/* * namedev.c * * Userspace devfs * * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com> * * * 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 <stddef.h> #include <stdlib.h> #include <string.h> #include <stdio.h> #include <fcntl.h> #include <ctype.h> #include <unistd.h> #include <errno.h> #include <sys/wait.h> #include <sys/stat.h> #include <sys/sysinfo.h> #include "libsysfs/sysfs/libsysfs.h" #include "list.h" #include "udev.h" #include "udev_lib.h" #include "udev_version.h" #include "logging.h" #include "namedev.h" #include "udevdb.h" static struct sysfs_attribute *find_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device, char *attr); LIST_HEAD(config_device_list); LIST_HEAD(perm_device_list); /* compare string with pattern (supports * ? [0-9] [!A-Z]) */ static int strcmp_pattern(const char *p, const char *s) { if (s[0] == '\0') { while (p[0] == '*') p++; return (p[0] != '\0'); } switch (p[0]) { case '[': { int not = 0; p++; if (p[0] == '!') { not = 1; p++; } while ((p[0] != '\0') && (p[0] != ']')) { int match = 0; if (p[1] == '-') { if ((s[0] >= p[0]) && (s[0] <= p[2])) match = 1; p += 3; } else { match = (p[0] == s[0]); p++; } if (match ^ not) { while ((p[0] != '\0') && (p[0] != ']')) p++; if (p[0] == ']') return strcmp_pattern(p+1, s+1); } } } break; case '*': if (strcmp_pattern(p, s+1)) return strcmp_pattern(p+1, s); return 0; case '\0': if (s[0] == '\0') { return 0; } break; default: if ((p[0] == s[0]) || (p[0] == '?')) return strcmp_pattern(p+1, s+1); break; } return 1; } static struct perm_device *find_perm(char *name) { struct perm_device *perm; list_for_each_entry(perm, &perm_device_list, node) { if (strcmp_pattern(perm->name, name)) continue; return perm; } return NULL; } static mode_t get_default_mode(void) { mode_t mode = 0600; /* default to owner rw only */ if (strlen(default_mode_str) != 0) mode = strtol(default_mode_str, NULL, 8); return mode; } static char *get_default_owner(void) { if (strlen(default_owner_str) == 0) strfieldcpy(default_owner_str, "root"); return default_owner_str; } static char *get_default_group(void) { if (strlen(default_group_str) == 0) strfieldcpy(default_group_str, "root"); return default_group_str; } /* extract possible {attr} and move str behind it */ static char *get_format_attribute(char **str) { char *pos; char *attr = NULL; if (*str[0] == '{') { pos = strchr(*str, '}'); if (pos == NULL) { dbg("missing closing brace for format"); return NULL; } pos[0] = '\0'; attr = *str+1; *str = pos+1; dbg("attribute='%s', str='%s'", attr, *str); } return attr; } /* extract possible format length and move str behind it*/ static int get_format_len(char **str) { int num; char *tail; if (isdigit(*str[0])) { num = (int) strtoul(*str, &tail, 10); if (num > 0) { *str = tail; dbg("format length=%i", num); return num; } else { dbg("format parsing error '%s'", *str); } } return -1; } /** Finds the lowest positive N such that <name>N isn't present in * $(udevroot) either as a file or a symlink. * * @param name Name to check for * @return 0 if <name> didn't exist and N otherwise. */ static int find_free_number(struct udevice *udev, const char *name) { char filename[NAME_SIZE]; int num = 0; struct udevice db_udev; strfieldcpy(filename, name); while (1) { dbg("look for existing node '%s'", filename); memset(&db_udev, 0x00, sizeof(struct udevice)); if (udevdb_get_dev_byname(&db_udev, filename) != 0) { dbg("free num=%d", num); return num; } num++; if (num > 1000) { info("find_free_number gone crazy (num=%d), aborted", num); return -1; } snprintf(filename, NAME_SIZE-1, "%s%d", name, num); filename[NAME_SIZE-1] = '\0'; } } static