diff --git a/common/bpf.c b/common/bpf.c index b0ef657..8bd5727 100644 --- a/common/bpf.c +++ b/common/bpf.c @@ -485,7 +485,7 @@ ssize_t receive_packet (interface, buf, len, from, hfrom) offset = decode_udp_ip_header (interface, interface -> rbuf, interface -> rbuf_offset, - from, hdr.bh_caplen, &paylen); + from, hdr.bh_caplen, &paylen, 0); /* If the IP or UDP checksum was bad, skip the packet... */ if (offset < 0) { diff --git a/common/dlpi.c b/common/dlpi.c index 8f2c73d..b9eb1d3 100644 --- a/common/dlpi.c +++ b/common/dlpi.c @@ -693,7 +693,7 @@ ssize_t receive_packet (interface, buf, len, from, hfrom) length -= offset; #endif offset = decode_udp_ip_header (interface, dbuf, bufix, - from, length, &paylen); + from, length, &paylen, 0); /* * If the IP or UDP checksum was bad, skip the packet... diff --git a/common/lpf.c b/common/lpf.c index 16eecc9..4bdb0f1 100644 --- a/common/lpf.c +++ b/common/lpf.c @@ -29,19 +29,33 @@ #include "dhcpd.h" #if defined (USE_LPF_SEND) || defined (USE_LPF_RECEIVE) #include +#include #include #include #include #include #include +#include #include -#include #include "includes/netinet/ip.h" #include "includes/netinet/udp.h" #include "includes/netinet/if_ether.h" #include +#ifndef PACKET_AUXDATA +#define PACKET_AUXDATA 8 + +struct tpacket_auxdata +{ + __u32 tp_status; + __u32 tp_len; + __u32 tp_snaplen; + __u16 tp_mac; + __u16 tp_net; +}; +#endif + /* Reinitializes the specified interface after an address change. This is not required for packet-filter APIs. */ @@ -67,10 +81,14 @@ int if_register_lpf (info) struct interface_info *info; { int sock; - struct sockaddr sa; + union { + struct sockaddr_ll ll; + struct sockaddr common; + } sa; + struct ifreq ifr; /* Make an LPF socket. */ - if ((sock = socket(PF_PACKET, SOCK_PACKET, + if ((sock = socket(PF_PACKET, SOCK_RAW, htons((short)ETH_P_ALL))) < 0) { if (errno == ENOPROTOOPT || errno == EPROTONOSUPPORT || errno == ESOCKTNOSUPPORT || errno == EPFNOSUPPORT || @@ -85,11 +103,16 @@ int if_register_lpf (info) log_fatal ("Open a socket for LPF: %m"); } + memset (&ifr, 0, sizeof ifr); + strncpy (ifr.ifr_name, (const char *)info -> ifp, sizeof ifr.ifr_name); + if (ioctl (sock, SIOCGIFINDEX, &ifr)) + log_fatal ("Failed to get interface index: %m"); + /* Bind to the interface name */ memset (&sa, 0, sizeof sa); - sa.sa_family = AF_PACKET; - strncpy (sa.sa_data, (const char *)info -> ifp, sizeof sa.sa_data); - if (bind (sock, &sa, sizeof sa)) { + sa.ll.sll_family = AF_PACKET; + sa.ll.sll_ifindex = ifr.ifr_ifindex; + if (bind (sock, &sa.common, sizeof sa)) { if (errno == ENOPROTOOPT || errno == EPROTONOSUPPORT || errno == ESOCKTNOSUPPORT || errno == EPFNOSUPPORT || errno == EAFNOSUPPORT || errno == EINVAL) { @@ -171,9 +194,18 @@ static void lpf_gen_filter_setup (struct interface_info *); void if_register_receive (info) struct interface_info *info; { + int val; + /* Open a LPF device and hang it on this interface... */ info -> rfdesc = if_register_lpf (info); + val = 1; + if (setsockopt (info -> rfdesc, SOL_PACKET, PACKET_AUXDATA, &val, + sizeof val) < 0) { + if (errno != ENOPROTOOPT) + log_fatal ("Failed to set auxiliary packet data: %m"); + } + #if defined (HAVE_TR_SUPPORT) if (info -> hw_address.hbuf [0] == HTYPE_IEEE802) lpf_tr_filter_setup (info); @@ -295,7 +327,6 @@ ssize_t send_packet (interface, packet, raw, len, from, to, hto) double hh [16]; double ih [1536 / sizeof (double)]; unsigned char *buf = (unsigned char *)ih; - struct sockaddr_pkt sa; int result; int fudge; @@ -316,17 +347,7 @@ ssize_t send_packet (interface, packet, raw, len, from, to, hto) (unsigned char *)raw, len); memcpy (buf + ibufp, raw, len); - /* For some reason, SOCK_PACKET sockets can't be connected, - so we have to do a sentdo every time. */ - memset (&sa, 