Fix various crashes (#484)

Author: mickael-menu

.idea/.gitignore

@@ -30,7 +30,7 @@ androidx-lifecycle = "2.7.0"
 androidx-lifecycle-extensions = "2.2.0"
 androidx-media = "1.7.0"
 androidx-media2 = "1.3.0"
-androidx-media3 = "1.3.0-rc01"
+androidx-media3 = "1.3.0"
 androidx-navigation = "2.7.6"
 androidx-paging = "3.2.1"
 androidx-recyclerview = "1.3.2"

gradle/libs.versions.toml

@@ -47,7 +47,10 @@ public class PsPdfKitDocumentFactory(context: Context) : PdfDocumentFactory<PsPd
             } catch (e: InvalidSignatureException) {
                 Try.failure(ReadError.Decoding(ThrowableError(e)))
             } catch (e: IOException) {
-                Try.failure(dataProvider.error!!)
+                Try.failure(
+                    dataProvider.error
+                        ?: ReadError.UnsupportedOperation(ThrowableError(IllegalStateException(e)))
+                )
             }
         }
 }

readium/adapters/pspdfkit/document/src/main/java/org/readium/adapter/pspdfkit/document/PsPdfKitDocument.kt

@@ -14,6 +14,7 @@ import org.readium.r2.shared.extensions.inflate
 import org.readium.r2.shared.extensions.requireLengthFitInt
 import org.readium.r2.shared.publication.encryption.Encryption
 import org.readium.r2.shared.util.DebugError
+import org.readium.r2.shared.util.ThrowableError
 import org.readium.r2.shared.util.Try
 import org.readium.r2.shared.util.Url
 import org.readium.r2.shared.util.data.ReadError
@@ -266,11 +267,27 @@ private suspend fun LcpLicense.decryptFully(
 
         // Removes the padding.
         val padding = bytes.last().toInt()
+        if (padding !in bytes.indices) {
+            return Try.failure(
+                ReadError.Decoding(
+                    DebugError(
+                        "The padding length of the encrypted resource is incorrect: $padding / ${bytes.size}"
+                    )
+                )
+            )
+        }
         bytes = bytes.copyOfRange(0, bytes.size - padding)
 
-        // If the ressource was compressed using deflate, inflates it.
+        // If the resource was compressed using deflate, inflates it.
         if (isDeflated) {
             bytes = bytes.inflate(nowrap = true)
+                .getOrElse {
+                    return Try.failure(
+                        ReadError.Decoding(
+                            DebugError("Cannot deflate the decrypted resource", ThrowableError(it))
+                        )
+                    )
+                }
         }
 
         Try.success(bytes)

readium/lcp/src/main/java/org/readium/r2/lcp/LcpDecryptor.kt

@@ -322,10 +322,12 @@ internal class TtsPlayer<S : TtsEngine.Settings, P : TtsEngine.Preferences<P>,
         }
 
         coroutineScope.launch {
-            playbackJob?.cancel()
-            playbackJob?.join()
-            utteranceMutable.value = utteranceMutable.value.copy(range = null)
-            playIfReadyAndNotPaused()
+            mutex.withLock {
+                playbackJob?.cancel()
+                playbackJob?.join()
+                utteranceMutable.value = utteranceMutable.value.copy(range = null)
+                playIfReadyAndNotPaused()
+            }
         }
     }
 

readium/navigators/media/tts/src/main/java/org/readium/navigator/media/tts/TtsPlayer.kt

@@ -11,8 +11,10 @@ package org.readium.r2.shared.extensions
 
 import java.io.ByteArrayOutputStream
 import java.security.MessageDigest
+import java.util.zip.DataFormatException
 import java.util.zip.Inflater
 import org.readium.r2.shared.InternalReadiumApi
+import org.readium.r2.shared.util.Try
 import timber.log.Timber
 
