1 files changed, 266 insertions, 0 deletions
diff --git a/src/lib/x509/x509_ca.cpp b/src/lib/x509/x509_ca.cpp
new file mode 100644
index 000000000..179d903c4
--- /dev/null
+++ b/src/lib/x509/x509_ca.cpp
@@ -0,0 +1,266 @@
+/*
+* X.509 Certificate Authority
+* (C) 1999-2010 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/x509_ca.h>
+#include <botan/pubkey.h>
+#include <botan/der_enc.h>
+#include <botan/ber_dec.h>
+#include <botan/bigint.h>
+#include <botan/parsing.h>
+#include <botan/oids.h>
+#include <botan/hash.h>
+#include <botan/key_constraint.h>
+#include <algorithm>
+#include <typeinfo>
+#include <iterator>
+#include <set>
+
+namespace Botan {
+
+/*
+* Load the certificate and private key
+*/
+X509_CA::X509_CA(const X509_Certificate& c,
+                 const Private_Key& key,
+                 const std::string& hash_fn,
+                 RandomNumberGenerator& rng) : m_cert(c)
+   {
+   if(!m_cert.is_CA_cert())
+      throw Invalid_Argument("X509_CA: This certificate is not for a CA");
+
+   m_signer = choose_sig_format(key, rng, hash_fn, m_ca_sig_algo);
+   }
+
+/*
+* X509_CA Destructor
+*/
+X509_CA::~X509_CA()
+   {
+   delete m_signer;
+   }
+
+/*
+* Sign a PKCS #10 certificate request
+*/
+X509_Certificate X509_CA::sign_request(const PKCS10_Request& req,
+                                       RandomNumberGenerator& rng,
+                                       const X509_Time& not_before,
+                                       const X509_Time& not_after)
+   {
+   Key_Constraints constraints;
+   if(req.is_CA())
+      {
+      constraints = Key_Constraints(KEY_CERT_SIGN | CRL_SIGN);
+      }
+   else
+      {
+      std::unique_ptr<Public_Key> key(req.subject_public_key());
+      verify_cert_constraints_valid_for_key_type(*key, req.constraints());
+      constraints = req.constraints();
+      }
+
+   Extensions extensions;
+
+   extensions.add(
+      new Cert_Extension::Basic_Constraints(req.is_CA(), req.path_limit()),
+      true);
+
+   if(constraints != NO_CONSTRAINTS)
+      {
+      extensions.add(new Cert_Extension::Key_Usage(constraints), true);
+      }
+
+   extensions.add(new Cert_Extension::Authority_Key_ID(m_cert.subject_key_id()));
+   extensions.add(new Cert_Extension::Subject_Key_ID(req.raw_public_key()));
+
+   extensions.add(
+      new Cert_Extension::Subject_Alternative_Name(req.subject_alt_name()));
+
+   extensions.add(
+      new Cert_Extension::Extended_Key_Usage(req.ex_constraints()));
+
+   return make_cert(m_signer, rng, m_ca_sig_algo,
+                    req.raw_public_key(),
+                    not_before, not_after,
+                    m_cert.subject_dn(), req.subject_dn(),
+                    extensions);
+   }
+
+/*
+* Create a new certificate
+*/
+X509_Certificate X509_CA::make_cert(PK_Signer* signer,
+                                    RandomNumberGenerator& rng,
+                                    const AlgorithmIdentifier& sig_algo,
+                                    const std::vector<byte>& pub_key,
+                                    const X509_Time& not_before,
+                                    const X509_Time& not_after,
+                                    const X509_DN& issuer_dn,
+                                    const X509_DN& subject_dn,
+                                    const Extensions& extensions)
+   {
+   const size_t X509_CERT_VERSION = 3;
+   const size_t SERIAL_BITS = 128;
+
+   BigInt serial_no(rng, SERIAL_BITS);
+
+   // clang-format off
+   return X509_Certificate(X509_Object::make_signed(
+      signer, rng, sig_algo,
+      DER_Encoder().start_cons(SEQUENCE)
+         .start_explicit(0)
+            .encode(X509_CERT_VERSION-1)
+         .end_explicit()
+
+         .encode(serial_no)
+
+         .encode(sig_algo)
+         .encode(issuer_dn)
+
+         .start_cons(SEQUENCE)
+            .encode(not_before)
+            .encode(not_after)
+         .end_cons()
+
+         .encode(subject_dn)
