Export X.509 certificates to ffi and python

Missing path validation, probably other things

5 files changed, 396 insertions, 56 deletions

diff --git a/src/lib/cert/x509/key_constraint.h b/src/lib/cert/x509/key_constraint.h
index 22ae7a32e..3509b6868 100644
--- a/src/lib/cert/x509/key_constraint.h
+++ b/src/lib/cert/x509/key_constraint.h
@@ -14,6 +14,7 @@ namespace Botan {
 
 /**
 * X.509v3 Key Constraints.
+* If updating update copy in ffi.h
 */
 enum Key_Constraints {
    NO_CONSTRAINTS     = 0,
diff --git a/src/lib/ffi/ffi.cpp b/src/lib/ffi/ffi.cpp
index 606415575..608bd291b 100644
--- a/src/lib/ffi/ffi.cpp
+++ b/src/lib/ffi/ffi.cpp
@@ -13,6 +13,8 @@
 #include <botan/pbkdf.h>
 #include <botan/version.h>
 #include <botan/pkcs8.h>
+#include <botan/x509cert.h>
+#include <botan/data_src.h>
 #include <botan/pubkey.h>
 #include <botan/data_src.h>
 #include <botan/hex.h>
@@ -161,12 +163,14 @@ BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_sign_struct, Botan::PK_Signer, 0x1AF0C39F);
 BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_verify_struct, Botan::PK_Verifier, 0x2B91F936);
 BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_ka_struct, Botan::PK_Key_Agreement, 0x2939CAB1);
 
+BOTAN_FFI_DECLARE_STRUCT(botan_x509_cert_struct, Botan::X509_Certificate, 0x8F628937);
+
 /*
 * Versioning
 */
 uint32_t botan_ffi_api_version()
    {
-   return 20150210; // should match value in info.txt
+   return BOTAN_HAS_FFI;
    }
 
 const char* botan_version_string()
@@ -636,7 +640,6 @@ int botan_kdf(const char* kdf_algo,
    return -1;
    }
 
-#if defined(BOTAN_HAS_BCRYPT)
 int botan_bcrypt_generate(uint8_t* out, size_t* out_len,
                           const char* pass,
                           botan_rng_t rng_obj, size_t wf,
@@ -654,9 +657,13 @@ int botan_bcrypt_generate(uint8_t* out, size_t* out_len,
       if(wf < 2 || wf > 30)
          throw std::runtime_error("Bad bcrypt work factor " + std::to_string(wf));
 
+#if defined(BOTAN_HAS_BCRYPT)
       Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
       const std::string bcrypt = Botan::generate_bcrypt(pass, rng, wf);
       return write_str_output(out, out_len, bcrypt);
+#else
+      return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
       }
    catch(std::exception& e)
       {
@@ -674,6 +681,7 @@ int botan_bcrypt_is_valid(const char* pass, const char* hash)
    {
    try
       {
+      #define BOTAN_
       if(Botan::check_bcrypt(pass, hash))
          return 0; // success
       return 1;
@@ -690,8 +698,6 @@ int botan_bcrypt_is_valid(const char* pass, const char* hash)
    return BOTAN_FFI_ERROR_EXCEPTION_THROWN;
    }
 
-#endif
-
 int botan_privkey_create_rsa(botan_privkey_t* key_obj, botan_rng_t rng_obj, size_t n_bits)
    {
    try
@@ -1137,5 +1143,146 @@ int botan_pk_op_key_agreement(botan_pk_op_ka_t op,
       });
    }
 
