summaryrefslogtreecommitdiff
path: root/src/encryption.c
blob: c3f77ce4d71898f3032172e99db4cfc0b32d832c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
/**
 * @file encryption.c
 * @author syxhe (https://t.me/syxhe)
 * @brief A collection of all encryption related functions
 * @version 0.1
 * @date 2025-06-09
 *
 * @copyright Copyright (c) 2025
 *
 */

// TODO: Go back and make sure every function has proper error handling
// Oh fucking christ what have I done
// I need to make sure every single function in this file returns with an indicated error instead of nuking the whole program with
//  error()

#define _GNU_SOURCE 1

#ifndef __VXGG_REWRITE___ENCRYPTION_C___1481879318188___
#define __VXGG_REWRITE___ENCRYPTION_C___1481879318188___

#define TPSIZE (1<<13)

#include "shared.c"
#include "threadpool.c"

#include <sodium.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <dirent.h>
#include <stdarg.h>
#include <unistd.h>

#include <stdio.h>
#include <string.h>

#include <errno.h>
#include <error.h>

/// 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
#define ___VXGG___ALWAYS_CHECK_LIBSODIUM___ 1

/// Grants access to the `vxgg_setsodiumfailcb` function, which can be used to set a custom callback for what to do when libsodium
/// fails upon initialization
#define ___VXGG___USE_CLS_CALLBACK___ 1

/// Chunk size for en/decryption. 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
//! A list of possible words for password creation
#define PASSWORD_WORDS (\
    (const char * const []){\
        "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", \
        "others", "without", "justice", "peace", "power", "seas", "war", "do", "declaration", "america", "becomes", "necessary", \
        "political", "equal", "declare", "causes", "separation", "men", "happiness", "any", "form", "alter", "or", "will", \
        "forms", "same", "object", "off", "necessity", "history", "great", "britain", "tyranny", "over", "public", "good", \
        "unless", "suspended", "so", "would", "legislature", "only", "legislative", "bodies", "purpose", "into", "dissolved", \
        "state", "endeavoured", "refusing", "hither", "conditions", "establishing", "offices", "out", "armies", "legislatures", \
        "render", "jurisdiction", "foreign", "acts", "pretended", "trial", "inhabitants", "cases", "transporting", "rule", \
        "declaring", "here", "protection", "against", "lives", "circumstances", "ages", "totally", "friends", "brethren", "whose", \
        "every", "may", "therefore", "ought", "unanimous", "thirteen", "course", "human", "events", "one", "dissolve", "bands", \
        "connected", "another", "assume", "earth", "separate", "station", "nature", "natures", "god", "entitle", "decent", \
        "respect", "opinions", "requires", "impel", "truths", "self", "evident", "created", "endowed", "creator", "certain", \
        "unalienable", "life", "liberty", "pursuit", "secure", "instituted", "deriving", "just", "governed", "whenever", \
        "destructive", "ends", "abolish", "institute", "laying", "foundation", "principles", "organizing", "shall", "seem", \
        "likely", "effect", "safety", "prudence", "indeed", "dictate", "established", "not", "changed", "light", "transient", \
        "accordingly", "experience", "hath", "shewn", "more", "disposed", "suffer", "while", "evils", "sufferable", "than", \
        "accustomed", "but", "train", "abuses", "pursuing", "invariably", "evinces", "design", "reduce", "under", "despotism", \
        "duty", "throw", "provide", "guards", "future", "security", "patient", "sufferance", "now", "constrains", "former", \
        "systems", "present", "king", "injuries", "having", "direct", "establishment", "prove", "let", "facts", "submitted", \
        "candid", "wholesome", "forbidden", "governors", "immediate", "pressing", "importance", "operation", "till", "obtained", \
        "utterly", "neglected", "attend", "accommodation", "districts", "those", "relinquish", "representation", "inestimable", \
        "formidable", "tyrants", "called", "together", "places", "unusual", "uncomfortable", "distant", "depository", "records", \
        "sole", "fatiguing", "compliance", "measures", "representative", "houses", "repeatedly", "opposing", "manly", "firmness", \
        "invasions", "after", "dissolutions", "cause", "elected", "whereby", "incapable", "annihilation", "returned", "exercise", \
        "remaining", "mean", "exposed", "dangers", "invasion", "convulsions", "within", "prevent", "population", "obstructing", \
        "naturalization", "foreigners", "encourage", "migrations", "raising", "appropriations", "lands", "obstructed", \
        "administration", "judiciary", "made", "judges", "dependent", "alone", "tenure", "amount", "payment", "salaries", \
        "erected", "multitude", "sent", "swarms", "officers", "harrass", "eat", "substance", "kept", "times", "standing", \
        "affected", "military", "superior", "civil", "combined", "subject", "constitution", "unacknowledged", "giving", \
        "legislation", "quartering", "armed", "troops", "protecting", "mock", "punishment", "murders", "commit", "cutting", \
        "trade", "parts", "imposing", "taxes", "depriving", "many", "benefits", "jury", "beyond", "tried", "offences", "system", \
        "english", "neighbouring", "province", "therein", "arbitrary", "enlarging", "boundaries", "once", "example", "fit", \
        "instrument", "introducing", "taking", "away", "charters", "valuable", "altering", "fundamentally", "suspending", "own", \
        "invested", "legislate", "whatsoever", "abdicated", "waging", "plundered", "ravaged", "coasts", "burnt", "towns", \
        "destroyed", "mercenaries", "compleat", "works", "death", "desolation", "already", "begun", "cruelty", "perfidy", \
        "scarcely", "paralleled", "barbarous", "unworthy", "head", "civilized", "nation", "constrained", "fellow", "citizens", \
        "taken", "captive", "high", "bear", "arms", "country", "become", "executioners", "fall", "hands", "excited", "domestic", \
        "insurrections", "amongst", "bring", "frontiers", "merciless", "indian", "savages", "known", "warfare", "undistinguished", \
        "destruction", "sexes", "stage", "oppressions", "petitioned", "redress", "humble", "terms", "petitions", "answered", \
        "injury", "prince", "character", "thus", "marked", "act", "define", "tyrant", "unfit", "ruler", "nor", "wanting", \
        "attentions", "brittish", "warned", "attempts", "extend", "unwarrantable", "reminded", "emigration", "settlement", \
        "appealed", "native", "magnanimity", "conjured", "ties", "common", "kindred", "disavow", "inevitably", "interrupt", \
        "connections", "correspondence", "too", "deaf", "voice", "consanguinity", "must", "acquiesce", "denounces", "rest", \
        "enemies", "representatives", "general", "congress", "assembled", "appealing", "supreme", "judge", "rectitude", \
        "intentions", "name", "authority", "solemnly", "publish", "absolved", "allegiance", "british", "crown", "connection", \
        "between", "full", "levy", "conclude", "contract", "alliances", "establish", "commerce", "things", "support", "firm", \
        "reliance", "divine", "providence", "mutually", "pledge", "each", "fortunes", "sacred", "honor"\
    }\
)
//! Short macro for getting the `PASSWORD_WORDS` array size
#define PASSWORD_WORDS_LEN (STATIC_ARRAY_LEN(PASSWORD_WORDS))

