X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=net.c;h=ab6a98940b1e920eee7ee5e3f8f6b9bb33cf94b9;hp=7207e528f8c1dd781858d88d8d1761782494c99f;hb=0b36e0a77fc750af85e969efda7bda0931f389d0;hpb=09b7971c7a862924d4ce669f8a33bda567ba570b

diff --git a/net.c b/net.c
index 7207e528..ab6a9894 100644
--- a/net.c
+++ b/net.c
@@ -92,6 +92,47 @@ void disable_crypt(int fd)
 	crypt_data_array[fd].private_data = NULL;
 }
 
+/**
+ * Parse and validate IPv4 address/netmask string.
+ *
+ * \param cidr	  Address in CIDR notation
+ * \param addr	  Copy of the IPv4 address part of \a cidr
+ * \param addrlen Size of \a addr in bytes
+ * \param netmask Value of the netmask part in \a cidr or the
+ *		  default of 32 if not specified.
+ *
+ * \return Pointer to \a addr if succesful, NULL on error.
+ * \sa RFC 4632
+ */
+char *parse_cidr(const char *cidr,
+		 char	 *addr, ssize_t addrlen,
+		 int32_t *netmask)
+{
+	const char *o = cidr;
+	char *c = addr, *end = c + (addrlen - 1);
+
+	*netmask = 0x20;
+
+	if (cidr == NULL || addrlen < 1)
+		goto failed;
+
+	for (o = cidr; (*c = *o == '/'? '\0' : *o); c++, o++)
+		if (c == end)
+			goto failed;
+
+	if (*o == '/')
+		if (para_atoi32(++o, netmask) < 0 ||
+		    *netmask < 0 || *netmask > 0x20)
+			goto failed;
+
+	if (is_valid_ipv4_address(addr))
+		return addr;
+failed:
+	*addr = '\0';
+	return NULL;
+}
+
+
 /**
  * Match string as a candidate IPv4 address.
  *