Move password hashing schemes to src/passhash

Set the upper limit on bcrypt hashing to workfactor 18, which takes
about 25 seconds to run on my desktop machine.

1 files changed, 6 insertions, 1 deletions

diff --git a/src/block/blowfish/blowfish.cpp b/src/block/blowfish/blowfish.cpp
index 6610decd8..b6319eec0 100644
--- a/src/block/blowfish/blowfish.cpp
+++ b/src/block/blowfish/blowfish.cpp
@@ -117,7 +117,12 @@ void Blowfish::eks_key_schedule(const byte key[], size_t length,
    if(workfactor == 0)
       throw std::invalid_argument("Bcrypt work factor must be at least 1");
 
-   if(workfactor > 24) // ok?
+   /*
+   * On a 2.8 GHz Core-i7, workfactor == 18 takes about 25 seconds to
+   * hash a password. This seems like a reasonable upper bound for the
+   * time being.
+   */
+   if(workfactor > 18)
       throw std::invalid_argument("Requested Bcrypt work factor too large");
 
    clear();