From a42a4068b5ebdf557d2815ee1c72a27ebfefd3f5 Mon Sep 17 00:00:00 2001
From: Jay Berkenbilt <ejb@ql.org>
Date: Wed, 10 Aug 2011 19:47:18 -0400
Subject: [PATCH] preserve /EncryptMetadata when copying encryption parameters

---
 ChangeLog             |  5 +++++
 libqpdf/QPDFWriter.cc |  8 ++++++++
 qpdf/qpdf.testcov     |  1 +
 qpdf/qtest/qpdf.test  | 13 +++++++++++--
 4 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 5fdb0464..454cf44c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2011-08-10  Jay Berkenbilt  <ejb@ql.org>
 
+	* libqpdf/QPDFWriter.cc (copyEncryptionParameters): preserve
+	whether metadata is encryption.  This fixes part of bug 3173659:
+	the password becomes invalid if qpdf copies an encrypted file with
+	cleartext-metadata.
+
 	* include/qpdf/QPDFWriter.hh: add a new constructor that takes
 	only a QPDF reference and leaves specification of output for
 	later.  Add methods setOutputFilename() to set the output to a
diff --git a/libqpdf/QPDFWriter.cc b/libqpdf/QPDFWriter.cc
index 7217ded7..99433a16 100644
--- a/libqpdf/QPDFWriter.cc
+++ b/libqpdf/QPDFWriter.cc
@@ -383,6 +383,14 @@ QPDFWriter::copyEncryptionParameters()
 	{
 	    key_len = encrypt.getKey("/Length").getIntValue() / 8;
 	}
+	if (encrypt.hasKey("/EncryptMetadata") &&
+	    encrypt.getKey("/EncryptMetadata").isBool())
+	{
+	    this->encrypt_metadata =
+		encrypt.getKey("/EncryptMetadata").getBoolValue();
+	}
+	QTC::TC("qpdf", "QPDFWriter copy encrypt metadata",
+		this->encrypt_metadata ? 0 : 1);
 	setEncryptionParametersInternal(
 	    V,
 	    encrypt.getKey("/R").getIntValue(),
diff --git a/qpdf/qpdf.testcov b/qpdf/qpdf.testcov
index 37ad350a..8f5d15a3 100644
--- a/qpdf/qpdf.testcov
+++ b/qpdf/qpdf.testcov
@@ -193,3 +193,4 @@ QPDF stream with CR only 0
 QPDF stream with CRNL 0
 QPDF stream with NL only 0
 QPDF replaceObject called with indirect object 0
+QPDFWriter copy encrypt metadata 1
diff --git a/qpdf/qtest/qpdf.test b/qpdf/qtest/qpdf.test
index de82ce3b..c428aec3 100644
--- a/qpdf/qtest/qpdf.test
+++ b/qpdf/qtest/qpdf.test
@@ -755,7 +755,7 @@ $td->runtest("show-xref-by-id-filtered",
 show_ntests();
 # ----------
 $td->notify("--- Clear-text Metadata Tests ---");
-$n_tests += 42;
+$n_tests += 58;
 
 # args: file, exp_encrypted, exp_cleartext
 check_metadata("compressed-metadata.pdf", 0, 0);
@@ -787,13 +787,22 @@ foreach my $f (qw(compressed-metadata.pdf enc-base.pdf))
 			  " a.pdf b.pdf"},
 		     {$td->STRING => "", $td->EXIT_STATUS => 0});
 	check_metadata("b.pdf", 1, 1);
-	unlink "b.pdf";
+	$td->runtest("preserve encryption",
+		     {$td->COMMAND => "qpdf b.pdf c.pdf"},
+		     {$td->STRING => "", $td->EXIT_STATUS => 0});
+	check_metadata("c.pdf", 1, 1);
+	unlink "b.pdf", "c.pdf";
 	$td->runtest("encrypt with aes and cleartext metadata",
 		     {$td->COMMAND =>
 			  "qpdf --encrypt '' '' 128" .
 			  " --cleartext-metadata --use-aes=y -- a.pdf b.pdf"},
 		     {$td->STRING => "", $td->EXIT_STATUS => 0});
 	check_metadata("b.pdf", 1, 1);
+	$td->runtest("preserve encryption",
+		     {$td->COMMAND => "qpdf b.pdf c.pdf"},
+		     {$td->STRING => "", $td->EXIT_STATUS => 0});
+	check_metadata("c.pdf", 1, 1);
+	unlink "b.pdf", "c.pdf";
     }
 }