Question

i need to reproduce in python what perl does

  # perl
  perl -e'use Digest::HMAC_SHA1 qw(hmac_sha1_hex); my $hmac = hmac_sha1_hex("string1", "string2"); print $hmac . "\n";'
  25afd2da17e81972b535d15ebae464e291fb3635


  #python
  python -c 'import sha; import hmac; print hmac.new("string1", "string2", sha).hexdigest()'
  3953fa89b3809b8963b514999b2d27a7cdaacc77

as you can see the hex digest is not the same … how can I reproduce the perl code in python ?

thanks !

Answer 1

Python’s HMAC constructor just takes the key and the message in the opposite order — Python’s hmac takes the key first, Perl’s Digest::HMAC takes the key second.

python -c 'import sha; import hmac; print hmac.new("string2", "string1", sha).hexdigest()'
25afd2da17e81972b535d15ebae464e291fb3635

Matches your Perl example just fine 🙂