xref: /freebsd/contrib/bsnmp/snmp_mibII/mibII_ipaddr.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*
2  * Copyright (c) 2001-2002
3  *	Fraunhofer Institute for Open Communication Systems (FhG Fokus).
4  *	All rights reserved.
5  *
6  * Author: Harti Brandt <harti@freebsd.org>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $Begemot: bsnmp/snmp_mibII/mibII_ipaddr.c,v 1.10 2005/10/04 11:21:35 brandt_h Exp $
30  *
31  * IP address table. This table is writeable!
32  *
33  * Writing to this table will add a new IP address to the interface.
34  * An address can be deleted with writing the interface index 0.
35  */
36 #include "mibII.h"
37 #include "mibII_oid.h"
38 
39 static const struct asn_oid
40 	oid_ipAddrTable = OIDX_ipAddrTable;
41 
42 /*
43  * Be careful not to hold any pointers during the SET processing - the
44  * interface and address lists can be relocated at any time.
45  */
46 struct update {
47 	struct snmp_dependency dep;
48 
49 	uint32_t	set;
50 	struct in_addr	addr;
51 	struct in_addr	mask;
52 	int		bcast;
53 	u_int		ifindex;
54 
55 	uint32_t	rb;
56 	struct in_addr	rb_mask;
57 	struct in_addr	rb_bcast;
58 };
59 #define UPD_IFINDEX	0x0001
60 #define UPD_MASK	0x0002
61 #define UPD_BCAST	0x0004
62 #define RB_CREATE	0x0001
63 #define RB_DESTROY	0x0002
64 #define RB_MODIFY	0x0004
65 
66 /*
67  * Create a new interface address
68  */
69 static int
70 create(struct update *upd)
71 {
72 	struct in_addr bcast;
73 	struct mibifa *ifa;
74 
75 	if (!(upd->set & UPD_MASK)) {
76 		if (IN_CLASSA(ntohl(upd->addr.s_addr)))
77 			upd->mask.s_addr = htonl(IN_CLASSA_NET);
78 		else if (IN_CLASSB(ntohl(upd->addr.s_addr)))
79 			upd->mask.s_addr = htonl(IN_CLASSB_NET);
80 		else if (IN_CLASSC(ntohl(upd->addr.s_addr)))
81 			upd->mask.s_addr = htonl(IN_CLASSC_NET);
82 		else
83 			upd->mask.s_addr = 0xffffffff;
84 	}
85 
86 	bcast.s_addr = upd->addr.s_addr & upd->mask.s_addr;
87 	if (!(upd->set & UPD_BCAST) || upd->bcast) {
88 		uint32_t tmp = ~ntohl(upd->mask.s_addr);
89 		bcast.s_addr |= htonl(0xffffffff & ~tmp);
90 	}
91 
92 	if ((ifa = mib_create_ifa(upd->ifindex, upd->addr, upd->mask, bcast))
93 	    == NULL)
94 		return (SNMP_ERR_GENERR);
95 
96 	upd->rb |= RB_CREATE;
97 	return (SNMP_ERR_NOERROR);
98 }
99 
100 /*
101  * Modify the netmask or broadcast address. The ifindex cannot be
102  * changed (obviously).
103  */
104 static int
105 modify(struct update *upd, struct mibifa *ifa)
106 {
107 	struct mibif *ifp;
108 
109 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL)
110 		return (SNMP_ERR_WRONG_VALUE);
111 	if ((upd->set & UPD_IFINDEX) && upd->ifindex != ifa->ifindex)
112 		return (SNMP_ERR_INCONS_VALUE);
113 
114 	upd->rb_mask = ifa->inmask;
115 	upd->rb_bcast = ifa->inbcast;
116 	if (((upd->set & UPD_MASK) && upd->mask.s_addr != ifa->inmask.s_addr) ||
117 	    (upd->set & UPD_BCAST)) {
118 		if (upd->set & UPD_MASK)
119 			ifa->inmask = upd->mask;
120 		if (upd->set & UPD_BCAST) {
121 			ifa->inbcast.s_addr = ifa->inaddr.s_addr
122 			    & ifa->inmask.s_addr;
123 			if (upd->bcast)
124 				ifa->inbcast.s_addr |= 0xffffffff
125 				    & ~ifa->inmask.s_addr;
126 		}
127 		if (mib_modify_ifa(ifa)) {
128 			syslog(LOG_ERR, "set netmask/bcast: %m");
129 			ifa->inmask = upd->rb_mask;
130 			ifa->inbcast = upd->rb_bcast;
131 			mib_unmodify_ifa(ifa);
132 			return (SNMP_ERR_GENERR);
133 		}
134 		upd->rb |= RB_MODIFY;
135 	}
136 	return (SNMP_ERR_NOERROR);
137 }
138 
139 /*
140  * Destroy the given row in the table. We remove the address from the
141  * system, but keep the structure around for the COMMIT. It's deleted
142  * only in the FINISH operation.