+int botan_x509_cert_load_file(botan_x509_cert_t* cert_obj, const char* cert_path)
+   {
+   try
+      {
+      if(!cert_obj || !cert_path)
+         return -1;
+
+      std::unique_ptr<Botan::X509_Certificate> c(new Botan::X509_Certificate(cert_path));
+
+      if(c)
+         {
+         *cert_obj = new botan_x509_cert_struct(c.release());
+         return 0;
+         }
+      }
+   catch(std::exception& e)
+      {
+      log_exception(BOTAN_CURRENT_FUNCTION, e.what());
+      }
+   catch(...)
+      {
+      log_exception(BOTAN_CURRENT_FUNCTION, "unknown");
+      }
+
+   return -2;
+   }
+
+int botan_x509_cert_load(botan_x509_cert_t* cert_obj, const uint8_t cert_bits[], size_t cert_bits_len)
+   {
+   try
+      {
+      if(!cert_obj || !cert_bits)
+         return -1;
+
+      Botan::DataSource_Memory bits(cert_bits, cert_bits_len);
+
+      std::unique_ptr<Botan::X509_Certificate> c(new Botan::X509_Certificate(bits));
+
+      if(c)
+         {
+         *cert_obj = new botan_x509_cert_struct(c.release());
+         return 0;
+         }
+      }
+   catch(std::exception& e)
+      {
+      log_exception(BOTAN_CURRENT_FUNCTION, e.what());
+      }
+   catch(...)
+      {
+      log_exception(BOTAN_CURRENT_FUNCTION, "unknown");
+      }
+
+   return -2;
+
+   }
+
+int botan_x509_cert_destroy(botan_x509_cert_t cert)
+   {
+   delete cert;
+   return 0;
+   }
+
+int botan_x509_cert_get_time_starts(botan_x509_cert_t cert, char out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_str_output(out, out_len, cert.start_time()); });
+   }
+
+int botan_x509_cert_get_time_expires(botan_x509_cert_t cert, char out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_str_output(out, out_len, cert.end_time()); });
+   }
+
+int botan_x509_cert_get_serial_number(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_vec_output(out, out_len, cert.serial_number()); });
+   }
+
+int botan_x509_cert_get_fingerprint(botan_x509_cert_t cert, const char* hash, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_str_output(out, out_len, cert.fingerprint(hash)); });
+   }
+
+int botan_x509_cert_get_authority_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_vec_output(out, out_len, cert.authority_key_id()); });
+   }
+
+int botan_x509_cert_get_subject_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_vec_output(out, out_len, cert.subject_key_id()); });
+   }
+
+int botan_x509_cert_get_public_key_bits(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_vec_output(out, out_len, cert.subject_public_key_bits()); });
+   }
+
+
+/*
+int botan_x509_cert_path_verify(botan_x509_cert_t cert, const char* dir)
+{
+}
+*/
+
+int botan_x509_cert_get_public_key(botan_x509_cert_t cert, botan_pubkey_t* key)
+   {
+   *key = nullptr;
+   return -1;
+   //return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_vec_output(out, out_len, cert.subject_public_key_bits()); });
+   }
+
+int botan_x509_cert_get_issuer_dn(botan_x509_cert_t cert,
+                                  const char* key, size_t index,
+                                  uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_str_output(out, out_len, cert.issuer_info(key).at(index)); });
+   }
+
+int botan_x509_cert_get_subject_dn(botan_x509_cert_t cert,
+                                   const char* key, size_t index,
+                                   uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_str_output(out, out_len, cert.subject_info(key).at(index)); });
+   }
+
+int botan_x509_cert_to_string(botan_x509_cert_t cert, char out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, { return write_str_output(out, out_len, cert.to_string()); });
+   }
+
+int botan_x509_cert_allowed_usage(botan_x509_cert_t cert, unsigned int key_usage)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, {
+      const Botan::Key_Constraints k = static_cast<Botan::Key_Constraints>(key_usage);
+      if(cert.allowed_usage(k))
+         return 0;
+      return 1;
+      });
+   }
+
 }
 
diff --git a/src/lib/ffi/ffi.h b/src/lib/ffi/ffi.h
index a516529b4..1402ec129 100644
--- a/src/lib/ffi/ffi.h
+++ b/src/lib/ffi/ffi.h
@@ -1,4 +1,5 @@
 /*
+* FFI (C89 API)
 * (C) 2015 Jack Lloyd
 *
 * Botan is released under the Simplified BSD License (see license.txt)
@@ -11,19 +12,46 @@
 extern "C" {
 #endif
 
