xref: /titanic_41/usr/src/uts/common/inet/snmpcom.c (revision 6451fdbca2f79129a3a09d2fe3f6dd4d062bebff)
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 2005 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 #include <inet/ip.h>
55 #include <inet/ip6.h>
56 #include <inet/tcp.h>
57 #include <inet/udp_impl.h>
58 
59 #define	DEFAULT_LENGTH	sizeof (long)
60 #define	DATA_MBLK_SIZE	1024
61 #define	TOAHDR_SIZE	(sizeof (struct T_optmgmt_ack) +\
62 	sizeof (struct opthdr))
63 
64 /* SNMP Option Request Structure */
65 typedef struct sor_s {
66 	int	sor_group;
67 	int	sor_code;		/* MIB2 index value */
68 	int	sor_size;
69 } sor_t;
70 
71 /*
72  * Validation Table for set requests.
73  */
74 static sor_t	req_arr[] = {
75 	{ MIB2_IP,	1,	sizeof (int)			},
76 	{ MIB2_IP,	2,	sizeof (int)			},
77 	{ MIB2_IP,	21,	sizeof (mib2_ipRouteEntry_t)	},
78 	{ MIB2_IP,	22,	sizeof (mib2_ipNetToMediaEntry_t)},
79 	{ MIB2_TCP,	13,	sizeof (mib2_tcpConnEntry_t)	}
80 };
81 
82 /*
83  * Binary compatibility to what used to be T_CURRENT in older releases.
84  * Unfortunately, the binary chosen for it was different and used by
85  * T_PARTSUCCESS in the new name space. However T_PARTSUCESS is only
86  * anticiapted in new T_OPTMGM_REQ (and not O_T_OPTMGMT_REQ messages).
87  * Only a test for TBADFLAG which uses one of the MIB option levels
88  * may have trouble with this provision for binary compatibility.
89  */
90 #define	OLD_T_CURRENT	0x100	/* same value as T_PARTSUCCESS */
91 
92 /*
93  * MIB info returned in data part of M_PROTO msg.  All info for a single
94  * request is appended in a chain of mblk's off of the M_PROTO T_OPTMGMT_ACK
95  * ctl buffer.
96  */
97 int
98 snmp_append_data(mblk_t *mpdata, char *blob, int len)
99 {
100 
101 	if (!mpdata)
102 		return (0);
103 	while (mpdata->b_cont)
104 		mpdata = mpdata->b_cont;
105 	if (mpdata->b_wptr + len >= mpdata->b_datap->db_lim) {
106 		mpdata->b_cont = allocb(DATA_MBLK_SIZE, BPRI_HI);
107 		mpdata = mpdata->b_cont;
108 		if (!mpdata)
109 			return (0);
110 	}
111 	bcopy(blob, (char *)mpdata->b_wptr, len);
112 	mpdata->b_wptr += len;
113 	return (1);
114 }
115 
116 /*
117  * Need a form which avoids O(n^2) behavior locating the end of the
118  * chain every time.  This is it.
119  */
120 int
121 snmp_append_data2(mblk_t *mpdata, mblk_t **last_mpp, char *blob, int len)
122 {
123 
124 	if (!mpdata)
125 		return (0);
126 	if (*last_mpp == NULL) {
127 		while (mpdata->b_cont)
128 			mpdata = mpdata->b_cont;
129 		*last_mpp = mpdata;
130 	}
131 	if ((*last_mpp)->b_wptr + len >= (*last_mpp)->b_datap->db_lim) {
132 		(*last_mpp)->b_cont = allocb(DATA_MBLK_SIZE, BPRI_HI);
133 		*last_mpp = (*last_mpp)->b_cont;
134 		if (!*last_mpp)
135 			return (0);
136 	}
137 	bcopy(blob, (char *)(*last_mpp)->b_wptr, len);
138 	(*last_mpp)->b_wptr += len;
139 	return (1);
140 }
141 
142 /*
143  * SNMP requests are issued using putmsg() on a stream containing all
144  * relevant modules.  The ctl part contains a O_T_OPTMGMT_REQ message,
145  * and the data part is NULL
146  * to process this msg. If snmpcom_req() returns FALSE, then the module
147  * will try optcom_req to see if its some sort of SOCKET or IP option.
