Port to binderized keymaster HAL
This patch ports keystore to the HIDL based binderized keymaster HAL.
Keystore has no more dependencies on legacy keymaster headers, and
therefore data structures, constant declarations, or enums. All
keymaster related data structures and enums used by keystore are the
once defined by the HIDL based keymaster HAL definition. In the process
of porting, keystore underwent some changes:
* Keystore got a new implementation of AuthorizationSet that is fully
based on the new HIDL data structures. Key parameters are now either
organised as AuthorizationSets or hidl_vec<KeyParameter>. (Formerly,
this was a mixture of keymaster's AuthorizationSet,
std::vec<keymaster_key_param_t>, and keymaster_key_param_set_t.) The
former is used for memory management and provides algorithms for
assembling, joining, and subtracting sets of parameters. The latter
is used as wire format for the HAL IPC; it can wrap the memory owned
by an AuthorizationSet for this purpose. The AuthorizationSet is
accompanied by a new implementation of type safe functions for
creating and accessing tagged key parameters,
Authorizations (keystore/keymaster_tags.h).
* A new type (KSSReturnCode) was introduced that wraps keystore service
response codes. Keystore has two sets of error codes. ErrorCode
errors are less than 0 and use 0 as success value. ResponseCode
errors are greater than zero and use 1 as success value. This patch
changes ResponseCode to be an enum class so that is no longer
assignable to int without a cast. The new return type can only be
initialized by ResponseCode or ErrorCode and when accessed as int32_t,
which happens on serialization when the response is send to a client,
the success values are coalesced onto 1 as expected by the
clients. KSSreturnCode is also comparable to ResponseCode and
ErrorCode, and the predicate isOk() returns true if it was initialized
with either ErrorCode::OK (0) or ReponseCode::NO_ERROR (1).
* A bug was fixed, that caused the keystore verify function to return
success, regardless of the input, internal errors, or lack of
permissions.
* The marshalling code in IKeystoreService.cpp was rewritten. For data
structures that are known to keymaster, the client facing side of
keystore uses HIDL based data structures as (target) source
for (un)marshaling to avoid further conversion. hidl_vecs are used to
wrap parcel memory without copying and taking ownership where
possible.
* Explicit use of malloc is reduced (malloc was required by the C nature
of the old HAL). The new implementations avoid explicit use of
malloc/new and waive the use of pointers for return values. Instead,
functions return by value objects that take ownership of secondary
memory allocations where required.
Test: runtest --path=cts/tests/tests/keystore/src/android/keystore/cts
Bug: 32020919
Change-Id: I59d3a0f4a6bdf6bb3bbf791ad8827c463effa286
diff --git a/keystore/user_state.cpp b/keystore/user_state.cpp
index 3da88c2..bd4f979 100644
--- a/keystore/user_state.cpp
+++ b/keystore/user_state.cpp
@@ -31,7 +31,9 @@
#include "blob.h"
#include "keystore_utils.h"
-UserState::UserState(uid_t userId) : mUserId(userId), mRetry(MAX_RETRY) {
+
+UserState::UserState(uid_t userId) :
+ mUserId(userId), mState(STATE_UNINITIALIZED), mRetry(MAX_RETRY) {
asprintf(&mUserDir, "user_%u", mUserId);
asprintf(&mMasterKeyFile, "%s/.masterkey", mUserDir);
}
@@ -78,22 +80,22 @@
ResponseCode UserState::initialize(const android::String8& pw, Entropy* entropy) {
if (!generateMasterKey(entropy)) {
- return SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
