Certigo is a utility to examine and validate certificates in a variety of formats.

To install certigo, simply use:

go get -u github.com/square/certigo

Note that certigo requires Go 1.6 or later to build.

We use glide for managing vendored dependencies.

Certigo can read certificates/keystores in various formats and dump them to stdout.

Currently supported formats are DER, PEM, JCEKS/JKS and PKCS12. Certigo will display information in a human-readable way, and print warnings for common mistakes (such as small key sizes or weak signatures/hash functions). Certigo can also convert any input to a series of PEM blocks, which is useful if you want to e.g. dump the contents of PKCS12/JCEKS keystores into something more useful.

usage: certigo [<flags>] <command> [<args> ...]

A command line certificate examination utility.

Flags:
  --help     Show context-sensitive help (also try --help-long and --help-man).
  --version  Show application version.

Commands:
  help [<command>...]
    Show help.

  dump [<flags>] [<file>...]
    Display information about a certificate.

  connect [<flags>] [<server:port>]
    Connect to a server and print its certificate.

  pem [<flags>] [<file>...]
    Convert input to PEM-formatted blocks.

Display information about a certificate (from a file, or from stdin):

Export certificates/keys from a JCEKS/PKCS12 keystore into PEM blocks:

Display information about a certificate from a remote server: