summaryrefslogtreecommitdiff
path: root/src/basic/mkdir.c
blob: 41af1482bc7bfbf0d139bcc4c913df485d6389ef (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include <errno.h>
#include <stdbool.h>
#include <string.h>

#include "alloc-util.h"
#include "chase.h"
#include "fd-util.h"
#include "format-util.h"
#include "fs-util.h"
#include "macro.h"
#include "mkdir.h"
#include "path-util.h"
#include "stat-util.h"
#include "stdio-util.h"
#include "user-util.h"

int mkdirat_safe_internal(
                int dir_fd,
                const char *path,
                mode_t mode,
                uid_t uid,
                gid_t gid,
                MkdirFlags flags,
                mkdirat_func_t _mkdirat) {

        struct stat st;
        int r;

        assert(path);
        assert(mode != MODE_INVALID);
        assert(_mkdirat && _mkdirat != mkdirat);

        r = _mkdirat(dir_fd, path, mode);
        if (r >= 0)
                return chmod_and_chown_at(dir_fd, path, mode, uid, gid);
        if (r != -EEXIST)
                return r;

        if (fstatat(dir_fd, path, &st, AT_SYMLINK_NOFOLLOW) < 0)
                return -errno;

        if ((flags & MKDIR_FOLLOW_SYMLINK) && S_ISLNK(st.st_mode)) {
                _cleanup_free_ char *p = NULL;

                r = chaseat(dir_fd, path, CHASE_NONEXISTENT, &p, NULL);
                if (r < 0)
                        return r;
                if (r == 0)
                        return mkdirat_safe_internal(dir_fd, p, mode, uid, gid,
                                                     flags & ~MKDIR_FOLLOW_SYMLINK,
                                                     _mkdirat);

                if (fstatat(dir_fd, p, &st, AT_SYMLINK_NOFOLLOW) < 0)
                        return -errno;
        }

        if (flags & MKDIR_IGNORE_EXISTING)
                return 0;

        if (!S_ISDIR(st.st_mode))
                return log_full_errno(flags & MKDIR_WARN_MODE ? LOG_WARNING : LOG_DEBUG, SYNTHETIC_ERRNO(ENOTDIR),
                                      "Path \"%s\" already exists and is not a directory, refusing.", path);

        if ((st.st_mode & ~mode & 0777) != 0)
                return log_full_errno(flags & MKDIR_WARN_MODE ? LOG_WARNING : LOG_DEBUG, SYNTHETIC_ERRNO(EEXIST),
                                      "Directory \"%s\" already exists, but has mode %04o that is too permissive (%04o was requested), refusing.",
                                      path, st.st_mode & 0777, mode);

        if ((uid != UID_INVALID && st.st_uid != uid) ||
            (gid != GID_INVALID && st.st_gid != gid)) {
                char u[DECIMAL_STR_MAX(uid_t)] = "-", g[DECIMAL_STR_MAX(gid_t)] = "-";

                if (uid != UID_INVALID)
                        xsprintf(u, UID_FMT, uid);
                if (gid != UID_INVALID)
                        xsprintf(g, GID_FMT, gid);
                return log_full_errno(flags & MKDIR_WARN_MODE ? LOG_WARNING : LOG_DEBUG, SYNTHETIC_ERRNO(EEXIST),
                                      "Directory \"%s\" already exists, but is owned by "UID_FMT":"GID_FMT" (%s:%s was requested), refusing.",
                                      path, st.st_uid, st.st_gid, u, g);
        }

        return 0;
}

int mkdirat_errno_wrapper(int dirfd, const char *pathname, mode_t mode) {
        return RET_NERRNO(mkdirat(dirfd, pathname, mode));
}

int mkdirat_safe(int dir_fd, const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags) {
        return mkdirat_safe_internal(dir_fd, path, mode, uid, gid, flags, mkdirat_errno_wrapper);
}

int mkdirat_parents_internal(int dir_fd, const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags, mkdirat_func_t _mkdirat) {
        const char *e = NULL;
        int r;

        assert(path);
        assert(_mkdirat != mkdirat);

        if (isempty(path))
                return 0;

        if (!path_is_safe(path))
                return -ENOTDIR;

        /* return immediately if directory exists */
        r = path_find_last_component(path, /* accept_dot_dot= */ false, &e, NULL);
        if (r <= 0) /* r == 0 means path is equivalent to prefix. */
                return r;
        if (e == path)
                return 0;

        assert(e > path);
        assert(*e == '/');

        /* drop the last component */
        path = strndupa_safe(path, e - path);
        r = is_dir_full(dir_fd, path, true);
        if (r > 0)
                return 0;
        if (r == 0)
                return -ENOTDIR;