#if ___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0
#if ___VXGG___USE_CLS_CALLBACK___ > 0

//! Definition for the callback function that fires when a call to checksodium fails
typedef void (*vxgg_naclfailcb)(void*);

/**
 * @brief Default sodium init fail callback for use in `checksodiumcb()`
 *
 * @param none Unused param to fit callback spec
 */
static void naclfaildefault(void *none) {
    none = none; // Makes gcc happy
    if(___VXGG___VERBOSE_ERRORS___)
        error(1, ENOTSUP, "<naclfaildefault> Couldn't initialize sodium for some reason. Quitting...");
    exit(EXIT_FAILURE);
}

/**
 * @brief Internal function to deal with the `___VXGG___USE_CLS_CALLBACK___` macro
 *
 * `checksodiumcb()` runs the sodium function `sodium_init()` and on error calls the provided callback with the provided data. The
 * callback and data default to `naclfaildefault` and `NULL`, but can be changed when the `set` parameter is non-zero. When `set`
 * is zero, the sodium init check is preformed
 *
 * @note `checksodiumcb()` is ran when these conditions are true - 1: The `___VXGG___ALWAYS_CHECK_LIBSODIUM___` and `___VXGG___USE_CLS_CALLBACK___`
 * macros are both greater than 0 when compiling, and 2: a function in `encryption.c` calls a function originating from sodium. This
 * function exists as a way to deal with sodium failing yourself, instead of instantly calling `exit()`. If you don't care to handle
 * it, or are initializing sodium yourself, this is unnecessary
 *
 * @param callback A callback to be ran when sodium fails to initialize itself. Ignored if `set` is zero. Must be non-null when `set` is non-zero
 * @param data Data to be passed to the callback when it is fired. Ignored if `set` is zero. May be null
 * @param set Flag on whether to check sodium or to set a new callback and data pair. Checks sodium when zero, sets callback & data when non-zero
 * @retval int
 */
static int checksodiumcb(vxgg_naclfailcb const callback, void *data, unsigned char set) {
    static vxgg_naclfailcb cb = naclfaildefault;
    static void *usr = NULL;
    int ret;

