Encryption (and compression as plugins) support.

[dump.git] / common / transformation.h

diff --git a/common/transformation.h b/common/transformation.h
new file mode 100644 (file)
index 0000000..5e667fa
--- /dev/null
+++ b/common/transformation.h
@@ -0,0 +1,144 @@
+#include <config.h>
+#include <bsdcompat.h>
+#include <protocols/dumprestore.h>
+
+#ifndef __P
+#include <sys/cdefs.h>
+#endif
+
+#ifdef HAVE_LZO
+#include <minilzo.h>
+#endif /* HAVE_LZO */
+
+#ifdef HAVE_OPENSSL
+#include <openssl/evp.h>
+#include <openssl/rand.h>
+#include <openssl/pkcs12.h>
+#endif
+
+#ifndef _transformation_H
+#define _transformation_H
+
+/*
+ * Compression/encryption hooks.
+ *
+ * Open questions:
+ * 1. should it be a failure if compress/decompress is called and we DON'T have the code included?
+ */
+
+typedef struct transformation {
+       int enc;
+       union {
+#ifdef HAVE_LZO
+               struct {
+                       lzo_align_t __LZO_MMODEL *LZO_WorkMem;
+               } lzo;
+#endif /* HAVE_LZO */
+#ifdef HAVE_ZLIB
+               struct {
+                       int complvl;
+               } zlib;
+#endif /* HAVE_ZLIB */
+#ifdef HAVE_BZLIB
+               struct {
+                       int complvl;
+               } bzlib;
+#endif /* HAVE_ZLIB */
+#ifdef HAVE_OPENSSL
+               struct {
+                       int complvl;
+
+                       // encryption/decryption key
+                       unsigned char key[EVP_MAX_KEY_LENGTH];
+                       unsigned int keylen;
+
+                       // crypto
+                       const EVP_CIPHER *cipher;
+                       const EVP_MD *digest;
+                       ENGINE *engine;
+
+                       // this assumes we're multi-process but not multi-threaded
+                       EVP_CIPHER_CTX *dataCtx;
+                       EVP_CIPHER_CTX *ivCtx;
+               } ssl;
+#endif
+       } state;
+
+       /*
+        * The name of the compression/encryption algorithm, for
+        * display purposes.
+        */
+       const char *name;
+
+       /*
+        * Is this mandatory even if the size of the buffer increases?
+        * As a general rule compression is optional * and encryption is
+        * mandatory.
+        */
+       int mandatory;
+
+       /*
+        * Initialize the system.
+        * (mode: 1 = compress/encrypt, 0 = decompress/decrypt)
+        */
+       int (*initialize) __P((struct transformation *xform, int mode));
+
+       /*
+        * Shut down the system
+        */
+       int (*shutdown) __P((struct transformation *xform));
+
+       /*
+        * Do anything necessary after forking the process.
+        */
+       int (*startNewTape) __P((struct transformation *xform,
+               struct tapebuf *tpbin, unsigned long *destlen));
+
+       /*
+        * The dump process is master-slave with the actual
+        * disk and dump tape access handled by the slave processes.
+        * This method performs any initialization required by
+        * the latter process. (E.g., some encryption libraries
+        * must be reinitialized.)
+        */
+       int (*startDiskIOProcess) __P((struct transformation *xform));
+
+       /*
+        * Clean up everything before the slave process ends.
+        */
+       int (*endDiskIOProcess) __P((struct transformation *xform));
+
+       /*
+        * Compress/encrypt buffer.
+        */
+       int (*compress) __P((struct transformation *xform, struct tapebuf *, unsigned long *destlen,
+                       const char *src, int srclen));
+
+       /*
+        * Decompress/decrypt buffer.
+        */
+       int (*decompress) __P((struct transformation *xform, struct tapebuf *, unsigned long *destlen,
+                       const char *src, int srclen, char **reason));
+
+} Transformation;
+
+extern Transformation transformation_null;
+
+#ifdef HAVE_LZO
+extern Transformation *transformation_lzo_factory(int enc);
+#endif /* HAVE_ZLIB */
+
+#ifdef HAVE_ZLIB
+extern Transformation *transformation_zlib_factory(int enc, int complvl);
+#endif /* HAVE_ZLIB */
+
+#ifdef HAVE_BZLIB
+extern Transformation *transformation_bzlib_factory(int enc, int complvl);
+#endif /* HAVE_BZLIB */
+
+#ifdef HAVE_OPENSSL
+extern Transformation *transformation_ssl_factory(int enc, int complvl,
+               const char *ciphername, const char *digestname);
+#endif /* HAVE_OPENSSL */
+
+#endif /* _transformation_H */