-#include <botan/build.h>
-#include <stdint.h>
-#include <stddef.h>
-
 /*
+This header exports some of botan's functionality via a C89 interface.  The API
+is intended to be as easy as possible to call from other languages, which often
+have easy ways to call C, because C. But some C code is easier to deal with than
+others, so to make things easy this API follows a few simple rules:
+
+- All interactions are via pointers to opaque structs. No need to worry about
+  structure padding issues and the like.
+
+- All functions return an int error code (except the version calls, which are
+  assumed to always have something to say).
+
+- No ownership of memory transfers across the API boundary. The API will write
+  to buffers provided by the caller, or return opaque pointers which may not be
+  dereferenced.
+
+- If exporting a value (a string or a blob) the function takes a pointer to the
+  output array and a read/write pointer to the length. If it is insufficient, an
+  error is returned. So passing nullptr/0 
+
+This API is uesd by the Python and OCaml bindings via those languages respective
+ctypes libraries.
+
+The API is not currently documented, nor should it be considered stable. It is
+buggy as heck, most likely. However the goal is to provide a long term API
+usable for language bindings, or for use by systems written in C. Suggestions on
+how to provide the cleanest API for such users would be most welcome.
+
 * TODO:
 * - Better error reporting
-* - User callback for exception logging
+* - User callback for exception logging?
 * - Doxygen comments for all functions/params
 * - X.509 certs and PKIX path validation goo
 * - TLS
 */
 
+#include <botan/build.h>
+#include <stdint.h>
+#include <stddef.h>
+
 /*
 * Versioning
 */
@@ -37,11 +65,30 @@ BOTAN_DLL uint32_t botan_version_datestamp();
 
 /*
 * Error handling
+*
+* Some way of exporting these values to other languages would be useful
+
+ THIS FUNCTION ASSUMES BOTH ARGUMENTS ARE LITERAL STRINGS
+ so it retains only the pointers and does not make a copy.
+
+int botan_make_error(const char* msg, const char* func, int line);
+* This value is returned to callers ^^
+
+ normally called like
+   return botan_make_error(BOTAN_ERROR_STRING_NOT_IMPLEMENTED, BOTAN_FUNCTION, __LINE__);
+
+#define botan_make_error_inf(s) return botan_make_error(s, BOTAN_FUNCTION, __LINE__);
+
+*
+* Later call:
+* const char* botan_get_error_str(int);
+* To recover the msg, func, and line
+
 */
 #define BOTAN_FFI_ERROR_EXCEPTION_THROWN (-20)
 #define BOTAN_FFI_ERROR_BAD_FLAG (-30)
 #define BOTAN_FFI_ERROR_NULL_POINTER (-31)
-#define BOTAN_FFI_ERROR_NULL_POINTER (-31)
+#define BOTAN_FFI_ERROR_NOT_IMPLEMENTED (-40)
 
 //const char* botan_error_description(int err);
 
@@ -53,6 +100,9 @@ BOTAN_DLL int botan_same_mem(const uint8_t* x, const uint8_t* y, size_t len);
 #define BOTAN_FFI_HEX_LOWER_CASE 1
 
 BOTAN_DLL int botan_hex_encode(const uint8_t* x, size_t len, char* out, uint32_t flags);
+// TODO: botan_hex_decode
+// TODO: botan_base64_encode
+// TODO: botan_base64_decode
 
 /*
 * RNG
@@ -198,8 +248,6 @@ BOTAN_DLL int botan_kdf(const char* kdf_algo,
 /*
 * Bcrypt
 */
-#if defined(BOTAN_HAS_BCRYPT)
-
 BOTAN_DLL int botan_bcrypt_generate(uint8_t* out, size_t* out_len,
                                     const char* pass,
                                     botan_rng_t rng,
@@ -213,8 +261,6 @@ BOTAN_DLL int botan_bcrypt_generate(uint8_t* out, size_t* out_len,
 */
 BOTAN_DLL int botan_bcrypt_is_valid(const char* pass, const char* hash);
 
