From b13733502d829f13ca7af71a9c34ff30f75e54f2 Mon Sep 17 00:00:00 2001 From: guoyayun Date: Mon, 3 Apr 2023 20:24:53 +0800 Subject: [PATCH] Backport-CVE-2023-0464-x509-excessive-resource-use-verifying-policy-constraints --- ...esource-use-verifying-policy-constra.patch | 221 ++++++++++++++++++ crypto/x509/pcy_local.h | 8 +- crypto/x509/pcy_node.c | 12 +- crypto/x509/pcy_tree.c | 36 ++- 4 files changed, 263 insertions(+), 14 deletions(-) create mode 100644 Backport-CVE-2023-0464-x509-excessive-resource-use-verifying-policy-constra.patch diff --git a/Backport-CVE-2023-0464-x509-excessive-resource-use-verifying-policy-constra.patch b/Backport-CVE-2023-0464-x509-excessive-resource-use-verifying-policy-constra.patch new file mode 100644 index 0000000000..0a4937481c --- /dev/null +++ b/Backport-CVE-2023-0464-x509-excessive-resource-use-verifying-policy-constra.patch @@ -0,0 +1,221 @@ +From 959c59c7a0164117e7f8366466a32bb1f8d77ff1 Mon Sep 17 00:00:00 2001 +From: Pauli +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 +Reviewed-by: Shane Lontis +(Merged from https://github.com/openssl/openssl/pull/20568) +--- + 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 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) +-- +2.27.0 + 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 5bee8c2a0b..a0ccbd01d4 100644 --- a/crypto/x509/pcy_node.c +++ b/crypto/x509/pcy_node.c @@ -59,16 +59,21 @@ 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) return NULL; 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; @@ -88,7 +93,7 @@ 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) { @@ -101,6 +106,7 @@ 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 4b954b0776..95fb46f4ec 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) @@ -161,6 +172,9 @@ static int tree_init(X509_POLICY_TREE **ptree, STACK_OF(X509) *certs, if ((tree = OPENSSL_zalloc(sizeof(*tree))) == NULL) 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. * @@ -177,7 +191,7 @@ 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; } @@ -236,7 +250,8 @@ 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; @@ -246,13 +261,13 @@ 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; @@ -265,7 +280,8 @@ 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; @@ -273,7 +289,7 @@ 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; @@ -304,7 +320,7 @@ 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; } @@ -367,7 +383,7 @@ 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; } @@ -550,7 +566,7 @@ 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(); @@ -577,7 +593,7 @@ 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) -- Gitee