X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=net.c;h=b3588f6d9e3d43d62f592a982b11f0db5f1e550b;hp=f10afb71e31f0a1e7178972102b22c0feb01bfcc;hb=732bf143e456df7fc2e845884fbbdfdaf3fafebc;hpb=a18295788a381a5083e42fde7d7615b328bb6509

diff --git a/net.c b/net.c
index f10afb71..b3588f6d 100644
--- a/net.c
+++ b/net.c
@@ -36,6 +36,47 @@
 #include "string.h"
 #include "fd.h"
 
+/**
+ * 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.
  *