#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static int debug; static int warn; void usage(char *arg0) { fprintf(stderr, "%s [-w|--warn] [-z|--debug] [-e|--equiv] [-d|--diff] [-D|--dups] [-p|--permissive] [-n|--neverallow ] -P \n", arg0); exit(1); } int load_policy(char *filename, policydb_t * policydb, struct policy_file *pf) { int fd; struct stat sb; void *map; int ret; fd = open(filename, O_RDONLY); if (fd < 0) { fprintf(stderr, "Can't open '%s': %s\n", filename, strerror(errno)); return 1; } if (fstat(fd, &sb) < 0) { fprintf(stderr, "Can't stat '%s': %s\n", filename, strerror(errno)); close(fd); return 1; } map = mmap(NULL, sb.st_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); if (map == MAP_FAILED) { fprintf(stderr, "Can't mmap '%s': %s\n", filename, strerror(errno)); close(fd); return 1; } policy_file_init(pf); pf->type = PF_USE_MEMORY; pf->data = map; pf->len = sb.st_size; if (policydb_init(policydb)) { fprintf(stderr, "Could not initialize policydb!\n"); close(fd); munmap(map, sb.st_size); return 1; } ret = policydb_read(policydb, pf, 0); if (ret) { fprintf(stderr, "error(s) encountered while parsing configuration\n"); close(fd); munmap(map, sb.st_size); return 1; } return 0; } static int insert_type_rule(avtab_key_t * k, avtab_datum_t * d, struct avtab_node *type_rules) { struct avtab_node *p, *c, *n; for (p = type_rules, c = type_rules->next; c; p = c, c = c->next) { /* * Find the insertion point, keeping the list * ordered by source type, then target type, then * target class. */ if (k->source_type < c->key.source_type) break; if (k->source_type == c->key.source_type && k->target_type < c->key.target_type) break; if (k->source_type == c->key.source_type && k->target_type == c->key.target_type && k->target_class <= c->key.target_class) break; } if (c && k->source_type == c->key.source_type && k->target_type == c->key.target_type && k->target_class == c->key.target_class) { c->datum.data |= d->data; return 0; } /* Insert the rule */ n = malloc(sizeof(struct avtab_node)); if (!n) { fprintf(stderr, "out of memory\n"); exit(1); } n->key = *k; n->datum = *d; n->next = p->next; p->next = n; return 0; } static int create_type_rules_helper(avtab_key_t * k, avtab_datum_t * d, void *args) { struct avtab_node *type_rules = args; avtab_key_t key; /* * Insert the rule into the list for * the source type. The source type value * is cleared as we want to compare against other type * rules with different source types. */ key = *k; key.source_type = 0; if (k->source_type == k->target_type) { /* Clear target type as well; this is a self rule. */ key.target_type = 0; } if (insert_type_rule(&key, d, &type_rules[k->source_type - 1])) return -1; if (k->source_type == k->target_type) return 0; /* * If the target type differs, then we also * insert the rule into the list for the target * type. We clear the target type value so that * we can compare against other type rules with * different target types. */ key = *k; key.target_type = 0; if (insert_type_rule(&key, d, &type_rules[k->target_type - 1])) return -1; return 0; } static int create_type_rules(avtab_key_t * k, avtab_datum_t * d, void *args) { if (k->specified & AVTAB_ALLOWED) return create_type_rules_helper(k, d, args); return 0; } static int create_type_rules_cond(avtab_key_t * k, avtab_datum_t * d, void *args) { if ((k->specified & (AVTAB_ALLOWED|AVTAB_ENABLED)) == (AVTAB_ALLOWED|AVTAB_ENABLED)) return create_type_rules_helper(k, d, args); return 0; } static void free_type_rules(struct avtab_node *l) { struct avtab_node *tmp; while (l) { tmp = l; l = l->next; free(tmp); } } static void display_allow(policydb_t *policydb, avtab_key_t *key, int idx, uint32_t perms) { printf(" allow %s %s:%s { %s };\n", policydb->p_type_val_to_name[key->source_type ? key->source_type - 1 : idx], key->target_type == key->source_type ? "self" : policydb->p_type_val_to_name[key->target_type ? key->target_type - 1 : idx], policydb->p_class_val_to_name[key->target_class - 1], sepol_av_to_string (policydb, key->target_class, perms)); } static int find_match(policydb_t *policydb, struct avtab_node *l1, int idx1, struct avtab_node *l2, int idx2) { struct avtab_node *c; uint32_t perms1, perms2; for (c = l2; c; c = c->next) { if (l1->key.source_type < c->key.source_type) break; if (l1->key.source_type == c->key.source_type && l1->key.target_type < c->key.target_type) break; if (l1->key.source_type == c->key.source_type && l1->key.target_type == c->key.target_type && l1->key.target_class <= c->key.target_class) break; } if (c && l1->key.source_type == c->key.source_type && l1->key.target_type == c->key.target_type && l1->key.target_class == c->key.target_class) { perms1 = l1->datum.data & ~c->datum.data; perms2 = c->datum.data & ~l1->datum.data; if (perms1 || perms2) { if (perms1) display_allow(policydb, &l1->key, idx1, perms1); if (perms2) display_allow(policydb, &c->key, idx2, perms2); printf("\n"); return 1; } } return 0; } static int analyze_types(policydb_t * policydb, char equiv, char diff) { avtab_t exp_avtab, exp_cond_avtab; struct avtab_node *type_rules, *l1, *l2; struct type_datum *type; size_t i, j; /* * Create a list of access vector rules for each type * from the access vector table. */ type_rules = malloc(sizeof(struct avtab_node) * policydb->p_types.nprim); if (!type_rules) { fprintf(stderr, "out of memory\n"); exit(1); } memset(type_rules, 0, sizeof(struct avtab_node) * policydb->p_types.nprim); if (avtab_init(&exp_avtab) || avtab_init(&exp_cond_avtab)) { fputs("out of memory\n", stderr); return -1; } if (expand_avtab(policydb, &policydb->te_avtab, &exp_avtab)) { fputs("out of memory\n", stderr); avtab_destroy(&exp_avtab); return -1; } if (expand_avtab(policydb, &policydb->te_cond_avtab, &exp_cond_avtab)) { fputs("out of memory\n", stderr); avtab_destroy(&exp_avtab); return -1; } if (avtab_map(&exp_avtab, create_type_rules, type_rules)) exit(1); if (avtab_map(&exp_cond_avtab, create_type_rules_cond, type_rules)) exit(1); avtab_destroy(&exp_avtab); avtab_destroy(&exp_cond_avtab); /* * Compare the type lists and identify similar types. */ for (i = 0; i < policydb->p_types.nprim - 1; i++) { if (!type_rules[i].next) continue; type = policydb->type_val_to_struct[i]; if (type->flavor) { free_type_rules(type_rules[i].next); type_rules[i].next = NULL; continue; } for (j = i + 1; j < policydb->p_types.nprim; j++) { type = policydb->type_val_to_struct[j]; if (type->flavor) { free_type_rules(type_rules[j].next); type_rules[j].next = NULL; continue; } for (l1 = type_rules[i].next, l2 = type_rules[j].next; l1 && l2; l1 = l1->next, l2 = l2->next) { if (l1->key.source_type != l2->key.source_type) break; if (l1->key.target_type != l2->key.target_type) break; if (l1->key.target_class != l2->key.target_class || l1->datum.data != l2->datum.data) break; } if (l1 || l2) { if (diff) { printf ("Types %s and %s differ, starting with:\n", policydb->p_type_val_to_name[i], policydb->p_type_val_to_name[j]); if (l1 && l2) { if (find_match(policydb, l1, i, l2, j)) continue; if (find_match(policydb, l2, j, l1, i)) continue; } if (l1) display_allow(policydb, &l1->key, i, l1->datum.data); if (l2) display_allow(policydb, &l2->key, j, l2->datum.data); printf("\n"); } continue; } free_type_rules(type_rules[j].next); type_rules[j].next = NULL; if (equiv) { printf("Types %s and %s are equivalent.