    if(set) {
        if(cb == NULL) ERRRET(EINVAL, -1);
        cb = callback;
        usr = data;
        return 2;   // libsodium normally returns 1 if the library is already initialized, so this is to signal that the callback has been updated
    }

    if((ret = sodium_init()) < 0) {
        if(cb == NULL)
            error(0, EINVAL, "<checksodiumcb> refusing to run a null callback");
        else
            cb(usr);
    }

    return ret;
}

void vxgg_setsodiumfailcb(vxgg_naclfailcb cb, void *data) {
    checksodiumcb(cb, data, 1);
}

#endif

/**
 * @brief Simple function to check if sodium has been properly initialized
 *
 * `checksodium()` will run in functions located in `encryption.h` only when the macro `___VXGG___ALWAYS_CHECK_LIBSODIUM___` is greater
 * than zero when compiling. It will call the `checksodiumcb()` function if compiled with the `___VXGG___USE_CLS_CALLBACK___` macro.
 * When called, checksodium will run `sodium_init()`, and will either run the user-defined callback or `XALLOC_EXIT`.
 *
 */
static void checksodium(void) {
    #if ___VXGG___USE_CLS_CALLBACK___ > 0
    checksodiumcb(NULL, NULL, 0);
    #else

    if(sodium_init() < 0) {
        errno = ENOTSUP;
        XALLOC_EXIT("<checksodium> Couldn't initialize sodium for some reason. Quitting...");
    }

    #endif

    return;
}

#endif

/**
 * @brief open() with the flags O_TMPFILE, O_WRONLY, O_CLOEXEC, and O_SYNC. Opened with mode S_IRUSR, S_IWUSR
 *
 * @param dest The filename the new descriptor should have. Must be non-null
 * @retval (int)[-1,int] A new file descriptor. -1 on error
 */
int maketmp(const char * const dest) {
    if(!dest) ERRRET(EINVAL, -1);
    return open(dest, (O_TMPFILE | O_WRONLY | O_CLOEXEC | O_SYNC), (S_IRUSR | S_IWUSR));
}

/**
 * @brief Link a file descriptor into the filesystem
 *
 * @param target New filename the descriptor should have
 * @param tgfd The file descriptor to link
 * @retval (int)[-1, 0] 0 on success, -1 on error
 */
int linkto(const char * const target, int tgfd) {
    if(!target) ERRRET(EINVAL, -1);

    char *path = NULL;
    asprintf(&path, "/proc/self/fd/%d", tgfd);
    if(!path)
        ERROR(1, errno, "<linkto> Couldn't get path to move file into system",);
    remove(target); // Make sure an old version isn't sticking around (it's not catastrophic if this fails, but it should be noted or logged somewhere)
    // TODO: This is bad. If a file gets deleted and the program crashes before the new one can get linked into the fs, the data is lost.
    // I really should write a function entirely dedicated to dealing with linking

    int res = linkat(AT_FDCWD, path, AT_FDCWD, target, AT_SYMLINK_FOLLOW);
    free(path);
    return res;
}


static void __ucl_close(void *fd) {
    if(!fd) return;
    close(*(int*)fd);
    *(int*)fd = -1;
    return;
}

static void __ucl_fclose(void *file) {
    if(!file) return;
    fclose((FILE*)file);
    return;
}

/**
 * @brief Encrypt src to dst using libsodium's xchacha encryption suite
 *
 * @param src File to encrypt
 * @param dst Destination to write encrypted file
 * @param key Key for encryption
 * @retval (int)[-1, 0] Returns 0 on success, sets errno and returns -1 on error
 */
int encrypttofile(FILE *src, FILE *dst, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]) {
    if(!src || !dst || !key) ERRRET(EINVAL, -1);
    #if ___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0
        checksodium();
    #endif

    unsigned char  buf[CHUNKSIZE], cbuf[CHUNKSIZE + crypto_secretstream_xchacha20poly1305_ABYTES];
    unsigned char  header[crypto_secretstream_xchacha20poly1305_HEADERBYTES];
    crypto_secretstream_xchacha20poly1305_state state;
    unsigned long long cbuflen;
    unsigned char tag;
    size_t bytesread;
    int eof;

