diff --git a/main/filesystem-crypto/src/main/java/org/cryptomator/filesystem/crypto/ConflictResolver.java b/main/filesystem-crypto/src/main/java/org/cryptomator/filesystem/crypto/ConflictResolver.java index 19dceb326..6b8a1f428 100644 --- a/main/filesystem-crypto/src/main/java/org/cryptomator/filesystem/crypto/ConflictResolver.java +++ b/main/filesystem-crypto/src/main/java/org/cryptomator/filesystem/crypto/ConflictResolver.java @@ -2,6 +2,7 @@ package org.cryptomator.filesystem.crypto; import static org.cryptomator.filesystem.crypto.Constants.DIR_PREFIX; +import java.nio.ByteBuffer; import java.util.Optional; import java.util.UUID; import java.util.function.Function; @@ -12,7 +13,7 @@ import java.util.regex.Pattern; import org.apache.commons.lang3.StringUtils; import org.cryptomator.filesystem.File; import org.cryptomator.filesystem.Folder; -import org.cryptomator.io.FileContents; +import org.cryptomator.filesystem.ReadableFile; import org.slf4j.Logger; import org.slf4j.LoggerFactory; @@ -20,6 +21,7 @@ final class ConflictResolver { private static final Logger LOG = LoggerFactory.getLogger(ConflictResolver.class); private static final int UUID_FIRST_GROUP_STRLEN = 8; + private static final int MAX_DIR_FILE_SIZE = 87; // "normal" file header has 88 bytes private final Pattern encryptedNamePattern; private final Function> nameDecryptor; @@ -52,13 +54,11 @@ final class ConflictResolver { if (cleartext.isPresent()) { Folder folder = conflictingFile.parent().get(); File canonicalFile = folder.file(isDirectory ? DIR_PREFIX + ciphertext : ciphertext); - if (canonicalFile.exists()) { + if (isDirectory && canonicalFile.exists() && isSameFileBasedOnSample(canonicalFile, conflictingFile, MAX_DIR_FILE_SIZE)) { // there must not be two directories pointing to the same directory id. In this case no human interaction is needed to resolve this conflict: - if (isDirectory && FileContents.UTF_8.readContents(canonicalFile).equals(FileContents.UTF_8.readContents(conflictingFile))) { - conflictingFile.delete(); - return canonicalFile; - } - + conflictingFile.delete(); + return canonicalFile; + } else { // conventional conflict detected! look for an alternative name: File alternativeFile; String conflictId; @@ -71,9 +71,6 @@ final class ConflictResolver { LOG.info("Detected conflict {}:\n{}\n{}", conflictId, canonicalFile, conflictingFile); conflictingFile.moveTo(alternativeFile); return alternativeFile; - } else { - conflictingFile.moveTo(canonicalFile); - return canonicalFile; } } else { // not decryptable; false positive @@ -81,6 +78,22 @@ final class ConflictResolver { } } + private boolean isSameFileBasedOnSample(File file1, File file2, int sampleSize) { + try (ReadableFile r1 = file1.openReadable(); ReadableFile r2 = file2.openReadable()) { + if (r1.size() != r2.size()) { + return false; + } else { + ByteBuffer beginOfFile1 = ByteBuffer.allocate(sampleSize); + ByteBuffer beginOfFile2 = ByteBuffer.allocate(sampleSize); + r1.read(beginOfFile1); + r2.read(beginOfFile2); + beginOfFile1.flip(); + beginOfFile2.flip(); + return beginOfFile1.equals(beginOfFile2); + } + } + } + private String createConflictId() { return UUID.randomUUID().toString().substring(0, UUID_FIRST_GROUP_STRLEN); }