/* * udev_rules_parse.c * * Userspace devfs * * Copyright (C) 2003,2004 Greg Kroah-Hartman * Copyright (C) 2003-2005 Kay Sievers * * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation version 2 of the License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 675 Mass Ave, Cambridge, MA 02139, USA. * */ #include #include #include #include #include #include #include #include #include "udev_libc_wrapper.h" #include "udev.h" #include "udev_utils.h" #include "logging.h" #include "udev_rules.h" void udev_rules_iter_init(struct udev_rules *rules) { dbg("bufsize=%zi", rules->bufsize); rules->current = 0; } struct udev_rule *udev_rules_iter_next(struct udev_rules *rules) { static struct udev_rule *rule; if (!rules) return NULL; dbg("current=%zi", rules->current); if (rules->current >= rules->bufsize) return NULL; /* get next rule */ rule = (struct udev_rule *) (rules->buf + rules->current); rules->current += sizeof(struct udev_rule) + rule->bufsize; return rule; } static int get_key(char **line, char **key, enum key_operation *operation, char **value) { char *linepos; char *temp; linepos = *line; if (!linepos) return -1; /* skip whitespace */ while (isspace(linepos[0]) || linepos[0] == ',') linepos++; /* get the key */ *key = linepos; while (1) { linepos++; if (linepos[0] == '\0') return -1; if (isspace(linepos[0])) break; if (linepos[0] == '=') break; if (linepos[0] == '+') break; if (linepos[0] == '!') break; if (linepos[0] == ':') break; } /* remember end of key */ temp = linepos; /* skip whitespace after key */ while (isspace(linepos[0])) linepos++; /* get operation type */ if (linepos[0] == '=' && linepos[1] == '=') { *operation = KEY_OP_MATCH; linepos += 2; dbg("operator=match"); } else if (linepos[0] == '!' && linepos[1] == '=') { *operation = KEY_OP_NOMATCH; linepos += 2; dbg("operator=nomatch"); } else if (linepos[0] == '+' && linepos[1] == '=') { *operation = KEY_OP_ADD; linepos += 2; dbg("operator=add"); } else if (linepos[0] == '=') { *operation = KEY_OP_ASSIGN; linepos++; dbg("operator=assign"); } else if (linepos[0] == ':' && linepos[1] == '=') { *operation = KEY_OP_ASSIGN_FINAL; linepos += 2; dbg("operator=assign_final"); } else return -1; /* terminate key */ temp[0] = '\0'; dbg("key='%s'", *key); /* skip whitespace after operator */ while (isspace(linepos[0])) linepos++; /* get the value*/ if (linepos[0] == '"') linepos++; else return -1; *value = linepos; temp = strchr(linepos, '"'); if (!temp) return -1; temp[0] = '\0'; temp++; dbg("value='%s'", *value); /* move line to next key */ *line = temp; return 0; } /* extract possible KEY{attr} */ static char *get_key_attribute(char *str) { char *pos; char *attr; attr = strchr(str, '{'); if (attr != NULL) { attr++; pos = strchr(attr, '}'); if (pos == NULL) { err("missing closing brace for format"); return NULL; } pos[0] = '\0'; dbg("attribute='%s'", attr); return attr; } return NULL; } static int add_rule_key(struct udev_rule *rule, struct key *key, enum key_operation operation, const char *value) { size_t val_len = strnlen(value, PATH_SIZE); key->operation = operation; key->val_off = rule->bufsize; strlcpy(rule->buf + rule->bufsize, value, val_len+1); rule->bufsize += val_len+1; return 0; } static int add_rule_key_pair(struct udev_rule *rule, struct key_pairs *pairs, enum key_operation operation, const char *key, const char *value) { size_t key_len = strnlen(key, PATH_SIZE); if (pairs->count >= PAIRS_MAX) { err("skip, too many keys in a single rule"); return -1; } add_rule_key(rule, &pairs->keys[pairs->count].key, operation, value); /* add the key-name of the pair */ pairs->keys[pairs->count].key_name_off = rule->bufsize; strlcpy(rule->buf + rule->bufsize, key, key_len+1); rule->bufsize += key_len+1; pairs->count++; return 0; } static int add_to_rules(struct udev_rules *rules, char *line) { struct udev_rule *rule; size_t rule_size; int valid; char *linepos; char *attr; int retval; /* get