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-rw-r--r--WARNING.RNG13
1 files changed, 6 insertions, 7 deletions
diff --git a/WARNING.RNG b/WARNING.RNG
index 5f129f402..21f4901c9 100644
--- a/WARNING.RNG
+++ b/WARNING.RNG
@@ -12,16 +12,14 @@ A particularly pernicious problem arises with DSA keys (used by the
12ssh2 protocol). Performing a DSA signature (which is required for 12ssh2 protocol). Performing a DSA signature (which is required for
13authentication), entails the use of a 160 bit random number. If an 13authentication), entails the use of a 160 bit random number. If an
14attacker can predict this number, then they can deduce your *private* 14attacker can predict this number, then they can deduce your *private*
15key and impersonate you. 15key and impersonate you or your hosts.
16 16
17If you are using the builtin random number support (configure will 17If you are using the builtin random number support (configure will
18tell you if this is the case), then read this document in its entirety 18tell you if this is the case), then read this document in its entirety.
19and consider disabling ssh2 support (by adding "Protocol 1" to
20sshd_config and ssh_config).
21 19
22Please also request that your OS vendor provides a kernel-based random 20Please also request that your OS vendor provides a kernel-based random
23number collector (/dev/random) in future versions of your operating 21number collector (/dev/random) in future versions of your operating
24systems. 22systems by default.
25 23
26On to the description... 24On to the description...
27 25
@@ -40,9 +38,10 @@ the specified program.
40 38
41The random number code will also read and save a seed file to 39The random number code will also read and save a seed file to
42~/.ssh/prng_seed. This contents of this file are added to the random 40~/.ssh/prng_seed. This contents of this file are added to the random
43number generator at startup. 41number generator at startup. The goal here is to maintain as much
42randomness between sessions as possible.
44 43
45This approach presents two problems: 44The entropy collection code has two main problems:
46 45
471. It is slow. 461. It is slow.
48 47