#encoding: utf8
import os
import M2Crypto
#随机数生成器(1024位随机）
M2Crypto.Rand.rand_seed(os.urandom(1024))
#生成一个1024位公钥与私密钥证书
Geekso = M2Crypto.RSA.gen_key(1024, 65537)
Geekso.save_key('Geekso.com-private.pem', None)
Geekso.save_pub_key('Geekso.com-public.pem')

#使用公钥证书加密开始
WriteRSA = M2Crypto.RSA.load_pub_key('Geekso.com-public.pem')
CipherText = WriteRSA.public_encrypt("这是一个秘密消息,只能用私钥进行解密",M2Crypto.RSA.pkcs1_oaep_padding)
print "加密的串是:"
print CipherText.encode('base64')

#对加密串进行签名
MsgDigest = M2Crypto.EVP.MessageDigest('sha1')
MsgDigest.update(CipherText)
#提示，这里也可以使用私钥签名
#WriteRSA = M2Crypto.RSA.load_key ('Geekso.com-private.pem')
#Signature = WriteRSA.sign_rsassa_pss(MsgDigest.digest())
Signature = Geekso.sign_rsassa_pss(MsgDigest.digest())
print "签名的串是:"
print Signature.encode('base64')

#使用私钥证书解密开始
ReadRSA = M2Crypto.RSA.load_key ('Geekso.com-private.pem')
try:
    PlainText = ReadRSA.private_decrypt (CipherText, M2Crypto.RSA.pkcs1_oaep_padding)
except:
    print "解密错误"
    PlainText = ""

if PlainText :
   print "解密出来的串是："
   print PlainText
   # 验证加密串的签名
   MsgDigest = M2Crypto.EVP.MessageDigest('sha1')
   MsgDigest.update(CipherText)
   #提示，如果是用私钥签名的那就用公钥验证
   #VerifyRSA = M2Crypto.RSA.load_pub_key('Alice-public.pem')
   #VerifyRSA.verify_rsassa_pss(MsgDigest.digest(), Signature)
   if Geekso.verify_rsassa_pss(MsgDigest.digest(), Signature) == 1:
       print "签名正确"
   else:
       print "签名不正确"

#用私钥签名
SignEVP = M2Crypto.EVP.load_key('Geekso.com-private.pem')
SignEVP.sign_init()
SignEVP.sign_update('来自这一客(http://www.geekso.com)的签名串')
StringSignature = SignEVP.sign_final()
print "签名串是:"
print StringSignature.encode('base64')

#用公钥验证签名
PubKey = M2Crypto.RSA.load_pub_key('Geekso.com-public.pem')
VerifyEVP = M2Crypto.EVP.PKey()
VerifyEVP.assign_rsa(PubKey)
VerifyEVP.verify_init()
VerifyEVP.verify_update('来自这一客(http://www.geekso.com)的签名串')
if VerifyEVP.verify_final(StringSignature) == 1:
    print "字符串被成功验证。"
else:
    print "字符串验证失败!"

import time
from M2Crypto import X509, EVP, RSA, ASN1
def issuer_name():
    """
    证书发行人名称(专有名称)。
    Parameters:
        none
    Return:
        X509标准的发行人obj.
    """
    issuer = X509.X509_Name()
    issuer.C = "CN"                # 国家名称
    issuer.CN = "*.geekso.com"       # 普通名字
    issuer.ST = "Hunan Changsha"
    issuer.L = "Hunan Changsha"
    issuer.O = "Geekso Company Ltd"
    issuer.OU = "Geekso Company Ltd"
    issuer.Email = "1085015507@qq.com"
    return issuer

def make_request(bits, cn):
    """
    创建一个X509标准的请求。
    Parameters:
        bits = 证书位数
        cn = 证书名称
    Return:
        返回 X509 request 与 private key (EVP).
    """
    rsa = RSA.gen_key(bits, 65537, None)
    pk = EVP.PKey()
    pk.assign_rsa(rsa)
    req = X509.Request()
    req.set_pubkey(pk)
    name = req.get_subject()
    name.C = "US"
    name.CN = cn
    req.sign(pk,'sha256')
    return req, pk

def make_certificate_valid_time(cert, days):
    """
    从当前时间算起证书有效期几天。
    Parameters:
        cert = 证书obj
        days = 证书过期的天数
    Return:
        none
    """
    t = long(time.time()) # 获取当前时间
    time_now = ASN1.ASN1_UTCTIME()
    time_now.set_time(t)
    time_exp = ASN1.ASN1_UTCTIME()
    time_exp.set_time(t + days * 24 * 60 * 60)
    cert.set_not_before(time_now)
    cert.set_not_after(time_exp)

