On Wed, May 29, 2019 at 9:04 PM David Ahern <dsah...@kernel.org> wrote:
>
> From: David Ahern <dsah...@gmail.com>
>
> Add nexthop subcommand to ip. Implement basic commands for creating,
> deleting and dumping nexthop objects. Syntax follows 'nexthop' syntax
> from existing 'ip route' command.
>
> Signed-off-by: David Ahern <dsah...@gmail.com>
If you are re-spinning, request you to pls add a usage example in the
commit msg...or in the man-page.
> ---
> ip/Makefile | 3 +-
> ip/ip.c | 3 +-
> ip/ip_common.h | 2 +
> ip/ipnexthop.c | 571
> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 577 insertions(+), 2 deletions(-)
> create mode 100644 ip/ipnexthop.c
>
> diff --git a/ip/Makefile b/ip/Makefile
> index 7ce6e91a528c..5ab78d7d3b84 100644
> --- a/ip/Makefile
> +++ b/ip/Makefile
> @@ -10,7 +10,8 @@ IPOBJ=ip.o ipaddress.o ipaddrlabel.o iproute.o iprule.o
> ipnetns.o \
> link_iptnl.o link_gre6.o iplink_bond.o iplink_bond_slave.o iplink_hsr.o \
> iplink_bridge.o iplink_bridge_slave.o ipfou.o iplink_ipvlan.o \
> iplink_geneve.o iplink_vrf.o iproute_lwtunnel.o ipmacsec.o ipila.o \
> - ipvrf.o iplink_xstats.o ipseg6.o iplink_netdevsim.o iplink_rmnet.o
> + ipvrf.o iplink_xstats.o ipseg6.o iplink_netdevsim.o iplink_rmnet.o \
> + ipnexthop.o
>
> RTMONOBJ=rtmon.o
>
> diff --git a/ip/ip.c b/ip/ip.c
> index b71ae816e24d..b46fd8dd056c 100644
> --- a/ip/ip.c
> +++ b/ip/ip.c
> @@ -50,7 +50,7 @@ static void usage(void)
> "where OBJECT := { link | address | addrlabel | route | rule
> | neigh | ntable |\n"
> " tunnel | tuntap | maddress | mroute |
> mrule | monitor | xfrm |\n"
> " netns | l2tp | fou | macsec | tcp_metrics
> | token | netconf | ila |\n"
> - " vrf | sr }\n"
> + " vrf | sr | nexthop }\n"
> " OPTIONS := { -V[ersion] | -s[tatistics] | -d[etails]
> | -r[esolve] |\n"
> " -h[uman-readable] | -iec | -j[son] |
> -p[retty] |\n"
> " -f[amily] { inet | inet6 | mpls | bridge
> | link } |\n"
> @@ -100,6 +100,7 @@ static const struct cmd {
> { "netconf", do_ipnetconf },
> { "vrf", do_ipvrf},
> { "sr", do_seg6 },
> + { "nexthop", do_ipnh },
> { "help", do_help },
> { 0 }
> };
> diff --git a/ip/ip_common.h b/ip/ip_common.h
> index 1c90770be548..5f73247ac488 100644
> --- a/ip/ip_common.h
> +++ b/ip/ip_common.h
> @@ -47,6 +47,7 @@ int print_prefix(struct nlmsghdr *n, void *arg);
> int print_rule(struct nlmsghdr *n, void *arg);
> int print_netconf(struct rtnl_ctrl_data *ctrl,
> struct nlmsghdr *n, void *arg);
> +int print_nexthop(struct nlmsghdr *n, void *arg);
> void netns_map_init(void);
> void netns_nsid_socket_init(void);
> int print_nsid(struct nlmsghdr *n, void *arg);
> @@ -80,6 +81,7 @@ int do_ipvrf(int argc, char **argv);
> void vrf_reset(void);
> int netns_identify_pid(const char *pidstr, char *name, int len);
> int do_seg6(int argc, char **argv);
> +int do_ipnh(int argc, char **argv);
>
> int iplink_get(char *name, __u32 filt_mask);
> int iplink_ifla_xstats(int argc, char **argv);
> diff --git a/ip/ipnexthop.c b/ip/ipnexthop.c
> new file mode 100644
> index 000000000000..84c2f01d7309
> --- /dev/null
> +++ b/ip/ipnexthop.c
> @@ -0,0 +1,571 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * ip nexthop
> + *
> + * Copyright (c) 2017-19 Cumulus Networks
> + * Copyright (c) 2017-19 David Ahern <dsah...@gmail.com>
> + */
> +
> +#include <linux/nexthop.h>
> +#include <stdio.h>
> +#include <string.h>
> +#include <rt_names.h>
> +#include <errno.h>
> +
> +#include "utils.h"
> +#include "ip_common.h"
> +
> +static struct
> +{
> + unsigned int flushed;
> + unsigned int groups;
> + unsigned int ifindex;
> + unsigned int master;
> + char *flushb;
> + int flushp;
> + int flushe;
> +} filter;
> +
> +enum {
> + IPNH_LIST,
> + IPNH_FLUSH,
> +};
> +
> +#define RTM_NHA(h) ((struct rtattr *)(((char *)(h)) + \
> + NLMSG_ALIGN(sizeof(struct nhmsg))))
> +
> +static void usage(void) __attribute__((noreturn));
> +
> +static void usage(void)
> +{
> + fprintf(stderr,
> + "Usage: ip nexthop { list | flush } SELECTOR\n"
> + " ip nexthop get id ID\n"
> + " ip nexthop { add | replace } NH\n"
> + " ip nexthop del id ID\n"
> + "SELECTOR := [ id ID ] [ dev DEV ] [ vrf NAME ] [ master DEV
> ] [ groups ]\n"
> + "NH := [ id ID ] [ via [ FAMILY ] ADDRESS ] [ dev DEV ]\n"
> + " [ group <id[,weight]>[/<id[,weight]>/...] ] [ NHFLAGS
> ]\n"
> + " [ encap ENCAPTYPE ENCAPHDR ]\n"
> + "NHFLAGS := [ onlink ]\n");
> + exit(-1);
> +}
> +
> +static int nh_dump_filter(struct nlmsghdr *nlh, int reqlen)
> +{
> + int err;
> +
> + if (filter.ifindex) {
> + err = addattr32(nlh, reqlen, NHA_OIF, filter.ifindex);
> + if (err)
> + return err;
> + }
> +
> + if (filter.groups) {
> + addattr_l(nlh, reqlen, NHA_GROUPS, NULL, 0);
> + if (err)
> + return err;
> + }
> +
> + if (filter.master) {
> + addattr32(nlh, reqlen, NHA_MASTER, filter.master);
> + if (err)
> + return err;
> + }
> +
> + return 0;
> +}
> +
> +struct rtnl_handle rth_del = { .fd = -1 };
> +
> +static int delete_nexthop(__u32 id)
> +{
> + struct {
> + struct nlmsghdr n;
> + struct nhmsg nhm;
> + char buf[64];
> + } req = {
> + .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct nhmsg)),
> + .n.nlmsg_flags = NLM_F_REQUEST,
> + .n.nlmsg_type = RTM_DELNEXTHOP,
> + .nhm.nh_family = AF_UNSPEC,
> + };
> +
> + req.n.nlmsg_seq = ++rth_del.seq;
> +
> + addattr32(&req.n, sizeof(req), NHA_ID, id);
> +
> + if (rtnl_talk(&rth_del, &req.n, NULL) < 0)
> + return -1;
> + return 0;
> +}
> +
> +static int flush_nexthop(struct nlmsghdr *nlh, void *arg)
> +{
> + struct nhmsg *nhm = NLMSG_DATA(nlh);
> + struct rtattr *tb[NHA_MAX+1];
> + __u32 id = 0;
> + int len;
> +
