xref: /freebsd/sys/netlink/route/iface_drivers.c (revision ce9f95bd835ec7d3ac6def5a910282509b1413f0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 #include "opt_inet.h"
31 #include "opt_inet6.h"
32 #include <sys/types.h>
33 #include <sys/malloc.h>
34 #include <sys/socket.h>
35 #include <sys/sockio.h>
36 #include <sys/syslog.h>
37 #include <sys/socketvar.h>
38 
39 #include <net/ethernet.h>
40 #include <net/if.h>
41 #include <net/if_dl.h>
42 #include <net/if_media.h>
43 #include <net/if_var.h>
44 #include <net/if_clone.h>
45 #include <net/if_vlan_var.h>
46 #include <net/route.h>
47 #include <net/route/nhop.h>
48 #include <net/route/route_ctl.h>
49 #include <netlink/netlink.h>
50 #include <netlink/netlink_ctl.h>
51 #include <netlink/netlink_route.h>
52 #include <netlink/route/route_var.h>
53 
54 #include <netinet6/scope6_var.h> /* scope deembedding */
55 
56 #define	DEBUG_MOD_NAME	nl_iface_drivers
57 #define	DEBUG_MAX_LEVEL	LOG_DEBUG3
58 #include <netlink/netlink_debug.h>
59 _DECLARE_DEBUG(LOG_DEBUG);
60 
61 /*
62  * Generic modification interface handler.
63  * Responsible for changing network stack interface attributes
64  * such as state, mtu or description.
65  */
66 static int
67 modify_generic(struct ifnet *ifp, struct nl_parsed_link *lattrs,
68     const struct nlattr_bmask *bm, struct nlpcb *nlp, struct nl_pstate *npt)
69 {
70 	int error;
71 
72 	if (lattrs->ifla_ifalias != NULL) {
73 		if (nlp_has_priv(nlp, PRIV_NET_SETIFDESCR)) {
74 			int len = strlen(lattrs->ifla_ifalias) + 1;
75 			char *buf = if_allocdescr(len, M_WAITOK);
76 
77 			memcpy(buf, lattrs->ifla_ifalias, len);
78 			if_setdescr(ifp, buf);
79 			getmicrotime(&ifp->if_lastchange);
80 		} else {
81 			nlmsg_report_err_msg(npt, "Not enough privileges to set descr");
82 			return (EPERM);
83 		}
84 	}
85 
86 	if ((lattrs->ifi_change & IFF_UP) && (lattrs->ifi_flags & IFF_UP) == 0) {
87 		/* Request to down the interface */
88 		if_down(ifp);
89 	}
90 
91 	if (lattrs->ifla_mtu > 0) {
92 		if (nlp_has_priv(nlp, PRIV_NET_SETIFMTU)) {
93 			struct ifreq ifr = { .ifr_mtu = lattrs->ifla_mtu };
94 			error = ifhwioctl(SIOCSIFMTU, ifp, (char *)&ifr, curthread);
95 		} else {
96 			nlmsg_report_err_msg(npt, "Not enough privileges to set mtu");
97 			return (EPERM);
98 		}
99 	}
100 
101 	if (lattrs->ifi_change & IFF_PROMISC) {
102 		error = ifpromisc(ifp, lattrs->ifi_flags & IFF_PROMISC);
103 		if (error != 0) {
104 			nlmsg_report_err_msg(npt, "unable to set promisc");
105 			return (error);
106 		}
107 	}
108 
109 	return (0);
110 }
111 
112 /*
113  * Saves the resulting ifindex and ifname to report them
114  *  to userland along with the operation result.
