1 /*
2 * Copyright (C) 2016 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 */
16
17 #define LOG_TAG "keystore"
18
19 #include "keystore_utils.h"
20
21 #include <errno.h>
22 #include <string.h>
23 #include <unistd.h>
24
25 #include <log/log.h>
26 #include <private/android_filesystem_config.h>
27 #include <private/android_logger.h>
28
29 #include <log/log_event_list.h>
30
31 #include <keystore/keymaster_types.h>
32 #include <keystore/keystore_client.h>
33
34 #include "blob.h"
35
readFully(int fd,uint8_t * data,size_t size)36 size_t readFully(int fd, uint8_t* data, size_t size) {
37 size_t remaining = size;
38 while (remaining > 0) {
39 ssize_t n = TEMP_FAILURE_RETRY(read(fd, data, remaining));
40 if (n <= 0) {
41 return size - remaining;
42 }
43 data += n;
44 remaining -= n;
45 }
46 return size;
47 }
48
writeFully(int fd,uint8_t * data,size_t size)49 size_t writeFully(int fd, uint8_t* data, size_t size) {
50 size_t remaining = size;
51 while (remaining > 0) {
52 ssize_t n = TEMP_FAILURE_RETRY(write(fd, data, remaining));
53 if (n < 0) {
54 ALOGW("write failed: %s", strerror(errno));
55 return size - remaining;
56 }
57 data += n;
58 remaining -= n;
59 }
60 if (TEMP_FAILURE_RETRY(fsync(fd)) == -1) {
61 ALOGW("fsync failed: %s", strerror(errno));
62 return -1;
63 }
64 return size;
65 }
66
add_legacy_key_authorizations(int keyType,keystore::AuthorizationSet * params)67 void add_legacy_key_authorizations(int keyType, keystore::AuthorizationSet* params) {
68 using namespace keystore;
69 params->push_back(TAG_PURPOSE, KeyPurpose::SIGN);
70 params->push_back(TAG_PURPOSE, KeyPurpose::VERIFY);
71 params->push_back(TAG_PURPOSE, KeyPurpose::ENCRYPT);
72 params->push_back(TAG_PURPOSE, KeyPurpose::DECRYPT);
73 params->push_back(TAG_PADDING, PaddingMode::NONE);
74 if (keyType == EVP_PKEY_RSA) {
75 params->push_back(TAG_PADDING, PaddingMode::RSA_PKCS1_1_5_SIGN);
76 params->push_back(TAG_PADDING, PaddingMode::RSA_PKCS1_1_5_ENCRYPT);
77 params->push_back(TAG_PADDING, PaddingMode::RSA_PSS);
78 params->push_back(TAG_PADDING, PaddingMode::RSA_OAEP);
79 }
80 params->push_back(TAG_DIGEST, Digest::NONE);
81 params->push_back(TAG_DIGEST, Digest::MD5);
82 params->push_back(TAG_DIGEST, Digest::SHA1);
83 params->push_back(TAG_DIGEST, Digest::SHA_2_224);
84 params->push_back(TAG_DIGEST, Digest::SHA_2_256);
85 params->push_back(TAG_DIGEST, Digest::SHA_2_384);
86 params->push_back(TAG_DIGEST, Digest::SHA_2_512);
87 params->push_back(TAG_NO_AUTH_REQUIRED);
88 params->push_back(TAG_ORIGINATION_EXPIRE_DATETIME, LLONG_MAX);
89 params->push_back(TAG_USAGE_EXPIRE_DATETIME, LLONG_MAX);
90 params->push_back(TAG_ACTIVE_DATETIME, 0);
91 }
92
get_app_id(uid_t uid)93 uid_t get_app_id(uid_t uid) {
94 return uid % AID_USER;
95 }
96
get_user_id(uid_t uid)97 uid_t get_user_id(uid_t uid) {
98 return uid / AID_USER;
99 }
100
log_key_integrity_violation(const char * name,uid_t uid)101 void log_key_integrity_violation(const char* name, uid_t uid) {
102 if (!__android_log_security()) return;
103 android_log_event_list(SEC_TAG_KEY_INTEGRITY_VIOLATION)
104 << name << int32_t(uid) << LOG_ID_SECURITY;
105 }
106
107 namespace keystore {
108
blob2hidlVec(const Blob & blob)109 hidl_vec<uint8_t> blob2hidlVec(const Blob& blob) {
110 hidl_vec<uint8_t> result(blob.getValue(), blob.getValue() + blob.getLength());
111 return result;
112 }
113
flagsToSecurityLevel(int32_t flags)114 SecurityLevel flagsToSecurityLevel(int32_t flags) {
115 switch (flags & (KEYSTORE_FLAG_FALLBACK | KEYSTORE_FLAG_STRONGBOX)) {
116 case KEYSTORE_FLAG_FALLBACK:
117 // treating Strongbox flag as "don't care" if Fallback is set
118 case (KEYSTORE_FLAG_FALLBACK | KEYSTORE_FLAG_STRONGBOX):
119 return SecurityLevel::SOFTWARE;
120 case KEYSTORE_FLAG_STRONGBOX:
121 return SecurityLevel::STRONGBOX;
122 default:
123 return SecurityLevel::TRUSTED_ENVIRONMENT;
124 }
125 }
126
securityLevelToFlags(SecurityLevel secLevel)127 uint32_t securityLevelToFlags(SecurityLevel secLevel) {
128 switch (secLevel) {
129 case SecurityLevel::SOFTWARE:
130 return KEYSTORE_FLAG_FALLBACK;
131 case SecurityLevel::STRONGBOX:
132 return KEYSTORE_FLAG_STRONGBOX;
133 default:
134 return 0;
135 }
136 }
137
138 } // namespace keystore
139