/* * Copyright (C) 2003-2010 Kay Sievers <kay.sievers@vrfy.org> * * 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, either version 2 of the License, or * (at your option) any later version. * * 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, see <http://www.gnu.org/licenses/>. */ #include <stdlib.h> #include <stdio.h> #include <stddef.h> #include <unistd.h> #include <fcntl.h> #include <errno.h> #include <ctype.h> #include <string.h> #include <time.h> #include <net/if.h> #include <sys/ioctl.h> #include <sys/socket.h> #include <linux/sockios.h> #include "udev.h" struct udev_event *udev_event_new(struct udev_device *dev) { struct udev_event *event; event = calloc(1, sizeof(struct udev_event)); if (event == NULL) return NULL; event->mode = 0600; event->dev = dev; event->udev = udev_device_get_udev(dev); udev_list_init(&event->run_list); dbg(event->udev, "allocated event %p\n", event); return event; } void udev_event_unref(struct udev_event *event) { if (event == NULL) return; udev_list_cleanup_entries(event->udev, &event->run_list); free(event->tmp_node); free(event->program_result); free(event->name); dbg(event->udev, "free event %p\n", event); free(event); } size_t udev_event_apply_format(struct udev_event *event, const char *src, char *dest, size_t size) { struct udev_device *dev = event->dev; enum subst_type { SUBST_UNKNOWN, SUBST_TEMP_NODE, SUBST_ATTR, SUBST_ENV, SUBST_KERNEL, SUBST_KERNEL_NUMBER, SUBST_DRIVER, SUBST_DEVPATH, SUBST_ID, SUBST_MAJOR, SUBST_MINOR, SUBST_RESULT, SUBST_PARENT, SUBST_NAME, SUBST_LINKS, SUBST_ROOT, SUBST_SYS, }; static const struct subst_map { char *name; char fmt; enum subst_type type; } map[] = { { .name = "tempnode", .fmt = 'N', .type = SUBST_TEMP_NODE }, { .name = "attr", .fmt = 's', .type = SUBST_ATTR }, { .name = "sysfs", .fmt = 's', .type = SUBST_ATTR }, { .name = "env", .fmt = 'E', .type = SUBST_ENV }, { .name = "kernel", .fmt = 'k', .type = SUBST_KERNEL }, { .name = "number", .fmt = 'n', .type = SUBST_KERNEL_NUMBER }, { .name = "driver", .fmt = 'd', .type = SUBST_DRIVER }, { .name = "devpath", .fmt = 'p', .type = SUBST_DEVPATH }, { .name = "id", .fmt = 'b', .type = SUBST_ID }, { .name = "major", .fmt = 'M', .type = SUBST_MAJOR }, { .name = "minor", .fmt = 'm', .type = SUBST_MINOR }, { .name = "result", .fmt = 'c', .type = SUBST_RESULT }, { .name = "parent", .fmt = 'P', .type = SUBST_PARENT }, { .name = "name", .fmt = 'D', .type = SUBST_NAME }, { .name = "links", .fmt = 'L', .type = SUBST_LINKS }, { .name = "root", .fmt = 'r', .type = SUBST_ROOT }, { .name = "sys", .fmt = 'S', .type = SUBST_SYS }, }; const char *from; char *s; size_t l; from = src; s = dest; l = size; for (;;) { enum subst_type type = SUBST_UNKNOWN; char attrbuf[UTIL_PATH_SIZE]; char *attr = NULL; while (from[0] != '\0') { if (from[0] == '$') { /* substitute named variable */ unsigned int i; if (from[1] == '$') { from++; goto copy; } for (i = 0; i < ARRAY_SIZE(map); i++) { if (strncmp(&from[1], map[i].name, strlen(map[i].name)) == 0) { type = map[i].type; from += strlen(map[i].name)+1; dbg(event->udev, "will substitute format name '%s'\n", map[i].name); goto subst; } } } else if (from[0] == '%') { /* substitute format char */ unsigned int i; if (from[1] == '%') { from++; goto copy; } for (i = 0; i < ARRAY_SIZE(map); i++) { if (from[1] == map[i].fmt) { type = map[i].type; from += 2; dbg(event->udev, "will substitute format char '%c'\n", map[i].fmt); goto subst; } } } copy: /* copy char */ if (l == 0) goto out; s[0] = from[0]; from++; s++; l--; } goto out; subst: /* extract possible $format{attr} */ if (from[0] == '{') { unsigned int i; from++; for (i = 