summaryrefslogtreecommitdiffstats
path: root/sftp-usergroup.c
blob: 93396ffc63dbf0a58bcd59446b4d078004adbd96 (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
/*
 * Copyright (c) 2022 Damien Miller <djm@mindrot.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/* sftp client user/group lookup and caching */

#include "includes.h"

#include <sys/types.h>
#include <openbsd-compat/sys-tree.h>

#include <stdlib.h>
#include <stdarg.h>
#include <string.h>

#include "log.h"
#include "xmalloc.h"

#include "sftp-common.h"
#include "sftp-client.h"
#include "sftp-usergroup.h"

/* Tree of id, name */
struct idname {
        u_int id;
	char *name;
        RB_ENTRY(idname) entry;
	/* XXX implement bounded cache as TAILQ */
};
static int
idname_cmp(struct idname *a, struct idname *b)
{
	if (a->id == b->id)
		return 0;
	return a->id > b->id ? 1 : -1;
}
RB_HEAD(idname_tree, idname);
RB_GENERATE_STATIC(idname_tree, idname, entry, idname_cmp)

static struct idname_tree user_idname = RB_INITIALIZER(&user_idname);
static struct idname_tree group_idname = RB_INITIALIZER(&group_idname);

static void
idname_free(struct idname *idname)
{
	if (idname == NULL)
		return;
	free(idname->name);
	free(idname);
}

static void
idname_enter(struct idname_tree *tree, u_int id, const char *name)
{
	struct idname *idname;

	if ((idname = xcalloc(1, sizeof(*idname))) == NULL)
		fatal_f("alloc");
	idname->id = id;
	idname->name = xstrdup(name);
	if (RB_INSERT(idname_tree, tree, idname) != NULL)
		idname_free(idname);
}

static const char *
idname_lookup(struct idname_tree *tree, u_int id)
{
	struct idname idname, *found;

	memset(&idname, 0, sizeof(idname));
	idname.id = id;
	if ((found = RB_FIND(idname_tree, tree, &idname)) != NULL)
		return found->name;
	return NULL;
}

static void
freenames(char **names, u_int nnames)
{
	u_int i;

	if (names == NULL)
		return;
	for (i = 0; i < nnames; i++)
		free(names[i]);
	free(names);
}

static void
lookup_and_record(struct sftp_conn *conn,
    u_int *uids, u_int nuids, u_int *gids, u_int ngids)
{
	int r;
	u_int i;
	char **usernames = NULL, **groupnames = NULL;

	if ((r = sftp_get_users_groups_by_id(conn, uids, nuids, gids, ngids,
	    &usernames, &groupnames)) != 0) {
		debug_fr(r, "sftp_get_users_groups_by_id");
		return;
	}
	for (i = 0; i < nuids; i++) {
		if (usernames[i] == NULL) {
			debug3_f("uid %u not resolved", uids[i]);
			continue;
		}
		debug3_f("record uid %u => \"%s\"", uids[i], usernames[i]);
		idname_enter(&user_idname, uids[i], usernames[i]);
	}
	for (i = 0; i < ngids; i++) {
		if (groupnames[i] == NULL) {
			debug3_f("gid %u not resolved", gids[i]);
			continue;
		}
		debug3_f("record gid %u => \"%s\"", gids[i], groupnames[i]);
		idname_enter(&group_idname, gids[i], groupnames[i]);
	}
	freenames(usernames, nuids);
	freenames(groupnames, ngids);
}

static int
has_id(u_int id, u_int *ids, u_int nids)
{
	u_int i;

	if (nids == 0)
		return 0;

	/* XXX O(N^2) */
	for (i = 0; i < nids; i++) {
		if (ids[i] == id)
			break;
	}
	return i < nids;
}

static void
collect_ids_from_glob(glob_t *g, int user, u_int **idsp, u_int *nidsp)
{
	u_int id, i, n = 0, *ids = NULL;

	for (i = 0; g->gl_pathv[i] != NULL; i++) {
		if (user) {
			if (ruser_name(g->gl_statv[i]->st_uid) != NULL)
				continue; /* Already seen */
			id = (u_int)g->gl_statv[i]->st_uid;
		} else {
			if (rgroup_name(g->gl_statv[i]->st_gid) != NULL)
				continue; /* Already seen */
			id = (u_int)g->gl_statv[i]->st_gid;
		}
		if (has_id(id, ids, n))
			continue;
		ids = xrecallocarray(ids, n, n + 1, sizeof(*ids));
		ids[n++] = id;
	}
	*idsp = ids;
	*nidsp = n;
}

void
get_remote_user_groups_from_glob(struct sftp_conn *conn, glob_t *g)
{
	u_int *uids = NULL, nuids = 0, *gids = NULL, ngids = 0;

	if (!sftp_can_get_users_groups_by_id(conn))
		return;

	collect_ids_from_glob(g, 1, &uids, &nuids);
	collect_ids_from_glob(g, 0, &gids, &ngids);
	lookup_and_record(conn, uids, nuids, gids, ngids);
	free(uids);
	free(gids);
}

static void
collect_ids_from_dirents(SFTP_DIRENT **d, int user, u_int **idsp, u_int *nidsp)
{
	u_int id, i, n = 0, *ids = NULL;

	for (i = 0; d[i] != NULL; i++) {
		if (user) {
			if (ruser_name((uid_t)(d[i]->a.uid)) != NULL)
				continue; /* Already seen */
			id = d[i]->a.uid;
		} else {
			if (rgroup_name((gid_t)(d[i]->a.gid)) != NULL)
				continue; /* Already seen */
			id = d[i]->a.gid;
		}
		if (has_id(id, ids, n))
			continue;
		ids = xrecallocarray(ids, n, n + 1, sizeof(*ids));
		ids[n++] = id;
	}
	*idsp = ids;
	*nidsp = n;
}

void
get_remote_user_groups_from_dirents(struct sftp_conn *conn, SFTP_DIRENT **d)
{
	u_int *uids = NULL, nuids = 0, *gids = NULL, ngids = 0;

	if (!sftp_can_get_users_groups_by_id(conn))
		return;

	collect_ids_from_dirents(d, 1, &uids, &nuids);
	collect_ids_from_dirents(d, 0, &gids, &ngids);
	lookup_and_record(conn, uids, nuids, gids, ngids);
	free(uids);
	free(gids);
}

const char *
ruser_name(uid_t uid)
{
	return idname_lookup(&user_idname, (u_int)uid);
}

const char *
rgroup_name(uid_t gid)
{
	return idname_lookup(&group_idname, (u_int)gid);
}