1 | /* |
2 | * Copyright (c) 2011-2017 Apple Inc. All rights reserved. |
3 | * |
4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ |
5 | * |
6 | * This file contains Original Code and/or Modifications of Original Code |
7 | * as defined in and that are subject to the Apple Public Source License |
8 | * Version 2.0 (the 'License'). You may not use this file except in |
9 | * compliance with the License. The rights granted to you under the License |
10 | * may not be used to create, or enable the creation or redistribution of, |
11 | * unlawful or unlicensed copies of an Apple operating system, or to |
12 | * circumvent, violate, or enable the circumvention or violation of, any |
13 | * terms of an Apple operating system software license agreement. |
14 | * |
15 | * Please obtain a copy of the License at |
16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. |
17 | * |
18 | * The Original Code and all software distributed under the License are |
19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
23 | * Please see the License for the specific language governing rights and |
24 | * limitations under the License. |
25 | * |
26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
27 | */ |
28 | |
29 | // Include netinet/in.h first. net/netsrc.h depends on netinet/in.h but |
30 | // netinet/in.h doesn't work with -Wpadded, -Wpacked. |
31 | #include <netinet/in.h> |
32 | |
33 | #pragma clang diagnostic push |
34 | #pragma clang diagnostic error "-Wpadded" |
35 | #pragma clang diagnostic error "-Wpacked" |
36 | // This header defines structures shared with user space, so we need to ensure there is |
37 | // no compiler inserted padding in case the user space process isn't using the same |
38 | // architecture as the kernel (example: i386 process with x86_64 kernel). |
39 | #include <net/netsrc.h> |
40 | #pragma clang diagnostic pop |
41 | |
42 | #include <sys/param.h> |
43 | #include <sys/types.h> |
44 | #include <sys/kpi_mbuf.h> |
45 | #include <sys/socket.h> |
46 | #include <sys/kern_control.h> |
47 | #include <sys/mcache.h> |
48 | #include <sys/socketvar.h> |
49 | |
50 | #include <kern/debug.h> |
51 | |
52 | #include <libkern/libkern.h> |
53 | |
54 | #include <net/if.h> |
55 | #include <net/route.h> |
56 | |
57 | #include <netinet/in.h> |
58 | #include <netinet/ip.h> |
59 | #include <netinet/ip_var.h> |
60 | #include <netinet/in_var.h> |
61 | #include <netinet/ip6.h> |
62 | #include <netinet6/ip6_var.h> |
63 | |
64 | #include <net/ntstat.h> |
65 | |
66 | static errno_t |
67 | netsrc_ctlconnect(kern_ctl_ref kctl, struct sockaddr_ctl *sac, void **uinfo) |
68 | { |
69 | #pragma unused(kctl, sac, uinfo) |
70 | |
71 | /* |
72 | * We don't need to do anything here. This callback is only necessary |
73 | * for ctl_register() to succeed. |
74 | */ |
75 | return 0; |
76 | } |
77 | |
78 | static errno_t |
79 | netsrc_reply(kern_ctl_ref kctl, uint32_t unit, unsigned int version, |
80 | struct netsrc_rep *reply) |
81 | { |
82 | switch (version) { |
83 | case NETSRC_CURVERS: |
