1 /*- 2 * Copyright (c) 2010 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Pawel Jakub Dawidek under sponsorship from 6 * the FreeBSD Foundation. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/types.h> 34 #include <sys/disk.h> 35 #include <sys/ioctl.h> 36 #include <sys/stat.h> 37 38 #include <errno.h> 39 #include <fcntl.h> 40 #include <pwd.h> 41 #include <unistd.h> 42 43 #include <pjdlog.h> 44 45 #include "hast.h" 46 #include "subr.h" 47 48 int 49 provinfo(struct hast_resource *res, bool dowrite) 50 { 51 struct stat sb; 52 53 PJDLOG_ASSERT(res->hr_localpath != NULL && 54 res->hr_localpath[0] != '\0'); 55 56 if (res->hr_localfd == -1) { 57 res->hr_localfd = open(res->hr_localpath, 58 dowrite ? O_RDWR : O_RDONLY); 59 if (res->hr_localfd < 0) { 60 KEEP_ERRNO(pjdlog_errno(LOG_ERR, "Unable to open %s", 61 res->hr_localpath)); 62 return (-1); 63 } 64 } 65 if (fstat(res->hr_localfd, &sb) < 0) { 66 KEEP_ERRNO(pjdlog_errno(LOG_ERR, "Unable to stat %s", 67 res->hr_localpath)); 68 return (-1); 69 } 70 if (S_ISCHR(sb.st_mode)) { 71 /* 72 * If this is character device, it is most likely GEOM provider. 73 */ 74 if (ioctl(res->hr_localfd, DIOCGMEDIASIZE, 75 &res->hr_local_mediasize) < 0) { 76 KEEP_ERRNO(pjdlog_errno(LOG_ERR, 77 "Unable obtain provider %s mediasize", 78 res->hr_localpath)); 79 return (-1); 80 } 81 if (ioctl(res->hr_localfd, DIOCGSECTORSIZE, 82 &res->hr_local_sectorsize) < 0) { 83 KEEP_ERRNO(pjdlog_errno(LOG_ERR, 84 "Unable obtain provider %s sectorsize", 85 res->hr_localpath)); 86 return (-1); 87 } 88 } else if (S_ISREG(sb.st_mode)) { 89 /* 90 * We also support regular files for which we hardcode 91 * sector size of 512 bytes. 92 */ 93 res->hr_local_mediasize = sb.st_size; 94 res->hr_local_sectorsize = 512; 95 } else { 96 /* 97 * We support no other file types. 98 */ 99 pjdlog_error("%s is neither GEOM provider nor regular file.", 100 res->hr_localpath); 101 errno = EFTYPE; 102 return (-1); 103 } 104 return (0); 105 } 106 107 const char * 108 role2str(int role) 109 { 110 111 switch (role) { 112 case HAST_ROLE_INIT: 113 return ("init"); 114 case HAST_ROLE_PRIMARY: 115 return ("primary"); 116 case HAST_ROLE_SECONDARY: 117 return ("secondary"); 118 } 119 return ("unknown"); 120 } 121 122 int 123 drop_privs(void) 124 { 125 struct passwd *pw; 126 uid_t ruid, euid, suid; 127 gid_t rgid, egid, sgid; 128 gid_t gidset[1]; 129 130 /* 131 * According to getpwnam(3) we have to clear errno before calling the 132 * function to be able to distinguish between an error and missing 133 * entry (with is not treated as error by getpwnam(3)). 134 */ 135 errno = 0; 136 pw = getpwnam(HAST_USER); 137 if (pw == NULL) { 138 if (errno != 0) { 139 KEEP_ERRNO(pjdlog_errno(LOG_ERR, 140 "Unable to find info about '%s' user", HAST_USER)); 141 return (-1); 142 } else { 143 pjdlog_error("'%s' user doesn't exist.", HAST_USER); 144 errno = ENOENT; 145 return (-1); 146 } 147 } 148 if (chroot(pw->pw_dir) == -1) { 149 KEEP_ERRNO(pjdlog_errno(LOG_ERR, 150 "Unable to change root directory to %s", pw->pw_dir)); 151 return (-1); 152 } 153 PJDLOG_VERIFY(chdir("/") == 0); 154 gidset[0] = pw->pw_gid; 155 if (setgroups(1, gidset) == -1) { 156 KEEP_ERRNO(pjdlog_errno(LOG_ERR, 157 "Unable to set groups to gid %u", 158 (unsigned int)pw->pw_gid)); 159 return (-1); 160 } 161 if (setgid(pw->pw_gid) == -1) { 162 KEEP_ERRNO(pjdlog_errno(LOG_ERR, "Unable to set gid to %u", 163 (unsigned int)pw->pw_gid)); 164 return (-1); 165 } 166 if (setuid(pw->pw_uid) == -1) { 167 KEEP_ERRNO(pjdlog_errno(LOG_ERR, "Unable to set uid to %u", 168 (unsigned int)pw->pw_uid)); 169 return (-1); 170 } 171 172 /* 173 * Better be sure that everything succeeded. 174 */ 175 PJDLOG_VERIFY(getresuid(&ruid, &euid, &suid) == 0); 176 PJDLOG_VERIFY(ruid == pw->pw_uid); 177 PJDLOG_VERIFY(euid == pw->pw_uid); 178 PJDLOG_VERIFY(suid == pw->pw_uid); 179 PJDLOG_VERIFY(getresgid(&rgid, &egid, &sgid) == 0); 180 PJDLOG_VERIFY(rgid == pw->pw_gid); 181 PJDLOG_VERIFY(egid == pw->pw_gid); 182 PJDLOG_VERIFY(sgid == pw->pw_gid); 183 PJDLOG_VERIFY(getgroups(0, NULL) == 1); 184 PJDLOG_VERIFY(getgroups(1, gidset) == 1); 185 PJDLOG_VERIFY(gidset[0] == pw->pw_gid); 186 187 return (0); 188 } 189