ResponseCode response = writeMasterKey(pw, entropy);
- if (response != NO_ERROR) {
+ if (response != ResponseCode::NO_ERROR) {
return response;
}
setupMasterKeys();
- return ::NO_ERROR;
+ return ResponseCode::NO_ERROR;
}
ResponseCode UserState::copyMasterKey(UserState* src) {
if (mState != STATE_UNINITIALIZED) {
- return ::SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
if (src->getState() != STATE_NO_ERROR) {
- return ::SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
memcpy(mMasterKey, src->mMasterKey, MASTER_KEY_SIZE_BYTES);
setupMasterKeys();
@@ -106,28 +108,28 @@
*/
int in = TEMP_FAILURE_RETRY(open(src->getMasterKeyFileName(), O_RDONLY));
if (in < 0) {
- return ::SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
blob rawBlob;
size_t length = readFully(in, (uint8_t*)&rawBlob, sizeof(rawBlob));
if (close(in) != 0) {
- return ::SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
int out =
TEMP_FAILURE_RETRY(open(mMasterKeyFile, O_WRONLY | O_TRUNC | O_CREAT, S_IRUSR | S_IWUSR));
if (out < 0) {
- return ::SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
size_t outLength = writeFully(out, (uint8_t*)&rawBlob, length);
if (close(out) != 0) {
- return ::SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
if (outLength != length) {
ALOGW("blob not fully written %zu != %zu", outLength, length);
unlink(mMasterKeyFile);
- return ::SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
- return ::NO_ERROR;
+ return ResponseCode::NO_ERROR;
}
ResponseCode UserState::writeMasterKey(const android::String8& pw, Entropy* entropy) {
@@ -142,7 +144,7 @@
ResponseCode UserState::readMasterKey(const android::String8& pw, Entropy* entropy) {
int in = TEMP_FAILURE_RETRY(open(mMasterKeyFile, O_RDONLY));
if (in < 0) {
- return SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
// We read the raw blob to just to get the salt to generate the AES key, then we create the Blob
@@ -150,7 +152,7 @@
blob rawBlob;
size_t length = readFully(in, (uint8_t*)&rawBlob, sizeof(rawBlob));
if (close(in) != 0) {
- return SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
// find salt at EOF if present, otherwise we have an old file
uint8_t* salt;
@@ -165,18 +167,18 @@
AES_set_decrypt_key(passwordKey, MASTER_KEY_SIZE_BITS, &passwordAesKey);
Blob masterKeyBlob(rawBlob);
ResponseCode response = masterKeyBlob.readBlob(mMasterKeyFile, &passwordAesKey, STATE_NO_ERROR);
- if (response == SYSTEM_ERROR) {
+ if (response == ResponseCode::SYSTEM_ERROR) {
return response;
}
- if (response == NO_ERROR && masterKeyBlob.getLength() == MASTER_KEY_SIZE_BYTES) {
+ if (response == ResponseCode::NO_ERROR && masterKeyBlob.getLength() == MASTER_KEY_SIZE_BYTES) {
// If salt was missing, generate one and write a new master key file with the salt.
if (salt == NULL) {
if (!generateSalt(entropy)) {
- return SYSTEM_ERROR;
+ return ResponseCode::SYSTEM_ERROR;
}
response = writeMasterKey(pw, entropy);
}
- if (response == NO_ERROR) {
+ if (response == ResponseCode::NO_ERROR) {
memcpy(mMasterKey, masterKeyBlob.getValue(), MASTER_KEY_SIZE_BYTES);
setupMasterKeys();
}
@@ -184,20 +186,20 @@
}
if (mRetry <= 0) {
reset();
- return UNINITIALIZED;
+ return ResponseCode::UNINITIALIZED;
}
--mRetry;
switch (mRetry) {
case 0:
- return WRONG_PASSWORD_0;
+ return ResponseCode::WRONG_PASSWORD_0;
case 1:
- return WRONG_PASSWORD_1;
+ return ResponseCode::WRONG_PASSWORD_1;
case 2:
- return WRONG_PASSWORD_2;
+ return ResponseCode::WRONG_PASSWORD_2;
case 3:
- return WRONG_PASSWORD_3;
+ return ResponseCode::WRONG_PASSWORD_3;
default:
- return WRONG_PASSWORD_3;
+ return ResponseCode::WRONG_PASSWORD_3;
}
}