def make_certificate(bits):
    """
    创建证书
    Parameters:
        bits = 证快的位数
    Return:
        证书, 私钥 key (EVP) 与 公钥 key (EVP).
    """
    req, pk = make_request(bits, "localhost")
    puk = req.get_pubkey()
    cert = X509.X509()
    cert.set_serial_number(1) # 证书的序例号
    cert.set_version(1) # 证书的版本
    cert.set_issuer(issuer_name()) # 发行人信息
    cert.set_subject(issuer_name()) # 主题信息
    cert.set_pubkey(puk)
    make_certificate_valid_time(cert, 365) # 证书的过期时间
    cert.sign(pk, 'sha256')
    return cert, pk, puk
# 开始创建
cert, pk, puk= make_certificate(1024)
cert.save_pem('geekso.com-cret.pem')
pk.save_key('geekso.com-private.pem',cipher = None, callback = lambda: None)
puk.get_rsa().save_pub_key('geekso.com-public.pem')

def geekso_encrypt_with_certificate(message, cert_loc):
    """
    cert证书加密，可以用私钥文件解密.
    Parameters:
        message = 要加密的串
        cert_loc = cert证书路径
    Return:
        加密串 or 异常串
    """
    cert = X509.load_cert(cert_loc)
    puk = cert.get_pubkey().get_rsa() # get RSA for encryption
    message = base64.b64encode(message)
    try:
        encrypted = puk.public_encrypt(message, RSA.pkcs1_padding)
    except RSA.RSAError as e:
        return "ERROR encrypting " + e.message
    return encrypted

encrypted = geekso_encrypt_with_certificate('www.geekso.com','geekso.com-cret.pem')
print '加密串',encrypted

def geekso_decrypt_with_private_key(message, pk_loc):
    """
    私钥解密证书生成的加密串
    Parameters:
        message = 加密的串
        pk_loc = 私钥路径
    Return:
        解密串 or 异常串
    """
    pk = RSA.load_key(pk_loc) # load RSA for decryption
    try:
        decrypted = pk.private_decrypt(message, RSA.pkcs1_padding)
        decrypted = base64.b64decode(decrypted)
    except RSA.RSAError as e:
        return "ERROR decrypting " + e.message
    return decrypted

print '解密串',geekso_decrypt_with_private_key(encrypted, 'geekso.com-private.pem')

def geekso_encrypt_with_private_key(message,pk_loc):
    """
    私钥加密
    Parameters:
        message = 加密的串
        pk_loc = 私钥路径
    Return:
        加密串 or 异常串
    """
    ReadRSA = RSA.load_key(pk_loc);
    message = base64.b64encode(message)
    try:
        encrypted = ReadRSA.private_encrypt(message,RSA.pkcs1_padding)
    except RSA.RSAError as e:
        return "ERROR encrypting " + e.message
    return encrypted

encrypted = geekso_encrypt_with_private_key('www.geekso.com', 'geekso.com-private.pem')
print encrypted

def geekso_decrypt_with_certificate(message, cert_loc):
    """
    cert证书解密.
    Parameters:
        message = 要解密的串
        cert_loc = cert证书路径
    Return:
        解密后的串 or 异常串
    """
    cert = X509.load_cert(cert_loc)
    puk = cert.get_pubkey().get_rsa()
    try:
        decrypting = puk.public_decrypt(message, RSA.pkcs1_padding)
        decrypting = base64.b64decode(decrypting)
    except RSA.RSAError as e:
        return "ERROR decrypting " + e.message
    return decrypting

decrypting = geekso_decrypt_with_certificate(encrypted, 'geekso.com-cret.pem')
print decrypting

def geekso_sign_with_private_key(message, pk_loc, base64 = True):
    """
    私钥签名
    Parameters:
        message = 待签名的串
        pk_loc = 私钥路径
        base64 = True(bease64处理) False(16进制处理)
    Return:
        签名后的串 or 异常串
    """
    pk = EVP.load_key(pk_loc)
    pk.sign_init()
    try:
        pk.sign_update(message)
        signature = pk.sign_final()
    except EVP.EVPError as e:
        return "ERROR signature " + e.message
    return signature.encode('base64') if base64 is True else signature.encode('hex')

signature = geekso_sign_with_private_key('www.geekso.com','geekso.com-private.pem')
print signature

def geekso_verifysign_with_certificate(message, signature, cert_loc, base64 = True):
    """
    证书验证签名
    Parameters:
        message = 原来签名的串
        signature = 签名后的串
        cert_loc = 证书路径文件
        base64 = True(bease64处理) False(16进制处理)
    Return:
        成功or失败串 or 异常串
    """
    signature = signature.decode('base64') if base64 is True else signature.decode('hex')
    cert = X509.load_cert(cert_loc)
    puk = cert.get_pubkey().get_rsa()
    try:
        verifyEVP = EVP.PKey()
        verifyEVP.assign_rsa(puk)
        verifyEVP.verify_init()
        verifyEVP.verify_update(message)
        verifysign = verifyEVP.verify_final(signature)
        if verifysign == 1 :
            return '成功'
        else :
            return '失败'
    except EVP.EVPError as e:
        return "ERROR Verify Sign " + e.message
    
print geekso_verifysign_with_certificate('www.geekso.com', signature, 'geekso.com-cret.pem')