【发布时间】：2020-10-14 01:24:15
【问题描述】：
这就是我想要做的：
- 在 Android 手机上生成 RSA 密钥
- 将公钥导出到 linux 机器
- 使用 OpenSSL 和该公钥加密消息
- 在安卓手机上获取消息，解密并阅读。
我认为我在 Android 上处理了密钥生成：
fun createKeys() {
val kpg = KeyPairGenerator.getInstance(KeyProperties.KEY_ALGORITHM_RSA, "AndroidKeyStore")
val ks = KeyStore.getInstance("AndroidKeyStore").apply {
load(null)
}
val parameterSpec = KeyGenParameterSpec.Builder(
"my_alias",
KeyProperties.PURPOSE_DECRYPT or KeyProperties.PURPOSE_ENCRYPT
).run {
setDigests(KeyProperties.DIGEST_SHA256, KeyProperties.DIGEST_SHA512)
setKeySize(2048)
setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_RSA_PKCS1)
setCertificateSubject(X500Principal("CN=My_CN, O=My_O"))
build()
}
kpg.initialize(parameterSpec)
kpg.generateKeyPair()
}
fun exportPubKey() {
val privateKeyEntry = keyStore.getEntry("my_alias", null) as KeyStore.PrivateKeyEntry
val publicKey = privateKeyEntry.certificate.publicKey
val encoded = String(Base64.encode(publicKey.encoded, Base64.DEFAULT))
// write to file key.pub
}
fun decrypt() {
// read from file file.enc
val privateKeyEntry =
keyStore.getEntry("my_alias", null) as
KeyStore.PrivateKeyEntry
val privateKey = privateKeyEntry.privateKey
val cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding",
"AndroidKeyStoreBCWorkaround")
cipher.init(Cipher.DECRYPT_MODE, privateKey)
val message = cipher.doFinal(Base64.decode(file.toString(),
Base64.DEFAULT))
}
Note: within the app, I'm able to encrypt into a file and decrypt with the code above
在 linux 盒子上：
$ openssl rsautl -encrypt -pkcs -pubin -inkey key.pub -in file.txt -out temp.enc
$ openssl -e -base64 -in temp.enc -out file.enc
I then push the file to the Android phone, run the app, but I'm getting:
FATAL EXCEPTION: main
Process: com.test.key, PID: 28034
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.test.key/com.test.key.MainActivity}: javax.crypto.IllegalBlockSizeException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3270)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
Caused by: javax.crypto.IllegalBlockSizeException
at android.security.keystore.AndroidKeyStoreCipherSpiBase.engineDoFinal(AndroidKeyStoreCipherSpiBase.java:519)
at javax.crypto.Cipher.doFinal(Cipher.java:2055)
at com.test.key.MainActivity.decrypt(MainActivity.kt:190)
at com.test.key.MainActivity.onCreate(MainActivity.kt:92)
at android.app.Activity.performCreate(Activity.java:7825)
at android.app.Activity.performCreate(Activity.java:7814)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1306)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3245)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
Caused by: android.security.KeyStoreException: Unknown error
at android.security.KeyStore.getKeyStoreException(KeyStore.java:1303)
at android.security.keystore.KeyStoreCryptoOperationChunkedStreamer.doFinal(KeyStoreCryptoOperationChunkedStreamer.java:224)
at android.security.keystore.AndroidKeyStoreCipherSpiBase.engineDoFinal(AndroidKeyStoreCipherSpiBase.java:506)
at javax.crypto.Cipher.doFinal(Cipher.java:2055)
at com.test.key.MainActivity.decrypt(MainActivity.kt:190)
at com.test.key.MainActivity.onCreate(MainActivity.kt:92)
at android.app.Activity.performCreate(Activity.java:7825)
at android.app.Activity.performCreate(Activity.java:7814)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1306)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3245)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
【问题讨论】：
-
它适用于我使用 Android 模拟器。但是，如果我改为将空的 base64 字符串 "" 提供给解密过程，我会得到与您相同的错误。我注意到您的第二个 openssl 命令不正确。也许您的测试流程没有识别这一点并生成一个空的密码文件。
-
通常，问题出在屏幕和椅子之间。每当启动应用程序时都会调用生成新密钥的代码。
标签： android encryption openssl rsa