Update username validation to use libsignal.

app/src/main/java/org/thoughtcrime/securesms/profiles/manage/UsernameEditFragment.java

@@ -182,7 +182,7 @@ public class UsernameEditFragment extends LoggingFragment {
       case DISCRIMINATOR_TOO_LONG -> getString(R.string.UsernameEditFragment__invalid_username_enter_a_maximum_of_d_digits, UsernameUtil.MAX_DISCRIMINATOR_LENGTH);
       case DISCRIMINATOR_TOO_SHORT -> getString(R.string.UsernameEditFragment__invalid_username_enter_a_minimum_of_d_digits, UsernameUtil.MIN_DISCRIMINATOR_LENGTH);
       case DISCRIMINATOR_CANNOT_BE_00 -> getString(R.string.UsernameEditFragment__this_number_cant_be_00);
-      case DISCRIMINATOR_CANNOT_START_WITH_00 -> getString(R.string.UsernameEditFragment__this_number_cant_start_with_00);
+      case DISCRIMINATOR_CANNOT_START_WITH_0 -> getString(R.string.UsernameEditFragment__this_number_cant_start_with_0);
     };
 
     int colorRes = error != null ? R.color.signal_colorError : R.color.signal_colorPrimary;

app/src/main/java/org/thoughtcrime/securesms/profiles/manage/UsernameEditViewModel.kt

@@ -22,7 +22,7 @@ import org.thoughtcrime.securesms.profiles.manage.UsernameRepository.UsernameSet
 import org.thoughtcrime.securesms.util.NetworkUtil
 import org.thoughtcrime.securesms.util.UsernameUtil.InvalidReason
 import org.thoughtcrime.securesms.util.UsernameUtil.checkDiscriminator
-import org.thoughtcrime.securesms.util.UsernameUtil.checkUsername
+import org.thoughtcrime.securesms.util.UsernameUtil.checkNickname
 import org.thoughtcrime.securesms.util.rx.RxStore
 import org.whispersystems.signalservice.api.util.Usernames
 import java.util.concurrent.TimeUnit
@@ -159,7 +159,7 @@ internal class UsernameEditViewModel private constructor(private val mode: Usern
       return
     }
 
-    val invalidReason: InvalidReason? = checkUsername(usernameState.getNickname())
+    val invalidReason: InvalidReason? = checkNickname(usernameState.getNickname())
     if (invalidReason != null) {
       Log.w(TAG, "Username was submitted, but did not pass validity checks. Reason: $invalidReason")
       uiState.update { it.copy(buttonState = ButtonState.SUBMIT_DISABLED, usernameStatus = mapNicknameError(invalidReason)) }
@@ -257,7 +257,7 @@ internal class UsernameEditViewModel private constructor(private val mode: Usern
       return
     }
 
-    val invalidReason: InvalidReason? = checkUsername(nickname)
+    val invalidReason: InvalidReason? = checkNickname(nickname)
     if (invalidReason != null) {
       uiState.update { uiState ->
         uiState.copy(
@@ -366,7 +366,7 @@ internal class UsernameEditViewModel private constructor(private val mode: Usern
     DISCRIMINATOR_TOO_LONG,
     DISCRIMINATOR_HAS_INVALID_CHARACTERS,
     DISCRIMINATOR_CANNOT_BE_00,
-    DISCRIMINATOR_CANNOT_START_WITH_00
+    DISCRIMINATOR_CANNOT_START_WITH_0
   }
 
   enum class ButtonState {
@@ -394,7 +394,9 @@ internal class UsernameEditViewModel private constructor(private val mode: Usern
         InvalidReason.TOO_LONG -> UsernameStatus.TOO_LONG
         InvalidReason.STARTS_WITH_NUMBER -> UsernameStatus.CANNOT_START_WITH_NUMBER
         InvalidReason.INVALID_CHARACTERS -> UsernameStatus.INVALID_CHARACTERS
-        InvalidReason.INVALID_NUMBER, InvalidReason.INVALID_NUMBER_PREFIX -> error("Unexpected reason $invalidReason")
+        InvalidReason.INVALID_NUMBER,
+        InvalidReason.INVALID_NUMBER_00,
+        InvalidReason.INVALID_NUMBER_PREFIX_0 -> error("Unexpected reason $invalidReason")
       }
     }
 
@@ -403,8 +405,8 @@ internal class UsernameEditViewModel private constructor(private val mode: Usern
         InvalidReason.TOO_SHORT -> UsernameStatus.DISCRIMINATOR_TOO_SHORT
         InvalidReason.TOO_LONG -> UsernameStatus.DISCRIMINATOR_TOO_LONG
         InvalidReason.INVALID_CHARACTERS -> UsernameStatus.DISCRIMINATOR_HAS_INVALID_CHARACTERS
-        InvalidReason.INVALID_NUMBER -> UsernameStatus.DISCRIMINATOR_CANNOT_BE_00
-        InvalidReason.INVALID_NUMBER_PREFIX -> UsernameStatus.DISCRIMINATOR_CANNOT_START_WITH_00
+        InvalidReason.INVALID_NUMBER_00 -> UsernameStatus.DISCRIMINATOR_CANNOT_BE_00
+        InvalidReason.INVALID_NUMBER_PREFIX_0 -> UsernameStatus.DISCRIMINATOR_CANNOT_START_WITH_0
         else -> UsernameStatus.INVALID_GENERIC
       }
     }

