[mirror_iproute2.git] / tc / em_ipset.c

/*
 * em_ipset.c		IPset Ematch
 *
 * (C) 2012 Florian Westphal <fw@strlen.de>
 *
 * Parts taken from iptables libxt_set.h:
 * Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
 *                         Patrick Schaaf <bof@bof.de>
 *                         Martin Josefsson <gandalf@wlug.westbo.se>
 * Copyright (C) 2003-2010 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <stdbool.h>
#include <stdio.h>
#include <errno.h>
#include <netdb.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <getopt.h>

#include <xtables.h>
#include <linux/netfilter/ipset/ip_set.h>

#ifndef IPSET_INVALID_ID
typedef __u16 ip_set_id_t;

enum ip_set_dim {
	IPSET_DIM_ZERO = 0,
	IPSET_DIM_ONE,
	IPSET_DIM_TWO,
	IPSET_DIM_THREE,
	IPSET_DIM_MAX = 6,
};
#endif /* IPSET_INVALID_ID */

#include <linux/netfilter/xt_set.h>
#include "m_ematch.h"

#ifndef IPSET_INVALID_ID
#define IPSET_INVALID_ID	65535
#define SO_IP_SET		83

union ip_set_name_index {
	char name[IPSET_MAXNAMELEN];
	__u16 index;
};

#define IP_SET_OP_GET_BYNAME	0x00000006	/* Get set index by name */
struct ip_set_req_get_set {
	unsigned int op;
	unsigned int version;
	union ip_set_name_index set;
};

#define IP_SET_OP_GET_BYINDEX	0x00000007	/* Get set name by index */
/* Uses ip_set_req_get_set */

#define IP_SET_OP_VERSION	0x00000100	/* Ask kernel version */
struct ip_set_req_version {
	unsigned int op;
	unsigned int version;
};
#endif /* IPSET_INVALID_ID */

extern struct ematch_util ipset_ematch_util;

static int get_version(unsigned int *version)
{
	int res, sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
	struct ip_set_req_version req_version;
	socklen_t size = sizeof(req_version);

	if (sockfd < 0) {
		fputs("Can't open socket to ipset.\n", stderr);
		return -1;
	}

	req_version.op = IP_SET_OP_VERSION;
	res = getsockopt(sockfd, SOL_IP, SO_IP_SET, &req_version, &size);
	if (res != 0) {
		perror("xt_set getsockopt");
		close(sockfd);
		return -1;
	}

	*version = req_version.version;
	return sockfd;
}

static int do_getsockopt(struct ip_set_req_get_set *req)
{
	int sockfd, res;
	socklen_t size = sizeof(struct ip_set_req_get_set);

	sockfd = get_version(&req->version);
	if (sockfd < 0)
		return -1;
	res = getsockopt(sockfd, SOL_IP, SO_IP_SET, req, &size);
	if (res != 0)
		perror("Problem when communicating with ipset");
	close(sockfd);
	if (res != 0)
		return -1;

	if (size != sizeof(struct ip_set_req_get_set)) {
		fprintf(stderr,
			"Incorrect return size from kernel during ipset lookup, (want %zu, got %zu)\n",
			sizeof(struct ip_set_req_get_set), (size_t)size);
		return -1;
	}

	return res;
}

static int
get_set_byid(char *setname, unsigned int idx)
{
	struct ip_set_req_get_set req;
	int res;

	req.op = IP_SET_OP_GET_BYINDEX;
	req.set.index = idx;
	res = do_getsockopt(&req);
	if (res != 0)
		return -1;
	if (req.set.name[0] == '\0') {
		fprintf(stderr,
			"Set with index %i in kernel doesn't exist.\n", idx);
		return -1;
	}

	strncpy(setname, req.set.name, IPSET_MAXNAMELEN);
	return 0;
}

static int
get_set_byname(const char *setname, struct xt_set_info *info)
{
	struct ip_set_req_get_set req;
	int res;

	req.op = IP_SET_OP_GET_BYNAME;
	strlcpy(req.set.name, setname, IPSET_MAXNAMELEN);
	res = do_getsockopt(&req);
	if (res != 0)
		return -1;
	if (req.set.index == IPSET_INVALID_ID)
		return -1;
	info->index = req.set.index;
	return 0;
}

static int
parse_dirs(const char *opt_arg, struct xt_set_info *info)
{
	char *saved = strdup(opt_arg);
	char *ptr, *tmp = saved;

