/*

 * ipneigh.c		"ip neigh".

 *

 *		This program is free software; you can redistribute it and/or

 *		modify it under the terms of the GNU General Public License

 *		as published by the Free Software Foundation; either version

 *		2 of the License, or (at your option) any later version.

 *

 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>

 *

 */

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <fcntl.h>

#include <string.h>

#include <sys/time.h>

#include <sys/socket.h>

#include <netinet/in.h>

#include <netinet/ip.h>

#include "rt_names.h"

#include "utils.h"

#include "ip_common.h"

#include "json_print.h"

#define NUD_VALID	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)

#define MAX_ROUNDS	10

static struct

{

	int family;

	int index;

	int state;

	int unused_only;

	inet_prefix pfx;

	int flushed;

	char *flushb;

	int flushp;

	int flushe;

	int master;

	int protocol;

	__u8 ndm_flags;

} filter;

static void usage(void) __attribute__((noreturn));

static void usage(void)

{

	fprintf(stderr,

		"Usage: ip neigh { add | del | change | replace }\n"

		"		{ ADDR [ lladdr LLADDR ] [ nud STATE ] | proxy ADDR } [ dev DEV ]\n"

		"		[ router ] [ extern_learn ] [ protocol PROTO ]\n"

		"\n"

		"	ip neigh { show | flush } [ proxy ] [ to PREFIX ] [ dev DEV ] [ nud STATE ]\n"

		"				  [ vrf NAME ]\n"

		"	ip neigh get { ADDR | proxy ADDR } dev DEV\n"

		"\n"

		"STATE := { permanent | noarp | stale | reachable | none |\n"

		"           incomplete | delay | probe | failed }\n");

	exit(-1);

}

static int nud_state_a2n(unsigned int *state, const char *arg)

{

	if (matches(arg, "permanent") == 0)

		*state = NUD_PERMANENT;

	else if (matches(arg, "reachable") == 0)

		*state = NUD_REACHABLE;

	else if (strcmp(arg, "noarp") == 0)

		*state = NUD_NOARP;

	else if (strcmp(arg, "none") == 0)

		*state = NUD_NONE;

	else if (strcmp(arg, "stale") == 0)

		*state = NUD_STALE;

	else if (strcmp(arg, "incomplete") == 0)

		*state = NUD_INCOMPLETE;

	else if (strcmp(arg, "delay") == 0)

		*state = NUD_DELAY;

	else if (strcmp(arg, "probe") == 0)

		*state = NUD_PROBE;

	else if (matches(arg, "failed") == 0)

		*state = NUD_FAILED;

	else {

		if (get_unsigned(state, arg, 0))

			return -1;

		if (*state >= 0x100 || (*state&((*state)-1)))

			return -1;

	}

	return 0;

}

static int flush_update(void)

{

	if (rtnl_send_check(&rth, filter.flushb, filter.flushp) < 0) {

		perror("Failed to send flush request");

		return -1;

	}

	filter.flushp = 0;

	return 0;

}

static int ipneigh_modify(int cmd, int flags, int argc, char **argv)

{

	struct {

		struct nlmsghdr	n;

		struct ndmsg		ndm;

		char			buf[256];

	} req = {

		.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),

		.n.nlmsg_flags = NLM_F_REQUEST | flags,

		.n.nlmsg_type = cmd,

		.ndm.ndm_family = preferred_family,

		.ndm.ndm_state = NUD_PERMANENT,

	};

	char  *dev = NULL;

	int dst_ok = 0;

	int dev_ok = 0;

	int lladdr_ok = 0;

	char *lla = NULL;

	inet_prefix dst;

	while (argc > 0) {

		if (matches(*argv, "lladdr") == 0) {

			NEXT_ARG();

			if (lladdr_ok)

				duparg("lladdr", *argv);

			lla = *argv;

			lladdr_ok = 1;

		} else if (strcmp(*argv, "nud") == 0) {

			unsigned int state;

			NEXT_ARG();

			if (nud_state_a2n(&state, *argv))

				invarg("nud state is bad", *argv);

			req.ndm.ndm_state = state;

		} else if (matches(*argv, "proxy") == 0) {

			NEXT_ARG();

			if (matches(*argv, "help") == 0)

				usage();

			if (dst_ok)

				duparg("address", *argv);

			get_addr(&dst, *argv, preferred_family);

			dst_ok = 1;

			dev_ok = 1;

			req.ndm.ndm_flags |= NTF_PROXY;

		} else if (strcmp(*argv, "router") == 0) {

			req.ndm.ndm_flags |= NTF_ROUTER;

