diff options
Diffstat (limited to 'meta/recipes-connectivity/dhcp/dhcp/dhcp-xen-checksum.patch')
-rw-r--r-- | meta/recipes-connectivity/dhcp/dhcp/dhcp-xen-checksum.patch | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/meta/recipes-connectivity/dhcp/dhcp/dhcp-xen-checksum.patch b/meta/recipes-connectivity/dhcp/dhcp/dhcp-xen-checksum.patch new file mode 100644 index 0000000000..62c279db12 --- /dev/null +++ b/meta/recipes-connectivity/dhcp/dhcp/dhcp-xen-checksum.patch @@ -0,0 +1,307 @@ +dhcp-client: Ignore partial checksums + +dhclient will fail to get an IP address if run inside a guest when traffic is +flowing over a virtual network interface. The user will see the error +message: + + 5 bad udp checksums in 5 packets + No DHCPOFFERS received. + Unable to obtain a lease on first try. Exiting. + Failed to bring up eth0. + +This is because Linux only uses partial checksums for packets that go over +virtual network interfaces and dhclient does not like this. + + See linux kernel commit 78ea85f17b15390e30d8b47488ec7b6cf0790663 + ("net: skbuff: improve comment on checksumming") + +An application can detect this behaviour by checking for the +TP_STATUS_CSUMNOTREADY flag in the tp_status field. + + See linux kernel commit 8dc4194474159660d7f37c495e3fc3f10d0db8cc + ("Add optional checksum computation for recvmsg") + +An extra parameter is added to decode_udp_ip_header() in dhclient to indicate +whether or not dhclient should ignore partial checksums. This is used +when the TP_STATUS_CSUMNOTREADY bit is set by the guest kernel. + +This fix has been included in Fedora and Ubuntu, however it has not yet been +accepted by ISC upstream. Likely because it is specific to behaviour in Linux +and other UNIX variants do not seem to be affected. + +The patch was imported from the dhcp source RPM in Fedora 21 + (http://pkgs.fedoraproject.org/cgit/dhcp.git/tree/dhcp-xen-checksum.patch?h=f21) + +Originally contributed to fedora-cvs-commit by David Cantrell on Jan 30 2007 + (https://www.redhat.com/archives/fedora-cvs-commits/2007-January/msg01442.html) + +Submitted to dhcp-bugs@isc.org - [ISC-Bugs #22806] - by Michael S. Tsirkin + (http://comments.gmane.org/gmane.comp.emulators.kvm.devel/65236) + (https://lists.isc.org/pipermail/dhcp-hackers/2010-April/001835.html) + +Upstream-Status: Submitted [dhcp-bugs@isc.org] +Signed-off-by: Rob Woolley <rob.woolley@windriver.com> +-- + common/bpf.c | 2 - + common/dlpi.c | 2 - + common/lpf.c | 83 +++++++++++++++++++++++++++++++++++++++++-------------- + common/nit.c | 2 - + common/packet.c | 4 +- + common/upf.c | 2 - + includes/dhcpd.h | 2 - + 7 files changed, 70 insertions(+), 27 deletions(-) + +diff --git a/common/bpf.c b/common/bpf.c +--- a/common/bpf.c ++++ b/common/bpf.c +@@ -481,7 +481,7 @@ ssize_t receive_packet (interface, buf, + /* Decode the IP and UDP headers... */ + 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 +--- a/common/dlpi.c ++++ b/common/dlpi.c +@@ -691,7 +691,7 @@ ssize_t receive_packet (interface, buf, + 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 +--- a/common/lpf.c ++++ b/common/lpf.c +@@ -29,14 +29,15 @@ + + #include "dhcpd.h" + #if defined (USE_LPF_SEND) || defined (USE_LPF_RECEIVE) ++#include <sys/socket.h> + #include <sys/uio.h> + #include <errno.h> + + #include <asm/types.h> + #include <linux/filter.h> + #include <linux/if_ether.h> ++#include <linux/if_packet.h> + #include <netinet/in_systm.h> +-#include <net/if_packet.h> + #include "includes/netinet/ip.h" + #include "includes/netinet/udp.h" + #include "includes/netinet/if_ether.h" +@@ -51,6 +52,19 @@ + /* Reinitializes the specified interface after an address change. This + is not required for packet-filter APIs. */ + ++#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 ++ + #ifdef USE_LPF_SEND + void if_reinitialize_send (info) + struct interface_info *info; +@@ -73,10 +87,14 @@ 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 || +@@ -91,11 +109,17 @@ 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); ++ ifr.ifr_name[IFNAMSIZ-1] = '\0'; ++ 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) { +@@ -177,9 +201,18 @@ static void lpf_gen_filter_setup (struct + 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); +@@ -301,7 +334,6 @@ ssize_t send_packet (interface, packet, + double hh [16]; + double ih [1536 / sizeof (double)]; + unsigned char *buf = (unsigned char *)ih; +- struct sockaddr_pkt sa; + int result; + int fudge; + +@@ -322,17 +354,7 @@ ssize_t send_packet (interface, packet, + (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; +@@ -349,14 +371,35 @@ ssize_t receive_packet (interface, buf, + { + int length = 0; + int offset = 0; ++ int nocsum = 0; + unsigned char ibuf [1536]; + unsigned bufix = 0; + unsigned paylen; ++ 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 = read (interface -> rfdesc, ibuf, sizeof ibuf); ++ 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); +@@ -373,7 +416,7 @@ ssize_t receive_packet (interface, buf, + + /* 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 +--- a/common/nit.c ++++ b/common/nit.c +@@ -363,7 +363,7 @@ ssize_t receive_packet (interface, buf, + + /* 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 +--- a/common/packet.c ++++ b/common/packet.c +@@ -226,7 +226,7 @@ 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; +@@ -337,7 +337,7 @@ decode_udp_ip_header(struct interface_in + 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 +--- a/common/upf.c ++++ b/common/upf.c +@@ -314,7 +314,7 @@ ssize_t receive_packet (interface, buf, + + /* 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 +--- a/includes/dhcpd.h ++++ b/includes/dhcpd.h +@@ -2857,7 +2857,7 @@ ssize_t decode_hw_header (struct interfa + 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 *, +-- +1.8.1.2 + |