--- /dev/null
+Fix CVE-2018-0495:
+
+https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-0495
+https://www.nccgroup.trust/us/our-research/technical-advisory-return-of-the-hidden-number-problem/
+
+Patch copied from upstream source repository:
+
+https://github.com/openssl/openssl/commit/0c27d793745c7837b13646302b6890a556b7017a
+
+From 0c27d793745c7837b13646302b6890a556b7017a Mon Sep 17 00:00:00 2001
+From: Matt Caswell <matt@openssl.org>
+Date: Fri, 25 May 2018 12:10:13 +0100
+Subject: [PATCH] Add blinding to an ECDSA signature
+
+Keegan Ryan (NCC Group) has demonstrated a side channel attack on an
+ECDSA signature operation. During signing the signer calculates:
+
+s:= k^-1 * (m + r * priv_key) mod order
+
+The addition operation above provides a sufficient signal for a
+flush+reload attack to derive the private key given sufficient signature
+operations.
+
+As a mitigation (based on a suggestion from Keegan) we add blinding to
+the operation so that:
+
+s := k^-1 * blind^-1 (blind * m + blind * r * priv_key) mod order
+
+Since this attack is a localhost side channel only no CVE is assigned.
+
+Reviewed-by: Rich Salz <rsalz@openssl.org>
+---
+ CHANGES | 4 +++
+ crypto/ec/ecdsa_ossl.c | 70 +++++++++++++++++++++++++++++++++++++-----
+ 2 files changed, 67 insertions(+), 7 deletions(-)
+
+diff --git a/crypto/ec/ecdsa_ossl.c b/crypto/ec/ecdsa_ossl.c
+index 72e2f0f28b..449be0e92a 100644
+--- a/crypto/ec/ecdsa_ossl.c
++++ b/crypto/ec/ecdsa_ossl.c
+@@ -210,7 +210,8 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
+ EC_KEY *eckey)
+ {
+ int ok = 0, i;
+- BIGNUM *kinv = NULL, *s, *m = NULL, *tmp = NULL;
++ BIGNUM *kinv = NULL, *s, *m = NULL, *tmp = NULL, *blind = NULL;
++ BIGNUM *blindm = NULL;
+ const BIGNUM *order, *ckinv;
+ BN_CTX *ctx = NULL;
+ const EC_GROUP *group;
+@@ -243,8 +244,18 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
+ }
+ s = ret->s;
+
+- if ((ctx = BN_CTX_new()) == NULL ||
+- (tmp = BN_new()) == NULL || (m = BN_new()) == NULL) {
++ ctx = BN_CTX_secure_new();
++ if (ctx == NULL) {
++ ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_MALLOC_FAILURE);
++ goto err;
++ }
++
++ BN_CTX_start(ctx);
++ tmp = BN_CTX_get(ctx);
++ m = BN_CTX_get(ctx);
++ blind = BN_CTX_get(ctx);
++ blindm = BN_CTX_get(ctx);
++ if (blindm == NULL) {
+ ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+@@ -284,18 +295,64 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
+ }
+ }
+
+- if (!BN_mod_mul(tmp, priv_key, ret->r, order, ctx)) {
++ /*
++ * The normal signature calculation is:
++ *
++ * s := k^-1 * (m + r * priv_key) mod order
++ *
++ * We will blind this to protect against side channel attacks
++ *
++ * s := k^-1 * blind^-1 * (blind * m + blind * r * priv_key) mod order
++ */
++
++ /* Generate a blinding value */
++ do {
++ if (!BN_rand(blind, BN_num_bits(order) - 1, BN_RAND_TOP_ANY,
++ BN_RAND_BOTTOM_ANY))
++ goto err;
++ } while (BN_is_zero(blind));
++ BN_set_flags(blind, BN_FLG_CONSTTIME);
++ BN_set_flags(blindm, BN_FLG_CONSTTIME);