0, sizeof sa); - sa.spkt_family = AF_PACKET; - strncpy ((char *)sa.spkt_device, - (const char *)interface -> ifp, sizeof sa.spkt_device); - sa.spkt_protocol = htons(ETH_P_IP); - - result = sendto (interface -> wfdesc, - buf + fudge, ibufp + len - fudge, 0, - (const struct sockaddr *)&sa, sizeof sa); + result = write (interface -> wfdesc, buf + fudge, ibufp + len - fudge); if (result < 0) log_error ("send_packet: %m"); return result; @@ -343,14 +364,35 @@ ssize_t receive_packet (interface, buf, len, from, hfrom) { int length = 0; int offset = 0; + int nocsum = 0; unsigned char ibuf [1536]; unsigned bufix = 0; unsigned paylen; - - length = read (interface -> rfdesc, ibuf, sizeof ibuf); + unsigned char cmsgbuf[CMSG_LEN(sizeof(struct tpacket_auxdata))]; + struct iovec iov = { + .iov_base = ibuf, + .iov_len = sizeof ibuf, + }; + struct msghdr msg = { + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = cmsgbuf, + .msg_controllen = sizeof(cmsgbuf), + }; + struct cmsghdr *cmsg; + + length = recvmsg (interface -> rfdesc, &msg, 0); if (length <= 0) return length; + for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) { + if (cmsg->cmsg_level == SOL_PACKET && + cmsg->cmsg_type == PACKET_AUXDATA) { + struct tpacket_auxdata *aux = (void *)CMSG_DATA(cmsg); + nocsum = aux->tp_status & TP_STATUS_CSUMNOTREADY; + } + } + bufix = 0; /* Decode the physical header... */ offset = decode_hw_header (interface, ibuf, bufix, hfrom); @@ -367,7 +409,7 @@ ssize_t receive_packet (interface, buf, len, from, hfrom) /* Decode the IP and UDP headers... */ offset = decode_udp_ip_header (interface, ibuf, bufix, from, - (unsigned)length, &paylen); + (unsigned)length, &paylen, nocsum); /* If the IP or UDP checksum was bad, skip the packet... */ if (offset < 0) diff --git a/common/nit.c b/common/nit.c index 3822206..0da9c36 100644 --- a/common/nit.c +++ b/common/nit.c @@ -369,7 +369,7 @@ ssize_t receive_packet (interface, buf, len, from, hfrom) /* Decode the IP and UDP headers... */ offset = decode_udp_ip_header (interface, ibuf, bufix, - from, length, &paylen); + from, length, &paylen, 0); /* If the IP or UDP checksum was bad, skip the packet... */ if (offset < 0) diff --git a/common/packet.c b/common/packet.c index 42bca69..fd2d975 100644 --- a/common/packet.c +++ b/common/packet.c @@ -211,7 +211,7 @@ ssize_t decode_udp_ip_header(struct interface_info *interface, unsigned char *buf, unsigned bufix, struct sockaddr_in *from, unsigned buflen, - unsigned *rbuflen) + unsigned *rbuflen, int nocsum) { unsigned char *data; struct ip ip; @@ -322,7 +322,7 @@ decode_udp_ip_header(struct interface_info *interface, 8, IPPROTO_UDP + ulen)))); udp_packets_seen++; - if (usum && usum != sum) { + if (!nocsum && usum && usum != sum) { udp_packets_bad_checksum++; if (udp_packets_seen > 4 && (udp_packets_seen / udp_packets_bad_checksum) < 2) { diff --git a/common/upf.c b/common/upf.c index feb82a2..fff3949 100644 --- a/common/upf.c +++ b/common/upf.c @@ -320,7 +320,7 @@ ssize_t receive_packet (interface, buf, len, from, hfrom) /* Decode the IP and UDP headers... */ offset = decode_udp_ip_header (interface, ibuf, bufix, - from, length, &paylen); + from, length, &paylen, 0); /* If the IP or UDP checksum was bad, skip the packet... */ if (offset < 0) diff --git a/includes/dhcpd.h b/includes/dhcpd.h index adf04cc..ded57a9 100644 --- a/includes/dhcpd.h +++ b/includes/dhcpd.h @@ -2793,7 +2793,7 @@ ssize_t decode_hw_header (struct interface_info *, unsigned char *, unsigned, struct hardware *); ssize_t decode_udp_ip_header (struct interface_info *, unsigned char *, unsigned, struct sockaddr_in *, - unsigned, unsigned *); + unsigned, unsigned *, int); /* ethernet.c */ void assemble_ethernet_header (struct interface_info *, unsigned char *, -- 1.7.3.4