kvs: add working AP firmware version detection

Makefile

@@ -1,4 +1,4 @@
-CC ?= gcc
+CC := gcc
 SHELL ?= /bin/sh
 KVSFLIST := \
 	src/KVS/main.c \

include/hex_utils.h

@@ -1,3 +1,6 @@
+#include <stdbool.h>
+#include <stdint.h>
+
 uint32_t convert_to_uint32(const char *str) {
     char *endptr;
     unsigned long ul_value = strtoul(str, &endptr, 0);

include/sysinfo.h

@@ -0,0 +1,29 @@
+void trim_newline(char* str) {
+    size_t len = strlen(str);
+    if (len > 0 && str[len - 1] == '\n') {
+        str[len - 1] = '\0';
+    }
+}
+
+
+const char* getFirmwareVersion(){
+    // note, may not work on all chromebooks
+    FILE *fptr;
+    char stupidfile[] = "/sys/class/dmi/id/bios_version";
+    fptr = fopen(stupidfile, "r");
+    static char firmwareVersion[1024];
+
+    if (fptr == NULL) {
+        printf("Error reading Firmware Version \n");
+        printf("Please report as a bug at https://github.com/kxtzownsu/KVS-private\n");
+        
+        sleep(86400); // sleep for 1d if error
+        return "Error!"; 
+    }
+    fgets(firmwareVersion, 100, fptr); 
+    fclose(fptr);
+
+    trim_newline(firmwareVersion);
+
+    return firmwareVersion;
+}

src/KVS/main.c

@@ -1,11 +1,18 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 #include "ui.h"
+#include "sysinfo.h"
 
 int main(int argc, char **argv) {
+	if (geteuid() !=  0){
+		printf("Please run KVS as root!\n");
+		exit(1);
+	}
+
 	// example values for testing
-	char* fwver = "Google_Grunt.11031.149.0";
+	const char* fwver = getFirmwareVersion();
 	char* kernver = "0x00010001";
 	char* tpmver = "2.0";
 	char* fwmp = "0x1";