\n", policydb->p_type_val_to_name[i], policydb->p_type_val_to_name[j]); } } free_type_rules(type_rules[i].next); type_rules[i].next = NULL; } free(type_rules); return 0; } static int find_dups_helper(avtab_key_t * k, avtab_datum_t * d, void *args) { policydb_t *policydb = args; ebitmap_t *sattr, *tattr; ebitmap_node_t *snode, *tnode; unsigned int i, j; avtab_key_t avkey; avtab_ptr_t node; struct type_datum *stype, *ttype, *stype2, *ttype2; bool attrib1, attrib2; if (!(k->specified & AVTAB_ALLOWED)) return 0; if (k->source_type == k->target_type) return 0; /* self rule */ avkey.target_class = k->target_class; avkey.specified = k->specified; sattr = &policydb->type_attr_map[k->source_type - 1]; tattr = &policydb->type_attr_map[k->target_type - 1]; stype = policydb->type_val_to_struct[k->source_type - 1]; ttype = policydb->type_val_to_struct[k->target_type - 1]; attrib1 = stype->flavor || ttype->flavor; ebitmap_for_each_bit(sattr, snode, i) { if (!ebitmap_node_get_bit(snode, i)) continue; ebitmap_for_each_bit(tattr, tnode, j) { if (!ebitmap_node_get_bit(tnode, j)) continue; avkey.source_type = i + 1; avkey.target_type = j + 1; if (avkey.source_type == k->source_type && avkey.target_type == k->target_type) continue; if (avkey.source_type == avkey.target_type) continue; /* self rule */ stype2 = policydb->type_val_to_struct[avkey.source_type - 1]; ttype2 = policydb->type_val_to_struct[avkey.target_type - 1]; attrib2 = stype2->flavor || ttype2->flavor; if (attrib1 && attrib2) continue; /* overlapping attribute-based rules */ for (node = avtab_search_node(&policydb->te_avtab, &avkey); node != NULL; node = avtab_search_node_next(node, avkey.specified)) { uint32_t perms = node->datum.data & d->data; if ((attrib1 && perms == node->datum.data) || (attrib2 && perms == d->data)) { /* * The attribute-based rule is a superset of the * non-attribute-based rule. This is a dup. */ printf("Duplicate allow rule found:\n"); display_allow(policydb, k, i, d->data); display_allow(policydb, &node->key, i, node->datum.data); printf("\n"); } } } } return 0; } static int find_dups(policydb_t * policydb) { if (avtab_map(&policydb->te_avtab, find_dups_helper, policydb)) return -1; return 0; } static int list_permissive(policydb_t * policydb) { struct ebitmap_node *n; unsigned int bit; /* * iterate over all domains and check if domain is in permissive */ ebitmap_for_each_bit(&policydb->permissive_map, n, bit) { if (ebitmap_node_get_bit(n, bit)) { printf("%s\n", policydb->p_type_val_to_name[bit -1]); } } return 0; } static int read_typeset(policydb_t *policydb, char **ptr, char *end, type_set_t *typeset, uint32_t *flags) { const char *keyword = "self"; size_t keyword_size = strlen(keyword), len; char *p = *ptr; unsigned openparens = 0; char *start, *id; type_datum_t *type; struct ebitmap_node *n; unsigned int bit; bool negate = false; int rc; do { while (p < end && isspace(*p)) p++; if (p == end) goto err; if (*p == '~') { if (debug) printf(" ~"); typeset->flags = TYPE_COMP; p++; while (p < end && isspace(*p)) p++; if (p == end) goto err; } if (*p == '{') { if (debug && !openparens) printf(" {"); openparens++; p++; continue; } if (*p == '}') { if (debug && openparens == 1) printf(" }"); if (openparens == 0) goto err; openparens--; p++; continue; } if (*p == '*') { if (debug) printf(" *"); typeset->flags = TYPE_STAR; p++; continue; } if (*p == '-') { if (debug) printf(" -"); negate = true; p++; continue; } if (*p == '#') { while (p < end && *p != '\n') p++; continue; } start = p; while (p < end && !isspace(*p) && *p != ':' && *p != ';' && *p != '{' && *p != '}' && *p != '#') p++; if (p == start) goto err; len = p - start; if (len == keyword_size && !strncmp(start, keyword, keyword_size)) { if (debug) printf(" self"); *flags |= RULE_SELF; continue; } id = calloc(1, len + 1); if (!id) goto err; memcpy(id, start, len); if (debug) printf(" %s", id); type = hashtab_search(policydb->p_types.table, id); if (!type) { if (warn) fprintf(stderr, "Warning! Type or attribute %s used in neverallow undefined in policy being checked.