Added ip_current_netif() & ip_current_header() to receive extended info about the currently received packet.

CHANGELOG

@@ -19,6 +19,10 @@ HISTORY
 
   ++ New features:
 
+  2009-05-05 Simon Goldschmidt, Jakob Stoklund Olesen
+  * ip.h, ip.c: Added ip_current_netif() & ip_current_header() to receive
+    extended info about the currently received packet.
+
   2009-04-27 Simon Goldschmidt
   * sys.h: Made SYS_LIGHTWEIGHT_PROT and sys_now() work with NO_SYS=1
 

src/core/ipv4/ip.c

@@ -56,6 +56,45 @@
 #include "lwip/stats.h"
 #include "arch/perf.h"
 
+/**
+ * The interface that provided the packet for the current callback
+ * invocation.
+ */
+static struct netif *current_netif;
+
+/**
+ * Header of the input packet currently being processed.
+ */
+static const struct ip_hdr *current_header;
+
+/**
+ * Get the interface that received the current packet.
+ *
+ * This function must only be called from a receive callback (udp_recv,
+ * raw_recv, tcp_accept). It will return NULL otherwise.
+ *
+ * @param pcb Pointer to the pcb receiving a packet.
+ */
+struct netif *
+ip_current_netif()
+{
+  return current_netif;
+}
+
+/**
+ * Get the IP header of the current packet.
+ *
+ * This function must only be called from a receive callback (udp_recv,
+ * raw_recv, tcp_accept). It will return NULL otherwise.
+ *
+ * @param pcb Pointer to the pcb receiving a packet.
+ */
+const struct ip_hdr *
+ip_current_header()
+{
+  return current_header;
+}
+
 /**
  * Finds the appropriate network interface for a given IP address. It
  * searches the list of network interfaces linearly. A match is found
@@ -388,6 +427,9 @@ ip_input(struct pbuf *p, struct netif *inp)
   ip_debug_print(p);
   LWIP_DEBUGF(IP_DEBUG, ("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len));
 
+  current_netif = inp;
+  current_header = iphdr;
+
 #if LWIP_RAW
   /* raw input did not eat the packet? */
   if (raw_input(p, inp) == 0)
@@ -440,6 +482,9 @@ ip_input(struct pbuf *p, struct netif *inp)
     }
   }
 
+  current_netif = NULL;
+  current_header = NULL;
+
   return ERR_OK;
 }
 

src/include/ipv4/lwip/ip.h

@@ -55,6 +55,8 @@ err_t ip_output_if(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
 err_t ip_output_hinted(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
        u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint);
 #endif /* LWIP_NETIF_HWADDRHINT */
+struct netif *ip_current_netif();
+const struct ip_hdr *ip_current_header();
 
 #define IP_HLEN 20
 

src/include/ipv6/lwip/ip.h

@@ -114,6 +114,9 @@ err_t ip_output_if(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
       u8_t ttl, u8_t proto,
       struct netif *netif);
 
+#define ip_current_netif() NULL
+#define ip_current_header() NULL
+
 #if IP_DEBUG
 void ip_debug_print(struct pbuf *p);
 #endif /* IP_DEBUG */