-#endif
-
 /*
 * Public/private key creation, import, ...
 */
@@ -359,6 +405,63 @@ BOTAN_DLL int botan_pk_op_key_agreement(botan_pk_op_ka_t op,
                                         const uint8_t other_key[], size_t other_key_len,
                                         const uint8_t salt[], size_t salt_len);
 
+
+typedef struct botan_x509_cert_struct* botan_x509_cert_t;
+BOTAN_DLL int botan_x509_cert_load(botan_x509_cert_t* cert_obj, const uint8_t cert[], size_t cert_len);
+BOTAN_DLL int botan_x509_cert_load_file(botan_x509_cert_t* cert_obj, const char* filename);
+BOTAN_DLL int botan_x509_cert_destroy(botan_x509_cert_t cert);
+
+BOTAN_DLL int botan_x509_cert_gen_selfsigned(botan_x509_cert_t* cert,
+                                             botan_privkey_t key,
+                                             botan_rng_t rng,
+                                             const char* common_name,
+                                             const char* org_name);
+
+// TODO: return botan_time_struct instead
+BOTAN_DLL int botan_x509_cert_get_time_starts(botan_x509_cert_t cert, char out[], size_t* out_len);
+BOTAN_DLL int botan_x509_cert_get_time_expires(botan_x509_cert_t cert, char out[], size_t* out_len);
+
+BOTAN_DLL int botan_x509_cert_get_fingerprint(botan_x509_cert_t cert, const char* hash, uint8_t out[], size_t* out_len);
+
+BOTAN_DLL int botan_x509_cert_get_serial_number(botan_x509_cert_t cert, uint8_t out[], size_t* out_len);
+BOTAN_DLL int botan_x509_cert_get_authority_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len);
+BOTAN_DLL int botan_x509_cert_get_subject_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len);
+
+BOTAN_DLL int botan_x509_cert_path_verify(botan_x509_cert_t cert,
+                                          const char* ca_dir);
+
+BOTAN_DLL int botan_x509_cert_get_public_key_bits(botan_x509_cert_t cert,
+                                                  uint8_t out[], size_t* out_len);
+
+BOTAN_DLL int botan_x509_cert_get_public_key(botan_x509_cert_t cert, botan_pubkey_t* key);
+
+BOTAN_DLL int botan_x509_cert_get_issuer_dn(botan_x509_cert_t cert,
+                                            const char* key, size_t index,
+                                            uint8_t out[], size_t* out_len);
+
+
+BOTAN_DLL int botan_x509_cert_get_subject_dn(botan_x509_cert_t cert,
+                                             const char* key, size_t index,
+                                             uint8_t out[], size_t* out_len);
+
+BOTAN_DLL int botan_x509_cert_to_string(botan_x509_cert_t cert, char out[], size_t* out_len);
+
+// Must match values of Key_Constraints in key_constraints.h
+enum botan_x509_cert_key_constraints {
+   NO_CONSTRAINTS     = 0,
+   DIGITAL_SIGNATURE  = 32768,
+   NON_REPUDIATION    = 16384,
+   KEY_ENCIPHERMENT   = 8192,
+   DATA_ENCIPHERMENT  = 4096,
+   KEY_AGREEMENT      = 2048,
+   KEY_CERT_SIGN      = 1024,
+   CRL_SIGN           = 512,
+   ENCIPHER_ONLY      = 256,
+   DECIPHER_ONLY      = 128
+};
+
+BOTAN_DLL int botan_x509_cert_allowed_usage(botan_x509_cert_t cert, unsigned int key_usage);
+
 /*
 * TLS (WIP)
 */
@@ -368,6 +471,7 @@ typedef struct botan_tls_session_struct* botan_tls_session_t;
 
 BOTAN_DLL int botan_tls_session_get_version(botan_tls_session_t* session, uint16_t* tls_version);
 BOTAN_DLL int botan_tls_session_get_ciphersuite(botan_tls_session_t* session, uint16_t* ciphersuite);
+BOTAN_DLL int botan_tls_session
 // TODO: peer certs, validation, ...
 
