verify(1)

NAME
verify - Verifies signed messages or detached signatures

SYNOPSIS
verify [-o|--output] [--detached] [-n|--signatures] [--signer-file] [--signer-cert] [-h|--help] [FILE]

DESCRIPTION
Verifies signed messages or detached signatures

When verifying signed messages, the message is written to stdout or the file given to --output.

When a detached message is verified, no output is produced. Detached signatures are often used to sign software packages.

Verification is only successful if there is no bad signature, and the number of successfully verified signatures reaches the threshold configured with the "--signatures" parameter. If the verification fails, the program terminates with an exit status indicating failure. In addition to that, the last 25 MiB of the message are withheld, i.e. if the message is smaller than 25 MiB, no output is produced, and if it is larger, then the output will be truncated.

A signature is considered to have been authenticated if the signer can be authenticated. If the signer is provided via "--signer-file", then the signer is considered authenticated. Otherwise, the signer is looked up and authenticated using the web of trust. If at least one User ID can be fully authenticated, then the signature is considered to have been authenticated. If the signature includes a Signer User ID subpacket, then only that User ID is considered. Note: the User ID need not be self signed.

The converse operation is "sq sign".

If you are looking for a standalone program to verify detached signatures, consider using sequoia-sqv.

"sq verify" respects the reference time set by the top-level "--time" argument. When set, it verifies the message as of the reference time instead of the current time.

OPTIONS

-o, --output=FILE
    Writes to FILE or stdout if omitted

--detached=SIG
    Verifies a detached signature

-n, --signatures=N [default: 1]
    Sets the threshold of valid signatures to N. If this threshold is not reached, the message will not be considered verified.

--signer-file=CERT_FILE
    Verifies signatures using the certificate in CERT_FILE

--signer-cert=FINGERPRINT|KEYID
    Verifies signatures using the specified certificate. This reads the certificate from the certificate store, and considers it to be authenticated. When this option is not provided, the certificate is still read from the certificate store, if it exists, but it is not considered authenticated.

-h, --help
    Print help information (use `-h` for a summary)

[FILE]
    Reads from FILE or stdin if omitted

EXTRA
EXAMPLES: # Verify a signed message $ sq verify --signer-file juliet.pgp signed-message.pgp # Verify a detached message $ sq verify --signer-file juliet.pgp --detached message.sig message.txt # Verify a message as of June 9, 2011 at midnight UTC: $ sq verify --time 20130721 msg.pgp