xref: /freebsd/contrib/bsnmp/snmp_mibII/mibII_ipaddr.c (revision 8ab2f5ecc596131f6ca790d6ae35540c06ed7985)
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 of this software and documentation and use in source and
9  * binary forms, with or without modification, are permitted provided that
10  * the following conditions are met:
11  *
12  * 1. Redistributions of source code or documentation must retain the above
13  *    copyright notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE AND DOCUMENTATION IS PROVIDED BY FRAUNHOFER FOKUS
22  * AND ITS CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
23  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
24  * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
25  * FRAUNHOFER FOKUS OR ITS CONTRIBUTORS  BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
28  * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
29  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
31  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  *
33  * $Begemot: bsnmp/snmp_mibII/mibII_ipaddr.c,v 1.8 2004/04/13 14:58:46 novo Exp $
34  *
35  * IP address table. This table is writeable!
36  *
37  * Writing to this table will add a new IP address to the interface.
38  * An address can be deleted with writing the interface index 0.
39  */
40 #include "mibII.h"
41 #include "mibII_oid.h"
42 
43 static const struct asn_oid
44 	oid_ipAddrTable = OIDX_ipAddrTable;
45 
46 /*
47  * Be careful not to hold any pointers during the SET processing - the
48  * interface and address lists can be relocated at any time.
49  */
50 struct update {
51 	struct snmp_dependency dep;
52 
53 	u_int32_t	set;
54 	struct in_addr	addr;
55 	struct in_addr	mask;
56 	int		bcast;
57 	u_int		ifindex;
58 
59 	u_int32_t	rb;
60 	struct in_addr	rb_mask;
61 	struct in_addr	rb_bcast;
62 };
63 #define UPD_IFINDEX	0x0001
64 #define UPD_MASK	0x0002
65 #define UPD_BCAST	0x0004
66 #define RB_CREATE	0x0001
67 #define RB_DESTROY	0x0002
68 #define RB_MODIFY	0x0004
69 
70 /*
71  * Create a new interface address
72  */
73 static int
74 create(struct update *upd)
75 {
76 	struct in_addr bcast;
77 	struct mibifa *ifa;
78 
79 	if (!(upd->set & UPD_MASK)) {
80 		if (IN_CLASSA(ntohl(upd->addr.s_addr)))
81 			upd->mask.s_addr = htonl(IN_CLASSA_NET);
82 		else if (IN_CLASSB(ntohl(upd->addr.s_addr)))
83 			upd->mask.s_addr = htonl(IN_CLASSB_NET);
84 		else if (IN_CLASSC(ntohl(upd->addr.s_addr)))
85 			upd->mask.s_addr = htonl(IN_CLASSC_NET);
86 		else
87 			upd->mask.s_addr = 0xffffffff;
88 	}
89 
90 	bcast.s_addr = upd->addr.s_addr & upd->mask.s_addr;
91 	if (!(upd->set & UPD_BCAST) || upd->bcast)
92 		bcast.s_addr |= htonl(0xffffffff & ~ntohl(upd->mask.s_addr));
93 
94 	if ((ifa = mib_create_ifa(upd->ifindex, upd->addr, upd->mask, bcast)) == NULL)
95 		return (SNMP_ERR_GENERR);
96 
97 	upd->rb |= RB_CREATE;
98 	return (SNMP_ERR_NOERROR);
99 }
100 
101 /*
102  * Modify the netmask or broadcast address. The ifindex cannot be
103  * changed (obviously).
104  */
105 static int
106 modify(struct update *upd, struct mibifa *ifa)
107 {
108 	struct mibif *ifp;
109 
110 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL)
111 		return (SNMP_ERR_WRONG_VALUE);
112 	if ((upd->set & UPD_IFINDEX) && upd->ifindex != ifa->ifindex)
113 		return (SNMP_ERR_INCONS_VALUE);
114 
115 	upd->rb_mask = ifa->inmask;
116 	upd->rb_bcast = ifa->inbcast;
117 	if (((upd->set & UPD_MASK) && upd->mask.s_addr != ifa->inmask.s_addr) ||
118 	    (upd->set & UPD_BCAST)) {
119 		if (upd->set & UPD_MASK)
120 			ifa->inmask = upd->mask;
121 		if (upd->set & UPD_BCAST) {
122 			ifa->inbcast.s_addr = ifa->inaddr.s_addr
123 			    & ifa->inmask.s_addr;
124 			if (upd->bcast)
125 				ifa->inbcast.s_addr |= 0xffffffff
126 				    & ~ifa->inmask.s_addr;
127 		}
128 		if (mib_modify_ifa(ifa)) {
129 			syslog(LOG_ERR, "set netmask/bcast: %m");
130 			ifa->inmask = upd->rb_mask;
131 			ifa->inbcast = upd->rb_bcast;
132 			mib_unmodify_ifa(ifa);
133 			return (SNMP_ERR_GENERR);
134 		}
135 		upd->rb |= RB_MODIFY;
136 	}
137 	return (SNMP_ERR_NOERROR);
138 }
139 
140 /*
141  * Destroy the given row in the table. We remove the address from the
142  * system, but keep the structure around for the COMMIT. It's deleted
143  * only in the FINISH operation.