		} else if (matches(*argv, "extern_learn") == 0) {

			req.ndm.ndm_flags |= NTF_EXT_LEARNED;

		} else if (strcmp(*argv, "dev") == 0) {

			NEXT_ARG();

			dev = *argv;

			dev_ok = 1;

		} else if (matches(*argv, "protocol") == 0) {

			__u32 proto;

			NEXT_ARG();

			if (rtnl_rtprot_a2n(&proto, *argv))

				invarg("\"protocol\" value is invalid\n", *argv);

			if (addattr8(&req.n, sizeof(req), NDA_PROTOCOL, proto))

				return -1;

		} else {

			if (strcmp(*argv, "to") == 0) {

				NEXT_ARG();

			}

			if (matches(*argv, "help") == 0) {

				NEXT_ARG();

			}

			if (dst_ok)

				duparg2("to", *argv);

			get_addr(&dst, *argv, preferred_family);

			dst_ok = 1;

		}

		argc--; argv++;

	}

	if (!dev_ok || !dst_ok || dst.family == AF_UNSPEC) {

		fprintf(stderr, "Device and destination are required arguments.\n");

		exit(-1);

	}

	req.ndm.ndm_family = dst.family;

	if (addattr_l(&req.n, sizeof(req), NDA_DST, &dst.data, dst.bytelen) < 0)

		return -1;

	if (lla && strcmp(lla, "null")) {

		char llabuf[20];

		int l;

		l = ll_addr_a2n(llabuf, sizeof(llabuf), lla);

		if (l < 0)

			return -1;

		if (addattr_l(&req.n, sizeof(req), NDA_LLADDR, llabuf, l) < 0)

			return -1;

	}

	ll_init_map(&rth);

	if (dev) {

		req.ndm.ndm_ifindex = ll_name_to_index(dev);

		if (!req.ndm.ndm_ifindex)

			return nodev(dev);

	}

	if (rtnl_talk(&rth, &req.n, NULL) < 0)

		exit(2);

	return 0;

}

static void print_cacheinfo(const struct nda_cacheinfo *ci)

{

	static int hz;

	if (!hz)

		hz = get_user_hz();

	if (ci->ndm_refcnt)

		print_uint(PRINT_ANY, "refcnt",

				" ref %u", ci->ndm_refcnt);

	print_uint(PRINT_ANY, "used", " used %u", ci->ndm_used / hz);

	print_uint(PRINT_ANY, "confirmed", "/%u", ci->ndm_confirmed / hz);

	print_uint(PRINT_ANY, "updated", "/%u", ci->ndm_updated / hz);

}

static void print_neigh_state(unsigned int nud)

{

	open_json_array(PRINT_JSON,

			is_json_context() ?  "state" : "");

#define PRINT_FLAG(f)						\

	if (nud & NUD_##f) {					\

		nud &= ~NUD_##f;				\

		print_string(PRINT_ANY, NULL, " %s", #f);	\

	}

	PRINT_FLAG(INCOMPLETE);

	PRINT_FLAG(REACHABLE);

	PRINT_FLAG(STALE);

	PRINT_FLAG(DELAY);

	PRINT_FLAG(PROBE);

	PRINT_FLAG(FAILED);

	PRINT_FLAG(NOARP);

	PRINT_FLAG(PERMANENT);

#undef PRINT_FLAG

	close_json_array(PRINT_JSON, NULL);

}

int print_neigh(struct nlmsghdr *n, void *arg)

{

	FILE *fp = (FILE *)arg;

	struct ndmsg *r = NLMSG_DATA(n);

	int len = n->nlmsg_len;

	struct rtattr *tb[NDA_MAX+1];

	static int logit = 1;

	__u8 protocol = 0;

	if (n->nlmsg_type != RTM_NEWNEIGH && n->nlmsg_type != RTM_DELNEIGH &&

	    n->nlmsg_type != RTM_GETNEIGH) {

		fprintf(stderr, "Not RTM_NEWNEIGH: %08x %08x %08x\n",

			n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);

		return 0;

	}

	len -= NLMSG_LENGTH(sizeof(*r));

	if (len < 0) {

		fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);

		return -1;

