Implement ethsock_arp_* on other platforms

Fixes #4.

diff --git a/ethsock.c b/ethsock.c
index e1d8a4541837c345ccea3f40cc5f6240dc2f11f6..6c4defda08e9e6652f708dd1d3c0934a52734110 100644 (file)
--- a/ethsock.c
+++ b/ethsock.c
@@ -19,6 +19,7 @@
 
 #include <sys/types.h>
 #include <stdbool.h>
+#include <stdarg.h>
 #include <string.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -39,6 +40,7 @@
 #define NMRPFLASH_AF_PACKET AF_PACKET
 #include <linux/if_packet.h>
 #include <netlink/route/addr.h>
+#include <netlink/route/neighbour.h>
 #else
 #define NMRPFLASH_AF_PACKET AF_LINK
 #include <net/if_types.h>
@@ -97,6 +99,24 @@ static int x_pcap_findalldevs(pcap_if_t **devs)
        return 0;
 }
 
+static int systemf(const char *fmt, ...)
+{
+       char cmd[1024];
+       int ret;
+       va_list va;
+       va_start(va, fmt);
+
+       ret = vsnprintf(cmd, sizeof(cmd) - 1, fmt, va);
+       if (ret >= sizeof(cmd) - 1) {
+               return -1;
+       }
+
+       ret = system(cmd);
+       va_end(va);
+
+       return ret;
+}
+
 #ifndef NMRPFLASH_WINDOWS
 static inline bool sockaddr_get_hwaddr(struct sockaddr *sa, uint8_t *hwaddr)
 {
@@ -160,33 +180,47 @@ static bool bridge_stp(const char *intf, bool enabled)
 
 static bool xrtnl_addr_set(struct rtnl_addr *ra, uint32_t addr, int (*cb)(struct rtnl_addr*, struct nl_addr*))
 {
+       int err;
        struct nl_addr *na = nl_addr_build(AF_INET, &addr, 4);
+
        if (!na) {
                xperror("nl_addr_build");
                return false;
        }
 
-       cb(ra, na);
+       if ((err = cb(ra, na)) != 0 && verbosity) {
+               nl_perror(err, __func__);
+       }
        nl_addr_put(na);
 
        return true;
 }
 
+static struct nl_sock *xnl_socket_route()
+{
+       int err;
+       struct nl_sock *sk = nl_socket_alloc();
+       if (sk) {
+               if (!(err = nl_connect(sk, NETLINK_ROUTE))) {
+                       return sk;
+               }
+               nl_socket_free(sk);
+               nl_perror(err, "nl_connect");
+       } else {
+               xperror("nl_socket_alloc");
+       }
+
+       return NULL;
+}
+
 static bool intf_add_del_ip(const char *intf, uint32_t ipaddr, uint32_t ipmask, bool add)
 {
        struct rtnl_addr *ra = NULL;
-       struct nl_addr *na = NULL;
        struct nl_sock *sk = NULL;
        int err = 1;
 
-       if (!(sk = nl_socket_alloc())) {
-               xperror("nl_socket_alloc");
-               goto out;
-       }
-
-       if ((err = nl_connect(sk, NETLINK_ROUTE)) < 0) {
-               fprintf(stderr, "nl_connect: %s\n", nl_geterror(err));
-               goto out;
+       if (!(sk = xnl_socket_route())) {
+               return false;
        }
 
        if (!(ra = rtnl_addr_alloc())) {
@@ -194,25 +228,85 @@ static bool intf_add_del_ip(const char *intf, uint32_t ipaddr, uint32_t ipmask,
                goto out;
        }
 
-       if (!xrtnl_addr_set(ra, (ipaddr & ipmask) | ~ipmask, &rtnl_addr_set_broadcast)
-               || !xrtnl_addr_set(ra, ipaddr, &rtnl_addr_set_local)) {
-               return false;
-       }
-
        rtnl_addr_set_ifindex(ra, if_nametoindex(intf));
        rtnl_addr_set_prefixlen(ra, bitcount(ipmask));
 
+       if (!xrtnl_addr_set(ra, (ipaddr & ipmask) | ~ipmask, &rtnl_addr_set_broadcast)
+                       || !xrtnl_addr_set(ra, ipaddr, &rtnl_addr_set_local)) {
+               goto out;
+       }
+
        if ((err = add ? rtnl_addr_add(sk, ra, 0) : rtnl_addr_delete(sk, ra, 0)) < 0) {
-               fprintf(stderr, "%s: %s\n", add ? "rtnl_addr_add" : "rtnl_addr_delete", nl_geterror(err));
+               if (add && err == -NLE_EXIST) {
+                       err = 0;
+               } else if (add || verbosity > 1) {
+                       nl_perror(err, add ? "rtnl_addr_add" : "rtnl_addr_delete");
+               }
        }
 
 out:
-       nl_addr_put(na);
        rtnl_addr_put(ra);
        nl_socket_free(sk);
 