++ BN_set_flags(tmp, BN_FLG_CONSTTIME);
++
++ /* tmp := blind * priv_key * r mod order */
++ if (!BN_mod_mul(tmp, blind, priv_key, order, ctx)) {
+ ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
+ goto err;
+ }
+- if (!BN_mod_add_quick(s, tmp, m, order)) {
++ if (!BN_mod_mul(tmp, tmp, ret->r, order, ctx)) {
+ ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
+ goto err;
+ }
++
++ /* blindm := blind * m mod order */
++ if (!BN_mod_mul(blindm, blind, m, order, ctx)) {
++ ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
++ goto err;
++ }
++
++ /* s : = (blind * priv_key * r) + (blind * m) mod order */
++ if (!BN_mod_add_quick(s, tmp, blindm, order)) {
++ ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
++ goto err;
++ }
++
++ /* s:= s * blind^-1 mod order */
++ if (BN_mod_inverse(blind, blind, order, ctx) == NULL) {
++ ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
++ goto err;
++ }
++ if (!BN_mod_mul(s, s, blind, order, ctx)) {
++ ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
++ goto err;
++ }
++
++ /* s := s * k^-1 mod order */
+ if (!BN_mod_mul(s, s, ckinv, order, ctx)) {
+ ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB);
+ goto err;
+ }
++
+ if (BN_is_zero(s)) {
+ /*
+ * if kinv and r have been supplied by the caller don't to
+@@ -317,9 +374,8 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
+ ECDSA_SIG_free(ret);
+ ret = NULL;
+ }
++ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+- BN_clear_free(m);
+- BN_clear_free(tmp);
+ BN_clear_free(kinv);
+ return ret;
+ }
+--
+2.17.1
+
--- /dev/null
+Fix CVE-2018-0732:
+
+https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-0732
+
+Patch copied from upstream source repository:
+
+https://github.com/openssl/openssl/commit/ea7abeeabf92b7aca160bdd0208636d4da69f4f4
+
+From ea7abeeabf92b7aca160bdd0208636d4da69f4f4 Mon Sep 17 00:00:00 2001
+From: Guido Vranken <guidovranken@gmail.com>
+Date: Mon, 11 Jun 2018 19:38:54 +0200
+Subject: [PATCH] Reject excessively large primes in DH key generation.
+
+CVE-2018-0732
+
+Signed-off-by: Guido Vranken <guidovranken@gmail.com>
+
+(cherry picked from commit 91f7361f47b082ae61ffe1a7b17bb2adf213c7fe)
+
+Reviewed-by: Tim Hudson <tjh@openssl.org>
+Reviewed-by: Matt Caswell <matt@openssl.org>
+(Merged from https://github.com/openssl/openssl/pull/6457)
+---
+ crypto/dh/dh_key.c | 7 ++++++-
+ 1 file changed, 6 insertions(+), 1 deletion(-)
+
+diff --git a/crypto/dh/dh_key.c b/crypto/dh/dh_key.c
+index fce9ff47f3..58003d7087 100644
+--- a/crypto/dh/dh_key.c
++++ b/crypto/dh/dh_key.c
+@@ -78,10 +78,15 @@ static int generate_key(DH *dh)
+ int ok = 0;
+ int generate_new_key = 0;
+ unsigned l;
+- BN_CTX *ctx;
++ BN_CTX *ctx = NULL;
+ BN_MONT_CTX *mont = NULL;
+ BIGNUM *pub_key = NULL, *priv_key = NULL;
+
++ if (BN_num_bits(dh->p) > OPENSSL_DH_MAX_MODULUS_BITS) {
++ DHerr(DH_F_GENERATE_KEY, DH_R_MODULUS_TOO_LARGE);
++ return 0;
++ }
++
+ ctx = BN_CTX_new();
+ if (ctx == NULL)
+ goto err;
+--
+2.17.1
+
HCoop / jackhill / guix / guix.git / commitdiff