    // Write the header
    crypto_secretstream_xchacha20poly1305_init_push(&state, header, key);
    if(fwrite(header, 1, sizeof(header), dst) < sizeof(header)) {
        if(ferror(dst)) {
            WARN(errno, "<encrypttofile> Could not write header",);
            return -1;
        }
    }

    // Encrypt each chunk
    do {
        if((bytesread = fread(buf, 1, sizeof(buf), src)) < sizeof(buf))
            if(ferror(src)) {
                WARN(errno, "<encrypttofile> Could not read from source",);
                return -1;
            }
        eof = feof(src);
        tag = eof ? crypto_secretstream_xchacha20poly1305_TAG_FINAL : 0;

        crypto_secretstream_xchacha20poly1305_push(&state, cbuf, &cbuflen, buf, bytesread, NULL, 0, tag);
        if(fwrite(cbuf, 1, (size_t)cbuflen, dst) < (size_t)cbuflen)
            if(ferror(dst)) {
                WARN(errno, "<encrypttofile> Could not write to target",);
                return -1;
            }
    } while (!eof);

    return 0;
}

/**
 * @brief Decrypt src to dst using libsodium's xchacha encryption suite
 *
 * @param src File to decrypt
 * @param dst Destination to write decrypted file
 * @param key Key used to encrypt
 * @retval (int)[-1, 0] Returns 0 on success, sets errno and returns -1 on error
 */
int decrypttofile(FILE *src, FILE *dst, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]) {
    if(!src || !dst || !key) ERRRET(EINVAL, -1);
    #if ___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0
        checksodium();
    #endif

    unsigned char  cbuf[CHUNKSIZE + crypto_secretstream_xchacha20poly1305_ABYTES], buf[CHUNKSIZE];
    unsigned char  header[crypto_secretstream_xchacha20poly1305_HEADERBYTES];
    crypto_secretstream_xchacha20poly1305_state state;
    unsigned long long buflen;
    unsigned char  tag;
    size_t bytesread;
    int eof;

    // Read the header
    if(fread(header, 1, sizeof(header), src) < sizeof(header)) {
        if(ferror(src)) {
            WARN(errno, "<decrypttofile> Couldn't read header", );
            return -1;
        }
    }

    // Make sure the header isn't fuckey
    if(crypto_secretstream_xchacha20poly1305_init_pull(&state, header, key) != 0) {
        WARN(errno, "<decrypttofile> Incomplete header", );
        return -1;
    }

    // Decrypt each chunk
    do {
        if((bytesread = fread(cbuf, 1, sizeof(cbuf), src)) < sizeof(cbuf)) {
            if(ferror(src)) {
                WARN(errno, "<decrypttofile> Ran into problem reading for decryption", );
                return -1;
            }
        }
        eof = feof(src);

        if (crypto_secretstream_xchacha20poly1305_pull(&state, buf, &buflen, &tag, cbuf, bytesread, NULL, 0) != 0) {
            WARN(errno, "<decrypttofile> Corrupted chunk", );
            return -1;
        }

        if(tag == crypto_secretstream_xchacha20poly1305_TAG_FINAL && !eof) {
            WARN(errno, "<decrypttofile> End of stream before end of file", );
            return -1;
        }
        if(eof && tag != crypto_secretstream_xchacha20poly1305_TAG_FINAL) {
            WARN(errno, "<decrypttofile> End of file before end of stream", );
            return -1;
        }

        fwrite(buf, 1, (size_t)buflen, dst);
    } while(! eof);

    return 0;
}

/**
 * @brief Encrypt file at `target` to `output` using Linux's named temp file system to do it in the background
 *
 * @param target
 * @param output
 * @param key
 * @retval (int)[,]
 */
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

    cleanup_CREATE(10);
    int fd = -1, tfd = -1;
    FILE *src, *dst;
    char *targetdir;

    // Open the target file
    if((fd = open(target, O_RDONLY)) < 0)
        return -1;
    cleanup_REGISTER(__ucl_close, (void*)&fd);

