 Mar 2021 15:19:19 +0100
Subject: [PATCH] Fix bug in ecc_ecdsa_verify.
* ecc-ecdsa-verify.c (ecc_ecdsa_verify): Use ecc_mod_mul_canonical
to compute the scalars used for ecc multiplication.
* testsuite/ecdsa-verify-test.c (test_main): Add test case that
triggers an assert on 64-bit platforms, without above fix.
* testsuite/ecdsa-sign-test.c (test_main): Test case generating
the same signature.
(cherry picked from commit 2397757b3f95fcae1e2d3011bf99ca5b5438378f)
---
ChangeLog | 10 +++++++++-
ecc-ecdsa-verify.c | 4 ++--
testsuite/ecdsa-sign-test.c | 13 +++++++++++++
testsuite/ecdsa-verify-test.c | 20 ++++++++++++++++++++
4 files changed, 44 insertions(+), 3 deletions(-)
#diff --git a/ChangeLog b/ChangeLog
#index 2a9217a6..63848f53 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,7 +1,15 @@
# 2021-03-13 Niels Möller <nisse@lysator.liu.se>
#
#- * eddsa-verify.c (equal_h): Use ecc_mod_mul_canonical.
#+ * ecc-ecdsa-verify.c (ecc_ecdsa_verify): Use ecc_mod_mul_canonical
#+ to compute the scalars used for ecc multiplication.
#+ * testsuite/ecdsa-verify-test.c (test_main): Add test case that
#+ triggers an assert on 64-bit platforms, without above fix.
#+ * testsuite/ecdsa-sign-test.c (test_main): Test case generating
#+ the same signature.
#+
#+2021-03-13 Niels Möller <nisse@lysator.liu.se>
#
#+ * eddsa-verify.c (equal_h): Use ecc_mod_mul_canonical.
# 2021-03-11 Niels Möller <nisse@lysator.liu.se>
#
# * ecc-mod-arith.c (ecc_mod_mul_canonical, ecc_mod_sqr_canonical):
--- a/ecc-ecdsa-verify.c
+++ b/ecc-ecdsa-verify.c
@@ -102,10 +102,10 @@ ecc_ecdsa_verify (const struct ecc_curve
/* u1 = h / s, P1 = u1 * G */
ecc_hash (&ecc->q, hp, length, digest);
- ecc_mod_mul (&ecc->q, u1, hp, sinv);
+ ecc_mod_mul_canonical (&ecc->q, u1, hp, sinv, u1);
/* u2 = r / s, P2 = u2 * Y */
- ecc_mod_mul (&ecc->q, u2, rp, sinv);
+ ecc_mod_mul_canonical (&ecc->q, u2, rp, sinv, u2);
/* Total storage: 5*ecc->p.size + ecc->mul_itch */
ecc->mul (ecc, P2, u2, pp, u2 + ecc->p.size);
--- a/testsuite/ecdsa-sign-test.c
+++ b/testsuite/ecdsa-sign-test.c
@@ -58,6 +58,19 @@ test_ecdsa (const struct ecc_curve *ecc,
void
test_main (void)
{
+ /* Producing the signature for corresponding test in
+ ecdsa-verify-test.c, with special u1 and u2. */
+ test_ecdsa (&_nettle_secp_224r1,
+ "99b5b787484def12894ca507058b3bf5"
+ "43d72d82fa7721d2e805e5e6",
+ "2",
+ SHEX("cdb887ac805a3b42e22d224c85482053"
+ "16c755d4a736bb2032c92553"),
+ "706a46dc76dcb76798e60e6d89474788"
+ "d16dc18032d268fd1a704fa6", /* r */
+ "3a41e1423b1853e8aa89747b1f987364"
+ "44705d6d6d8371ea1f578f2e"); /* s */
+
/* Test cases for the smaller groups, verified with a
proof-of-concept implementation done for Yubico AB. */
/* From RFC 4754 */
--- a/testsuite/ecdsa-verify-test.c
+++ b/testsuite/ecdsa-verify-test.c
@@ -81,6 +81,26 @@ test_ecdsa (const struct ecc_curve *ecc,
void
test_main (void)
{
+ /* Corresponds to nonce k = 2 and private key z =
+ 0x99b5b787484def12894ca507058b3bf543d72d82fa7721d2e805e5e6. z and
+ hash are chosen so that intermediate scalars in the verify
+ equations are u1 = 0x6b245680e700, u2 =
+ 259da6542d4ba7d21ad916c3bd57f811. These values require canonical
+ reduction of the scalars. Bug caused by missing canonical
+ reduction reported by Guido Vranken. */
+ test_ecdsa (&_nettle_secp_224r1,
+ "9e7e6cc6b1bdfa8ee039b66ad85e5490"
+ "7be706a900a3cba1c8fdd014", /* x */
+ "74855db3f7c1b4097ae095745fc915e3"
+ "8a79d2a1de28f282eafb22ba", /* y */
+
+ SHEX("cdb887ac805a3b42e22d224c85482053"
+ "16c755d4a736bb2032c92553"),
+ "706a46dc76dcb76798e60e6d89474788"
+ "d16dc18032d268fd1a704fa6", /* r */
+ "3a41e1423b1853e8aa89747b1f987364"
+ "44705d6d6d8371ea1f578f2e"); /* s */
+
/* From RFC 4754 */
test_ecdsa (&_nettle_secp_256r1,
"2442A5CC 0ECD015F A3CA31DC 8E2BBC70"

