File openssl-1_1-CVE-2023-3817.patch of Package openssl-1_1

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File openssl-1_1-CVE-2023-3817.patch of Package openssl-1_1

From 91ddeba0f2269b017dc06c46c993a788974b1aa5 Mon Sep 17 00:00:00 2001
From: Tomas Mraz <tomas@openssl.org>
Date: Fri, 21 Jul 2023 11:39:41 +0200
Subject: [PATCH 198/200] DH_check(): Do not try checking q properties if it is
 obviously invalid

If  |q| >= |p| then the q value is obviously wrong as q
is supposed to be a prime divisor of p-1.

We check if p is overly large so this added test implies that
q is not large either when performing subsequent tests using that
q value.

Otherwise if it is too large these additional checks of the q value
such as the primality test can then trigger DoS by doing overly long
computations.

Fixes CVE-2023-3817

Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/21551)

Index: openssl-1.1.1l/crypto/dh/dh_check.c
===================================================================
--- openssl-1.1.1l.orig/crypto/dh/dh_check.c
+++ openssl-1.1.1l/crypto/dh/dh_check.c
@@ -105,7 +105,7 @@ int DH_check_ex(const DH *dh)
 /* Note: according to documentation - this only checks the params */
 int DH_check(const DH *dh, int *ret)
 {
-    int ok = 0, r;
+    int ok = 0, r, q_good = 0;
     BN_CTX *ctx = NULL;
     BIGNUM *t1 = NULL, *t2 = NULL;
 
@@ -130,7 +130,14 @@ int DH_check(const DH *dh, int *ret)
     if (t2 == NULL)
         goto err;
 
-    if (dh->q) {
+    if (dh->q != NULL) {
+        if (BN_ucmp(dh->p, dh->q) > 0)
+            q_good = 1;
+        else
+            *ret |= DH_CHECK_INVALID_Q_VALUE;
+    }
+
+    if (q_good) {
         if (BN_cmp(dh->g, BN_value_one()) <= 0)
             *ret |= DH_NOT_SUITABLE_GENERATOR;
         else if (BN_cmp(dh->g, dh->p) >= 0)
From 34d0f5cb93680a5286d1eb59125631ec8fd6dc81 Mon Sep 17 00:00:00 2001
From: Tomas Mraz <tomas@openssl.org>
Date: Tue, 25 Jul 2023 15:56:53 +0200
Subject: [PATCH] dhtest.c: Add test of DH_check() with q = p + 1

This must fail with DH_CHECK_INVALID_Q_VALUE and
with DH_CHECK_Q_NOT_PRIME unset.

Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/21551)
---
 test/dhtest.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/dhtest.c b/test/dhtest.c
index 00b3c471015d..d7e10ebda9b5 100644
--- a/test/dhtest.c
+++ b/test/dhtest.c
@@ -123,6 +123,15 @@ static int dh_test(void)
     /* check whether the public key was calculated correctly */
     TEST_uint_eq(BN_get_word(pub_key2), 3331L);
 
+    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)))
@@ -134,6 +143,9 @@ 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
      */

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File openssl-1_1-CVE-2023-3817.patch of Package openssl-1_1

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