all the keys */ rule = calloc(1, sizeof (struct udev_rule) + LINE_SIZE); if (!rule) { err("malloc failed"); return -1; } linepos = line; valid = 0; while (1) { char *key; char *value; enum key_operation operation = KEY_OP_UNSET; retval = get_key(&linepos, &key, &operation, &value); if (retval) break; if (strcasecmp(key, "KERNEL") == 0) { add_rule_key(rule, &rule->kernel_name, operation, value); valid = 1; continue; } if (strcasecmp(key, "SUBSYSTEM") == 0) { add_rule_key(rule, &rule->subsystem, operation, value); valid = 1; continue; } if (strcasecmp(key, "ACTION") == 0) { add_rule_key(rule, &rule->action, operation, value); valid = 1; continue; } if (strcasecmp(key, "DEVPATH") == 0) { add_rule_key(rule, &rule->devpath, operation, value); valid = 1; continue; } if (strcasecmp(key, "BUS") == 0) { add_rule_key(rule, &rule->bus, operation, value); valid = 1; continue; } if (strcasecmp(key, "ID") == 0) { add_rule_key(rule, &rule->id, operation, value); valid = 1; continue; } if (strncasecmp(key, "SYSFS", sizeof("SYSFS")-1) == 0) { attr = get_key_attribute(key + sizeof("SYSFS")-1); if (attr == NULL) { err("error parsing SYSFS attribute in '%s'", line); continue; } add_rule_key_pair(rule, &rule->sysfs, operation, attr, value); valid = 1; continue; } if (strncasecmp(key, "ENV", sizeof("ENV")-1) == 0) { attr = get_key_attribute(key + sizeof("ENV")-1); if (attr == NULL) { err("error parsing ENV attribute"); continue; } add_rule_key_pair(rule, &rule->env, operation, attr, value); valid = 1; continue; } if (strcasecmp(key, "MODALIAS") == 0) { add_rule_key(rule, &rule->modalias, operation, value); valid = 1; continue; } if (strncasecmp(key, "IMPORT", sizeof("IMPORT")-1) == 0) { attr = get_key_attribute(key + sizeof("IMPORT")-1); if (attr && strstr(attr, "program")) { dbg("IMPORT will be executed"); rule->import_exec = 1; } else if (attr && strstr(attr, "file")) { dbg("IMPORT will be included as file"); } else { /* figure it out if it is executable */ char file[PATH_SIZE]; char *pos; struct stat stats; strlcpy(file, value, sizeof(file)); pos = strchr(file, ' '); if (pos) pos[0] = '\0'; dbg("IMPORT auto mode for '%s'", file); if (!lstat(file, &stats) && (stats.st_mode & S_IXUSR)) { dbg("IMPORT is executable, will be executed"); rule->import_exec = 1; } } add_rule_key(rule, &rule->import, operation, value); valid = 1; continue; } if (strcasecmp(key, "DRIVER") == 0) { add_rule_key(rule, &rule->driver, operation, value); valid = 1; continue; } if (strcasecmp(key, "RESULT") == 0) { add_rule_key(rule, &rule->result, operation, value); valid = 1; continue; } if (strcasecmp(key, "PROGRAM") == 0) { add_rule_key(rule, &rule->program, operation, value); valid = 1; continue; } if (strncasecmp(key, "NAME", sizeof("NAME")-1) == 0) { attr = get_key_attribute(key + sizeof("NAME")-1); if (attr != NULL) { if (strstr(attr, "all_partitions") != NULL) { dbg("creation of partition nodes requested"); rule->partitions = DEFAULT_PARTITIONS_COUNT; } if (strstr(attr, "ignore_remove") != NULL) { dbg("remove event should be ignored"); rule->ignore_remove = 1; } } add_rule_key(rule, &rule->name, operation, value); continue; } if (strcasecmp(key, "SYMLINK") == 0) { add_rule_key(rule, &rule->symlink, operation, value); valid = 1; continue; } if (strcasecmp(key, "OWNER") == 0) { valid = 1; if (rules->resolve_names) { char *endptr; strtoul(value, &endptr, 10); if (endptr[0] != '\0') { char owner[32]; uid_t uid = lookup_user(value); dbg("replacing username='%s' by id=%i", value, uid); sprintf(owner, "%li", uid); add_rule_key(rule, &rule->owner, operation, owner); continue; } } add_rule_key(rule, &rule->owner, operation, value); continue; } if (strcasecmp(key, "GROUP") == 0) { valid = 1; if (rules->resolve_names) { char *endptr; strtoul(value, &endptr, 10); if (endptr[0] != '\0') { char group[32]; gid_t gid = lookup_group(value); dbg("replacing groupname='%s' by