openssl: fix CVE-2023-464 and CVE-2023-465

Apply two patches fixing low-severity vulnerabilities related to
certificate policies validation:

- Excessive Resource Usage Verifying X.509 Policy Constraints
  (CVE-2023-0464)
  Severity: Low
  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.
  Policy processing is disabled by default but can be enabled by passing
  the `-policy' argument to the command line utilities or by calling the
  `X509_VERIFY_PARAM_set1_policies()' function.

- Invalid certificate policies in leaf certificates are silently ignored
  (CVE-2023-0465)
  Severity: Low
  Applications that use a non-default option when verifying certificates
  may be vulnerable to an attack from a malicious CA to circumvent
  certain checks.
  Invalid certificate policies in leaf certificates are silently ignored
  by OpenSSL and other certificate policy checks are skipped for that
  certificate.  A malicious CA could use this to deliberately assert
  invalid certificate policies in order to circumvent policy checking on
  the certificate altogether.
  Policy processing is disabled by default but can be enabled by passing
  the `-policy' argument to the command line utilities or by calling the
  `X509_VERIFY_PARAM_set1_policies()' function.

Note: OpenSSL also released a fix for low-severity security advisory
CVE-2023-466.  It is not included here because the fix only changes the
documentation, which is not built nor included in any OpenWrt package.

Due to the low-severity of these issues, there will be not be an
immediate new release of OpenSSL.

Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>

1 files changed, 48 insertions, 0 deletions

diff --git a/package/libs/openssl/patches/210-Ensure-that-EXFLAG_INVALID_POLICY-is-checked-even-in.patch b/package/libs/openssl/patches/210-Ensure-that-EXFLAG_INVALID_POLICY-is-checked-even-in.patch
new file mode 100644
index 0000000000..ffb7317d7c
--- /dev/null
+++ b/package/libs/openssl/patches/210-Ensure-that-EXFLAG_INVALID_POLICY-is-checked-even-in.patch
@@ -0,0 +1,48 @@
+From b013765abfa80036dc779dd0e50602c57bb3bf95 Mon Sep 17 00:00:00 2001
+From: Matt Caswell <matt@openssl.org>
+Date: Tue, 7 Mar 2023 16:52:55 +0000
+Subject: [PATCH] Ensure that EXFLAG_INVALID_POLICY is checked even in leaf
+ certs
+
+Even though we check the leaf cert to confirm it is valid, we
+later ignored the invalid flag and did not notice that the leaf
+cert was bad.
+
+Fixes: CVE-2023-0465
+
+Reviewed-by: Hugo Landau <hlandau@openssl.org>
+Reviewed-by: Tomas Mraz <tomas@openssl.org>
+(Merged from https://github.com/openssl/openssl/pull/20588)
+
+diff --git a/crypto/x509/x509_vfy.c b/crypto/x509/x509_vfy.c
+index 925fbb5412..1dfe4f9f31 100644
+--- a/crypto/x509/x509_vfy.c
++++ b/crypto/x509/x509_vfy.c
+@@ -1649,18 +1649,25 @@ static int check_policy(X509_STORE_CTX *ctx)
+     }
+     /* Invalid or inconsistent extensions */
+     if (ret == X509_PCY_TREE_INVALID) {
+-        int i;
++        int i, cbcalled = 0;
+ 
+         /* Locate certificates with bad extensions and notify callback. */
+-        for (i = 1; i < sk_X509_num(ctx->chain); i++) {
++        for (i = 0; i < sk_X509_num(ctx->chain); i++) {
+             X509 *x = sk_X509_value(ctx->chain, i);
+ 
+             if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
+                 continue;
++            cbcalled = 1;
+             if (!verify_cb_cert(ctx, x, i,
+                                 X509_V_ERR_INVALID_POLICY_EXTENSION))
+                 return 0;
+         }
++        if (!cbcalled) {
++            /* Should not be able to get here */
++            X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
++            return 0;
++        }
++        /* The callback ignored the error so we return success */
+         return 1;
+     }
+     if (ret == X509_PCY_TREE_FAILURE) {