xref: /illumos-gate/usr/src/cmd/cmd-inet/usr.lib/inetd/contracts.c (revision 88f8b78a88cbdc6d8c1af5c3e54bc49d25095c98)
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 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <assert.h>
30 #include <errno.h>
31 #include <libintl.h>
32 #include <sys/wait.h>
33 #include <sys/ctfs.h>
34 #include <sys/contract/process.h>
35 #include <libcontract.h>
36 #include <libcontract_priv.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include "inetd_impl.h"
41 
42 
43 /* paths/filenames of contract related files */
44 #define	CONTRACT_ROOT_PATH	CTFS_ROOT "/process/"
45 #define	CONTRACT_TEMPLATE_PATH  CONTRACT_ROOT_PATH "template"
46 
47 static int active_tmpl_fd = -1;
48 
49 /*
50  * Creates and configures the the contract template used for all inetd's
51  * methods.
52  * Returns -1 on error, else the fd of the created template.
53  */
54 static int
55 create_contract_template(void)
56 {
57 	int		fd;
58 	int		err;
59 
60 	debug_msg("Entering create_contract_template");
61 
62 	if ((fd = open(CONTRACT_TEMPLATE_PATH, O_RDWR)) == -1) {
63 		error_msg(gettext("Failed to open contract file %s: %s"),
64 		    CONTRACT_TEMPLATE_PATH, strerror(errno));
65 		return (-1);
66 	}
67 
68 	/*
69 	 * Make contract inheritable and make hardware errors fatal.
70 	 * We also limit the scope of fatal events to the process
71 	 * group.  In order of preference we would have contract-aware
72 	 * login services or a property indicating which services need
73 	 * such scoping, but for the time being we'll assume that most
74 	 * non login-style services run in a single process group.
75 	 */
76 	if (((err = ct_pr_tmpl_set_param(fd,
77 	    CT_PR_INHERIT|CT_PR_PGRPONLY)) != 0) ||
78 	    ((err = ct_pr_tmpl_set_fatal(fd, CT_PR_EV_HWERR)) != 0) ||
79 	    ((err = ct_tmpl_set_critical(fd, 0)) != 0) ||
80 	    ((err = ct_tmpl_set_informative(fd, 0)) != 0)) {
81 		error_msg(gettext(
82 		    "Failed to set parameter for contract template: %s"),
83 		    strerror(err));
84 		(void) close(fd);
85 		return (-1);
86 	}
87 
88 	return (fd);
89 }
90 
91 /* Returns -1 on error, else 0. */
92 int
93 contract_init(void)
94 {
95 	debug_msg("Entering contract_init");
96 
97 	if ((active_tmpl_fd = create_contract_template()) == -1) {
98 		error_msg(gettext("Failed to create contract template"));
99 		return (-1);
100 	}
101 	return (0);
102 }
103 
104 void
105 contract_fini(void)
106 {
107 	debug_msg("Entering contract_fini");
108 
109 	if (active_tmpl_fd != -1) {
110 		(void) close(active_tmpl_fd);
111 		active_tmpl_fd = -1;
112 	}
113 }
114 
115 /*
116  * To be called directly before a service method is forked, this function
117  * results in the method process being in a new contract based on the active
118  * contract template.
119  */
120 int
121 contract_prefork(void)
122 {
123 	int err;
124 
125 	debug_msg("Entering contract_prefork");
126 
127 	if ((err = ct_tmpl_activate(active_tmpl_fd)) != 0) {
128 		error_msg(gettext("Failed to activate contract template: %s"),
129 		    strerror(err));
130 		return (-1);
131 	}
132 	return (0);
133 }
134 
135 /*
136  * To be called in both processes directly after a service method is forked,
137  * this function results in switching off contract creation for any
138  * forks done by either process, unless contract_prefork() is called beforehand.
139  */
140 void
141 contract_postfork(void)
142 {
143 	int err;
144 
145 	debug_msg("Entering contract_postfork");
146 
147 	if ((err = ct_tmpl_clear(active_tmpl_fd)) != 0)
148 		error_msg("Failed to clear active contract template: %s",
149 		    strerror(err));
150 }
151 
152 /*
153  * Fetch the latest created contract id into the space referenced by 'cid'.
154  * Returns -1 on error, else 0.
155  */
156 int
157 get_latest_contract(ctid_t *cid)
158 {
159 	debug_msg("Entering get_latest_contract");
160 
161 	if ((errno = contract_latest(cid)) != 0) {
162 		error_msg(gettext("Failed to get new contract's id: %s"),
163 		    strerror(errno));
164 		return (-1);
165 	}
166 
167 	return (0);
168 }
169 
170 /* Returns -1 on error (with errno set), else fd. */
171 static int
172 open_contract_ctl_file(ctid_t cid)
173 {
174 	debug_msg("Entering open_contract_ctl_file");
175 
176 	return (contract_open(cid, "process", "ctl", O_WRONLY));
177 }
178 
179 /*
180  * Adopt a contract.  Emits an error message and returns -1 on failure, else
181  * 0.
182  */
183 int
184 adopt_contract(ctid_t ctid, const char *fmri)
185 {
186 	int fd;
187 	int err;
188 	int ret = 0;
189 
190 	debug_msg("Entering adopt_contract, id: %d", ctid);
191 
192 	if ((fd = open_contract_ctl_file(ctid)) == -1) {
193 		if (errno == EACCES || errno == ENOENT) {
194 			/*
195 			 * We must not have inherited this contract.  That can
196 			 * happen if we were disabled and restarted.
197 			 */
198 			debug_msg("Could not adopt contract %ld for %s "
199 			    "(could not open ctl file: permission denied).\n",
200 			    ctid, fmri);
201 			return (-1);
202 		}
203 
204 		error_msg(gettext("Could not adopt contract id %ld registered "
205 		    "with %s (could not open ctl file: %s).  Events will be "
206 		    "ignored."), ctid, fmri, strerror(errno));
207 		return (-1);
208 	}
209 
210 	if ((err = ct_ctl_adopt(fd)) != 0) {
211 		error_msg(gettext("Could not adopt contract id %ld registered "
212 		    "with %s (%s).  Events will be ignored."), ctid, fmri,
213 		    strerror(err));
214 		ret = -1;
215 	}
216 
217 	err = close(fd);
218 	if (err != 0)
219 		error_msg(gettext("Could not close file descriptor %d."), fd);
220 
221 	return (ret);
222 }
223 
224 /* Returns -1 on error, else 0. */
225 int
226 abandon_contract(ctid_t ctid)
227 {
228 	int fd;
229 	int err;
230 
231 	debug_msg("Entering abandon_contract, id: %d", ctid);
232 
233 	assert(ctid != -1);
234 
235 	if ((fd = open_contract_ctl_file(ctid)) == -1) {
236 		error_msg(gettext("Failed to abandon contract %d: %s"), ctid,
237 		    strerror(errno));
238 		return (-1);
239 	}
240 
241 	if ((err = ct_ctl_abandon(fd)) != 0) {
242 		(void) close(fd);
243 		error_msg(gettext("Failed to abandon contract %d: %s"), ctid,
244 		    strerror(err));
245 		return (-1);
246 	}
247 
248 	(void) close(fd);
249 
250 	return (0);
251 }
252