diff options
| -rw-r--r-- | networking/arping.c | 39 |
1 files changed, 20 insertions, 19 deletions
diff --git a/networking/arping.c b/networking/arping.c index 59092a7..788fded 100644 --- a/networking/arping.c +++ b/networking/arping.c @@ -28,6 +28,7 @@ //usage: "\n -A ARP answer mode, update your neighbors" //usage: "\n -c N Stop after sending N ARP requests" //usage: "\n -w TIMEOUT Seconds to wait for ARP reply" +//NB: in iputils-s20160308, iface is mandatory, no default //usage: "\n -I IFACE Interface to use (default eth0)" //usage: "\n -s SRC_IP Sender IP address" //usage: "\n DST_IP Target IP address" @@ -56,8 +57,8 @@ enum { #define GETOPT32(str_timeout, device, source) \ getopt32(argv, "^" \ "UDAqfbc:+w:I:s:" \ - /* Dad also sets quit_on_reply, */ \ - /* Advert also sets unsolicited: */ \ + /* DAD also sets quit_on_reply, */ \ + /* advert also sets unsolicited: */ \ "\0" "=1:Df:AU", \ &count, &str_timeout, &device, &source \ ); @@ -67,7 +68,6 @@ struct globals { struct in_addr dst; struct sockaddr_ll me; struct sockaddr_ll he; - int sock_fd; int count; // = -1; unsigned last; @@ -80,7 +80,9 @@ struct globals { unsigned brd_recv; unsigned req_recv; + /* should be in main(), but are here to reduce stack use: */ struct ifreq ifr; + struct sockaddr_in probe_saddr; sigset_t sset; unsigned char packet[4096]; } FIX_ALIASING; @@ -88,7 +90,6 @@ struct globals { #define dst (G.dst ) #define me (G.me ) #define he (G.he ) -#define sock_fd (G.sock_fd ) #define count (G.count ) #define last (G.last ) #define timeout_us (G.timeout_us) @@ -106,6 +107,8 @@ struct globals { count = -1; \ } while (0) +#define sock_fd 3 + static int send_pack(struct in_addr *src_addr, struct in_addr *dst_addr, struct sockaddr_ll *ME, @@ -299,7 +302,7 @@ int arping_main(int argc UNUSED_PARAM, char **argv) INIT_G(); - sock_fd = xsocket(AF_PACKET, SOCK_DGRAM, 0); + xmove_fd(xsocket(AF_PACKET, SOCK_DGRAM, 0), sock_fd); // If you ever change BB_SUID_DROP to BB_SUID_REQUIRE, // drop suid root privileges here: @@ -351,31 +354,29 @@ int arping_main(int argc UNUSED_PARAM, char **argv) src = dst; if (!(option_mask32 & DAD) || src.s_addr) { - struct sockaddr_in saddr; + /*struct sockaddr_in probe_saddr;*/ int probe_fd = xsocket(AF_INET, SOCK_DGRAM, 0); setsockopt_bindtodevice(probe_fd, device); - memset(&saddr, 0, sizeof(saddr)); - saddr.sin_family = AF_INET; + + /*memset(&G.probe_saddr, 0, sizeof(G.probe_saddr)); - zeroed by INIT_G */ + G.probe_saddr.sin_family = AF_INET; if (src.s_addr) { /* Check that this is indeed our IP */ - saddr.sin_addr = src; - xbind(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr)); + G.probe_saddr.sin_addr = src; + xbind(probe_fd, (struct sockaddr *) &G.probe_saddr, sizeof(G.probe_saddr)); } else { /* !(option_mask32 & DAD) case */ /* Find IP address on this iface */ - saddr.sin_port = htons(1025); - saddr.sin_addr = dst; + G.probe_saddr.sin_port = htons(1025); + G.probe_saddr.sin_addr = dst; if (setsockopt_SOL_SOCKET_1(probe_fd, SO_DONTROUTE) != 0) bb_perror_msg("setsockopt(%s)", "SO_DONTROUTE"); - xconnect(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr)); - bb_getsockname(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr)); - //never happens: - //if (getsockname(probe_fd, (struct sockaddr *) &saddr, &alen) == -1) - // bb_perror_msg_and_die("getsockname"); - if (saddr.sin_family != AF_INET) + xconnect(probe_fd, (struct sockaddr *) &G.probe_saddr, sizeof(G.probe_saddr)); + bb_getsockname(probe_fd, (struct sockaddr *) &G.probe_saddr, sizeof(G.probe_saddr)); + if (G.probe_saddr.sin_family != AF_INET) bb_error_msg_and_die("no IP address configured"); - src = saddr.sin_addr; + src = G.probe_saddr.sin_addr; } close(probe_fd); } |