summaryrefslogtreecommitdiffstats
path: root/net/sunrpc/auth_gss/gss_krb5_mech.c
blob: 70e1e53a632b1120ca8913fbec39a67a97455ae4 (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
/*
 *  linux/net/sunrpc/gss_krb5_mech.c
 *
 *  Copyright (c) 2001 The Regents of the University of Michigan.
 *  All rights reserved.
 *
 *  Andy Adamson <andros@umich.edu>
 *  J. Bruce Fields <bfields@umich.edu>
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. Neither the name of the University nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/sunrpc/auth.h>
#include <linux/sunrpc/gss_krb5.h>
#include <linux/sunrpc/xdr.h>
#include <linux/crypto.h>

#ifdef RPC_DEBUG
# define RPCDBG_FACILITY	RPCDBG_AUTH
#endif

static const void *
simple_get_bytes(const void *p, const void *end, void *res, int len)
{
	const void *q = (const void *)((const char *)p + len);
	if (unlikely(q > end || q < p))
		return ERR_PTR(-EFAULT);
	memcpy(res, p, len);
	return q;
}

static const void *
simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
{
	const void *q;
	unsigned int len;

	p = simple_get_bytes(p, end, &len, sizeof(len));
	if (IS_ERR(p))
		return p;
	q = (const void *)((const char *)p + len);
	if (unlikely(q > end || q < p))
		return ERR_PTR(-EFAULT);
	res->data = kmalloc(len, GFP_KERNEL);
	if (unlikely(res->data == NULL))
		return ERR_PTR(-ENOMEM);
	memcpy(res->data, p, len);
	res->len = len;
	return q;
}

static inline const void *
get_key(const void *p, const void *end, struct crypto_tfm **res)
{
	struct xdr_netobj	key;
	int			alg, alg_mode;
	char			*alg_name;

	p = simple_get_bytes(p, end, &alg, sizeof(alg));
	if (IS_ERR(p))
		goto out_err;
	p = simple_get_netobj(p, end, &key);
	if (IS_ERR(p))
		goto out_err;

	switch (alg) {
		case ENCTYPE_DES_CBC_RAW:
			alg_name = "des";
			alg_mode = CRYPTO_TFM_MODE_CBC;
			break;
		default:
			printk("gss_kerberos_mech: unsupported algorithm %d\n", alg);
			goto out_err_free_key;
	}
	if (!(*res = crypto_alloc_tfm(alg_name, alg_mode))) {
		printk("gss_kerberos_mech: unable to initialize crypto algorithm %s\n", alg_name);
		goto out_err_free_key;
	}
	if (crypto_cipher_setkey(*res, key.data, key.len)) {
		printk("gss_kerberos_mech: error setting key for crypto algorithm %s\n", alg_name);
		goto out_err_free_tfm;
	}

	kfree(key.data);
	return p;

out_err_free_tfm:
	crypto_free_tfm(*res);
out_err_free_key:
	kfree(key.data);
	p = ERR_PTR(-EINVAL);
out_err:
	return p;
}

static int
gss_import_sec_context_kerberos(const void *p,
				size_t len,
				struct gss_ctx *ctx_id)
{
	const void *end = (const void *)((const char *)p + len);
	struct	krb5_ctx *ctx;

	if (!(ctx = kzalloc(sizeof(*ctx), GFP_KERNEL)))
		goto out_err;

	p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
	if (IS_ERR(p))
		goto out_err_free_ctx;
	p = simple_get_bytes(p, end, &ctx->seed_init, sizeof(ctx->seed_init));
	if (IS_ERR(p))
		goto out_err_free_ctx;
	p = simple_get_bytes(p, end, ctx->seed, sizeof(ctx->seed));
	if (IS_ERR(p))
		goto out_err_free_ctx;
	p = simple_get_bytes(p, end, &ctx->signalg, sizeof(ctx->signalg));
	if (IS_ERR(p))
		goto out_err_free_ctx;
	p = simple_get_bytes(p, end, &ctx->sealalg, sizeof(ctx->sealalg));
	if (IS_ERR(p))
		goto out_err_free_ctx;
	p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
	if (IS_ERR(p))
		goto out_err_free_ctx;
	p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
	if (IS_ERR(p))
		goto out_err_free_ctx;
	p = simple_get_netobj(p, end, &ctx->mech_used);
	if (IS_ERR(p))
		goto out_err_free_ctx;
	p = get_key(p, end, &ctx->enc);
	if (IS_ERR(p))
		goto out_err_free_mech;
	p = get_key(p, end, &ctx->seq);
	if (IS_ERR(p))
		goto out_err_free_key1;
	if (p != end) {
		p = ERR_PTR(-EFAULT);
		goto out_err_free_key2;
	}

	ctx_id->internal_ctx_id = ctx;
	dprintk("RPC:      Successfully imported new context.\n");
	return 0;

out_err_free_key2:
	crypto_free_tfm(ctx->seq);
out_err_free_key1:
	crypto_free_tfm(ctx->enc);
out_err_free_mech:
	kfree(ctx->mech_used.data);
out_err_free_ctx:
	kfree(ctx);
out_err:
	return PTR_ERR(p);
}

static void
gss_delete_sec_context_kerberos(void *internal_ctx) {
	struct krb5_ctx *kctx = internal_ctx;

	crypto_free_tfm(kctx->seq);
	crypto_free_tfm(kctx->enc);
	kfree(kctx->mech_used.data);
	kfree(kctx);
}

static struct gss_api_ops gss_kerberos_ops = {
	.gss_import_sec_context	= gss_import_sec_context_kerberos,
	.gss_get_mic		= gss_get_mic_kerberos,
	.gss_verify_mic		= gss_verify_mic_kerberos,
	.gss_wrap		= gss_wrap_kerberos,
	.gss_unwrap		= gss_unwrap_kerberos,
	.gss_delete_sec_context	= gss_delete_sec_context_kerberos,
};

static struct pf_desc gss_kerberos_pfs[] = {
	[0] = {
		.pseudoflavor = RPC_AUTH_GSS_KRB5,
		.service = RPC_GSS_SVC_NONE,
		.name = "krb5",
	},
	[1] = {
		.pseudoflavor = RPC_AUTH_GSS_KRB5I,
		.service = RPC_GSS_SVC_INTEGRITY,
		.name = "krb5i",
	},
	[2] = {
		.pseudoflavor = RPC_AUTH_GSS_KRB5P,
		.service = RPC_GSS_SVC_PRIVACY,
		.name = "krb5p",
	},
};

static struct gss_api_mech gss_kerberos_mech = {
	.gm_name	= "krb5",
	.gm_owner	= THIS_MODULE,
	.gm_ops		= &gss_kerberos_ops,
	.gm_pf_num	= ARRAY_SIZE(gss_kerberos_pfs),
	.gm_pfs		= gss_kerberos_pfs,
};

static int __init init_kerberos_module(void)
{
	int status;

	status = gss_mech_register(&gss_kerberos_mech);
	if (status)
		printk("Failed to register kerberos gss mechanism!\n");
	return status;
}

static void __exit cleanup_kerberos_module(void)
{
	gss_mech_unregister(&gss_kerberos_mech);
}

MODULE_LICENSE("GPL");
module_init(init_kerberos_module);
module_exit(cleanup_kerberos_module);