gware (previously gopherware) is a diceware passphrase generator implemented in pure go. gware can except any wordlist that follows the same format as the standard diceware list (take a look at worldlists, it can also generate just the diceware numbers.
gware's number generator uses go's crypto/rand
package which is a cryptographically secure pseudo random number generator (CSPRNG), the true nature of go's CSPRNG is actually a wrapper for your operating system's CSPRNG. Numbers generated from a CSPRNG are suitable for many cryptographic operations. Knowing this is it safe? Yes! If you ultra paranoid stick with the standard method of a set of casino die and paper.
go get github.com/brsmsn/gware
cd gware
go build cmd/gware/gware.go
Usage : ./gware [-h] [-l N] [-e N] [-n] [-b] wordList
Parameters:
-h Help, get cli parameters
-l N Generate passphrases with N amount of words (Default is 7 words)
-e N Extend number of generated passphrases to N passphrases (Default is 10 passphrases)
-n Number only, output only diceware numbers (a diceware number is a number from 11111 to 66666), this flag will ignore wordlist
-b Block format only, each line corresponds to a passphrase
Passphrases are outputed to stdout.