	if (!tmp) {
		perror("strdup");
		return -1;
	}

	while (info->dim < IPSET_DIM_MAX && tmp != NULL) {
		info->dim++;
		ptr = strsep(&tmp, ",");
		if (strncmp(ptr, "src", 3) == 0)
			info->flags |= (1 << info->dim);
		else if (strncmp(ptr, "dst", 3) != 0) {
			fputs("You must specify (the comma separated list of) 'src' or 'dst'\n", stderr);
			free(saved);
			return -1;
		}
	}

	if (tmp)
		fprintf(stderr, "Can't be more src/dst options than %u", IPSET_DIM_MAX);
	free(saved);
	return tmp ? -1 : 0;
}

static void ipset_print_usage(FILE *fd)
{
	fprintf(fd,
	    "Usage: ipset(SETNAME FLAGS)\n" \
	    "where: SETNAME:= string\n" \
	    "       FLAGS  := { FLAG[,FLAGS] }\n" \
	    "       FLAG   := { src | dst }\n" \
	    "\n" \
	    "Example: 'ipset(bulk src,dst)'\n");
}

static int ipset_parse_eopt(struct nlmsghdr *n, struct tcf_ematch_hdr *hdr,
			    struct bstr *args)
{
	struct xt_set_info set_info = {};
	int ret;

#define PARSE_ERR(CARG, FMT, ARGS...) \
	em_parse_error(EINVAL, args, CARG, &ipset_ematch_util, FMT, ##ARGS)

	if (args == NULL)
		return PARSE_ERR(args, "ipset: missing set name");

	if (args->len >= IPSET_MAXNAMELEN)
		return PARSE_ERR(args, "ipset: set name too long (max %u)", IPSET_MAXNAMELEN - 1);
	ret = get_set_byname(args->data, &set_info);
	if (ret < 0)
		return PARSE_ERR(args, "ipset: unknown set name '%s'", args->data);

	if (args->next == NULL)
		return PARSE_ERR(args, "ipset: missing set flags");

	args = bstr_next(args);
	if (parse_dirs(args->data, &set_info))
		return PARSE_ERR(args, "ipset: error parsing set flags");

	if (args->next) {
		args = bstr_next(args);
		return PARSE_ERR(args, "ipset: unknown parameter");
	}

	addraw_l(n, MAX_MSG, hdr, sizeof(*hdr));
	addraw_l(n, MAX_MSG, &set_info, sizeof(set_info));

#undef PARSE_ERR
	return 0;
}

static int ipset_print_eopt(FILE *fd, struct tcf_ematch_hdr *hdr, void *data,
			    int data_len)
{
	int i;
	char setname[IPSET_MAXNAMELEN];
	const struct xt_set_info *set_info = data;

	if (data_len != sizeof(*set_info)) {
		fprintf(stderr, "xt_set_info struct size mismatch\n");
		return -1;
	}

	if (get_set_byid(setname, set_info->index))
		return -1;
	fputs(setname, fd);
	for (i = 1; i <= set_info->dim; i++) {
		fprintf(fd, "%s%s", i == 1 ? " " : ",", set_info->flags & (1 << i) ? "src" : "dst");
	}