 /**
@@ -21,18 +23,22 @@ import timber.log.Timber
  * @param nowrap If true then support GZIP compatible compression, see the documentation of [Inflater]
  */
 @InternalReadiumApi
-public fun ByteArray.inflate(nowrap: Boolean = false, bufferSize: Int = 32 * 1024 /* 32 KB */): ByteArray =
-    ByteArrayOutputStream().use { output ->
-        val inflater = Inflater(nowrap)
-        inflater.setInput(this)
-
-        val buffer = ByteArray(bufferSize)
-        while (!inflater.finished()) {
-            val count = inflater.inflate(buffer)
-            output.write(buffer, 0, count)
-        }
+public fun ByteArray.inflate(nowrap: Boolean = false, bufferSize: Int = 32 * 1024 /* 32 KB */): Try<ByteArray, DataFormatException> =
+    try {
+        ByteArrayOutputStream().use { output ->
+            val inflater = Inflater(nowrap)
+            inflater.setInput(this)
 
-        output.toByteArray()
+            val buffer = ByteArray(bufferSize)
+            while (!inflater.finished()) {
+                val count = inflater.inflate(buffer)
+                output.write(buffer, 0, count)
+            }
+
+            Try.success(output.toByteArray())
+        }
+    } catch (e: DataFormatException) {
+        Try.failure(e)
     }
 
 /** Computes the MD5 hash of the byte array. */

readium/shared/src/main/java/org/readium/r2/shared/extensions/ByteArray.kt

@@ -25,6 +25,13 @@ public sealed class ContentResolverError(
         public constructor(exception: Exception) : this(ThrowableError(exception))
     }
 
+    public class Forbidden(
+        cause: Error?
+    ) : ContentResolverError("You are not allowed to access this file.", cause) {
+
+        public constructor(exception: Exception) : this(ThrowableError(exception))
+    }
+
     public class NotAvailable(
         cause: Error? = null
     ) : ContentResolverError("Content Provider recently crashed.", cause) {

readium/shared/src/main/java/org/readium/r2/shared/util/content/ContentResolverError.kt

@@ -150,6 +150,8 @@ public class ContentResource(
             failure(ReadError.Access(ContentResolverError.FileNotFound(e)))
         } catch (e: IOException) {
             failure(ReadError.Access(ContentResolverError.IO(e)))
+        } catch (e: SecurityException) {
+            failure(ReadError.Access(ContentResolverError.Forbidden(e)))
         } catch (e: OutOfMemoryError) { // We don't want to catch any Error, only OOM.
             failure(ReadError.OutOfMemory(e))
         }

readium/shared/src/main/java/org/readium/r2/shared/util/content/ContentResource.kt

@@ -0,0 +1,29 @@
+package org.readium.r2.streamer.extensions
+
+import com.mcxiaoke.koi.HASH
+import com.mcxiaoke.koi.ext.toHexBytes
+import org.readium.r2.shared.extensions.tryOrNull
+
+/**
+ * Computes the SHA-1 hash of a string.
+ */
+internal fun String.sha1(): String =
+    HASH.sha1(this)
+
+/**
+ * Converts an hexadecimal string (e.g. 8ad5078e) to a byte array.
+ */
+internal fun String.toHexByteArray(): ByteArray? {
+    // Only even-length strings can be converted to an Hex byte array, otherwise it crashes
+    // with StringIndexOutOfBoundsException.
+    if (isEmpty() || !hasEvenLength() || !isHexadecimal()) {
+        return null
+    }
+    return tryOrNull { toHexBytes() }
+}
+
+private fun String.hasEvenLength(): Boolean =
+    length % 2 == 0
+
+private fun String.isHexadecimal(): Boolean =
+    all { it in '0'..'9' || it in 'a'..'f' || it in 'A'..'F' }

readium/streamer/src/main/java/org/readium/r2/streamer/extensions/StringExt.kt

@@ -6,15 +6,17 @@
 
 package org.readium.r2.streamer.parser.epub
 
-import com.mcxiaoke.koi.HASH
-import com.mcxiaoke.koi.ext.toHexBytes
 import kotlin.experimental.xor
 import org.readium.r2.shared.publication.encryption.Encryption
+import org.readium.r2.shared.util.Try
 import org.readium.r2.shared.util.Url
+import org.readium.r2.shared.util.data.ReadError
 import org.readium.r2.shared.util.data.ReadTry
 import org.readium.r2.shared.util.resource.Resource
 import org.readium.r2.shared.util.resource.TransformingResource
 import org.readium.r2.shared.util.resource.flatMap
+import org.readium.r2.streamer.extensions.sha1
+import org.readium.r2.streamer.extensions.toHexByteArray
 
