Add a test for HTTPS serving

Uses a nice new module I created to wrap OpenSSl's insance API for
creating certificates.

setup/build_environment.py

@@ -122,6 +122,7 @@ icu_lib_dirs = []
 zlib_inc_dirs = []
 zlib_lib_dirs = []
 zlib_libs = ['z']
+openssl_inc_dirs, openssl_lib_dirs = [], []
 ICU = sw = ''
 
 QT_DLLS = ['Qt5' + x for x in (
@@ -149,6 +150,9 @@ if iswindows:
     icu_inc_dirs = [os.path.join(ICU, 'source', 'common'), os.path.join(ICU,
         'source', 'i18n')]
     icu_lib_dirs = [os.path.join(ICU, 'source', 'lib')]
+    SSL = os.environ.get('OPENSSL_DIR', os.path.join(prefix, 'private', 'openssl'))
+    openssl_inc_dirs = [os.path.join(SSL, 'include')]
+    openssl_lib_dirs = [os.path.join(SSL, 'lib')]
     sqlite_inc_dirs = [sw_inc_dir]
     chmlib_inc_dirs = consolidate('CHMLIB_INC_DIR', os.path.join(prefix,
         'build', 'chmlib-0.40', 'src'))

setup/extensions.py

@@ -10,12 +10,13 @@ import textwrap, os, shlex, subprocess, glob, shutil, re, sys
 from distutils import sysconfig
 
 from setup import Command, islinux, isbsd, isosx, SRC, iswindows, __version__
-from setup.build_environment import (chmlib_inc_dirs,
-        podofo_inc, podofo_lib, podofo_error, pyqt, NMAKE, QMAKE,
-        msvc, win_inc, win_lib, magick_inc_dirs, magick_lib_dirs,
-        magick_libs, chmlib_lib_dirs, sqlite_inc_dirs, icu_inc_dirs,
-        icu_lib_dirs, ft_libs, ft_lib_dirs, ft_inc_dirs, cpu_count,
-        zlib_libs, zlib_lib_dirs, zlib_inc_dirs, is64bit, glib_flags, fontconfig_flags)
+from setup.build_environment import (
+    chmlib_inc_dirs, podofo_inc, podofo_lib, podofo_error, pyqt, NMAKE, QMAKE,
+    msvc, win_inc, win_lib, magick_inc_dirs, magick_lib_dirs, magick_libs,
+    chmlib_lib_dirs, sqlite_inc_dirs, icu_inc_dirs, icu_lib_dirs, ft_libs,
+    ft_lib_dirs, ft_inc_dirs, cpu_count, zlib_libs, zlib_lib_dirs,
+    zlib_inc_dirs, is64bit, glib_flags, fontconfig_flags, openssl_inc_dirs,
+    openssl_lib_dirs)
 from setup.parallel_build import create_job, parallel_build
 isunix = islinux or isosx or isbsd
 
@@ -86,6 +87,15 @@ extensions = [
         libraries=[] if iswindows else ['m']
         ),
 
+    Extension('certgen',
+        ['calibre/utils/certgen.c'],
+        libraries=['libeay32'] if iswindows else ['crypto'],
+        # Apple has deprecated openssl in OSX, so we need this, until we
+        # build our own private copy of openssl
+        cflags=['-Wno-deprecated-declarations'] if isosx else [],
+        inc_dirs=openssl_inc_dirs, lib_dirs=openssl_lib_dirs,
+        ),
+
     Extension('html',
         ['calibre/gui2/tweak_book/editor/syntax/html.c'],
         ),

src/calibre/constants.py

@@ -146,6 +146,7 @@ class Plugins(collections.Mapping):
                 'bzzdec',
                 'matcher',
                 'tokenizer',
+                'certgen',
             ]
         if iswindows:
             plugins.extend(['winutil', 'wpd', 'winfonts'])

src/calibre/srv/loop.py

@@ -156,7 +156,7 @@ class Connection(object):
 
     def do_ssl_handshake(self, event):
         try:
-            self._sslobj.do_handshake()
+            self.socket._sslobj.do_handshake()
         except ssl.SSLWantReadError:
             self.set_state(READ, self.do_ssl_handshake)
         except ssl.SSLWantWriteError:

src/calibre/srv/tests/loop.py

@@ -0,0 +1,41 @@
+#!/usr/bin/env python2
+# vim:fileencoding=utf-8
+from __future__ import (unicode_literals, division, absolute_import,
+                        print_function)
+
+__license__ = 'GPL v3'
+__copyright__ = '2015, Kovid Goyal <kovid at kovidgoyal.net>'
+
+import httplib, ssl, os
+from unittest import skipIf
+
+try:
+    from calibre.utils.certgen import create_server_cert
+except ImportError:
+    create_server_cert = None
+
+from calibre.srv.tests.base import BaseTest, TestServer
+from calibre.ptempfile import TemporaryDirectory
+
+HOST = 'localhost.test'
+
+class LoopTest(BaseTest):
+
+    @skipIf(create_server_cert is None, 'certgen module not available')
+    def test_ssl(self):
+        'Test serving over SSL'
+        with TestServer(lambda data:(data.path[0] + data.read())) as server:
+            address = server.address[0]
+        with TemporaryDirectory('srv-test-ssl') as tdir:
+            cert_file, key_file, ca_file = map(lambda x:os.path.join(tdir, x), 'cka')
+            create_server_cert(address, ca_file, cert_file, key_file, key_size=1024)
+            ctx = ssl.create_default_context(cafile=ca_file)
+            with TestServer(lambda data:(data.path[0] + data.read()), ssl_certfile=cert_file, ssl_keyfile=key_file) as server:
+                conn = httplib.HTTPSConnection(server.address[0], server.address[1], strict=True, context=ctx)
+                conn.request('GET', '/test', 'body')
+                r = conn.getresponse()
+                self.ae(r.status, httplib.OK)
+                self.ae(r.read(), b'testbody')
+                cert = conn.sock.getpeercert()
+                subject = dict(x[0] for x in cert['subject'])
+                self.ae(subject['commonName'], address)

src/calibre/test_build.py

@@ -75,6 +75,10 @@ def test_lxml():
     else:
         raise RuntimeError('lxml failed')
 
+def test_certgen():
+    from calibre.utils.certgen import create_key_pair
+    create_key_pair()
+
 def test_winutil():
     from calibre.devices.scanner import win_pnp_drives
     from calibre.constants import plugins
@@ -223,6 +227,7 @@ def test():
     test_apsw()
     test_imaging()
     test_unrar()
+    test_certgen()
     test_icu()
     test_woff()
     test_qt()