    // Create a temp file for writing
    targetdir = vxdirname(output);
    if(!targetdir)
        cleanup_MARK();
    cleanup_CNDREGISTER(free, targetdir);

    // Actually get the file descriptor for the temp file
    cleanup_CNDEXEC(
        tfd = maketmp(targetdir);
        if(tfd < 0)
            cleanup_MARK();
        cleanup_CNDREGISTER(__ucl_close, (void*)&tfd);
    );

    // Create a FILE* version of the source fd
    cleanup_CNDEXEC(
        if(!(src = fdopen(fd, "rb"))) {
            WARN(errno, "<encryptviatmp> Couldn't open \"%s\"", , target);
            cleanup_MARK();
        }
        cleanup_CNDREGISTER(__ucl_fclose, (void*)&src);
    )

    // Create a FILE* version of the target fd
    cleanup_CNDEXEC(
        if(!(dst = fdopen(tfd, "wb"))) {
            WARN(errno, "<encryptviatmp> Couldn't open \"%s\"", , output);
            cleanup_MARK();
        }
        cleanup_CNDREGISTER(__ucl_fclose, (void*)dst);
    );


    // Do the encryption now that everything has been set up
    cleanup_CNDEXEC(
        // Not going to bother changing this, it probably is catastrophic if an error happens when it shouldn't
        if(encrypttofile(src, dst, key) < 0)
            ERROR(1, ENOTRECOVERABLE, "<encryptviatmp> I don't even have a way to cause an error here. How did you do it?",);

        // Link the temp file into the system
        if(linkto(output, tfd) < 0)
            WARN(errno, "<encryptviatmp> Could not link \"%s\" into system after encryption", , output);

        free(targetdir);
        fclose(dst);
        fclose(src);
        // fclose alco closes fd and tfd, as fdopen does not dup the file descriptors
    );


    cleanup_CNDFIRE();
    if(cleanup_ERRORFLAGGED)
        return -1;

    return 0;
}

/**
 * @brief Decrypt the file at `encrypted` to `target`
 *
 * @param encrypted
 * @param target
 * @param key
 * @retval (int)[,]
 */
int decryptto(const char * const target, const char * const output, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]) {
    if(!target || !output || !key) ERRRET(EINVAL, -1);
    #if ___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0
        checksodium();
    #endif

    cleanup_CREATE(10);
    FILE *src, *dst;
    int fdst;

    // Open the source file
    if(!(src = fopen(target, "rb"))) {
        WARN(errno, "<decryptto> Could not open \"%s\" for decryption", , target);
        return -1;
    }
    cleanup_REGISTER(__ucl_fclose, src);

    // Get a temp descriptor for the temp file
    cleanup_CNDEXEC(
        fdst = maketmp(output);
        if(!fdst) {
            WARN(errno, "<decryptto> Could not get temp file for decryption", );
            cleanup_MARK();
        }
        cleanup_CNDREGISTER(__ucl_close, (void*)&fdst);
    );

    // Open a FILE* version of the temp file
    cleanup_CNDEXEC(
        if(!(dst = fdopen(fdst, "wb"))) {
            WARN(errno, "<decryptto> Could not open \"%s\" for writing decrypted data", , output);
            cleanup_MARK();
        }
        cleanup_CNDREGISTER(__ucl_fclose, dst);
    );

    // Follow through with the rest of the decryption
    cleanup_CNDEXEC(
        if(decrypttofile(src, dst, key) < 0)
            ERROR(1, errno, "<decryptto> How did you even cause an error?",);

        // Link temp into system
        if(linkto(output, fdst) < 0)
            WARN(errno, "<decryptto> Could not link \"%s\" into system", , output);

        fclose(dst);
        fclose(src);
        // fclose alco closes fd and tfd, as fdopen does not dup the file descriptors
    );

    cleanup_CNDFIRE();
    if(cleanup_ERRORFLAGGED)
        return -1;