id=%i", value, gid); sprintf(group, "%li", gid); add_rule_key(rule, &rule->owner, operation, group); continue; } } add_rule_key(rule, &rule->group, operation, value); continue; } if (strcasecmp(key, "MODE") == 0) { rule->mode = strtol(value, NULL, 8); rule->mode_operation = operation; valid = 1; continue; } if (strcasecmp(key, "RUN") == 0) { add_rule_key(rule, &rule->run, operation, value); valid = 1; continue; } if (strcasecmp(key, "OPTIONS") == 0) { if (strstr(value, "last_rule") != NULL) { dbg("last rule to be applied"); rule->last_rule = 1; } if (strstr(value, "ignore_device") != NULL) { dbg("device should be ignored"); rule->ignore_device = 1; } if (strstr(value, "ignore_remove") != NULL) { dbg("remove event should be ignored"); rule->ignore_remove = 1; } if (strstr(value, "all_partitions") != NULL) { dbg("creation of partition nodes requested"); rule->partitions = DEFAULT_PARTITIONS_COUNT; } valid = 1; continue; } err("unknown key '%s', in '%s'", key, line); } /* skip line if not any valid key was found */ if (!valid) { err("invalid rule '%s'", line); goto exit; } /* grow buffer and add rule */ rule_size = sizeof(struct udev_rule) + rule->bufsize; rules->buf = realloc(rules->buf, rules->bufsize + rule_size); if (!rules->buf) { err("realloc failed"); goto exit; } memcpy(rules->buf + rules->bufsize, rule, rule_size); rules->bufsize += rule_size; exit: free(rule); return 0; } static int parse_file(struct udev_rules *rules, const char *filename) { char line[LINE_SIZE]; char *bufline; int lineno; char *buf; size_t bufsize; size_t cur; size_t count; int retval = 0; if (file_map(filename, &buf, &bufsize) != 0) { err("can't open '%s' as rules file", filename); return -1; } dbg("reading '%s' as rules file", filename); /* loop through the whole file */ cur = 0; lineno = 0; while (cur < bufsize) { unsigned int i, j; count = buf_get_line(buf, bufsize, cur); bufline = &buf[cur]; cur += count+1; lineno++; if (count >= sizeof(line)) { info("line too long, rule skipped %s, line %d", filename, lineno); continue; } /* eat the whitespace */ while ((count > 0) && isspace(bufline[0])) { bufline++; count--; } if (count == 0) continue; /* see if this is a comment */ if (bufline[0] == COMMENT_CHARACTER) continue; /* skip backslash and newline from multi line rules */ for (i = j = 0; i < count; i++) { if (bufline[i] == '\\' && bufline[i+1] == '\n') continue; line[j++] = bufline[i]; } line[j] = '\0'; dbg("read '%s'", line); add_to_rules(rules, line); } file_unmap(buf, bufsize); return retval; } static int rules_map(struct udev_rules *rules, const char *filename) { if (file_map(filename, &rules->buf, &rules->bufsize)) { rules->buf = NULL; return -1; } if (rules->bufsize == 0) { file_unmap(rules->buf, rules->bufsize); rules->buf = NULL; return -1; } return 0; } int udev_rules_init(struct udev_rules *rules, int resolve_names) { char comp[PATH_SIZE]; struct stat stats; int retval; memset(rules, 0x00, sizeof(struct udev_rules)); rules->resolve_names = resolve_names; /* check for precompiled rules */ strlcpy(comp, udev_rules_filename, sizeof(comp)); strlcat(comp, ".compiled", sizeof(comp)); if (stat(comp, &stats) == 0) { dbg("map compiled rules '%s'", comp); if (rules_map(rules, comp) == 0) return 0; } if (stat(udev_rules_filename, &stats) != 0) return -1; if ((stats.st_mode & S_IFMT) != S_IFDIR) { dbg("parse single rules file '%s'", udev_rules_filename); retval = parse_file(rules, udev_rules_filename); } else { struct name_entry *name_loop, *name_tmp; LIST_HEAD(name_list); dbg("parse rules directory '%s'", udev_rules_filename); retval = add_matching_files(&name_list, udev_rules_filename, RULEFILE_SUFFIX); list_for_each_entry_safe(name_loop, name_tmp, &name_list, node) { parse_file(rules, name_loop->name); list_del(&name_loop->node); } } return retval; } void udev_rules_close(struct udev_rules *rules) { if (rules->mapped) file_unmap(rules->buf, rules->bufsize); else free(rules->buf); rules->buf = NULL; }