	}

	if (filter.flushb && n->nlmsg_type != RTM_NEWNEIGH)

		return 0;

	if (filter.family && filter.family != r->ndm_family)

		return 0;

	if (filter.index && filter.index != r->ndm_ifindex)

		return 0;

	if (!(filter.state&r->ndm_state) &&

	    !(r->ndm_flags & NTF_PROXY) &&

	    !(r->ndm_flags & NTF_EXT_LEARNED) &&

	    (r->ndm_state || !(filter.state&0x100)) &&

	    (r->ndm_family != AF_DECnet))

		return 0;

	if (filter.master && !(n->nlmsg_flags & NLM_F_DUMP_FILTERED)) {

		if (logit) {

			logit = 0;

			fprintf(fp,

				"\nWARNING: Kernel does not support filtering by master device\n\n");

		}

	}

	parse_rtattr(tb, NDA_MAX, NDA_RTA(r), n->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));

	if (inet_addr_match_rta(&filter.pfx, tb[NDA_DST]))

		return 0;

	if (tb[NDA_PROTOCOL])

		protocol = rta_getattr_u8(tb[NDA_PROTOCOL]);

	if (filter.protocol && filter.protocol != protocol)

		return 0;

	if (filter.unused_only && tb[NDA_CACHEINFO]) {

		struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);

		if (ci->ndm_refcnt)

			return 0;

	}

	if (filter.flushb) {

		struct nlmsghdr *fn;

		if (NLMSG_ALIGN(filter.flushp) + n->nlmsg_len > filter.flushe) {

			if (flush_update())

				return -1;

		}

		fn = (struct nlmsghdr *)(filter.flushb + NLMSG_ALIGN(filter.flushp));

		memcpy(fn, n, n->nlmsg_len);

		fn->nlmsg_type = RTM_DELNEIGH;

		fn->nlmsg_flags = NLM_F_REQUEST;

		fn->nlmsg_seq = ++rth.seq;

		filter.flushp = (((char *)fn) + n->nlmsg_len) - filter.flushb;

		filter.flushed++;

		if (show_stats < 2)

			return 0;

	}

	open_json_object(NULL);

	if (n->nlmsg_type == RTM_DELNEIGH)

		print_bool(PRINT_ANY, "deleted", "Deleted ", true);

	else if (n->nlmsg_type == RTM_GETNEIGH)

		print_null(PRINT_ANY, "miss", "%s ", "miss");

	if (tb[NDA_DST]) {

		const char *dst;

		int family = r->ndm_family;

		if (family == AF_BRIDGE) {

			if (RTA_PAYLOAD(tb[NDA_DST]) == sizeof(struct in6_addr))

				family = AF_INET6;

			else

				family = AF_INET;

		}

		dst = format_host_rta(family, tb[NDA_DST]);

		print_color_string(PRINT_ANY,

				   ifa_family_color(family),

				   "dst", "%s ", dst);

	}

	if (!filter.index && r->ndm_ifindex) {

		if (!is_json_context())

			fprintf(fp, "dev ");

		print_color_string(PRINT_ANY, COLOR_IFNAME,

				   "dev", "%s ",

				   ll_index_to_name(r->ndm_ifindex));

	}

	if (tb[NDA_LLADDR]) {

		const char *lladdr;

		SPRINT_BUF(b1);

		lladdr = ll_addr_n2a(RTA_DATA(tb[NDA_LLADDR]),

				     RTA_PAYLOAD(tb[NDA_LLADDR]),

				     ll_index_to_type(r->ndm_ifindex),

				     b1, sizeof(b1));

		if (!is_json_context())

			fprintf(fp, "lladdr ");

		print_color_string(PRINT_ANY, COLOR_MAC,

				   "lladdr", "%s", lladdr);

	}

	if (r->ndm_flags & NTF_ROUTER)

		print_null(PRINT_ANY, "router", " %s", "router");

	if (r->ndm_flags & NTF_PROXY)

		print_null(PRINT_ANY, "proxy", " %s", "proxy");

	if (r->ndm_flags & NTF_EXT_LEARNED)

		print_null(PRINT_ANY, "extern_learn", " %s ", "extern_learn");

	if (r->ndm_flags & NTF_OFFLOADED)

		print_null(PRINT_ANY, "offload", " %s", "offload");

	if (show_stats) {

		if (tb[NDA_CACHEINFO])

			print_cacheinfo(RTA_DATA(tb[NDA_CACHEINFO]));

		if (tb[NDA_PROBES])

			print_uint(PRINT_ANY, "probes", " probes %u",

				   rta_getattr_u32(tb[NDA_PROBES]));

	}

	if (r->ndm_state)

		print_neigh_state(r->ndm_state);

	if (protocol) {

		SPRINT_BUF(b1);

		print_string(PRINT_ANY, "protocol", " proto %s ",

			     rtnl_rtprot_n2a(protocol, b1, sizeof(b1)));