src/calibre/utils/certgen.c

@@ -0,0 +1,353 @@
+/*
+ * certgen.c
+ * Copyright (C) 2015 Kovid Goyal <kovid at kovidgoyal.net>
+ *
+ * Distributed under terms of the GPL3 license.
+ */
+
+#define UNICODE
+#include <Python.h>
+
+#include <openssl/rand.h>
+#ifdef _WIN32
+/* See http://openssl.6102.n7.nabble.com/The-infamous-win32-X509-NAME-define-problem-td11794.html */
+#undef X509_NAME
+#endif
+#include <openssl/x509.h>
+#include <openssl/ssl.h>
+#include <openssl/rsa.h>
+#include <openssl/evp.h>
+#include <openssl/err.h>
+#include <openssl/conf.h>
+
+static PyObject* set_error(const char *where) {
+    char *buf = NULL;
+    unsigned long err = ERR_get_error();
+    if (err == 0) {
+        return PyErr_Format(PyExc_RuntimeError, "Error calling: %s: OpenSSL error queue is empty", where);
+    }
+    buf = ERR_error_string(err, NULL);
+    if (!buf) {
+        PyErr_SetString(PyExc_RuntimeError, "An unknown error occurred (OpenSSL error string returned NULL)");
+        return NULL;
+    }
+    return PyErr_Format(PyExc_ValueError, "Error calling: %s: %s", where, buf);
+}
+
+static void free_rsa_keypair(PyObject *capsule) {
+    RSA *KeyPair = PyCapsule_GetPointer(capsule, NULL);
+    if (KeyPair) RSA_free(KeyPair);
+}
+
+static PyObject* create_rsa_keypair(PyObject *self, PyObject *args) {
+    int keysize = 0;
+    RSA *KeyPair = NULL;
+    BIGNUM *BigNumber = NULL;
+    PyObject *ans = NULL;
+    int ret = 0;
+
+    if(!PyArg_ParseTuple(args, "i", &keysize)) return NULL;
+    if (keysize < 1024) return PyErr_Format(PyExc_ValueError, "The key size %d is less than 1024. 1024 is the minimum.", keysize);
+    if (RAND_status() != 1) return PyErr_Format(PyExc_RuntimeError, "The OopenSSL PRNG failed to seed itself");
+
+    KeyPair = RSA_new();
+    if (!KeyPair) return set_error("RSA_new");
+    BigNumber = BN_new();
+    if (!BigNumber) {set_error("BN_new"); goto error;}
+    if (!BN_set_word(BigNumber, RSA_F4)) { set_error("BN_set_word"); goto error; }
+    Py_BEGIN_ALLOW_THREADS;
+    ret = RSA_generate_key_ex(KeyPair, keysize, BigNumber, NULL);
+    Py_END_ALLOW_THREADS;
+    if (!ret) { set_error("RSA_generate_key_ex"); goto error; }
+
+    ans = PyCapsule_New(KeyPair, NULL, free_rsa_keypair);  
+    if (ans == NULL) { PyErr_NoMemory(); goto error; }
+error:
+    if(BigNumber) BN_free(BigNumber); 
+    if (!ans && KeyPair) RSA_free(KeyPair);
+    return ans;
+}
+
+#ifdef _WIN32
+static int add_entry(X509_NAME *Name, const char *field, const char *bytes) {
+#else
+static inline int add_entry(X509_NAME *Name, const char *field, const char *bytes) {
+#endif
+    if (bytes && *bytes) {
+        if (!X509_NAME_add_entry_by_txt(Name, field, MBSTRING_ASC, (const unsigned char*)bytes, -1, -1, 0)) { set_error("X509_NAME_add_entry_by_txt"); return 0; }
+    }
+    return 1;
+}
+
+static void free_req(PyObject *capsule) {
+    X509_REQ *Cert = PyCapsule_GetPointer(capsule, NULL);
+    if (Cert) X509_REQ_free(Cert);
+}
+
+static PyObject* create_rsa_cert_req(PyObject *self, PyObject *args) {
+    RSA *KeyPair = NULL;
+    PyObject *capsule = NULL, *ans = NULL;
+    X509_NAME *Name = NULL;
+    char *common_name = NULL, *country = NULL, *state = NULL, *locality = NULL, *org = NULL, *org_unit = NULL, *email = NULL;
+    X509_REQ *Cert = NULL;
+    EVP_PKEY *PrivateKey = NULL;
+    int ok = 0, signature_length = 0;
+
+    if(!PyArg_ParseTuple(args, "Oszzzzzz", &capsule, &common_name, &country, &state, &locality, &org, &org_unit, &email)) return NULL;