	return 0;
}

struct ematch_util ipset_ematch_util = {
	.kind = "ipset",
	.kind_num = TCF_EM_IPSET,
	.parse_eopt = ipset_parse_eopt,
	.print_eopt = ipset_print_eopt,
	.print_usage = ipset_print_usage
};
Commit	Line	Data
8194411a FW	1	/*
	2	* em_ipset.c IPset Ematch
	3	*
	4	* (C) 2012 Florian Westphal <fw@strlen.de>
	5	*
	6	* Parts taken from iptables libxt_set.h:
	7	* Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
	8	* Patrick Schaaf <bof@bof.de>
	9	* Martin Josefsson <gandalf@wlug.westbo.se>
	10	* Copyright (C) 2003-2010 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
	11	*
	12	* This program is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU General Public License version 2 as
	14	* published by the Free Software Foundation.
	15	*/
	16
	17	#include <stdbool.h>
	18	#include <stdio.h>
	19	#include <errno.h>
	20	#include <netdb.h>
	21	#include <unistd.h>
	22	#include <string.h>
	23	#include <stdlib.h>
	24	#include <getopt.h>
	25
	26	#include <xtables.h>
	27	#include <linux/netfilter/ipset/ip_set.h>
	28
	29	#ifndef IPSET_INVALID_ID
	30	typedef __u16 ip_set_id_t;
	31
	32	enum ip_set_dim {
	33	IPSET_DIM_ZERO = 0,
	34	IPSET_DIM_ONE,
	35	IPSET_DIM_TWO,
	36	IPSET_DIM_THREE,
	37	IPSET_DIM_MAX = 6,
	38	};
	39	#endif /* IPSET_INVALID_ID */
	40
	41	#include <linux/netfilter/xt_set.h>
	42	#include "m_ematch.h"
	43
	44	#ifndef IPSET_INVALID_ID
	45	#define IPSET_INVALID_ID 65535
	46	#define SO_IP_SET 83
	47
	48	union ip_set_name_index {
	49	char name[IPSET_MAXNAMELEN];
	50	__u16 index;
	51	};
	52
	53	#define IP_SET_OP_GET_BYNAME 0x00000006 /* Get set index by name */
	54	struct ip_set_req_get_set {
32a121cb SH	55	unsigned int op;
32a121cb SH	56	unsigned int version;
8194411a FW	57	union ip_set_name_index set;
	58	};
	59
	60	#define IP_SET_OP_GET_BYINDEX 0x00000007 /* Get set name by index */
	61	/* Uses ip_set_req_get_set */
	62
	63	#define IP_SET_OP_VERSION 0x00000100 /* Ask kernel version */
	64	struct ip_set_req_version {
32a121cb SH	65	unsigned int op;
32a121cb SH	66	unsigned int version;
8194411a FW	67	};
	68	#endif /* IPSET_INVALID_ID */
	69
	70	extern struct ematch_util ipset_ematch_util;
	71
32a121cb	72	static int get_version(unsigned int *version)
8194411a FW	73	{
	74	int res, sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
	75	struct ip_set_req_version req_version;
	76	socklen_t size = sizeof(req_version);
	77
	78	if (sockfd < 0) {
	79	fputs("Can't open socket to ipset.\n", stderr);
	80	return -1;
	81	}
	82
	83	req_version.op = IP_SET_OP_VERSION;
	84	res = getsockopt(sockfd, SOL_IP, SO_IP_SET, &req_version, &size);
	85	if (res != 0) {
	86	perror("xt_set getsockopt");
3e587d9f	87	close(sockfd);
8194411a FW	88	return -1;
	89	}
	90
	91	*version = req_version.version;
	92	return sockfd;
	93	}
	94
	95	static int do_getsockopt(struct ip_set_req_get_set *req)
	96	{
	97	int sockfd, res;
	98	socklen_t size = sizeof(struct ip_set_req_get_set);
32a121cb	99
8194411a FW	100	sockfd = get_version(&req->version);
	101	if (sockfd < 0)
	102	return -1;
	103	res = getsockopt(sockfd, SOL_IP, SO_IP_SET, req, &size);
	104	if (res != 0)
	105	perror("Problem when communicating with ipset");
	106	close(sockfd);
	107	if (res != 0)
	108	return -1;
	109
	110	if (size != sizeof(struct ip_set_req_get_set)) {
	111	fprintf(stderr,
32a121cb	112	"Incorrect return size from kernel during ipset lookup, (want %zu, got %zu)\n",
8194411a FW	113	sizeof(struct ip_set_req_get_set), (size_t)size);
	114	return -1;
	115	}
	116
	117	return res;
	118	}
	119
	120	static int
	121	get_set_byid(char *setname, unsigned int idx)
	122	{
	123	struct ip_set_req_get_set req;
	124	int res;
	125
	126	req.op = IP_SET_OP_GET_BYINDEX;
	127	req.set.index = idx;
	128	res = do_getsockopt(&req);
	129	if (res != 0)
	130	return -1;
	131	if (req.set.name[0] == '\0') {
	132	fprintf(stderr,
