Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2015 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 16 | #include <UniquePtr.h> |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 17 | |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 18 | #include <gatekeeper/gatekeeper.h> |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 19 | |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 20 | namespace gatekeeper { |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 21 | |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 22 | void GateKeeper::Enroll(const EnrollRequest &request, EnrollResponse *response) { |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 23 | if (response == NULL) return; |
| 24 | |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 25 | if (!request.provided_password.buffer.get()) { |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 26 | response->error = ERROR_INVALID; |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 27 | return; |
| 28 | } |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 29 | |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 30 | secure_id_t user_id = 0; |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 31 | |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 32 | if (request.password_handle.buffer.get() == NULL) { |
| 33 | // Password handle does not match what is stored, generate new SecureID |
| 34 | GetRandom(&user_id, sizeof(secure_id_t)); |
| 35 | } else { |
Andres Morales | 426fcfb | 2015-04-01 13:33:45 -0700 | [diff] [blame^] | 36 | password_handle_t *pw_handle = |
| 37 | reinterpret_cast<password_handle_t *>(request.password_handle.buffer.get()); |
| 38 | if (!DoVerify(pw_handle, request.enrolled_password)) { |
| 39 | // incorrect old password |
| 40 | response->error = ERROR_INVALID; |
| 41 | return; |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 42 | } |
Andres Morales | 426fcfb | 2015-04-01 13:33:45 -0700 | [diff] [blame^] | 43 | |
| 44 | user_id = pw_handle->user_id; |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 45 | } |
| 46 | |
| 47 | salt_t salt; |
| 48 | GetRandom(&salt, sizeof(salt)); |
| 49 | |
| 50 | secure_id_t authenticator_id; |
| 51 | GetRandom(&authenticator_id, sizeof(authenticator_id)); |
| 52 | |
| 53 | |
| 54 | SizedBuffer password_handle; |
| 55 | if(!CreatePasswordHandle(&password_handle, |
| 56 | salt, user_id, authenticator_id, request.provided_password.buffer.get(), |
| 57 | request.provided_password.length)) { |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 58 | response->error = ERROR_INVALID; |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 59 | return; |
| 60 | } |
| 61 | |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 62 | response->SetEnrolledPasswordHandle(&password_handle); |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 63 | } |
| 64 | |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 65 | void GateKeeper::Verify(const VerifyRequest &request, VerifyResponse *response) { |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 66 | if (response == NULL) return; |
| 67 | |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 68 | if (!request.provided_password.buffer.get() || !request.password_handle.buffer.get()) { |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 69 | response->error = ERROR_INVALID; |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 70 | return; |
| 71 | } |
| 72 | |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 73 | password_handle_t *password_handle = reinterpret_cast<password_handle_t *>( |
| 74 | request.password_handle.buffer.get()); |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 75 | |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 76 | // Sanity check |
| 77 | if (password_handle->version != HANDLE_VERSION) { |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 78 | response->error = ERROR_INVALID; |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 79 | return; |
| 80 | } |
| 81 | |
Andres Morales | 426fcfb | 2015-04-01 13:33:45 -0700 | [diff] [blame^] | 82 | secure_id_t user_id = password_handle->user_id; |
| 83 | secure_id_t authenticator_id = password_handle->authenticator_id; |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 84 | |
Andres Morales | 11c2a51 | 2015-03-23 10:10:44 -0700 | [diff] [blame] | 85 | uint64_t timestamp = GetNanosecondsSinceBoot(); |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 86 | |
| 87 | if (DoVerify(password_handle, request.provided_password)) { |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 88 | // Signature matches |
| 89 | SizedBuffer auth_token; |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 90 | MintAuthToken(&auth_token.buffer, &auth_token.length, timestamp, |
| 91 | user_id, authenticator_id); |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 92 | response->SetVerificationToken(&auth_token); |
| 93 | } else { |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 94 | response->error = ERROR_INVALID; |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 95 | } |
| 96 | } |
| 97 | |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 98 | bool GateKeeper::CreatePasswordHandle(SizedBuffer *password_handle_buffer, salt_t salt, |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 99 | secure_id_t user_id, secure_id_t authenticator_id, const uint8_t *password, |