> + len = nlh->nlmsg_len - NLMSG_SPACE(sizeof(*nhm));
> + if (len < 0) {
> + fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
> + return -1;
> + }
> +
> + parse_rtattr(tb, NHA_MAX, RTM_NHA(nhm), len);
> + if (tb[NHA_ID])
> + id = rta_getattr_u32(tb[NHA_ID]);
> +
> + if (id && !delete_nexthop(id))
> + filter.flushed++;
> +
> + return 0;
> +}
> +
> +static int ipnh_flush(unsigned int all)
> +{
> + int rc = -2;
> +
> + if (all) {
> + filter.groups = 1;
> + filter.ifindex = 0;
> + filter.master = 0;
> + }
> +
> + if (rtnl_open(&rth_del, 0) < 0) {
> + fprintf(stderr, "Cannot open rtnetlink\n");
> + return EXIT_FAILURE;
> + }
> +again:
> + if (rtnl_nexthopdump_req(&rth, preferred_family, nh_dump_filter) < 0)
> {
> + perror("Cannot send dump request");
> + goto out;
> + }
> +
> + if (rtnl_dump_filter(&rth, flush_nexthop, stdout) < 0) {
> + fprintf(stderr, "Dump terminated\n");
> + goto out;
> + }
> +
> + /* if deleting all, then remove groups first */
> + if (all && filter.groups) {
> + filter.groups = 0;
> + goto again;
> + }
> +
> + rc = 0;
> +out:
> + rtnl_close(&rth_del);
> + if (!filter.flushed)
> + printf("Nothing to flush\n");
> + else
> + printf("Flushed %d nexthops\n", filter.flushed);
> +
> + return rc;
> +}
> +
> +static void print_nh_group(FILE *fp, const struct rtattr *grps_attr)
> +{
> + struct nexthop_grp *nhg = RTA_DATA(grps_attr);
> + int num = RTA_PAYLOAD(grps_attr) / sizeof(*nhg);
> + int i;
> +
> + if (!num || num * sizeof(*nhg) != RTA_PAYLOAD(grps_attr)) {
> + fprintf(fp, "<invalid nexthop group>");
> + return;
> + }
> +
> + open_json_array(PRINT_JSON, "group");
> + print_string(PRINT_FP, NULL, "%s", "group ");
> + for (i = 0; i < num; ++i) {
> + open_json_object(NULL);
> +
> + if (i)
> + print_string(PRINT_FP, NULL, "%s", "/");
> +
> + print_uint(PRINT_ANY, "id", "%u", nhg[i].id);
> + if (nhg[i].weight)
> + print_uint(PRINT_ANY, "weight", ",%u", nhg[i].weight);
> +
> + close_json_object();
> + }
> + close_json_array(PRINT_JSON, NULL);
> +}
> +
> +static void print_nh_gateway(FILE *fp, const struct nhmsg *nhm,
> + const struct rtattr *rta)
> +{
> + const char *gateway = format_host_rta(nhm->nh_family, rta);
> +
> + if (is_json_context())
> + print_string(PRINT_JSON, "gateway", NULL, gateway);
> + else {
> + fprintf(fp, "via ");
> + print_color_string(PRINT_FP, ifa_family_color(nhm->nh_family),
> + NULL, "%s ", gateway);
> + }
> +}
> +
> +int print_nexthop(struct nlmsghdr *n, void *arg)
> +{
> + struct nhmsg *nhm = NLMSG_DATA(n);
> + struct rtattr *tb[NHA_MAX+1];
> + FILE *fp = (FILE *)arg;
> + int len;
> +
> + SPRINT_BUF(b1);
> +
> + if (n->nlmsg_type != RTM_DELNEXTHOP &&
> + n->nlmsg_type != RTM_NEWNEXTHOP) {
> + fprintf(stderr, "Not a nexthop: %08x %08x %08x\n",
> + n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
> + return -1;
> + }