	133	"Set with index %i in kernel doesn't exist.\n", idx);
	134	return -1;
	135	}
	136
	137	strncpy(setname, req.set.name, IPSET_MAXNAMELEN);
	138	return 0;
	139	}
	140
	141	static int
	142	get_set_byname(const char setname, struct xt_set_info info)
	143	{
	144	struct ip_set_req_get_set req;
	145	int res;
	146
	147	req.op = IP_SET_OP_GET_BYNAME;
18f156bf	148	strlcpy(req.set.name, setname, IPSET_MAXNAMELEN);
8194411a FW	149	res = do_getsockopt(&req);
	150	if (res != 0)
	151	return -1;
	152	if (req.set.index == IPSET_INVALID_ID)
	153	return -1;
	154	info->index = req.set.index;
	155	return 0;
	156	}
	157
	158	static int
	159	parse_dirs(const char opt_arg, struct xt_set_info info)
	160	{
32a121cb SH	161	char *saved = strdup(opt_arg);
32a121cb SH	162	char ptr, tmp = saved;
8194411a FW	163
	164	if (!tmp) {
	165	perror("strdup");
	166	return -1;
	167	}
	168
32a121cb SH	169	while (info->dim < IPSET_DIM_MAX && tmp != NULL) {
	170	info->dim++;
	171	ptr = strsep(&tmp, ",");
	172	if (strncmp(ptr, "src", 3) == 0)
	173	info->flags \|= (1 << info->dim);
	174	else if (strncmp(ptr, "dst", 3) != 0) {
	175	fputs("You must specify (the comma separated list of) 'src' or 'dst'\n", stderr);
8194411a FW	176	free(saved);
	177	return -1;
	178	}
32a121cb	179	}
8194411a	180
32a121cb SH	181	if (tmp)
	182	fprintf(stderr, "Can't be more src/dst options than %u", IPSET_DIM_MAX);
	183	free(saved);
8194411a FW	184	return tmp ? -1 : 0;
	185	}
	186
	187	static void ipset_print_usage(FILE *fd)
	188	{
	189	fprintf(fd,
	190	"Usage: ipset(SETNAME FLAGS)\n" \
	191	"where: SETNAME:= string\n" \
	192	" FLAGS := { FLAG[,FLAGS] }\n" \
	193	" FLAG := { src \| dst }\n" \
	194	"\n" \
	195	"Example: 'ipset(bulk src,dst)'\n");
	196	}
	197
	198	static int ipset_parse_eopt(struct nlmsghdr n, struct tcf_ematch_hdr hdr,
	199	struct bstr *args)
	200	{
d17b136f	201	struct xt_set_info set_info = {};
8194411a FW	202	int ret;
8194411a FW	203
8194411a	204	#define PARSE_ERR(CARG, FMT, ARGS...) \
32a121cb	205	em_parse_error(EINVAL, args, CARG, &ipset_ematch_util, FMT, ##ARGS)
8194411a FW	206
	207	if (args == NULL)
	208	return PARSE_ERR(args, "ipset: missing set name");
	209
	210	if (args->len >= IPSET_MAXNAMELEN)
	211	return PARSE_ERR(args, "ipset: set name too long (max %u)", IPSET_MAXNAMELEN - 1);
	212	ret = get_set_byname(args->data, &set_info);
	213	if (ret < 0)
	214	return PARSE_ERR(args, "ipset: unknown set name '%s'", args->data);
	215
	216	if (args->next == NULL)
	217	return PARSE_ERR(args, "ipset: missing set flags");
	218
	219	args = bstr_next(args);
	220	if (parse_dirs(args->data, &set_info))
	221	return PARSE_ERR(args, "ipset: error parsing set flags");
	222
	223	if (args->next) {
	224	args = bstr_next(args);
	225	return PARSE_ERR(args, "ipset: unknown parameter");
	226	}
	227
	228	addraw_l(n, MAX_MSG, hdr, sizeof(*hdr));
	229	addraw_l(n, MAX_MSG, &set_info, sizeof(set_info));
	230
	231	#undef PARSE_ERR
	232	return 0;
	233	}
	234
	235	static int ipset_print_eopt(FILE fd, struct tcf_ematch_hdr hdr, void *data,
	236	int data_len)
	237	{
	238	int i;
32a121cb	239	char setname[IPSET_MAXNAMELEN];
8194411a FW	240	const struct xt_set_info *set_info = data;
	241
	242	if (data_len != sizeof(*set_info)) {
	243	fprintf(stderr, "xt_set_info struct size mismatch\n");
	244	return -1;
	245	}
	246
32a121cb	247	if (get_set_byid(setname, set_info->index))
8194411a FW	248	return -1;
	249	fputs(setname, fd);
	250	for (i = 1; i <= set_info->dim; i++) {
	251	fprintf(fd, "%s%s", i == 1 ? " " : ",", set_info->flags & (1 << i) ? "src" : "dst");
	252	}
	253
	254	return 0;
	255	}
	256
	257	struct ematch_util ipset_ematch_util = {
	258	.kind = "ipset",
	259	.kind_num = TCF_EM_IPSET,
	260	.parse_eopt = ipset_parse_eopt,
	261	.print_eopt = ipset_print_eopt,
	262	.print_usage = ipset_print_usage
	263	};