+    if(!PyCapsule_CheckExact(capsule)) return PyErr_Format(PyExc_TypeError, "The key is not a capsule object");
+    KeyPair = PyCapsule_GetPointer(capsule, NULL);
+    if (!KeyPair) return PyErr_Format(PyExc_TypeError, "The key capsule is NULL");
+    Cert = X509_REQ_new();
+    if (!Cert) return set_error("X509_REQ_new");
+    if (!X509_REQ_set_version(Cert, 1)) { set_error("X509_REQ_set_version"); goto error; }
+    Name = X509_REQ_get_subject_name(Cert);
+    if (!Name) { set_error("X509_REQ_get_subject_name"); goto error; }
+    if (!add_entry(Name, "C", country)) goto error;
+    if (!add_entry(Name, "ST", state)) goto error;
+    if (!add_entry(Name, "L", locality)) goto error;
+    if (!add_entry(Name, "O", org)) goto error;
+    if (!add_entry(Name, "OU", org_unit)) goto error;
+    if (!add_entry(Name, "emailAddress", email)) goto error;
+    if (!add_entry(Name, "CN", common_name)) goto error;
+
+    PrivateKey = EVP_PKEY_new();
+    if (!PrivateKey) { set_error("EVP_PKEY_new"); goto error; }
+    if (!EVP_PKEY_set1_RSA(PrivateKey, KeyPair)) { set_error("EVP_PKEY_set1_RSA"); goto error; }
+    if (!X509_REQ_set_pubkey(Cert, PrivateKey))  { set_error("X509_REQ_set_pubkey"); goto error; }
+    Py_BEGIN_ALLOW_THREADS;
+    signature_length = X509_REQ_sign(Cert, PrivateKey, EVP_sha256());
+    Py_END_ALLOW_THREADS;
+    if (signature_length <= 0) { set_error("X509_REQ_sign"); goto error; }
+    ans = PyCapsule_New(Cert, NULL, free_req);
+    if (!ans) { PyErr_NoMemory(); goto error; }
+    ok = 1;
+error:
+    if (!ok) {
+        if (Cert) X509_REQ_free(Cert);
+    }
+    if (PrivateKey) EVP_PKEY_free(PrivateKey);
+    return ans;
+}
+
+static void free_cert(PyObject *capsule) {
+    X509 *Cert = PyCapsule_GetPointer(capsule, NULL);
+    if (Cert) X509_free(Cert);
+}
+
+/* Presently this just uses a random number, but a more appealling solution
+ * is to switch to using a hash of certain key elements. Apparently Verisign do
+ * something similar and it seems like a damned good idea. The suggested
+ * fields to hash are
+ * - subject
+ * - notBefore
+ * - not After
+ * The reason for this function is to allow easier abstraction :-)
+ */
+static int certificate_set_serial(X509 *cert)
+{
+    BIGNUM *bn = NULL;
+    int rv = 0;
+    ASN1_INTEGER *sno = ASN1_INTEGER_new();
+
+    if (!sno) {
+        PyErr_NoMemory(); return 0;
+    }
+    bn=BN_new();
+    if (!bn) {
+        ASN1_INTEGER_free(sno);
+        PyErr_NoMemory(); return 0;
+    }
+#define SERIAL_RAND_BITS 128
+    if (BN_pseudo_rand(bn, SERIAL_RAND_BITS, 0, 0) == 1 &&
+        (sno = BN_to_ASN1_INTEGER(bn,sno)) != NULL &&
+        X509_set_serialNumber(cert, sno) == 1)
+        rv = 1;
+    else 
+        set_error("X509_set_serialNumber");
+    BN_free(bn);
+    ASN1_INTEGER_free(sno);
+    return rv;
+}
+
+
+static PyObject* create_rsa_cert(PyObject *self, PyObject *args) {
+    PyObject *reqC = NULL, *CA_certC = NULL, *CA_keyC = NULL, *ans = NULL;
+    X509_REQ *req = NULL;
+    X509 *CA_cert = NULL, *Cert = NULL;
+    RSA *CA_key = NULL;
+    X509_NAME *Name = NULL;
+    EVP_PKEY *PubKey = NULL, *PrivateKey = NULL;
+    int not_before = 0, expire = 1, req_is_for_CA_cert = 0, signature_length = 0, ok = 0;
+
+    if(!PyArg_ParseTuple(args, "OOO|ii", &reqC, &CA_certC, &CA_keyC, &not_before, &expire)) return NULL;
+    if(!PyCapsule_CheckExact(reqC)) return PyErr_Format(PyExc_TypeError, "The req is not a capsule object");
+    req_is_for_CA_cert = (CA_certC == Py_None) ? 1 : 0;
+    if (!req_is_for_CA_cert) {if(!PyCapsule_CheckExact(CA_certC)) return PyErr_Format(PyExc_TypeError, "The CA_cert is not a capsule object");}
