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From 28b69c9b4cf451655fe5aa5904294512fa4706c7 Mon Sep 17 00:00:00 2001
From: Matt Caswell <matt@openssl.org>
Date: Tue, 14 Mar 2023 12:59:14 +0000
Subject: [PATCH] Prepare for 3.1.1

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Release: yes
---
 CHANGES.md  | 4 ++++
 NEWS.md     | 4 ++++
 VERSION.dat | 6 +++---
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/CHANGES.md b/CHANGES.md
index 762f42e2c449..950390780ba1 100644
--- CHANGES.md.orig
+++ CHANGES.md
@@ -22,6 +22,10 @@ OpenSSL Releases
 OpenSSL 3.1
 -----------
 
+### Changes between 3.1.0 and 3.1.1 [xx XXX xxxx]
+
+ * none yet
+
 ### Changes between 3.0 and 3.1.0 [14 Mar 2023]
 
  * Add FIPS provider configuration option to enforce the
diff --git a/NEWS.md b/NEWS.md
index 7846919675d5..c243c5e6818a 100644
--- NEWS.md.orig
+++ NEWS.md
@@ -19,6 +19,10 @@ OpenSSL Releases
 OpenSSL 3.1
 -----------
 
+### Major changes between OpenSSL 3.1.0 and OpenSSL 3.1.1 [under development]
+
+  * none
+
 ### Major changes between OpenSSL 3.0 and OpenSSL 3.1.0 [14 Mar 2023]
 
   * SSL 3, TLS 1.0, TLS 1.1, and DTLS 1.0 only work at security level 0.
From b15797a81a76fd62eedf3ffda91dcf5162b51184 Mon Sep 17 00:00:00 2001
From: Pauli <pauli@openssl.org>
Date: Wed, 15 Mar 2023 14:13:22 +1100
Subject: [PATCH] changes: note about policy tree size limits and circumvention

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/20570)
---
 CHANGES.md | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/CHANGES.md b/CHANGES.md
index 950390780ba1..99cabb3057fb 100644
--- CHANGES.md.orig
+++ CHANGES.md
@@ -24,7 +24,14 @@ OpenSSL 3.1
 
 ### Changes between 3.1.0 and 3.1.1 [xx XXX xxxx]
 
- * none yet
+ * Limited the number of nodes created in a policy tree to mitigate
+   against CVE-2023-0464.  The default limit is set to 1000 nodes, which
+   should be sufficient for most installations.  If required, the limit
+   can be adjusted by setting the OPENSSL_POLICY_TREE_NODES_MAX build
+   time define to a desired maximum number of nodes or zero to allow
+   unlimited growth.
+
+   *Paul Dale*
 
 ### Changes between 3.0 and 3.1.0 [14 Mar 2023]
 
From 2017771e2db3e2b96f89bbe8766c3209f6a99545 Mon Sep 17 00:00:00 2001
From: Pauli <pauli@openssl.org>
Date: Wed, 8 Mar 2023 15:28:20 +1100
Subject: [PATCH] x509: excessive resource use verifying policy constraints

A security vulnerability has been identified in all supported versions
of OpenSSL related to the verification of X.509 certificate chains
that include policy constraints.  Attackers may be able to exploit this
vulnerability by creating a malicious certificate chain that triggers
exponential use of computational resources, leading to a denial-of-service
(DoS) attack on affected systems.

Fixes CVE-2023-0464

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/20570)
---
 crypto/x509/pcy_local.h |  8 +++++++-
 crypto/x509/pcy_node.c  | 12 +++++++++---
 crypto/x509/pcy_tree.c  | 36 ++++++++++++++++++++++++++----------
 3 files changed, 42 insertions(+), 14 deletions(-)

diff --git a/crypto/x509/pcy_local.h b/crypto/x509/pcy_local.h
index 18b53cc09ebf..cba107ca0358 100644
--- crypto/x509/pcy_local.h.orig
+++ crypto/x509/pcy_local.h
@@ -111,6 +111,11 @@ struct X509_POLICY_LEVEL_st {
 };
 
