| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: class.c,v 1.4 1997/08/07 09:56:37 mdw Exp $ |
| 4 | * |
| 5 | * Handling classes of things nicely |
| 6 | * |
| 7 | * (c) 1997 EBI |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of `become' |
| 13 | * |
| 14 | * `Become' is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or |
| 17 | * (at your option) any later version. |
| 18 | * |
| 19 | * `Become' is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with `become'; if not, write to the Free Software Foundation, |
| 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 27 | */ |
| 28 | |
| 29 | /*----- Revision history --------------------------------------------------* |
| 30 | * |
| 31 | * $Log: class.c,v $ |
| 32 | * Revision 1.4 1997/08/07 09:56:37 mdw |
| 33 | * (Log entry for previous version is bogus.) Minor changes to host |
| 34 | * checking code. |
| 35 | * |
| 36 | * Revision 1.2 1997/08/04 10:24:21 mdw |
| 37 | * Sources placed under CVS control. |
| 38 | * |
| 39 | * Revision 1.1 1997/07/21 13:47:52 mdw |
| 40 | * Initial revision |
| 41 | * |
| 42 | */ |
| 43 | |
| 44 | /*----- Header files ------------------------------------------------------*/ |
| 45 | |
| 46 | /* --- ANSI headers --- */ |
| 47 | |
| 48 | #include <stdio.h> |
| 49 | #include <stdlib.h> |
| 50 | #include <string.h> |
| 51 | |
| 52 | /* --- Unix headers --- */ |
| 53 | |
| 54 | #include <sys/types.h> |
| 55 | #include <sys/socket.h> |
| 56 | |
| 57 | #include <netinet/in.h> |
| 58 | |
| 59 | #include <arpa/inet.h> |
| 60 | |
| 61 | #include <netdb.h> |
| 62 | |
| 63 | /* --- Local headers --- */ |
| 64 | |
| 65 | #include "become.h" |
| 66 | #include "class.h" |
| 67 | #include "set.h" |
| 68 | #include "sym.h" |
| 69 | #include "utils.h" |
| 70 | |
| 71 | /*----- Global variables --------------------------------------------------*/ |
| 72 | |
| 73 | static classdef class__all = { clType_all, -1, 0 }; |
| 74 | classdef *class_all = &class__all; |
| 75 | |
| 76 | /*----- Wildcard matching -------------------------------------------------*/ |
| 77 | |
| 78 | /* --- @class__wildMatch@ --- * |
| 79 | * |
| 80 | * Arguments: @const char *pat@ = pointer to pattern string |
| 81 | * @const char *p@ = pointer to target string |
| 82 | * |
| 83 | * Returns: Zero if no match, nonzero if match. |
| 84 | * |
| 85 | * Use: Wildcard-matches the pattern against the target string. |
| 86 | */ |
| 87 | |
| 88 | static int class__wildMatch(const char *pat, const char *p) |
| 89 | { |
| 90 | for (;;) { |
| 91 | if (*pat == 0 && *p == 0) |
| 92 | return (42); /* For sadism's sake */ |
| 93 | else if (*pat == '*') { |
| 94 | while (*pat == '*') |
| 95 | pat++; |
| 96 | do { |
| 97 | if (class__wildMatch(pat, p)) |
| 98 | return (27); /* Nyahaha */ |
| 99 | p++; |
| 100 | } while (*p); |
| 101 | return (0); |
| 102 | } else if (*pat == '?' || *pat == *p) |
| 103 | p++, pat++; |
| 104 | else |
| 105 | return (0); |
| 106 | } |
| 107 | } |
| 108 | |
| 109 | /*----- Main code ---------------------------------------------------------*/ |
| 110 | |
| 111 | /* --- @class_create@ --- * |
| 112 | * |
| 113 | * Arguments: @unsigned type@ = type of the class to create |
| 114 | * @sym_table *t@ = pointer to symbol table which stores info |
| 115 | * |
| 116 | * Returns: Pointer to a @classdef@ which maintains the class's info. |
| 117 | * |
| 118 | * Use: Creates a new class definition. The new definition has one |
| 119 | * reference attached to it (which is the one you get returned). |
| 120 | */ |
| 121 | |
| 122 | classdef *class_create(unsigned type, sym_table *t) |
| 123 | { |
| 124 | classdef *c = xmalloc(sizeof(*c)); |
| 125 | c->type = type; |
| 126 | c->ref = 1; |
| 127 | c->t = t; |
| 128 | return (c); |
| 129 | } |
| 130 | |
| 131 | /* --- @class_inc@ --- * |
| 132 | * |
| 133 | * Arguments: @classdef *c@ = pointer to a class block |
| 134 | * |
| 135 | * Returns: --- |
| 136 | * |
| 137 | * Use: Adds a reference to the class definition. |
| 138 | */ |
| 139 | |
| 140 | void class_inc(classdef *c) |
| 141 | { |
| 142 | if (c != class_all) |
| 143 | c->ref++; |
| 144 | } |
| 145 | |
| 146 | /* --- @class_dec@ --- * |
| 147 | * |
| 148 | * Arguments: @classdef *c@ = pointer to a class block |
| 149 | * |
| 150 | * Returns: --- |
| 151 | * |
| 152 | * Use: Removes a reference to a class block. |
| 153 | */ |
| 154 | |
| 155 | void class_dec(classdef *c) |
| 156 | { |
| 157 | if (c != class_all && !--c->ref) { |
| 158 | sym_destroyTable(c->t); |
| 159 | free(c); |
| 160 | } |
| 161 | } |
| 162 | |
| 163 | /* --- @class_userMatch@ --- * |
| 164 | * |
| 165 | * Arguments: @classdef *c@ = pointer to a class block |
| 166 | * @int u@ = uid number to check against |
| 167 | * |
| 168 | * Returns: Zero if no match, nonzero if it matched. |
| 169 | * |
| 170 | * Use: Looks to see if a user is in a group. |
| 171 | */ |
| 172 | |
| 173 | int class_userMatch(classdef *c, int u) |
| 174 | { |
| 175 | if (~c->type & clType_user) |
| 176 | return (0); |
| 177 | else if (c == class_all) { |
| 178 | T( trace(TRACE_CHECK, "check: user %i matched by all", u); ) |
| 179 | return (1); |
| 180 | } else { |
| 181 | sym_base *s = sym_find(c->t, (char *)&u, sizeof(u), 0, 0); |
| 182 | T( trace(TRACE_CHECK, |
| 183 | s ? "check: user %i matched" : "check: user %i not matched", |
| 184 | u); ) |
| 185 | return (s != 0); |
| 186 | } |
| 187 | } |
| 188 | |
| 189 | /* --- @class_commandMatch@ --- * |
| 190 | * |
| 191 | * Arguments: @classdef *c@ = pointer to a class block |
| 192 | * @const char *p@ = pointer to command string to match |
| 193 | * |
| 194 | * Returns: Zero for no match, nonzero if it matched. |
| 195 | * |
| 196 | * Use: Tries to match a string against the wildcard patterns in the |
| 197 | * given class. Note that this involves examining all the |
| 198 | * items, so it's not too quick. Then again, you don't have |
| 199 | * big command classes, do you...? |
| 200 | */ |
| 201 | |
| 202 | int class_commandMatch(classdef *c, const char *p) |
| 203 | { |
| 204 | sym_iter i; |
| 205 | sym_base *s; |
| 206 | |
| 207 | if (~c->type & clType_command) |
| 208 | return (0); |
| 209 | else if (c == class_all) { |
| 210 | T( trace(TRACE_CHECK, "check: command `%s' matched by all", p); ) |
| 211 | return (1); |
| 212 | } else { |
| 213 | for (sym_createIter(&i, c->t); (s = sym_next(&i)) != 0; ) { |
| 214 | if (class__wildMatch(s->name, p)) { |
| 215 | T( trace(TRACE_CHECK, "check: command `%s' matched by `%s'", |
| 216 | p, s->name); ) |
| 217 | return (1); |
| 218 | } |
| 219 | } |
| 220 | T( trace(TRACE_CHECK, "check: command `%s' not matched", p); ) |
| 221 | return (0); |
| 222 | } |
| 223 | } |
| 224 | |
| 225 | /* --- @class_hostMatch@ --- * |
| 226 | * |
| 227 | * Arguments: @classdef *c@ = pointer to class block |
