xref: /titanic_50/usr/src/uts/common/inet/snmpcom.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 1992,1997-2003 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 /* Copyright (c) 1990 Mentat Inc. */
27 
28 #pragma ident	"%Z%%M%	%I%	%E% SMI"
29 
30 /*
31  * This file contains common code for handling Options Management requests
32  * for SNMP/MIB.
33  */
34 
35 #include <sys/types.h>
36 #include <sys/stream.h>
37 #include <sys/stropts.h>
38 #include <sys/errno.h>
39 #define	_SUN_TPI_VERSION 2
40 #include <sys/tihdr.h>
41 #include <sys/ddi.h>
42 #include <sys/cmn_err.h>
43 #include <sys/policy.h>
44 
45 #include <sys/socket.h>
46 #include <netinet/in.h>
47 
48 #include <inet/common.h>
49 #include <inet/mi.h>
50 #include <inet/mib2.h>
51 #include <inet/optcom.h>
52 #include <inet/snmpcom.h>
53 
54 #define	DEFAULT_LENGTH	sizeof (long)
55 #define	DATA_MBLK_SIZE	1024
56 #define	TOAHDR_SIZE	(sizeof (struct T_optmgmt_ack) +\
57 	sizeof (struct opthdr))
58 
59 /* SNMP Option Request Structure */
60 typedef struct sor_s {
61 	int	sor_group;
62 	int	sor_code;		/* MIB2 index value */
63 	int	sor_size;
64 } sor_t;
65 
66 /*
67  * Validation Table for set requests.
68  */
69 static sor_t	req_arr[] = {
70 	{ MIB2_IP,	1,	sizeof (int)			},
71 	{ MIB2_IP,	2,	sizeof (int)			},
72 	{ MIB2_IP,	21,	sizeof (mib2_ipRouteEntry_t)	},
73 	{ MIB2_IP,	22,	sizeof (mib2_ipNetToMediaEntry_t)},
74 	{ MIB2_TCP,	13,	sizeof (mib2_tcpConnEntry_t)	}
75 };
76 
77 /*
78  * Binary compatibility to what used to be T_CURRENT in older releases.
79  * Unfortunately, the binary chosen for it was different and used by
80  * T_PARTSUCCESS in the new name space. However T_PARTSUCESS is only
81  * anticiapted in new T_OPTMGM_REQ (and not O_T_OPTMGMT_REQ messages).
82  * Only a test for TBADFLAG which uses one of the MIB option levels
83  * may have trouble with this provision for binary compatibility.
84  */
85 #define	OLD_T_CURRENT	0x100	/* same value as T_PARTSUCCESS */
86 
87 /*
88  * MIB info returned in data part of M_PROTO msg.  All info for a single
89  * request is appended in a chain of mblk's off of the M_PROTO T_OPTMGMT_ACK
90  * ctl buffer.
91  */
92 int
93 snmp_append_data(mpdata, blob, len)
94 	mblk_t	*mpdata;
95 	char	*blob;
96 	int	len;
97 {
98 
99 	if (!mpdata)
100 		return (0);
101 	while (mpdata->b_cont)
102 		mpdata = mpdata->b_cont;
103 	if (mpdata->b_wptr + len >= mpdata->b_datap->db_lim) {
104 		mpdata->b_cont = allocb(DATA_MBLK_SIZE, BPRI_HI);
105 		mpdata = mpdata->b_cont;
106 		if (!mpdata)
107 			return (0);
108 	}
109 	bcopy(blob, (char *)mpdata->b_wptr, len);
110 	mpdata->b_wptr += len;
111 	return (1);
112 }
113 
114 /*
115  * Need a form which avoids O(n^2) behavior locating the end of the
116  * chain every time.  This is it.