+    if(!PyCapsule_CheckExact(CA_keyC)) return PyErr_Format(PyExc_TypeError, "The CA_key is not a capsule object");
+    req = PyCapsule_GetPointer(reqC, NULL);
+    if (!reqC) PyErr_Format(PyExc_TypeError, "The req capsule is NULL");
+    if (!req_is_for_CA_cert) {
+        CA_cert = PyCapsule_GetPointer(CA_certC, NULL);
+        if (!CA_cert) PyErr_Format(PyExc_TypeError, "The CA_cert capsule is NULL");
+    }
+    CA_key = PyCapsule_GetPointer(CA_keyC, NULL);
+    if (!CA_key) PyErr_Format(PyExc_TypeError, "The CA_key capsule is NULL");
+
+    Cert = X509_new();
+    if (!Cert) { set_error("X509_new"); goto error; }
+    if (!X509_set_version (Cert, 2)) { set_error("X509_set_version"); goto error; }
+    if (!certificate_set_serial(Cert)) goto error;
+#ifdef X509_time_adj_ex
+    if(!X509_time_adj_ex(X509_get_notBefore(Cert), not_before, 0, NULL)) { set_error("X509_time_adj_ex"); goto error; }
+    if(!X509_time_adj_ex(X509_get_notAfter(Cert), expire, 0, NULL)) { set_error("X509_time_adj_ex"); goto error; }
+#else
+    if(!X509_gmtime_adj(X509_get_notBefore(Cert), not_before * 24 * 60 * 60)) { set_error("X509_gmtime_adj"); goto error; }
+    if(!X509_gmtime_adj(X509_get_notAfter(Cert), expire * 24 * 60 * 60)) { set_error("X509_gmtime_adj"); goto error; }
+#endif
+
+    Name = X509_REQ_get_subject_name(req);
+    if (!Name) { set_error("X509_REQ_get_subject_name(req)"); goto error; }
+    if (!X509_set_subject_name(Cert, Name)) { set_error("X509_set_subject_name"); goto error; }
+
+    if (req_is_for_CA_cert) Name = X509_REQ_get_subject_name((X509_REQ*)req);
+    else Name = X509_get_subject_name(CA_cert);
+    if (!Name) { set_error("X509_REQ_get_subject_name(CA_cert)"); goto error; }
+    if (!X509_set_issuer_name(Cert, Name)) { set_error("X509_set_issuer_name"); goto error; }
+
+    PubKey=X509_REQ_get_pubkey(req);
+    if (!PubKey) { set_error("X509_REQ_get_pubkey"); goto error; }
+    if (!X509_REQ_verify(req, PubKey)) { set_error("X509_REQ_verify"); goto error; }
+    if (!X509_set_pubkey(Cert, PubKey)) { set_error("X509_set_pubkey"); goto error; }
+    PrivateKey = EVP_PKEY_new();
+    if (!PrivateKey) { set_error("EVP_PKEY_new"); goto error; }
+    if (!EVP_PKEY_set1_RSA(PrivateKey, CA_key)) { set_error("EVP_PKEY_set1_RSA"); goto error; }
+    Py_BEGIN_ALLOW_THREADS;
+    signature_length = X509_sign(Cert, PrivateKey, EVP_sha256());
+    Py_END_ALLOW_THREADS;
+    if (signature_length <= 0) { set_error("X509_sign"); goto error; }
+    ans = PyCapsule_New(Cert, NULL, free_cert);
+    if (!ans) { PyErr_NoMemory(); goto error; }
+    ok = 1;
+
+error:
+    if (!ok) { 
+        if (Cert) X509_free(Cert); 
+    }
+    return ans;
+}
+
+static PyObject* serialize_cert(PyObject *self, PyObject *args) {
+    PyObject *capsule = NULL, *ans = NULL;
+    X509 *cert = NULL;
+    BIO *mem = NULL;
+    long sz = 0;
+    char *p = NULL;
+
+    if(!PyArg_ParseTuple(args, "O", &capsule)) return NULL;
+    if(!PyCapsule_CheckExact(capsule)) return PyErr_Format(PyExc_TypeError, "The cert is not a capsule object");
+    cert = PyCapsule_GetPointer(capsule, NULL);
+    if (!cert) return PyErr_Format(PyExc_TypeError, "The cert capsule is NULL");
+
+    mem = BIO_new(BIO_s_mem());
+    if (!mem) return set_error("BIO_new");
+    if (!PEM_write_bio_X509(mem, cert)) { BIO_free(mem); return set_error("PEM_write_bio_X509"); }
+    sz = BIO_get_mem_data(mem, &p);
+    ans = Py_BuildValue("s#", p, sz);
+    BIO_free(mem);
+    return ans;
+}
+
