[thirdparty/systemd.git] / src / udev / libudev-util-private.c

/*
 * libudev - interface to udev device information
 *
 * Copyright (C) 2003-2009 Kay Sievers <kay.sievers@vrfy.org>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 */

#include <stdlib.h>
#include <stdio.h>
#include <stddef.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#include <pwd.h>
#include <grp.h>
#include <sys/param.h>

#include "libudev.h"
#include "libudev-private.h"

static int create_path(struct udev *udev, const char *path, bool selinux)
{
        char p[UTIL_PATH_SIZE];
        char *pos;
        struct stat stats;
        int err;

        util_strscpy(p, sizeof(p), path);
        pos = strrchr(p, '/');
        if (pos == NULL)
                return 0;
        while (pos != p && pos[-1] == '/')
                pos--;
        if (pos == p)
                return 0;
        pos[0] = '\0';

        if (stat(p, &stats) == 0) {
                if ((stats.st_mode & S_IFMT) == S_IFDIR)
                        return 0;
                else
                        return -ENOTDIR;
        }

        err = util_create_path(udev, p);
        if (err != 0)
                return err;

        if (selinux)
                udev_selinux_setfscreatecon(udev, p, S_IFDIR|0755);
        err = mkdir(p, 0755);
        if (err != 0) {
                err = -errno;
                if (err == -EEXIST && stat(p, &stats) == 0) {
                        if ((stats.st_mode & S_IFMT) == S_IFDIR)
                                err = 0;
                        else
                                err = -ENOTDIR;
                }
        }
        if (selinux)
                udev_selinux_resetfscreatecon(udev);
        return err;
}

int util_create_path(struct udev *udev, const char *path)
{
        return create_path(udev, path, false);
}

int util_create_path_selinux(struct udev *udev, const char *path)
{
        return create_path(udev, path, true);
}

int util_delete_path(struct udev *udev, const char *path)
{
        char p[UTIL_PATH_SIZE];
        char *pos;
        int err = 0;

        if (path[0] == '/')
                while(path[1] == '/')
                        path++;
        util_strscpy(p, sizeof(p), path);
        pos = strrchr(p, '/');
        if (pos == p || pos == NULL)
                return 0;

        for (;;) {
                *pos = '\0';
                pos = strrchr(p, '/');

                /* don't remove the last one */
                if ((pos == p) || (pos == NULL))
                        break;

                err = rmdir(p);
                if (err < 0) {
                        if (errno == ENOENT)
                                err = 0;
                        break;
                }
        }
        return err;
}

uid_t util_lookup_user(struct udev *udev, const char *user)
{
        char *endptr;
        struct passwd pwbuf;
        struct passwd *pw;
        uid_t uid;
        size_t buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
        char *buf = alloca(buflen);

        if (strcmp(user, "root") == 0)
                return 0;
        uid = strtoul(user, &endptr, 10);
        if (endptr[0] == '\0')
                return uid;

        errno = getpwnam_r(user, &pwbuf, buf, buflen, &pw);
        if (pw != NULL)
                return pw->pw_uid;
        if (errno == 0 || errno == ENOENT || errno == ESRCH)
                err(udev, "specified user '%s' unknown\n", user);
        else
                err(udev, "error resolving user '%s': %m\n", user);
        return 0;
}

gid_t util_lookup_group(struct udev *udev, const char *group)
{
        char *endptr;
        struct group grbuf;
        struct group *gr;
        gid_t gid = 0;
        size_t buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
        char *buf = alloca(buflen);

        if (strcmp(group, "root") == 0)
                return 0;
        gid = strtoul(group, &endptr, 10);
        if (endptr[0] == '\0')
                return gid;
        buf = NULL;
        gid = 0;
        for (;;) {
                char *newbuf;

                newbuf = realloc(buf, buflen);
                if (!newbuf)
                        break;
                buf = newbuf;
                errno = getgrnam_r(group, &grbuf, buf, buflen, &gr);
                if (gr != NULL) {
                        gid = gr->gr_gid;
                } else if (errno == ERANGE) {
                        buflen *= 2;
                        continue;
                } else if (errno == 0 || errno == ENOENT || errno == ESRCH) {
                        err(udev, "specified group '%s' unknown\n", group);
                } else {
                        err(udev, "error resolving group '%s': %m\n", group);
                }
                break;
        }
        free(buf);
        return gid;
}

