AES_PDF: switch to pluggable crypto

Jay Berkenbilt
1 parent bb427bd1
Showing 8 changed files with 132 additions and 32 deletions
include/qpdf/QPDFCryptoImpl.hh
libqpdf/AES_PDF_native.cc
libqpdf/Pl_AES_PDF.cc
libqpdf/QPDFCrypto_native.cc
libqpdf/build.mk
libqpdf/qpdf/AES_PDF_native.hh
libqpdf/qpdf/Pl_AES_PDF.hh
libqpdf/qpdf/QPDFCrypto_native.hh
@@ -73,6 +73,15 @@ class QPDF_DLL_CLASS QPDFCryptoImpl
                              unsigned char* out_data = 0) = 0;
     QPDF_DLL
     virtual void RC4_finalize() = 0;
+
+    QPDF_DLL
+    virtual void rijndael_init(
+        bool encrypt, unsigned char const* key_data, size_t key_len) = 0;
+    QPDF_DLL
+    virtual void rijndael_process(
+        unsigned char* in_data, unsigned char* out_data) = 0;
+    QPDF_DLL
+    virtual void rijndael_finalize() = 0;
 };
 #endif // QPDFCRYPTOIMPL_HH
+#include <qpdf/AES_PDF_native.hh>
+#include <qpdf/QUtil.hh>
+#include <cstring>
+#include <assert.h>
+#include <stdexcept>
+#include <qpdf/rijndael.h>
+#include <qpdf/QIntC.hh>
+#include <string>
+#include <stdlib.h>
+
+AES_PDF_native::AES_PDF_native(bool encrypt, unsigned char const* key,
+                               size_t key_bytes) :
+    encrypt(encrypt),
+    nrounds(0)
+{
+    size_t keybits = 8 * key_bytes;
+    this->key = std::unique_ptr<unsigned char[]>(
+        new unsigned char[key_bytes],
+        std::default_delete<unsigned char[]>());
+    this->rk = std::unique_ptr<uint32_t[]>(
+        new uint32_t[RKLENGTH(keybits)],
+        std::default_delete<uint32_t[]>());
+    size_t rk_bytes = RKLENGTH(keybits) * sizeof(uint32_t);
+    std::memcpy(this->key.get(), key, key_bytes);
+    std::memset(this->rk.get(), 0, rk_bytes);
+    if (encrypt)
+    {
+	this->nrounds = rijndaelSetupEncrypt(
+            this->rk.get(), this->key.get(), keybits);
+    }
+    else
+    {
+	this->nrounds = rijndaelSetupDecrypt(
+            this->rk.get(), this->key.get(), keybits);
+    }
+}
+
+AES_PDF_native::~AES_PDF_native()
+{
+}
+
+void
+AES_PDF_native::update(unsigned char* in_data, unsigned char* out_data)
+{
+    if (this->encrypt)
+    {
+	rijndaelEncrypt(this->rk.get(),
+                        this->nrounds, in_data, out_data);
+    }
+    else
+    {
+	rijndaelDecrypt(this->rk.get(),
+                        this->nrounds, in_data, out_data);
+    }
+}
@@ -3,8 +3,8 @@
 #include <cstring>
 #include <assert.h>
 #include <stdexcept>
-#include <qpdf/rijndael.h>
 #include <qpdf/QIntC.hh>
+#include <qpdf/QPDFCryptoProvider.hh>
 #include <string>
 #include <stdlib.h>
@@ -14,38 +14,23 @@ Pl_AES_PDF::Pl_AES_PDF(char const* identifier, Pipeline* next,
 		       bool encrypt, unsigned char const* key,
                        size_t key_bytes) :
     Pipeline(identifier, next),
+    crypto(QPDFCryptoProvider::getImpl()),
     encrypt(encrypt),
     cbc_mode(true),
     first(true),
     offset(0),
-    nrounds(0),
     use_zero_iv(false),
     use_specified_iv(false),
     disable_padding(false)
 {
-    size_t keybits = 8 * key_bytes;
-    assert(key_bytes == KEYLENGTH(keybits));
-    this->key = PointerHolder<unsigned char>(
-        true, new unsigned char[key_bytes]);
-    this->rk = PointerHolder<uint32_t>(
-        true, new uint32_t[RKLENGTH(keybits)]);
-    size_t rk_bytes = RKLENGTH(keybits) * sizeof(uint32_t);
-    std::memcpy(this->key.getPointer(), key, key_bytes);
-    std::memset(this->rk.getPointer(), 0, rk_bytes);
+    this->key = std::unique_ptr<unsigned char[]>(
+        new unsigned char[key_bytes],
+        std::default_delete<unsigned char[]>());
+    std::memcpy(this->key.get(), key, key_bytes);
     std::memset(this->inbuf, 0, this->buf_size);
     std::memset(this->outbuf, 0, this->buf_size);
     std::memset(this->cbc_block, 0, this->buf_size);
-    if (encrypt)
-    {
-	this->nrounds = rijndaelSetupEncrypt(
-            this->rk.getPointer(), this->key.getPointer(), keybits);
-    }
-    else
-    {
-	this->nrounds = rijndaelSetupDecrypt(
-            this->rk.getPointer(), this->key.getPointer(), keybits);
-    }
-    assert(this->nrounds == NROUNDS(keybits));
