1 /*- 2 * Copyright (c) 2016 Mariusz Zaborski <oshogbo@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 #ifndef _CAPSICUM_HELPERS_H_ 30 #define _CAPSICUM_HELPERS_H_ 31 32 #include <sys/param.h> 33 #include <sys/capsicum.h> 34 #include <sys/ioctl.h> 35 36 #include <errno.h> 37 #include <nl_types.h> 38 #include <termios.h> 39 #include <time.h> 40 #include <unistd.h> 41 42 #include <libcasper.h> 43 44 #define CAPH_IGNORE_EBADF 0x0001 45 #define CAPH_READ 0x0002 46 #define CAPH_WRITE 0x0004 47 #define CAPH_LOOKUP 0x0008 48 49 __BEGIN_DECLS 50 51 static const unsigned long caph_stream_cmds[] = 52 { 53 #ifdef TIOCGETA 54 TIOCGETA, 55 #endif 56 #ifdef TIOCGWINSZ 57 TIOCGWINSZ, 58 #endif 59 #ifdef FIODTYPE 60 FIODTYPE, 61 #endif 62 }; 63 static const uint32_t caph_stream_fcntls = CAP_FCNTL_GETFL; 64 65 static __inline void 66 caph_stream_rights(cap_rights_t *rights, int flags) 67 { 68 69 cap_rights_init(rights, CAP_EVENT, CAP_FCNTL, CAP_FSTAT, 70 CAP_IOCTL, CAP_SEEK); 71 72 if ((flags & CAPH_READ) != 0) 73 cap_rights_set(rights, CAP_READ); 74 if ((flags & CAPH_WRITE) != 0) 75 cap_rights_set(rights, CAP_WRITE); 76 if ((flags & CAPH_LOOKUP) != 0) 77 cap_rights_set(rights, CAP_LOOKUP); 78 } 79 80 static __inline int 81 caph_limit_stream(int fd, int flags) 82 { 83 cap_rights_t rights; 84 85 caph_stream_rights(&rights, flags); 86 if (cap_rights_limit(fd, &rights) < 0 && errno != ENOSYS) { 87 if (errno == EBADF && (flags & CAPH_IGNORE_EBADF) != 0) 88 return (0); 89 return (-1); 90 } 91 92 if (cap_ioctls_limit(fd, caph_stream_cmds, 93 nitems(caph_stream_cmds)) < 0 && errno != ENOSYS) 94 return (-1); 95 96 if (cap_fcntls_limit(fd, caph_stream_fcntls) < 0 && errno != ENOSYS) 97 return (-1); 98 99 return (0); 100 } 101 102 static __inline int 103 caph_limit_stdin(void) 104 { 105 106 return (caph_limit_stream(STDIN_FILENO, CAPH_READ)); 107 } 108 109 static __inline int 110 caph_limit_stderr(void) 111 { 112 113 return (caph_limit_stream(STDERR_FILENO, CAPH_WRITE)); 114 } 115 116 static __inline int 117 caph_limit_stdout(void) 118 { 119 120 return (caph_limit_stream(STDOUT_FILENO, CAPH_WRITE)); 121 } 122 123 static __inline int 124 caph_limit_stdio(void) 125 { 126 const int iebadf = CAPH_IGNORE_EBADF; 127 128 if (caph_limit_stream(STDIN_FILENO, CAPH_READ | iebadf) == -1 || 129 caph_limit_stream(STDOUT_FILENO, CAPH_WRITE | iebadf) == -1 || 130 caph_limit_stream(STDERR_FILENO, CAPH_WRITE | iebadf) == -1) 131 return (-1); 132 return (0); 133 } 134 135 static __inline void 136 caph_cache_tzdata(void) 137 { 138 139 tzset(); 140 } 141 142 static __inline void 143 caph_cache_catpages(void) 144 { 145 146 (void)catopen("libc", NL_CAT_LOCALE); 147 } 148 149 static __inline int 150 caph_enter(void) 151 { 152 153 if (cap_enter() < 0 && errno != ENOSYS) 154 return (-1); 155 156 return (0); 157 } 158 159 static __inline int 160 caph_rights_limit(int fd, const cap_rights_t *rights) 161 { 162 163 if (cap_rights_limit(fd, rights) < 0 && errno != ENOSYS) 164 return (-1); 165 166 return (0); 167 } 168 169 static __inline int 170 caph_ioctls_limit(int fd, const unsigned long *cmds, size_t ncmds) 171 { 172 173 if (cap_ioctls_limit(fd, cmds, ncmds) < 0 && errno != ENOSYS) 174 return (-1); 175 176 return (0); 177 } 178 179 static __inline int 180 caph_fcntls_limit(int fd, uint32_t fcntlrights) 181 { 182 183 if (cap_fcntls_limit(fd, fcntlrights) < 0 && errno != ENOSYS) 184 return (-1); 185 186 return (0); 187 } 188 189 static __inline int 190 caph_enter_casper(void) 191 { 192 193 return (CASPER_SUPPORT == 0 ? 0 : caph_enter()); 194 } 195 196 __END_DECLS 197 198 #endif /* _CAPSICUM_HELPERS_H_ */ 199