148  * snmpcom_req returns TRUE whenever the first option is recognized as
149  * an SNMP request, even if a bad one.
150  *
151  * "get" is done by a single O_T_OPTMGMT_REQ with MGMT_flags set to T_CURRENT.
152  * All modules respond with one or msg's about what they know.  Responses
153  * are in T_OPTMGMT_ACK format.  The opthdr level/name fields identify what
154  * is begin returned, the len field how big it is (in bytes).  The info
155  * itself is in the data portion of the msg.  Fixed length info returned
156  * in one msg; each table in a separate msg.
157  *
158  * setfn() returns 1 if things ok, 0 if set request invalid or otherwise
159  * messed up.
160  *
161  * If the passed q is at the bottom of the module chain (q_next == NULL,
162  * a ctl msg with req->name, level, len all zero is sent upstream.  This
163  * is and EOD flag to the caller.
164  *
165  * IMPORTANT:
166  * - The msg type is M_PROTO, not M_PCPROTO!!!  This is by design,
167  *   since multiple messages will be sent to stream head and we want
168  *   them queued for reading, not discarded.
169  * - All requests which match a table entry are sent to all get/set functions
170  *   of each module.  The functions must simply ignore requests not meant
171  *   for them: getfn() returns 0, setfn() returns 1.
172  */
173 boolean_t
174 snmpcom_req(queue_t *q, mblk_t *mp, pfi_t setfn, pfi_t getfn, cred_t *credp)
175 {
176 	mblk_t			*mpctl;
177 	struct opthdr		*req;
178 	struct opthdr		*next_req;
179 	struct opthdr		*req_end;
180 	struct opthdr		*req_start;
181 	sor_t			*sreq;
182 	struct T_optmgmt_req	*tor = (struct T_optmgmt_req *)mp->b_rptr;
183 	struct T_optmgmt_ack	*toa;
184 	boolean_t		pass_to_ip = B_FALSE;
185 
186 	if (mp->b_cont) {	/* don't deal with multiple mblk's */
187 		freemsg(mp->b_cont);
188 		mp->b_cont = (mblk_t *)0;
189 		optcom_err_ack(q, mp, TSYSERR, EBADMSG);
190 		return (B_TRUE);
191 	}
192 	if ((mp->b_wptr - mp->b_rptr) < sizeof (struct T_optmgmt_req) ||
193 	    !(req_start = (struct opthdr *)mi_offset_param(mp,
194 		tor->OPT_offset, tor->OPT_length)))
195 		goto bad_req1;
196 	if (! __TPI_OPT_ISALIGNED(req_start))
197 		goto bad_req1;
198 
199 	/*
200 	 * if first option not in the MIB2 or EXPER range, return false so
201 	 * optcom_req can scope things out.  Otherwise it's passed to each
202 	 * calling module to process or ignore as it sees fit.
203 	 */
204 	if ((!(req_start->level >= MIB2_RANGE_START &&
205 			req_start->level <= MIB2_RANGE_END)) &&
206 	    (!(req_start->level >= EXPER_RANGE_START &&
207 			req_start->level <= EXPER_RANGE_END)))
208 		return (B_FALSE);
209 
210 	if (setfn == tcp_snmp_set || setfn == udp_snmp_set ||
211 	    getfn == tcp_snmp_get || getfn == udp_snmp_get)
212 		pass_to_ip = B_TRUE;
213 
214 	switch (tor->MGMT_flags) {
215 
216 	case T_NEGOTIATE:
217 		if (secpolicy_net_config(credp, B_FALSE) != 0) {
218 			optcom_err_ack(q, mp, TACCES, 0);
219 			return (B_TRUE);
220 		}
221 		req_end = (struct opthdr *)((uchar_t *)req_start +
222 			tor->OPT_length);
