NAME
signify – cryptographically sign and verify files
SYNOPSIS
signify -C [-q] [-p pubkey] [-t keytype] -x sigfile [file ...]
signify -G [-n] [-c comment] -p pubkey -s seckey
signify -S [-enz] [-x sigfile] -s seckey -m message
signify -V [-eqz] [-p pubkey] [-t keytype] [-x sigfile] -m message
DESCRIPTION
The signify utility creates and verifies cryptographic signatures. A signature verifies the integrity of a message. The mode of operation is selected with the following options:
- -C
-
Verify a signed checksum list, and then verify the checksum for each file. If no files are specified, all of them are checked. sigfile should be the signed output of sha256(1).
- -G
-
Generate a new key pair. Keynames should follow the convention of keyname.pub and keyname.sec for the public and secret keys, respectively.
- -S
-
Sign the specified message file and create a signature.
- -V
-
Verify the message and signature match.
The other options are as follows:
- -c comment
-
Specify the comment to be added during key generation.
- -e
-
When signing, embed the message after the signature. When verifying, extract the message from the signature. (This requires that the signature was created using -e and creates a new message file as output.)
- -m message
-
When signing, the file containing the message to sign. When verifying, the file containing the message to verify. When verifying with -e, the file to create.
- -n
-
When generating a key pair, do not ask for a passphrase. Otherwise, signify will prompt the user for a passphrase to protect the secret key. When signing with -z, store a zero time stamp in the gzip(1) header.
- -p pubkey
-
Public key produced by -G, and used by -V to check a signature.
- -q
-
Quiet mode. Suppress informational output.
- -s seckey
-
Secret (private) key produced by -G, and used by -S to sign a message.
- -t keytype
-
When deducing the correct key to check a signature, make sure the actual key matches /etc/signify/*-keytype.pub.
- -x sigfile
-
The signature file to create or verify. The default is message.sig.
The key and signature files created by signify have the same format. The first line of the file is a free form text comment that may be edited, so long as it does not exceed a single line. Signature comments will be generated based on the name of the secret key used for signing. This comment can then be used as a hint for the name of the public key when verifying. The second line of the file is the actual key or signature base64 encoded.
EXIT STATUS
The signify utility exits 0 on success, and >0 if an error occurs. It may fail because of one of the following reasons:
-
Some necessary files do not exist.
-
Entered passphrase is incorrect.
-
The message file was corrupted and its signature does not match.
-
The message file is too large.
EXAMPLES
Create a new key pair:
$ signify -G -p newkey.pub -s newkey.sec
Sign a file, specifying a signature name:
$ signify -S -s key.sec -m message.txt -x msg.sig
Verify a signature, using the default signature name:
$ signify -V -p key.pub -m generalsorders.txt
Verify a release directory containing SHA256.sig and a full set of release files:
$ signify -C -p /etc/signify/openbsd-80-base.pub -x SHA256.sig
Verify a bsd.rd before an upgrade:
$ signify -C -p /etc/signify/openbsd-80-base.pub -x SHA256.sig bsd.rd
Sign a gzip archive:
$ signify -Sz -s key-arc.sec -m in.tgz -x out.tgz
Verify a gzip pipeline:
$ ftp url | signify -Vz -t arc | tar ztf -
SEE ALSO
gzip(1), pkg_add(1), sha256(1), fw_update(8), sysupgrade(8)
HISTORY
The signify command first appeared in OpenBSD 5.5.
AUTHORS
Ted Unangst ⟨[email protected]⟩ and Marc Espie ⟨[email protected]⟩.