Python中实现的RC4算法
闲暇之时，用Python实现了一下RC4算法
编码UTF-8
class方式
#/usr/bin/python #coding=utf-8 importsys,os,hashlib,time,base64 classrc4: def__init__(self,public_key=None,ckey_lenth=16): self.ckey_lenth=ckey_lenth self.public_key=public_keyor'none_public_key' key=hashlib.md5(self.public_key).hexdigest() self.keya=hashlib.md5(key[0:16]).hexdigest() self.keyb=hashlib.md5(key[16:32]).hexdigest() self.keyc='' defencode(self,string): self.keyc=hashlib.md5(str(time.time())).hexdigest()[32-self.ckey_lenth:32] string='0000000000'+hashlib.md5(string+self.keyb).hexdigest()[0:16]+string self.result='' self.docrypt(string) returnself.keyc+base64.b64encode(self.result) defdecode(self,string): self.keyc=string[0:self.ckey_lenth] string=base64.b64decode(string[self.ckey_lenth:]) self.result='' self.docrypt(string) result=self.result if(result[0:10]=='0000000000'orint(result[0:10])-int(time.time())>0)andresult[10:26]==hashlib.md5(result[26:]+self.keyb).hexdigest()[0:16]: returnresult[26:] else: returnNone defdocrypt(self,string): string_lenth=len(string) result='' box=list(range(256)) randkey=[] cryptkey=self.keya+hashlib.md5(self.keya+self.keyc).hexdigest() key_lenth=len(cryptkey) foriinxrange(255): randkey.append(ord(cryptkey[i%key_lenth])) foriinxrange(255): j=0 j=(j+box[i]+randkey[i])%256 tmp=box[i] box[i]=box[j] box[j]=tmp foriinxrange(string_lenth): a=j=0 a=(a+1)%256 j=(j+box[a])%256 tmp=box[a] box[a]=box[j] box[j]=tmp self.result+=chr(ord(string[i])^(box[(box[a]+box[j])%256]))
测试：
rc=rc4('nishidahuaidan')
string='我在这里呢，你在那里呢'
print(string)
str=rc.encode(string)
print(str)
str=rc.decode(str)
print(str)
function方式
#/usr/bin/python #coding=utf-8 importsys,os,hashlib,time,base64 defrc4(string,op='encode',public_key='ddd',expirytime=0): ckey_lenth=4 public_key=public_keyandpublic_keyor'' key=hashlib.md5(public_key).hexdigest() keya=hashlib.md5(key[0:16]).hexdigest() keyb=hashlib.md5(key[16:32]).hexdigest() keyc=ckey_lenthand(op=='decode'andstring[0:ckey_lenth]orhashlib.md5(str(time.time())).hexdigest()[32-ckey_lenth:32])or'' cryptkey=keya+hashlib.md5(keya+keyc).hexdigest() key_lenth=len(cryptkey) string=op=='decode'andbase64.b64decode(string[4:])or'0000000000'+hashlib.md5(string+keyb).hexdigest()[0:16]+string string_lenth=len(string) result='' box=list(range(256)) randkey=[] foriinxrange(255): randkey.append(ord(cryptkey[i%key_lenth])) foriinxrange(255): j=0 j=(j+box[i]+randkey[i])%256 tmp=box[i] box[i]=box[j] box[j]=tmp foriinxrange(string_lenth): a=j=0 a=(a+1)%256 j=(j+box[a])%256 tmp=box[a] box[a]=box[j] box[j]=tmp result+=chr(ord(string[i])^(box[(box[a]+box[j])%256])) ifop=='decode': if(result[0:10]=='0000000000'orint(result[0:10])-int(time.time())>0)andresult[10:26]==hashlib.md5(result[26:]+keyb).hexdigest()[0:16]: returnresult[26:] else: returnNone else: returnkeyc+base64.b64encode(result)
测试：
string='我在这里呢，你在那里呢' print(string) str=rc4(string,'encode') print(str) rc=rc4(str,'decode') print(rc)