From 6e0d3b16e6d86b43b7921a01ab67842eedebd3ff Mon Sep 17 00:00:00 2001
From: Dmitry Belyavskiy <dbelyavs@redhat.com>
Date: Wed, 18 Oct 2023 11:20:31 +0200
Subject: [PATCH] Excessive time spent checking DH q parameter value

Resolves: RHEL-5308
---
 0127-CVE-2023-3817.patch | 57 ++++++++++++++++++++++++++++++++++++++++
 openssl.spec             |  3 +++
 2 files changed, 60 insertions(+)
 create mode 100644 0127-CVE-2023-3817.patch

diff --git a/0127-CVE-2023-3817.patch b/0127-CVE-2023-3817.patch
new file mode 100644
index 0000000..5fc72e7
--- /dev/null
+++ b/0127-CVE-2023-3817.patch
@@ -0,0 +1,57 @@
+diff --git a/crypto/dh/dh_check.c b/crypto/dh/dh_check.c
+index aef6f9b1b7..fbe2797569 100644
+--- a/crypto/dh/dh_check.c
++++ b/crypto/dh/dh_check.c
+@@ -143,7 +143,7 @@ int DH_check(const DH *dh, int *ret)
+ #ifdef FIPS_MODULE
+     return DH_check_params(dh, ret);
+ #else
+-    int ok = 0, r;
++    int ok = 0, r, q_good = 0;
+     BN_CTX *ctx = NULL;
+     BIGNUM *t1 = NULL, *t2 = NULL;
+     int nid = DH_get_nid((DH *)dh);
+@@ -172,6 +172,13 @@ int DH_check(const DH *dh, int *ret)
+         goto err;
+ 
+     if (dh->params.q != NULL) {
++        if (BN_ucmp(dh->params.p, dh->params.q) > 0)
++            q_good = 1;
++        else
++            *ret |= DH_CHECK_INVALID_Q_VALUE;
++    }
++
++    if (q_good) {
+         if (BN_cmp(dh->params.g, BN_value_one()) <= 0)
+             *ret |= DH_NOT_SUITABLE_GENERATOR;
+         else if (BN_cmp(dh->params.g, dh->params.p) >= 0)
+diff --git a/test/dhtest.c b/test/dhtest.c
+index f8dd8f3aa7..d02b3b7c58 100644
+--- a/test/dhtest.c
++++ b/test/dhtest.c
+@@ -124,6 +124,15 @@ static int dh_test(void)
+     /* We'll have a stale error on the queue from the above test so clear it */
+     ERR_clear_error();
+ 
++    if (!TEST_ptr(BN_copy(q, p)) || !TEST_true(BN_add(q, q, BN_value_one())))
++        goto err3;
++
++    if (!TEST_true(DH_check(dh, &i)))
++        goto err3;
++    if (!TEST_true(i & DH_CHECK_INVALID_Q_VALUE)
++        || !TEST_false(i & DH_CHECK_Q_NOT_PRIME))
++        goto err3;
++
+     /* Modulus of size: dh check max modulus bits + 1 */
+     if (!TEST_true(BN_set_word(p, 1))
+             || !TEST_true(BN_lshift(p, p, OPENSSL_DH_CHECK_MAX_MODULUS_BITS)))
+@@ -135,6 +144,9 @@ static int dh_test(void)
+     if (!TEST_false(DH_check(dh, &i)))
+         goto err3;
+ 
++    /* We'll have a stale error on the queue from the above test so clear it */
++    ERR_clear_error();
++
+     /*
+      * II) key generation
+      */
diff --git a/openssl.spec b/openssl.spec
index ab0c637..a59230a 100644
--- a/openssl.spec
+++ b/openssl.spec
@@ -199,6 +199,7 @@ Patch122: 0122-CVE-2023-2650.patch
 Patch123: 0123-ibmca-atexit-crash.patch
 Patch125: 0125-CVE-2023-2975.patch
 Patch126: 0126-CVE-2023-3446.patch
+Patch127: 0127-CVE-2023-3817.patch
 
 License: ASL 2.0
 URL: http://www.openssl.org/
@@ -540,6 +541,8 @@ ln -s /etc/crypto-policies/back-ends/openssl_fips.config $RPM_BUILD_ROOT%{_sysco
   Resolves: RHEL-5302
 - Excessive time spent checking DH keys and parameters (CVE-2023-3446)
   Resolves: RHEL-5306
+- Excessive time spent checking DH q parameter value (CVE-2023-3817)
+  Resolves: RHEL-5308
 
 * Wed Jul 12 2023 Dmitry Belyavskiy <dbelyavs@redhat.com> - 1:3.0.7-24
 - Make FIPS module configuration more crypto-policies friendly