// Package crypto implements AWS S3 related cryptographic building blocks
// for implementing Server-Side-Encryption (SSE-S3) and Server-Side-Encryption
// with customer provided keys (SSE-C).
//
// All objects are encrypted with an unique and randomly generated 'ObjectKey'.
// The ObjectKey itself is never stored in plaintext. Instead it is only stored

duration of a C function call. Memory may be pinned more than once and
must be unpinned exactly the same number of times it has been pinned.

Go code may pass a Go pointer to C provided the memory to which it
points does not contain any Go pointers to memory that is unpinned. When
passing a pointer to a field in a struct, the Go memory in question is