1 // Licensed to the Apache Software Foundation (ASF) under one
2 // or more contributor license agreements. See the NOTICE file
3 // distributed with this work for additional information
4 // regarding copyright ownership. The ASF licenses this file
5 // to you under the Apache License, Version 2.0 (the
6 // "License"); you may not use this file except in compliance
7 // with the License. You may obtain a copy of the License at
8 //
9 // http://www.apache.org/licenses/LICENSE-2.0
10 //
11 // Unless required by applicable law or agreed to in writing,
12 // software distributed under the License is distributed on an
13 // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
14 // KIND, either express or implied. See the License for the
15 // specific language governing permissions and limitations
16 // under the License.
17
18 #![no_std]
19 #![no_main]
20 #![feature(c_size_t)]
21
22 extern crate alloc;
23
24 use alloc::boxed::Box;
25 use optee_utee::{
26 ta_close_session, ta_create, ta_destroy, ta_invoke_command, ta_open_session, trace_println,
27 };
28 use optee_utee::{AlgorithmId, DeriveKey};
29 use optee_utee::{AttributeId, AttributeMemref, TransientObject, TransientObjectType};
30 use optee_utee::{Error, ErrorKind, Parameters, Result};
31 use proto::{Command, KEY_SIZE};
32
33 pub struct DiffieHellman {
34 pub key: TransientObject,
35 }
36
37 impl Default for DiffieHellman {
default() -> Self38 fn default() -> Self {
39 Self {
40 key: TransientObject::null_object(),
41 }
42 }
43 }
44
45 #[ta_create]
create() -> Result<()>46 fn create() -> Result<()> {
47 trace_println!("[+] TA create");
48 Ok(())
49 }
50
51 #[ta_open_session]
open_session(_params: &mut Parameters, _sess_ctx: &mut DiffieHellman) -> Result<()>52 fn open_session(_params: &mut Parameters, _sess_ctx: &mut DiffieHellman) -> Result<()> {
53 trace_println!("[+] TA open session");
54 Ok(())
55 }
56
57 #[ta_close_session]
close_session(_sess_ctx: &mut DiffieHellman)58 fn close_session(_sess_ctx: &mut DiffieHellman) {
59 trace_println!("[+] TA close session");
60 }
61
62 #[ta_destroy]
destroy()63 fn destroy() {
64 trace_println!("[+] TA destroy");
65 }
66
generate_key(dh: &mut DiffieHellman, params: &mut Parameters) -> Result<()>67 fn generate_key(dh: &mut DiffieHellman, params: &mut Parameters) -> Result<()> {
68 let mut p0 = unsafe { params.0.as_memref().unwrap() };
69 let mut p1 = unsafe { params.1.as_value().unwrap() };
70 let mut p2 = unsafe { params.2.as_memref().unwrap() };
71 let mut p3 = unsafe { params.3.as_memref().unwrap() };
72
73 // Extract prime and base from parameters
74 let prime_base_vec = p0.buffer();
75 let prime_slice = &prime_base_vec[..KEY_SIZE/8];
76 let base_slice = &prime_base_vec[KEY_SIZE/8..];
77
78 let attr_prime = AttributeMemref::from_ref(AttributeId::DhPrime, prime_slice);
79 let attr_base = AttributeMemref::from_ref(AttributeId::DhBase, base_slice);
80
81 // Generate key pair
82 dh.key = TransientObject::allocate(TransientObjectType::DhKeypair, KEY_SIZE).unwrap();
83 let mut public_buffer = p2.buffer();
84 let mut private_buffer = p3.buffer();
85
86 dh.key
87 .generate_key(KEY_SIZE, &[attr_prime.into(), attr_base.into()])?;
88 let mut key_size = dh
89 .key
90 .ref_attribute(AttributeId::DhPublicValue, &mut public_buffer)
91 .unwrap();
92 p1.set_a(key_size as u32);
93 key_size = dh
94 .key
95 .ref_attribute(AttributeId::DhPrivateValue, &mut private_buffer)
96 .unwrap();
97 p1.set_b(key_size as u32);
98 Ok(())
99 }
100
derive_key(dh: &mut DiffieHellman, params: &mut Parameters) -> Result<()>101 fn derive_key(dh: &mut DiffieHellman, params: &mut Parameters) -> Result<()> {
102 let mut p0 = unsafe { params.0.as_memref().unwrap() };
103 let mut p1 = unsafe { params.1.as_memref().unwrap() };
104 let mut p2 = unsafe { params.2.as_value().unwrap() };
105
106 let received_public = AttributeMemref::from_ref(AttributeId::DhPublicValue, p0.buffer());
107
108 match DeriveKey::allocate(AlgorithmId::DhDeriveSharedSecret, KEY_SIZE) {
109 Err(e) => Err(e),
110 Ok(operation) => {
111 operation.set_key(&dh.key)?;
112 let mut derived_key =
113 TransientObject::allocate(TransientObjectType::GenericSecret, KEY_SIZE).unwrap();
114 operation.derive(&[received_public.into()], &mut derived_key);
115 let key_size = derived_key
116 .ref_attribute(AttributeId::SecretValue, p1.buffer())
117 .unwrap();
118 p2.set_a(key_size as u32);
119 Ok(())
120 }
121 }
122 }
123
124 #[ta_invoke_command]
invoke_command( sess_ctx: &mut DiffieHellman, cmd_id: u32, params: &mut Parameters, ) -> Result<()>125 fn invoke_command(
126 sess_ctx: &mut DiffieHellman,
127 cmd_id: u32,
128 params: &mut Parameters,
129 ) -> Result<()> {
130 trace_println!("[+] TA invoke command");
131 match Command::from(cmd_id) {
132 Command::GenerateKey => {
133 return generate_key(sess_ctx, params);
134 }
135 Command::DeriveKey => {
136 return derive_key(sess_ctx, params);
137 }
138 _ => Err(Error::new(ErrorKind::BadParameters)),
139 }
140 }
141
142 // TA configurations
143 const TA_FLAGS: u32 = 0;
144 const TA_DATA_SIZE: u32 = 32 * 1024;
145 const TA_STACK_SIZE: u32 = 2 * 1024;
146 const TA_VERSION: &[u8] = b"0.1\0";
147 const TA_DESCRIPTION: &[u8] = b"This is an example which serves DH related functions.\0";
148 const EXT_PROP_VALUE_1: &[u8] = b"DH TA\0";
149 const EXT_PROP_VALUE_2: u32 = 0x0010;
150 const TRACE_LEVEL: i32 = 4;
151 const TRACE_EXT_PREFIX: &[u8] = b"TA\0";
152 const TA_FRAMEWORK_STACK_SIZE: u32 = 2048;
153
154 include!(concat!(env!("OUT_DIR"), "/user_ta_header.rs"));
155