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| author | Thomas Habets <thomas@habets.se> | 2016-05-08 15:27:38 +0100 |
|---|---|---|
| committer | Thomas Habets <thomas@habets.se> | 2016-05-08 15:31:14 +0100 |
| commit | e22a00772fb5370da914c943109471c9089c21df (patch) | |
| tree | 670dd77f70870633ecd8c6cf1deff35acb0fc2ea | |
| parent | 37b840ac6b008c8a55f1a974c87436bb8c2e3361 (diff) | |
| download | arping-e22a00772fb5370da914c943109471c9089c21df.tar.gz | |
Add padding to IP and MAC pings
Without this padding some systems (e.g. Raspberry Pi 3
wireless interface) failed. dmesg said:
arping: packet size is too short (42 <= 50)
| -rw-r--r-- | src/arping.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/src/arping.c b/src/arping.c index aefa06a..e65ccf4 100644 --- a/src/arping.c +++ b/src/arping.c @@ -834,6 +834,13 @@ static void pingmac_send(uint16_t id, uint16_t seq) { static libnet_ptag_t icmp = 0, ipv4 = 0,eth=0; + + // Padding size chosen fairly arbitrarily. + // Without this padding some systems (e.g. Raspberry Pi 3 + // wireless interface) failed. dmesg said: + // arping: packet size is too short (42 <= 50) + const char padding[16] = {0}; + int c; if (-1 == (icmp = libnet_build_icmpv4_echo(ICMP_ECHO, /* type */ @@ -841,8 +848,8 @@ pingmac_send(uint16_t id, uint16_t seq) 0, /* checksum */ id, /* id */ seq, /* seq */ - NULL, /* payload */ - 0, /* payload len */ + padding, /* payload */ + sizeof padding, /* payload len */ libnet, icmp))) { fprintf(stderr, "libnet_build_icmpv4_echo(): %s\n", @@ -918,6 +925,13 @@ static void pingip_send() { static libnet_ptag_t arp=0,eth=0; + + // Padding size chosen fairly arbitrarily. + // Without this padding some systems (e.g. Raspberry Pi 3 + // wireless interface) failed. dmesg said: + // arping: packet size is too short (42 <= 50) + const char padding[16] = {0}; + if (-1 == (arp = libnet_build_arp(ARPHRD_ETHER, ETHERTYPE_IP, ETH_ALEN, @@ -927,8 +941,8 @@ pingip_send() (uint8_t*)&srcip, unsolicited ? (uint8_t*)ethxmas : (uint8_t*)ethnull, (uint8_t*)&dstip, - NULL, - 0, + padding, + sizeof padding, libnet, arp))) { fprintf(stderr, "arping: libnet_build_arp(): %s\n", |