From acccd780df517b0e5925de4497688b6238bee10c Mon Sep 17 00:00:00 2001
From: Hangbin Liu <haliu@redhat.com>
Date: Mon, 6 Aug 2018 22:02:09 +0800
Subject: [PATCH 7/8] ndptool: add -T target support
Currently ndptool can send a Neighbour Solicitation, but does not target
an IP address, so the NS packet doesn't really make sense.
Extend ndptool to target a destination for Neighbour Solicitation.
v2:
1) remove function ipv6_addr_is_multicast()
2) inline some help functions.
3) update code style.
4) rename parameter -d/--dest to -T/--target
Signed-off-by: Hangbin Liu <haliu@redhat.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
---
include/ndp.h | 2 +
libndp/libndp.c | 121 ++++++++++++++++++++++++++++++++++++++++++++++++
man/ndptool.8 | 4 ++
utils/ndptool.c | 21 +++++++--
4 files changed, 145 insertions(+), 3 deletions(-)
diff --git a/include/ndp.h b/include/ndp.h
index 0dc1468..698bba7 100644
--- a/include/ndp.h
+++ b/include/ndp.h
@@ -79,6 +79,8 @@ enum ndp_msg_type ndp_msg_type(struct ndp_msg *msg);
struct in6_addr *ndp_msg_addrto(struct ndp_msg *msg);
uint32_t ndp_msg_ifindex(struct ndp_msg *msg);
void ndp_msg_ifindex_set(struct ndp_msg *msg, uint32_t ifindex);
+void ndp_msg_target_set(struct ndp_msg *msg, struct in6_addr *target);
+void ndp_msg_opt_set(struct ndp_msg *msg);
int ndp_msg_send(struct ndp *ndp, struct ndp_msg *msg);
int ndp_msg_send_with_flags(struct ndp *ndp, struct ndp_msg *msg, uint8_t flags);
diff --git a/libndp/libndp.c b/libndp/libndp.c
index baacb76..bec55d4 100644
--- a/libndp/libndp.c
+++ b/libndp/libndp.c
@@ -32,10 +32,14 @@
#include <net/ethernet.h>
#include <assert.h>
#include <ndp.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
#include "ndp_private.h"
#include "list.h"
+#define pr_err(args...) fprintf(stderr, ##args)
+
/**
* SECTION: logging
* @short_description: libndp logging facility
@@ -308,6 +312,23 @@ static void ndp_msg_addrto_adjust_all_routers(struct in6_addr *addr)
addr->s6_addr32[3] = htonl(0x2);
}
+/*
+ * compute link-local solicited-node multicast address
+ */
+static void ndp_msg_addrto_adjust_solicit_multi(struct in6_addr *addr,
+ struct in6_addr *target)
+{
+ struct in6_addr any = IN6ADDR_ANY_INIT;
+
+ /* Don't set addr to target if target is default IN6ADDR_ANY_INIT */
+ if (!memcmp(target, &any, sizeof(any)))
+ return;
+ addr->s6_addr32[0] = htonl(0xFF020000);
+ addr->s6_addr32[1] = 0;
+ addr->s6_addr32[2] = htonl(0x1);
+ addr->s6_addr32[3] = htonl(0xFF000000) | target->s6_addr32[3];
+}
+
static bool ndp_msg_addrto_validate_link_local(struct in6_addr *addr)
{
return IN6_IS_ADDR_LINKLOCAL (addr);
@@ -679,6 +700,106 @@ void ndp_msg_ifindex_set(struct ndp_msg *msg, uint32_t ifindex)
msg->ifindex = ifindex;
}
+/**
+ * ndp_msg_target_set:
+ * @msg: message structure
+ * @target: ns,na target
+ *
+ * Set target address for NS and NA.
+ **/
+NDP_EXPORT
+void ndp_msg_target_set(struct ndp_msg *msg, struct in6_addr *target)
+{
+ enum ndp_msg_type msg_type = ndp_msg_type(msg);
+ switch (msg_type) {
+ case NDP_MSG_NS:
+ ((struct ndp_msgna*)&msg->nd_msg)->na->nd_na_target = *target;
+ /*
+ * Neighbor Solicitations are multicast when the node
+ * needs to resolve an address and unicast when the
+ * node seeks to verify the reachability of a
+ * neighbor.
+ *
+ * In this case we don't know if we have a cache of
+ * target, so we use multicast to resolve the target
+ * address.
+ * */
+ ndp_msg_addrto_adjust_solicit_multi(&msg->addrto, target);
+ break;
+ case NDP_MSG_NA:
+ ((struct ndp_msgns*)&msg->nd_msg)->ns->nd_ns_target = *target;
+ break;
+ default:
+ break;
+ }
+}
+
+static int ndp_get_iface_mac(int ifindex, char *ptr)
+{
+ int sockfd;
+ struct ifreq ifr;
+
+ sockfd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (sockfd == -1) {
+ pr_err("%s: Failed to create socket", __func__);
+ return -errno;
+ }
+
+ if (if_indextoname(ifindex, (char *)&ifr.ifr_name) == NULL) {
+ pr_err("%s: Failed to get iface name with index %d", __func__, ifindex);
+ return -errno;
+ }
+
+ if (ioctl(sockfd, SIOCGIFHWADDR, &ifr) < 0) {
+ pr_err("%s: Failed to get iface mac with index %d\n", __func__, ifindex);
+ return -errno;
+ }
+
+ memcpy(ptr, &ifr.ifr_hwaddr.sa_data, sizeof(ifr.ifr_hwaddr.sa_data));
+
+ return 0;
+}
+
+static void ndp_msg_opt_set_linkaddr(struct ndp_msg *msg, int ndp_opt)
+{
+ char *opts_start = ndp_msg_payload_opts(msg);
+ struct nd_opt_hdr *s_laddr_opt = (struct nd_opt_hdr *) opts_start;
+ char *opt_data = (char *) s_laddr_opt + sizeof(struct nd_opt_hdr);
+ int err;
+
+ err = ndp_get_iface_mac(ndp_msg_ifindex(msg), opt_data);
+ if (err)
+ return;
+
+ opt_data += 6;
+ s_laddr_opt->nd_opt_type = ndp_opt;
+ s_laddr_opt->nd_opt_len = (opt_data - opts_start) >> 3;
+ msg->len += opt_data - opts_start;
+}
+
+/**
+ * ndp_msg_opt_set:
+ * @msg: message structure
+ *
+ * Set neighbor discovery option info.