> +
> + len = n->nlmsg_len - NLMSG_SPACE(sizeof(*nhm));
> + if (len < 0) {
> + close_json_object();
> + fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
> + return -1;
> + }
> +
> + parse_rtattr(tb, NHA_MAX, RTM_NHA(nhm), len);
> +
> + open_json_object(NULL);
> +
> + if (n->nlmsg_type == RTM_DELROUTE)
> + print_bool(PRINT_ANY, "deleted", "Deleted ", true);
> +
> + if (tb[NHA_ID])
> + print_uint(PRINT_ANY, "id", "id %u ",
> + rta_getattr_u32(tb[NHA_ID]));
> +
> + if (tb[NHA_GROUP])
> + print_nh_group(fp, tb[NHA_GROUP]);
> +
> + if (tb[NHA_ENCAP])
> + lwt_print_encap(fp, tb[NHA_ENCAP_TYPE], tb[NHA_ENCAP]);
> +
> + if (tb[NHA_GATEWAY])
> + print_nh_gateway(fp, nhm, tb[NHA_GATEWAY]);
> +
> + if (tb[NHA_OIF])
> + print_rta_if(fp, tb[NHA_OIF], "dev");
> +
> + if (nhm->nh_scope != RT_SCOPE_UNIVERSE || show_details > 0) {
> + print_string(PRINT_ANY, "scope", "scope %s ",
> + rtnl_rtscope_n2a(nhm->nh_scope, b1, sizeof(b1)));
> + }
> +
> + if (tb[NHA_BLACKHOLE])
> + print_null(PRINT_ANY, "blackhole", "blackhole", NULL);
> +
> + if (nhm->nh_protocol != RTPROT_UNSPEC || show_details > 0) {
> + print_string(PRINT_ANY, "protocol", "proto %s ",
> + rtnl_rtprot_n2a(nhm->nh_protocol, b1,
> sizeof(b1)));
> + }
> +
> + if (tb[NHA_OIF])
> + print_rt_flags(fp, nhm->nh_flags);
> +
> + print_string(PRINT_FP, NULL, "%s", "\n");
> + close_json_object();
> + fflush(fp);
> +
> + return 0;
> +}
> +
> +static int add_nh_group_attr(struct nlmsghdr *n, int maxlen, char *argv)
> +{
> + struct nexthop_grp *grps;
> + int count = 0, i;
> + char *sep, *wsep;
> +
> + if (*argv != '\0')
> + count = 1;
> +
> + /* separator is '/' */
> + sep = strchr(argv, '/');
> + while (sep) {
> + count++;
> + sep = strchr(sep + 1, '/');
> + }
> +
> + if (count == 0)
> + return -1;
> +
> + grps = calloc(count, sizeof(*grps));
> + if (!grps)
> + return -1;
> +
> + for (i = 0; i < count; ++i) {
> + sep = strchr(argv, '/');
> + if (sep)
> + *sep = '\0';
> +
> + wsep = strchr(argv, ',');
> + if (wsep)
> + *wsep = '\0';
> +
> + if (get_unsigned(&grps[i].id, argv, 0))
> + return -1;
> + if (wsep) {
> + unsigned int tmp;
> +
> + wsep++;
> + if (get_unsigned(&tmp, wsep, 0))
> + return -1;
> + if (tmp > 254)
> + return -1;
> + grps[i].weight = tmp;
> + }
> +
> + if (!sep)
> + break;
> +
> + argv = sep + 1;
> + }
> +
> + return addattr_l(n, maxlen, NHA_GROUP, grps, count * sizeof(*grps));
> +}
> +
> +static int ipnh_modify(int cmd, unsigned int flags, int argc, char **argv)
> +{
> + struct {
> + struct nlmsghdr n;
> + struct nhmsg nhm;
> + char buf[1024];
> + } req = {
> + .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct nhmsg)),
> + .n.nlmsg_flags = NLM_F_REQUEST | flags,
> + .n.nlmsg_type = cmd,
> + .nhm.nh_family = preferred_family,
> + };
> + __u32 nh_flags = 0;
> +
> + while (argc > 0) {