115  * NLA format:
116  * NLMSGERR_ATTR_COOKIE(nested)
117  *  IFLA_NEW_IFINDEX(u32)
118  *  IFLA_IFNAME(string)
119  */
120 static void
121 store_cookie(struct nl_pstate *npt, struct ifnet *ifp)
122 {
123 	int ifname_len = strlen(if_name(ifp));
124 	uint32_t ifindex = (uint32_t)ifp->if_index;
125 
126 	int nla_len = sizeof(struct nlattr) * 3 +
127 		sizeof(ifindex) + NL_ITEM_ALIGN(ifname_len + 1);
128 	struct nlattr *nla_cookie = npt_alloc(npt, nla_len);
129 
130 	/* Nested TLV */
131 	nla_cookie->nla_len = nla_len;
132 	nla_cookie->nla_type = NLMSGERR_ATTR_COOKIE;
133 
134 	struct nlattr *nla = nla_cookie + 1;
135 	nla->nla_len = sizeof(struct nlattr) + sizeof(ifindex);
136 	nla->nla_type = IFLA_NEW_IFINDEX;
137 	memcpy(NLA_DATA(nla), &ifindex, sizeof(ifindex));
138 
139 	nla = NLA_NEXT(nla);
140 	nla->nla_len = sizeof(struct nlattr) + ifname_len + 1;
141 	nla->nla_type = IFLA_IFNAME;
142 	strlcpy(NLA_DATA(nla), if_name(ifp), ifname_len + 1);
143 
144 	nlmsg_report_cookie(npt, nla_cookie);
145 }
146 
147 static int
148 create_generic_ifd(struct nl_parsed_link *lattrs, const struct nlattr_bmask *bm,
149     struct ifc_data *ifd, struct nlpcb *nlp, struct nl_pstate *npt)
150 {
151 	int error = 0;
152 
153 	struct ifnet *ifp = NULL;
154 	error = ifc_create_ifp(lattrs->ifla_ifname, ifd, &ifp);
155 
156 	NLP_LOG(LOG_DEBUG2, nlp, "clone for %s returned %d", lattrs->ifla_ifname, error);
157 
158 	if (error == 0) {
159 		struct epoch_tracker et;
160 
161 		NET_EPOCH_ENTER(et);
162 		bool success = if_try_ref(ifp);
163 		NET_EPOCH_EXIT(et);
164 		if (!success)
165 			return (EINVAL);
166 		error = modify_generic(ifp, lattrs, bm, nlp, npt);
167 		if (error == 0)
168 			store_cookie(npt, ifp);
169 		if_rele(ifp);
170 	}
171 
172 	return (error);
173 }
174 /*
175  * Generic creation interface handler.
176  * Responsible for creating interfaces w/o parameters and setting
177  * misc attributes such as state, mtu or description.
178  */
179 static int
180 create_generic(struct nl_parsed_link *lattrs, const struct nlattr_bmask *bm,
181     struct nlpcb *nlp, struct nl_pstate *npt)
182 {
183 	struct ifc_data ifd = {};
184 
185 	return (create_generic_ifd(lattrs, bm, &ifd, nlp, npt));
186 }
187 
188 struct nl_cloner generic_cloner = {
189 	.name = "_default_",
190 	.create_f = create_generic,
191 	.modify_f = modify_generic,
192 };
193 
194 /*
195  *
196  * {len=76, type=RTM_NEWLINK, flags=NLM_F_REQUEST|NLM_F_ACK|NLM_F_EXCL|NLM_F_CREATE, seq=1662892737, pid=0},
197  *  {ifi_family=AF_UNSPEC, ifi_type=ARPHRD_NETROM, ifi_index=0, ifi_flags=0, ifi_change=0},
198  *   [
199  *    {{nla_len=8, nla_type=IFLA_LINK}, 2},
200  *    {{nla_len=12, nla_type=IFLA_IFNAME}, "xvlan22"},
201  *    {{nla_len=24, nla_type=IFLA_LINKINFO},
202  *     [
203  *      {{nla_len=8, nla_type=IFLA_INFO_KIND}, "vlan"...},
204  *      {{nla_len=12, nla_type=IFLA_INFO_DATA}, "\x06\x00\x01\x00\x16\x00\x00\x00"}]}]}, iov_len=76}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 76
