Verifying Integrity of File Transfers

Most unix-based systems provide several command-line utilities for computing hashes of files. These hashes can be used to verify file integrity by calculating the hash value before and after the file transfer.

Some commonly-available hash function utilities on unix-based systems:

  • md5sum (or md5 on Mac OSX)

  • shasum

  • sha256sum (or shasum -a 256 on Mac OSX)

Any of these options should suffice for a basic file integrity check.

These commands all share a common syntax:

On the user’s local machine, compute the hash:

~$ shasum my_container.lxc
f1925f822c5ae7b6df5bc8354a2d8534c64fbcd1  my_container.lxc

Compute the hash of the uploaded file:

user@file-proxy:~$ shasum my_container.lxc
f1925f822c5ae7b6df5bc8354a2d8534c64fbcd1  my_container.lxc

References

See the man pages of each command for more information:

man md5sum (or man md5 on Mac OSX)
man shasum
man sha256sum