0; from[i] != '}'; i++) { if (from[i] == '\0') { err(event->udev, "missing closing brace for format '%s'\n", src); goto out; } } if (i >= sizeof(attrbuf)) goto out; memcpy(attrbuf, from, i); attrbuf[i] = '\0'; from += i+1; attr = attrbuf; } else { attr = NULL; } switch (type) { case SUBST_DEVPATH: l = util_strpcpy(&s, l, udev_device_get_devpath(dev)); dbg(event->udev, "substitute devpath '%s'\n", udev_device_get_devpath(dev)); break; case SUBST_KERNEL: l = util_strpcpy(&s, l, udev_device_get_sysname(dev)); dbg(event->udev, "substitute kernel name '%s'\n", udev_device_get_sysname(dev)); break; case SUBST_KERNEL_NUMBER: if (udev_device_get_sysnum(dev) == NULL) break; l = util_strpcpy(&s, l, udev_device_get_sysnum(dev)); dbg(event->udev, "substitute kernel number '%s'\n", udev_device_get_sysnum(dev)); break; case SUBST_ID: if (event->dev_parent == NULL) break; l = util_strpcpy(&s, l, udev_device_get_sysname(event->dev_parent)); dbg(event->udev, "substitute id '%s'\n", udev_device_get_sysname(event->dev_parent)); break; case SUBST_DRIVER: { const char *driver; if (event->dev_parent == NULL) break; driver = udev_device_get_driver(event->dev_parent); if (driver == NULL) break; l = util_strpcpy(&s, l, driver); dbg(event->udev, "substitute driver '%s'\n", driver); break; } case SUBST_MAJOR: { char num[UTIL_PATH_SIZE]; sprintf(num, "%d", major(udev_device_get_devnum(dev))); l = util_strpcpy(&s, l, num); dbg(event->udev, "substitute major number '%s'\n", num); break; } case SUBST_MINOR: { char num[UTIL_PATH_SIZE]; sprintf(num, "%d", minor(udev_device_get_devnum(dev))); l = util_strpcpy(&s, l, num); dbg(event->udev, "substitute minor number '%s'\n", num); break; } case SUBST_RESULT: { char *rest; int i; if (event->program_result == NULL) break; /* get part part of the result string */ i = 0; if (attr != NULL) i = strtoul(attr, &rest, 10); if (i > 0) { char result[UTIL_PATH_SIZE]; char tmp[UTIL_PATH_SIZE]; char *cpos; dbg(event->udev, "request part #%d of result string\n", i); util_strscpy(result, sizeof(result), event->program_result); cpos = result; while (--i) { while (cpos[0] != '\0' && !isspace(cpos[0])) cpos++; while (isspace(cpos[0])) cpos++; } if (i > 0) { err(event->udev, "requested part of result string not found\n"); break; } util_strscpy(tmp, sizeof(tmp), cpos); /* %{2+}c copies the whole string from the second part on */ if (rest[0] != '+') { cpos = strchr(tmp, ' '); if (cpos) cpos[0] = '\0'; } l = util_strpcpy(&s, l, tmp); dbg(event->udev, "substitute part of result string '%s'\n", tmp); } else { l = util_strpcpy(&s, l, event->program_result); dbg(event->udev, "substitute result string '%s'\n", event->program_result); } break; } case SUBST_ATTR: { const char *value = NULL; char vbuf[UTIL_NAME_SIZE]; size_t len; int count; if (attr == NULL) { err(event->udev, "missing file parameter for attr\n"); break; } /* try to read the value specified by "[dmi/id]product_name" */ if (util_resolve_subsys_kernel(event->udev, attr, vbuf, sizeof(vbuf), 1) == 0) value = vbuf; /* try to read the attribute the device */ if (value == NULL) value = udev_device_get_sysattr_value(event->dev, attr); /* try to read the attribute of the parent device, other matches have selected */ if (value == NULL && event->dev_parent != NULL && event->dev_parent != event->dev) value = udev_device_get_sysattr_value(event->dev_parent, attr); if (value == NULL) break; /* strip trailing whitespace, and replace unwanted characters */ if (value != vbuf) util_strscpy(vbuf, sizeof(vbuf), value); len = strlen(vbuf); while (len > 0 && isspace(vbuf[--len])) vbuf[len] = '\0'; count = udev_util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT); if (count > 0) info(event->udev, "%i character(s) replaced\n" , count); l = util_strpcpy(&s, l, vbuf); dbg(event->udev, "substitute sysfs value '%s'\n", vbuf); break; } case SUBST_PARENT: { struct udev_device *dev_parent; const char *devnode; dev_parent = udev_device_get_parent(event->dev); if (dev_parent == NULL) break; devnode = udev_device_get_devnode(dev_parent); if (devnode != NULL) { size_t devlen = strlen(udev_get_dev_path(event->udev))+1; l = util_strpcpy(&s, l, &devnode[devlen]); dbg(event->udev, "found parent '%s', got node name '%s'\n", udev_device_get_syspath(dev_parent), &devnode[devlen]); } break; } case SUBST_TEMP_NODE: { dev_t devnum; struct stat statbuf; char filename[UTIL_PATH_SIZE]; const char *devtype; if (event->tmp_node != NULL) { l = util_strpcpy(&s, l, event->tmp_node); dbg(event->udev, "tempnode: return earlier created one\n"); break; } devnum = udev_device_get_devnum(dev); if (major(devnum) == 0) break; /* lookup kernel provided node */ if (udev_device_get_knodename(dev) != NULL) { util_strscpyl(filename, sizeof(filename), udev_get_dev_path(event->udev), "/", udev_device_get_knodename(dev), NULL); if (stat(filename, &statbuf) == 0 && statbuf.st_rdev == devnum) { l = util_strpcpy(&s, l, filename); dbg(event->udev, "tempnode: return kernel node\n"); break; } } /* lookup /dev/{char,block}/<maj>:<min> */ if (strcmp(udev_device_get_subsystem(dev), "block") == 0) devtype = "block"; else devtype = "char"; snprintf(filename, sizeof(filename), "%s/%s/%u:%u", udev_get_dev_path(event->udev), devtype, major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev))); if (stat(filename, &statbuf) == 0 && statbuf.st_rdev == devnum) { l = util_strpcpy(&s, l, filename); dbg(event->udev, "tempnode: return maj:min node\n"); break; } /* create temporary node */ dbg(event->udev, "tempnode: create temp node\n"); asprintf(&event->tmp_node, "%s/.tmp-%s-%u:%u", udev_get_dev_path(event->udev), devtype, major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev))); if (event->tmp_node == NULL) break; udev_node_mknod(dev, event->tmp_node, 0600, 0, 0); l = util_strpcpy(&s, l, event->tmp_node); break; } case SUBST_NAME: if (event->name != NULL) { l = util_strpcpy(&s, l, event->name); dbg(event->udev, "substitute name '%s'\n", event->name); } else { l = util_strpcpy(&s, l, udev_device_get_sysname(dev)); dbg(event->udev, "substitute sysname '%s'\n", udev_device_get_sysname(dev)); } break; case SUBST_LINKS: { size_t devlen = strlen(udev_get_dev_path(event->udev))+1; struct udev_list_entry *list_entry; list_entry = udev_device_get_devlinks_list_entry(dev); if (list_entry == NULL) break; l = util_strpcpy(&s, l, &udev_list_entry_get_name(list_entry)[devlen]); udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry)) l = util_strpcpyl(&s, l, " ", &udev_list_entry_get_name(list_entry)[devlen], NULL); break; } case SUBST_ROOT: l = util_strpcpy(&s, l, udev_get_dev_path(event->udev)); dbg(event->udev, "substitute udev_root '%s'\n", udev_get_dev_path(event->udev)); break; case SUBST_SYS: l = util_strpcpy(&s, l, udev_get_sys_path(event->udev)); dbg(event->udev, "substitute sys_path '%s'\n", udev_get_sys_path(event->udev)); break; case SUBST_ENV: if (attr == NULL) { dbg(event->udev, "missing attribute\n"); break; } else { const char *value; value = udev_device_get_property_value(event->dev, attr); if (value == NULL) break; dbg(event->udev, "substitute env '%s=%s'\n", attr, value); l = util_strpcpy(&s, l, value); break; } default: err(event->udev, "unknown substitution type=%i\n", type); break; } } out: s[0] = '\0'; dbg(event->udev, "'%s' -> '%s' (%zu)\n", src, dest, l); return