        return !err;
 }
+
+static bool intf_add_del_arp(const char *intf, uint32_t ipaddr, uint8_t *hwaddr, bool add)
+{
+       struct nl_sock *sk;
+       struct rtnl_neigh *neigh;
+       struct nl_addr *mac, *ip;
+       int err = 1;
+
+       sk = NULL;
+       neigh = NULL;
+       mac = ip = NULL;
+
+       if (!(sk = xnl_socket_route())) {
+               goto out;
+       }
+
+       if (!(neigh = rtnl_neigh_alloc())) {
+               xperror("rtnl_neigh_alloc");
+               goto out;
+       }
+
+       if (!(mac = nl_addr_build(AF_PACKET, hwaddr, 6))) {
+               xperror("nl_addr_build");
+               goto out;
+       }
+
+       if (!(ip = nl_addr_build(AF_INET, &ipaddr, 4))) {
+               xperror("nl_addr_build");
+               goto out;
+       }
+
+       rtnl_neigh_set_ifindex(neigh, if_nametoindex(intf));
+       rtnl_neigh_set_dst(neigh, ip);
+
+       err = rtnl_neigh_delete(sk, neigh, 0);
+
+       if (add) {
+               rtnl_neigh_set_lladdr(neigh, mac);
+               rtnl_neigh_set_state(neigh, NUD_PERMANENT);
+               system("arp -an");
+               err = rtnl_neigh_add(sk, neigh, NLM_F_CREATE);
+               system("arp -an");
+       }
+
+       if (err && (add || verbosity > 1)) {
+               nl_perror(err, add ? "rtnl_neigh_add" : "rtnl_neigh_delete");
+       }
+
+out:
+       nl_addr_put(ip);
+       nl_addr_put(mac);
+       rtnl_neigh_put(neigh);
+       nl_socket_free(sk);
+
+       return !err;
+}
+
 #endif
 
 static bool intf_get_info(const char *intf, uint8_t *hwaddr, bool *bridge)
@@ -620,20 +714,12 @@ inline int ethsock_set_timeout(struct ethsock *sock, unsigned msec)
        return 0;
 }
 
-#ifndef NMRPFLASH_WINDOWS
-int ethsock_arp_add(struct ethsock *sock, uint8_t *hwaddr, uint32_t ipaddr, struct ethsock_arp_undo **undo)
-{
-       return 0;
-}
-
-int ethsock_arp_del(struct ethsock *sock, struct ethsock_arp_undo **undo)
-{
-       return 0;
-}
-#else
 static int ethsock_arp(struct ethsock *sock, uint8_t *hwaddr, uint32_t ipaddr, struct ethsock_arp_undo **undo)
 {
-       DWORD ret;
+#if defined(NMRPFLASH_UNIX) && !defined(NMRPFLASH_LINUX)
+       struct in_addr addr = { .s_addr = ipaddr };
+#elif defined(NMRPFLASH_WINDOWS)
+       DWORD err;
        MIB_IPNETROW arp = {
                .dwIndex = sock->index,
                .dwPhysAddrLen = 6,
@@ -642,13 +728,24 @@ static int ethsock_arp(struct ethsock *sock, uint8_t *hwaddr, uint32_t ipaddr, s
        };
 
        memcpy(arp.bPhysAddr, hwaddr, 6);
+#endif
 
        if (undo) {
-               ret = CreateIpNetEntry(&arp);
-               if (ret != NO_ERROR) {
-                       win_perror2("CreateIpNetEntry", ret);
+#if defined(NMRPFLASH_LINUX)
+               if (!intf_add_del_arp(sock->intf, ipaddr, hwaddr, true)) {
+                       return -1;
+               }
+#elif defined(NMRPFLASH_WINDOWS)
+               err = CreateIpNetEntry(&arp);
+               if (err != NO_ERROR) {
+                       win_perror2("CreateIpNetEntry", err);
+                       return -1;
+               }
+#else
+               if (systemf("arp -s %s %s", inet_ntoa(addr), mac_to_str(hwaddr)) != 0) {
                        return -1;
                }
+#endif
 
                *undo = malloc(sizeof(struct ethsock_arp_undo));
                if (!*undo) {
@@ -659,7 +756,15 @@ static int ethsock_arp(struct ethsock *sock, uint8_t *hwaddr, uint32_t ipaddr, s
                (*undo)->ipaddr = ipaddr;
                memcpy((*undo)->hwaddr, hwaddr, 6);
        } else {
-               DeleteIpNetEntry(&arp);
+#if defined(NMRPFLASH_LINUX)
+               if (!intf_add_del_arp(sock->intf, ipaddr, hwaddr, false)) {
+                       return -1;
+               }
+#elif defined(NMRPFLASH_WINDOWS)
+               return DeleteIpNetEntry(&arp) ? 0 : -1;
+#else
+               return systemf("arp -d %s", inet_ntoa(addr);
+#endif
        }
 
        return 0;
@@ -682,7 +787,6 @@ int ethsock_arp_del(struct ethsock *sock, struct ethsock_arp_undo **undo)
        *undo = NULL;
        return ret;
 }
-#endif
 
 static bool get_hwaddr_from_pcap(const pcap_if_t *dev, uint8_t *hwaddr)
 {
@@ -981,8 +1085,7 @@ int ethsock_ip_del(struct ethsock *sock, struct ethsock_ip_undo **undo)
                ret = 0;
        }
 #else
-       DeleteIPAddress((*undo)->context);
-       ret = 0;
+       ret = DeleteIPAddress((*undo)->context) ? 0 : -1;
 #endif
 
        free(*undo);