pf-handler: Fix build with musl C library

musl's headers define a lot of networking structs.  For some, the
definition in the Linux UAPI headers is then suppressed by e.g.
__UAPI_DEF_ETHHDR.

Since we included musl's net/ethernet.h, which includes netinet/if_ether.h
that defines `struct ethhdr` (and the above constant), **after** we
include linux/if_ether.h, there was a compilation error because the
struct was defined multiple times.

However, simply moving that include doesn't fix the problem because for
ARP-specific structs the Linux headers don't provide __UAPI_DEF* checks.
So instead of directly including the linux/ headers, we include those
provided by the C library.  For glibc these usually just include the
Linux headers, but for musl this allows them to define the struct
directly.  We also need to move if.h and add packet.h, which define
other structs (or include headers that do so) that we use.

Fixes: 187c72d1afdc ("dhcp: Port the plugin to FreeBSD/macOS")

diff --git a/src/libcharon/network/pf_handler.c b/src/libcharon/network/pf_handler.c
index 91b0e7507f97acc732e83ca3b09dfbab56850761..43ef432ba607974b9ca6697da0b4de6a33d4d3e4 100644 (file)
--- a/src/libcharon/network/pf_handler.c
+++ b/src/libcharon/network/pf_handler.c
@@ -20,23 +20,23 @@
 
 #include <library.h>
 #include <unistd.h>
+#include <errno.h>
+#include <net/ethernet.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
 
 #if !defined(__APPLE__) && !defined(__FreeBSD__)
-#include <linux/if_arp.h>
-#include <linux/if_ether.h>
+#include <net/if_arp.h>
+#include <netinet/if_ether.h>
+#include <netpacket/packet.h>
 #include <linux/filter.h>
 #else
 #include <fcntl.h>
 #include <ifaddrs.h>
 #include <net/bpf.h>
-#include <net/if.h>
 #include <net/if_dl.h>
 #endif /* !defined(__APPLE__) && !defined(__FreeBSD__) */
 
-#include <errno.h>
-#include <net/ethernet.h>
-#include <sys/ioctl.h>
-
 #if !defined(__APPLE__) && !defined(__FreeBSD__)
 
 /**