2 * Copyright (c) 2010-2014, Simon Schubert <2@0x2c.org>.
3 * Copyright (c) 2008 The DragonFly Project. All rights reserved.
5 * This code is derived from software contributed to The DragonFly Project
6 * by Simon Schubert <2@0x2c.org>.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * This binary is setuid root. Use extreme caution when touching
38 * user-supplied information. Keep the root window as small as possible.
42 #define USE_CAPSICUM 1
45 #include <sys/param.h>
47 #include <sys/capsicum.h>
51 #include <capsicum_helpers.h>
66 logfail(int exitcode, const char *fmt, ...)
75 vsnprintf(outs, sizeof(outs), fmt, ap);
81 syslog(LOG_ERR, errno ? "%s: %m" : "%s", outs);
83 syslog(LOG_ERR, errno ? "%m" : "unknown error");
89 * Create a mbox in /var/mail for a given user, or make sure
90 * the permissions are correct for dma.
94 main(int argc, char **argv)
107 * Open log fd now for capability sandbox.
109 openlog("dma-mbox-create", LOG_NDELAY, LOG_MAIL);
112 gr = getgrnam(DMA_GROUP);
114 logfail(EX_CONFIG, "cannot find dma group `%s'", DMA_GROUP);
116 mail_gid = gr->gr_gid;
118 if (setgid(mail_gid) != 0)
119 logfail(EX_NOPERM, "cannot set gid to %d (%s)", mail_gid, DMA_GROUP);
120 if (getegid() != mail_gid)
121 logfail(EX_NOPERM, "cannot set gid to %d (%s), still at %d", mail_gid, DMA_GROUP, getegid());
124 * We take exactly one argument: the username.
128 logfail(EX_USAGE, "no arguments");
132 syslog(LOG_NOTICE, "creating mbox for `%s'", user);
134 /* the username may not contain a pathname separator */
135 if (strchr(user, '/')) {
137 logfail(EX_DATAERR, "path separator in username `%s'", user);
141 /* verify the user exists */
145 logfail(EX_NOUSER, "cannot find user `%s'", user);
147 maildirfd = open(_PATH_MAILDIR, O_RDONLY);
149 logfail(EX_NOINPUT, "cannot open maildir %s", _PATH_MAILDIR);
152 * Cache NLS data, for strerror, for err(3), before entering capability
155 caph_cache_catpages();
158 * Cache local time before entering Capsicum capability sandbox.
163 cap_rights_init(&rights, CAP_CREATE, CAP_FCHMOD, CAP_FCHOWN,
164 CAP_LOOKUP, CAP_READ);
165 if (cap_rights_limit(maildirfd, &rights) < 0 && errno != ENOSYS)
166 err(EX_OSERR, "can't limit maildirfd rights");
168 /* Enter Capsicum capability sandbox */
169 if (cap_enter() < 0 && errno != ENOSYS)
170 err(EX_OSERR, "cap_enter");
173 user_uid = pw->pw_uid;
175 f = openat(maildirfd, user, O_RDONLY|O_CREAT|O_NOFOLLOW, 0600);
177 logfail(EX_NOINPUT, "cannot open mbox `%s'", user);
179 if (fchown(f, user_uid, mail_gid))
180 logfail(EX_OSERR, "cannot change owner of mbox `%s'", user);
183 logfail(EX_OSERR, "cannot change permissions of mbox `%s'",
186 /* file should be present with the right owner and permissions */
188 syslog(LOG_NOTICE, "successfully created mbox for `%s'", user);