l; } static void rename_netif_kernel_log(struct ifreq ifr) { int klog; FILE *f; klog = open("/dev/kmsg", O_WRONLY); if (klog < 0) return; f = fdopen(klog, "w"); if (f == NULL) { close(klog); return; } fprintf(f, "<6>udev: renamed network interface %s to %s\n", ifr.ifr_name, ifr.ifr_newname); fclose(f); } static int rename_netif(struct udev_event *event) { struct udev_device *dev = event->dev; int sk; struct ifreq ifr; int err; info(event->udev, "changing net interface name from '%s' to '%s'\n", udev_device_get_sysname(dev), event->name); sk = socket(PF_INET, SOCK_DGRAM, 0); if (sk < 0) { err(event->udev, "error opening socket: %m\n"); return -1; } memset(&ifr, 0x00, sizeof(struct ifreq)); util_strscpy(ifr.ifr_name, IFNAMSIZ, udev_device_get_sysname(dev)); util_strscpy(ifr.ifr_newname, IFNAMSIZ, event->name); err = ioctl(sk, SIOCSIFNAME, &ifr); if (err == 0) rename_netif_kernel_log(ifr); else { int loop; /* see if the destination interface name already exists */ if (errno != EEXIST) { err(event->udev, "error changing netif name %s to %s: %m\n", ifr.ifr_name, ifr.ifr_newname); goto exit; } /* free our own name, another process may wait for us */ util_strscpyl(ifr.ifr_newname, IFNAMSIZ, udev_device_get_sysname(dev), "_rename", NULL); err = ioctl(sk, SIOCSIFNAME, &ifr); if (err != 0) { err(event->udev, "error changing netif name %s to %s: %m\n", ifr.ifr_name, ifr.ifr_newname); goto exit; } /* wait 90 seconds for our target to become available */ util_strscpy(ifr.ifr_name, IFNAMSIZ, ifr.ifr_newname); util_strscpy(ifr.ifr_newname, IFNAMSIZ, event->name); loop = 90 * 20; while (loop--) { const struct timespec duration = { 0, 1000 * 1000 * 1000 / 20 }; err = ioctl(sk, SIOCSIFNAME, &ifr); if (err == 0) { rename_netif_kernel_log(ifr); break; } if (errno != EEXIST) { err(event->udev, "error changing net interface name %s to %s: %m\n", ifr.ifr_name, ifr.ifr_newname); break; } dbg(event->udev, "wait for netif '%s' to become free, loop=%i\n", event->name, (90 * 20) - loop); nanosleep(&duration, NULL); } } exit: close(sk); return err; } int udev_event_execute_rules(struct udev_event *event, struct udev_rules *rules) { struct udev_device *dev = event->dev; int err = 0; if (udev_device_get_sysname_old(dev) != NULL && strcmp(udev_device_get_sysname_old(dev), udev_device_get_sysname(dev)) != 0) { udev_device_rename_db(dev); info(event->udev, "moved database from '%s:%s' to '%s:%s'\n", udev_device_get_subsystem(dev), udev_device_get_sysname_old(dev), udev_device_get_subsystem(dev), udev_device_get_sysname(dev)); } if (strcmp(udev_device_get_action(dev), "remove") == 0) { udev_device_read_db(dev); udev_device_delete_db(dev); udev_device_tag_index(dev, NULL, false); if (major(udev_device_get_devnum(dev)) != 0) udev_watch_end(event->udev, dev); udev_rules_apply_to_event(rules, event); if (major(udev_device_get_devnum(dev)) != 0) err = udev_node_remove(dev); } else { event->dev_db = udev_device_new_from_syspath(event->udev, udev_device_get_syspath(dev)); if (event->dev_db != NULL) { udev_device_read_db(event->dev_db); udev_device_set_info_loaded(event->dev_db); /* disable watch during event processing */ if (major(udev_device_get_devnum(dev)) != 0) udev_watch_end(event->udev, event->dev_db); } udev_rules_apply_to_event(rules, event); /* rename a new network interface, if needed */ if (strcmp(udev_device_get_subsystem(dev), "net") == 0 && strcmp(udev_device_get_action(dev), "add") == 0 && event->name != NULL && strcmp(event->name, udev_device_get_sysname(dev)) != 0) { char syspath[UTIL_PATH_SIZE]; char *pos; err = rename_netif(event); if (err == 0) { info(event->udev, "renamed