 struct X509_POLICY_TREE_st {
+    /* The number of nodes in the tree */
+    size_t node_count;
+    /* The maximum number of nodes in the tree */
+    size_t node_maximum;
+
     /* This is the tree 'level' data */
     X509_POLICY_LEVEL *levels;
     int nlevel;
@@ -157,7 +162,8 @@ X509_POLICY_NODE *ossl_policy_tree_find_sk(STACK_OF(X509_POLICY_NODE) *sk,
 X509_POLICY_NODE *ossl_policy_level_add_node(X509_POLICY_LEVEL *level,
                                              X509_POLICY_DATA *data,
                                              X509_POLICY_NODE *parent,
-                                             X509_POLICY_TREE *tree);
+                                             X509_POLICY_TREE *tree,
+                                             int extra_data);
 void ossl_policy_node_free(X509_POLICY_NODE *node);
 int ossl_policy_node_match(const X509_POLICY_LEVEL *lvl,
                            const X509_POLICY_NODE *node, const ASN1_OBJECT *oid);
diff --git a/crypto/x509/pcy_node.c b/crypto/x509/pcy_node.c
index 9d9a7ea1799c..450f95a655fb 100644
--- crypto/x509/pcy_node.c.orig
+++ crypto/x509/pcy_node.c
@@ -59,10 +59,15 @@ X509_POLICY_NODE *ossl_policy_level_find_node(const X509_POLICY_LEVEL *level,
 X509_POLICY_NODE *ossl_policy_level_add_node(X509_POLICY_LEVEL *level,
                                              X509_POLICY_DATA *data,
                                              X509_POLICY_NODE *parent,
-                                             X509_POLICY_TREE *tree)
+                                             X509_POLICY_TREE *tree,
+                                             int extra_data)
 {
     X509_POLICY_NODE *node;
 
+    /* Verify that the tree isn't too large.  This mitigates CVE-2023-0464 */
+    if (tree->node_maximum > 0 && tree->node_count >= tree->node_maximum)
+        return NULL;
+
     node = OPENSSL_zalloc(sizeof(*node));
     if (node == NULL) {
         ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE);
@@ -70,7 +75,7 @@ X509_POLICY_NODE *ossl_policy_level_add_node(X509_POLICY_LEVEL *level,
     }
     node->data = data;
     node->parent = parent;
-    if (level) {
+    if (level != NULL) {
         if (OBJ_obj2nid(data->valid_policy) == NID_any_policy) {
             if (level->anyPolicy)
                 goto node_error;
@@ -90,7 +95,7 @@ X509_POLICY_NODE *ossl_policy_level_add_node(X509_POLICY_LEVEL *level,
         }
     }
 
-    if (tree) {
+    if (extra_data) {
         if (tree->extra_data == NULL)
             tree->extra_data = sk_X509_POLICY_DATA_new_null();
         if (tree->extra_data == NULL){
@@ -103,6 +108,7 @@ X509_POLICY_NODE *ossl_policy_level_add_node(X509_POLICY_LEVEL *level,
         }
     }
 
+    tree->node_count++;
     if (parent)
         parent->nchild++;
 
diff --git a/crypto/x509/pcy_tree.c b/crypto/x509/pcy_tree.c
index fa45da5117a1..f953a05a41a6 100644
--- crypto/x509/pcy_tree.c.orig
+++ crypto/x509/pcy_tree.c
@@ -14,6 +14,17 @@
 
 #include "pcy_local.h"
 
+/*
+ * If the maximum number of nodes in the policy tree isn't defined, set it to
+ * a generous default of 1000 nodes.
+ *
+ * Defining this to be zero means unlimited policy tree growth which opens the
+ * door on CVE-2023-0464.
+ */
+#ifndef OPENSSL_POLICY_TREE_NODES_MAX
+# define OPENSSL_POLICY_TREE_NODES_MAX 1000
+#endif
+
 static void expected_print(BIO *channel,
                            X509_POLICY_LEVEL *lev, X509_POLICY_NODE *node,
                            int indent)
@@ -163,6 +174,9 @@ static int tree_init(X509_POLICY_TREE **ptree, STACK_OF(X509) *certs,
         return X509_PCY_TREE_INTERNAL;
     }
 