 typedef struct botan_tls_channel_struct* botan_tls_channel_t;
@@ -401,7 +505,6 @@ BOTAN_DLL int botan_tls_channel_close(botan_tls_channel_t chan);
 BOTAN_DLL int botan_tls_channel_destroy(botan_tls_channel_t chan);
 
 #endif
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/lib/ffi/info.txt b/src/lib/ffi/info.txt
index 94a804ba0..52885e8e1 100644
--- a/src/lib/ffi/info.txt
+++ b/src/lib/ffi/info.txt
@@ -6,6 +6,7 @@ filters
 kdf
 pbkdf
 pubkey
+x509
 auto_rng
 system_rng
 </requires>
diff --git a/src/python/botan.py b/src/python/botan.py
index a28f3ddb0..054130b80 100755
--- a/src/python/botan.py
+++ b/src/python/botan.py
@@ -29,6 +29,40 @@ botan_api_rev = botan.botan_ffi_api_version()
 if botan_api_rev != expected_api_rev:
     raise Exception("Bad botan API rev got %d expected %d" % (botan_api_rev, expected_api_rev))
 
+# Internal utilities
+def _call_fn_returning_string(guess, fn):
+
+    buf = create_string_buffer(guess)
+    buf_len = c_size_t(len(buf))
+
+    rc = fn(buf, byref(buf_len))
+    if rc < 0:
+        if buf_len.value > len(buf):
+            #print("Calling again with %d" % (buf_len.value))
+            return _call_fn_returning_string(buf_len.value, fn)
+        else:
+            raise Exception("Call failed: %d" % (rc))
+
+    assert buf_len.value <= len(buf)
+    return buf.raw[0:buf_len.value]
+
+def _call_fn_returning_vec(guess, fn):
+
+    buf = create_string_buffer(guess)
+    buf_len = c_size_t(len(buf))
+
+    rc = fn(buf, byref(buf_len))
+    if rc < 0:
+        if buf_len.value > len(buf):
+            #print("Calling again with %d" % (buf_len.value))
+            return _call_fn_returning_vec(buf_len.value, fn)
+        else:
+            raise Exception("Call failed: %d" % (rc))
+
+    assert buf_len.value <= len(buf)
+    return buf.raw[0:buf_len.value]
+
+
 """
 Versions
 """
@@ -57,7 +91,7 @@ class rng(object):
             rc = botan.botan_rng_init(byref(self.rng), rng_type)
         else:
             rc = botan.botan_rng_init(byref(self.rng), rng_type.encode('ascii'))
-                
+
         if rc != 0 or self.rng is None:
             raise Exception("No rng " + algo + " for you!")
 
@@ -256,7 +290,6 @@ class cipher(object):
 
 """
 Bcrypt
-TODO: might not be enabled - handle that gracefully!
 """
 def bcrypt(passwd, rng, work_factor = 10):
     botan.botan_bcrypt_generate.argtypes = [POINTER(c_char), POINTER(c_size_t),
@@ -322,12 +355,7 @@ class public_key(object):
 
     def algo_name(self):
         botan.botan_pubkey_algo_name.argtypes = [c_void_p, POINTER(c_char), POINTER(c_size_t)]
-
-        buf = create_string_buffer(64)
-        buf_len = c_size_t(len(buf))
-        botan.botan_pubkey_algo_name(self.pubkey, buf, byref(buf_len))
-        assert buf_len.value <= len(buf)
-        return buf.raw[0:buf_len.value]
+        return _call_fn_returning_string(32, lambda b,bl: botan.botan_pubkey_algo_name(self.pubkey, b, bl))
 
     def fingerprint(self, hash = 'SHA-256'):
         botan.botan_pubkey_fingerprint.argtypes = [c_void_p, c_char_p,
@@ -338,7 +366,7 @@ class public_key(object):
         buf_len = c_size_t(n)
         if sys.version_info[0] > 2:
             hash = hash.encode('utf-8')
-    
+
         botan.botan_pubkey_fingerprint(self.pubkey, hash, buf, byref(buf_len))
         return hexlify(buf[0:buf_len.value])
 
