Workbook on Digital Private Papers > How-Tos

How-Tos

Hasher 0.3

The hasher interface allows the user to browse to the root of the folder containing the files for which hash values are to be calculated or verified and creates a list of files found in the directory and any subdirectories. The user must specify a target file to store the hash values created, or which contains previously calculated hash values to use in verifying the files.

Hasher 0.3

Navigating to the target file, the user can view the hash values calculated, the hash function used to calculate them and the filename path produced by the Calculate Hashes option:

Z:\crypto\work>cat hasher.lst
7efe0618c2cb218b22a61abeec0a5ed9e56e6a4c ?SHA1*METS.xml
b68c1f95fc244be4268a1b56f885118ccf9b7e84 ?SHA1*My Documents/Music/08_ThieveryCorporation_DC3000.mp3
9f6ff27ce93bae21501ac7f2f9acb7326be66d2f ?SHA1*My Documents/Music/Mine/MyAlbumCover.jpg
61d8e9c3e8e1a9f9cc1dbe690bc528ea33d9cd80 ?SHA1*My Documents/Music/Mine/MyAlbumLyrics.txt
696ba86ec1dde088dbaf340b8f42418491ffcda0 ?SHA1*My Documents/School/Schedule.xls

Selecting Verify Hashes compares the contents of the target file with the current contents:

Hasher 0.3

In this example an error is detected for MyAlbumLyrics.txt, which has been modified and therefore has no hash value, and paradigm.gif is not verified as this has been added to the directory and hasher has no existing hash value to verify it:

Hasher 0.3

More information about Jacksum and Hasher is available from their websites: http://sourceforge.net/projects/jacksum/ and http://sourceforge.net/projects/hashergui/