void apply_format(struct udevice *udev, char *string, size_t maxsize, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device) { char temp[NAME_SIZE]; char temp2[NAME_SIZE]; char *tail; char *pos; char *attr; int len; int i; char c; char *spos; char *rest; int slen; struct sysfs_attribute *tmpattr; unsigned int next_free_number; pos = string; while (1) { pos = strchr(pos, '%'); if (pos == NULL) break; pos[0] = '\0'; tail = pos+1; len = get_format_len(&tail); c = tail[0]; strfieldcpy(temp, tail+1); tail = temp; dbg("format=%c, string='%s', tail='%s'",c , string, tail); attr = get_format_attribute(&tail); switch (c) { case 'b': if (strlen(udev->bus_id) == 0) break; strfieldcatmax(string, udev->bus_id, maxsize); dbg("substitute bus_id '%s'", udev->bus_id); break; case 'k': if (strlen(udev->kernel_name) == 0) break; strfieldcatmax(string, udev->kernel_name, maxsize); dbg("substitute kernel name '%s'", udev->kernel_name); break; case 'n': if (strlen(udev->kernel_number) == 0) break; strfieldcatmax(string, udev->kernel_number, maxsize); dbg("substitute kernel number '%s'", udev->kernel_number); break; case 'm': strintcatmax(string, udev->minor, maxsize); dbg("substitute minor number '%u'", udev->minor); break; case 'M': strintcatmax(string, udev->major, maxsize); dbg("substitute major number '%u'", udev->major); break; case 'c': if (strlen(udev->program_result) == 0) break; /* get part part of the result string */ i = 0; if (attr != NULL) i = strtoul(attr, &rest, 10); if (i > 0) { foreach_strpart(udev->program_result, " \n\r", spos, slen) { i--; if (i == 0) break; } if (i > 0) { dbg("requested part of result string not found"); break; } if (rest[0] == '+') strfieldcpy(temp2, spos); else strfieldcpymax(temp2, spos, slen+1); strfieldcatmax(string, temp2, maxsize); dbg("substitute part of result string '%s'", temp2); } else { strfieldcatmax(string, udev->program_result, maxsize); dbg("substitute result string '%s'", udev->program_result); } break; case 's': if (attr != NULL) { tmpattr = find_sysfs_attribute(class_dev, sysfs_device, attr); if (tmpattr == NULL) { dbg("sysfa attribute '%s' not found", attr); break; } /* strip trailing whitespace of matching value */ if (isspace(tmpattr->value[strlen(tmpattr->value)-1])) { i = len = strlen(tmpattr->value); while (i > 0 && isspace(tmpattr->value[i-1])) i--; if (i < len) { tmpattr->value[i] = '\0'; dbg("remove %i trailing whitespace chars from '%s'", len - i, tmpattr->value); } } strfieldcatmax(string, tmpattr->value, maxsize); dbg("substitute sysfs value '%s'", tmpattr->value); } else { dbg("missing attribute"); } break; case '%': strfieldcatmax(string, "%", maxsize); pos++; break; case 'e': next_free_number = find_free_number(udev, string); if (next_free_number > 0) { sprintf(temp2, "%d", next_free_number); strfieldcatmax(string, temp2, maxsize); } break; default: dbg("unknown substitution type '%%%c'", c); break; } /* truncate to specified length */ if (len > 0) pos[len] = '\0'; strfieldcatmax(string, tail, maxsize); } } static void fix_kernel_name(struct udevice *udev) { char *temp = udev->kernel_name; while (*temp != 0x00) { /* Some block devices have a ! in their name, * we need to change that to / */ if (*temp == '!') *temp = '/'; ++temp; } } static int execute_program(const char *path, char *value, int len) { int retval; int count; int status; int fds[2]; pid_t pid; char *pos; char arg[PROGRAM_SIZE]; char *argv[(PROGRAM_SIZE / 2) + 1]; int i; strfieldcpy(arg, path); i = 0; if (strchr(path, ' ')) { pos = arg; while (pos != NULL) { if (pos[0] == '\'') { /* don't