1 files changed, 49 insertions, 0 deletions
diff --git a/libs/libnet/ip.c b/libs/libnet/ip.c
new file mode 100644
index 0000000..20e1a38
--- /dev/null
+++ b/libs/libnet/ip.c
@@ -0,0 +1,49 @@
+// MIT License, Copyright (c) 2020 Marvin Borner
+// Most net/ip handlers are in the kernel space
+// This is a userspace wrapper for some things
+
+#include <def.h>
+#include <libnet/net.h>
+#include <mem.h>
+#include <str.h>
+
+// Inspired by Paul Vixie, 1996
+int ip_pton(const char *src, u32 *dst)
+{
+	const char *end = src + strlen(src);
+	u8 tmp[4], *tp;
+	int ch = 0;
+	int saw_digit = 0;
+	int octets = 0;
+	*(tp = tmp) = 0;
+
+	while (src < end) {
+		ch = *src++;
+		if (ch >= '0' && ch <= '9') {
+			u32 new = *tp * 10 + (ch - '0');
+
+			if ((saw_digit && *tp == 0) || new > 255)
+				return 0;
+
+			*tp = new;
+			if (!saw_digit) {
+				if (++octets > 4)
+					return 0;
+				saw_digit = 1;
+			}
+		} else if (ch == '.' && saw_digit) {
+			if (octets == 4)
+				return 0;
+			*++tp = 0;
+			saw_digit = 0;
+		} else {
+			return 0;
+		}
+	}
+
+	if (octets < 4)
+		return 0;
+
+	*dst = htonl(*(u32 *)tmp);
+	return 1;
+}