+    /* Limit the growth of the tree to mitigate CVE-2023-0464 */
+    tree->node_maximum = OPENSSL_POLICY_TREE_NODES_MAX;
+
     /*
      * http://tools.ietf.org/html/rfc5280#section-6.1.2, figure 3.
      *
@@ -180,7 +194,7 @@ static int tree_init(X509_POLICY_TREE **ptree, STACK_OF(X509) *certs,
     if ((data = ossl_policy_data_new(NULL,
                                      OBJ_nid2obj(NID_any_policy), 0)) == NULL)
         goto bad_tree;
-    if (ossl_policy_level_add_node(level, data, NULL, tree) == NULL) {
+    if (ossl_policy_level_add_node(level, data, NULL, tree, 1) == NULL) {
         ossl_policy_data_free(data);
         goto bad_tree;
     }
@@ -239,7 +253,8 @@ static int tree_init(X509_POLICY_TREE **ptree, STACK_OF(X509) *certs,
  * Return value: 1 on success, 0 otherwise
  */
 static int tree_link_matching_nodes(X509_POLICY_LEVEL *curr,
-                                    X509_POLICY_DATA *data)
+                                    X509_POLICY_DATA *data,
+                                    X509_POLICY_TREE *tree)
 {
     X509_POLICY_LEVEL *last = curr - 1;
     int i, matched = 0;
@@ -249,13 +264,13 @@ static int tree_link_matching_nodes(X509_POLICY_LEVEL *curr,
         X509_POLICY_NODE *node = sk_X509_POLICY_NODE_value(last->nodes, i);
 
         if (ossl_policy_node_match(last, node, data->valid_policy)) {
-            if (ossl_policy_level_add_node(curr, data, node, NULL) == NULL)
+            if (ossl_policy_level_add_node(curr, data, node, tree, 0) == NULL)
                 return 0;
             matched = 1;
         }
     }
     if (!matched && last->anyPolicy) {
-        if (ossl_policy_level_add_node(curr, data, last->anyPolicy, NULL) == NULL)
+        if (ossl_policy_level_add_node(curr, data, last->anyPolicy, tree, 0) == NULL)
             return 0;
     }
     return 1;
@@ -268,7 +283,8 @@ static int tree_link_matching_nodes(X509_POLICY_LEVEL *curr,
  * Return value: 1 on success, 0 otherwise.
  */
 static int tree_link_nodes(X509_POLICY_LEVEL *curr,
-                           const X509_POLICY_CACHE *cache)
+                           const X509_POLICY_CACHE *cache,
+                           X509_POLICY_TREE *tree)
 {
     int i;
 
@@ -276,7 +292,7 @@ static int tree_link_nodes(X509_POLICY_LEVEL *curr,
         X509_POLICY_DATA *data = sk_X509_POLICY_DATA_value(cache->data, i);
 
         /* Look for matching nodes in previous level */
-        if (!tree_link_matching_nodes(curr, data))
+        if (!tree_link_matching_nodes(curr, data, tree))
             return 0;
     }
     return 1;
@@ -307,7 +323,7 @@ static int tree_add_unmatched(X509_POLICY_LEVEL *curr,
     /* Curr may not have anyPolicy */
     data->qualifier_set = cache->anyPolicy->qualifier_set;
     data->flags |= POLICY_DATA_FLAG_SHARED_QUALIFIERS;
-    if (ossl_policy_level_add_node(curr, data, node, tree) == NULL) {
+    if (ossl_policy_level_add_node(curr, data, node, tree, 1) == NULL) {
         ossl_policy_data_free(data);
         return 0;
     }
@@ -370,7 +386,7 @@ static int tree_link_any(X509_POLICY_LEVEL *curr,
     /* Finally add link to anyPolicy */
     if (last->anyPolicy &&
             ossl_policy_level_add_node(curr, cache->anyPolicy,
-                                       last->anyPolicy, NULL) == NULL)
+                                       last->anyPolicy, tree, 0) == NULL)
         return 0;
     return 1;
 }
@@ -553,7 +569,7 @@ static int tree_calculate_user_set(X509_POLICY_TREE *tree,
             extra->flags = POLICY_DATA_FLAG_SHARED_QUALIFIERS
                 | POLICY_DATA_FLAG_EXTRA_NODE;
             node = ossl_policy_level_add_node(NULL, extra, anyPolicy->parent,
-                                              tree);
+                                              tree, 1);
         }
         if (!tree->user_policies) {
             tree->user_policies = sk_X509_POLICY_NODE_new_null();
@@ -580,7 +596,7 @@ static int tree_evaluate(X509_POLICY_TREE *tree)
 
     for (i = 1; i < tree->nlevel; i++, curr++) {
         cache = ossl_policy_cache_set(curr->cert);
-        if (!tree_link_nodes(curr, cache))
+        if (!tree_link_nodes(curr, cache, tree))
             return X509_PCY_TREE_INTERNAL;
 
         if (!(curr->flags & X509_V_FLAG_INHIBIT_ANY)