blob: d543accc10dd0be24a870ebaa634bd9c7cb199e7 [file] [log] [blame]
Steve Frenchf1d662a2007-11-05 14:38:08 +00001/*
2 * fs/cifs/cifs_spnego.c -- SPNEGO upcall management for CIFS
3 *
4 * Copyright (c) 2007 Red Hat, Inc.
5 * Author(s): Jeff Layton (jlayton@redhat.com)
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 * the GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22#include <linux/list.h>
23#include <linux/string.h>
24#include <keys/user-type.h>
25#include <linux/key-type.h>
26#include "cifsglob.h"
27#include "cifs_spnego.h"
28#include "cifs_debug.h"
29
30/* create a new cifs key */
31static int
32cifs_spnego_key_instantiate(struct key *key, const void *data, size_t datalen)
33{
34 char *payload;
35 int ret;
36
37 ret = -ENOMEM;
38 payload = kmalloc(datalen, GFP_KERNEL);
39 if (!payload)
40 goto error;
41
42 /* attach the data */
43 memcpy(payload, data, datalen);
44 rcu_assign_pointer(key->payload.data, payload);
45 ret = 0;
46
47error:
48 return ret;
49}
50
51static void
52cifs_spnego_key_destroy(struct key *key)
53{
54 kfree(key->payload.data);
55}
56
57
58/*
59 * keytype for CIFS spnego keys
60 */
61struct key_type cifs_spnego_key_type = {
62 .name = "cifs.spnego",
63 .instantiate = cifs_spnego_key_instantiate,
64 .match = user_match,
65 .destroy = cifs_spnego_key_destroy,
66 .describe = user_describe,
67};
68
Steve French68bf7282007-11-16 18:32:52 +000069#define MAX_VER_STR_LEN 9 /* length of longest version string e.g.
Steve Frenchf7a44ea2007-11-17 00:01:51 +000070 strlen(";ver=0xFF") */
Steve French68bf7282007-11-16 18:32:52 +000071#define MAX_MECH_STR_LEN 13 /* length of longest security mechanism name, eg
72 in future could have strlen(";sec=ntlmsspi") */
73#define MAX_IPV6_ADDR_LEN 42 /* eg FEDC:BA98:7654:3210:FEDC:BA98:7654:3210/60 */
Steve Frenchf1d662a2007-11-05 14:38:08 +000074/* get a key struct with a SPNEGO security blob, suitable for session setup */
75struct key *
Jeff Laytond6c2e4d2007-11-16 22:23:17 +000076cifs_get_spnego_key(struct cifsSesInfo *sesInfo)
Steve Frenchf1d662a2007-11-05 14:38:08 +000077{
78 struct TCP_Server_Info *server = sesInfo->server;
79 char *description, *dp;
80 size_t desc_len;
81 struct key *spnego_key;
Jeff Laytond6c2e4d2007-11-16 22:23:17 +000082 const char *hostname = server->hostname;
Steve Frenchf1d662a2007-11-05 14:38:08 +000083
Steve French68bf7282007-11-16 18:32:52 +000084 /* BB: come up with better scheme for determining length */
85 /* length of fields (with semicolons): ver=0xyz ipv4= ipaddress host=
86 hostname sec=mechanism uid=0x uid */
87 desc_len = MAX_VER_STR_LEN + 5 + MAX_IPV6_ADDR_LEN + 1 + 6 +
88 strlen(hostname) + MAX_MECH_STR_LEN + 8 + (sizeof(uid_t) * 2);
Steve Frenchf1d662a2007-11-05 14:38:08 +000089 spnego_key = ERR_PTR(-ENOMEM);
90 description = kzalloc(desc_len, GFP_KERNEL);
91 if (description == NULL)
92 goto out;
93
94 dp = description;
95 /* start with version and hostname portion of UNC string */
96 spnego_key = ERR_PTR(-EINVAL);
Steve French68bf7282007-11-16 18:32:52 +000097 sprintf(dp, "ver=0x%x;host=%s;", CIFS_SPNEGO_UPCALL_VERSION,
Steve Frenchf1d662a2007-11-05 14:38:08 +000098 hostname);
99 dp = description + strlen(description);
100
101 /* add the server address */
102 if (server->addr.sockAddr.sin_family == AF_INET)
103 sprintf(dp, "ip4=" NIPQUAD_FMT,
104 NIPQUAD(server->addr.sockAddr.sin_addr));
105 else if (server->addr.sockAddr.sin_family == AF_INET6)
106 sprintf(dp, "ip6=" NIP6_SEQFMT,
107 NIP6(server->addr.sockAddr6.sin6_addr));
108 else
109 goto out;
110
111 dp = description + strlen(description);
112
113 /* for now, only sec=krb5 is valid */
114 if (server->secType == Kerberos)
115 sprintf(dp, ";sec=krb5");
116 else
117 goto out;
118
Igor Mammedov9eae8a82007-11-08 16:13:31 +0000119 dp = description + strlen(description);
120 sprintf(dp, ";uid=0x%x", sesInfo->linux_uid);
121
Steve Frenchf1d662a2007-11-05 14:38:08 +0000122 cFYI(1, ("key description = %s", description));
123 spnego_key = request_key(&cifs_spnego_key_type, description, "");
124
Jeff Layton05b3de62007-12-31 00:51:45 +0000125#ifdef CONFIG_CIFS_DEBUG2
Steve Frenchf1d662a2007-11-05 14:38:08 +0000126 if (cifsFYI && !IS_ERR(spnego_key)) {
127 struct cifs_spnego_msg *msg = spnego_key->payload.data;
Jeff Layton05b3de62007-12-31 00:51:45 +0000128 cifs_dump_mem("SPNEGO reply blob:", msg->data, min(1024,
129 msg->secblob_len + msg->sesskey_len));
Steve Frenchf1d662a2007-11-05 14:38:08 +0000130 }
Jeff Layton05b3de62007-12-31 00:51:45 +0000131#endif /* CONFIG_CIFS_DEBUG2 */
Steve Frenchf1d662a2007-11-05 14:38:08 +0000132
133out:
134 kfree(description);
135 return spnego_key;
136}