+static PyObject* cert_info(PyObject *self, PyObject *args) {
+    PyObject *capsule = NULL, *ans = NULL;
+    X509 *cert = NULL;
+    BIO *mem = NULL;
+    long sz = 0;
+    char *p = NULL;
+
+    if(!PyArg_ParseTuple(args, "O", &capsule)) return NULL;
+    if(!PyCapsule_CheckExact(capsule)) return PyErr_Format(PyExc_TypeError, "The cert is not a capsule object");
+    cert = PyCapsule_GetPointer(capsule, NULL);
+    if (!cert) return PyErr_Format(PyExc_TypeError, "The cert capsule is NULL");
+
+    mem = BIO_new(BIO_s_mem());
+    if (!mem) return set_error("BIO_new");
+    if (!X509_print_ex(mem, cert, XN_FLAG_COMPAT, X509_FLAG_COMPAT)) { BIO_free(mem); return set_error("X509_print_ex"); }
+    sz = BIO_get_mem_data(mem, &p);
+    ans = Py_BuildValue("s#", p, sz);
+    BIO_free(mem);
+    return ans;
+}
+
+static PyObject* serialize_rsa_key(PyObject *self, PyObject *args) {
+    PyObject *capsule = NULL, *ans = NULL;
+    char *password = NULL;
+    EVP_PKEY *key = NULL;
+    RSA *keypair = NULL;
+    BIO *mem = NULL;
+    long sz = 0;
+    int ok = 0;
+    char *p = NULL;
+
+    if(!PyArg_ParseTuple(args, "Oz", &capsule, &password)) return NULL;
+    if(!PyCapsule_CheckExact(capsule)) return PyErr_Format(PyExc_TypeError, "The key is not a capsule object");
+    keypair = PyCapsule_GetPointer(capsule, NULL);
+    if (!keypair) return PyErr_Format(PyExc_TypeError, "The key capsule is NULL");
+
+    key = EVP_PKEY_new();
+    if (!key) { set_error("EVP_PKEY_new"); goto error; }
+    if (!EVP_PKEY_set1_RSA(key, keypair)) { set_error("EVP_PKEY_set1_RSA"); goto error; }
+
+    mem = BIO_new(BIO_s_mem());
+    if (!mem) {set_error("BIO_new"); goto error; }
+    if (password && *password) ok = PEM_write_bio_PrivateKey(mem, key, EVP_des_ede3_cbc(), NULL, 0, 0, password);
+    else ok = PEM_write_bio_PrivateKey(mem, key, NULL, NULL, 0, 0, NULL);
+    if (!ok) { set_error("PEM_write_bio_PrivateKey"); goto error; }
+    sz = BIO_get_mem_data(mem, &p);
+    ans = Py_BuildValue("s#", p, sz);
+error:
+    if (mem) BIO_free(mem);
+    if (key) EVP_PKEY_free(key);
+    return ans;
+}
+
+static PyMethodDef certgen_methods[] = {
+    {"create_rsa_keypair", create_rsa_keypair, METH_VARARGS,
+        "create_rsa_keypair(size)\n\nCreate a RSA keypair of the specified size"
+    },
+
+    {"create_rsa_cert_req", create_rsa_cert_req, METH_VARARGS,
+        "create_rsa_cert_req(keypair, common_name, country, state, locality, org, org_unit, email_address)\n\nCreate a certificate signing request."
+    },
+
+    {"create_rsa_cert", create_rsa_cert, METH_VARARGS,
+        "create_rsa_cert(req, CA_cert, CA_key, not_before, expire)\n\nCreate a certificate from a signing request."
+    },
+
+    {"serialize_cert", serialize_cert, METH_VARARGS,
+        "serialize_cert(cert)\n\nReturn certificate as a PEM format bytestring"
+    },
+
+    {"serialize_rsa_key", serialize_rsa_key, METH_VARARGS,
+        "serialize_rsa_key(key, [password])\n\nReturn key as a PEM format bytestring, optionally encrypted by password"
+    },
+
+    {"cert_info", cert_info, METH_VARARGS,
+        "cert_info(cert)\n\nReturn the certificate information (certificate in text format)"
+    },
+
+    {NULL, NULL, 0, NULL}
+};
+
+
+PyMODINIT_FUNC
+initcertgen(void) {
+    PyObject *m;
+    m = Py_InitModule3("certgen", certgen_methods,
+    "OpenSSL bindings to easily create certificates/certificate authorities"
+    );
+    if (m == NULL) return;
+    OpenSSL_add_all_algorithms();
+    ERR_load_crypto_strings();
+    ERR_load_BIO_strings();
+}
+