/* handle "[<SUBSYSTEM>/<KERNEL>]<attribute>" format */
int util_resolve_subsys_kernel(struct udev *udev, const char *string,
                               char *result, size_t maxsize, int read_value)
{
        char temp[UTIL_PATH_SIZE];
        char *subsys;
        char *sysname;
        struct udev_device *dev;
        char *attr;

        if (string[0] != '[')
                return -1;

        util_strscpy(temp, sizeof(temp), string);

        subsys = &temp[1];

        sysname = strchr(subsys, '/');
        if (sysname == NULL)
                return -1;
        sysname[0] = '\0';
        sysname = &sysname[1];

        attr = strchr(sysname, ']');
        if (attr == NULL)
                return -1;
        attr[0] = '\0';
        attr = &attr[1];
        if (attr[0] == '/')
                attr = &attr[1];
        if (attr[0] == '\0')
                attr = NULL;

        if (read_value && attr == NULL)
                return -1;

        dev = udev_device_new_from_subsystem_sysname(udev, subsys, sysname);
        if (dev == NULL)
                return -1;

        if (read_value) {
                const char *val;

                val = udev_device_get_sysattr_value(dev, attr);
                if (val != NULL)
                        util_strscpy(result, maxsize, val);
                else
                        result[0] = '\0';
                dbg(udev, "value '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
        } else {
                size_t l;
                char *s;