separate if in apostrophes */ pos++; argv[i] = strsep(&pos, "\'"); while (pos && pos[0] == ' ') pos++; } else { argv[i] = strsep(&pos, " "); } dbg("arg[%i] '%s'", i, argv[i]); i++; } argv[i] = NULL; dbg("execute '%s' with parsed arguments", arg); } else { argv[0] = arg; argv[1] = main_argv[1]; argv[2] = NULL; dbg("execute '%s' with subsystem '%s' argument", arg, argv[1]); } retval = pipe(fds); if (retval != 0) { dbg("pipe failed"); return -1; } pid = fork(); switch(pid) { case 0: /* child */ /* dup2 write side of pipe to STDOUT */ dup2(fds[1], STDOUT_FILENO); retval = execv(arg, argv); info(FIELD_PROGRAM " execution of '%s' failed", path); exit(1); case -1: dbg("fork failed"); return -1; default: /* parent reads from fds[0] */ close(fds[1]); retval = 0; i = 0; while (1) { count = read(fds[0], value + i, len - i-1); if (count <= 0) break; i += count; if (i >= len-1) { dbg("result len %d too short", len); retval = -1; break; } } if (count < 0) { dbg("read failed with '%s'", strerror(errno)); retval = -1; } if (i > 0 && value[i-1] == '\n') i--; value[i] = '\0'; dbg("result is '%s'", value); close(fds[0]); waitpid(pid, &status, 0); if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0)) { dbg("exec program status 0x%x", status); retval = -1; } } return retval; } static struct sysfs_attribute *find_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device, char *attr) { struct sysfs_attribute *tmpattr = NULL; char *c; dbg("look for device attribute '%s'", attr); /* try to find the attribute in the class device directory */ tmpattr = sysfs_get_classdev_attr(class_dev, attr); if (tmpattr) goto attr_found; /* look in the class device directory if present */ if (sysfs_device) { tmpattr = sysfs_get_device_attr(sysfs_device, attr); if (tmpattr) goto attr_found; } return NULL; attr_found: c = strchr(tmpattr->value, '\n'); if (c != NULL) c[0] = '\0'; dbg("found attribute '%s'", tmpattr->path); return tmpattr; } static int compare_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device, struct sysfs_pair *pair) { struct sysfs_attribute *tmpattr; int i; int len; if ((pair == NULL) || (pair->file[0] == '\0') || (pair->value == '\0')) return -ENODEV; tmpattr = find_sysfs_attribute(class_dev, sysfs_device, pair->file); if (tmpattr == NULL) return -ENODEV; /* strip trailing whitespace of value, if not asked to match for it */ if (! isspace(pair->value[strlen(pair->value)-1])) { i = len = strlen(tmpattr->value); while (i > 0 && isspace(tmpattr->value[i-1])) i--; if (i < len) { tmpattr->value[i] = '\0'; dbg("remove %i trailing whitespace chars from '%s'", len - i, tmpattr->value); } } dbg("compare attribute '%s' value '%s' with '%s'", pair->file, tmpattr->value, pair->value); if (strcmp_pattern(pair->value, tmpattr->value) != 0) return -ENODEV; dbg("found matching attribute '%s' with value '%s'", pair->file, pair->value); return 0; } static int match_sysfs_pairs(struct config_device *dev, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device) { struct sysfs_pair *pair; int i; for (i = 0; i < MAX_SYSFS_PAIRS; ++i) { pair = &dev->sysfs_pair[i]; if ((pair->file[0] == '\0') || (pair->value[0] == '\0')) break; if (compare_sysfs_attribute(class_dev, sysfs_device, pair) != 0) { dbg("sysfs attribute doesn't match"); return -ENODEV; } } return 0; } static int match_id(struct config_device *dev, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device) { char path[SYSFS_PATH_MAX]; char *temp = NULL; /* we have to have a sysfs device for ID to work */ if (!sysfs_device) return -ENODEV; strfieldcpy(path, sysfs_device->path); temp = strrchr(path, '/'); temp++; dbg("search '%s' in '%s', path='%s'", dev->id, temp, path); if (strcmp_pattern(dev->id, temp) != 0) return -ENODEV; else return 0; } static int match_place(struct config_device *dev, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device) { char path[SYSFS_PATH_MAX]; int found; char *temp = NULL; /* we have to have a sysfs device for PLACE to work */ if (!sysfs_device) return -ENODEV; found = 0; strfieldcpy(path, sysfs_device->path); temp = strrchr(path, '/'); dbg("search '%s' in '%s', path='%s'", dev->place, temp, path); if (strstr(temp, dev->place) != NULL) { found = 1; } else { *temp = 0x00; temp = strrchr(path, '/'); dbg("search '%s' in '%s', path='%s'", dev->place, temp, path); if (strstr(temp, dev->place) != NULL) found = 1; } if (!found) { dbg("place doesn't match"); return -ENODEV; } return 0; } static int match_rule(struct config_device *dev, struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device) { while (1) { /* check for matching bus value */ if (dev->bus[0] != '\0') { if (sysfs_device == NULL) { dbg("device has no bus"); goto try_parent; } dbg("check for " FIELD_BUS " dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus); if (strcmp_pattern(dev->bus, sysfs_device->bus) != 0) { dbg(FIELD_BUS " is not matching"); goto try_parent; } else { dbg(FIELD_BUS " matches"); } } /* check for matching kernel name*/ if (dev->kernel[0] != '\0') { dbg("check for " FIELD_KERNEL " dev->kernel='%s' class_dev->name='%s'", dev->kernel, class_dev->name); if (strcmp_pattern(dev->kernel, class_dev->name) != 0) { dbg(FIELD_KERNEL " is not matching"); goto try_parent; } else { dbg(FIELD_KERNEL " matches"); } } /* check for matching bus id */ if (dev->id[0] != '\0') { dbg("check " FIELD_ID); if (match_id(dev, class_dev, sysfs_device) != 0) { dbg(FIELD_ID " is not matching"); goto try_parent; } else { dbg(FIELD_ID " matches"); } } /* check for matching place of device */ if (dev->place[0] != '\0') { dbg("check " FIELD_PLACE); if (match_place(dev, class_dev, sysfs_device) != 0) { dbg(FIELD_PLACE " is not matching"); goto try_parent; } else { dbg(FIELD_PLACE " matches"); } } /* check for matching sysfs pairs */ if (dev->sysfs_pair[0].file[0] != '\0') { dbg("check " FIELD_SYSFS " pairs"); if (match_sysfs_pairs(dev, class_dev, sysfs_device) != 0) { dbg(FIELD_SYSFS " is not matching"); goto try_parent; } else { dbg(FIELD_SYSFS " matches"); } } /* execute external program */ if (dev->program[0] != '\0') { char program[PROGRAM_SIZE]; dbg("check " FIELD_PROGRAM); strfieldcpy(program, dev->program); apply_format(udev, program, sizeof(program), class_dev, sysfs_device); if (execute_program(program, udev->program_result, NAME_SIZE) != 0) { dbg(FIELD_PROGRAM " returned nonzero"); goto try_parent; } else { dbg(FIELD_PROGRAM " returned successful"); } } /* check for matching result of external program */ if (dev->result[0] != '\0') { dbg("check for " FIELD_RESULT " dev->result='%s', udev->program_result='%s'", dev->result, udev->program_result); if (strcmp_pattern(dev->result, udev->program_result) != 0) { dbg(FIELD_RESULT " is not matching"); goto try_parent; } else { dbg(FIELD_RESULT " matches"); } } /* Yeah, we matched! */ return 0; try_parent: dbg("try parent sysfs device"); sysfs_device = sysfs_get_device_parent(sysfs_device); if (sysfs_device == NULL) return -ENODEV; dbg("sysfs_device->path='%s'", sysfs_device->path); dbg("sysfs_device->bus_id='%s'", sysfs_device->bus_id); dbg("sysfs_device->bus='%s'", sysfs_device->bus); } } int namedev_name_device(struct udevice *udev, struct sysfs_class_device *class_dev) { struct sysfs_class_device *class_dev_parent; struct sysfs_device *sysfs_device = NULL; struct config_device *dev; struct perm_device *perm; struct sysinfo info; char *pos; udev->mode = 0; dbg("class_dev->name='%s'", class_dev->name); /* Figure out where the "device"-symlink is at. For char devices this will * always be in the class_dev->path. On block devices, only the main block * device will have the device symlink in it's path. All partition devices * need to look at the symlink in its parent directory. */ class_dev_parent = sysfs_get_classdev_parent(class_dev); if (class_dev_parent != NULL) { dbg("given class device has a parent, use this instead"); sysfs_device = sysfs_get_classdev_device(class_dev_parent); } else { sysfs_device = sysfs_get_classdev_device(class_dev); } if (sysfs_device) { dbg("found devices device: path='%s', bus_id='%s', bus='%s'", sysfs_device->path, sysfs_device->bus_id, sysfs_device->bus); strfieldcpy(udev->bus_id, sysfs_device->bus_id); strfieldcpy(udev->bus, sysfs_device->bus); } strfieldcpy(udev->kernel_name, class_dev->name); fix_kernel_name(udev); dbg("udev->kernel_name = '%s'", udev->kernel_name); /* get kernel number */ pos = class_dev->name + strlen(class_dev->name); while (isdigit(*(pos-1))) pos--; strfieldcpy(udev->kernel_number, pos); dbg("kernel_number='%s'", udev->kernel_number); /* look for a matching rule to apply */ list_for_each_entry(dev, &config_device_list, node) { dbg("process rule"); if (match_rule(dev, class_dev, udev, sysfs_device) == 0) { if (dev->name[0] == '\0' && dev->symlink[0] == '\0') { info("configured rule in '%s' at line %i applied, '%s' is ignored", dev->config_file, dev->config_line, udev->kernel_name); return -1; } if (dev->symlink[0] != '\0') { char temp[NAME_SIZE]; info("configured rule in '%s' at line %i applied, added symlink '%s'", dev->config_file, dev->config_line, dev->symlink); strfieldcpy(temp, dev->symlink); apply_format(udev, temp, sizeof(temp), class_dev, sysfs_device); if (udev->symlink[0] != '\0') strfieldcat(udev->symlink, " "); strfieldcat(udev->symlink, temp); } if (dev->name[0] != '\0') { /* apply all_partitions flag only at a main block device */ if (dev->partitions > 0 && (udev->type != 'b' || udev->kernel_number[0] != '\0')) continue; info("configured rule in '%s' at line %i applied, '%s' becomes '%s'", dev->config_file, dev->config_line, udev->kernel_name, dev->name); strfieldcpy(udev->name, dev->name); goto found; } } } /* no rule was found so we use the kernel name */ strfieldcpy(udev->name, udev->kernel_name); if (udev->type == 'n') goto done; else goto perms; found: apply_format(udev, udev->name, sizeof(udev->name), class_dev, sysfs_device); strfieldcpy(udev->config_file, dev->config_file); udev->config_line = dev->config_line; if (udev->type == 'n') goto done; udev->partitions = dev->partitions; /* get permissions given in rule */ set_empty_perms(udev, dev->mode, dev->owner, dev->group); perms: /* get permissions given in config file or set defaults */ perm = find_perm(udev->name); if (perm != NULL) { set_empty_perms(udev, perm->mode, perm->owner, perm->group); } set_empty_perms(udev, get_default_mode(), get_default_owner(), get_default_group()); dbg("name, '%s' is going to have owner='%s', group='%s', mode = %#o", udev->name, udev->owner, udev->group, udev->mode); done: /* store time of action */ sysinfo(&info); udev->config_uptime = info.uptime; return 0; } int namedev_init(void) { int retval; retval = namedev_init_rules(); if (retval) return retval; retval = namedev_init_permissions(); if (retval) return retval; dump_config_dev_list(); dump_perm_dev_list(); return retval; }