117  */
118 int
119 snmp_append_data2(mblk_t *mpdata, mblk_t **last_mpp, char *blob, int len)
120 {
121 
122 	if (!mpdata)
123 		return (0);
124 	if (*last_mpp == NULL) {
125 		while (mpdata->b_cont)
126 			mpdata = mpdata->b_cont;
127 		*last_mpp = mpdata;
128 	}
129 	if ((*last_mpp)->b_wptr + len >= (*last_mpp)->b_datap->db_lim) {
130 		(*last_mpp)->b_cont = allocb(DATA_MBLK_SIZE, BPRI_HI);
131 		*last_mpp = (*last_mpp)->b_cont;
132 		if (!*last_mpp)
133 			return (0);
134 	}
135 	bcopy(blob, (char *)(*last_mpp)->b_wptr, len);
136 	(*last_mpp)->b_wptr += len;
137 	return (1);
138 }
139 
140 /*
141  * SNMP requests are issued using putmsg() on a stream containing all
142  * relevant modules.  The ctl part contains a O_T_OPTMGMT_REQ message,
143  * and the data part is NULL
144  * to process this msg. If snmpcom_req() returns FALSE, then the module
145  * will try optcom_req to see if its some sort of SOCKET or IP option.
146  * snmpcom_req returns TRUE whenever the first option is recognized as
147  * an SNMP request, even if a bad one.
148  *
149  * "get" is done by a single O_T_OPTMGMT_REQ with MGMT_flags set to T_CURRENT.
150  * All modules respond with one or msg's about what they know.  Responses
151  * are in T_OPTMGMT_ACK format.  The opthdr level/name fields identify what
152  * is begin returned, the len field how big it is (in bytes).  The info
153  * itself is in the data portion of the msg.  Fixed length info returned
154  * in one msg; each table in a separate msg.
155  *
156  * setfn() returns 1 if things ok, 0 if set request invalid or otherwise
157  * messed up.
158  *
159  * If the passed q is at the bottom of the module chain (q_next == NULL,
160  * a ctl msg with req->name, level, len all zero is sent upstream.  This
161  * is and EOD flag to the caller.
162  *
163  * IMPORTANT:
164  * - The msg type is M_PROTO, not M_PCPROTO!!!  This is by design,
165  *   since multiple messages will be sent to stream head and we want
166  *   them queued for reading, not discarded.
167  * - All requests which match a table entry are sent to all get/set functions
168  *   of each module.  The functions must simply ignore requests not meant
169  *   for them: getfn() returns 0, setfn() returns 1.
170  */
171 boolean_t
172 snmpcom_req(q, mp, setfn, getfn, credp)
173 	queue_t	*q;
174 	mblk_t	*mp;
175 	pfi_t	setfn;
176 	pfi_t	getfn;
177 	cred_t	*credp;
178 {
179 	mblk_t			*mpctl;
180 	struct opthdr		*req;
181 	struct opthdr		*next_req;
182 	struct opthdr		*req_end;
183 	struct opthdr		*req_start;
184 	sor_t			*sreq;
185 	struct T_optmgmt_req	*tor = (struct T_optmgmt_req *)mp->b_rptr;
186 	struct T_optmgmt_ack	*toa;
187 
188 	if (mp->b_cont) {	/* don't deal with multiple mblk's */
189 		freemsg(mp->b_cont);
190 		mp->b_cont = (mblk_t *)0;
191 		optcom_err_ack(q, mp, TSYSERR, EBADMSG);
192 		return (B_TRUE);
193 	}
194 	if ((mp->b_wptr - mp->b_rptr) < sizeof (struct T_optmgmt_req) ||
195 	    !(req_start = (struct opthdr *)mi_offset_param(mp,
196 		tor->OPT_offset, tor->OPT_length)))
197 		goto bad_req1;
198 	if (! __TPI_OPT_ISALIGNED(req_start))
199 		goto bad_req1;
200 
201 	/*
202 	 * if first option not in the MIB2 or EXPER range, return false so
203 	 * optcom_req can scope things out.  Otherwise it's passed to each
204 	 * calling module to process or ignore as it sees fit.
