| crypto | Package crypto collects common cryptographic constants. |
| crypto/x509 | Package x509 implements a subset of the X.509 standard. |
| encoding/base64 | Package base64 implements base64 encoding as specified by RFC 4648. |
| encoding/json | Package json implements encoding and decoding of JSON as defined in RFC 7159. |
| encoding/pem | Package pem implements the PEM data encoding, which originated in Privacy Enhanced Mail. |
| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| github.com/Sirupsen/logrus | |
| github.com/docker/distribution/context | Package context provides several utilities for working with Go's context in http requests. |
| github.com/docker/distribution/registry/auth | Package auth defines a standard interface for request access controllers. |
| github.com/docker/libtrust | Package libtrust provides an interface for managing authentication and authorization using public key cryptography. |
| golang.org/x/net/context | Package context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes. |
| io/ioutil | Package ioutil implements some I/O utility functions. |
| net/http | Package http provides HTTP client and server implementations. |
| os | Package os provides a platform-independent interface to operating system functionality. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| time | Package time provides functionality for measuring and displaying time. |