diff options
| -rw-r--r-- | toys/pending/ping.c | 221 |
1 files changed, 173 insertions, 48 deletions
diff --git a/toys/pending/ping.c b/toys/pending/ping.c index 545ad79c..3802918d 100644 --- a/toys/pending/ping.c +++ b/toys/pending/ping.c @@ -3,8 +3,14 @@ * Copyright 2014 Rob Landley <rob@landley.net> * * Not in SUSv4. + * + * Note: ping_group_range should never have existed. To disable it, do: + * echo 0 $(((1<<31)-1)) > /proc/sys/net/ipv4/ping_group_range + * (Android does this by default in its init script.) + * + * Yes, I wimped out and capped -s at sizeof(toybuf), waiting for a complaint... -USE_PING(NEWTOY(ping, "<1>1t#<0>255c#<0s#<0>65535I:W#<0w#<0q46[-46]", TOYFLAG_ROOTONLY|TOYFLAG_USR|TOYFLAG_BIN)) +USE_PING(NEWTOY(ping, "<1>1t#<0>255=64c#<0=3s#<0>4088=56I:i:W#<0=10w#<0qf46[-46]", TOYFLAG_ROOTONLY|TOYFLAG_USR|TOYFLAG_BIN)) config PING bool "ping" @@ -16,16 +22,18 @@ config PING its response. Send ICMP ECHO_REQUEST packets to ipv4 or ipv6 addresses and prints each - echo it receives back, with round trip time. + echo it receives back, with round trip time. Returns true if host alive. Options: -4, -6 Force IPv4 or IPv6 - -c CNT Send CNT many packets + -c CNT Send CNT many packets (default 3, 0 = infinite) + -f Flood (. on send, backspace on receive, to show packet drops) + -i TIME Interval between packets (default 1, need root for < .2) -I IFACE/IP Source interface or address - -q Quiet, only displays output at start and when finished - -s SIZE Packet SIZE in bytes (default 56) - -t TTL Set Time (number of hops) To Live - -W SEC Seconds to wait for response after all packets sent (default 10) + -q Quiet (stops after one returns true if host is alive) + -s SIZE Data SIZE in bytes (default 56) + -t TTL Set Time To Live (number of hops) + -W SEC Seconds to wait for response after -c (default 10) -w SEC Exit after this many seconds */ @@ -33,23 +41,44 @@ config PING #include "toys.h" #include <ifaddrs.h> +#include <netinet/ip_icmp.h> GLOBALS( - long wait_exit; - long wait_resp; - char *iface; - long size; - long count; - long ttl; + long w; + long W; + char *i; + char *I; + long s; + long c; + long t; int sock; + long i_ms; ) -void *sock2addr(struct sockaddr *sa) +static void xsendto(int sockfd, void *buf, size_t len, struct sockaddr *dest) +{ + int rc = sendto(TT.sock, buf, len, 0, dest, + dest->sa_family == AF_INET ? sizeof(struct sockaddr_in) : + sizeof(struct sockaddr_in6)); + + if (rc != len) perror_exit("sendto"); +} + +// assumes aligned and can read even number of bytes +static unsigned short pingchksum(unsigned short *data, int len) { - if (sa->sa_family == AF_INET) - return &((struct sockaddr_in *)sa)->sin_addr; - return &((struct sockaddr_in6 *)sa)->sin6_addr; + unsigned short u = 0, d; + + // circular carry is endian independent: bits from high byte go to low byte + while (len>0) { + d = *data++; + if (len == 1) d &= 255<<IS_BIG_ENDIAN; + if (d >= (u += d)) u++; + len -= 2; + } + + return u; } void ping_main(void) @@ -59,41 +88,55 @@ void ping_main(void) union { struct sockaddr_in in; struct sockaddr_in6 in6; - } src_addr; - struct sockaddr *sa = (void *)&src_addr; - int family = 0; - - // no 4/6 specified: -I has only one, arg must match - // no 4/6 specified: arg is one, -I must match - // 4/6 specified, both must match - - if (!(toys.optflags&FLAG_s)) TT.size = 56; // 64-PHDR_LEN + } src_addr, src_addr2; + struct sockaddr *sa = (void *)&src_addr, *sa2 = (void *)&src_addr2; + struct pollfd pfd; + int family = 0, sent = 0, len; + long long tnext, tW, tnow, tw; + unsigned short seq = 0; + struct icmphdr *ih = (void *)toybuf; + + // Interval + if (TT.i) { + long frac; + + TT.i_ms = xparsetime(TT.i, 1000, &frac) * 1000; + TT.i_ms += frac; + if (TT.i_ms<200 && getuid()) error_exit("need root for -i <200"); + } else TT.i_ms = 1000; + if (!(toys.optflags&FLAG_s)) TT.s = 56; // 64-PHDR_LEN + + // ipv4 or ipv6? (0 = autodetect if -I or arg have only one address type.) if (toys.optflags&FLAG_6) family = AF_INET6; else if (toys.optflags&FLAG_4) family = AF_INET; else family = 0; // If -I src_addr look it up. Allow numeric address of correct type. memset(&src_addr, 0, sizeof(src_addr)); - if (TT.iface) { - if (!(toys.optflags&FLAG_6) && inet_pton(AF_INET, TT.iface, + if (TT.I) { + if (!(toys.optflags&FLAG_6) && inet_pton(AF_INET, TT.I, (void *)&src_addr.in.sin_addr)) - family = sa->sa_family = AF_INET; - else if (!