 /**
  * Deobfuscates fonts according to https://www.w3.org/TR/epub-33/#sec-font-obfuscation
@@ -49,9 +51,13 @@ internal class EpubDeobfuscator(
                 val obfuscationLength: Int = algorithm2length[algorithm]
                     ?: return@map bytes
 
-                val obfuscationKey: ByteArray = when (algorithm) {
+                val obfuscationKey: ByteArray? = when (algorithm) {
                     "http://ns.adobe.com/pdf/enc#RC" -> getHashKeyAdobe(pubId)
-                    else -> HASH.sha1(pubId).toHexBytes()
+                    else -> pubId.sha1()
+                }.toHexByteArray()
+
+                if (obfuscationKey == null || obfuscationKey.isEmpty()) {
+                    return Try.failure(ReadError.Decoding("The obfuscation key is not valid."))
                 }
 
                 deobfuscate(
@@ -78,5 +84,4 @@ internal class EpubDeobfuscator(
     private fun getHashKeyAdobe(pubId: String) =
         pubId.replace("urn:uuid:", "")
             .replace("-", "")
-            .toHexBytes()
 }

readium/streamer/src/main/java/org/readium/r2/streamer/parser/epub/EpubDeobfuscator.kt

@@ -0,0 +1,26 @@
+package org.readium.r2.streamer.extensions
+
+import kotlin.test.assertContentEquals
+import kotlin.test.assertNull
+import org.junit.Test
+
+class StringExtTest {
+
+    @Test
+    fun `convert an hexadecimal string to a byte array`() {
+        assertNull("".toHexByteArray())
+        // Forbids odd-length strings.
+        assertNull("8".toHexByteArray())
+        assertNull("8ad".toHexByteArray())
+        // Forbids character outside 0-f range.
+        assertNull("8y".toHexByteArray())
+
+        assertContentEquals(byteArrayOf(0x8a), "8a".toHexByteArray())
+        assertContentEquals(byteArrayOf(0x8a), "8A".toHexByteArray())
+        assertContentEquals(byteArrayOf(0x8a, 0xd5, 0x07, 0x8e), "8ad5078e".toHexByteArray())
+    }
+
+    private fun byteArrayOf(vararg bytes: Int): ByteArray {
+        return bytes.map { it.toByte() }.toByteArray()
+    }
+}

readium/streamer/src/test/java/org/readium/r2/streamer/extensions/StringExtTest.kt

@@ -62,7 +62,7 @@ fun HttpError.toUserError(): UserError = when (this) {
 
 fun FileSystemError.toUserError(): UserError = when (this) {
     is FileSystemError.Forbidden -> UserError(
-        R.string.publication_error_filesystem_unexpected,
+        R.string.publication_error_filesystem_forbidden,
         cause = this
     )
     is FileSystemError.IO -> UserError(
@@ -88,5 +88,9 @@ fun ContentResolverError.toUserError(): UserError = when (this) {
         R.string.publication_error_filesystem_unexpected,
         cause = this
     )
+    is ContentResolverError.Forbidden -> UserError(
+        R.string.publication_error_filesystem_forbidden,
+        cause = this
+    )
     is ContentResolverError.NotAvailable -> UserError(R.string.error_unexpected, cause = this)
 }

test-app/src/main/java/org/readium/r2/testapp/domain/ReadUserError.kt

@@ -113,6 +113,7 @@
     <string name="publication_error_network_ssl_handshake">A SSL error occurred.</string>
     <string name="publication_error_network_unexpected">An unexpected network error occurred.</string>
     <string name="publication_error_filesystem_not_found">A file has not been found.</string>
+    <string name="publication_error_filesystem_forbidden">You are not allowed to access the file.</string>
     <string name="publication_error_filesystem_unexpected">An unexpected filesystem error occurred.</string>
     <string name="publication_error_filesystem_insufficient_space">There is not enough space left on the device.</string>
     <string name="publication_error_incorrect_credentials">Provided credentials were incorrect</string>