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