1 /* Authors: Joshua Brindle <jbrindle (at) tresys.com> 2 * Jason Tang <jtang (at) tresys.com> 3 * 4 * Copyright (C) 2005-2006 Tresys Technology, LLC 5 * 6 * This library is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Lesser General Public 8 * License as published by the Free Software Foundation; either 9 * version 2.1 of the License, or (at your option) any later version. 10 * 11 * This library is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Lesser General Public License for more details. 15 * 16 * You should have received a copy of the GNU Lesser General Public 17 * License along with this library; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21 #include <assert.h> 22 #include <ctype.h> 23 #include <stdarg.h> 24 #include <stdio.h> 25 #include <stdlib.h> 26 27 #include <sepol/policydb/flask_types.h> 28 #include <sepol/policydb/policydb.h> 29 #include <sepol/policydb/util.h> 30 #include <dso.h> 31 32 struct val_to_name { 33 unsigned int val; 34 char *name; 35 }; 36 37 /* Add an unsigned integer to a dynamically reallocated array. *cnt 38 * is a reference pointer to the number of values already within array 39 * *a; it will be incremented upon successfully appending i. If *a is 40 * NULL then this function will create a new array (*cnt is reset to 41 * 0). Return 0 on success, -1 on out of memory. */ 42 int add_i_to_a(uint32_t i, uint32_t * cnt, uint32_t ** a) 43 { 44 if (cnt == NULL || a == NULL) 45 return -1; 46 47 /* FIX ME: This is not very elegant! We use an array that we 48 * grow as new uint32_t are added to an array. But rather 49 * than be smart about it, for now we realloc() the array each 50 * time a new uint32_t is added! */ 51 if (*a != NULL) 52 *a = (uint32_t *) realloc(*a, (*cnt + 1) * sizeof(uint32_t)); 53 else { /* empty list */ 54 55 *cnt = 0; 56 *a = (uint32_t *) malloc(sizeof(uint32_t)); 57 } 58 if (*a == NULL) { 59 return -1; 60 } 61 (*a)[*cnt] = i; 62 (*cnt)++; 63 return 0; 64 } 65 66 static int perm_name(hashtab_key_t key, hashtab_datum_t datum, void *data) 67 { 68 struct val_to_name *v = data; 69 perm_datum_t *perdatum; 70 71 perdatum = (perm_datum_t *) datum; 72 73 if (v->val == perdatum->s.value) { 74 v->name = key; 75 return 1; 76 } 77 78 return 0; 79 } 80 81 char *sepol_av_to_string(policydb_t * policydbp, uint32_t tclass, 82 sepol_access_vector_t av) 83 { 84 struct val_to_name v; 85 static char avbuf[1024]; 86 class_datum_t *cladatum; 87 char *perm = NULL, *p; 88 unsigned int i; 89 int rc; 90 int avlen = 0, len; 91 92 cladatum = policydbp->class_val_to_struct[tclass - 1]; 93 p = avbuf; 94 for (i = 0; i < cladatum->permissions.nprim; i++) { 95 if (av & (1 << i)) { 96 v.val = i + 1; 97 rc = hashtab_map(cladatum->permissions.table, 98 perm_name, &v); 99 if (!rc && cladatum->comdatum) { 100 rc = hashtab_map(cladatum->comdatum-> 101 permissions.table, perm_name, 102 &v); 103 } 104 if (rc) 105 perm = v.name; 106 if (perm) { 107 len = 108 snprintf(p, sizeof(avbuf) - avlen, " %s", 109 perm); 110 if (len < 0 111 || (size_t) len >= (sizeof(avbuf) - avlen)) 112 return NULL; 113 p += len; 114 avlen += len; 115 } 116 } 117 } 118 119 return avbuf; 120 } 121 122 #define next_bit_in_range(i, p) ((i + 1 < sizeof(p)*8) && xperm_test((i + 1), p)) 123 124 char *sepol_extended_perms_to_string(avtab_extended_perms_t *xperms) 125 { 126 uint16_t value; 127 uint16_t low_bit; 128 uint16_t low_value; 129 unsigned int bit; 130 unsigned int in_range = 0; 131 static char xpermsbuf[2048]; 132 xpermsbuf[0] = '\0'; 133 char *p; 134 int len, xpermslen = 0; 135 p = xpermsbuf; 136 137 if ((xperms->specified != AVTAB_XPERMS_IOCTLFUNCTION) 138 && (xperms->specified != AVTAB_XPERMS_IOCTLDRIVER)) 139 return NULL; 140 141 len = snprintf(p, sizeof(xpermsbuf) - xpermslen, "ioctl { "); 142 p += len; 143 xpermslen += len; 144 145 for (bit = 