cmd-attachments.c

/*
 * Copyright (c) 2018 Tim van der Molen <tim@kariliq.nl>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "config.h"

#include <sys/stat.h>

#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "sigbak.h"

enum type {
	ATTACHMENT,
	AVATAR,
	STICKER
};

static int
write_file(struct sbk_ctx *ctx, Signal__BackupFrame *frm,
    struct sbk_file *file, enum type type)
{
	FILE	*fp;
	char	*fname, *tmp;
	int	 ret;

	tmp = NULL;

	switch (type) {
	case ATTACHMENT:
		if (frm->attachment == NULL)
			return 0;
		if (!frm->attachment->has_rowid ||
		    !frm->attachment->has_attachmentid) {
			warnx("Invalid attachment frame");
			return 1;
		}
		if (asprintf(&tmp, "%" PRIu64 "-%" PRIu64,
		    frm->attachment->rowid, frm->attachment->attachmentid)
		    == -1) {
			warnx("asprintf() failed");
			return 1;
		}
		fname = tmp;
		break;
	case AVATAR:
		if (frm->avatar == NULL)
			return 0;
		if (frm->avatar->recipientid != NULL)
			fname = frm->avatar->recipientid;
		else if (frm->avatar->name != NULL)
			fname = frm->avatar->name;
		else {
			warnx("Invalid avatar frame");
			return 1;
		}
		if (fname[0] == '\0' || strchr(fname, '/') != NULL) {
			warnx("Invalid avatar filename");
			return 1;
		}
		break;
	case STICKER:
		if (frm->sticker == NULL)
			return 0;
		if (!frm->sticker->has_rowid) {
			warnx("Invalid sticker frame");
			return 1;
		}
		if (asprintf(&tmp, "%" PRIu64, frm->sticker->rowid) == -1) {
			warnx("asprintf() failed");
			return 1;
		}
		fname = tmp;
		break;
	default:
		return 0;
	}

	ret = 0;

	if ((fp = fopen(fname, "wx")) == NULL) {
		warn("%s", fname);
		ret = 1;
	} else {
		if (sbk_write_file(ctx, file, fp) == -1) {
			warnx("%s: %s", fname, sbk_error(ctx));
			ret = 1;
		}
		fclose(fp);
	}

	freezero_string(tmp);
	return ret;
}

static int
write_files(int argc, char **argv, enum type type)
{
	struct sbk_ctx		*ctx;
	struct sbk_file		*file;
	Signal__BackupFrame	*frm;
	char			*cmd, *passfile, passphr[128];
	const char		*outdir;
	int			 c, ret;

	cmd = argv[0];
	passfile = NULL;

	while ((c = getopt(argc, argv, "p:")) != -1)
		switch (c) {
		case 'p':
			passfile = optarg;
			break;
		default:
			goto usage;
		}

	argc -= optind;
	argv += optind;

	switch (argc) {
	case 1:
		outdir = ".";
		break;
	case 2:
		outdir = argv[1];
		if (mkdir(outdir, 0777) == -1 && errno != EEXIST)
			err(1, "mkdir: %s", outdir);
		break;
	default:
		goto usage;
	}

	if (unveil(argv[0], "r") == -1 || unveil(outdir, "rwc") == -1)
		err(1, "unveil");

	if (passfile == NULL) {
		if (pledge("stdio rpath wpath cpath tty", NULL) == -1)
			err(1, "pledge");
	} else {
		if (unveil(passfile, "r") == -1)
			err(1, "unveil");

		if (pledge("stdio rpath wpath cpath", NULL) == -1)
			err(1, "pledge");
	}

	if ((ctx = sbk_ctx_new()) == NULL)
		errx(1, "Cannot create backup context");

	if (get_passphrase(passfile, passphr, sizeof passphr) == -1) {
		sbk_ctx_free(ctx);
		return 1;
	}

	if (sbk_open(ctx, argv[0], passphr) == -1) {
		warnx("%s: %s", argv[0], sbk_error(ctx));
		explicit_bzero(passphr, sizeof passphr);
		sbk_ctx_free(ctx);
		return 1;
	}

	explicit_bzero(passphr, sizeof passphr);

	if (chdir(outdir) == -1) {
		warn("chdir: %s", outdir);
		sbk_close(ctx);
		sbk_ctx_free(ctx);
		return 1;
	}

	if (pledge("stdio wpath cpath", NULL) == -1)
		err(1, "pledge");

	ret = 0;

	while ((frm = sbk_get_frame(ctx, &file)) != NULL) {
		ret |= write_file(ctx, frm, file, type);
		sbk_free_frame(frm);
		sbk_free_file(file);
	}

	if (!sbk_eof(ctx)) {
		warnx("%s: %s", argv[0], sbk_error(ctx));
		ret = 1;
	}

	sbk_close(ctx);
	sbk_ctx_free(ctx);
	return ret;

usage:
	usage(cmd, "[-p passfile] backup [directory]");
}

int
cmd_attachments(int argc, char **argv)
{
	return write_files(argc, argv, ATTACHMENT);
}

int
cmd_avatars(int argc, char **argv)
{
	return write_files(argc, argv, AVATAR);
}

int
cmd_stickers(int argc, char **argv)
{
	return write_files(argc, argv, STICKER);
}