Use libnl to add/remove IPs on Linux

diff --git a/Makefile b/Makefile
index 9ac4356ecc4c9e805615a6f1ff2e1cca411783bd..79b1fbe914ac237ce13671127f6f0d23b20f3984 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -5,6 +5,11 @@ LIBS = -lpcap
 CFLAGS += -Wall -g -DNMRPFLASH_VERSION=\"$(VERSION)\"
 LDFLAGS += $(LIBS)
 
+ifeq ($(shell uname -s),Linux)
+       CFLAGS += $(shell pkg-config libnl-route-3.0 --cflags)
+       LIBS += $(shell pkg-config libnl-route-3.0 --libs)
+endif
+
 nmrpflash_OBJ = nmrp.o tftp.o ethsock.o main.o util.o
 
 .PHONY: clean install release release/osx release/linux release/win32

diff --git a/ethsock.c b/ethsock.c
index 18774e0df090e8d5c84c52711ced909209dd2c9a..e1d8a4541837c345ccea3f40cc5f6240dc2f11f6 100644 (file)
--- a/ethsock.c
+++ b/ethsock.c
@@ -38,6 +38,7 @@
 #if defined(NMRPFLASH_LINUX)
 #define NMRPFLASH_AF_PACKET AF_PACKET
 #include <linux/if_packet.h>
+#include <netlink/route/addr.h>
 #else
 #define NMRPFLASH_AF_PACKET AF_LINK
 #include <net/if_types.h>
@@ -156,6 +157,62 @@ static bool bridge_stp(const char *intf, bool enabled)
 
        return ret;
 }
+
+static bool xrtnl_addr_set(struct rtnl_addr *ra, uint32_t addr, int (*cb)(struct rtnl_addr*, struct nl_addr*))
+{
+       struct nl_addr *na = nl_addr_build(AF_INET, &addr, 4);
+       if (!na) {
+               xperror("nl_addr_build");
+               return false;
+       }
+
+       cb(ra, na);
+       nl_addr_put(na);
+
+       return true;
+}
+
+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 (!(ra = rtnl_addr_alloc())) {
+               xperror("rtnl_addr_alloc");
+               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 ((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));
+       }
+
+out:
+       nl_addr_put(na);
+       rtnl_addr_put(ra);
+       nl_socket_free(sk);
+
+       return !err;
+}
 #endif
 
 static bool intf_get_info(const char *intf, uint8_t *hwaddr, bool *bridge)
@@ -779,7 +836,7 @@ static inline void set_addr(void *p, uint32_t addr)
 #endif
 }
 
-#ifndef NMRPFLASH_WINDOWS
+#if !defined(NMRPFLASH_WINDOWS) && !defined(NMRPFLASH_LINUX)
 static bool intf_up(int fd, const char *intf, bool up)
 {
        struct ifreq ifr;
@@ -809,47 +866,34 @@ static bool intf_up(int fd, const char *intf, bool up)
 }
 #endif
 
-int ethsock_ip_add(struct ethsock *sock, uint32_t ipaddr, uint32_t ipmask, struct ethsock_ip_undo **undo)
+static int ethsock_ip_add_del(struct ethsock *sock, uint32_t ipaddr, uint32_t ipmask, struct ethsock_ip_undo **undo, bool add)
 {
-       if (undo && !(*undo = malloc(sizeof(struct ethsock_ip_undo)))) {
-               xperror("malloc");
-               return -1;
+       int ret, fd;
+
+       if (add && undo) {
+               if (!(*undo = malloc(sizeof(struct ethsock_ip_undo)))) {
+                       xperror("malloc");
+                       return -1;
+               }
+
+               memset(*undo, 0, sizeof(**undo));
        }
 
-       int ret = -1;
-       int fd = socket(AF_INET, SOCK_DGRAM, 0);
+       ret = -1;
+       fd = socket(AF_INET, SOCK_DGRAM, 0);
        if (fd < 0) {
                sock_perror("socket");
                goto out;
        }
 
 #ifndef NMRPFLASH_WINDOWS
-       // XXX: undo is non-zero only if we're adding an IP
-       bool add = undo;
 #ifdef NMRPFLASH_LINUX
-       struct ifreq ifr;
-       strncpy(ifr.ifr_name, sock->intf, IFNAMSIZ);
-       // FIXME: automatically determine the next free alias
-       strcat(ifr.ifr_name, ":42");
-
        if (add) {
-               set_addr(&ifr.ifr_addr, ipaddr);
-               if (ioctl(fd, SIOCSIFADDR, &ifr) != 0) {
-                       xperror("ioctl(SIOSIFADDR)");
-                       goto out;
-               }
-
-               set_addr(&ifr.ifr_netmask, ipmask);
-               if (ioctl(fd, SIOCSIFNETMASK, &ifr) != 0) {
-                       xperror("ioctl(SIOCSIFNETMASK)");
-                       goto out;
-               }
-
                (*undo)->ip[0] = ipaddr;
                (*undo)->ip[1] = ipmask;
        }
 
-       if (!intf_up(fd, ifr.ifr_name, add)) {
+       if (!intf_add_del_ip(sock->intf, (*undo)->ip[0], (*undo)->ip[1], add)) {
                goto out;
        }
 #else // NMRPFLASH_OSX (or any other BSD)
@@ -917,6 +961,11 @@ out:
        return ret;
 }
 
+int ethsock_ip_add(struct ethsock *sock, uint32_t ipaddr, uint32_t ipmask, struct ethsock_ip_undo **undo)
+{
+       return ethsock_ip_add_del(sock, ipaddr, ipmask, undo, true);
+}
+
 int ethsock_ip_del(struct ethsock *sock, struct ethsock_ip_undo **undo)
 {
        if (!*undo) {
@@ -927,7 +976,7 @@ int ethsock_ip_del(struct ethsock *sock, struct ethsock_ip_undo **undo)
 
 #ifndef NMRPFLASH_WINDOWS
        if ((*undo)->ip[0] != INADDR_NONE) {
-               ret = ethsock_ip_add(sock, (*undo)->ip[0], (*undo)->ip[1], NULL);
+               ret = ethsock_ip_add_del(sock, (*undo)->ip[0], (*undo)->ip[1], undo, false);
        } else {
                ret = 0;
        }