        /* create every parent directory in the path, except the last component */
        for (const char *p = path;;) {
                char *s;
                int n;

                n = path_find_first_component(&p, /* accept_dot_dot= */ false, (const char **) &s);
                if (n <= 0)
                        return n;

                assert(p);
                assert(s >= path);
                assert(IN_SET(s[n], '/', '\0'));

                s[n] = '\0';

                r = mkdirat_safe_internal(dir_fd, path, mode, uid, gid, flags | MKDIR_IGNORE_EXISTING, _mkdirat);
                if (r < 0 && r != -EEXIST)
                        return r;

                s[n] = *p == '\0' ? '\0' : '/';
        }
}

int mkdir_parents_internal(const char *prefix, const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags, mkdirat_func_t _mkdirat) {
        _cleanup_close_ int fd = AT_FDCWD;
        const char *p;

        assert(path);
        assert(_mkdirat != mkdirat);

        if (prefix) {
                p = path_startswith_full(path, prefix, /* accept_dot_dot= */ false);
                if (!p)
                        return -ENOTDIR;
        } else
                p = path;

        if (prefix) {
                fd = open(prefix, O_PATH|O_DIRECTORY|O_CLOEXEC);
                if (fd < 0)
                        return -errno;
        }

        return mkdirat_parents_internal(fd, p, mode, uid, gid, flags, _mkdirat);
}

int mkdirat_parents(int dir_fd, const char *path, mode_t mode) {
        return mkdirat_parents_internal(dir_fd, path, mode, UID_INVALID, UID_INVALID, 0, mkdirat_errno_wrapper);
}

int mkdir_parents_safe(const char *prefix, const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags) {
        return mkdir_parents_internal(prefix, path, mode, uid, gid, flags, mkdirat_errno_wrapper);
}

int mkdir_p_internal(const char *prefix, const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags, mkdirat_func_t _mkdirat) {
        int r;

        /* Like mkdir -p */

        assert(_mkdirat != mkdirat);

        r = mkdir_parents_internal(prefix, path, mode, uid, gid, flags | MKDIR_FOLLOW_SYMLINK, _mkdirat);
        if (r < 0)
                return r;

        if (!uid_is_valid(uid) && !gid_is_valid(gid) && flags == 0) {
                r = _mkdirat(AT_FDCWD, path, mode);
                if (r < 0 && (r != -EEXIST || is_dir(path, true) <= 0))
                        return r;
        } else {
                r = mkdir_safe_internal(path, mode, uid, gid, flags, _mkdirat);
                if (r < 0 && r != -EEXIST)
                        return r;
        }

        return 0;
}

int mkdir_p(const char *path, mode_t mode) {
        return mkdir_p_internal(NULL, path, mode, UID_INVALID, UID_INVALID, 0, mkdirat_errno_wrapper);
}

int mkdir_p_safe(const char *prefix, const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags) {
        return mkdir_p_internal(prefix, path, mode, uid, gid, flags, mkdirat_errno_wrapper);
}

int mkdir_p_root(const char *root, const char *p, uid_t uid, gid_t gid, mode_t m) {
        _cleanup_free_ char *pp = NULL, *bn = NULL;
        _cleanup_close_ int dfd = -EBADF;
        int r;

        r = path_extract_directory(p, &pp);
        if (r == -EDESTADDRREQ) {
                /* only fname is passed, no prefix to operate on */
                dfd = open(".", O_RDONLY|O_CLOEXEC|O_DIRECTORY);
                if (dfd < 0)
                        return -errno;
        } else if (r == -EADDRNOTAVAIL)
                /* only root dir or "." was passed, i.e. there is no parent to extract, in that case there's nothing to do. */
                return 0;
        else if (r < 0)
                return r;
        else {
                /* Extracting the parent dir worked, hence we aren't top-level? Recurse up first. */
                r = mkdir_p_root(root, pp, uid, gid, m);
                if (r < 0)
                        return r;

                dfd = chase_and_open(pp, root, CHASE_PREFIX_ROOT, O_RDONLY|O_CLOEXEC|O_DIRECTORY, NULL);
                if (dfd < 0)
                        return dfd;
        }

        r = path_extract_filename(p, &bn);
        if (r == -EADDRNOTAVAIL) /* Already top-level */
                return 0;
        if (r < 0)
                return r;

        if (mkdirat(dfd, bn, m) < 0) {
                if (errno == EEXIST)
                        return 0;

                return -errno;
        }

        if (uid_is_valid(uid) || gid_is_valid(gid)) {
                _cleanup_close_ int nfd = -EBADF;

                nfd = openat(dfd, bn, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOFOLLOW);
                if (nfd < 0)
                        return -errno;

                if (fchown(nfd, uid, gid) < 0)
                        return -errno;
        }

        return 1;
}