> + if (!strcmp(*argv, "id")) {
> + __u32 id;
> +
> + NEXT_ARG();
> + if (get_unsigned(&id, *argv, 0))
> + invarg("invalid id value", *argv);
> + addattr32(&req.n, sizeof(req), NHA_ID, id);
> + } else if (!strcmp(*argv, "dev")) {
> + int ifindex;
> +
> + NEXT_ARG();
> + ifindex = ll_name_to_index(*argv);
> + if (!ifindex)
> + invarg("Device does not exist\n", *argv);
> + addattr32(&req.n, sizeof(req), NHA_OIF, ifindex);
> + if (req.nhm.nh_family == AF_UNSPEC)
> + req.nhm.nh_family = AF_INET;
> + } else if (strcmp(*argv, "via") == 0) {
> + inet_prefix addr;
> + int family;
> +
> + NEXT_ARG();
> + family = read_family(*argv);
> + if (family == AF_UNSPEC)
> + family = req.nhm.nh_family;
> + else
> + NEXT_ARG();
> + get_addr(&addr, *argv, family);
> + if (req.nhm.nh_family == AF_UNSPEC)
> + req.nhm.nh_family = addr.family;
> + else if (req.nhm.nh_family != addr.family)
> + invarg("address family mismatch\n", *argv);
> + addattr_l(&req.n, sizeof(req), NHA_GATEWAY,
> + &addr.data, addr.bytelen);
> + } else if (strcmp(*argv, "encap") == 0) {
> + char buf[1024];
> + struct rtattr *rta = (void *)buf;
> +
> + rta->rta_type = NHA_ENCAP;
> + rta->rta_len = RTA_LENGTH(0);
> +
> + lwt_parse_encap(rta, sizeof(buf), &argc, &argv,
> + NHA_ENCAP, NHA_ENCAP_TYPE);
> +
> + if (rta->rta_len > RTA_LENGTH(0)) {
> + addraw_l(&req.n, 1024, RTA_DATA(rta),
> + RTA_PAYLOAD(rta));
> + }
> + } else if (!strcmp(*argv, "blackhole")) {
> + addattr_l(&req.n, sizeof(req), NHA_BLACKHOLE, NULL,
> 0);
> + if (req.nhm.nh_family == AF_UNSPEC)
> + req.nhm.nh_family = AF_INET;
> + } else if (!strcmp(*argv, "onlink")) {
> + nh_flags |= RTNH_F_ONLINK;
> + } else if (!strcmp(*argv, "group")) {
> + NEXT_ARG();
> +
> + if (add_nh_group_attr(&req.n, sizeof(req), *argv))
> + invarg("\"group\" value is invalid\n", *argv);
> + } else if (strcmp(*argv, "help") == 0) {
> + usage();
> + } else {
> + invarg("", *argv);
> + }
> + argc--; argv++;
> + }
> +
> + req.nhm.nh_flags = nh_flags;
> +
> + if (rtnl_talk(&rth, &req.n, NULL) < 0)
> + return -2;
> +
> + return 0;
> +}
> +
> +static int ipnh_get_id(__u32 id)
> +{
> + struct {
> + struct nlmsghdr n;
> + struct nhmsg nhm;
> + char buf[1024];
> + } req = {
> + .n.nlmsg_len = NLMSG_LENGTH(sizeof(struct nhmsg)),
> + .n.nlmsg_flags = NLM_F_REQUEST,
> + .n.nlmsg_type = RTM_GETNEXTHOP,
> + .nhm.nh_family = preferred_family,
> + };
> + struct nlmsghdr *answer;
> +
> + addattr32(&req.n, sizeof(req), NHA_ID, id);
> +
> + if (rtnl_talk(&rth, &req.n, &answer) < 0)
> + return -2;
> +
> + new_json_obj(json);
> +
> + if (print_nexthop(answer, (void *)stdout) < 0) {
> + free(answer);
> + return -1;
> + }
> +
> + delete_json_obj();
> + fflush(stdout);
> +
> + free(answer);
> +
> + return 0;
> +}
> +
> +static int ipnh_list_flush(int argc, char **argv, int action)