144  */
145 static int
146 destroy(struct snmp_context *ctx __unused, struct update *upd,
147     struct mibifa *ifa)
148 {
149 	if (mib_destroy_ifa(ifa))
150 		return (SNMP_ERR_GENERR);
151 	upd->rb |= RB_DESTROY;
152 	return (SNMP_ERR_NOERROR);
153 }
154 
155 /*
156  * This function is called to commit/rollback a SET on an IpAddrEntry
157  */
158 static int
159 update_func(struct snmp_context *ctx, struct snmp_dependency *dep,
160     enum snmp_depop op)
161 {
162 	struct update *upd = (struct update *)dep;
163 	struct mibifa *ifa;
164 
165 	switch (op) {
166 
167 	  case SNMP_DEPOP_COMMIT:
168 		if ((ifa = mib_find_ifa(upd->addr)) == NULL) {
169 			/* non existing entry - must have ifindex */
170 			if (!(upd->set & UPD_IFINDEX))
171 				return (SNMP_ERR_INCONS_NAME);
172 			return (create(upd));
173 		}
174 		/* existing entry */
175 		if ((upd->set & UPD_IFINDEX) && upd->ifindex == 0) {
176 			/* delete */
177 			return (destroy(ctx, upd, ifa));
178 		}
179 		/* modify entry */
180 		return (modify(upd, ifa));
181 
182 	  case SNMP_DEPOP_ROLLBACK:
183 		if ((ifa = mib_find_ifa(upd->addr)) == NULL) {
184 			/* ups */
185 			mib_iflist_bad = 1;
186 			return (SNMP_ERR_NOERROR);
187 		}
188 		if (upd->rb & RB_CREATE) {
189 			mib_uncreate_ifa(ifa);
190 			return (SNMP_ERR_NOERROR);
191 		}
192 		if (upd->rb & RB_DESTROY) {
193 			mib_undestroy_ifa(ifa);
194 			return (SNMP_ERR_NOERROR);
195 		}
196 		if (upd->rb & RB_MODIFY) {
197 			ifa->inmask = upd->rb_mask;
198 			ifa->inbcast = upd->rb_bcast;
199 			mib_unmodify_ifa(ifa);
200 			return (SNMP_ERR_NOERROR);
201 		}
202 		return (SNMP_ERR_NOERROR);
203 
204 	  case SNMP_DEPOP_FINISH:
205 		if ((upd->rb & RB_DESTROY) &&
206 		    (ifa = mib_find_ifa(upd->addr)) != NULL &&
207 		    (ifa->flags & MIBIFA_DESTROYED)) {
208 			TAILQ_REMOVE(&mibifa_list, ifa, link);
209 			free(ifa);
210 		}
211 		return (SNMP_ERR_NOERROR);
212 	}
213 	abort();
214 }
215 
216 /**********************************************************************/
217 /*
218  * ACTION
219  */
220 int
221 op_ipaddr(struct snmp_context *ctx, struct snmp_value *value,
222     u_int sub, u_int iidx, enum snmp_op op)
223 {
224 	asn_subid_t which;
225 	struct mibifa *ifa;
226 	struct update *upd;
227 	struct asn_oid idx;
228 	u_char ipaddr[4];
229 
230 	which = value->var.subs[sub - 1];
231 
232 	ifa = NULL;
233 
234 	switch (op) {
235 
236 	  case SNMP_OP_GETNEXT:
237 		if ((ifa = NEXT_OBJECT_OID(&mibifa_list, &value->var, sub)) == NULL)
238 			return (SNMP_ERR_NOSUCHNAME);
239 		index_append(&value->var, sub, &ifa->index);
240 		break;
241 
242 	  case SNMP_OP_GET:
243 		if ((ifa = FIND_OBJECT_OID(&mibifa_list, &value->var, sub)) == NULL)
244 			return (SNMP_ERR_NOSUCHNAME);
245 		break;
246 
247 	  case SNMP_OP_SET:
248 		if (index_decode(&value->var, sub, iidx, ipaddr))
249 			return (SNMP_ERR_NO_CREATION);
