xref: /freebsd/contrib/bsnmp/snmp_mibII/mibII_ipaddr.c (revision 3642298923e528d795e3a30ec165d2b469e28b40)
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 1.9 2004/08/06 08:47:02 brandt 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 		bcast.s_addr |= htonl(0xffffffff & ~ntohl(upd->mask.s_addr));
89 
90 	if ((ifa = mib_create_ifa(upd->ifindex, upd->addr, upd->mask, bcast)) == NULL)
91 		return (SNMP_ERR_GENERR);
92 
93 	upd->rb |= RB_CREATE;
94 	return (SNMP_ERR_NOERROR);
95 }
96 
97 /*
98  * Modify the netmask or broadcast address. The ifindex cannot be
99  * changed (obviously).
100  */
101 static int
102 modify(struct update *upd, struct mibifa *ifa)
103 {
104 	struct mibif *ifp;
105 
106 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL)
107 		return (SNMP_ERR_WRONG_VALUE);
108 	if ((upd->set & UPD_IFINDEX) && upd->ifindex != ifa->ifindex)
109 		return (SNMP_ERR_INCONS_VALUE);
110 
111 	upd->rb_mask = ifa->inmask;
112 	upd->rb_bcast = ifa->inbcast;
113 	if (((upd->set & UPD_MASK) && upd->mask.s_addr != ifa->inmask.s_addr) ||
114 	    (upd->set & UPD_BCAST)) {
115 		if (upd->set & UPD_MASK)
116 			ifa->inmask = upd->mask;
117 		if (upd->set & UPD_BCAST) {
118 			ifa->inbcast.s_addr = ifa->inaddr.s_addr
119 			    & ifa->inmask.s_addr;
120 			if (upd->bcast)
121 				ifa->inbcast.s_addr |= 0xffffffff
122 				    & ~ifa->inmask.s_addr;
123 		}
124 		if (mib_modify_ifa(ifa)) {
125 			syslog(LOG_ERR, "set netmask/bcast: %m");
126 			ifa->inmask = upd->rb_mask;
127 			ifa->inbcast = upd->rb_bcast;
128 			mib_unmodify_ifa(ifa);
129 			return (SNMP_ERR_GENERR);
130 		}
131 		upd->rb |= RB_MODIFY;
132 	}
133 	return (SNMP_ERR_NOERROR);
134 }
135 
136 /*
137  * Destroy the given row in the table. We remove the address from the
138  * system, but keep the structure around for the COMMIT. It's deleted
139  * only in the FINISH operation.
140  */
141 static int
142 destroy(struct snmp_context *ctx __unused, struct update *upd,
143     struct mibifa *ifa)
144 {
145 	if (mib_destroy_ifa(ifa))
146 		return (SNMP_ERR_GENERR);
147 	upd->rb |= RB_DESTROY;
148 	return (SNMP_ERR_NOERROR);
149 }
150 
151 /*
152  * This function is called to commit/rollback a SET on an IpAddrEntry
153  */
154 static int
155 update_func(struct snmp_context *ctx, struct snmp_dependency *dep,
156     enum snmp_depop op)
157 {
158 	struct update *upd = (struct update *)dep;
159 	struct mibifa *ifa;
160 
161 	switch (op) {
162 
163 	  case SNMP_DEPOP_COMMIT:
164 		if ((ifa = mib_find_ifa(upd->addr)) == NULL) {
165 			/* non existing entry - must have ifindex */
166 			if (!(upd->set & UPD_IFINDEX))
167 				return (SNMP_ERR_INCONS_NAME);
168 			return (create(upd));
169 		}
170 		/* existing entry */
171 		if ((upd->set & UPD_IFINDEX) && upd->ifindex == 0) {
172 			/* delete */
173 			return (destroy(ctx, upd, ifa));
174 		}
175 		/* modify entry */
176 		return (modify(upd, ifa));
177 
178 	  case SNMP_DEPOP_ROLLBACK:
179 		if ((ifa = mib_find_ifa(upd->addr)) == NULL) {
180 			/* ups */
181 			mib_iflist_bad = 1;
182 			return (SNMP_ERR_NOERROR);
183 		}
184 		if (upd->rb & RB_CREATE) {
185 			mib_uncreate_ifa(ifa);
186 			return (SNMP_ERR_NOERROR);
187 		}
188 		if (upd->rb & RB_DESTROY) {
189 			mib_undestroy_ifa(ifa);
190 			return (SNMP_ERR_NOERROR);
191 		}
192 		if (upd->rb & RB_MODIFY) {
193 			ifa->inmask = upd->rb_mask;
194 			ifa->inbcast = upd->rb_bcast;
195 			mib_unmodify_ifa(ifa);
196 			return (SNMP_ERR_NOERROR);
197 		}
198 		return (SNMP_ERR_NOERROR);
199 
200 	  case SNMP_DEPOP_FINISH:
201 		if ((upd->rb & RB_DESTROY) &&
202 		    (ifa = mib_find_ifa(upd->addr)) != NULL &&
203 		    (ifa->flags & MIBIFA_DESTROYED)) {
204 			TAILQ_REMOVE(&mibifa_list, ifa, link);
205 			free(ifa);
206 		}
207 		return (SNMP_ERR_NOERROR);
208 	}
