diff options
| -rw-r--r-- | networking/arping.c | 75 |
1 files changed, 34 insertions, 41 deletions
diff --git a/networking/arping.c b/networking/arping.c index 97e9e68..a16f04b 100644 --- a/networking/arping.c +++ b/networking/arping.c @@ -79,8 +79,11 @@ struct globals { unsigned received; unsigned brd_recv; unsigned req_recv; + + struct ifreq ifr; + sigset_t sset; + unsigned char packet[4096]; } FIX_ALIASING; -#define G (*(struct globals*)bb_common_bufsiz1) #define src (G.src ) #define dst (G.dst ) #define me (G.me ) @@ -95,8 +98,11 @@ struct globals { #define received (G.received ) #define brd_recv (G.brd_recv ) #define req_recv (G.req_recv ) +//#define G (*(struct globals*)bb_common_bufsiz1) +#define G (*ptr_to_globals) #define INIT_G() do { \ - setup_common_bufsiz(); \ + /*setup_common_bufsiz();*/ \ + SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ count = -1; \ } while (0) @@ -183,15 +189,10 @@ static void recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM) struct arphdr *ah = (struct arphdr *) buf; unsigned char *p = (unsigned char *) (ah + 1); struct in_addr src_ip, dst_ip; + /* moves below assume in_addr is 4 bytes big, ensure that */ - struct BUG_in_addr_must_be_4 { - char BUG_in_addr_must_be_4[ - sizeof(struct in_addr) == 4 ? 1 : -1 - ]; - char BUG_s_addr_must_be_4[ - sizeof(src_ip.s_addr) == 4 ? 1 : -1 - ]; - }; + BUILD_BUG_ON(sizeof(struct in_addr) != 4); + BUILD_BUG_ON(sizeof(src_ip.s_addr) != 4); /* Filter out wild packets */ if (FROM->sll_pkttype != PACKET_HOST @@ -212,8 +213,10 @@ static void recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM) if (ah->ar_pro != htons(ETH_P_IP) || (ah->ar_pln != 4) || (ah->ar_hln != me.sll_halen) - || (len < (int)(sizeof(*ah) + 2 * (4 + ah->ar_hln)))) + || (len < (int)(sizeof(*ah) + 2 * (4 + ah->ar_hln))) + ) { return; + } move_from_unaligned32(src_ip.s_addr, p + ah->ar_hln); move_from_unaligned32(dst_ip.s_addr, p + ah->ar_hln + 4 + ah->ar_hln); @@ -292,7 +295,6 @@ int arping_main(int argc UNUSED_PARAM, char **argv) const char *device = "eth0"; char *source = NULL; char *target; - unsigned char *packet; char *err_str; INIT_G(); @@ -316,27 +318,21 @@ int arping_main(int argc UNUSED_PARAM, char **argv) err_str = xasprintf("interface %s %%s", device); xfunc_error_retval = 2; - { - struct ifreq ifr; - - memset(&ifr, 0, sizeof(ifr)); - strncpy_IFNAMSIZ(ifr.ifr_name, device); - /* We use ifr.ifr_name in error msg so that problem - * with truncated name will be visible */ - ioctl_or_perror_and_die(sock_fd, SIOCGIFINDEX, &ifr, err_str, "not found"); - me.sll_ifindex = ifr.ifr_ifindex; + /*memset(&G.ifr, 0, sizeof(G.ifr)); - zeroed by INIT_G */ + strncpy_IFNAMSIZ(G.ifr.ifr_name, device); + ioctl_or_perror_and_die(sock_fd, SIOCGIFINDEX, &G.ifr, err_str, "not found"); + me.sll_ifindex = G.ifr.ifr_ifindex; - xioctl(sock_fd, SIOCGIFFLAGS, (char *) &ifr); + xioctl(sock_fd, SIOCGIFFLAGS, (char *) &G.ifr); - if (!(ifr.ifr_flags & IFF_UP)) { - bb_error_msg_and_die(err_str, "is down"); - } - if (ifr.ifr_flags & (IFF_NOARP | IFF_LOOPBACK)) { - bb_error_msg(err_str, "is not ARPable"); - BUILD_BUG_ON(DAD != 2); - /* exit 0 if DAD, else exit 2 */ - return (~option_mask32 & DAD); - } + if (!(G.ifr.ifr_flags & IFF_UP)) { + bb_error_msg_and_die(err_str, "is down"); + } + if (G.ifr.ifr_flags & (IFF_NOARP | IFF_LOOPBACK)) { + bb_error_msg(err_str, "is not ARPable"); + BUILD_BUG_ON(DAD != 2); + /* exit 0 if DAD, else exit 2 */ + return (~option_mask32 & DAD); } /* if (!inet_aton(target, &dst)) - not needed */ { @@ -413,8 +409,9 @@ int arping_main(int argc UNUSED_PARAM, char **argv) printf(" from %s %s\n", inet_ntoa(src), device); } - packet = xmalloc(4096); - + /*sigemptyset(&G.sset); - zeroed by INIT_G */ + sigaddset(&G.sset, SIGALRM); + sigaddset(&G.sset, SIGINT); signal_SA_RESTART_empty_mask(SIGINT, (void (*)(int))finish); signal_SA_RESTART_empty_mask(SIGALRM, (void (*)(int))catcher); @@ -422,28 +419,24 @@ int arping_main(int argc UNUSED_PARAM, char **argv) catcher(); while (1) { - sigset_t sset; struct sockaddr_ll from; socklen_t alen = sizeof(from); int cc; - sigemptyset(&sset); - sigaddset(&sset, SIGALRM); - sigaddset(&sset, SIGINT); /* Unblock SIGALRM so that the previously called alarm() * can prevent recvfrom from blocking forever in case the * inherited procmask is blocking SIGALRM. */ - sigprocmask(SIG_UNBLOCK, &sset, NULL); + sigprocmask(SIG_UNBLOCK, &G.sset, NULL); - cc = recvfrom(sock_fd, packet, 4096, 0, (struct sockaddr *) &from, &alen); + cc = recvfrom(sock_fd, G.packet, sizeof(G.packet), 0, (struct sockaddr *) &from, &alen); /* Don't allow SIGALRMs while we process the reply */ - sigprocmask(SIG_BLOCK, &sset, NULL); + sigprocmask(SIG_BLOCK, &G.sset, NULL); if (cc < 0) { bb_perror_msg("recvfrom"); continue; } - recv_pack(packet, cc, &from); + recv_pack(G.packet, cc, &from); } } |