> +{
> + unsigned int all = (argc == 0);
> +
> + while (argc > 0) {
> + if (!matches(*argv, "dev")) {
> + NEXT_ARG();
> + filter.ifindex = ll_name_to_index(*argv);
> + if (!filter.ifindex)
> + invarg("Device does not exist\n", *argv);
> + } else if (!matches(*argv, "groups")) {
> + filter.groups = 1;
> + } else if (!matches(*argv, "master")) {
> + NEXT_ARG();
> + filter.master = ll_name_to_index(*argv);
> + if (!filter.master)
> + invarg("Device does not exist\n", *argv);
> + } else if (matches(*argv, "vrf") == 0) {
> + NEXT_ARG();
> + if (!name_is_vrf(*argv))
> + invarg("Invalid VRF\n", *argv);
> + filter.master = ll_name_to_index(*argv);
> + if (!filter.master)
> + invarg("VRF does not exist\n", *argv);
> + } else if (!strcmp(*argv, "id")) {
> + __u32 id;
> +
> + NEXT_ARG();
> + if (get_unsigned(&id, *argv, 0))
> + invarg("invalid id value", *argv);
> + return ipnh_get_id(id);
> + } else if (matches(*argv, "help") == 0) {
> + usage();
> + } else {
> + invarg("", *argv);
> + }
> + argc--; argv++;
> + }
> +
> + if (action == IPNH_FLUSH)
> + return ipnh_flush(all);
> +
> + if (rtnl_nexthopdump_req(&rth, preferred_family, nh_dump_filter) < 0)
> {
> + perror("Cannot send dump request");
> + return -2;
> + }
> +
> + new_json_obj(json);
> +
> + if (rtnl_dump_filter(&rth, print_nexthop, stdout) < 0) {
> + fprintf(stderr, "Dump terminated\n");
> + return -2;
> + }
> +
> + delete_json_obj();
> + fflush(stdout);
> +
> + return 0;
> +}
> +
> +static int ipnh_get(int argc, char **argv)
> +{
> + __u32 id = 0;
> +
> + while (argc > 0) {
> + if (!strcmp(*argv, "id")) {
> + NEXT_ARG();
> + if (get_unsigned(&id, *argv, 0))
> + invarg("invalid id value", *argv);
> + } else {
> + usage();
> + }
> + argc--; argv++;
> + }
> +
> + if (!id) {
> + usage();
> + return -1;
> + }
> +
> + return ipnh_get_id(id);
> +}
> +
> +int do_ipnh(int argc, char **argv)
> +{
> + if (argc < 1)
> + return ipnh_list_flush(0, NULL, IPNH_LIST);
> +
> + if (!matches(*argv, "add"))
> + return ipnh_modify(RTM_NEWNEXTHOP, NLM_F_CREATE|NLM_F_EXCL,
> + argc-1, argv+1);
> + if (!matches(*argv, "replace"))
> + return ipnh_modify(RTM_NEWNEXTHOP, NLM_F_CREATE|NLM_F_REPLACE,
> + argc-1, argv+1);
> + if (!matches(*argv, "delete"))
> + return ipnh_modify(RTM_DELNEXTHOP, 0, argc-1, argv+1);
> +
> + if (!matches(*argv, "list") ||
> + !matches(*argv, "show") ||
> + !matches(*argv, "lst"))
> + return ipnh_list_flush(argc-1, argv+1, IPNH_LIST);
> +
> + if (!matches(*argv, "get"))
> + return ipnh_get(argc-1, argv+1);
> +
> + if (!matches(*argv, "flush"))
> + return ipnh_list_flush(argc-1, argv+1, IPNH_FLUSH);
> +
> + if (!matches(*argv, "help"))
> + usage();
> +
> + fprintf(stderr,
> + "Command \"%s\" is unknown, try \"ip nexthop help\".\n",
> *argv);
> + exit(-1);
> +}
> --
> 2.11.0
>
