单向散列函数.pptVIP

3.3.2 举例 我们以求字符串abc的SHA–1散列值为例来说明上面描述的过程。abc的二进制表示01100010 (1) 填充消息：消息长l=24，先填充1位1，然后填充423位0，再用消息长24，即000000018填充。 (2) 初始化： H0 = 0H1 = 0xEFCDAB89 H2 = 0x98BADCFE H3 = 0H4 = 0xC3D2E1F0 (3) 主循环：处理消息字块1(本例中只有1个字块)，分成16个字： W[0] W[1] W[2] W[3] W[4] W[5] W[6] W[7] W[8] W[9] W[10] W[11] W[12] W[13] W[14] W[15] 然后根据3.2.1节中描述的过程计算，其中，循环“for t = 0 to 79”中，各步A、B、C、D、E?的值如下： A B C D E t = 0: 0116FC33 7BF36AE2 98BADCFE t = 1: 8990536D 0116FC33 59D148C0 7BF36AE2 98BADCFE t = 2: A1390F08 8990536D C045BF0C 59D148C0 7BF36AE2 t = 3: CDD8E11B A1390F08 626414DB C045BF0C 59D148C0 t = 4: CFD499DE CDD8E11B 284E43C2 626414DB C045BF0C t = 5: 3FC7CA40 CFD499DE F3763846 284E43C2 626414DB t = 6: 993E30C1 3FC7CA40 B3F52677 F3763846 284E43C2 t = 7: 9E8C07D4 993E30C1 0FF1F290 B3F52677 F3763846 t = 8: 4B6AE328 9E8C07D4 664F8C30 0FF1F290 B3F52677 t = 9: 8351F929 4B6AE328 27A301F5 664F8C30 0FF1F290 t = 10: FBDA9E89 8351F929 12DAB8CA 27A301F5 664F8C30 t = 11: 63188FE4 FBDA9E89 60D47E4A 12DAB8CA 27A301F5 t = 12: 4607B664 63188FE4 7EF6A7A2 60D47E4A 12DAB8CA t = 13: 9128F695 4607B664 18C623F9 7EF6A7A2 60D47E4A t = 14: 196BEE77 9128F695 1181ED99 18C623F9 7EF6A7A2 t = 15: 20BDD62F 196BEE77 644A3DA5 1181ED99 18C623F9 t = 16: 4E925823 20BDD62F C65AFB9D 644A3DA5 1181ED99 t = 17: 82AA6728 4E925823 C82F758B C65AFB9D 644A3DA5 t = 18: DC64901D 82AA6728 D3A49608 C82F758B C65AFB9D t = 19: FD9E1D7D DC64901D 20AA99CA D3A49608 C82F758B t = 20: 1A37B0CA FD9E1D7D 20AA99CA D3A49608 t = 21: 33A23BFC 1A37B0CA 7F67875F 7719