| encoding/json | Package json implements encoding and decoding of JSON as defined in RFC 7159. |
| flag | Package flag implements command-line flag parsing. |
| github.com/cloudflare/cfssl/log | Package log implements a wrapper around the Go standard library's logging package. |
| github.com/cloudflare/cfssl/transport | Package transport implements functions for facilitating proper TLS-secured communications for clients and servers. |
| github.com/cloudflare/cfssl/transport/core | Package core contains core definitions for the transport package, the most salient of which is likely the Identity type. |
| github.com/cloudflare/cfssl/transport/example/exlib | Package exlib contains common library code for the examples. |
| io/ioutil | Package ioutil implements some I/O utility functions. |
| net | Package net provides a portable interface for network I/O, including TCP/IP, UDP, domain name resolution, and Unix domain sockets. |