Create decryptto function

2 files changed, 39 insertions, 13 deletions

diff --git a/src/encryption.c b/src/encryption.c
index 606be03..c176d6e 100644
--- a/src/encryption.c
+++ b/src/encryption.c
@@ -29,7 +29,7 @@ int checksodiumcb(const vxgg_naclfailcb callback, void *data, unsigned char set)
     static vxgg_naclfailcb cb = naclfaildefault;
     static void *usr = NULL;
     int ret;
-    
+
     if(set) {
         cb = callback;
         usr = data;
@@ -73,7 +73,7 @@ int maketmp(const char * const dest) {
     return open(dest, (O_TMPFILE | O_WRONLY | O_CLOEXEC | O_SYNC), (S_IRUSR | S_IWUSR));
 }
 
-int encrypttotmp(const char * const target, const char * const output, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]) {
+int encryptviatmp(const char * const target, const char * const output, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]) {
     #if ___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0
     checksodium();
     #endif
@@ -106,7 +106,6 @@ int encrypttotmp(const char * const target, const char * const output, const uns
     asprintf(&path, "/proc/self/fd/%d", tfd);
     if(!path)
         return -1;
-
     remove(output); // Make sure an old version isn't sticking around
     linkat(AT_FDCWD, path, AT_FDCWD, output, AT_SYMLINK_FOLLOW);
 
@@ -118,6 +117,33 @@ int encrypttotmp(const char * const target, const char * const output, const uns
     return 0;
 }
 
+int decryptto(const char * const encrypted, const char * const target, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]) {
+    #if ___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0
+        checksodium();
+    #endif
+
+    if(!encrypted)
+        RETURNWERR(EINVAL, -1);
+    if(!target)
+        RETURNWERR(EINVAL, -1);
+    if(!key)
+        RETURNWERR(EINVAL, -1);
+
+    FILE *src, *dst;
+    if(!(src = fopen(encrypted, "rb")))
+        ERROR(1, errno, "Could not open \"%s\" for decryption", , encrypted);
+    if(!(dst = fopen(target, "wb")))
+        ERROR(1, errno, "Could not open \"%s\" for writing decrypted data", , target);
+    
+    if(decrypttofile(src, dst, key) < 0)
+        ERROR(1, errno, "How did you even cause an error?",);
+
+    fclose(dst);
+    fclose(src);
+
+    return 0;
+}
+
 int encrypttofile(FILE *dst, FILE *src, unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]) {
     unsigned char  buf[CHUNKSIZE], cbuf[CHUNKSIZE + crypto_secretstream_xchacha20poly1305_ABYTES];
     unsigned char  header[crypto_secretstream_xchacha20poly1305_HEADERBYTES];
diff --git a/src/encryption.h b/src/encryption.h
index 1f04dae..b5fe04e 100644
--- a/src/encryption.h
+++ b/src/encryption.h
@@ -3,9 +3,6 @@
 
 #include <sodium.h>
 
-#define CHUNKSIZE (1 << 9)
-
-
 // Determines whether any function that calls libsodium functions also checks to make sure libsodium is actually initialized. May
 // cause unexpected issues with early exiting due to libsodium failing to initialize properly. It's recommended that you just
 // manually run `sodium_init()` in some main or init function of your own so that you can deal with a potential error yourself
@@ -16,10 +13,7 @@
 #define ___VXGG___USE_CLS_CALLBACK___ 1
 
 
-
-
 #if ___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0
-
 // Checks if sodium is initialized. Initializes it if not. If `___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0`, it's possible to set an error callback to avoid exiting the entire program. Otherwise calls `error()` if libsodium can't initialize
 void checksodium(void);
 
@@ -30,14 +24,17 @@ typedef void (*vxgg_naclfailcb)(void*);
 // Sets the error callback for when libsodium fails. Runs `cb(data)` if `(sodium_init() < 0)`
 void vxgg_setsodiumfailcb(const vxgg_naclfailcb cb, void *data);
 #endif
-
 #endif
 
+// Chunk size for en/de-cryption. I originally wanted to use st_blksize from stat(), but given that those chunks may be of different
+// sizes between computers / filesystems / architectures / files, it's easier to just have this be a consistent macro
+#define CHUNKSIZE (1 << 9)
+
 // Fuck reading from a file. Even if someone ran strings on the binary and got this they wouldn't be able to regenerate the key
 #define PASSWORD_WORDS (\
     (const char *[]){\
-        "the", "of", "to", "and", "for", "our", "their", "has", "in", "he", "a", "them", "that", "these", "by", "have", "we", "us",\
-        "people", "which", "all", "is", "with", "laws", "be", "are", "his", "states", "on", "they", "right", "it", "from", \
+        "the", "of", "to", "and", "for", "our", "their", "has", "in", "he", "a", "them", "that", "these", "by", "have", "we", \
+        "us", "people", "which", "all", "is", "with", "laws", "be", "are", "his", "states", "on", "they", "right", "it", "from", \
         "government", "such", "among", "powers", "most", "an", "time", "should", "new", "as", "been", "colonies", "assent", \
         "large", "at", "independent", "free", "united", "when", "mankind", "hold", "rights", "governments", "consent", "its", \
         "long", "themselves", "abolishing", "usurpations", "absolute", "repeated", "this", "world", "refused", "pass", "other", \
@@ -96,6 +93,9 @@ int maketmp(const char * const dest);
 int encrypttofile(FILE *dst, FILE *src, unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]);
 int decrypttofile(FILE *dst, FILE *src, unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]);
 
-int encrypttotmp(const char * const target, const char * const output, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]);
+int encryptviatmp(const char * const target, const char * const output, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]);
+int decryptto(const char * const encrypted, const char * const target, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]);
+
+int genpassword(char **str, unsigned int words);
 
 #endif
\ No newline at end of file