Initial commit.HEADmaster

2 files changed, 77 insertions, 0 deletions

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..516c19d
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,6 @@
+CFLAGS ?= -O3 -march=native -fomit-frame-pointer -pipe
+
+knock-knock-token:
+.PHONY: clean
+clean:
+	rm -f knock-knock-token
diff --git a/knock-knock-token.c b/knock-knock-token.c
new file mode 100644
index 0000000..617202f
--- /dev/null
+++ b/knock-knock-token.c
@@ -0,0 +1,71 @@
+/*
+ * Knock-Knock Token
+ * by zx2c4
+ * Jason@zx2c4.com
+ *
+ * Someone about to steal your laptop and you have sensitive things open on it?
+ * With Knock-Knock Token, you specify a block device that belongs to removable
+ * storage such as a USB flash drive. When the flash drive is removed from the
+ * USB port, and the block device disappears as a consequence, your computer
+ * immediately turns off. So, as the thief is snatching your laptop from you,
+ * simply snatch the USB key, and your data is saved. The program automatically
+ * daemonizes.
+ *
+ * $ sudo ./knock-knock-token /dev/sdc1
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/inotify.h>
+#include <sys/reboot.h>
+
+int main(int argc, char *argv[])
+{
+	int inotify, device_monitor;
+	struct stat file_info;
+
+	if (argc < 2) {
+		fprintf(stderr, "Usage: %s BLOCK_DEVICE\n", argv[0]);
+		return EXIT_FAILURE;
+	}
+
+	if (getuid()) {
+		fprintf(stderr, "You must be root to run this program.\n");
+		return EXIT_FAILURE;
+	}
+
+	if (stat(argv[1], &file_info) < 0) {
+		perror("stat");
+		return EXIT_FAILURE;
+	}
+	if (!S_ISBLK(file_info.st_mode))
+		fprintf(stderr, "Warning: %s is not a block device. Are you sure you meant to monitor it?\n", argv[1]);
+
+	inotify = inotify_init();
+	if (inotify < 0) {
+		perror("inotify_init");
+		return EXIT_FAILURE;
+	}
+	device_monitor = inotify_add_watch(inotify, argv[1], IN_DELETE_SELF);
+	if (device_monitor < 0) {
+		perror("inotify_add_watch");
+		return EXIT_FAILURE;
+	}
+
+	fprintf(stderr, "Daemonizing...\n");
+	if (daemon(0, 0) < 0)
+		perror("daemon");
+
+	device_monitor = read(inotify, NULL, 0);
+
+	//TODO: securely wipe memory
+
+	sync();
+	reboot(RB_ENABLE_CAD);
+	reboot(RB_POWER_OFF);
+	reboot(RB_HALT_SYSTEM);
+	
+	return EXIT_SUCCESS;
+}