Move crate documentation to README and add code example

Signed-off-by: Wiktor Kwapisiewicz <wiktor@metacode.biz>

cryptoki/README.md

@@ -7,4 +7,77 @@
 
 This is the high-level, Rust idiomatic wrapper crate for PKCS #11.
 
+The items in this crate only expose idiomatic and safe Rust types and
+functions to interface with the PKCS11 API. All the PKCS11 items might
+not be implemented but everything that is implemented is safe.
+
+## Example
+
+The following example initializes an empty token and generates a new RSA key.
+
+```rust
+# fn main() -> testresult::TestResult {
+use cryptoki::object::Attribute;
+use cryptoki::context::{CInitializeArgs, Pkcs11};
+use cryptoki::session::UserType;
+use cryptoki::types::AuthPin;
+use cryptoki::mechanism::Mechanism;
+
+let pkcs11 = Pkcs11::new(
+        std::env::var("PKCS11_SOFTHSM2_MODULE")
+            .unwrap_or_else(|_| "/usr/local/lib/softhsm/libsofthsm2.so".to_string()),
+    )?;
+
+pkcs11.initialize(CInitializeArgs::OsThreads)?;
+
+let slot = pkcs11.get_slots_with_token()?[0];
+
+let so_pin = AuthPin::new("abcdef".into());
+pkcs11.init_token(slot, &so_pin, "Test Token")?;
+
+let user_pin = AuthPin::new("fedcba".into());
+
+{
+  let session = pkcs11.open_rw_session(slot)?;
+  session.login(UserType::So, Some(&so_pin))?;
+  session.init_pin(&user_pin)?;
+}
+
+let session = pkcs11.open_rw_session(slot)?;
+session.login(UserType::User, Some(&user_pin))?;
+
+let pub_key_template = vec![
+    Attribute::Token(true),
+    Attribute::Private(false),
+    Attribute::PublicExponent(vec![0x01, 0x00, 0x01]),
+    Attribute::ModulusBits(1024.into()),
+];
+
+let priv_key_template = vec![Attribute::Token(true)];
+
+let (public, private) = session.generate_key_pair(&Mechanism::RsaPkcsKeyPairGen, &pub_key_template, &priv_key_template)?;
+# Ok(()) }
+```
+
+## Conformance Notes
+
+Throughout this crate, many functions and other items include additional
+"**Conformance**" notes. These notes may provide guarantees about behavior or
+additional, contextual information. In all cases, such items pertain
+to information from the PKCS#11 standard and are contingent on the provider
+being accessed through this crate conforming to that standard. That is, this
+crate is permitted to *assume* these guarantees, and is does not necessarily
+check for or enforce them itself.
+
+## License
+
+This project is licensed under the [Apache License, Version 2.0](https://www.apache.org/licenses/LICENSE-2.0).
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally
+submitted for inclusion in this crate by you, as defined in the
+Apache-2.0 license, shall be licensed as above, without any
+additional terms or conditions.
+
 *Copyright 2021 Contributors to the Parsec project.*

cryptoki/src/lib.rs

@@ -1,23 +1,6 @@
 // Copyright 2021 Contributors to the Parsec project.
 // SPDX-License-Identifier: Apache-2.0
-//! Rust PKCS11 new abstraction
-//!
-//! The items in the new module only expose idiomatic and safe Rust types and functions to
-//! interface with the PKCS11 API. All the PKCS11 items might not be implemented but everything
-//! that is implemented is safe.
-//!
-//! The modules under `new` follow the structure of the PKCS11 document version 2.40 available [here](http://docs.oasis-open.org/pkcs11/pkcs11-base/v2.40/pkcs11-base-v2.40.html).
-//!
-//! # Conformance Notes
-//!
-//! Throughout this crate, many functions and other items include additional
-//! "**Conformance**" notes. These notes may provide guarantees about behavior or
-//! additional, contextual information. In all cases, such items pertain
-//! to information from the PKCS#11 standard and are contingent on the provider
-//! being accessed through this crate conforming to that standard. That is, this
-//! crate is permitted to *assume* these guarantees, and is does not necessarily
-//! check for or enforce them itself.
-
+#![doc = include_str!("../README.md")]
 // This list comes from
 // https://github.com/rust-unofficial/patterns/blob/master/anti_patterns/deny-warnings.md
 #![allow(renamed_and_removed_lints, unknown_lints)]