PKI 2 加密算法

                                                                                           yama 20060316
瀵圭О瀵嗙爜绠楁硶/鍗曢挜瀵嗙爜绠楁硶
Symmetric cryptography
鍏遍�氶嵉鏆楀彿鏂瑰紡
   
1銆傜敤鍚屾牱鐨勯挜鏉ュ姞瀵嗗拰瑙ｅ瘑銆備娇鐢ㄧ殑閽ュ彨鍋歋ymmetric Key銆?br>
2銆傚姞瀵嗘柟娉曞ぇ浣撳垎2绉嶃�?br>    Block(銉栥儹銉冦偗)锛氭姤鏂囨寜鐓т竴瀹氱殑闀垮害鍒嗗壊锛屽垎鍒�杩涜�屽姞瀵?br>    Stream(銈广儓銉�銉笺�?锛氫笉鍒嗗壊鎶ユ枃锛岄�愭�★�?-鍑燽it姣忥級鍔犲瘑

3銆傚叿浣撴妧鏈�锛�
                      KeyLen             Description
    DES            56bit    Block    Data Encryption Standard
    Triple-DES   168bit   Block    3娆�DES鍔犲瘑銆?鍥炰笉鍚岄挜鐨勬儏鍐?Key鏂瑰紡锛?鍜?鍥炲悓鏍烽挜鐨?Key鏂瑰紡
    IDEA            128bit   Block   International Data Encryption Algorithm(64bits block)
    RC2            8-1024   Block   RFC2268
    RC4            40-256   Stream
    RC5            -2048     Block
    CAST-128    -128       Block    RFC2144
    AES            128,192,156   Block   Advanced Encryption Standard

4銆侰BC (Cipher Block Chaining)
    瀵逛簬Block鏂瑰紡鏉ヨ�达紝鐢变簬鏀诲嚮鑰呭彲浠ュ�逛簬鍏抽敭浣嶇疆鏉ユ敾鍑绘墍浠ュ瓨鍦ㄥ嵄闄╂�с�?br>    涓轰簡闄嶄綆杩欑�嶅嵄闄╋紝鎴戜滑閫氳繃澧炲姞Block闂寸殑鍏宠仈鎬ф潵瑙ｅ喅銆?br>   
    ECB   鍒嗗壊鐨凚log鍒嗗埆鍔犲瘑锛孊log涔嬮棿娌℃湁鍏宠仈->鍗遍櫓
    CBC   鍔犲瘑瀹屼簡鐨凚log鍜屾帴鐫�鐨勪竴涓�杩涜�孹OR澶勭悊锛屽�硅繖涓�鍊兼潵鍔犲瘑澶勭悊銆備篃灏辨槸璇村悇涓狟log鏄�杩為�?br>    CFB   鍔犲瘑瀹屼簡鐨凚log鍜屾帴鐫�鐨勪竴涓�杩涜�孹OR澶勭悊锛屾妸璇ュ�糉eedback
    OFB   闅忔満鏁扮敓鎴愪笌Blog杩涜�孹OR杩愮畻銆傚墠涓�涓狟log鐨勯殢鏈烘暟鍔犲瘑鍚庢垚涓哄悗涓�涓�鐨勯殢鏈烘暟銆?br>
   
闈炲�圭О瀵嗙爜绠楁�?鍙岄挜瀵嗙爜绠楁硶/鍏�閽ュ瘑鐮佺畻娉�
Asymmetric Cryptography/Public Key Cryptography
闈炲�剧О鏆楀彿鏂瑰�?/鍏�闁嬮嵉鏆楀彿鏂瑰�?br>
1銆傚姞瀵?br>鍔犲瘑鎶ユ枃鏂规硶
example:
A->B
    1.B create public key and private key.
    2.B announce public key by internet
    3.A want to send message to B, so get the public key from internet
    4.A send the message which encrypted by public key to  B
    5.B get the normal message by private key
Total (A---message encrypted by public key --- internet --- cracked by private key ---B)

A->E, F, D
    1.E, F, D create respective public key
    2.A create Symmetric Key
    3.A encrypt message with Symmetric Key.
    4.A encrypt symmetric key by respective public key
    5.A send message and encrypted key message to every one
    6.E crack key message by E private key and get symmetric key. Then crack message by the symmetric key
       F, D also

2銆傛暟瀛楃�惧悕锛圖igital Signature锛?br>    浜庡姞瀵嗙浉鍙嶏紝鏁板瓧绛惧悕鍒╃敤鐨勬槸private key鍔犲瘑瑕侀�佸嚭鐨勪笢瑗匡紝鐢╬ublic key瑙ｅ瘑灏卞彲浠ョ煡閬撳彂閫佷汉鐨勮韩浠斤紝杈惧埌涓�浜鸿�よ瘉鍜屽畬鍏ㄦ�т繚璇併�?br>
3銆備富瑕佹妧鏈?br>    DH (Diffie-Hellman) 閽ヤ氦鎹?Symmetric Key瀹夊叏浜ゆ崲绠楁硶
    RSA (Rivest-Shamir-Adleman) 鍔犲瘑/绛惧悕/閽ヤ氦鎹?鍒╃敤澶ф暣鏁扮殑绱犲洜鏁板垎瑙ｉ棶棰?br>    DSA (Digital Signature Algorithm) 绛惧悕 鍒╃敤绂绘暎瀵规暟闂�棰橈紝鍙�鏈夌�惧悕鍔熻兘锛屼笉鑳界敤浜庡姞瀵�
    ECC (Elliptic Curve cryptosystem) 鍔犲瘑/绛惧悕/閽ヤ氦鎹?绂绘暎瀵规暟闂�棰橀噷闈㈠啀鍔犱笂妞�鍦嗘洸绾块棶棰?br>    浠ヤ笂閮芥槸澶ф�傜殑鎻忚堪锛屾湁鍏磋叮鐨勪汉鍙�浠ヨ嚜宸卞幓google鐙椾竴涓嬬湅鐪嬮兘鏄�鎬庝箞鏍风殑绠楁硶銆?br>   


                                                                                                                            yama 20060316