glite-ssss-split-key

glite-ssss-split-key — Splits a key into shares to be distributed among untrusted parties.

Synopsis

glite-ssss-split-key [ -h ] [ -q ] [ -V ] SHARES NEEDED KEY

DESCRIPTION

glite-ssss-split-key is a command-line tool to split a key into a number of shares using Shamir's Secret Sharing Scheme (see "How to Share a Secret", by Adi Shamir, Communications of the ACM, November, 1979, Volume 22, Number 11, page 612.).

The key is split into SHARES number of parts of which NEEDED number of parts are needed to re-construct the key. The re-construction of the key is theoretically not possible of parts fewer than NEEDED, thus it enables the safe storage of key parts on not fully trusted key storages.

The scheme also provides some reliability, since not all parts of the split key are needed to re-construct the original key.

OPTIONS

-h

Print a short help message on parameters and usage, and exit.

-q

Quiet operation.

-V

Print the version number and exit.

SHARES

The number of parts to split the key into.

NEEDED

The number of split key parts needed to re-construct the key. Shall be less than SHARES.

KEY

The key to split as hexadecimal number. The number of hexadecimal numbers must be greater than 4 and must be dividable by 4 (for example 8, 12, 16 are good key lengths).

ENVIRONMENT VARIABLES

GLITE_SSSS_LOG_LEVEL

Specifies the level of the log messages printed: DEBUG, INFO, WARN or ERROR (default, if not defined).

GLITE_SSSS_LOG_FILE

Specifies the file, where messages are printed. Defaults to stdout, if not defined.

SEE ALSO

glite-ssss-join-key(1)

EXAMPLES

glite-ssss-split-key 5 2 1234567812345678
glite-ssss-split-key 7 3 12345678