@@ -385,7 +413,6 @@ class private_key(object):
             botan.botan_privkey_export(self.privkey, buf, byref(buf_len))
         return buf[0:buf_len.value]
 
-
 class pk_op_encrypt(object):
     def __init__(self, key, padding):
         botan.botan_pk_op_encrypt_create.argtypes = [c_void_p, c_void_p, c_char_p, c_uint32]
@@ -417,7 +444,7 @@ class pk_op_encrypt(object):
         #print("encrypt: outbuf_sz.value=%d" % outbuf_sz.value)
         return outbuf.raw[0:outbuf_sz.value]
 
-    
+
 class pk_op_decrypt(object):
     def __init__(self, key, padding):
         botan.botan_pk_op_decrypt_create.argtypes = [c_void_p, c_void_p, c_char_p, c_uint32]
@@ -534,17 +561,68 @@ class pk_op_key_agreement(object):
                                             other, len(other), salt, len(salt))
         return outbuf.raw[0:outbuf_sz.value]
 
+class x509_cert(object):
+    def __init__(self, filename):
+        botan.botan_x509_cert_load_file.argtypes = [POINTER(c_void_p), c_char_p]
+        self.x509_cert = c_void_p(0)
+        if sys.version_info[0] > 2:
+            filename = cast(filename, c_char_p)
+        botan.botan_x509_cert_load_file(byref(self.x509_cert), filename)
+
+    def __del__(self):
+        botan.botan_x509_cert_destroy.argtypes = [c_void_p]
+        botan.botan_x509_cert_destroy(self.x509_cert)
+
+    # TODO: have these convert to a python datetime
+    def time_starts(self):
+        botan.botan_x509_cert_get_time_starts.argtypes = [c_void_p, POINTER(c_char), POINTER(c_size_t)]
+        return _call_fn_returning_string(16, lambda b,bl: botan.botan_x509_cert_get_time_starts(self.x509_cert, b, bl))
+
+    def time_expires(self):
+        botan.botan_x509_cert_get_time_expires.argtypes = [c_void_p, POINTER(c_char), POINTER(c_size_t)]
+        return _call_fn_returning_string(16, lambda b,bl: botan.botan_x509_cert_get_time_expires(self.x509_cert, b, bl))
+
+    def to_string(self):
+        botan.botan_x509_cert_to_string.argtypes = [c_void_p, POINTER(c_char), POINTER(c_size_t)]
+        return _call_fn_returning_string(0, lambda b,bl: botan.botan_x509_cert_to_string(self.x509_cert, b, bl))
+
+    def fingerprint(self, hash_algo = 'SHA-256'):
+        botan.botan_x509_cert_get_fingerprint.argtypes = [c_void_p, c_char_p,
+                                                          POINTER(c_char), POINTER(c_size_t)]
+
+        n = hash_function(hash_algo).output_length() * 3
+        if sys.version_info[0] > 2:
+            hash_algo = hash_algo.encode('utf-8')
+
+        return _call_fn_returning_string(n, lambda b,bl: botan.botan_x509_cert_get_fingerprint(self.x509_cert, hash_algo, b, bl))
+
+    def serial_number(self):
+        botan.botan_x509_cert_get_serial_number.argtypes = [c_void_p, POINTER(c_char), POINTER(c_size_t)]
+        return _call_fn_returning_vec(0, lambda b,bl: botan.botan_x509_cert_get_serial_number(self.x509_cert, b, bl))
+
+    def authority_key_id(self):
+        botan.botan_x509_cert_get_authority_key_id.argtypes = [c_void_p, POINTER(c_char), POINTER(c_size_t)]
+        return _call_fn_returning_vec(0, lambda b,bl: botan.botan_x509_cert_get_authority_key_id(self.x509_cert, b, bl))
+
+    def subject_key_id(self):
+        botan.botan_x509_cert_get_subject_key_id.argtypes = [c_void_p, POINTER(c_char), POINTER(c_size_t)]
+        return _call_fn_returning_vec(0, lambda b,bl: botan.botan_x509_cert_get_subject_key_id(self.x509_cert, b, bl))
+
+    def subject_public_key_bits(self):
+        botan.botan_x509_cert_get_public_key_bits.argtypes = [c_void_p, POINTER(c_char), POINTER(c_size_t)]
+        return _call_fn_returning_vec(0, lambda b,bl: botan.botan_x509_cert_get_public_key_bits(self.x509_cert, b, bl))
+
+
 """
 Tests and examples
 """
 def test():
-    r = rng("user")
 