209 	abort();
210 }
211 
212 /**********************************************************************/
213 /*
214  * ACTION
215  */
216 int
217 op_ipaddr(struct snmp_context *ctx, struct snmp_value *value,
218     u_int sub, u_int iidx, enum snmp_op op)
219 {
220 	asn_subid_t which;
221 	struct mibifa *ifa;
222 	struct update *upd;
223 	struct asn_oid idx;
224 	u_char ipaddr[4];
225 
226 	which = value->var.subs[sub - 1];
227 
228 	ifa = NULL;
229 
230 	switch (op) {
231 
232 	  case SNMP_OP_GETNEXT:
233 		if ((ifa = NEXT_OBJECT_OID(&mibifa_list, &value->var, sub)) == NULL)
234 			return (SNMP_ERR_NOSUCHNAME);
235 		index_append(&value->var, sub, &ifa->index);
236 		break;
237 
238 	  case SNMP_OP_GET:
239 		if ((ifa = FIND_OBJECT_OID(&mibifa_list, &value->var, sub)) == NULL)
240 			return (SNMP_ERR_NOSUCHNAME);
241 		break;
242 
243 	  case SNMP_OP_SET:
244 		if (index_decode(&value->var, sub, iidx, ipaddr))
245 			return (SNMP_ERR_NO_CREATION);
246 		ifa = FIND_OBJECT_OID(&mibifa_list, &value->var, sub);
247 		idx.len = 4;
248 		idx.subs[0] = ipaddr[0];
249 		idx.subs[1] = ipaddr[1];
250 		idx.subs[2] = ipaddr[2];
251 		idx.subs[3] = ipaddr[3];
252 
253 		if ((upd = (struct update *)snmp_dep_lookup(ctx,
254 		    &oid_ipAddrTable, &idx, sizeof(*upd), update_func)) == NULL)
255 			return (SNMP_ERR_RES_UNAVAIL);
256 
257 		upd->addr.s_addr = htonl((ipaddr[0] << 24) | (ipaddr[1] << 16) |
258 		    (ipaddr[2] << 8) | (ipaddr[3] << 0));
259 
260 		switch (which) {
261 
262 		  case LEAF_ipAdEntIfIndex:
263 			if (upd->set & UPD_IFINDEX)
264 				return (SNMP_ERR_INCONS_VALUE);
265 			if (value->v.integer < 0 ||
266 			    value->v.integer > 0x07fffffff)
267 				return (SNMP_ERR_WRONG_VALUE);
268 			if (ifa != NULL) {
269 				if (ifa->ifindex != (u_int)value->v.integer &&
270 				    value->v.integer != 0)
271 					return (SNMP_ERR_INCONS_VALUE);
272 			}
273 			upd->set |= UPD_IFINDEX;
274 			upd->ifindex = (u_int)value->v.integer;
275 			break;
276 
277 		  case LEAF_ipAdEntNetMask:
278 			if (upd->set & UPD_MASK)
279 				return (SNMP_ERR_INCONS_VALUE);
280 			upd->mask.s_addr = htonl((value->v.ipaddress[0] << 24)
281 			    | (value->v.ipaddress[1] << 16)
282 			    | (value->v.ipaddress[2] << 8)
283 			    | (value->v.ipaddress[3] << 0));
284 			upd->set |= UPD_MASK;
285 			break;
286 
287 		  case LEAF_ipAdEntBcastAddr:
288 			if (upd->set & UPD_BCAST)
289 				return (SNMP_ERR_INCONS_VALUE);
290 			if (value->v.integer != 0 && value->v.integer != 1)
291 				return (SNMP_ERR_WRONG_VALUE);
292 			upd->bcast = value->v.integer;
293 			upd->set |= UPD_BCAST;
294 			break;
295 
296 		}
297 		return (SNMP_ERR_NOERROR);
298 
299 	  case SNMP_OP_ROLLBACK:
300 	  case SNMP_OP_COMMIT:
301 		return (SNMP_ERR_NOERROR);
302 	}
303 
304 	switch (which) {
305 
306 	  case LEAF_ipAdEntAddr:
307 		value->v.ipaddress[0] = ifa->index.subs[0];
308 		value->v.ipaddress[1] = ifa->index.subs[1];
309 		value->v.ipaddress[2] = ifa->index.subs[2];
310 		value->v.ipaddress[3] = ifa->index.subs[3];
311 		break;
312 
313 	  case LEAF_ipAdEntIfIndex:
314 		if (ifa->flags & MIBIFA_DESTROYED)
315 			value->v.integer = 0;
316 		else
317 			value->v.integer = ifa->ifindex;
318 		break;
319 
320 	  case LEAF_ipAdEntNetMask:
321 		value->v.ipaddress[0] = (ntohl(ifa->inmask.s_addr) >> 24) & 0xff;
322 		value->v.ipaddress[1] = (ntohl(ifa->inmask.s_addr) >> 16) & 0xff;
323 		value->v.ipaddress[2] = (ntohl(ifa->inmask.s_addr) >>  8) & 0xff;
324 		value->v.ipaddress[3] = (ntohl(ifa->inmask.s_addr) >>  0) & 0xff;
325 		break;
326 
327 	  case LEAF_ipAdEntBcastAddr:
328 		value->v.integer = ntohl(ifa->inbcast.s_addr) & 1;
329 		break;
330 
331 
332 	  case LEAF_ipAdEntReasmMaxSize:
333 		value->v.integer = 65535;
334 		break;
335 	}
336 	return (SNMP_ERR_NOERROR);
337 }
338