0; bit < sizeof(xperms->perms)*8; bit++) { 146 if (!xperm_test(bit, xperms->perms)) 147 continue; 148 149 if (in_range && next_bit_in_range(bit, xperms->perms)) { 150 /* continue until high value found */ 151 continue; 152 } else if (next_bit_in_range(bit, xperms->perms)) { 153 /* low value */ 154 low_bit = bit; 155 in_range = 1; 156 continue; 157 } 158 159 if (xperms->specified & AVTAB_XPERMS_IOCTLFUNCTION) { 160 value = xperms->driver<<8 | bit; 161 low_value = xperms->driver<<8 | low_bit; 162 if (in_range) { 163 len = snprintf(p, sizeof(xpermsbuf) - xpermslen, "0x%hx-0x%hx ", low_value, value); 164 } else { 165 len = snprintf(p, sizeof(xpermsbuf) - xpermslen, "0x%hx ", value); 166 } 167 } else if (xperms->specified & AVTAB_XPERMS_IOCTLDRIVER) { 168 value = bit << 8; 169 low_value = low_bit << 8; 170 if (in_range) { 171 len = snprintf(p, sizeof(xpermsbuf) - xpermslen, "0x%hx-0x%hx ", low_value, (uint16_t) (value|0xff)); 172 } else { 173 len = snprintf(p, sizeof(xpermsbuf) - xpermslen, "0x%hx-0x%hx ", value, (uint16_t) (value|0xff)); 174 } 175 176 } 177 178 if (len < 0 || (size_t) len >= (sizeof(xpermsbuf) - xpermslen)) 179 return NULL; 180 181 p += len; 182 xpermslen += len; 183 if (in_range) 184 in_range = 0; 185 } 186 187 len = snprintf(p, sizeof(xpermsbuf) - xpermslen, "}"); 188 if (len < 0 || (size_t) len >= (sizeof(xpermsbuf) - xpermslen)) 189 return NULL; 190 191 return xpermsbuf; 192 } 193 194 /* 195 * The tokenize and tokenize_str functions may be used to 196 * replace sscanf to read tokens from buffers. 197 */ 198 199 /* Read a token from a buffer */ 200 static inline int tokenize_str(char delim, char **str, char **ptr, size_t *len) 201 { 202 char *tmp_buf = *ptr; 203 *str = NULL; 204 205 while (**ptr != '\0') { 206 if (isspace(delim) && isspace(**ptr)) { 207 (*ptr)++; 208 break; 209 } else if (!isspace(delim) && **ptr == delim) { 210 (*ptr)++; 211 break; 212 } 213 214 (*ptr)++; 215 } 216 217 *len = *ptr - tmp_buf; 218 /* If the end of the string has not been reached, this will ensure the 219 * delimiter is not included when returning the token. 220 */ 221 if (**ptr != '\0') { 222 (*len)--; 223 } 224 225 *str = strndup(tmp_buf, *len); 226 if (!*str) { 227 return -1; 228 } 229 230 /* Squash spaces if the delimiter is a whitespace character */ 231 while (**ptr != '\0' && isspace(delim) && isspace(**ptr)) { 232 (*ptr)++; 233 } 234 235 return 0; 236 } 237 238 /* 239 * line_buf - Buffer containing string to tokenize. 240 * delim - The delimiter used to tokenize line_buf. A whitespace delimiter will 241 * be tokenized using isspace(). 242 * num_args - The number of parameter entries to process. 243 * ... - A 'char **' for each parameter. 244 * returns - The number of items processed. 245 * 246 * This function calls tokenize_str() to do the actual string processing. The 247 * caller is responsible for calling free() on each additional argument. The 248 * function will not tokenize more than num_args and the last argument will 249 * contain the remaining content of line_buf. If the delimiter is any whitespace 250 * character, then all whitespace will be squashed. 251 */ 252 int hidden tokenize(char *line_buf, char delim, int num_args, ...) 253 { 254 char **arg, *buf_p; 255 int rc, items; 256 size_t arg_len = 0; 257 va_list ap; 258 259 buf_p = line_buf; 260 261 /* Process the arguments */ 262 va_start(ap, num_args); 263 264 for (items = 0; items < num_args && *buf_p != '\0'; items++) { 265 arg = va_arg(ap, char **); 266 267 /* Save the remainder of the string in arg */ 268 if (items == num_args - 1) { 269 *arg = strdup(buf_p); 270 if (*arg == NULL) { 271 goto exit; 272 } 273 274 continue; 275 } 276 277 rc = tokenize_str(delim, arg, &buf_p, &arg_len); 278 if (rc < 0) { 279 goto exit; 280 } 281 } 282 283 exit: 284 va_end(ap); 285 return items; 286 } 287