+    r = rng("user")
 
     print("\n%s" % version_string().decode('utf-8'))
     print("v%d.%d.%d\n" % (version_major(), version_minor(), version_patch()))
 
-
     print("KDF2(SHA-1)   %s" %
           hexlify(kdf('KDF2(SHA-1)'.encode('ascii'), unhexlify('701F3480DFE95F57941F804B1B2413EF'), 7,
                       unhexlify('55A4E9DD5F4CA2EF82'))
@@ -559,18 +637,16 @@ def test():
     print("good output   %s\n" %
           '59B2B1143B4CB1059EC58D9722FB1C72471E0D85C6F7543BA5228526375B0127')
 
-
-        
     (salt,iterations,psk) = pbkdf_timed('PBKDF2(SHA-256)'.encode('ascii'),
                                         'xyz'.encode('utf-8'), 32, 200)
 
-    if sys.version_info[0] < 3:        
+    if sys.version_info[0] < 3:
         print("PBKDF2(SHA-256) x=timed, y=iterated; salt = %s (len=%d)  #iterations = %d\n" %
               (hexlify(salt), len(salt), iterations)   )
     else:
         print("PBKDF2(SHA-256) x=timed, y=iterated; salt = %s (len=%d)  #iterations = %d\n" %
               (hexlify(salt).decode('ascii'), len(salt), iterations)   )
-        
+
     print('x %s' % hexlify(psk).decode('utf-8'))
     print('y %s\n' %
           (hexlify(pbkdf('PBKDF2(SHA-256)'.encode('utf-8'),
@@ -579,7 +655,7 @@ def test():
     hmac = message_authentication_code('HMAC(SHA-256)'.encode('ascii'))
     hmac.set_key(unhexlify('0102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F20'))
     hmac.update(unhexlify('616263'))
-    
+
     hmac_output = hmac.final()
 
     if hmac_output != unhexlify('A21B1F5D4CF4F73A4DD939750F7A066A7F98CC131CB16A6692759021CFAB8181'):
@@ -587,7 +663,7 @@ def test():
         print("vs good: \tA21B1F5D4CF4F73A4DD939750F7A066A7F98CC131CB16A6692759021CFAB8181");
     else:
         print("HMAC output (good): %s\n" % hexlify(hmac_output).decode('utf-8'))
-    
+
     print("rng output:\n\t%s\n\t%s\n\t%s\n" %
           (hexlify(r.get(42)).decode('utf-8'),
            hexlify(r.get(13)).decode('utf-8'),
@@ -645,7 +721,7 @@ def test():
     rsapriv = private_key('rsa', 1536, r)
 
     rsapub = rsapriv.get_public_key()
-    
+
     print("rsapub %s/SHA-1 fingerprint: %s (estimated strength %s)" %
           (rsapub.algo_name().decode('utf-8'), rsapub.fingerprint("SHA-1").decode('utf-8'),
            rsapub.estimated_strength()
@@ -656,7 +732,7 @@ def test():
     enc = pk_op_encrypt(rsapub, "EME1(SHA-256)".encode('utf-8'))
 
     ctext = enc.encrypt('foof'.encode('utf-8'), r)
-    print("ptext  \'%s\'" % 'foof') 
+    print("ptext  \'%s\'" % 'foof')
     print("ctext   \'%s\'" % hexlify(ctext).decode('utf-8'))
     print("decrypt \'%s\'\n" % dec.decrypt(ctext).decode('utf-8'))
 
