diff -r 5b9f20aa88c2 -r 9a4857d6444e libidav/utils.c
--- a/libidav/utils.c	Thu Mar 21 10:51:14 2019 +0100
+++ b/libidav/utils.c	Fri Mar 22 13:07:31 2019 +0100
@@ -224,6 +224,51 @@
     }
 }
 
+int util_szstrtouint(const char *str, uint64_t *value) {
+    char *end;
+    errno = 0;
+    size_t len = strlen(str);
+    uint64_t val = strtoull(str, &end, 0);
+    if(end == str+len) {
+        *value = val;
+        return 1;
+    } else if(end == str+len-1) {
+        uint64_t mul = 1;
+        switch(end[0]) {
+            case 'k':
+            case 'K': mul = 1024; break;
+            case 'm':
+            case 'M': mul = 1024*1024; break;
+            case 'g':
+            case 'G': mul = 1024*1024*1024; break;
+            default: return 0;
+        }
+        
+        uint64_t result = 0;
+        if(util_uint_mul(val, mul, &result)) {
+            return 0;
+        }
+        *value = result;
+        return 1;
+    }
+    return 0;
+}
+
+int util_uint_mul(uint64_t a, uint64_t b, uint64_t *result) {
+    if(a == 0 || b == 0) {
+        *result = 0;
+        return 0;
+    }
+    uint64_t r = a * b;
+    if(r / b == a) {
+        *result = r;
+        return 0;
+    } else {
+        *result = 0;
+        return 1;
+    }
+}
+
 char* util_url_base(char *url) {
     sstr_t u = sstr(url);
     int len = u.length;