app/src/main/java/org/thoughtcrime/securesms/util/UsernameUtil.kt

@@ -1,6 +1,19 @@
 package org.thoughtcrime.securesms.util
 
 import org.signal.core.util.logging.Log
+import org.signal.libsignal.usernames.BadDiscriminatorCharacterException
+import org.signal.libsignal.usernames.BadNicknameCharacterException
+import org.signal.libsignal.usernames.BaseUsernameException
+import org.signal.libsignal.usernames.CannotBeEmptyException
+import org.signal.libsignal.usernames.CannotStartWithDigitException
+import org.signal.libsignal.usernames.DiscriminatorCannotBeEmptyException
+import org.signal.libsignal.usernames.DiscriminatorCannotBeSingleDigitException
+import org.signal.libsignal.usernames.DiscriminatorCannotBeZeroException
+import org.signal.libsignal.usernames.DiscriminatorCannotHaveLeadingZerosException
+import org.signal.libsignal.usernames.DiscriminatorTooLargeException
+import org.signal.libsignal.usernames.NicknameTooLongException
+import org.signal.libsignal.usernames.NicknameTooShortException
+import org.signal.libsignal.usernames.Username
 import java.util.Locale
 import java.util.regex.Pattern
 
@@ -36,52 +49,75 @@ object UsernameUtil {
   }
 
   @JvmStatic
-  fun checkUsername(value: String?): InvalidReason? {
-    return when {
-      value == null -> {
-        InvalidReason.TOO_SHORT
-      }
-      value.length < MIN_NICKNAME_LENGTH -> {
-        InvalidReason.TOO_SHORT
-      }
-      value.length > MAX_NICKNAME_LENGTH -> {
-        InvalidReason.TOO_LONG
-      }
-      DIGIT_START_PATTERN.matcher(value).matches() -> {
-        InvalidReason.STARTS_WITH_NUMBER
-      }
-      !FULL_PATTERN.matcher(value).matches() -> {
-        InvalidReason.INVALID_CHARACTERS
-      }
-      else -> {
-        null
-      }
+  fun checkNickname(value: String?): InvalidReason? {
+    if (value == null) {
+      return InvalidReason.TOO_SHORT
+    }
+
+    return try {
+      // We only want to check the nickname, so we pass in a known-valid discriminator
+      Username.fromParts(value, "01", MIN_NICKNAME_LENGTH, MAX_NICKNAME_LENGTH)
+      null
+    } catch (e: BadNicknameCharacterException) {
+      InvalidReason.INVALID_CHARACTERS
+    } catch (e: CannotBeEmptyException) {
+      InvalidReason.TOO_SHORT
+    } catch (e: CannotStartWithDigitException) {
+      InvalidReason.STARTS_WITH_NUMBER
+    } catch (e: NicknameTooLongException) {
+      InvalidReason.TOO_LONG
+    } catch (e: NicknameTooShortException) {
+      InvalidReason.TOO_SHORT
+    } catch (e: BaseUsernameException) {
+      Log.w(TAG, "Unhandled verification exception!", e)
+      InvalidReason.INVALID_CHARACTERS
     }
   }
 
   fun checkDiscriminator(value: String?): InvalidReason? {
-    return when {
-      value == null -> {
-        null
-      }
-      value == "00" -> {
-        InvalidReason.INVALID_NUMBER
-      }
-      value.startsWith("00") -> {
-        InvalidReason.INVALID_NUMBER_PREFIX
-      }
-      value.length < MIN_DISCRIMINATOR_LENGTH -> {
+    if (value == null) {
+      return null
+    }
+
+    if (value.length < MIN_DISCRIMINATOR_LENGTH) {
+      return InvalidReason.TOO_SHORT
+    }
+
+    if (value.length > MAX_DISCRIMINATOR_LENGTH) {
+      return InvalidReason.TOO_LONG
+    }
+
+    return try {
+      // We only want to check the discriminator, so we pass in a known-valid nickname
+      Username.fromParts("spiderman", value, MIN_NICKNAME_LENGTH, MAX_NICKNAME_LENGTH)
+      null
+    } catch (e: BadDiscriminatorCharacterException) {
+      InvalidReason.INVALID_CHARACTERS
+    } catch (e: DiscriminatorCannotBeEmptyException) {
+      InvalidReason.TOO_SHORT
+    } catch (e: DiscriminatorCannotBeSingleDigitException) {
+      InvalidReason.TOO_SHORT
+    } catch (e: DiscriminatorCannotBeZeroException) {
+      if (value.length < 2) {
         InvalidReason.TOO_SHORT
+      } else if (value == "00") {
+        InvalidReason.INVALID_NUMBER_00
+      } else {
+        InvalidReason.INVALID_NUMBER_PREFIX_0
       }
-      value.length > MAX_DISCRIMINATOR_LENGTH -> {
-        InvalidReason.TOO_LONG
-      }
-      value.toIntOrNull() == null -> {
-        InvalidReason.INVALID_CHARACTERS
-      }
-      else -> {
-        null
+    } catch (e: DiscriminatorCannotHaveLeadingZerosException) {
+      if (value.length < 2) {
+        InvalidReason.TOO_SHORT
+      } else if (value == "00") {
+        InvalidReason.INVALID_NUMBER_00
+      } else {
+        InvalidReason.INVALID_NUMBER_PREFIX_0
       }
+    } catch (e: DiscriminatorTooLargeException) {
+      InvalidReason.TOO_LONG
+    } catch (e: BaseUsernameException) {
+      Log.w(TAG, "Unhandled verification exception!", e)
+      InvalidReason.INVALID_CHARACTERS
     }
   }
 
@@ -91,6 +127,7 @@ object UsernameUtil {
     INVALID_CHARACTERS,
     STARTS_WITH_NUMBER,
     INVALID_NUMBER,
-    INVALID_NUMBER_PREFIX
+    INVALID_NUMBER_00,
+    INVALID_NUMBER_PREFIX_0
   }
 }