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From 51f643eee00e2caa65c8a2f5857f49acdf3ef1ce Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Niels=20M=C3=B6ller?= <nisse@lysator.liu.se>
Date: Sat, 13 Mar 2021 16:27:50 +0100
Subject: [PATCH] Ensure ecdsa_sign output is canonically reduced.
* ecc-ecdsa-sign.c (ecc_ecdsa_sign): Ensure s output is reduced to
canonical range.
(cherry picked from commit c24b36160dc5303f7541dd9da1429c4046f27398)
---
ChangeLog | 3 +++
ecc-ecdsa-sign.c | 3 +--
2 files changed, 4 insertions(+), 2 deletions(-)
#diff --git a/ChangeLog b/ChangeLog
#index 63848f53..fb2d7f66 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,5 +1,8 @@
# 2021-03-13 Niels Möller <nisse@lysator.liu.se>
#
#+ * ecc-ecdsa-sign.c (ecc_ecdsa_sign): Ensure s output is reduced to
#+ canonical range.
#+
# * ecc-ecdsa-verify.c (ecc_ecdsa_verify): Use ecc_mod_mul_canonical
# to compute the scalars used for ecc multiplication.
# * testsuite/ecdsa-verify-test.c (test_main): Add test case that
--- a/ecc-ecdsa-sign.c
+++ b/ecc-ecdsa-sign.c
@@ -90,9 +90,8 @@ ecc_ecdsa_sign (const struct ecc_curve *
ecc_mod_mul (&ecc->q, tp, zp, rp);
ecc_mod_add (&ecc->q, hp, hp, tp);
- ecc_mod_mul (&ecc->q, tp, hp, kinv);
+ ecc_mod_mul_canonical (&ecc->q, sp, hp, kinv, tp);
- mpn_copyi (sp, tp, ecc->p.size);
#undef P
#undef hp
#undef kinv

