M2Crypto和M2Crypto的安装

参考网址： http://stackoverflow.com/questions/3107036/how-do-i-install-m2crypto-on-ubuntu

http://www.newsmth.net/nForum/#!article/Python/60734

1、安装依赖项

- **Python 2.3 or newer**

- **OpenSSL 0.9.7 or newer**

sudo apt-get install openssl

- **SWIG 1.3.28 or newer**

sudo apt-get install swig

2、安装 M2Crypto

sudo apt-get install python-m2crypto

3、添加库

windows-preference中的

 加入包 /usr/lib/python2.7/dist-packages/M2Crypto  4、实例

（1）公私钥（rsa）

import BIO, RSA, EVP, util

class rsa:

    def genRsaKeypair(self,rsalen = 1024):

        rsa_key = RSA.gen_key(rsalen, 3, lambda *arg:None) 

        rsa_key.save_key("pri_key.pem", None)

        rsa_key.save_pub_key("pub_key.pem")

    def encryptionByPubkey(self,message):

        pub_key = RSA.load_pub_key("pub_key.pem")

        return pub_key.public_encrypt(message, RSA.pkcs1_padding)

    def decryptionByPrikey(self,message):

        string = open("pri_key.pem","rb").read();

        bio = BIO.MemoryBuffer(string);

        pri_key = RSA.load_key_bio(bio);

        return pri_key.private_decrypt(message,RSA.pkcs1_padding)

    def signByPrikeyAndSha1(self,message):

        m=EVP.MessageDigest("sha1") 

        m.update(message) 

        digest=m.final() 

        key_str=file("pri_key.pem","rb").read() 

        key=RSA.load_key_string(key_str, util.no_passphrase_callback) 

        return key.sign(digest, "sha1") 

    def verifyByPubkeyAndSha1(self,sign,message):

        m=EVP.MessageDigest("sha1") 

        m.update(message) 

        digest=m.final() 

        cert_str=file("pub_key.pem", "rb").read() 

        mb=BIO.MemoryBuffer(cert_str) 

        cert=RSA.load_pub_key_bio(mb)

        try:

            cert.verify(digest, sign, "sha1")

            return True

        except:

            return False

#if __name__ == "main":       

r = rsa()

r.genRsaKeypair()

print r.decryptionByPrikey(r.encryptionByPubkey("message"))

print r.verifyByPubkeyAndSha1(r.signByPrikeyAndSha1("message"), "mesage")

（2）对称密钥（3DES）

种子sed需要与密码的长度相同

import EVP from StringIO import StringIO class TripleDES: def __init__(self,salt,level): self._salt = salt self._level = level #the length of sed is equals to the length of password #the sed,salt,password is must same when en/decrption def encryptBySha1(self,message,sed,password): out=StringIO() m=EVP.Cipher("des_ede3_cbc", password, sed, 1, 1, "sha1", self._salt, self._level, 1) out.write(m.update(message)) out.write(m.final()) return out.getvalue() def decryptBySha1(self,message,sed,password): out=StringIO() m=EVP.Cipher("des_ede3_cbc", password, sed, 0, 1, "sha1", self._salt, self._level, 1) out.write(m.update(message)) try: out.write(m.final()) except: return None return out.getvalue() t = TripleDES("salt",5) print t.decryptBySha1(t.encryptBySha1("message", "123456","passwd"),"123456" ,"passd")

（3）哈希算法

hash生产消息摘要

import EVP class HashBysha1Ormd5: def __init__(self,alg): self._alg = alg def hash(self,message): m=EVP.MessageDigest(self._alg) m.update(message) return m.digest() h = HashBysha1Ormd5("sha1") print h.hash("message")