Refactor X.509 path validation

Splits path building, path validation, CRL checks, and OCSP checks
into distinct functions in namespace PKIX. The previous path validation
APIs remain.

Fixes to OCSP to store more information and to handle modern OCSP setups
in at least some situations.

1 files changed, 93 insertions, 15 deletions

diff --git a/src/lib/x509/x509path.h b/src/lib/x509/x509path.h
index f65652e59..414a877da 100644
--- a/src/lib/x509/x509path.h
+++ b/src/lib/x509/x509path.h
@@ -11,6 +11,8 @@
 #include <botan/cert_status.h>
 #include <botan/x509cert.h>
 #include <botan/certstor.h>
+#include <botan/ocsp.h>
+#include <functional>
 #include <set>
 #include <chrono>
 
@@ -28,7 +30,8 @@ class BOTAN_DLL Path_Validation_Restrictions
       *        operations, eg 80 means 2^80) of a signature. Signatures
       *        weaker than this are rejected. If more than 80, SHA-1
       *        signatures are also rejected.
-      * @param ocsp_all_intermediates
+      * @param ocsp_all_intermediates Make OCSP requests for all CAs as
+      * well as end entity (if OCSP enabled in path validation request)
       */
       Path_Validation_Restrictions(bool require_rev = false,
                                    size_t minimum_key_strength = 80,
@@ -39,7 +42,8 @@ class BOTAN_DLL Path_Validation_Restrictions
       * @param minimum_key_strength is the minimum strength (in terms of
       *        operations, eg 80 means 2^80) of a signature. Signatures
       *        weaker than this are rejected.
-      * @param ocsp_all_intermediates
+      * @param ocsp_all_intermediates Make OCSP requests for all CAs as
+      * well as end entity (if OCSP enabled in path validation request)
       * @param trusted_hashes a set of trusted hashes. Any signatures
       *        created using a hash other than one of these will be
       *        rejected.
@@ -106,6 +110,7 @@ class BOTAN_DLL Path_Validation_Result
 
       /**
       * @return the full path from subject to trust root
+      * This path may be empty
       */
       const std::vector<std::shared_ptr<const X509_Certificate>>& cert_path() const { return m_cert_path; }
 
@@ -151,52 +156,121 @@ class BOTAN_DLL Path_Validation_Result
       explicit Path_Validation_Result(Certificate_Status_Code status) : m_overall(status) {}
 
    private:
-      friend Path_Validation_Result BOTAN_DLL x509_path_validate(
-         const std::vector<X509_Certificate>& end_certs,
-         const Path_Validation_Restrictions& restrictions,
-         const std::vector<Certificate_Store*>& certstores);
-
       Certificate_Status_Code m_overall;
       std::vector<std::set<Certificate_Status_Code>> m_all_status;
       std::vector<std::shared_ptr<const X509_Certificate>> m_cert_path;
    };
 
+namespace PKIX {
+
+/**
+* Build certificate path
+* @param cert_path_out output parameter, cert_path will be appended to this vector
+* @param trusted_certstores list of certificate stores that contain trusted certificates
+* @param end_entity the cert to be validated
+* @param end_entity_extra optional list of additional untrusted certs for path building
+* @return result of the path building operation (OK or error)
+*/
+Certificate_Status_Code
+BOTAN_DLL build_certificate_path(std::vector<std::shared_ptr<const X509_Certificate>>& cert_path_out,
+                                 const std::vector<Certificate_Store*>& trusted_certstores,
+                                 const std::shared_ptr<const X509_Certificate>& end_entity,
+                                 const std::vector<std::shared_ptr<const X509_Certificate>>& end_entity_extra);
+
+/**
+* Perform certificate validation
+* @param cert_path path built by build_certificate_path with OK result
+* @param ref_time whatever time you want to perform the validation
+* against (normally current system clock)
+* @param hostname the hostname
+* @param usage end entity usage checks
+* @param min_signature_algo_strength 80 or 128 typically
+* @param trusted_hashes set of trusted hash functions,
+* empty means accept any hash we have an OID for
+*/
+std::vector<std::set<Certificate_Status_Code>>
+BOTAN_DLL check_chain(const std::vector<std::shared_ptr<const X509_Certificate>>& cert_path,
+                      std::chrono::system_clock::time_point ref_time,
+                      const std::string& hostname,
+                      Usage_Type usage,
+                      size_t min_signature_algo_strength,
+                      const std::set<std::string>& trusted_hashes);
+
+std::vector<std::set<Certificate_Status_Code>>
+BOTAN_DLL check_ocsp(const std::vector<std::shared_ptr<const X509_Certificate>>& cert_path,
+                     const std::vector<std::shared_ptr<const OCSP::Response>>& ocsp_responses,
+                     const std::vector<Certificate_Store*>& certstores,
+                     std::chrono::system_clock::time_point ref_time);
+
+std::vector<std::set<Certificate_Status_Code>>
+BOTAN_DLL check_crl(const std::vector<std::shared_ptr<const X509_Certificate>>& cert_path,
+                    const std::vector<std::shared_ptr<const X509_CRL>>& crls,
+                    std::chrono::system_clock::time_point ref_time);
+
+std::vector<std::set<Certificate_Status_Code>>
+BOTAN_DLL check_crl(const std::vector<std::shared_ptr<const X509_Certificate>>& cert_path,
+                    const std::vector<Certificate_Store*>& certstores,
+                    std::chrono::system_clock::time_point ref_time);
+
+#if defined(BOTAN_TARGET_OS_HAS_THREADS) && defined(BOTAN_HAS_HTTP_UTIL)
+
+std::vector<std::set<Certificate_Status_Code>>
+BOTAN_DLL check_ocsp_online(const std::vector<std::shared_ptr<const X509_Certificate>>& cert_path,
+                            const std::vector<Certificate_Store*>& trusted_certstores,
+                            std::chrono::system_clock::time_point ref_time,
+                            std::chrono::milliseconds timeout,
+                            bool ocsp_check_intermediate_CAs);
+
+std::vector<std::set<Certificate_Status_Code>>
+BOTAN_DLL check_crl_online(const std::vector<std::shared_ptr<const X509_Certificate>>& cert_path,
+                           const std::vector<Certificate_Store*>& trusted_certstores,
+                           std::chrono::system_clock::time_point ref_time,
+                           std::chrono::milliseconds timeout);
+
+#endif
+
+}
+
 