205 	 */
206 	if ((!(req_start->level >= MIB2_RANGE_START &&
207 			req_start->level <= MIB2_RANGE_END)) &&
208 	    (!(req_start->level >= EXPER_RANGE_START &&
209 			req_start->level <= EXPER_RANGE_END)))
210 		return (B_FALSE);
211 
212 	switch (tor->MGMT_flags) {
213 
214 	case T_NEGOTIATE:
215 		if (secpolicy_net_config(credp, B_FALSE) != 0) {
216 			optcom_err_ack(q, mp, TACCES, 0);
217 			return (B_TRUE);
218 		}
219 		req_end = (struct opthdr *)((uchar_t *)req_start +
220 			tor->OPT_length);
221 		for (req = req_start; req < req_end; req = next_req) {
222 			next_req =
223 				(struct opthdr *)((uchar_t *)&req[1] +
224 				_TPI_ALIGN_OPT(req->len));
225 			if (next_req > req_end)
226 				goto bad_req2;
227 			for (sreq = req_arr; sreq < A_END(req_arr); sreq++) {
228 				if (req->level == sreq->sor_group &&
229 				    req->name == sreq->sor_code)
230 					break;
231 			}
232 			if (sreq >= A_END(req_arr))
233 				goto bad_req3;
234 			if (!(*setfn)(q, req->level, req->name,
235 				(uchar_t *)&req[1], req->len))
236 				goto bad_req4;
237 		}
238 		if (q->q_next)
239 			putnext(q, mp);
240 		else
241 			freemsg(mp);
242 		return (B_TRUE);
243 
244 	case OLD_T_CURRENT:
245 	case T_CURRENT:
246 		mpctl = allocb(TOAHDR_SIZE, BPRI_MED);
247 		if (!mpctl) {
248 			optcom_err_ack(q, mp, TSYSERR, ENOMEM);
249 			return (B_TRUE);
250 		}
251 		mpctl->b_cont = allocb(DATA_MBLK_SIZE, BPRI_MED);
252 		if (!mpctl->b_cont) {
253 			freemsg(mpctl);
254 			optcom_err_ack(q, mp, TSYSERR, ENOMEM);
255 			return (B_TRUE);
256 		}
257 		mpctl->b_datap->db_type = M_PROTO;
258 		mpctl->b_wptr += TOAHDR_SIZE;
259 		toa = (struct T_optmgmt_ack *)mpctl->b_rptr;
260 		toa->PRIM_type = T_OPTMGMT_ACK;
261 		toa->OPT_offset = sizeof (struct T_optmgmt_ack);
262 		toa->OPT_length = sizeof (struct opthdr);
263 		toa->MGMT_flags = T_SUCCESS;
264 		if (!(*getfn)(q, mpctl))
265 			freemsg(mpctl);
266 		/*
267 		 * all data for this module has now been sent upstream.  If
268 		 * this is bottom module of stream, send up an EOD ctl msg,
269 		 * otherwise pass onto the next guy for processing.
270 		 */
271 		if (q->q_next) {
272 			putnext(q, mp);
273 			return (B_TRUE);
274 		}
275 		if (mp->b_cont) {
276 			freemsg(mp->b_cont);
277 			mp->b_cont = NULL;
278 		}
279 		mpctl = reallocb(mp, TOAHDR_SIZE, 1);
280 		if (!mpctl) {
281 			optcom_err_ack(q, mp, TSYSERR, ENOMEM);
282 			return (B_TRUE);
283 		}
284 		mpctl->b_datap->db_type = M_PROTO;
285 		mpctl->b_wptr = mpctl->b_rptr + TOAHDR_SIZE;
286 		toa = (struct T_optmgmt_ack *)mpctl->b_rptr;
287 		toa->PRIM_type = T_OPTMGMT_ACK;
288 		toa->OPT_offset = sizeof (struct T_optmgmt_ack);
289 		toa->OPT_length = sizeof (struct opthdr);
290 		toa->MGMT_flags = T_SUCCESS;
291 		req = (struct opthdr *)&toa[1];
292 		req->level = 0;
293 		req->name = 0;
294 		req->len = 0;
295 		qreply(q, mpctl);
296 		return (B_TRUE);
297 
298 	default:
299 		optcom_err_ack(q, mp, TBADFLAG, 0);
300 		return (B_TRUE);
301 	}
302 
303 bad_req1:;
304 	printf("snmpcom bad_req1\n");
305 	goto bad_req;
306 bad_req2:;
307 	printf("snmpcom bad_req2\n");
308 	goto bad_req;
309 bad_req3:;
310 	printf("snmpcom bad_req3\n");
311 	goto bad_req;
312 bad_req4:;
313 	printf("snmpcom bad_req4\n");
314 	/* FALLTHRU */
315 bad_req:;
316 	optcom_err_ack(q, mp, TBADOPT, 0);
317 	return (B_TRUE);
318 
319 }
320