@@ -669,7 +745,7 @@ def test():
     r.reseed(200)
     print("EMSA4(SHA-384) signature: %s" % hexlify(sig).decode('utf-8'))
 
-    
+
     verify = pk_op_verify(rsapub, 'EMSA4(SHA-384)'.encode('utf-8'))
 
     verify.update('mess'.encode('utf-8'))
@@ -683,32 +759,44 @@ def test():
     verify.update('message'.encode('utf-8'))
     print("good sig accepted? %s\n" % verify.check_signature(sig))
 
-    dh_grp = 'secp256r1'.encode('utf-8')
-    #dh_grp = 'curve25519'.encode('utf-8')
-    dh_kdf = 'KDF2(SHA-384)'.encode('utf-8')
-    a_dh_priv = private_key('ecdh', dh_grp, r)
-    a_dh_pub = a_dh_priv.get_public_key()
+    for dh_grps in ['secp256r1', 'curve25519']:
+        dh_grp = dh_grps.encode('utf-8')
+        dh_kdf = 'KDF2(SHA-384)'.encode('utf-8')
+        a_dh_priv = private_key('ecdh', dh_grp, r)
+        a_dh_pub = a_dh_priv.get_public_key()
+
+        b_dh_priv = private_key('ecdh', dh_grp, r)
+        b_dh_pub = b_dh_priv.get_public_key()
+
+        a_dh = pk_op_key_agreement(a_dh_priv, dh_kdf)
+        b_dh = pk_op_key_agreement(b_dh_priv, dh_kdf)
+
+        print("ecdh %s pubs:\n  %s\n  %s\n" %
+              (dh_grps,
+               hexlify(a_dh.public_value()).decode('utf-8'),
+               hexlify(b_dh.public_value()).decode('utf-8')))
 
-    b_dh_priv = private_key('ecdh', dh_grp, r)
-    b_dh_pub = b_dh_priv.get_public_key()
+        a_key = a_dh.agree(b_dh.public_value(), 20, 'salt'.encode('utf-8'))
+        b_key = b_dh.agree(a_dh.public_value(), 20, 'salt'.encode('utf-8'))
 
-    a_dh = pk_op_key_agreement(a_dh_priv, dh_kdf)
-    b_dh = pk_op_key_agreement(b_dh_priv, dh_kdf)
+        print("ecdh %s shared:\n  %s\n  %s\n" %
+              (dh_grps, hexlify(a_key).decode('utf-8'), hexlify(b_key).decode('utf-8')))
 
-    print("ecdh pubs:\n  %s\n  %s\n" %
-          (hexlify(a_dh.public_value()).decode('utf-8'),
-           hexlify(b_dh.public_value()).decode('utf-8')))
+    cert = x509_cert("src/tests/data/ecc/CSCA.CSCA.csca-germany.1.crt")
+    print(cert.fingerprint("SHA-1"))
+    print("32:42:1C:C3:EC:54:D7:E9:43:EC:51:F0:19:23:BD:85:1D:F2:1B:B9")
 
-    a_key = a_dh.agree(b_dh.public_value(), 20, 'salt'.encode('utf-8'))
-    b_key = b_dh.agree(a_dh.public_value(), 20, 'salt'.encode('utf-8'))
+    print(cert.time_starts())
+    print(cert.time_expires())
 
-    print("ecdh shared:\n  %s\n  %s\n" %
-          (hexlify(a_key).decode('utf-8'), hexlify(b_key).decode('utf-8')))
+    print(hexlify(cert.serial_number()))
+    print(hexlify(cert.authority_key_id()))
+    print(hexlify(cert.subject_key_id()))
+    print(hexlify(cert.subject_public_key_bits()))
 
+    print(cert.to_string())
 
-    #f = open('key.ber','wb')
-    #f.write(blob)
-    #f.close()
+    return
 
 
 def main(args = None):