Fix excessive resource usage in verifying X509 policy constraints

Resolves: rhbz#2186661
epel8
Dmitry Belyavskiy 2 years ago
parent 35f22d134e
commit 90306b7fd8

@ -0,0 +1,195 @@
diff --git a/crypto/x509/pcy_local.h b/crypto/x509/pcy_local.h
index 18b53cc09e..cba107ca03 100644
--- a/crypto/x509/pcy_local.h
+++ b/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 9d9a7ea179..450f95a655 100644
--- a/crypto/x509/pcy_node.c
+++ b/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 fa45da5117..f953a05a41 100644
--- a/crypto/x509/pcy_tree.c
+++ b/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)

@ -180,6 +180,9 @@ Patch113: 0113-asymciphers-kem-Add-explicit-FIPS-indicator.patch
# https://bugzilla.redhat.com/show_bug.cgi?id=2157951
Patch114: 0114-FIPS-enforce-EMS-support.patch
# X.509 policies minor CVEs
Patch115: 0115-CVE-2023-0464.patch
License: ASL 2.0
URL: http://www.openssl.org/
BuildRequires: gcc g++
@ -512,6 +515,8 @@ install -m644 %{SOURCE9} \
* Tue Apr 18 2023 Dmitry Belyavskiy <dbelyavs@redhat.com> - 1:3.0.7-13
- Enforce using EMS in FIPS mode
Resolves: rhbz#2157951
- Fix excessive resource usage in verifying X509 policy constraints
Resolves: rhbz#2186661
* Fri Mar 24 2023 Clemens Lang <cllang@redhat.com> - 1:3.0.7-12
- Change explicit FIPS indicator for RSA decryption to unapproved

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