84 | return ctl_enqueuedata(kctlref: kctl, unit, data: reply, |
85 | len: sizeof(*reply), CTL_DATA_EOR); |
86 | case NETSRC_VERSION1: { |
87 | if ((reply->nrp_flags & NETSRC_FLAG_ROUTEABLE) == 0) { |
88 | return EHOSTUNREACH; |
89 | } |
90 | #define NETSRC_FLAG_V1_MASK (NETSRC_IP6_FLAG_TENTATIVE | \ |
91 | NETSRC_IP6_FLAG_TEMPORARY | \ |
92 | NETSRC_IP6_FLAG_DEPRECATED | \ |
93 | NETSRC_IP6_FLAG_OPTIMISTIC | \ |
94 | NETSRC_IP6_FLAG_SECURED) |
95 | struct netsrc_repv1 v1 = { |
96 | .nrp_src = reply->nrp_src, |
97 | .nrp_flags = (reply->nrp_flags & NETSRC_FLAG_V1_MASK), |
98 | .nrp_label = reply->nrp_label, |
99 | .nrp_precedence = reply->nrp_precedence, |
100 | .nrp_dstlabel = reply->nrp_dstlabel, |
101 | .nrp_dstprecedence = reply->nrp_dstprecedence |
102 | }; |
103 | return ctl_enqueuedata(kctlref: kctl, unit, data: &v1, len: sizeof(v1), CTL_DATA_EOR); |
104 | } |
105 | } |
106 | return EINVAL; |
107 | } |
108 | |
109 | static void |
110 | netsrc_common(struct rtentry *rt, struct netsrc_rep *reply) |
111 | { |
112 | if (!rt) { |
113 | return; |
114 | } |
115 | |
116 | // Gather statistics information |
117 | struct nstat_counts *rt_stats = rt->rt_stats; |
118 | if (rt_stats) { |
119 | reply->nrp_min_rtt = rt_stats->nstat_min_rtt; |
120 | reply->nrp_connection_attempts = rt_stats->nstat_connectattempts; |
121 | reply->nrp_connection_successes = rt_stats->nstat_connectsuccesses; |
122 | } |
123 | |
124 | // If this route didn't have any stats, check its parent |
125 | if (reply->nrp_min_rtt == 0) { |
126 | // Is this lock necessary? |
127 | RT_LOCK(rt); |
128 | if (rt->rt_parent) { |
129 | rt_stats = rt->rt_parent->rt_stats; |
130 | if (rt_stats) { |
131 | reply->nrp_min_rtt = rt_stats->nstat_min_rtt; |
132 | reply->nrp_connection_attempts = rt_stats->nstat_connectattempts; |
133 | reply->nrp_connection_successes = rt_stats->nstat_connectsuccesses; |
134 | } |
135 | } |
136 | RT_UNLOCK(rt); |
137 | } |
138 | reply->nrp_ifindex = rt->rt_ifp ? rt->rt_ifp->if_index : 0; |
139 | |
140 | if (rt->rt_ifp != NULL && (rt->rt_ifp->if_eflags & IFEF_AWDL)) { |
141 | reply->nrp_flags |= NETSRC_FLAG_AWDL; |
142 | } |
143 | if (rt->rt_flags & RTF_LOCAL) { |
144 | reply->nrp_flags |= NETSRC_FLAG_DIRECT; |
145 | } else if (!(rt->rt_flags & RTF_GATEWAY) && |
146 | (rt->rt_ifa && rt->rt_ifa->ifa_ifp && |
147 | !(rt->rt_ifa->ifa_ifp->if_flags & IFF_POINTOPOINT))) { |
148 | reply->nrp_flags |= NETSRC_FLAG_DIRECT; |
149 | } |
150 | } |
151 | |
152 | static struct in6_addrpolicy * |
153 | lookup_policy(struct sockaddr* sa) |
154 | { |
155 | // alignment fun - if sa_family is AF_INET or AF_INET6, this is one of those |
156 | // addresses and it should be aligned, so this should be safe. |
157 | union sockaddr_in_4_6 *addr = (union sockaddr_in_4_6 *)(void*)sa; |
158 | if (addr->sa.sa_family == AF_INET6) { |
159 | return in6_addrsel_lookup_policy(&addr->sin6); |
160 | } else if (sa->sa_family == AF_INET) { |
161 | struct sockaddr_in6 mapped = { |
162 | .sin6_family = AF_INET6, |