223 		for (req = req_start; req < req_end; req = next_req) {
224 			next_req =
225 				(struct opthdr *)((uchar_t *)&req[1] +
226 				_TPI_ALIGN_OPT(req->len));
227 			if (next_req > req_end)
228 				goto bad_req2;
229 			for (sreq = req_arr; sreq < A_END(req_arr); sreq++) {
230 				if (req->level == sreq->sor_group &&
231 				    req->name == sreq->sor_code)
232 					break;
233 			}
234 			if (sreq >= A_END(req_arr))
235 				goto bad_req3;
236 			if (!(*setfn)(q, req->level, req->name,
237 				(uchar_t *)&req[1], req->len))
238 				goto bad_req4;
239 		}
240 		if (q->q_next != NULL)
241 			putnext(q, mp);
242 		else if (pass_to_ip)
243 			ip_output(Q_TO_CONN(q), mp, q, IP_WPUT);
244 		else
245 			freemsg(mp);
246 		return (B_TRUE);
247 
248 	case OLD_T_CURRENT:
249 	case T_CURRENT:
250 		mpctl = allocb(TOAHDR_SIZE, BPRI_MED);
251 		if (!mpctl) {
252 			optcom_err_ack(q, mp, TSYSERR, ENOMEM);
253 			return (B_TRUE);
254 		}
255 		mpctl->b_cont = allocb(DATA_MBLK_SIZE, BPRI_MED);
256 		if (!mpctl->b_cont) {
257 			freemsg(mpctl);
258 			optcom_err_ack(q, mp, TSYSERR, ENOMEM);
259 			return (B_TRUE);
260 		}
261 		mpctl->b_datap->db_type = M_PROTO;
262 		mpctl->b_wptr += TOAHDR_SIZE;
263 		toa = (struct T_optmgmt_ack *)mpctl->b_rptr;
264 		toa->PRIM_type = T_OPTMGMT_ACK;
265 		toa->OPT_offset = sizeof (struct T_optmgmt_ack);
266 		toa->OPT_length = sizeof (struct opthdr);
267 		toa->MGMT_flags = T_SUCCESS;
268 		if (!(*getfn)(q, mpctl))
269 			freemsg(mpctl);
270 		/*
271 		 * all data for this module has now been sent upstream.  If
272 		 * this is bottom module of stream, send up an EOD ctl msg,
273 		 * otherwise pass onto the next guy for processing.
274 		 */
275 		if (q->q_next != NULL) {
276 			putnext(q, mp);
277 			return (B_TRUE);
278 		} else if (pass_to_ip) {
279 			ip_output(Q_TO_CONN(q), mp, q, IP_WPUT);
280 			return (B_TRUE);
281 		}
282 		if (mp->b_cont) {
283 			freemsg(mp->b_cont);
284 			mp->b_cont = NULL;
285 		}
286 		mpctl = reallocb(mp, TOAHDR_SIZE, 1);
287 		if (!mpctl) {
288 			optcom_err_ack(q, mp, TSYSERR, ENOMEM);
289 			return (B_TRUE);
290 		}
291 		mpctl->b_datap->db_type = M_PROTO;
292 		mpctl->b_wptr = mpctl->b_rptr + TOAHDR_SIZE;
293 		toa = (struct T_optmgmt_ack *)mpctl->b_rptr;
294 		toa->PRIM_type = T_OPTMGMT_ACK;
295 		toa->OPT_offset = sizeof (struct T_optmgmt_ack);
296 		toa->OPT_length = sizeof (struct opthdr);
297 		toa->MGMT_flags = T_SUCCESS;
298 		req = (struct opthdr *)&toa[1];
299 		req->level = 0;
300 		req->name = 0;
301 		req->len = 0;
302 		qreply(q, mpctl);
303 		return (B_TRUE);
304 
305 	default:
306 		optcom_err_ack(q, mp, TBADFLAG, 0);
307 		return (B_TRUE);
308 	}
309 
310 bad_req1:;
311 	printf("snmpcom bad_req1\n");
312 	goto bad_req;
313 bad_req2:;
314 	printf("snmpcom bad_req2\n");
315 	goto bad_req;
316 bad_req3:;
317 	printf("snmpcom bad_req3\n");
318 	goto bad_req;
319 bad_req4:;
320 	printf("snmpcom bad_req4\n");
321 	/* FALLTHRU */
322 bad_req:;
323 	optcom_err_ack(q, mp, TBADOPT, 0);
324 	return (B_TRUE);
325 
326 }
327