src/calibre/utils/certgen.py

@@ -0,0 +1,73 @@
+#!/usr/bin/env python2
+# vim:fileencoding=utf-8
+from __future__ import (unicode_literals, division, absolute_import,
+                        print_function)
+
+__license__ = 'GPL v3'
+__copyright__ = '2015, Kovid Goyal <kovid at kovidgoyal.net>'
+
+from calibre.constants import plugins
+certgen, err = plugins['certgen']
+if err:
+    raise ImportError('Failed to load teh certgen module with error: %s' % err)
+
+def create_key_pair(size=2048):
+    return certgen.create_rsa_keypair(size)
+
+def create_cert_request(
+    key_pair, common_name,
+    country='IN', state='Maharashtra', locality='Mumbai', organization=None,
+    organizational_unit=None, email_address=None
+):
+    def enc(x):
+        if isinstance(x, type('')):
+            x = x.encode('ascii')
+        return x or None
+    return certgen.create_rsa_cert_req(
+        key_pair, *map(enc, (
+            common_name, country, state, locality, organization, organizational_unit, email_address))
+    )
+
+def create_cert(req, ca_cert, ca_keypair, expire=365, not_before=0):
+    return certgen.create_rsa_cert(req, ca_cert, ca_keypair, not_before, expire)
+
+def create_ca_cert(req, ca_keypair, expire=365, not_before=0):
+    return certgen.create_rsa_cert(req, None, ca_keypair, not_before, expire)
+
+def serialize_cert(cert):
+    return certgen.serialize_cert(cert)
+
+def serialize_key(key_pair, password=None):
+    return certgen.serialize_rsa_key(key_pair, password)
+
+def cert_info(cert):
+    return certgen.cert_info(cert).decode('utf-8')
+
+def create_server_cert(
+    domain, ca_cert_file=None, server_cert_file=None, server_key_file=None,
+    expire=365, ca_key_file=None, ca_name='Dummy Certificate Authority', key_size=2048,
+    country='IN', state='Maharashtra', locality='Mumbai', organization=None,
+    organizational_unit=None, email_address=None, encrypt_key_with_password=None,
+):
+    # Create the Certificate Authority
+    cakey = create_key_pair(key_size)
+    careq = create_cert_request(cakey, ca_name)
+    cacert = create_ca_cert(careq, cakey)
+
+    # Create the server certificate issued by the newly created CA
+    pkey = create_key_pair(key_size)
+    req = create_cert_request(pkey, domain, country, state, locality, organization, organizational_unit, email_address)
+    cert = create_cert(req, cacert, cakey, expire=expire)
+
+    def export(dest, obj, func, *args):
+        if dest is not None:
+            data = func(obj, *args)
+            if hasattr(dest, 'write'):
+                dest.write(data)
+            else:
+                with open(dest, 'wb') as f:
+                    f.write(data)
+    export(ca_cert_file, cacert, serialize_cert)
+    export(server_cert_file, cert, serialize_cert)
+    export(server_key_file, pkey, serialize_key, encrypt_key_with_password)
+    export(ca_key_file, cakey, serialize_key, encrypt_key_with_password)