163 | .sin6_len = sizeof(mapped), |
164 | .sin6_addr = IN6ADDR_V4MAPPED_INIT, |
165 | }; |
166 | mapped.sin6_addr.s6_addr32[3] = addr->sin.sin_addr.s_addr; |
167 | return in6_addrsel_lookup_policy(&mapped); |
168 | } |
169 | return NULL; |
170 | } |
171 | |
172 | static void |
173 | netsrc_policy_common(struct netsrc_req *request, struct netsrc_rep *reply) |
174 | { |
175 | // Destination policy |
176 | struct in6_addrpolicy *policy = lookup_policy(SA(&request->nrq_dst.sa)); |
177 | if (policy != NULL && policy->label != -1) { |
178 | /* Explicit cast because both policy and netsrc are public APIs |
179 | * and apps might rely on it. |
180 | */ |
181 | reply->nrp_dstlabel = (uint16_t)policy->label; |
182 | reply->nrp_dstprecedence = (uint16_t)policy->preced; |
183 | } |
184 | |
185 | // Source policy |
186 | policy = lookup_policy(SA(&reply->nrp_src.sa)); |
187 | if (policy != NULL && policy->label != -1) { |
188 | /* Explicit cast because both policy and netsrc are public APIs |
189 | * and apps might rely on it. |
190 | */ |
191 | reply->nrp_label = (uint16_t)policy->label; |
192 | reply->nrp_precedence = (uint16_t)policy->preced; |
193 | } |
194 | } |
195 | |
196 | static errno_t |
197 | netsrc_ipv6(kern_ctl_ref kctl, uint32_t unit, struct netsrc_req *request) |
198 | { |
199 | struct route_in6 ro = { |
200 | .ro_dst = request->nrq_sin6, |
201 | }; |
202 | |
203 | int error = 0; |
204 | struct in6_addr storage, *in6 = in6_selectsrc(&request->nrq_sin6, NULL, |
205 | NULL, &ro, NULL, &storage, |
206 | request->nrq_ifscope, &error); |
207 | struct netsrc_rep reply = { |
208 | .nrp_sin6.sin6_family = AF_INET6, |
209 | .nrp_sin6.sin6_len = sizeof(reply.nrp_sin6), |
210 | .nrp_sin6.sin6_addr = in6 ? *in6 : (struct in6_addr){}, |
211 | }; |
212 | netsrc_common(rt: ro.ro_rt, reply: &reply); |
213 | if (ro.ro_srcia == NULL && in6 != NULL) { |
214 | ro.ro_srcia = (struct ifaddr *)ifa_foraddr6_scoped(in6, reply.nrp_ifindex); |
215 | } |
216 | if (ro.ro_srcia) { |
217 | struct in6_ifaddr *ia = (struct in6_ifaddr *)ro.ro_srcia; |
218 | #define IA_TO_NRP_FLAG(flag) \ |
219 | if (ia->ia6_flags & IN6_IFF_##flag) { \ |
220 | reply.nrp_flags |= NETSRC_FLAG_IP6_##flag; \ |
221 | } |
222 | IA_TO_NRP_FLAG(TENTATIVE); |
223 | IA_TO_NRP_FLAG(TEMPORARY); |
224 | IA_TO_NRP_FLAG(DEPRECATED); |
225 | IA_TO_NRP_FLAG(OPTIMISTIC); |
226 | IA_TO_NRP_FLAG(SECURED); |
227 | IA_TO_NRP_FLAG(DYNAMIC); |
228 | IA_TO_NRP_FLAG(AUTOCONF); |
229 | #undef IA_TO_NRP_FLAG |
230 | reply.nrp_flags |= NETSRC_FLAG_ROUTEABLE; |
231 | } |
232 | ROUTE_RELEASE(&ro); |
233 | netsrc_policy_common(request, reply: &reply); |
234 | return netsrc_reply(kctl, unit, version: request->nrq_ver, reply: &reply); |
235 | } |
236 | |
237 | static errno_t |
238 | netsrc_ipv4(kern_ctl_ref kctl, uint32_t unit, struct netsrc_req *request) |
239 | { |
240 | // Unfortunately, IPv4 doesn't have a function like in6_selectsrc |
241 | // Look up the route |
242 | lck_mtx_lock(rnh_lock); |
243 | struct rtentry *rt = rt_lookup(TRUE, SA(&request->nrq_dst.sa), |