 /**
 * PKIX Path Validation
 * @param end_certs certificate chain to validate
 * @param restrictions path validation restrictions
-* @param certstores list of certificate stores that contain trusted certificates
+* @param trusted_roots list of certificate stores that contain trusted certificates
 * @param hostname if not empty, compared against the DNS name in end_certs[0]
 * @param usage if not set to UNSPECIFIED, compared against the key usage in end_certs[0]
 * @param validation_time what reference time to use for validation
+* @param ocsp_timeout timeoutput for OCSP operations, 0 disables OCSP check
 * @return result of the path validation
 */
 Path_Validation_Result BOTAN_DLL x509_path_validate(
    const std::vector<X509_Certificate>& end_certs,
    const Path_Validation_Restrictions& restrictions,
-   const std::vector<Certificate_Store*>& certstores,
+   const std::vector<Certificate_Store*>& trusted_roots,
    const std::string& hostname = "",
    Usage_Type usage = Usage_Type::UNSPECIFIED,
-   std::chrono::system_clock::time_point validation_time = std::chrono::system_clock::now());
+   std::chrono::system_clock::time_point validation_time = std::chrono::system_clock::now(),
+   std::chrono::milliseconds ocsp_timeout = std::chrono::milliseconds(0));
 
 /**
 * PKIX Path Validation
 * @param end_cert certificate to validate
 * @param restrictions path validation restrictions
-* @param certstores list of stores that contain trusted certificates
+* @param trusted_roots list of stores that contain trusted certificates
 * @param hostname if not empty, compared against the DNS name in end_cert
 * @param usage if not set to UNSPECIFIED, compared against the key usage in end_cert
 * @param validation_time what reference time to use for validation
+* @param ocsp_timeout timeoutput for OCSP operations, 0 disables OCSP check
 * @return result of the path validation
 */
 Path_Validation_Result BOTAN_DLL x509_path_validate(
    const X509_Certificate& end_cert,
    const Path_Validation_Restrictions& restrictions,
-   const std::vector<Certificate_Store*>& certstores,
+   const std::vector<Certificate_Store*>& trusted_roots,
    const std::string& hostname = "",
    Usage_Type usage = Usage_Type::UNSPECIFIED,
-   std::chrono::system_clock::time_point validation_time = std::chrono::system_clock::now());
+   std::chrono::system_clock::time_point validation_time = std::chrono::system_clock::now(),
+   std::chrono::milliseconds ocsp_timeout = std::chrono::milliseconds(0));
 
 /**
 * PKIX Path Validation
@@ -206,6 +280,7 @@ Path_Validation_Result BOTAN_DLL x509_path_validate(
 * @param hostname if not empty, compared against the DNS name in end_cert
 * @param usage if not set to UNSPECIFIED, compared against the key usage in end_cert
 * @param validation_time what reference time to use for validation
+* @param ocsp_timeout timeoutput for OCSP operations, 0 disables OCSP check
 * @return result of the path validation
 */
 Path_Validation_Result BOTAN_DLL x509_path_validate(
@@ -214,7 +289,8 @@ Path_Validation_Result BOTAN_DLL x509_path_validate(
    const Certificate_Store& store,
    const std::string& hostname = "",
    Usage_Type usage = Usage_Type::UNSPECIFIED,
-   std::chrono::system_clock::time_point validation_time = std::chrono::system_clock::now());
+   std::chrono::system_clock::time_point validation_time = std::chrono::system_clock::now(),
+   std::chrono::milliseconds ocsp_timeout = std::chrono::milliseconds(0));
 
 /**
 * PKIX Path Validation
@@ -224,6 +300,7 @@ Path_Validation_Result BOTAN_DLL x509_path_validate(
 * @param hostname if not empty, compared against the DNS name in end_certs[0]
 * @param usage if not set to UNSPECIFIED, compared against the key usage in end_certs[0]
 * @param validation_time what reference time to use for validation
+* @param ocsp_timeout timeoutput for OCSP operations, 0 disables OCSP check
 * @return result of the path validation
 */
 Path_Validation_Result BOTAN_DLL x509_path_validate(
@@ -232,7 +309,8 @@ Path_Validation_Result BOTAN_DLL x509_path_validate(
    const Certificate_Store& store,
    const std::string& hostname = "",
    Usage_Type usage = Usage_Type::UNSPECIFIED,
-   std::chrono::system_clock::time_point validation_time = std::chrono::system_clock::now());
+   std::chrono::system_clock::time_point validation_time = std::chrono::system_clock::now(),
+   std::chrono::milliseconds ocsp_timeout = std::chrono::milliseconds(0));
 
 }