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From 401c8d53d8a8cf1e79980e62bda3f946f8e07c14 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Niels=20M=C3=B6ller?= <nisse@lysator.liu.se>
Date: Sat, 13 Mar 2021 16:29:50 +0100
Subject: [PATCH] Analogous fix to ecc_gostdsa_verify.
* ecc-gostdsa-verify.c (ecc_gostdsa_verify): Use ecc_mod_mul_canonical
to compute the scalars used for ecc multiplication.
(cherry picked from commit fbaefb64b90cb45b7075a0ed72a92f2a1fbcd2ab)
---
ChangeLog | 3 +++
ecc-gostdsa-verify.c | 6 +++---
2 files changed, 6 insertions(+), 3 deletions(-)
#diff --git a/ChangeLog b/ChangeLog
#index fb2d7f66..5f8a22c2 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,5 +1,8 @@
# 2021-03-13 Niels Möller <nisse@lysator.liu.se>
#
#+ * ecc-gostdsa-verify.c (ecc_gostdsa_verify): Use ecc_mod_mul_canonical
#+ to compute the scalars used for ecc multiplication.
#+
# * ecc-ecdsa-sign.c (ecc_ecdsa_sign): Ensure s output is reduced to
# canonical range.
#
--- a/ecc-gostdsa-verify.c
+++ b/ecc-gostdsa-verify.c
@@ -102,11 +102,11 @@ ecc_gostdsa_verify (const struct ecc_cur
ecc->q.invert (&ecc->q, vp, hp, vp + 2*ecc->p.size);
/* z1 = s / h, P1 = z1 * G */
- ecc_mod_mul (&ecc->q, z1, sp, vp);
+ ecc_mod_mul_canonical (&ecc->q, z1, sp, vp, z1);
/* z2 = - r / h, P2 = z2 * Y */
- ecc_mod_mul (&ecc->q, z2, rp, vp);
- mpn_sub_n (z2, ecc->q.m, z2, ecc->p.size);
+ mpn_sub_n (hp, ecc->q.m, rp, ecc->p.size);
+ ecc_mod_mul_canonical (&ecc->q, z2, hp, vp, z2);
/* Total storage: 5*ecc->p.size + ecc->mul_itch */
ecc->mul (ecc, P2, z2, pp, z2 + ecc->p.size);

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From ae3801a0e5cce276c270973214385c86048d5f7b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Niels=20M=C3=B6ller?= <nisse@lysator.liu.se>
Date: Sat, 13 Mar 2021 16:42:21 +0100
Subject: [PATCH] Similar fix for eddsa.
* eddsa-hash.c (_eddsa_hash): Ensure result is canonically
reduced. Two of the three call sites need that.
(cherry picked from commit d9b564e4b3b3a5691afb9328c7342b3f7ca64288)
---
ChangeLog | 3 +++
eddsa-hash.c | 10 +++++++---
2 files changed, 10 insertions(+), 3 deletions(-)
#diff --git a/ChangeLog b/ChangeLog
#index 5f8a22c2..ce330831 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,5 +1,8 @@
# 2021-03-13 Niels Möller <nisse@lysator.liu.se>
#
#+ * eddsa-hash.c (_eddsa_hash): Ensure result is canonically
#+ reduced. Two of the three call sites need that.
#+
# * ecc-gostdsa-verify.c (ecc_gostdsa_verify): Use ecc_mod_mul_canonical
# to compute the scalars used for ecc multiplication.
#
--- a/eddsa-hash.c
+++ b/eddsa-hash.c
@@ -44,13 +44,14 @@
#include "ecc-internal.h"
#include "nettle-internal.h"
-/* Convert hash digest to integer, and reduce modulo q, to m->size
- limbs. Needs space for 2*m->size + 1 at rp. */
+/* Convert hash digest to integer, and reduce canonically modulo q.
+ Needs space for 2*m->size + 1 at rp. */
void
_eddsa_hash (const struct ecc_modulo *m,
mp_limb_t *rp, size_t digest_size, const uint8_t *digest)
{
mp_size_t nlimbs = (8*digest_size + GMP_NUMB_BITS - 1) / GMP_NUMB_BITS;
+ mp_limb_t cy;
mpn_set_base256_le (rp, nlimbs, digest, digest_size);
@@ -75,4 +76,8 @@ _eddsa_hash (const struct ecc_modulo *m,
assert (hi == 0);
}
m->mod (m, rp);
+ mpn_copyi (rp + m->size, rp, m->size);
+ /* Ensure canonical reduction. */
+ cy = mpn_sub_n (rp, rp + m->size, m->m, m->size);
+ cnd_copy (cy, rp, rp + m->size, m->size);
}