244 | NULL, rt_tables[AF_INET], |
245 | request->nrq_ifscope); |
246 | lck_mtx_unlock(rnh_lock); |
247 | |
248 | // Look up the ifa |
249 | struct netsrc_rep reply = {}; |
250 | if (rt) { |
251 | struct in_ifaddr *ia = NULL; |
252 | lck_rw_lock_shared(lck: &in_ifaddr_rwlock); |
253 | TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) { |
254 | IFA_LOCK_SPIN(&ia->ia_ifa); |
255 | if (ia->ia_ifp == rt->rt_ifp) { |
256 | ifa_addref(ifa: &ia->ia_ifa); |
257 | break; |
258 | } |
259 | IFA_UNLOCK(&ia->ia_ifa); |
260 | } |
261 | lck_rw_done(lck: &in_ifaddr_rwlock); |
262 | |
263 | if (ia) { |
264 | reply.nrp_sin = *IA_SIN(ia); |
265 | IFA_UNLOCK(&ia->ia_ifa); |
266 | ifa_remref(ifa: &ia->ia_ifa); |
267 | reply.nrp_flags |= NETSRC_FLAG_ROUTEABLE; |
268 | } |
269 | netsrc_common(rt, reply: &reply); |
270 | rtfree(rt); |
271 | } |
272 | netsrc_policy_common(request, reply: &reply); |
273 | return netsrc_reply(kctl, unit, version: request->nrq_ver, reply: &reply); |
274 | } |
275 | |
276 | static errno_t |
277 | netsrc_ctlsend(kern_ctl_ref kctl, uint32_t unit, void *uinfo, mbuf_t m, |
278 | int flags) |
279 | { |
280 | #pragma unused(uinfo, flags) |
281 | errno_t error; |
282 | struct netsrc_req *nrq, storage; |
283 | |
284 | if (mbuf_pkthdr_len(mbuf: m) < sizeof(*nrq)) { |
285 | error = EINVAL; |
286 | goto out; |
287 | } |
288 | if (mbuf_len(mbuf: m) >= sizeof(*nrq)) { |
289 | nrq = mbuf_data(mbuf: m); |
290 | } else { |
291 | mbuf_copydata(mbuf: m, offset: 0, length: sizeof(storage), out_data: &storage); |
292 | nrq = &storage; |
293 | } |
294 | if (nrq->nrq_ver > NETSRC_CURVERS) { |
295 | error = EINVAL; |
296 | goto out; |
297 | } |
298 | switch (nrq->nrq_sin.sin_family) { |
299 | case AF_INET: |
300 | if (nrq->nrq_sin.sin_len < sizeof(nrq->nrq_sin) || |
301 | nrq->nrq_sin.sin_addr.s_addr == INADDR_ANY) { |
302 | error = EINVAL; |
303 | } else { |
304 | error = netsrc_ipv4(kctl, unit, request: nrq); |
305 | } |
306 | break; |
307 | case AF_INET6: |
308 | if (nrq->nrq_sin6.sin6_len < sizeof(nrq->nrq_sin6) || |
309 | IN6_IS_ADDR_UNSPECIFIED(&nrq->nrq_sin6.sin6_addr)) { |
310 | error = EINVAL; |
311 | } else { |
312 | error = netsrc_ipv6(kctl, unit, request: nrq); |
313 | } |
314 | break; |
315 | default: |
316 | printf("%s: invalid family\n" , __func__); |
317 | error = EINVAL; |
318 | } |
319 | out: |
320 | mbuf_freem(mbuf: m); |
321 | |
322 | return error; |
323 | } |
324 | |
325 | __private_extern__ void |
326 | netsrc_init(void) |
327 | { |
328 | struct kern_ctl_reg netsrc_ctl = { |
329 | .ctl_connect = netsrc_ctlconnect, |
330 | .ctl_send = netsrc_ctlsend, |
331 | }; |
332 | |
333 | strlcpy(dst: netsrc_ctl.ctl_name, NETSRC_CTLNAME, n: sizeof(netsrc_ctl.ctl_name)); |
334 | |
335 | static kern_ctl_ref netsrc_ctlref = NULL; |
336 | errno_t error = ctl_register(userkctl: &netsrc_ctl, kctlref: &netsrc_ctlref); |
337 | if (error != 0) { |
338 | printf("%s: ctl_register failed %d\n" , __func__, error); |
339 | } |
340 | } |
341 | |