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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <assert.h>
29 #include <errno.h>
30 #include <libintl.h>
31 #include <sys/wait.h>
32 #include <sys/ctfs.h>
33 #include <sys/contract/process.h>
34 #include <libcontract.h>
35 #include <libcontract_priv.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
39 #include "inetd_impl.h"
40 
41 
42 /* paths/filenames of contract related files */
43 #define	CONTRACT_ROOT_PATH	CTFS_ROOT "/process/"
44 #define	CONTRACT_TEMPLATE_PATH  CONTRACT_ROOT_PATH "template"
45 
46 static int active_tmpl_fd = -1;
47 
48 /*
49  * Creates and configures the the contract template used for all inetd's
50  * methods.
51  * Returns -1 on error, else the fd of the created template.
52  */
53 static int
create_contract_template(void)54 create_contract_template(void)
55 {
56 	int		fd;
57 	int		err;
58 
59 	if ((fd = open(CONTRACT_TEMPLATE_PATH, O_RDWR)) == -1) {
60 		error_msg(gettext("Failed to open contract file %s: %s"),
61 		    CONTRACT_TEMPLATE_PATH, strerror(errno));
62 		return (-1);
63 	}
64 
65 	/*
66 	 * Make contract inheritable and make hardware errors fatal.
67 	 * We also limit the scope of fatal events to the process
68 	 * group.  In order of preference we would have contract-aware
69 	 * login services or a property indicating which services need
70 	 * such scoping, but for the time being we'll assume that most
71 	 * non login-style services run in a single process group.
72 	 */
73 	if (((err = ct_pr_tmpl_set_param(fd,
74 	    CT_PR_INHERIT|CT_PR_PGRPONLY)) != 0) ||
75 	    ((err = ct_pr_tmpl_set_fatal(fd, CT_PR_EV_HWERR)) != 0) ||
76 	    ((err = ct_tmpl_set_critical(fd, 0)) != 0) ||
77 	    ((err = ct_tmpl_set_informative(fd, 0)) != 0)) {
78 		error_msg(gettext(
79 		    "Failed to set parameter for contract template: %s"),
80 		    strerror(err));
81 		(void) close(fd);
82 		return (-1);
83 	}
84 
85 	return (fd);
86 }
87 
88 /* Returns -1 on error, else 0. */
89 int
contract_init(void)90 contract_init(void)
91 {
92 	if ((active_tmpl_fd = create_contract_template()) == -1) {
93 		error_msg(gettext("Failed to create contract template"));
94 		return (-1);
95 	}
96 	return (0);
97 }
98 
99 void
contract_fini(void)100 contract_fini(void)
101 {
102 	if (active_tmpl_fd != -1) {
103 		(void) close(active_tmpl_fd);
104 		active_tmpl_fd = -1;
105 	}
106 }
107 
108 /*
109  * To be called directly before a service method is forked, this function
110  * results in the method process being in a new contract based on the active
111  * contract template.
112  */
113 int
contract_prefork(const char * fmri,int method)114 contract_prefork(const char *fmri, int method)
115 {
116 	int err;
117 
118 	if ((err = ct_pr_tmpl_set_svc_fmri(active_tmpl_fd, fmri)) != 0) {
119 		error_msg(gettext("Failed to set svc_fmri term: %s"),
120 		    strerror(err));
121 		return (-1);
122 	}
123 	if ((err = ct_pr_tmpl_set_svc_aux(active_tmpl_fd,
124 	    methods[method].name)) != 0) {
125 		error_msg(gettext("Failed to set svc_aux term: %s"),
126 		    strerror(err));
127 		return (-1);
128 	}
129 
130 	if ((err = ct_tmpl_activate(active_tmpl_fd)) != 0) {
131 		error_msg(gettext("Failed to activate contract template: %s"),
132 		    strerror(err));
133 		return (-1);
134 	}
135 	return (0);
136 }
137 
138 /*
139  * To be called in both processes directly after a service method is forked,
140  * this function results in switching off contract creation for any
141  * forks done by either process, unless contract_prefork() is called beforehand.
142  */
143 void
contract_postfork(void)144 contract_postfork(void)
145 {
146 	int err;
147 
148 	if ((err = ct_tmpl_clear(active_tmpl_fd)) != 0)
149 		error_msg("Failed to clear active contract template: %s",
150 		    strerror(err));
151 }
152 
153 /*
154  * Fetch the latest created contract id into the space referenced by 'cid'.
155  * Returns -1 on error, else 0.
156  */
157 int
get_latest_contract(ctid_t * cid)158 get_latest_contract(ctid_t *cid)
159 {
160 	if ((errno = contract_latest(cid)) != 0) {
161 		error_msg(gettext("Failed to get new contract's id: %s"),
162 		    strerror(errno));
163 		return (-1);
164 	}
165 
166 	return (0);
167 }
168 
169 /* Returns -1 on error (with errno set), else fd. */
170 static int
open_contract_ctl_file(ctid_t cid)171 open_contract_ctl_file(ctid_t cid)
172 {
173 	return (contract_open(cid, "process", "ctl", O_WRONLY));
174 }
175 
176 /*
177  * Adopt a contract.  Emits an error message and returns -1 on failure, else
178  * 0.
179  */
180 int
adopt_contract(ctid_t ctid,const char * fmri)181 adopt_contract(ctid_t ctid, const char *fmri)
182 {
183 	int fd;
184 	int err;
185 	int ret = 0;
186 
187 	if ((fd = open_contract_ctl_file(ctid)) == -1) {
188 		if (errno == EACCES || errno == ENOENT) {
189 			/*
190 			 * We must not have inherited this contract.  That can
191 			 * happen if we were disabled and restarted.
192 			 */
193 			debug_msg("Could not adopt contract %ld for %s "
194 			    "(could not open ctl file: permission denied).\n",
195 			    ctid, fmri);
196 			return (-1);
197 		}
198 
199 		error_msg(gettext("Could not adopt contract id %ld registered "
200 		    "with %s (could not open ctl file: %s).  Events will be "
201 		    "ignored."), ctid, fmri, strerror(errno));
202 		return (-1);
203 	}
204 
205 	if ((err = ct_ctl_adopt(fd)) != 0) {
206 		error_msg(gettext("Could not adopt contract id %ld registered "
207 		    "with %s (%s).  Events will be ignored."), ctid, fmri,
208 		    strerror(err));
209 		ret = -1;
210 	}
211 
212 	err = close(fd);
213 	if (err != 0)
214 		error_msg(gettext("Could not close file descriptor %d."), fd);
215 
216 	return (ret);
217 }
218 
219 /* Returns -1 on error, else 0. */
220 int
abandon_contract(ctid_t ctid)221 abandon_contract(ctid_t ctid)
222 {
223 	int fd;
224 	int err;
225 
226 	assert(ctid != -1);
227 
228 	if ((fd = open_contract_ctl_file(ctid)) == -1) {
229 		error_msg(gettext("Failed to abandon contract %d: %s"), ctid,
230 		    strerror(errno));
231 		return (-1);
232 	}
233 
234 	if ((err = ct_ctl_abandon(fd)) != 0) {
235 		(void) close(fd);
236 		error_msg(gettext("Failed to abandon contract %d: %s"), ctid,
237 		    strerror(err));
238 		return (-1);
239 	}
240 
241 	(void) close(fd);
242 
243 	return (0);
244 }
245