On 03/08/2018 08:11 AM, Chen Hanxiao wrote: > From: Chen Hanxiao <chenhanxiao@xxxxxxxxx> > > introduce helper to parse RTM_GETNEIGH query message and > store it in struct virArpTable. > > Signed-off-by: Chen Hanxiao <chenhanxiao@xxxxxxxxx> > --- > v4-rebase: > fit split Makefile.am > fit new virMacAddr fields > > v4: > use netlink query instead of parsing /proc/net/arp > > v3: > s/virGetArpTable/virArpTableGet > alloc virArpTable in virArpTableGet > return ENOSUPP on none-Linux platform > move helpers to virarptable.[ch] > > po/POTFILES.in | 1 + > src/Makefile.am | 1 + > src/libvirt_private.syms | 5 ++ > src/util/Makefile.inc.am | 2 + > src/util/virarptable.c | 181 +++++++++++++++++++++++++++++++++++++++++++++++ > src/util/virarptable.h | 48 +++++++++++++ > 6 files changed, 238 insertions(+) > create mode 100644 src/util/virarptable.c > create mode 100644 src/util/virarptable.h > > diff --git a/po/POTFILES.in b/po/POTFILES.in > index cfdd4ebdd..71c61dec9 100644 > --- a/po/POTFILES.in > +++ b/po/POTFILES.in > @@ -192,6 +192,7 @@ src/uml/uml_conf.c > src/uml/uml_driver.c > src/util/iohelper.c > src/util/viralloc.c > +src/util/virarptable.c > src/util/viraudit.c > src/util/virauth.c > src/util/virauthconfig.c > diff --git a/src/Makefile.am b/src/Makefile.am > index 8b1e4c8a4..82c5d5cde 100644 > --- a/src/Makefile.am > +++ b/src/Makefile.am > @@ -672,6 +672,7 @@ noinst_LTLIBRARIES += libvirt-setuid-rpc-client.la > libvirt_setuid_rpc_client_la_SOURCES = \ > util/viralloc.c \ > util/virarch.c \ > + util/virarptable.c \ > util/viratomic.c \ > util/viratomic.h \ > util/virbitmap.c \ > diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms > index 11b9f4937..05b0c5b0e 100644 > --- a/src/libvirt_private.syms > +++ b/src/libvirt_private.syms > @@ -1365,6 +1365,11 @@ virArchGetWordSize; > virArchToString; > > > +# util/virarptable.h > +virArpTableFree; > +virArpTableGet; > + > + > # util/viraudit.h > virAuditClose; > virAuditEncode; > diff --git a/src/util/Makefile.inc.am b/src/util/Makefile.inc.am > index a91b30dca..02d9c42cc 100644 > --- a/src/util/Makefile.inc.am > +++ b/src/util/Makefile.inc.am > @@ -5,6 +5,8 @@ UTIL_SOURCES = \ > util/viralloc.h \ > util/virarch.c \ > util/virarch.h \ > + util/virarptable.c \ > + util/virarptable.h \ > util/viratomic.c \ > util/viratomic.h \ > util/viraudit.c \ > diff --git a/src/util/virarptable.c b/src/util/virarptable.c > new file mode 100644 > index 000000000..cb56338eb > --- /dev/null > +++ b/src/util/virarptable.c > @@ -0,0 +1,181 @@ > +/* > + * virarptable.c Linux ARP table handling > + * > + * Copyright (C) 2018 Chen Hanxiao > + * > + * This library is free software; you can redistribute it and/or > + * modify it under the terms of the GNU Lesser General Public > + * License as published by the Free Software Foundation; either > + * version 2.1 of the License, or (at your option) any later version. > + * > + * This library is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * Lesser General Public License for more details. > + * > + * You should have received a copy of the GNU Lesser General Public > + * License along with this library. If not, see > + * <http://www.gnu.org/licenses/>. > + * > + * Authors: > + * Chen Hanxiao <chenhanxiao@xxxxxxxxx> > + */ > + > +#include <config.h> > + > +#include <stdlib.h> > +#include <stdio.h> > +#include <arpa/inet.h> > + > +#include "viralloc.h" > +#include "virarptable.h" > +#include "virfile.h" > +#include "virlog.h" > +#include "virnetlink.h" > +#include "virsocketaddr.h" > +#include "virstring.h" > + > +#define VIR_FROM_THIS VIR_FROM_NONE > + > +VIR_LOG_INIT("util.arptable"); > + > +#ifdef __linux__ > + > +# define NDA_RTA(r) \ > + ((struct rtattr*)(((char*)(r)) + NLMSG_ALIGN(sizeof(struct ndmsg)))) > + > +static int > +parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len) > +{ > + memset(tb, 0, sizeof(struct rtattr *) * (max + 1)); > + while (RTA_OK(rta, len)) { > + if ((rta->rta_type <= max) && (!tb[rta->rta_type])) > + tb[rta->rta_type] = rta; > + rta = RTA_NEXT(rta, len); > + } > + > + if (len) > + VIR_WARN("malformed netlink message: Deficit %d, rta_len=%d", > + len, rta->rta_len); > + return 0; > +} > + > +virArpTablePtr virArpTableGet(void) > +{ > + int num = 0; > + int msglen; > + void *nlData = NULL; > + virArpTablePtr table = NULL; > + char *ipstr = NULL; > + struct nlmsghdr* nh; > + struct rtattr * tb[NDA_MAX+1]; > + > + msglen = virNetlinkGetNeighbor(&nlData, 0, 0); > + if (msglen < 0) > + return NULL; > + > + if (VIR_ALLOC(table) < 0) > + return NULL; > + > + nh = (struct nlmsghdr*)nlData; > + > + while (NLMSG_OK(nh, msglen)) { > + struct ndmsg *r = NLMSG_DATA(nh); > + int len = nh->nlmsg_len; > + void *addr; > + > + if ((len -= NLMSG_LENGTH(sizeof(*nh))) < 0) { > + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", > + _("wrong nlmsg len")); > + goto cleanup; > + } > + > + if (r->ndm_family && (r->ndm_family != AF_INET)) > + goto next_nlmsg; > + > + /* catch stale and reachalbe arp entry only */ > + if (r->ndm_state && > + (!(r->ndm_state == NUD_STALE || r->ndm_state == NUD_REACHABLE))) { > + nh = NLMSG_NEXT(nh, msglen); > + continue; > + } > + > + if (nh->nlmsg_type == NLMSG_DONE) > + goto end_of_netlink_messages; > + > + parse_rtattr(tb, NDA_MAX, NDA_RTA(r), > + nh->nlmsg_len - NLMSG_LENGTH(sizeof(*r))); > + > + if (tb[NDA_DST] == NULL || tb[NDA_LLADDR] == NULL) > + goto next_nlmsg; > + > + if (tb[NDA_DST]) { > + virSocketAddr virAddr; > + if (VIR_REALLOC_N(table->t, num + 1) < 0) > + goto cleanup; > + > + table->n = num + 1; > + > + addr = RTA_DATA(tb[NDA_DST]); > + bzero(&virAddr, sizeof(virAddr)); > + virAddr.len = sizeof(virAddr.data.inet4); > + virAddr.data.inet4.sin_family = AF_INET; > + virAddr.data.inet4.sin_addr = *(struct in_addr *)addr; > + ipstr = virSocketAddrFormat(&virAddr); > + > + if (VIR_STRDUP(table->t[num].ipaddr, ipstr) < 0) > + goto cleanup; > + > + VIR_FREE(ipstr); > + } > + > + if (tb[NDA_LLADDR]) { > + virMacAddr macaddr; > + char ifmac[VIR_MAC_STRING_BUFLEN]; > + > + addr = RTA_DATA(tb[NDA_LLADDR]); > + memcpy(macaddr.addr, addr, VIR_MAC_BUFLEN); > + > + virMacAddrFormat(&macaddr, ifmac); > + > + if (VIR_STRDUP(table->t[num].mac, ifmac) < 0) > + goto cleanup; > + > + num++; > + } > + > + next_nlmsg: > + nh = NLMSG_NEXT(nh, msglen); > + } > + > + end_of_netlink_messages: > + VIR_FREE(nlData); > + return table; > + > + cleanup: > + VIR_FREE(ipstr); > + VIR_FREE(nlData); > + return NULL; > +} > + > +#else > + > +virArpTablePtr virArpTableGet(void) > +{ > + virReportError(VIR_ERR_NO_SUPPORT, "%s", > + _("get arp table not implemented on this platform")); > + return NULL; > +} > + > +#endif /* __linux__ */ > + > +void > +virArpTableFree(virArpTablePtr table) > +{ > + size_t i; > + for (i = 0; i < table->n; i++) { > + VIR_FREE(table->t[i].ipaddr); > + VIR_FREE(table->t[i].mac); > + } You need to free table->t too. > + VIR_FREE(table); > +} Michal -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