250 		ifa = FIND_OBJECT_OID(&mibifa_list, &value->var, sub);
251 		idx.len = 4;
252 		idx.subs[0] = ipaddr[0];
253 		idx.subs[1] = ipaddr[1];
254 		idx.subs[2] = ipaddr[2];
255 		idx.subs[3] = ipaddr[3];
256 
257 		if ((upd = (struct update *)snmp_dep_lookup(ctx,
258 		    &oid_ipAddrTable, &idx, sizeof(*upd), update_func)) == NULL)
259 			return (SNMP_ERR_RES_UNAVAIL);
260 
261 		upd->addr.s_addr = htonl((ipaddr[0] << 24) | (ipaddr[1] << 16) |
262 		    (ipaddr[2] << 8) | (ipaddr[3] << 0));
263 
264 		switch (which) {
265 
266 		  case LEAF_ipAdEntIfIndex:
267 			if (upd->set & UPD_IFINDEX)
268 				return (SNMP_ERR_INCONS_VALUE);
269 			if (value->v.integer < 0 ||
270 			    value->v.integer > 0x07fffffff)
271 				return (SNMP_ERR_WRONG_VALUE);
272 			if (ifa != NULL) {
273 				if (ifa->ifindex != (u_int)value->v.integer &&
274 				    value->v.integer != 0)
275 					return (SNMP_ERR_INCONS_VALUE);
276 			}
277 			upd->set |= UPD_IFINDEX;
278 			upd->ifindex = (u_int)value->v.integer;
279 			break;
280 
281 		  case LEAF_ipAdEntNetMask:
282 			if (upd->set & UPD_MASK)
283 				return (SNMP_ERR_INCONS_VALUE);
284 			upd->mask.s_addr = htonl((value->v.ipaddress[0] << 24)
285 			    | (value->v.ipaddress[1] << 16)
286 			    | (value->v.ipaddress[2] << 8)
287 			    | (value->v.ipaddress[3] << 0));
288 			upd->set |= UPD_MASK;
289 			break;
290 
291 		  case LEAF_ipAdEntBcastAddr:
292 			if (upd->set & UPD_BCAST)
293 				return (SNMP_ERR_INCONS_VALUE);
294 			if (value->v.integer != 0 && value->v.integer != 1)
295 				return (SNMP_ERR_WRONG_VALUE);
296 			upd->bcast = value->v.integer;
297 			upd->set |= UPD_BCAST;
298 			break;
299 
300 		}
301 		return (SNMP_ERR_NOERROR);
302 
303 	  case SNMP_OP_ROLLBACK:
304 	  case SNMP_OP_COMMIT:
305 		return (SNMP_ERR_NOERROR);
306 	}
307 
308 	switch (which) {
309 
310 	  case LEAF_ipAdEntAddr:
311 		value->v.ipaddress[0] = ifa->index.subs[0];
312 		value->v.ipaddress[1] = ifa->index.subs[1];
313 		value->v.ipaddress[2] = ifa->index.subs[2];
314 		value->v.ipaddress[3] = ifa->index.subs[3];
315 		break;
316 
317 	  case LEAF_ipAdEntIfIndex:
318 		if (ifa->flags & MIBIFA_DESTROYED)
319 			value->v.integer = 0;
320 		else
321 			value->v.integer = ifa->ifindex;
322 		break;
323 
324 	  case LEAF_ipAdEntNetMask:
325 		value->v.ipaddress[0] = (ntohl(ifa->inmask.s_addr) >> 24) & 0xff;
326 		value->v.ipaddress[1] = (ntohl(ifa->inmask.s_addr) >> 16) & 0xff;
327 		value->v.ipaddress[2] = (ntohl(ifa->inmask.s_addr) >>  8) & 0xff;
328 		value->v.ipaddress[3] = (ntohl(ifa->inmask.s_addr) >>  0) & 0xff;
329 		break;
330 
331 	  case LEAF_ipAdEntBcastAddr:
332 		value->v.integer = ntohl(ifa->inbcast.s_addr) & 1;
333 		break;
334 
335 
336 	  case LEAF_ipAdEntReasmMaxSize:
337 		value->v.integer = 65535;
338 		break;
339 	}
340 	return (SNMP_ERR_NOERROR);
341 }
342