We add a helper function to calculate the default IPv4 prefix length
based on address class. This is used to replace the current inline
calculation in conf_ip4(), and is also a preparation for more uses
of this functionality in the coming commits.
Signed-off-by: Jon Maloy
---
conf.c | 15 +++------------
ip.c | 21 +++++++++++++++++++++
ip.h | 2 ++
3 files changed, 26 insertions(+), 12 deletions(-)
diff --git a/conf.c b/conf.c
index 0e96f36..31acc20 100644
--- a/conf.c
+++ b/conf.c
@@ -733,18 +733,9 @@ static unsigned int conf_ip4(unsigned int ifi, struct ip4_ctx *ip4,
}
/* Apply default prefix_len to first address if not set */
- if (!ip4->addrs[0].prefix_len) {
- in_addr_t a = ntohl(ip4->addrs[0].addr.s_addr);
-
- if (IN_CLASSA(a))
- ip4->addrs[0].prefix_len = 8;
- else if (IN_CLASSB(a))
- ip4->addrs[0].prefix_len = 16;
- else if (IN_CLASSC(a))
- ip4->addrs[0].prefix_len = 24;
- else
- ip4->addrs[0].prefix_len = 32;
- }
+ if (!ip4->addrs[0].prefix_len)
+ ip4->addrs[0].prefix_len =
+ ip4_default_prefix_len(&ip4->addrs[0].addr);
ip4->addr_seen = ip4->addrs[0].addr;
diff --git a/ip.c b/ip.c
index 9a7f4c5..2519c71 100644
--- a/ip.c
+++ b/ip.c
@@ -13,6 +13,8 @@
*/
#include
+#include
+
#include "util.h"
#include "ip.h"
@@ -67,3 +69,22 @@ found:
*proto = nh;
return true;
}
+
+/**
+ * ip4_default_prefix_len() - Get default prefix length for IPv4 address
+ * @addr: IPv4 address
+ *
+ * Return: prefix length based on address class (8/16/24), or 32 for other
+ */
+int ip4_default_prefix_len(const struct in_addr *addr)
+{
+ in_addr_t a = ntohl(addr->s_addr);
+
+ if (IN_CLASSA(a))
+ return 8;
+ if (IN_CLASSB(a))
+ return 16;
+ if (IN_CLASSC(a))
+ return 24;
+ return 32;
+}
diff --git a/ip.h b/ip.h
index 748cb1f..065b78b 100644
--- a/ip.h
+++ b/ip.h
@@ -139,6 +139,8 @@ static const struct in_addr in4addr_broadcast = { 0xffffffff };
#define IP4_MAX_ADDRS 8
#define IP6_MAX_ADDRS 16
+int ip4_default_prefix_len(const struct in_addr *addr);
+
/**
* struct ip4_addr_entry - IPv4 address with prefix length
* @addr: IPv4 address
--
2.51.1