Add OpenSSL/BoringSSL crypto provider

Fixes qpdf/qpdf#417

1 files changed, 193 insertions, 0 deletions

diff --git a/libqpdf/QPDFCrypto_openssl.cc b/libqpdf/QPDFCrypto_openssl.cc
new file mode 100644
index 00000000..c226fc9c
--- /dev/null
+++ b/libqpdf/QPDFCrypto_openssl.cc
@@ -0,0 +1,193 @@
+#include <qpdf/QPDFCrypto_openssl.hh>
+
+#include <cstring>
+#include <stdexcept>
+
+#include <qpdf/QIntC.hh>
+
+
+static void
+bad_bits(int bits)
+{
+    throw std::logic_error(
+        std::string("unsupported key length: ") + std::to_string(bits));
+}
+
+static void
+check_openssl(int status)
+{
+    if (status != 1)
+    {
+        throw std::runtime_error("openssl error");
+    }
+}
+
+QPDFCrypto_openssl::QPDFCrypto_openssl() :
+    md_ctx(EVP_MD_CTX_new()), cipher_ctx(EVP_CIPHER_CTX_new())
+{
+    memset(md_out, 0, sizeof(md_out));
+    EVP_MD_CTX_init(md_ctx);
+    EVP_CIPHER_CTX_init(cipher_ctx);
+}
+
+QPDFCrypto_openssl::~QPDFCrypto_openssl()
+{
+    EVP_MD_CTX_reset(md_ctx);
+    EVP_CIPHER_CTX_reset(cipher_ctx);
+    EVP_CIPHER_CTX_free(cipher_ctx);
+    EVP_MD_CTX_free(md_ctx);
+}
+
+void
+QPDFCrypto_openssl::MD5_init()
+{
+    check_openssl(EVP_MD_CTX_reset(md_ctx));
+    check_openssl(EVP_DigestInit_ex(md_ctx, EVP_md5(), nullptr));
+}
+
+void
+QPDFCrypto_openssl::SHA2_init(int bits)
+{
+    const EVP_MD* md = EVP_sha512();
+    switch (bits)
+    {
+      case 256:
+        md = EVP_sha256();
+        break;
+      case 384:
+        md = EVP_sha384();
+        break;
+      case 512:
+        md = EVP_sha512();
+        break;
+      default:
+        bad_bits(bits);
+        return;
+    }
+    sha2_bits = static_cast<size_t>(bits);
+    check_openssl(EVP_MD_CTX_reset(md_ctx));
+    check_openssl(EVP_DigestInit_ex(md_ctx, md, nullptr));
+}
+
+void
+QPDFCrypto_openssl::MD5_update(unsigned char const* data, size_t len)
+{
+    check_openssl(EVP_DigestUpdate(md_ctx, data, len));
+}
+
+void
+QPDFCrypto_openssl::SHA2_update(unsigned char const* data, size_t len)
+{
+    check_openssl(EVP_DigestUpdate(md_ctx, data, len));
+}
+
+void
+QPDFCrypto_openssl::MD5_finalize()
+{
+    if (EVP_MD_CTX_md(md_ctx))
+    {
+        check_openssl(EVP_DigestFinal(md_ctx, md_out + 0, nullptr));
+    }
+}
+
+void
+QPDFCrypto_openssl::SHA2_finalize()
+{
+    if (EVP_MD_CTX_md(md_ctx))
+    {
+         check_openssl(EVP_DigestFinal(md_ctx, md_out + 0, nullptr));
+    }
+}
+
+void
+QPDFCrypto_openssl::MD5_digest(MD5_Digest d)
+{
+    memcpy(d, md_out, sizeof(QPDFCryptoImpl::MD5_Digest));
+}
+
+std::string
+QPDFCrypto_openssl::SHA2_digest()
+{
+    return std::string(reinterpret_cast<char*>(md_out), sha2_bits / 8);
+}
+
+void
+QPDFCrypto_openssl::RC4_init(unsigned char const* key_data, int key_len)
+{
+    check_openssl(EVP_CIPHER_CTX_reset(cipher_ctx));
+    if (key_len == -1)
+    {
+        key_len = QIntC::to_int(
+            strlen(reinterpret_cast<const char*>(key_data)));
+    }
+    check_openssl(
+        EVP_EncryptInit_ex(cipher_ctx, EVP_rc4(), nullptr, nullptr, nullptr));
+    check_openssl(EVP_CIPHER_CTX_set_key_length(cipher_ctx, key_len));
+    check_openssl(
+        EVP_EncryptInit_ex(cipher_ctx, nullptr, nullptr, key_data, nullptr));
+}
+
+void
+QPDFCrypto_openssl::rijndael_init(
+    bool encrypt, unsigned char const* key_data, size_t key_len,
+    bool cbc_mode, unsigned char* cbc_block)
+{
+    const EVP_CIPHER* cipher = nullptr;
+    switch (key_len)
+    {
+      case 32:
+        cipher = cbc_mode ? EVP_aes_256_cbc() : EVP_aes_256_ecb();
+        break;
+      case 24:
+        cipher = cbc_mode ? EVP_aes_192_cbc() : EVP_aes_192_ecb();
+        break;
+      default:
+        cipher = cbc_mode ? EVP_aes_128_cbc() : EVP_aes_128_ecb();
+        break;
+    }
+
+    check_openssl(EVP_CIPHER_CTX_reset(cipher_ctx));
+    check_openssl(
+        EVP_CipherInit_ex(cipher_ctx, cipher, nullptr,
+                          key_data, cbc_block, encrypt));
+    check_openssl(EVP_CIPHER_CTX_set_padding(cipher_ctx, 0));
+}
+
+void
+QPDFCrypto_openssl::RC4_process(
+    unsigned char* in_data, size_t len, unsigned char* out_data)
+{
+    if (nullptr == out_data)
+    {
+        out_data = in_data;
+    }
+    int out_len = static_cast<int>(len);
+    check_openssl(
+        EVP_EncryptUpdate(cipher_ctx, out_data, &out_len, in_data, out_len));
+}
+
+void
+QPDFCrypto_openssl::rijndael_process(
+    unsigned char* in_data, unsigned char* out_data)
+{
+    int len = QPDFCryptoImpl::rijndael_buf_size;
+    check_openssl(EVP_CipherUpdate(cipher_ctx, out_data, &len, in_data, len));
+}
+
+void
+QPDFCrypto_openssl::RC4_finalize()
+{
+    if (EVP_CIPHER_CTX_cipher(cipher_ctx))
+    {
+        check_openssl(EVP_CIPHER_CTX_reset(cipher_ctx));
+    }
+}
+
+void
+QPDFCrypto_openssl::rijndael_finalize()
+{
+    if (EVP_CIPHER_CTX_cipher(cipher_ctx))
+    {
+        check_openssl(EVP_CIPHER_CTX_reset(cipher_ctx));
+    }
+}