143  */
144 static int
145 destroy(struct snmp_context *ctx __unused, struct update *upd,
146     struct mibifa *ifa)
147 {
148 	if (mib_destroy_ifa(ifa))
149 		return (SNMP_ERR_GENERR);
150 	upd->rb |= RB_DESTROY;
151 	return (SNMP_ERR_NOERROR);
152 }
153 
154 /*
155  * This function is called to commit/rollback a SET on an IpAddrEntry
156  */
157 static int
158 update_func(struct snmp_context *ctx, struct snmp_dependency *dep,
159     enum snmp_depop op)
160 {
161 	struct update *upd = (struct update *)dep;
162 	struct mibifa *ifa;
163 
164 	switch (op) {
165 
166 	  case SNMP_DEPOP_COMMIT:
167 		if ((ifa = mib_find_ifa(upd->addr)) == NULL) {
168 			/* non existing entry - must have ifindex */
169 			if (!(upd->set & UPD_IFINDEX))
170 				return (SNMP_ERR_INCONS_NAME);
171 			return (create(upd));
172 		}
173 		/* existing entry */
174 		if ((upd->set & UPD_IFINDEX) && upd->ifindex == 0) {
175 			/* delete */
176 			return (destroy(ctx, upd, ifa));
177 		}
178 		/* modify entry */
179 		return (modify(upd, ifa));
180 
181 	  case SNMP_DEPOP_ROLLBACK:
182 		if ((ifa = mib_find_ifa(upd->addr)) == NULL) {
183 			/* ups */
184 			mib_iflist_bad = 1;
185 			return (SNMP_ERR_NOERROR);
186 		}
187 		if (upd->rb & RB_CREATE) {
188 			mib_uncreate_ifa(ifa);
189 			return (SNMP_ERR_NOERROR);
190 		}
191 		if (upd->rb & RB_DESTROY) {
192 			mib_undestroy_ifa(ifa);
193 			return (SNMP_ERR_NOERROR);
194 		}
195 		if (upd->rb & RB_MODIFY) {
196 			ifa->inmask = upd->rb_mask;
197 			ifa->inbcast = upd->rb_bcast;
198 			mib_unmodify_ifa(ifa);
199 			return (SNMP_ERR_NOERROR);
200 		}
201 		return (SNMP_ERR_NOERROR);
202 
203 	  case SNMP_DEPOP_FINISH:
204 		if ((upd->rb & RB_DESTROY) &&
205 		    (ifa = mib_find_ifa(upd->addr)) != NULL &&
206 		    (ifa->flags & MIBIFA_DESTROYED)) {
207 			TAILQ_REMOVE(&mibifa_list, ifa, link);
208 			free(ifa);
209 		}
210 		return (SNMP_ERR_NOERROR);
211 	}
212 	abort();
213 }
214 
215 /**********************************************************************/
216 /*
217  * ACTION
218  */
219 int
220 op_ipaddr(struct snmp_context *ctx, struct snmp_value *value,
221     u_int sub, u_int iidx, enum snmp_op op)
222 {
223 	asn_subid_t which;
224 	struct mibifa *ifa;
225 	struct update *upd;
226 	struct asn_oid idx;
227 	u_char ipaddr[4];
228 
229 	which = value->var.subs[sub - 1];
230 
231 	ifa = NULL;
232 
233 	switch (op) {
234 
235 	  case SNMP_OP_GETNEXT:
236 		if ((ifa = NEXT_OBJECT_OID(&mibifa_list, &value->var, sub)) == NULL)
237 			return (SNMP_ERR_NOSUCHNAME);
238 		index_append(&value->var, sub, &ifa->index);
239 		break;
240 
241 	  case SNMP_OP_GET:
242 		if ((ifa = FIND_OBJECT_OID(&mibifa_list, &value->var, sub)) == NULL)
243 			return (SNMP_ERR_NOSUCHNAME);
244 		break;
245 
246 	  case SNMP_OP_SET:
247 		if (index_decode(&value->var, sub, iidx, ipaddr))
248 			return (SNMP_ERR_NO_CREATION);