	}

	print_string(PRINT_FP, NULL, "\n", "");

	close_json_object();

	fflush(stdout);

	return 0;

}

void ipneigh_reset_filter(int ifindex)

{

	memset(&filter, 0, sizeof(filter));

	filter.state = ~0;

	filter.index = ifindex;

}

static int ipneigh_dump_filter(struct nlmsghdr *nlh, int reqlen)

{

	struct ndmsg *ndm = NLMSG_DATA(nlh);

	int err;

	ndm->ndm_flags = filter.ndm_flags;

	if (filter.index) {

		err = addattr32(nlh, reqlen, NDA_IFINDEX, filter.index);

		if (err)

			return err;

	}

	if (filter.master) {

		err = addattr32(nlh, reqlen, NDA_MASTER, filter.master);

		if (err)

			return err;

	}

	return 0;

}

static int do_show_or_flush(int argc, char **argv, int flush)

{

	char *filter_dev = NULL;

	int state_given = 0;

	ipneigh_reset_filter(0);

	if (!filter.family)

		filter.family = preferred_family;

	if (flush) {

		if (argc <= 0) {

			fprintf(stderr, "Flush requires arguments.\n");

			return -1;

		}

		filter.state = ~(NUD_PERMANENT|NUD_NOARP);

	} else

		filter.state = 0xFF & ~NUD_NOARP;

	while (argc > 0) {

		if (strcmp(*argv, "dev") == 0) {

			NEXT_ARG();

			if (filter_dev)

				duparg("dev", *argv);

			filter_dev = *argv;

		} else if (strcmp(*argv, "master") == 0) {

			int ifindex;

			NEXT_ARG();

			ifindex = ll_name_to_index(*argv);

			if (!ifindex)

				invarg("Device does not exist\n", *argv);

			filter.master = ifindex;

		} else if (strcmp(*argv, "vrf") == 0) {

			int ifindex;

			NEXT_ARG();

			ifindex = ll_name_to_index(*argv);

			if (!ifindex)

				invarg("Not a valid VRF name\n", *argv);

			if (!name_is_vrf(*argv))

				invarg("Not a valid VRF name\n", *argv);

			filter.master = ifindex;

		} else if (strcmp(*argv, "unused") == 0) {

			filter.unused_only = 1;

		} else if (strcmp(*argv, "nud") == 0) {

			unsigned int state;

			NEXT_ARG();

			if (!state_given) {

				state_given = 1;

				filter.state = 0;

			}

			if (nud_state_a2n(&state, *argv)) {

				if (strcmp(*argv, "all") != 0)

					invarg("nud state is bad", *argv);

				state = ~0;

				if (flush)

					state &= ~NUD_NOARP;

			}

			if (state == 0)

				state = 0x100;

			filter.state |= state;

		} else if (strcmp(*argv, "proxy") == 0) {

			filter.ndm_flags = NTF_PROXY;

		} else if (matches(*argv, "protocol") == 0) {

			__u32 prot;

			NEXT_ARG();

			if (rtnl_rtprot_a2n(&prot, *argv)) {

				if (strcmp(*argv, "all"))

					invarg("invalid \"protocol\"\n", *argv);

				prot = 0;

			}

			filter.protocol = prot;

		} else {

			if (strcmp(*argv, "to") == 0) {

				NEXT_ARG();

			}

			if (matches(*argv, "help") == 0)

				usage();

			if (get_prefix(&filter.pfx, *argv, filter.family))

				invarg("to value is invalid\n", *argv);

			if (filter.family == AF_UNSPEC)

				filter.family = filter.pfx.family;

		}

		argc--; argv++;

	}

	ll_init_map(&rth);

	if (filter_dev) {

		filter.index = ll_name_to_index(filter_dev);

		if (!filter.index)

			return nodev(filter_dev);

	}

	if (flush) {

		int round = 0;

		char flushb[4096-512];

		filter.flushb = flushb;

		filter.flushp = 0;

		filter.flushe = sizeof(flushb);

		while (round < MAX_ROUNDS) {

			if (rtnl_neighdump_req(&rth, filter.family,

					       ipneigh_dump_filter) < 0) {

				perror("Cannot send dump request");

				exit(1);

			}

			filter.flushed = 0;

			if (rtnl_dump_filter(&rth, print_neigh, stdout) < 0) {

				fprintf(stderr, "Flush terminated\n");

				exit(1);