| 228 | * @struct in_addr addr@ = IP address to match |
| 229 | * |
| 230 | * Returns: Zero for no match, nonzero if it matched. |
| 231 | * |
| 232 | * Use: Tries to match an IP address against the patterns and masks |
| 233 | * in the given class. |
| 234 | */ |
| 235 | |
| 236 | int class_hostMatch(classdef *c, struct in_addr addr) |
| 237 | { |
| 238 | sym_iter i; |
| 239 | sym_base *s; |
| 240 | const char *a; |
| 241 | struct hostent *he; |
| 242 | char **p; |
| 243 | |
| 244 | if (~c->type & clType_host) |
| 245 | return (0); |
| 246 | else if (c == class_all) { |
| 247 | T( trace(TRACE_CHECK, "check: host %s matched by all", |
| 248 | inet_ntoa(addr)); ) |
| 249 | return (1); |
| 250 | } else { |
| 251 | |
| 252 | /* --- Get the dotted-quad and other names for the address --- */ |
| 253 | |
| 254 | if ((a = inet_ntoa(addr)) == 0) { |
| 255 | T( trace(TRACE_CHECK, "check: couldn't translate address (erk!)"); ) |
| 256 | return (0); |
| 257 | } |
| 258 | |
| 259 | if ((he = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == 0) |
| 260 | T( trace(TRACE_CHECK, "check: couldn't resolve hostname for %s", a); ) |
| 261 | |
| 262 | /* --- Now search the list for a match --- * |
| 263 | * |
| 264 | * This is almost infinitely slow, I'm afraid. |
| 265 | */ |
| 266 | |
| 267 | for (sym_createIter(&i, c->t); (s = sym_next(&i)) != 0; ) { |
| 268 | |
| 269 | /* --- Check the dotted-quad name first --- */ |
| 270 | |
| 271 | if (class__wildMatch(s->name, a)) { |
| 272 | T( trace(TRACE_CHECK, "check: host address `%s' matched by `%s'", |
| 273 | a, s->name); ) |
| 274 | return (1); |
| 275 | } |
| 276 | |
| 277 | if (he) { |
| 278 | |
| 279 | /* --- Now try the host's main name --- */ |
| 280 | |
| 281 | if (class__wildMatch(s->name, he->h_name)) { |
| 282 | T( trace(TRACE_CHECK, "check: host name `%s' matched by `%s'", |
| 283 | he->h_name, s->name); ) |
| 284 | return (1); |
| 285 | } |
| 286 | |
| 287 | /* --- Now go through all the names --- */ |
| 288 | |
| 289 | for (p = he->h_aliases; *p; p++) { |
| 290 | if (class__wildMatch(s->name, *p)) { |
| 291 | T( trace(TRACE_CHECK, "check: host alias `%s' matched by `%s'", |
| 292 | *p, s->name); ) |
| 293 | return (1); |
| 294 | } |
| 295 | } |
| 296 | } |
| 297 | } |
| 298 | |
| 299 | T( trace(TRACE_CHECK, "check: couldn't match hostname `%s'", |
| 300 | he->h_name); ) |
| 301 | return (0); |
| 302 | } |
| 303 | } |
| 304 | |
| 305 | /* --- @class_dump@ --- * |
| 306 | * |
| 307 | * Arguments: @classdef *c@ = pointer to a class block |
| 308 | * |
| 309 | * Returns: --- |
| 310 | * |
| 311 | * Use: Dumps the contents of a class to a stream. |
| 312 | */ |
| 313 | |
| 314 | void class_dump(classdef *c) |
| 315 | { |
| 316 | sym_iter i; |
| 317 | sym_base *s; |
| 318 | |
| 319 | /* --- Dump the table --- */ |
| 320 | |
| 321 | if (c->type != clType_all) { |
| 322 | for (sym_createIter(&i, c->t); (s = sym_next(&i)) != 0; ) { |
| 323 | switch (c->type) { |
| 324 | case clType_user: |
| 325 | trace(TRACE_RULE, " %i", *(int *)s->name); |
| 326 | break; |
| 327 | case clType_command: |
| 328 | case clType_host: |
| 329 | trace(TRACE_RULE, " `%s'", s->name); |
| 330 | break; |
| 331 | } |
| 332 | } |
| 333 | } |
| 334 | else |
| 335 | trace(TRACE_RULE, " ALL"); |
| 336 | } |
| 337 | |
| 338 | /*----- That's all, folks -------------------------------------------------*/ |