249 		ifa = FIND_OBJECT_OID(&mibifa_list, &value->var, sub);
250 		idx.len = 4;
251 		idx.subs[0] = ipaddr[0];
252 		idx.subs[1] = ipaddr[1];
253 		idx.subs[2] = ipaddr[2];
254 		idx.subs[3] = ipaddr[3];
255 
256 		if ((upd = (struct update *)snmp_dep_lookup(ctx,
257 		    &oid_ipAddrTable, &idx, sizeof(*upd), update_func)) == NULL)
258 			return (SNMP_ERR_RES_UNAVAIL);
259 
260 		upd->addr.s_addr = htonl((ipaddr[0] << 24) | (ipaddr[1] << 16) |
261 		    (ipaddr[2] << 8) | (ipaddr[3] << 0));
262 
263 		switch (which) {
264 
265 		  case LEAF_ipAdEntIfIndex:
266 			if (upd->set & UPD_IFINDEX)
267 				return (SNMP_ERR_INCONS_VALUE);
268 			if (value->v.integer < 0 ||
269 			    value->v.integer > 0x07fffffff)
270 				return (SNMP_ERR_WRONG_VALUE);
271 			if (ifa != NULL) {
272 				if (ifa->ifindex != (u_int)value->v.integer &&
273 				    value->v.integer != 0)
274 					return (SNMP_ERR_INCONS_VALUE);
275 			}
276 			upd->set |= UPD_IFINDEX;
277 			upd->ifindex = (u_int)value->v.integer;
278 			break;
279 
280 		  case LEAF_ipAdEntNetMask:
281 			if (upd->set & UPD_MASK)
282 				return (SNMP_ERR_INCONS_VALUE);
283 			upd->mask.s_addr = htonl((value->v.ipaddress[0] << 24)
284 			    | (value->v.ipaddress[1] << 16)
285 			    | (value->v.ipaddress[2] << 8)
286 			    | (value->v.ipaddress[3] << 0));
287 			upd->set |= UPD_MASK;
288 			break;
289 
290 		  case LEAF_ipAdEntBcastAddr:
291 			if (upd->set & UPD_BCAST)
292 				return (SNMP_ERR_INCONS_VALUE);
293 			if (value->v.integer != 0 && value->v.integer != 1)
294 				return (SNMP_ERR_WRONG_VALUE);
295 			upd->bcast = value->v.integer;
296 			upd->set |= UPD_BCAST;
297 			break;
298 
299 		}
300 		return (SNMP_ERR_NOERROR);
301 
302 	  case SNMP_OP_ROLLBACK:
303 	  case SNMP_OP_COMMIT:
304 		return (SNMP_ERR_NOERROR);
305 	}
306 
307 	switch (which) {
308 
309 	  case LEAF_ipAdEntAddr:
310 		value->v.ipaddress[0] = ifa->index.subs[0];
311 		value->v.ipaddress[1] = ifa->index.subs[1];
312 		value->v.ipaddress[2] = ifa->index.subs[2];
313 		value->v.ipaddress[3] = ifa->index.subs[3];
314 		break;
315 
316 	  case LEAF_ipAdEntIfIndex:
317 		if (ifa->flags & MIBIFA_DESTROYED)
318 			value->v.integer = 0;
319 		else
320 			value->v.integer = ifa->ifindex;
321 		break;
322 
323 	  case LEAF_ipAdEntNetMask:
324 		value->v.ipaddress[0] = (ntohl(ifa->inmask.s_addr) >> 24) & 0xff;
325 		value->v.ipaddress[1] = (ntohl(ifa->inmask.s_addr) >> 16) & 0xff;
326 		value->v.ipaddress[2] = (ntohl(ifa->inmask.s_addr) >>  8) & 0xff;
327 		value->v.ipaddress[3] = (ntohl(ifa->inmask.s_addr) >>  0) & 0xff;
328 		break;
329 
330 	  case LEAF_ipAdEntBcastAddr:
331 		value->v.integer = ntohl(ifa->inbcast.s_addr) & 1;
332 		break;
333 
334 
335 	  case LEAF_ipAdEntReasmMaxSize:
336 		value->v.integer = 65535;
337 		break;
338 	}
339 	return (SNMP_ERR_NOERROR);
340 }
341