Version 1.10.4, 2013-01-07
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* Avoid a conditional operation in the power mod implementations on if
  a nibble of the exponent was zero or not. This may help protect
  against certain forms of side channel attacks.

* The SRP6 code was checking for invalid values as specified in RFC
  5054, specifically values equal to zero mod p. However SRP would
  accept negative A/B values, or ones larger than p, neither of which
  should occur in a normal run of the protocol. These values are now
  rejected. Credits to Timothy Prepscius for pointing out these values
  are not normally used and probably signal something fishy.

* The return value of version_string is now a compile time constant
  string, so version information can be more easily extracted from
  binaries.