\n", id); negate = false; continue; } free(id); if (type->flavor == TYPE_ATTRIB) { if (negate) rc = ebitmap_union(&typeset->negset, &policydb->attr_type_map[type->s.value - 1]); else rc = ebitmap_union(&typeset->types, &policydb->attr_type_map[type->s.value - 1]); } else if (negate) { rc = ebitmap_set_bit(&typeset->negset, type->s.value - 1, 1); } else { rc = ebitmap_set_bit(&typeset->types, type->s.value - 1, 1); } negate = false; if (rc) goto err; } while (p < end && openparens); if (p == end) goto err; if (typeset->flags & TYPE_STAR) { for (bit = 0; bit < policydb->p_types.nprim; bit++) { if (ebitmap_get_bit(&typeset->negset, bit)) continue; if (policydb->type_val_to_struct[bit] && policydb->type_val_to_struct[bit]->flavor == TYPE_ATTRIB) continue; if (ebitmap_set_bit(&typeset->types, bit, 1)) goto err; } } ebitmap_for_each_bit(&typeset->negset, n, bit) { if (!ebitmap_node_get_bit(n, bit)) continue; if (ebitmap_set_bit(&typeset->types, bit, 0)) goto err; } if (typeset->flags & TYPE_COMP) { for (bit = 0; bit < policydb->p_types.nprim; bit++) { if (policydb->type_val_to_struct[bit] && policydb->type_val_to_struct[bit]->flavor == TYPE_ATTRIB) continue; if (ebitmap_get_bit(&typeset->types, bit)) ebitmap_set_bit(&typeset->types, bit, 0); else { if (ebitmap_set_bit(&typeset->types, bit, 1)) goto err; } } } if (warn && ebitmap_length(&typeset->types) == 0 && !(*flags)) fprintf(stderr, "Warning! Empty type set\n"); *ptr = p; return 0; err: return -1; } static int read_classperms(policydb_t *policydb, char **ptr, char *end, class_perm_node_t **perms) { char *p = *ptr; unsigned openparens = 0; char *id, *start; class_datum_t *cls = NULL; perm_datum_t *perm = NULL; class_perm_node_t *classperms = NULL, *node = NULL; bool complement = false; while (p < end && isspace(*p)) p++; if (p == end || *p != ':') goto err; p++; if (debug) printf(" :"); do { while (p < end && isspace(*p)) p++; if (p == end) goto err; if (*p == '{') { if (debug && !openparens) printf(" {"); openparens++; p++; continue; } if (*p == '}') { if (debug && openparens == 1) printf(" }"); if (openparens == 0) goto err; openparens--; p++; continue; } if (*p == '#') { while (p < end && *p != '\n') p++; continue; } start = p; while (p < end && !isspace(*p) && *p != '{' && *p != '}' && *p != ';' && *p != '#') p++; if (p == start) goto err; id = calloc(1, p - start + 1); if (!id) goto err; memcpy(id, start, p - start); if (debug) printf(" %s", id); cls = hashtab_search(policydb->p_classes.table, id); if (!cls) { if (warn) fprintf(stderr, "Warning! Class %s used in neverallow undefined in policy being checked.\n", id); continue; } node = calloc(1, sizeof *node); if (!node) goto err; node->class = cls->s.value; node->next = classperms; classperms = node; free(id); } while (p < end && openparens); if (p == end) goto err; if (warn && !classperms) fprintf(stderr, "Warning! Empty class set\n"); do { while (p < end && isspace(*p)) p++; if (p == end) goto err; if (*p == '~') { if (debug) printf(" ~"); complement = true; p++; while (p < end && isspace(*p)) p++; if (p == end) goto err; } if (*p == '{') { if (debug && !openparens) printf(" {"); openparens++; p++; continue; } if (*p == '}') { if (debug && openparens == 1) printf(" }"); if (openparens == 0) goto err; openparens--; p++; continue; } if (*p == '#') { while (p < end && *p != '\n') p++; continue; } start = p; while (p < end && !isspace(*p) && *p != '{' && *p != '}' && *p != ';' && *p != '#') p++; if (p == start) goto err; id = calloc(1, p - start + 1); if (!id) goto err; memcpy(id, start, p - start); if (debug) printf(" %s", id); if (!strcmp(id, "*")) { for (node = classperms; node; node = node->next) node->data = ~0; continue; } for (node = classperms; node; node = node->next) { cls = policydb->class_val_to_struct[node->class-1]; perm = hashtab_search(cls->permissions.table, id); if (cls->comdatum && !perm) perm = hashtab_search(cls->comdatum->permissions.table, id); if (!perm) { if (warn) fprintf(stderr, "Warning! Permission %s used in neverallow undefined in class %s in policy being checked.