IDEA-160341 secure implementation of joinData

platform/credential-store/src/credentialStore.kt

@@ -17,6 +17,8 @@ package com.intellij.credentialStore
 
 import com.intellij.openapi.diagnostic.Logger
 import com.intellij.openapi.util.text.StringUtil
+import org.jetbrains.io.toByteArray
+import java.nio.CharBuffer
 import java.security.MessageDigest
 import java.util.*
 
@@ -28,11 +30,23 @@ internal fun toOldKeyAsIdentity(hash: ByteArray) = CredentialAttributes("Intelli
 
 fun toOldKey(requestor: Class<*>, userName: String) = CredentialAttributes("IntelliJ Platform", toOldKey(MessageDigest.getInstance("SHA-256").digest("${requestor.name}/$userName".toByteArray())))
 
-fun joinData(user: String?, password: OneTimeString?): String? {
+fun joinData(user: String?, password: OneTimeString?): ByteArray? {
   if (user == null && password == null) {
     return null
   }
-  return "${StringUtil.escapeChars(user.orEmpty(), '\\', '@')}${if (password == null) "" else "@$password"}"
+
+  val builder = StringBuilder(user.orEmpty())
+  StringUtil.escapeChar(builder, '\\')
+  StringUtil.escapeChar(builder, '@')
+  if (password != null) {
+    builder.append('@')
+    password.appendTo(builder)
+  }
+
+  val buffer = Charsets.UTF_8.encode(CharBuffer.wrap(builder))
+  // clear password
+  builder.setLength(0)
+  return buffer.toByteArray()
 }
 
 fun splitData(data: String?): Credentials? {
@@ -78,4 +92,4 @@ private fun parseString(data: String, delimiter: Char): List<String> {
 }
 
 // check isEmpty before
-fun Credentials.serialize() = joinData(userName, password)!!.toByteArray()
+fun Credentials.serialize() = joinData(userName, password)!!

platform/credential-store/src/libraries/linuxSecretLibrary.kt

@@ -13,10 +13,13 @@ private const val SECRET_SCHEMA_NONE = 0
 private const val SECRET_SCHEMA_ATTRIBUTE_STRING = 0
 
 // explicitly create pointer to be explicitly dispose it to avoid sensitive data in the memory
-internal fun stringPointer(data: ByteArray): DisposableMemory {
+internal fun stringPointer(data: ByteArray, clearInput: Boolean = false): DisposableMemory {
   val pointer = DisposableMemory(data.size + 1L)
   pointer.write(0, data, 0, data.size)
   pointer.setByte(data.size.toLong(), 0.toByte())
+  if (clearInput) {
+    data.fill(0)
+  }
   return pointer
 }
 
@@ -74,7 +77,7 @@ internal class SecretCredentialStore(schemeName: String) : CredentialStore {
       return
     }
 
-    val passwordPointer = stringPointer(credentials!!.serialize())
+    val passwordPointer = stringPointer(credentials!!.serialize(), true)
     checkError("secret_password_store_sync") { errorRef ->
       try {
         if (accountName == null) {

platform/credential-store/test/CredentialSerializeTest.kt

@@ -27,7 +27,7 @@ class CredentialSerializeTest {
 
   private fun test(u: String?, p: String?, joined: String) {
     val pass = p?.let(::OneTimeString)
-    assertThat(joinData(u, pass)).isEqualTo(joined)
+    assertThat(joinData(u, pass)).isEqualTo(joined.toByteArray())
     assertThat(splitData(joined)).isEqualTo(Credentials(u, pass))
   }
 }

platform/platform-api/src/com/intellij/credentialStore/CredentialAttributes.kt

@@ -127,4 +127,11 @@ class OneTimeString @JvmOverloads constructor(value: CharArray, offset: Int = 0,
     }
     return super.equals(other)
   }
+
+  fun appendTo(builder: StringBuilder) {
+    if (consumed.get()) {
+      throw Error("Already consumed")
+    }
+    builder.append(myChars, myStart, length)
+  }
 }

platform/util/src/com/intellij/openapi/util/text/StringUtil.java

@@ -2135,7 +2135,7 @@ public class StringUtil extends StringUtilRt {
     return buf.toString();
   }
 
-  private static void escapeChar(@NotNull final StringBuilder buf, final char character) {
+  public static void escapeChar(@NotNull final StringBuilder buf, final char character) {
     int idx = 0;
     while ((idx = indexOf(buf, character, idx)) >= 0) {
       buf.insert(idx, "\\");