diff --git a/contrib/base64/base64rev-gen.c b/contrib/base64/base64rev-gen.c
new file mode 100644
index 0000000..faffc87
--- /dev/null
+++ b/contrib/base64/base64rev-gen.c
@@ -0,0 +1,70 @@
+/*
+ * base64rev generator
+ *
+ * Copyright 2009-2010 Krzysztof Piotr Oledzki <ole@ans.pl>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <stdio.h>
+
+const char base64tab[65]="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+char base64rev[128];
+
+#define base '#'	/* arbitrary chosen base value */
+#define B64MAX	64
+#define B64PADV B64MAX
+
+int main() {
+	char *p, c;
+	int i, min = 255, max = 0;
+
+	for (i = 0; i < sizeof(base64rev); i++)
+		base64rev[i] = base;
+
+	for (i = 0;  i < B64MAX; i++) {
+		c = base64tab[i];
+
+		if (min > c)
+			min = c;
+
+		if (max < c)
+			max = c;
+	}
+
+	for (i = 0;  i < B64MAX; i++) {
+		c = base64tab[i];
+
+		if (base+i+1 > 127) {
+			printf("Wrong base value @%d\n", i);
+			return 1;
+		}
+
+		base64rev[c - min] = base+i+1;
+	}
+
+	base64rev['=' - min] = base + B64PADV;
+
+	base64rev[max - min + 1] = '\0';
+
+	printf("#define B64BASE '%c'\n", base);
+	printf("#define B64CMIN '%c'\n", min);
+	printf("#define B64CMAX '%c'\n", max);
+	printf("#define B64PADV %u\n", B64PADV);
+
+	p = base64rev;
+	printf("const char base64rev[]=\"");
+	for (p = base64rev; *p; p++) {
+		if (*p == '\\')
+			printf("\\%c", *p);
+		else
+			printf("%c", *p);
+	}
+	printf("\"\n");
+
+	return 0;
+}