			}

			if (filter.flushed == 0) {

				if (show_stats) {

					if (round == 0)

						printf("Nothing to flush.\n");

					else

						printf("*** Flush is complete after %d round%s ***\n", round, round > 1?"s":"");

				}

				fflush(stdout);

				return 0;

			}

			round++;

			if (flush_update() < 0)

				exit(1);

			if (show_stats) {

				printf("\n*** Round %d, deleting %d entries ***\n", round, filter.flushed);

				fflush(stdout);

			}

			filter.state &= ~NUD_FAILED;

		}

		printf("*** Flush not complete bailing out after %d rounds\n",

			MAX_ROUNDS);

		return 1;

	}

	if (rtnl_neighdump_req(&rth, filter.family, ipneigh_dump_filter) < 0) {

		perror("Cannot send dump request");

		exit(1);

	}

	new_json_obj(json);

	if (rtnl_dump_filter(&rth, print_neigh, stdout) < 0) {

		fprintf(stderr, "Dump terminated\n");

		exit(1);

	}

	delete_json_obj();

	return 0;

}

static int ipneigh_get(int argc, char **argv)

{

	struct {

		struct nlmsghdr	n;

		struct ndmsg		ndm;

		char			buf[1024];

	} req = {

		.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),

		.n.nlmsg_flags = NLM_F_REQUEST,

		.n.nlmsg_type = RTM_GETNEIGH,

		.ndm.ndm_family = preferred_family,

	};

	struct nlmsghdr *answer;

	char  *d = NULL;

	int dst_ok = 0;

	int dev_ok = 0;

	inet_prefix dst;

	while (argc > 0) {

		if (strcmp(*argv, "dev") == 0) {

			NEXT_ARG();

			d = *argv;

			dev_ok = 1;

		} else if (matches(*argv, "proxy") == 0) {

			NEXT_ARG();

			if (matches(*argv, "help") == 0)

				usage();

			if (dst_ok)

				duparg("address", *argv);

			get_addr(&dst, *argv, preferred_family);

			dst_ok = 1;

			dev_ok = 1;

			req.ndm.ndm_flags |= NTF_PROXY;

		} else {

			if (strcmp(*argv, "to") == 0)

				NEXT_ARG();

			if (matches(*argv, "help") == 0)

				usage();

			if (dst_ok)

				duparg2("to", *argv);

			get_addr(&dst, *argv, preferred_family);

			dst_ok = 1;

		}

		argc--; argv++;

	}

	if (!dev_ok || !dst_ok || dst.family == AF_UNSPEC) {

		fprintf(stderr, "Device and address are required arguments.\n");

		return -1;

	}

	req.ndm.ndm_family = dst.family;

	if (addattr_l(&req.n, sizeof(req), NDA_DST, &dst.data, dst.bytelen) < 0)

		return -1;

	if (d) {

		req.ndm.ndm_ifindex = ll_name_to_index(d);

		if (!req.ndm.ndm_ifindex) {

			fprintf(stderr, "Cannot find device \"%s\"\n", d);

			return -1;

		}

	}

	if (rtnl_talk(&rth, &req.n, &answer) < 0)

		return -2;

	ipneigh_reset_filter(0);

	if (print_neigh(answer, stdout) < 0) {

		fprintf(stderr, "An error :-)\n");

		return -1;

	}

	return 0;

}

int do_ipneigh(int argc, char **argv)

{

	if (argc > 0) {

		if (matches(*argv, "add") == 0)

			return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_EXCL, argc-1, argv+1);

		if (matches(*argv, "change") == 0 ||

		    strcmp(*argv, "chg") == 0)

			return ipneigh_modify(RTM_NEWNEIGH, NLM_F_REPLACE, argc-1, argv+1);

		if (matches(*argv, "replace") == 0)

			return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_REPLACE, argc-1, argv+1);

		if (matches(*argv, "delete") == 0)

			return ipneigh_modify(RTM_DELNEIGH, 0, argc-1, argv+1);

		if (matches(*argv, "get") == 0)

			return ipneigh_get(argc-1, argv+1);

		if (matches(*argv, "show") == 0 ||

		    matches(*argv, "lst") == 0 ||

		    matches(*argv, "list") == 0)

			return do_show_or_flush(argc-1, argv+1, 0);

		if (matches(*argv, "flush") == 0)

			return do_show_or_flush(argc-1, argv+1, 1);

		if (matches(*argv, "help") == 0)

			usage();

	} else

		return do_show_or_flush(0, NULL, 0);

	fprintf(stderr, "Command \"%s\" is unknown, try \"ip neigh help\".\n", *argv);

	exit(-1);

}