38
backport-0007-CVE-2021-20305.patch Normal file
View File

@ -0,0 +1,38 @@
From 63f222c60b03470c0005aa9bc4296fbf585f68b9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Niels=20M=C3=B6ller?= <nisse@lysator.liu.se>
Date: Sat, 13 Mar 2021 16:45:34 +0100
Subject: [PATCH] Fix canonical reduction in gostdsa_vko.
* gostdsa-vko.c (gostdsa_vko): Use ecc_mod_mul_canonical to
compute the scalar used for ecc multiplication.
(cherry picked from commit b30e0ca6d2b41579a5b6a010fc54065d790e8d55)
---
ChangeLog | 3 +++
gostdsa-vko.c | 2 +-
2 files changed, 4 insertions(+), 1 deletion(-)
#diff --git a/ChangeLog b/ChangeLog
#index ce330831..8a27a9a6 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,5 +1,8 @@
# 2021-03-13 Niels Möller <nisse@lysator.liu.se>
#
#+ * gostdsa-vko.c (gostdsa_vko): Use ecc_mod_mul_canonical to
#+ compute the scalar used for ecc multiplication.
#+
# * eddsa-hash.c (_eddsa_hash): Ensure result is canonically
# reduced. Two of the three call sites need that.
#
--- a/gostdsa-vko.c
+++ b/gostdsa-vko.c
@@ -87,7 +87,7 @@ gostdsa_vko (const struct ecc_scalar *pr
if (mpn_zero_p (UKM, size))
UKM[0] = 1;
- ecc_mod_mul (&ecc->q, TEMP, priv->p, UKM); /* TEMP = UKM * priv */
+ ecc_mod_mul_canonical (&ecc->q, TEMP, priv->p, UKM, TEMP); /* TEMP = UKM * priv */
ecc->mul (ecc, XYZ, TEMP, pub->p, scratch + 4*size); /* XYZ = UKM * priv * pub */
ecc->h_to_a (ecc, 0, TEMP, XYZ, scratch + 5*size); /* TEMP = XYZ */
mpn_get_base256_le (out, bsize, TEMP, size);

17
nettle.spec
View File

@ -1,12 +1,21 @@
Name: nettle
Version: 3.6
Release: 5
Release: 6
Summary: A low-level cryptographic library
License: LGPLv3+ or GPLv2+
URL: https://www.lysator.liu.se/~nisse/nettle/
Source0: https://www.lysator.liu.se/~nisse/archive/%{name}-%{version}.tar.gz
Patch0: 0000-nettle-3.3-remove-ecc-testsuite.patch
Patch6000: backport-0001-CVE-2021-20305.patch
Patch6001: backport-0002-CVE-2021-20305.patch
Patch6002: backport-0003-CVE-2021-20305.patch
Patch6003: backport-0004-CVE-2021-20305.patch
Patch6004: backport-0005-CVE-2021-20305.patch
Patch6005: backport-0006-CVE-2021-20305.patch
Patch6006: backport-0007-CVE-2021-20305.patch
BuildRequires: automake autoconf fipscheck gcc gettext-devel gmp-devel libtool m4
BuildRequires: nettle
@ -77,6 +86,12 @@ make check
%ldconfig_scriptlets
%changelog
* Mon Apr 19 2021 xihaochen <xihaochen@huawei.com> - 3.6-6
- Type:CVE
- CVE:CVE-2021-20305
- SUG:NA
- DESC:fix CVE-2021-20305
* Tue Jul 21 2020 cuibaobao <cuibaobao1@huawei.com> - 3.6-5
- Type:update
- Id:NA