Andres Morales | 11ed52a | 2015-03-30 16:47:47 -0700 | [diff] [blame] | 100 | uint32_t password_length) { |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 101 | password_handle_buffer->buffer.reset(new uint8_t[sizeof(password_handle_t)]); |
| 102 | password_handle_buffer->length = sizeof(password_handle_t); |
| 103 | |
| 104 | password_handle_t *password_handle = reinterpret_cast<password_handle_t *>( |
| 105 | password_handle_buffer->buffer.get()); |
| 106 | password_handle->version = HANDLE_VERSION; |
| 107 | password_handle->salt = salt; |
| 108 | password_handle->user_id = user_id; |
| 109 | password_handle->authenticator_id = authenticator_id; |
| 110 | |
Andres Morales | 11ed52a | 2015-03-30 16:47:47 -0700 | [diff] [blame] | 111 | uint32_t metadata_length = sizeof(user_id) /* user id */ |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 112 | + sizeof(authenticator_id) /* auth id */ + sizeof(uint8_t) /* version */; |
| 113 | uint8_t to_sign[password_length + metadata_length]; |
| 114 | memcpy(to_sign, &password_handle->version, metadata_length); |
| 115 | memcpy(to_sign + metadata_length, password, password_length); |
| 116 | |
Andres Morales | f10e289 | 2015-03-23 12:03:56 -0700 | [diff] [blame] | 117 | const uint8_t *password_key = NULL; |
Andres Morales | 11ed52a | 2015-03-30 16:47:47 -0700 | [diff] [blame] | 118 | uint32_t password_key_length = 0; |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 119 | GetPasswordKey(&password_key, &password_key_length); |
| 120 | |
Andres Morales | f10e289 | 2015-03-23 12:03:56 -0700 | [diff] [blame] | 121 | if (!password_key || password_key_length == 0) { |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 122 | return false; |
| 123 | } |
| 124 | |
| 125 | ComputePasswordSignature(password_handle->signature, sizeof(password_handle->signature), |
Andres Morales | f10e289 | 2015-03-23 12:03:56 -0700 | [diff] [blame] | 126 | password_key, password_key_length, to_sign, sizeof(to_sign), salt); |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 127 | return true; |
| 128 | } |
| 129 | |
Andres Morales | 7d0f040 | 2015-03-19 18:02:55 -0700 | [diff] [blame] | 130 | bool GateKeeper::DoVerify(const password_handle_t *expected_handle, const SizedBuffer &password) { |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 131 | if (!password.buffer.get()) return false; |
| 132 | |
| 133 | SizedBuffer provided_handle; |
| 134 | if (!CreatePasswordHandle(&provided_handle, expected_handle->salt, expected_handle->user_id, |
| 135 | expected_handle->authenticator_id, password.buffer.get(), password.length)) { |
| 136 | return false; |
| 137 | } |
| 138 | |
| 139 | return memcmp_s(provided_handle.buffer.get(), expected_handle, sizeof(*expected_handle)) == 0; |
| 140 | } |
| 141 | |
Andres Morales | 11ed52a | 2015-03-30 16:47:47 -0700 | [diff] [blame] | 142 | void GateKeeper::MintAuthToken(UniquePtr<uint8_t> *auth_token, uint32_t *length, |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 143 | uint32_t timestamp, secure_id_t user_id, secure_id_t authenticator_id) { |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 144 | if (auth_token == NULL) return; |
| 145 | |
| 146 | AuthToken *token = new AuthToken; |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 147 | SizedBuffer serialized_auth_token; |
| 148 | |
Andres Morales | 5d39a97 | 2015-03-23 14:54:01 -0700 | [diff] [blame] | 149 | token->auth_token_version = AUTH_TOKEN_VERSION; |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 150 | token->root_secure_user_id = user_id; |
| 151 | token->auxiliary_secure_user_id = authenticator_id; |
Andres Morales | 5d39a97 | 2015-03-23 14:54:01 -0700 | [diff] [blame] | 152 | token->authenticator_id = 0; |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 153 | token->timestamp = timestamp; |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 154 | |
Andres Morales | f10e289 | 2015-03-23 12:03:56 -0700 | [diff] [blame] | 155 | const uint8_t *auth_token_key = NULL; |
Andres Morales | 11ed52a | 2015-03-30 16:47:47 -0700 | [diff] [blame] | 156 | uint32_t key_len = 0; |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 157 | GetAuthTokenKey(&auth_token_key, &key_len); |
| 158 | |
Andres Morales | 11ed52a | 2015-03-30 16:47:47 -0700 | [diff] [blame] | 159 | uint32_t hash_len = (uint32_t)((uint8_t *)&token->hmac - (uint8_t *)token); |
Andres Morales | f10e289 | 2015-03-23 12:03:56 -0700 | [diff] [blame] | 160 | ComputeSignature(token->hmac, sizeof(token->hmac), auth_token_key, key_len, |
Andres Morales | edd3e3d | 2015-03-12 13:30:15 -0700 | [diff] [blame] | 161 | reinterpret_cast<uint8_t *>(token), hash_len); |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 162 | |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 163 | if (length != NULL) *length = sizeof(AuthToken); |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 164 | auth_token->reset(reinterpret_cast<uint8_t *>(token)); |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 165 | } |
Andres Morales | b2abaa8 | 2015-03-03 09:09:18 -0800 | [diff] [blame] | 166 | |
Andres Morales | ac80818 | 2015-02-26 14:11:04 -0800 | [diff] [blame] | 167 | } |