D-LAN

h1. SHA-1 prototype

h2. Goals

* Compute the SHA-1 of each part of a given file.

* Compute the SHA-1 for a given part of a given file.

* Compute the SHA-1 of a stream.

h2. Speed measures

*file* : 01.wmv : 17'639'245 byte ~ 17Mo

h3. sha1sum from GNU coreutils (Reference)

speed : 173 MB/s

<pre>

<gburri@overnux:~/code/lang/haskell/SHA1$> time sha1sum < 01.wmv

3aec84601612e8c604ac01971e0ecd9d536dbead  -

real    0m0.098s

user    0m0.092s

sys     0m0.004s

</pre>

h3. "SHA 1.2.0":http://hackage.haskell.org/cgi-bin/hackage-scripts/package/SHA-1.2.0

file : _Hash.hs_

speed : 18 times slower (13 MB/s)

<pre>

<gburri@overnux:~/code/lang/haskell/SHA1$> ghc --make -O2 Hash.hs -o hash && time ./hash 01.wmv

[0 - 3aec84601612e8c604ac01971e0ecd9d536dbead]

real    0m1.244s

user    0m1.212s

sys     0m0.036s$

</pre>

h3. "Crypto 4.2.0":http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Crypto-4.2.0

file : _Hash2.hs_

speed : 267 times slower (1 MB/s) :

<pre>

<gburri@overnux:~/code/lang/haskell/SHA1$> ghc --make -O2 Hash2.hs -o hash2 && time ./hash2 01.wmv

[0 - Word160 988578912 370337990 78381463 504286621 1399701165]

real    0m17.078s

user    0m16.921s

sys     0m0.072s

</pre>

h3. Binding with sha1.h from coreutils

file : _Hash3.hs_

TODO...