+ **/
+NDP_EXPORT
+void ndp_msg_opt_set(struct ndp_msg *msg)
+{
+ enum ndp_msg_type msg_type = ndp_msg_type(msg);
+
+ switch (msg_type) {
+ case NDP_MSG_NS:
+ ndp_msg_opt_set_linkaddr(msg, ND_OPT_SOURCE_LINKADDR);
+ break;
+ case NDP_MSG_NA:
+ ndp_msg_opt_set_linkaddr(msg, ND_OPT_TARGET_LINKADDR);
+ break;
+ default:
+ break;
+ }
+}
+
/**
* ndp_msg_send:
* @ndp: libndp library context
diff --git a/man/ndptool.8 b/man/ndptool.8
index ef765dc..dd6ddee 100644
--- a/man/ndptool.8
+++ b/man/ndptool.8
@@ -41,6 +41,10 @@ Neighbor Advertisement.
.B "\-i ifname, \-\-ifname ifname"
Specified interface name.
+.TP
+.B "\-T target, \-\-target target"
+Specified target address for NS/NA message.
+
.TP
.B "\-U, \-\-unsolicited"
Send Unsolicited NA.
diff --git a/utils/ndptool.c b/utils/ndptool.c
index 96479fa..ba24d75 100644
--- a/utils/ndptool.c
+++ b/utils/ndptool.c
@@ -135,6 +135,7 @@ static void print_help(const char *argv0) {
"\t-v --verbose Increase output verbosity\n"
"\t-t --msg-type=TYPE Specify message type\n"
"\t (\"rs\", \"ra\", \"ns\", \"na\")\n"
+ "\t-T --target=TARGET Target address for NS or NA\n"
"\t-i --ifname=IFNAME Specify interface name\n"
"\t-U --unsolicited Send Unsolicited NA\n"
"Available commands:\n"
@@ -333,7 +334,7 @@ static int run_cmd_monitor(struct ndp *ndp, enum ndp_msg_type msg_type,
}
static int run_cmd_send(struct ndp *ndp, enum ndp_msg_type msg_type,
- uint32_t ifindex)
+ uint32_t ifindex, struct in6_addr *target)
{
struct ndp_msg *msg;
int err;
@@ -344,6 +345,8 @@ static int run_cmd_send(struct ndp *ndp, enum ndp_msg_type msg_type,
return err;
}
ndp_msg_ifindex_set(msg, ifindex);
+ ndp_msg_target_set(msg, target);
+ ndp_msg_opt_set(msg);
err = ndp_msg_send_with_flags(ndp, msg, flags);
if (err) {
@@ -384,6 +387,7 @@ int main(int argc, char **argv)
{ "verbose", no_argument, NULL, 'v' },
{ "msg-type", required_argument, NULL, 't' },
{ "ifname", required_argument, NULL, 'i' },
+ { "target", required_argument, NULL, 'T' },
{ "unsolicited",no_argument, NULL, 'U' },
{ NULL, 0, NULL, 0 }
};
@@ -392,12 +396,14 @@ int main(int argc, char **argv)
char *msgtypestr = NULL;
enum ndp_msg_type msg_type;
char *ifname = NULL;
+ char *addr = NULL;
+ struct in6_addr target = IN6ADDR_ANY_INIT;
uint32_t ifindex;
char *cmd_name;
int err;
int res = EXIT_FAILURE;
- while ((opt = getopt_long(argc, argv, "hvt:i:U",
+ while ((opt = getopt_long(argc, argv, "hvt:T:i:U",
long_options, NULL)) >= 0) {
switch(opt) {
@@ -415,6 +421,10 @@ int main(int argc, char **argv)
free(ifname);
ifname = strdup(optarg);
break;
+ case 'd':
+ free(addr);
+ addr = strdup(optarg);
+ break;
case 'U':
flags |= ND_OPT_NA_UNSOL;
break;
@@ -448,6 +458,11 @@ int main(int argc, char **argv)
}
}
+ if (addr && inet_pton(AF_INET6, addr, &target) <= 0) {
+ pr_err("Invalid target address \"%s\"\n", addr);
+ goto errout;
+ }
+
err = get_msg_type(&msg_type, msgtypestr);
if (err) {
pr_err("Invalid message type \"%s\" selected\n", msgtypestr);
@@ -478,7 +493,7 @@ int main(int argc, char **argv)
print_help(argv0);
goto errout;
}
- err = run_cmd_send(ndp, msg_type, ifindex);
+ err = run_cmd_send(ndp, msg_type, ifindex, &target);
} else {
pr_err("Unknown command \"%s\"\n", cmd_name);
goto ndp_close;
--
2.19.2