1 .\" $OpenBSD: moduli.5,v 1.3 2001/06/24 18:50:52 provos Exp $
3 .\" Copyright 1997, 2000 William Allen Simpson <wsimpson@greendragon.com>
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38 .Nd system moduli file
42 file contains the system-wide Diffie-Hellman prime moduli for the
48 Each line in this file contains the following fields:
49 .Va Time , Type , Tests , Tries , Size , Generator ,
52 The fields are separated by white space (tab or blank).
53 .Bl -tag -width indent
54 .It Va Time Pq Vt yyyymmddhhmmss
55 Specifies the system time that the line was appended to the file.
56 The value 00000000000000 means unknown (historic).
57 .\"The file is sorted in ascending order.
58 .It Va Type Pq Vt decimal
59 Specifies the internal structure of the prime modulus.
61 .Bl -tag -width indent -compact
64 often learned from peer during protocol operation,
65 and saved for later analysis.
68 a common large number.
71 meets basic structural requirements.
75 Sophie-Germaine (q = (p-1)/2);
76 usually generated in the process of testing safe or strong primes.
79 useful for RSA public key generation.
82 .Va Tests Pq Vt decimal
85 Specifies the methods used in checking for primality.
86 Usually, more than one test is used.
88 .Bl -tag -width indent -compact
91 often learned from peer during protocol operation,
92 and saved for later analysis.
95 failed one or more tests.
96 In this case, the highest bit specifies the test that failed.
99 checked for division by a range of smaller primes.
107 .It Va Tries Pq Vt decimal
108 Depends on the value of the highest valid Test bit,
109 where the method specified is:
111 .Bl -tag -width indent -compact
120 number of primes sieved.
121 Commonly on the order of 32,000,000.
124 number of M-R iterations.
125 Commonly on the order of 32 to 64.
135 .It Va Size Pq Vt decimal
136 Specifies the number of significant bits.
137 .It Va Generator Pq Vt "hex string"
138 Specifies the best generator for a Diffie-Hellman exchange.
139 0 = unknown or variable,
141 .It Va Modulus Pq Vt "hex string"
145 The file is searched for moduli that meet the appropriate
150 When more than one meet the criteria,
151 the selection should be weighted toward newer moduli,
152 without completely disqualifying older moduli.
154 .Bl -tag -width ".Pa /etc/ssh/moduli" -compact
155 .It Pa /etc/ssh/moduli