1. Salt
@h13i32maru

2. Web
id uid password
1 alice e2fc714c4727ee9395f324cd2e7f331f
2 bob 81dc9bdb52d04dc20036dbd8313ed055
3 carol 098f6bcd4621d373cade4e832627b4f6

4. ( )
1234 81dc9bdb52d04dc20036dbd8313ed055
abcd e2fc714c4727ee9395f324cd2e7f331f
qwer 962012d09b8170d912f0669f6d7d9d07
pass 1a1dc91c907325c69271ddf0c944bc72
... ...
※

5. [0-9A-Za-z-_]
MD5
4 640MB 1600
5 50GB 10
6 2.6TB 680
7 167TB 4.4
8 12PB 280

6. (´ ω )

9. • Px H() Cx R()
• C P
1. P1 H() C1
2. C1 R() P2
3. P2 H() C2
4. C2 R() P3
5. m [ P1→H()→C1→R()→P2→H()→C2→R() ... Cm-1→R()→Pm ]
6. P1 Pm P1→Pm
7. t
m:
P1.1 P1.m t :
P2.1 P2.m ※m t
... ...
Pt.1 Pt.m

10. Cx
1. Cx → R() → P1
2. P1
3.
1. Cx
2. ( )
3.
4. Cx → R() → P1 → H() → C1 → R() → P2
5. P2
6.
1. Cx
2. ( )
3.
7. m
8. m Cx

11. ( ω ´)

12. C++ / Openssl
4
[0-9A-Za-z-_]
MD5
3000
http://h13i32maru.jp/misc/rt/rt.tar.gz

13. 100
10000 75% 100KB
20000 82% 200KB
30000 91% 300KB
40000 96% 400KB
(640MB)
1600 1

14. • MacBookPro 10.6.6 / Core2Duo 2.4GHz / 4GB
• 40000
/
150
( ) 40
( ) 180

15. (´ ω )

16. Salt
$hash = Sha1( $password . $salt );

17. Salt
•
•
id uid password
1 alice 1fadcf6eb4345975be993f237c51d426
2 bob 81dc9bdb52d04dc20036dbd8313ed055
3 carol 1fadcf6eb4345975be993f237c51d426
4 evil 1fadcf6eb4345975be993f237c51d426

18. Salt
•
Salt
id uid Salt
• Salt
id uid password
1 alice fb592cb4152e2aacaaf452714d283f7e
2 bob 27d5c234335b9762416808e2ace80842
3 carol 4ea88541aecef81df60f1d79a0280053
4 evil eaab7a6ec5c9a138022f8c611c0092f5

19. Salt
(´ ω )

20. Salt
uid
Salt

21. •
•
• Salt

22. •
• - Wikipedia
• md5
• salt
• password (salt )