(toys.optflags&FLAG_4) && inet_pton(AF_INET6, TT.iface, + family = AF_INET; + else if (!(toys.optflags&FLAG_4) && inet_pton(AF_INET6, TT.I, (void *)&src_addr.in6.sin6_addr)) - family = sa->sa_family = AF_INET6; + family = AF_INET6; else if (getifaddrs(&ifa2)) perror_exit("getifaddrs"); } - // Look up HOST address, filtering for correct type. + // Look up HOST address, filtering for correct type and interface. // If -I but no -46 then find compatible type between -I and HOST - ai2 = xgetaddrinfo(toys.optargs[0], 0, family, 0, 0, 0); + ai2 = xgetaddrinfo(*toys.optargs, 0, family, 0, 0, 0); for (ai = ai2; ai; ai = ai->ai_next) { + + // correct type? if (family && family!=ai->ai_family) continue; if (ai->ai_family!=AF_INET && ai->ai_family!=AF_INET6) continue; - if (!TT.iface || !ifa2) break; + + // correct interface? + if (!TT.I || !ifa2) break; for (ifa = ifa2; ifa; ifa = ifa->ifa_next) { if (!ifa->ifa_addr || ifa->ifa_addr->sa_family!=ai->ai_family - || strcmp(ifa->ifa_name, TT.iface)) continue; + || strcmp(ifa->ifa_name, TT.I)) continue; sa = (void *)ifa->ifa_addr; break; @@ -102,19 +145,101 @@ void ping_main(void) } if (!ai) - error_exit("no v%d addr for -I %s", 4+2*(family==AF_INET6), TT.iface); - - inet_ntop(family, sock2addr(sa), toybuf, sizeof(toybuf)); - printf("host=%s\n", toybuf); - *toybuf = 0; - inet_ntop(ai->ai_family, sock2addr(ai->ai_addr), toybuf, sizeof(toybuf)); - printf("targ=%s\n", toybuf); - - // Open raw socket - TT.sock = xsocket(ai->ai_family, SOCK_DGRAM, (ifa->ifa_addr->sa_family == AF_INET) ? - IPPROTO_ICMP : IPPROTO_ICMPV6); - if (TT.iface && bind(TT.sock, ifa->ifa_addr, sizeof(src_addr))) - perror_exit("bind"); + error_exit("no v%d addr for -I %s", 4+2*(family==AF_INET6), TT.I); + + // Open DGRAM socket + sa->sa_family = ai->ai_family; + TT.sock = xsocket(ai->ai_family, SOCK_DGRAM, + (ai->ai_family == AF_INET) ? IPPROTO_ICMP : IPPROTO_ICMPV6); + if (TT.I && bind(TT.sock, sa, sizeof(src_addr))) perror_exit("bind"); + + if (TT.t) { + len = TT.t; + + if (ai->ai_family == AF_INET) + setsockopt(TT.sock, IPPROTO_IP, IP_TTL, &len, 4); + else setsockopt(TT.sock, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &len, 4); + } + + if (!(toys.optflags&FLAG_q)) { + printf("Ping %s (%s)", *toys.optargs, ntop(ai->ai_addr)); + if (TT.I) { + *toybuf = 0; + printf(" from %s (%s)", TT.I, ntop(sa)); + } + // 20 byte TCP header, 8 byte ICMP header, plus data payload + printf(": %ld(%ld) bytes.\n", TT.s, TT.s+28); + } + toys.exitval = 1; + + tW = tw = 0; + tnext = millitime(); + if (TT.w) tw = TT.w*1000+tnext; + + // Send/receive packets + for (;;) { + int waitms = INT_MAX; + + // Exit due to timeout? (TODO: timeout is after last packet, waiting if + // any packets ever dropped. Not timeout since packet was dropped.) + tnow = millitime(); + if (tW) if (0>=(waitms = tW-tnow) || !sent) break; + if (tw) { + if (tnow>tw) break; + else if (waitms>tw-tnow) waitms = tw-tnow; + // Time to send the next packet? + } else if (tnext-tnow <= 0) { + tnext += TT.i_ms; + + memset(ih, 0, sizeof(*ih)); + ih->type = (ai->ai_family == AF_INET) ? 8 : 128; + ih->un.echo.id = getpid(); + ih->un.echo.sequence = ++seq; + if (TT.s >= 4) *(unsigned *)(ih+1) = tnow; + + ih->checksum = 0; + ih->checksum = pingchksum((void *)toybuf, TT.s+sizeof(*ih)); + xsendto(TT.sock, toybuf, TT.s+sizeof(*ih), ai->ai_addr); + sent++; + if (toys.optflags&FLAG_f) printf("."); + + // last packet? + if (TT.c) if (!--TT.c) { + if (!TT.W) break; + tW = tnow + TT.W*1000; + } + } + + // This is down here so it's against new period if we just sent a packet + if (!tw && waitms>tnext-tnow) waitms = tnext-tnow; + + // wait for next packet or timeout + + if (waitms<0) waitms = 0; + pfd.fd = TT.sock; + pfd.events = POLLIN; + if (0>(len = poll(&pfd, 1, waitms))) break; + if (!len) continue; + + len = sizeof(src_addr2); + len = recvfrom(TT.sock, toybuf, sizeof(toybuf), 0, sa2, (void *)&len); + sent--; + + // reply id == 0 for ipv4, 129 for ipv6 + + if (!(toys.optflags&FLAG_q)) { + printf("%d bytes from %s: icmp_seq=%d ttl=%d", len, ntop(sa2), + ih->un.echo.sequence, 0); + if (len >= sizeof(*ih)+4) { + unsigned lunchtime = millitime()-*(unsigned *)(ih+1); + + printf(" time=%u.%03u", lunchtime/1000, lunchtime%1000); + } + xputc('\n'); + } + + toys.exitval = 0; + } if (CFG_TOYBOX_FREE) { freeaddrinfo(ai2); |