+         .raw_bytes(pub_key)
+
+         .start_explicit(3)
+            .start_cons(SEQUENCE)
+               .encode(extensions)
+             .end_cons()
+         .end_explicit()
+      .end_cons()
+      .get_contents()
+      ));;
+   // clang-format on
+   }
+
+/*
+* Create a new, empty CRL
+*/
+X509_CRL X509_CA::new_crl(RandomNumberGenerator& rng,
+                          u32bit next_update) const
+   {
+   std::vector<CRL_Entry> empty;
+   return make_crl(empty, 1, next_update, rng);
+   }
+
+/*
+* Update a CRL with new entries
+*/
+X509_CRL X509_CA::update_crl(const X509_CRL& crl,
+                             const std::vector<CRL_Entry>& new_revoked,
+                             RandomNumberGenerator& rng,
+                             u32bit next_update) const
+   {
+   std::vector<CRL_Entry> revoked = crl.get_revoked();
+
+   std::copy(new_revoked.begin(), new_revoked.end(),
+             std::back_inserter(revoked));
+
+   return make_crl(revoked, crl.crl_number() + 1, next_update, rng);
+   }
+
+/*
+* Create a CRL
+*/
+X509_CRL X509_CA::make_crl(const std::vector<CRL_Entry>& revoked,
+                           u32bit crl_number, u32bit next_update,
+                           RandomNumberGenerator& rng) const
+   {
+   const size_t X509_CRL_VERSION = 2;
+
+   if(next_update == 0)
+      next_update = timespec_to_u32bit("7d");
+
+   // Totally stupid: ties encoding logic to the return of std::time!!
+   auto current_time = std::chrono::system_clock::now();
+   auto expire_time = current_time + std::chrono::seconds(next_update);
+
+   Extensions extensions;
+   extensions.add(
+      new Cert_Extension::Authority_Key_ID(m_cert.subject_key_id()));
+   extensions.add(new Cert_Extension::CRL_Number(crl_number));
+
+   // clang-format off
+   const std::vector<byte> crl = X509_Object::make_signed(
+      m_signer, rng, m_ca_sig_algo,
+      DER_Encoder().start_cons(SEQUENCE)
+         .encode(X509_CRL_VERSION-1)
+         .encode(m_ca_sig_algo)
+         .encode(m_cert.issuer_dn())
+         .encode(X509_Time(current_time))
+         .encode(X509_Time(expire_time))
+         .encode_if(revoked.size() > 0,
+              DER_Encoder()
+                 .start_cons(SEQUENCE)
+                    .encode_list(revoked)
+                 .end_cons()
+            )
+         .start_explicit(0)
+            .start_cons(SEQUENCE)
+               .encode(extensions)
+            .end_cons()
+         .end_explicit()
+      .end_cons()
+      .get_contents());
+   // clang-format on
+
+   return X509_CRL(crl);
+   }
+
+/*
+* Return the CA's certificate
+*/
+X509_Certificate X509_CA::ca_certificate() const
+   {
+   return m_cert;
+   }
+
+/*
+* Choose a signing format for the key
+*/
+PK_Signer* choose_sig_format(const Private_Key& key,
+                             RandomNumberGenerator& rng,
+                             const std::string& hash_fn,
+                             AlgorithmIdentifier& sig_algo)
+   {
+   const std::string algo_name = key.algo_name();
+
+   std::unique_ptr<HashFunction> hash(HashFunction::create(hash_fn));
+   if(!hash)
+      throw Algorithm_Not_Found(hash_fn);
+
+   if(key.max_input_bits() < hash->output_length() * 8)
+      throw Invalid_Argument("Key is too small for chosen hash function");
+
+   std::string padding;
+   if(algo_name == "RSA")
+      {
+      padding = "EMSA3";
+      }
+   else if(algo_name == "DSA" || algo_name == "ECDSA" || algo_name == "ECGDSA" || algo_name == "ECKCDSA")
+      {
+      padding = "EMSA1";
+      }
+   else
+      {
+      throw Invalid_Argument("Unknown X.509 signing key type: " + algo_name);
+      }
+
+   const Signature_Format format = (key.message_parts() > 1) ? DER_SEQUENCE : IEEE_1363;
+
+   padding = padding + "(" + hash->name() + ")";
+
+   sig_algo.oid = OIDS::lookup(algo_name + "/" + padding);
+   sig_algo.parameters = key.algorithm_identifier().parameters;
+
+   return new PK_Signer(key, rng, padding, format);
+   }
+
+}