add C API for R4 encryption

git-svn-id: svn+q:///qpdf/trunk@825 71b93d88-0707-0410-a8cf-f5a4172ac649

4 files changed, 58 insertions, 2 deletions

diff --git a/libqpdf/Pl_AES_PDF.cc b/libqpdf/Pl_AES_PDF.cc
index 0ceb7df7..d9754981 100644
--- a/libqpdf/Pl_AES_PDF.cc
+++ b/libqpdf/Pl_AES_PDF.cc
@@ -12,6 +12,8 @@
 # define srandom srand
 #endif
 
+bool Pl_AES_PDF::use_static_iv = false;
+
 Pl_AES_PDF::Pl_AES_PDF(char const* identifier, Pipeline* next,
 		       bool encrypt, unsigned char const key[key_size]) :
     Pipeline(identifier, next),
@@ -52,6 +54,12 @@ Pl_AES_PDF::disableCBC()
 }
 
 void
+Pl_AES_PDF::useStaticIV()
+{
+    use_static_iv = true;
+}
+
+void
 Pl_AES_PDF::write(unsigned char* data, int len)
 {
     unsigned int bytes_left = len;
@@ -116,9 +124,19 @@ Pl_AES_PDF::initializeVector()
 	srandom((int)QUtil::get_current_time() ^ 0xcccc);
 	seeded_random = true;
     }
-    for (unsigned int i = 0; i < this->buf_size; ++i)
+    if (use_static_iv)
+    {
+	for (unsigned int i = 0; i < this->buf_size; ++i)
+	{
+	    this->cbc_block[i] = 14 * (1 + i);
+	}
+    }
+    else
     {
-	this->cbc_block[i] = (unsigned char)((random() & 0xff0) >> 4);
+	for (unsigned int i = 0; i < this->buf_size; ++i)
+	{
+	    this->cbc_block[i] = (unsigned char)((random() & 0xff0) >> 4);
+	}
     }
 }
 
diff --git a/libqpdf/QPDFWriter.cc b/libqpdf/QPDFWriter.cc
index 3c1640f7..320706b0 100644
--- a/libqpdf/QPDFWriter.cc
+++ b/libqpdf/QPDFWriter.cc
@@ -140,6 +140,15 @@ QPDFWriter::setStaticID(bool val)
 }
 
 void
+QPDFWriter::setStaticAesIV(bool val)
+{
+    if (val)
+    {
+	Pl_AES_PDF::useStaticIV();
+    }
+}
+
+void
 QPDFWriter::setSuppressOriginalObjectIDs(bool val)
 {
     this->suppress_original_object_ids = val;
diff --git a/libqpdf/qpdf-c.cc b/libqpdf/qpdf-c.cc
index abc74c95..96de680f 100644
--- a/libqpdf/qpdf-c.cc
+++ b/libqpdf/qpdf-c.cc
@@ -313,6 +313,12 @@ void qpdf_set_static_ID(qpdf_data qpdf, QPDF_BOOL value)
     qpdf->qpdf_writer->setStaticID(value);
 }
 
+void qpdf_set_static_aes_IV(qpdf_data qpdf, QPDF_BOOL value)
+{
+    QTC::TC("qpdf", "qpdf-c called qpdf_set_static_aes_IV");
+    qpdf->qpdf_writer->setStaticAesIV(value);
+}
+
 void qpdf_set_suppress_original_object_IDs(
     qpdf_data qpdf, QPDF_BOOL value)
 {
@@ -356,6 +362,26 @@ void qpdf_set_r3_encryption_parameters(
 	 QPDFWriter::r3m_all));
 }
 
+void qpdf_set_r4_encryption_parameters(
+    qpdf_data qpdf, char const* user_password, char const* owner_password,
+    QPDF_BOOL allow_accessibility, QPDF_BOOL allow_extract,
+    int print, int modify, QPDF_BOOL encrypt_metadata, QPDF_BOOL use_aes)
+{
+    QTC::TC("qpdf", "qpdf-c called qpdf_set_r4_encryption_parameters");
+    qpdf->qpdf_writer->setR4EncryptionParameters(
+	user_password, owner_password,
+	allow_accessibility, allow_extract,
+	((print == QPDF_R3_PRINT_LOW) ? QPDFWriter::r3p_low :
+	 (print == QPDF_R3_PRINT_NONE) ? QPDFWriter::r3p_none :
+	 QPDFWriter::r3p_full),
+	((modify == QPDF_R3_MODIFY_ANNOTATE) ? QPDFWriter::r3m_annotate :
+	 (modify == QPDF_R3_MODIFY_FORM) ? QPDFWriter::r3m_form :
+	 (modify == QPDF_R3_MODIFY_ASSEMBLY) ? QPDFWriter::r3m_assembly :
+	 (modify == QPDF_R3_MODIFY_NONE) ? QPDFWriter::r3m_none :
+	 QPDFWriter::r3m_all),
+	encrypt_metadata, use_aes);
+}
+
 void qpdf_set_linearization(qpdf_data qpdf, QPDF_BOOL value)
 {
     QTC::TC("qpdf", "qpdf-c called qpdf_set_linearization");
diff --git a/libqpdf/qpdf/Pl_AES_PDF.hh b/libqpdf/qpdf/Pl_AES_PDF.hh
index 888ea752..084fca7b 100644
--- a/libqpdf/qpdf/Pl_AES_PDF.hh
+++ b/libqpdf/qpdf/Pl_AES_PDF.hh
@@ -20,12 +20,15 @@ class DLL_EXPORT Pl_AES_PDF: public Pipeline
 
     // For testing only; PDF always uses CBC
     void disableCBC();
+    // For testing only: use a fixed initialization vector for CBC
+    static void useStaticIV();
 
   private:
     void flush(bool discard_padding);
     void initializeVector();
 
     static unsigned int const buf_size = 16;
+    static bool use_static_iv;
 
     bool encrypt;
     bool cbc_mode;