NAME

nbsvtool — create and verify detached signatures of files

SYNOPSIS

nbsvtool

[-v] [-a anchor-certificates] [-c certificate-chain] [-f certificate-file] [-k private-key-file] [-u required-key-usage] command args ...

DESCRIPTION

nbsvtool is used to create and verify detached X509 signatures of files. Private keys and certificates are expected to be PEM encoded, signatures are in PEM/SMIME format.

Supported commands:

sign file

Sign file, placing the signature in file.sp7. The options -f and -k are required for this command.

verify file [signature]

Verify signature for file. If signature is not specified, file.sp7 is used.

verify-code file [signature]

This is a short cut for verify with the option -u code.

Supported options:

-a anchor-certificates

A file containing one or more (concatenated) keys that are considered trusted.

-c certificate-chain

A file containing additional certificates that will be added to the signature when creating one. They will be used to fill missing links in the trust chain when verifying the signature.

-f certificate-file

A file containing the certificate to use for signing. The certificate must match the key given by -k.

-k private-key-file

A file containing the private key to use for signing.

-u required-key-usage

Verify that the extended key-usage attribute in the signing certificate matches required-key-usage. Otherwise, the signature is rejected. key usage can be one of: “ssl-server”, “ssl-client”, “code”, or “smime”.

-v

Print verbose information about the signing certificate.

EXIT STATUS

The nbsvtool utility exits 0 on success, and >0 if an error occurs.

EXAMPLES

Create signature file hello.sp7 for file hello. The private key is found in file key, the matching certificate is in cert, additional certificates from cert-chain are included in the created signature.

nbsvtool -k key -f cert -c cert-chain sign hello hello.sp7

Verify that the signature hello.sp7 is valid for file hello and that the signing certificate allows code signing. Certificates in anchor-file are considered trusted, and there must be a certificate chain from one of those certificates to the signing certificate.

nbsvtool -a anchor-file verify-code hello hello.sp7

SEE ALSO

openssl_smime(1)

CAVEATS

As there is currently no default trust anchor, you must explicilty specify one with -a, otherwise no verification can succeed.