                s = result;
                l = util_strpcpyl(&s, maxsize, udev_device_get_syspath(dev), NULL);
                if (attr != NULL)
                        util_strpcpyl(&s, l, "/", attr, NULL);
                dbg(udev, "path '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
        }
        udev_device_unref(dev);
        return 0;
}
Commit	Line	Data
c81b35c0	1	/*
44b49d37	2	* libudev - interface to udev device information
c81b35c0	3	*
fc206fbe	4	* Copyright (C) 2003-2009 Kay Sievers <kay.sievers@vrfy.org>
c81b35c0	5	*
44b49d37 KS	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.
c81b35c0 KS	10	*/
c81b35c0 KS	11
c81b35c0 KS	12	#include <stdlib.h>
c81b35c0 KS	13	#include <stdio.h>
4a539daf	14	#include <stddef.h>
c81b35c0	15	#include <unistd.h>
01618658	16	#include <string.h>
c81b35c0	17	#include <fcntl.h>
4a539daf	18	#include <errno.h>
9f8dfa19	19	#include <ctype.h>
3a020a85 KS	20	#include <pwd.h>
3a020a85 KS	21	#include <grp.h>
257bb4cd	22	#include <sys/param.h>
c81b35c0	23
44b49d37 KS	24	#include "libudev.h"
44b49d37 KS	25	#include "libudev-private.h"
c81b35c0	26
51f43b53	27	static int create_path(struct udev udev, const char path, bool selinux)
4a539daf	28	{
912541b0 KS	29	char p[UTIL_PATH_SIZE];
	30	char *pos;
	31	struct stat stats;
	32	int err;
	33
	34	util_strscpy(p, sizeof(p), path);
	35	pos = strrchr(p, '/');
	36	if (pos == NULL)
	37	return 0;
	38	while (pos != p && pos[-1] == '/')
	39	pos--;
	40	if (pos == p)
	41	return 0;
	42	pos[0] = '\0';
	43
912541b0 KS	44	if (stat(p, &stats) == 0) {
	45	if ((stats.st_mode & S_IFMT) == S_IFDIR)
	46	return 0;
	47	else
	48	return -ENOTDIR;
	49	}
	50
	51	err = util_create_path(udev, p);
	52	if (err != 0)
	53	return err;
	54
912541b0 KS	55	if (selinux)
	56	udev_selinux_setfscreatecon(udev, p, S_IFDIR\|0755);
	57	err = mkdir(p, 0755);
	58	if (err != 0) {
	59	err = -errno;
	60	if (err == -EEXIST && stat(p, &stats) == 0) {
	61	if ((stats.st_mode & S_IFMT) == S_IFDIR)
	62	err = 0;
	63	else
	64	err = -ENOTDIR;
	65	}
	66	}
	67	if (selinux)
	68	udev_selinux_resetfscreatecon(udev);
	69	return err;
a390e6f7	70	}
4a539daf	71
51f43b53 KS	72	int util_create_path(struct udev udev, const char path)
51f43b53 KS	73	{
912541b0	74	return create_path(udev, path, false);
51f43b53 KS	75	}
	76
	77	int util_create_path_selinux(struct udev udev, const char path)
	78	{
912541b0	79	return create_path(udev, path, true);
51f43b53 KS	80	}
51f43b53 KS	81
54808d77	82	int util_delete_path(struct udev udev, const char path)
a390e6f7	83	{
912541b0 KS	84	char p[UTIL_PATH_SIZE];
	85	char *pos;
	86	int err = 0;
	87
	88	if (path[0] == '/')
	89	while(path[1] == '/')
	90	path++;
	91	util_strscpy(p, sizeof(p), path);
	92	pos = strrchr(p, '/');
	93	if (pos == p \|\| pos == NULL)
	94	return 0;
	95
	96	for (;;) {
	97	*pos = '\0';
	98	pos = strrchr(p, '/');
	99
	100	/* don't remove the last one */
	101	if ((pos == p) \|\| (pos == NULL))
	102	break;
	103
	104	err = rmdir(p);
	105	if (err < 0) {
	106	if (errno == ENOENT)
	107	err = 0;
	108	break;
	109	}
	110	}
	111	return err;
b8476286 KS	112	}
b8476286 KS	113
54808d77	114	uid_t util_lookup_user(struct udev udev, const char user)
3a020a85	115	{
912541b0	116	char *endptr;
912541b0 KS	117	struct passwd pwbuf;
	118	struct passwd *pw;
	119	uid_t uid;
fc863dea KS	120	size_t buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
fc863dea KS	121	char *buf = alloca(buflen);
912541b0 KS	122
	123	if (strcmp(user, "root") == 0)
	124	return 0;
	125	uid = strtoul(user, &endptr, 10);
	126	if (endptr[0] == '\0')
	127	return uid;
	128
	129	errno = getpwnam_r(user, &pwbuf, buf, buflen, &pw);
	130	if (pw != NULL)
	131	return pw->pw_uid;
	132	if (errno == 0 \|\| errno == ENOENT \|\| errno == ESRCH)
	133	err(udev, "specified user '%s' unknown\n", user);
	134	else
	135	err(udev, "error resolving user '%s': %m\n", user);
	136	return 0;
90024521	137	}
3a020a85	138
37ed4f56	139	gid_t util_lookup_group(struct udev udev, const char group)
90024521	140	{
912541b0	141	char *endptr;
912541b0 KS	142	struct group grbuf;
	143	struct group *gr;
	144	gid_t gid = 0;
fc863dea KS	145	size_t buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
fc863dea KS	146	char *buf = alloca(buflen);
912541b0 KS	147
	148	if (strcmp(group, "root") == 0)
	149	return 0;
	150	gid = strtoul(group, &endptr, 10);
	151	if (endptr[0] == '\0')
	152	return gid;
	153	buf = NULL;
	154	gid = 0;
	155	for (;;) {
	156	char *newbuf;
	157
	158	newbuf = realloc(buf, buflen);
	159	if (!newbuf)
	160	break;
	161	buf = newbuf;
	162	errno = getgrnam_r(group, &grbuf, buf, buflen, &gr);
	163	if (gr != NULL) {
	164	gid = gr->gr_gid;
	165	} else if (errno == ERANGE) {
	166	buflen *= 2;
	167	continue;
	168	} else if (errno == 0 \|\| errno == ENOENT \|\| errno == ESRCH) {
	169	err(udev, "specified group '%s' unknown\n", group);
	170	} else {
	171	err(udev, "error resolving group '%s': %m\n", group);
	172	}
	173	break;
	174	}
	175	free(buf);
	176	return gid;
90024521	177	}
d0db192f	178
14f40256 KS	179	/* handle "[<SUBSYSTEM>/<KERNEL>]<attribute>" format */
14f40256 KS	180	int util_resolve_subsys_kernel(struct udev udev, const char string,
912541b0	181	char *result, size_t maxsize, int read_value)
14f40256	182	{
912541b0 KS	183	char temp[UTIL_PATH_SIZE];
	184	char *subsys;
	185	char *sysname;
	186	struct udev_device *dev;
	187	char *attr;
	188
	189	if (string[0] != '[')
	190	return -1;
	191
	192	util_strscpy(temp, sizeof(temp), string);
	193
	194	subsys = &temp[1];
	195
	196	sysname = strchr(subsys, '/');
	197	if (sysname == NULL)
	198	return -1;
	199	sysname[0] = '\0';
	200	sysname = &sysname[1];
	201
	202	attr = strchr(sysname, ']');
	203	if (attr == NULL)
	204	return -1;
	205	attr[0] = '\0';
	206	attr = &attr[1];
	207	if (attr[0] == '/')
	208	attr = &attr[1];
	209	if (attr[0] == '\0')
	210	attr = NULL;
	211
	212	if (read_value && attr == NULL)
	213	return -1;
	214
	215	dev = udev_device_new_from_subsystem_sysname(udev, subsys, sysname);
	216	if (dev == NULL)
	217	return -1;
	218
	219	if (read_value) {
	220	const char *val;
	221
	222	val = udev_device_get_sysattr_value(dev, attr);
	223	if (val != NULL)
	224	util_strscpy(result, maxsize, val);
	225	else
	226	result[0] = '\0';
baa30fbc	227	dbg(udev, "value '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
912541b0 KS	228	} else {
	229	size_t l;
	230	char *s;
	231
	232	s = result;
	233	l = util_strpcpyl(&s, maxsize, udev_device_get_syspath(dev), NULL);
	234	if (attr != NULL)
	235	util_strpcpyl(&s, l, "/", attr, NULL);
baa30fbc	236	dbg(udev, "path '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
912541b0 KS	237	}
	238	udev_device_unref(dev);
	239	return 0;
14f40256	240	}