\n", id, policydb->p_class_val_to_name[node->class-1]); continue; } node->data |= 1U << (perm->s.value - 1); } free(id); } while (p < end && openparens); if (p == end) goto err; if (complement) { for (node = classperms; node; node = node->next) node->data = ~node->data; } if (warn) { for (node = classperms; node; node = node->next) if (!node->data) fprintf(stderr, "Warning! Empty permission set\n"); } *perms = classperms; *ptr = p; return 0; err: return -1; } static int check_neverallows(policydb_t *policydb, const char *filename) { const char *keyword = "neverallow"; size_t keyword_size = strlen(keyword), len; struct avrule *neverallows = NULL, *avrule; int fd; struct stat sb; char *text, *end, *start; char *p; fd = open(filename, O_RDONLY); if (fd < 0) { fprintf(stderr, "Could not open %s: %s\n", filename, strerror(errno)); return -1; } if (fstat(fd, &sb) < 0) { fprintf(stderr, "Can't stat '%s': %s\n", filename, strerror(errno)); close(fd); return -1; } text = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0); end = text + sb.st_size; if (text == MAP_FAILED) { fprintf(stderr, "Can't mmap '%s': %s\n", filename, strerror(errno)); close(fd); return -1; } close(fd); p = text; while (p < end) { while (p < end && isspace(*p)) p++; if (*p == '#') { while (p < end && *p != '\n') p++; continue; } start = p; while (p < end && !isspace(*p)) p++; len = p - start; if (len != keyword_size || strncmp(start, keyword, keyword_size)) continue; if (debug) printf("neverallow"); avrule = calloc(1, sizeof *avrule); if (!avrule) goto err; avrule->specified = AVRULE_NEVERALLOW; if (read_typeset(policydb, &p, end, &avrule->stypes, &avrule->flags)) goto err; if (read_typeset(policydb, &p, end, &avrule->ttypes, &avrule->flags)) goto err; if (read_classperms(policydb, &p, end, &avrule->perms)) goto err; while (p < end && *p != ';') p++; if (p == end || *p != ';') goto err; if (debug) printf(";\n"); avrule->next = neverallows; neverallows = avrule; } return check_assertions(NULL, policydb, neverallows); err: if (errno == ENOMEM) { fprintf(stderr, "Out of memory while parsing %s\n", filename); } else fprintf(stderr, "Error while parsing %s\n", filename); return -1; } int main(int argc, char **argv) { char *policy = NULL, *neverallows = NULL; struct policy_file pf; policydb_t policydb; char ch; char equiv = 0, diff = 0, dups = 0, permissive = 0; int rc = 0; struct option long_options[] = { {"equiv", no_argument, NULL, 'e'}, {"debug", no_argument, NULL, 'z'}, {"diff", no_argument, NULL, 'd'}, {"dups", no_argument, NULL, 'D'}, {"neverallow", required_argument, NULL, 'n'}, {"permissive", no_argument, NULL, 'p'}, {"policy", required_argument, NULL, 'P'}, {"warn", no_argument, NULL, 'w'}, {NULL, 0, NULL, 0} }; while ((ch = getopt_long(argc, argv, "edDpn:P:wz", long_options, NULL)) != -1) { switch (ch) { case 'e': equiv = 1; break; case 'd': diff = 1; break; case 'D': dups = 1; break; case 'n': neverallows = optarg; break; case 'p': permissive = 1; break; case 'P': policy = optarg; break; case 'w': warn = 1; break; case 'z': debug = 1; break; default: usage(argv[0]); } } if (!policy || (!equiv && !diff && !dups && !permissive && !neverallows)) usage(argv[0]); if (load_policy(policy, &policydb, &pf)) exit(1); if (equiv || diff) analyze_types(&policydb, equiv, diff); if (dups) find_dups(&policydb); if (permissive) list_permissive(&policydb); if (neverallows) rc |= check_neverallows(&policydb, neverallows); policydb_destroy(&policydb); return rc; }