    // Note: If an error were to theoretically occur, which shouldn't be possible but I'm covering my bases here, after the
    // `dst = fdopen` line, a double close on the temp file descriptor would occur. I've been told that this is not catastrophic,
    // and considering how my multithreading works it *should* be fine, but it very well could cause problems. The easy solution is
    // to man up and just write another cleanup function to pop the last thing off the stack, but again this is an error I can't
    // actually trigger so it's fine for now

    return 0;
}

/**
 * @brief Generate a password viable for use in the derivation of a key
 *
 * @param str Pointer to a string. This will be filled by a malloc'ed string of words (the password). Must be non-null
 * @param words The number of words to include in the password. A password of at least 20 words and probably not more than 40 is recommended
 * @retval (int)[-1, words] On success, returns the number of words requested. On error, returns -1 and sets errno
 */
int genpassword(char **str, unsigned int words) {
    // Early returns
    if(words < 1) return 0;
    if(!str) ERRRET(EINVAL, -1);
    #if ___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0
        checksodium();
    #endif

    // Bootstrap the first word
    char *lstr = NULL, *tmp = NULL;
    if(asprintf(&lstr, "%s", PASSWORD_WORDS[randombytes_uniform(PASSWORD_WORDS_LEN)]) < 0)
        return -1;

    // Concat the rest of the words into the password (without leaking memory)
    int ret;
    for(unsigned int i = 1; i < words; i++) {
        ret = asprintf(&tmp, "%s %s", lstr, PASSWORD_WORDS[randombytes_uniform(PASSWORD_WORDS_LEN)]);
        sodium_memzero(lstr, strlen(lstr) + 1);
        free(lstr);
        if(ret < 0)
            return -1;

        lstr = tmp;
    }

    *str = lstr;
    return words;
}

/**
 * @brief sodium_malloc wrapper.
 *
 * Calls `error()` or `abort()` depnding on the value of `___VXGG___XALLOC_EXIT_ON_ERROR___`. Will make sure libsodium is initialized if `___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0`
 *
 * @param size
 * @retval (void*) A pointer to some data allocated via `sodium_malloc()`
 */
void* xsodium_malloc(size_t size) {
    #if ___VXGG___ALWAYS_CHECK_LIBSODIUM___ > 0
        checksodium();
    #endif

    void *mem = sodium_malloc(size);
    if(mem == NULL)
        XALLOC_EXIT("<xsodium_malloc> could not allocate memory... Quitting", );

    return mem;
}



// TODO: Rewrite this to use the threadpool. Each newly scanned file should be pushed onto the threadpool as an encryption task

// #include <dirent.h>

// dlinkedlist * scandirlist(const char * const dir, int (*selector)(const struct dirent *), int (*cmp)(const struct dirent **, const struct dirent **)) {
//     if(!dir || selector == NULL || cmp == NULL) ERRRET(EINVAL, NULL);

//     struct dirent **namelist = NULL;
//     dlinkedlist *list = NULL;
//     int numentries = -1;

//     if((numentries = scandir(dir, &namelist, selector, cmp)) < 0)
//         ERRRET(errno, NULL);

//     list = dlinkedlist_init();
//     for(int i = 0; i < numentries; i++)
//         if(dlinkedlist_append(list, (void *)(namelist[i]), free) < 0) {
//             dlinkedlist_free(list);
//             for(int j = i; j < numentries; j++)
//                 free(namelist[j]);

//             free(namelist);
//             ERRRET(errno, NULL);
//         }
//     free(namelist);

//     return list;
// }

// Above implementation is flawed and would not actually scan the entire system. The process must be recursive:
    // Step 1 - Create directory list
    // Step 2 - Create --cryption ctq
    // Step 3 - Scan initial starting dir. This will be /home/
    // Step 4 - Iterate over scan results
        // Step 4.1 - For all directory dirent objects, add them to the directory list
        // Step 4.2 - For all file dirent objects, add them to the --cryption ctq
    // Step 5 - Scan next entry in the dirlist, removing it once done. Repeat Step 4
    // Step 6 - Free dirlist once empty, return newly populated --cryption ctq

// Idea: Create 2 ctqs. Use one for the actual scanning, and the other as the return result. That way, not only will scanning be
// fast, but I can also just reuse code I've already written and not make some absolute spaghetti mess trying to do everything
// linearly

int __cscan_worker(void *data) {
    if(!data) return -1;

    return 0;
}

ctqueue * cryptscan() {
    ctqueue *res = ctqueue_init(TPSIZE), *working = ctqueue_init(TPSIZE);
    if(!res || !working) ERRRET(errno, NULL);

    task *start = task_init(__cscan_worker, free, NULL);
    if(!start) ERRRET(errno, NULL);
    ctqueue_waitpush(working, start);


    return res;
}

#endif