Changeset 5699389 for lib

Timestamp:

03/05/13 13:43:48 (8 years ago)

Author:

Shane Alcock <salcock@…>

Branches:

4.0.1-hotfixes, cachetimestamps, develop, dpdk-ndag, etsilive, getfragoff, help, libtrace4, master, ndag_format, pfring, rc-4.0.1, rc-4.0.2, rc-4.0.3, rc-4.0.4, ringdecrementfix, ringperformance, ringtimestampfixes

Children:

af27241

Parents:

c5ff469

Message:

• Added new API functions for getting the source and destination IPs as strings. Dealing with sockaddrs is hard, especially for n00bs.

Location:

lib

Files:

• libtrace.h.in (modified) (2 diffs)
• protocols_l3.c (modified) (4 diffs)

lib/libtrace.h.in

@@ -2408 +2408 @@
                 struct sockaddr *addr);
 
+/** Get the source IP address for a packet and convert it into a string
+ * @param packet        The packet to extract the source IP address from
+ * @param space         A pointer to a character buffer to store the address 
+ *                      in. If NULL, static storage is used instead.
+ * @param spacelen      The size of the buffer passed in via 'space'. Set this
+ *                      to zero if you are going to pass in a NULL buffer.
+ * @return A pointer to a character buffer containing the string representation
+ * of the source IP address. For packets where there is no suitable IP address,
+ * the source MAC will be returned instead. Returns NULL if no valid address
+ * is available.
+ *
+ * @note Be wary of the possibility of the address being an IPv6 address - make
+ * sure your buffer is large enough!
+ *
+ * New in libtrace 3.0.17.
+ */
+DLLEXPORT SIMPLE_FUNCTION
+char *trace_get_source_address_string(const libtrace_packet_t *packet,
+                char *space, int spacelen);
+
 /** Get the destination IP address for a given packet
  * @param packet        The packet to extract the destination IP address from
@@ -2425 +2445 @@
                 struct sockaddr *addr);
 
+/** Get the destination IP address for a packet and convert it into a string
+ * @param packet        The packet to extract the destination IP address from
+ * @param space         A pointer to a character buffer to store the address 
+ *                      in. If NULL, static storage is used instead.
+ * @param spacelen      The size of the buffer passed in via 'space'. Set this
+ *                      to zero if you are going to pass in a NULL buffer.
+ * @return A pointer to a character buffer containing the string representation
+ * of the destination IP address. For packets where there is no suitable IP 
+ * address, the destination MAC will be returned instead. Returns NULL if no 
+ * valid address is available.
+ *
+ * @note Be wary of the possibility of the address being an IPv6 address - make
+ * sure your buffer is large enough!
+ *
+ * New in libtrace 3.0.17.
+ */
+DLLEXPORT SIMPLE_FUNCTION
+char *trace_get_destination_address_string(const libtrace_packet_t *packet,
+                char *space, int spacelen);
 
 /** Parses an IP or TCP option

lib/protocols_l3.c

@@ -38 +38 @@
 #include <assert.h>
 #include <stdlib.h>
+#include <arpa/inet.h>
 
 #ifdef HAVE_NETPACKET_PACKET_H
@@ -345 +346 @@
 }
 
+static char *sockaddr_to_string(struct sockaddr *addrptr, char *space,
+                int spacelen) {
+
+        assert(addrptr && space);
+        assert(spacelen > 0);
+        
+        if (addrptr->sa_family == AF_INET) {
+                struct sockaddr_in *v4 = (struct sockaddr_in *)addrptr;
+                inet_ntop(AF_INET, &(v4->sin_addr), space, spacelen);
+        }
+
+        else if (addrptr->sa_family == AF_INET6) {
+                struct sockaddr_in6 *v6 = (struct sockaddr_in6 *)addrptr;
+                inet_ntop(AF_INET6, &(v6->sin6_addr), space, spacelen);
+        }
+#ifdef HAVE_NETPACKET_PACKET_H
+        else if (addrptr->sa_family == AF_PACKET) {
+                struct sockaddr_ll *l2addr = (struct sockaddr_ll *)addrptr;
+                uint8_t *macbytes = (uint8_t *)l2addr->sll_addr;
+
+                snprintf(space, spacelen, "%02x:%02x:%02x:%02x:%02x:%02x",
+                                macbytes[0], macbytes[1], macbytes[2],
+                                macbytes[3], macbytes[4], macbytes[5]);
+
+        }
+#else
+        else if (addrptr->sa_family == AF_LINK) {
+                struct sockaddr_dl *l2addr = (struct sockaddr_dl *)addrptr;
+                uint8_t *macbytes = (uint8_t *)l2addr->sdl_data;
+
+                snprintf(space, spacelen, "%02x:%02x:%02x:%02x:%02x:%02x",
+                                macbytes[0], macbytes[1], macbytes[2],
+                                macbytes[3], macbytes[4], macbytes[5]);
+        
+        }
+#endif
+        else {
+                space[0] = '\0';
+                return NULL;
+        }
+
+        return space;
+
+}
+
 /* Extract the source mac address from a frame and bundle it up into a sockaddr */
 static struct sockaddr *get_source_ethernet_address(
@@ -469 +515 @@
 
 
+DLLEXPORT char *trace_get_source_address_string(
+                const libtrace_packet_t *packet, char *space, int spacelen) {
+
+        static char staticspace[INET6_ADDRSTRLEN];
+        struct sockaddr_storage addr;
+        struct sockaddr *addrptr;
+        
+
+        if (space == NULL || spacelen == 0) {
+                space = staticspace;
+                spacelen = INET6_ADDRSTRLEN;
+        }
+
+        addrptr = trace_get_source_address(packet, (struct sockaddr *)&addr);
+
+        if (addrptr == NULL)
+                return NULL;
+        
+        return sockaddr_to_string(addrptr, space, spacelen);
+}
+
 static struct sockaddr *get_destination_ethernet_address(
         libtrace_ether_t *ethernet, struct sockaddr *addr)
@@ -587 +654 @@
 }
 
-
+DLLEXPORT char *trace_get_destination_address_string(
+                const libtrace_packet_t *packet, char *space, int spacelen) {
+
+        struct sockaddr_storage addr;
+        struct sockaddr *addrptr;
+        
+        static char staticspace[INET6_ADDRSTRLEN];
+
+        if (space == NULL || spacelen == 0) {
+                space = staticspace;
+                spacelen = INET6_ADDRSTRLEN;
+        }
+
+        addrptr = trace_get_destination_address(packet, 
+                        (struct sockaddr *)&addr);
+
+        if (addrptr == NULL)
+                return NULL;
+        
+        return sockaddr_to_string(addrptr, space, spacelen);
+}
+