+    this->crypto->rijndael_init(encrypt, this->key.get(), key_bytes);
 }
 Pl_AES_PDF::~Pl_AES_PDF()
@@ -148,6 +133,7 @@ Pl_AES_PDF::finish()
 	}
 	flush(! this->disable_padding);
     }
+    this->crypto->rijndael_finalize();
     getNext()->finish();
 }
@@ -224,8 +210,7 @@ Pl_AES_PDF::flush(bool strip_padding)
 		this->inbuf[i] ^= this->cbc_block[i];
 	    }
 	}
-	rijndaelEncrypt(this->rk.getPointer(),
-                        this->nrounds, this->inbuf, this->outbuf);
+	this->crypto->rijndael_process(this->inbuf, this->outbuf);
 	if (this->cbc_mode)
 	{
 	    memcpy(this->cbc_block, this->outbuf, this->buf_size);
@@ -233,8 +218,7 @@ Pl_AES_PDF::flush(bool strip_padding)
     }
     else
     {
-	rijndaelDecrypt(this->rk.getPointer(),
-                        this->nrounds, this->inbuf, this->outbuf);
+	this->crypto->rijndael_process(this->inbuf, this->outbuf);
 	if (this->cbc_mode)
 	{
 	    for (unsigned int i = 0; i < this->buf_size; ++i)
@@ -66,3 +66,23 @@ QPDFCrypto_native::SHA2_digest()
 {
     return this->sha2->getRawDigest();
 }
+
+void
+QPDFCrypto_native::rijndael_init(
+    bool encrypt, unsigned char const* key_data, size_t key_len)
+{
+    this->aes_pdf = std::make_shared<AES_PDF_native>(
+        encrypt, key_data, key_len);
+}
+
+void
+QPDFCrypto_native::rijndael_process(unsigned char* in_data,
+                                    unsigned char* out_data)
+{
+    this->aes_pdf->update(in_data, out_data);
+}
+
+void
+QPDFCrypto_native::rijndael_finalize()
+{
+}
@@ -5,6 +5,7 @@ LDFLAGS_libqpdf = -Llibqpdf/$(OUTPUT_DIR)
 LIBS_libqpdf = -lqpdf
 SRCS_libqpdf = \
+	libqpdf/AES_PDF_native.cc \
 	libqpdf/BitStream.cc \
 	libqpdf/BitWriter.cc \
 	libqpdf/Buffer.cc \
+#ifndef AES_PDF_NATIVE_HH
+#define AES_PDF_NATIVE_HH
+
+#include <cstdint>
+#include <cstring>
+#include <memory>
+
+class AES_PDF_native
+{
+  public:
+    // key should be a pointer to key_bytes bytes of data
+    AES_PDF_native(bool encrypt, unsigned char const* key,
+                   size_t key_bytes);
+    ~AES_PDF_native();
+
+    void update(unsigned char* in_data, unsigned char* out_data);
+
+  private:
+    bool encrypt;
+    std::unique_ptr<unsigned char[]> key;
+    std::unique_ptr<uint32_t[]> rk;
+    unsigned int nrounds;
+};
+
+#endif // AES_PDF_NATIVE_HH
@@ -3,9 +3,8 @@
 #include <qpdf/Pipeline.hh>
 #include <qpdf/qpdf-config.h>
-#ifdef HAVE_STDINT_H
-# include <stdint.h>
-#endif
+#include <qpdf/QPDFCryptoImpl.hh>
+#include <memory>
 // This pipeline implements AES-128 and AES-256 with CBC and block
 // padding as specified in the PDF specification.
@@ -51,17 +50,16 @@ class Pl_AES_PDF: public Pipeline
     static unsigned int const buf_size = 16;
     static bool use_static_iv;
+    std::shared_ptr<QPDFCryptoImpl> crypto;
     bool encrypt;
     bool cbc_mode;
     bool first;
     size_t offset;              // offset into memory buffer
-    PointerHolder<unsigned char> key;
-    PointerHolder<uint32_t> rk;
+    std::unique_ptr<unsigned char[]> key;
     unsigned char inbuf[buf_size];
     unsigned char outbuf[buf_size];
     unsigned char cbc_block[buf_size];
     unsigned char specified_iv[buf_size];
-    unsigned int nrounds;
     bool use_zero_iv;
     bool use_specified_iv;
     bool disable_padding;
@@ -6,6 +6,7 @@
 #include <qpdf/MD5_native.hh>
 #include <qpdf/RC4_native.hh>
 #include <qpdf/SHA2_native.hh>
+#include <qpdf/AES_PDF_native.hh>
 #include <memory>
 class QPDFCrypto_native: public QPDFCryptoImpl
@@ -31,10 +32,17 @@ class QPDFCrypto_native: public QPDFCryptoImpl
     virtual void SHA2_finalize();
     virtual std::string SHA2_digest();
+    virtual void rijndael_init(
+        bool encrypt, unsigned char const* key_data, size_t key_len);
+    virtual void rijndael_process(
+        unsigned char* in_data, unsigned char* out_data);
+    virtual void rijndael_finalize();
+
   private:
     std::shared_ptr<MD5_native> md5;
     std::shared_ptr<RC4_native> rc4;
     std::shared_ptr<SHA2_native> sha2;
+    std::shared_ptr<AES_PDF_native> aes_pdf;
 };
 #endif // QPDFCRYPTO_NATIVE_HH