netif to '%s'\n", event->name); /* delete stale db file */ udev_device_delete_db(dev); udev_device_tag_index(dev, NULL, false); /* remember old name */ udev_device_add_property(dev, "INTERFACE_OLD", udev_device_get_sysname(dev)); /* now change the devpath, because the kernel device name has changed */ util_strscpy(syspath, sizeof(syspath), udev_device_get_syspath(dev)); pos = strrchr(syspath, '/'); if (pos != NULL) { pos++; util_strscpy(pos, sizeof(syspath) - (pos - syspath), event->name); udev_device_set_syspath(event->dev, syspath); udev_device_add_property(dev, "INTERFACE", udev_device_get_sysname(dev)); info(event->udev, "changed devpath to '%s'\n", udev_device_get_devpath(dev)); } } } if (major(udev_device_get_devnum(dev)) != 0) { char filename[UTIL_PATH_SIZE]; if (event->tmp_node != NULL) { info(event->udev, "cleanup temporary device node\n"); util_unlink_secure(event->udev, event->tmp_node); free(event->tmp_node); event->tmp_node = NULL; } /* no rule, use kernel provided name */ if (event->name == NULL) { if (udev_device_get_knodename(dev) != NULL) { event->name = strdup(udev_device_get_knodename(dev)); info(event->udev, "no node name set, will use kernel supplied name '%s'\n", event->name); } else { event->name = strdup(udev_device_get_sysname(event->dev)); info(event->udev, "no node name set, will use device name '%s'\n", event->name); } } if (event->name == NULL || event->name[0] == '\0') { udev_device_delete_db(dev); udev_device_tag_index(dev, NULL, false); udev_device_unref(event->dev_db); err = -ENOMEM; err(event->udev, "no node name, something went wrong, ignoring\n"); goto out; } if (udev_device_get_knodename(dev) != NULL && strcmp(udev_device_get_knodename(dev), event->name) != 0) err(event->udev, "kernel-provided name '%s' and NAME= '%s' disagree, " "please use SYMLINK+= or change the kernel to provide the proper name\n", udev_device_get_knodename(dev), event->name); /* set device node name */ util_strscpyl(filename, sizeof(filename), udev_get_dev_path(event->udev), "/", event->name, NULL); udev_device_set_devnode(dev, filename); } udev_device_update_db(dev); udev_device_tag_index(dev, event->dev_db, true); if (major(udev_device_get_devnum(dev)) != 0) { /* remove/update possible left-over symlinks from old database entry */ if (event->dev_db != NULL) udev_node_update_old_links(dev, event->dev_db); /* change default 0600 to 0660 if a group is assigned */ if (event->mode == 0600 && event->gid > 0) event->mode = 0660; err = udev_node_add(dev, event->mode, event->uid, event->gid); } udev_device_unref(event->dev_db); event->dev_db = NULL; } out: return err; } int udev_event_execute_run(struct udev_event *event, const sigset_t *sigmask) { struct udev_list_entry *list_entry; int err = 0; dbg(event->udev, "executing run list\n"); udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) { const char *cmd = udev_list_entry_get_name(list_entry); if (strncmp(cmd, "socket:", strlen("socket:")) == 0) { struct udev_monitor *monitor; monitor = udev_monitor_new_from_socket(event->udev, &cmd[strlen("socket:")]); if (monitor == NULL) continue; udev_monitor_send_device(monitor, NULL, event->dev); udev_monitor_unref(monitor); } else { char program[UTIL_PATH_SIZE]; char **envp; udev_event_apply_format(event, cmd, program, sizeof(program)); envp = udev_device_get_properties_envp(event->dev); if (event->exec_delay > 0) { info(event->udev, "delay execution of '%s'\n", program); sleep(event->exec_delay); } if (util_run_program(event->udev, program, envp, NULL, 0, NULL, sigmask, true) != 0) { if (udev_list_entry_get_flags(list_entry)) err = -1; } } } return err; }