205  */
206 
207 struct nl_parsed_vlan {
208 	uint16_t vlan_id;
209 	uint16_t vlan_proto;
210 	struct ifla_vlan_flags vlan_flags;
211 };
212 
213 #define	_OUT(_field)	offsetof(struct nl_parsed_vlan, _field)
214 static const struct nlattr_parser nla_p_vlan[] = {
215 	{ .type = IFLA_VLAN_ID, .off = _OUT(vlan_id), .cb = nlattr_get_uint16 },
216 	{ .type = IFLA_VLAN_FLAGS, .off = _OUT(vlan_flags), .cb = nlattr_get_nla },
217 	{ .type = IFLA_VLAN_PROTOCOL, .off = _OUT(vlan_proto), .cb = nlattr_get_uint16 },
218 };
219 #undef _OUT
220 NL_DECLARE_ATTR_PARSER(vlan_parser, nla_p_vlan);
221 
222 static int
223 create_vlan(struct nl_parsed_link *lattrs, const struct nlattr_bmask *bm,
224     struct nlpcb *nlp, struct nl_pstate *npt)
225 {
226 	struct epoch_tracker et;
227         struct ifnet *ifp;
228 	int error;
229 
230 	/*
231 	 * lattrs.ifla_ifname is the new interface name
232 	 * lattrs.ifi_index contains parent interface index
233 	 * lattrs.ifla_idata contains un-parsed vlan data
234 	 */
235 
236 	struct nl_parsed_vlan attrs = {
237 		.vlan_id = 0xFEFE,
238 		.vlan_proto = ETHERTYPE_VLAN
239 	};
240 	NLP_LOG(LOG_DEBUG3, nlp, "nested: %p len %d", lattrs->ifla_idata, lattrs->ifla_idata->nla_len);
241 
242 	if (lattrs->ifla_idata == NULL) {
243 		NLMSG_REPORT_ERR_MSG(npt, "vlan id is required, guessing not supported");
244 		return (ENOTSUP);
245 	}
246 
247 	error = nl_parse_nested(lattrs->ifla_idata, &vlan_parser, npt, &attrs);
248 	if (error != 0)
249 		return (error);
250 	if (attrs.vlan_id > 4095) {
251 		NLMSG_REPORT_ERR_MSG(npt, "Invalid VID: %d", attrs.vlan_id);
252 		return (EINVAL);
253 	}
254 	if (attrs.vlan_proto != ETHERTYPE_VLAN && attrs.vlan_proto != ETHERTYPE_QINQ) {
255 		NLMSG_REPORT_ERR_MSG(npt, "Unsupported ethertype: 0x%04X", attrs.vlan_proto);
256 		return (ENOTSUP);
257 	}
258 
259 	NET_EPOCH_ENTER(et);
260 	ifp = ifnet_byindex_ref(lattrs->ifi_index);
261 	NET_EPOCH_EXIT(et);
262 	if (ifp == NULL) {
263 		NLP_LOG(LOG_DEBUG, nlp, "unable to find parent interface %u",
264 		    lattrs->ifi_index);
265 		return (ENOENT);
266 	}
267 
268 	struct vlanreq params = {
269 		.vlr_tag = attrs.vlan_id,
270 		.vlr_proto = attrs.vlan_proto,
271 	};
272 	strlcpy(params.vlr_parent, if_name(ifp), sizeof(params.vlr_parent));
273 	struct ifc_data ifd = { .flags = IFC_F_SYSSPACE, .params = &params };
274 
275 	error = create_generic_ifd(lattrs, bm, &ifd, nlp, npt);
276 
277 	if_rele(ifp);
278 	return (error);
279 }
280 
281 static int
282 dump_vlan(struct ifnet *ifp, struct nl_writer *nw)
283 {
284 	return (0);
285 }
286 
287 static struct nl_cloner vlan_cloner = {
288 	.name = "vlan",
289 	.create_f = create_vlan,
290 	.modify_f = modify_generic,
291 	.dump_f = dump_vlan,
292 
293 };
294 
295 static const struct nlhdr_parser *all_parsers[] = { &vlan_parser };
296 
297 void
298 rtnl_iface_drivers_register(void)
299 {
300 	rtnl_iface_add_cloner(&vlan_cloner);
301 	NL_VERIFY_PARSERS(all_parsers);
302 }
303 
304 
305