summaryrefslogtreecommitdiff
path: root/auth/gensec/gensec_util.c
blob: 64952b198374ef66d09ff084661c7dbd3d8551a4 (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
/*
   Unix SMB/CIFS implementation.

   Generic Authentication Interface

   Copyright (C) Andrew Tridgell 2003
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2006

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "auth/gensec/gensec.h"
#include "auth/common_auth.h"
#include "../lib/util/asn1.h"

NTSTATUS gensec_generate_session_info_pac(TALLOC_CTX *mem_ctx,
					  struct gensec_security *gensec_security,
					  struct smb_krb5_context *smb_krb5_context,
					  DATA_BLOB *pac_blob,
					  const char *principal_string,
					  const struct tsocket_address *remote_address,
					  struct auth_session_info **session_info)
{
	uint32_t session_info_flags = 0;

	if (gensec_security->want_features & GENSEC_FEATURE_UNIX_TOKEN) {
		session_info_flags |= AUTH_SESSION_INFO_UNIX_TOKEN;
	}

	session_info_flags |= AUTH_SESSION_INFO_DEFAULT_GROUPS;

	if (!pac_blob) {
		if (gensec_setting_bool(gensec_security->settings, "gensec", "require_pac", false)) {
			DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access\n",
				  principal_string));
			return NT_STATUS_ACCESS_DENIED;
		}
		DEBUG(1, ("Unable to find PAC for %s, resorting to local user lookup\n",
			  principal_string));
	}

	if (gensec_security->auth_context && gensec_security->auth_context->generate_session_info_pac) {
		return gensec_security->auth_context->generate_session_info_pac(gensec_security->auth_context,
										mem_ctx,
										smb_krb5_context,
										pac_blob,
										principal_string,
										remote_address,
										session_info_flags,
										session_info);
	} else {
		DEBUG(0, ("Cannot generate a session_info without the auth_context\n"));
		return NT_STATUS_INTERNAL_ERROR;
	}
}

/*
 * These functions are for use in the deprecated
 * gensec_socket code (public because SPNEGO must
 * use them for recursion)
 */
_PUBLIC_ NTSTATUS gensec_wrap_packets(struct gensec_security *gensec_security,
			     TALLOC_CTX *mem_ctx,
			     const DATA_BLOB *in,
			     DATA_BLOB *out,
			     size_t *len_processed)
{
	if (!gensec_security->ops->wrap_packets) {
		NTSTATUS nt_status;
		size_t max_input_size;
		DATA_BLOB unwrapped, wrapped;
		max_input_size = gensec_max_input_size(gensec_security);
		unwrapped = data_blob_const(in->data, MIN(max_input_size, (size_t)in->length));

		nt_status = gensec_wrap(gensec_security,
					mem_ctx,
					&unwrapped, &wrapped);
		if (!NT_STATUS_IS_OK(nt_status)) {
			return nt_status;
		}

		*out = data_blob_talloc(mem_ctx, NULL, 4);
		if (!out->data) {
			return NT_STATUS_NO_MEMORY;
		}
		RSIVAL(out->data, 0, wrapped.length);

		if (!data_blob_append(mem_ctx, out, wrapped.data, wrapped.length)) {
			return NT_STATUS_NO_MEMORY;
		}
		*len_processed = unwrapped.length;
		return NT_STATUS_OK;
	}
	return gensec_security->ops->wrap_packets(gensec_security, mem_ctx, in, out,
						  len_processed);
}

/*
 * These functions are for use in the deprecated
 * gensec_socket code (public because SPNEGO must
 * use them for recursion)
 */
NTSTATUS gensec_unwrap_packets(struct gensec_security *gensec_security,
					TALLOC_CTX *mem_ctx,
					const DATA_BLOB *in,
					DATA_BLOB *out,
					size_t *len_processed)
{
	if (!gensec_security->ops->unwrap_packets) {
		DATA_BLOB wrapped;
		NTSTATUS nt_status;
		size_t packet_size;
		if (in->length < 4) {
			/* Missing the header we already had! */
			DEBUG(0, ("Asked to unwrap packet of bogus length!  How did we get the short packet?!\n"));
			return NT_STATUS_INVALID_PARAMETER;
		}

		packet_size = RIVAL(in->data, 0);

		wrapped = data_blob_const(in->data + 4, packet_size);

		if (wrapped.length > (in->length - 4)) {
			DEBUG(0, ("Asked to unwrap packed of bogus length %d > %d!  How did we get this?!\n",
				  (int)wrapped.length, (int)(in->length - 4)));
			return NT_STATUS_INTERNAL_ERROR;
		}

		nt_status = gensec_unwrap(gensec_security,
					  mem_ctx,
					  &wrapped, out);
		if (!NT_STATUS_IS_OK(nt_status)) {
			return nt_status;
		}

		*len_processed = packet_size + 4;
		return nt_status;
	}
	return gensec_security->ops->unwrap_packets(gensec_security, mem_ctx, in, out,
						    len_processed);
}

/*
 * These functions are for use in the deprecated
 * gensec_socket code (public because SPNEGO must
 * use them for recursion)
 */
NTSTATUS gensec_packet_full_request(struct gensec_security *gensec_security,
				    DATA_BLOB blob, size_t *size)
{
	if (gensec_security->ops->packet_full_request) {
		return gensec_security->ops->packet_full_request(gensec_security,
								 blob, size);
	}
	if (gensec_security->ops->unwrap_packets) {
		if (blob.length) {
			*size = blob.length;
			return NT_STATUS_OK;
		}
		return STATUS_MORE_ENTRIES;
	}

	if (blob.length < 4) {
		return STATUS_MORE_ENTRIES;
	}
	*size = 4 + RIVAL(blob.data, 0);
	if (*size > blob.length) {
		return STATUS_MORE_ENTRIES;
	}
	return NT_STATUS_OK;
}

/*
  magic check a GSS-API wrapper packet for an Kerberos OID
*/
static bool gensec_gssapi_check_oid(const DATA_BLOB *blob, const char *oid)
{
	bool ret;
	struct asn1_data *data = asn1_init(NULL);

	if (!data) return false;

	asn1_load(data, *blob);
	asn1_start_tag(data, ASN1_APPLICATION(0));
	asn1_check_OID(data, oid);

	ret = !data->has_error;

	asn1_free(data);

	return ret;
}

/**
 * Check if the packet is one for the KRB5 mechansim
 *
 * NOTE: This is a helper that can be employed by multiple mechanisms, do
 * not make assumptions about the private_data
 *
 * @param gensec_security GENSEC state, unused
 * @param in The request, as a DATA_BLOB
 * @return Error, INVALID_PARAMETER if it's not a packet for us
 *                or NT_STATUS_OK if the packet is ok.
 */

NTSTATUS gensec_magic_check_krb5_oid(struct gensec_security *unused,
					const DATA_BLOB *blob)
{
	if (gensec_gssapi_check_oid(blob, GENSEC_OID_KERBEROS5)) {
		return NT_STATUS_OK;
	} else {
		return NT_STATUS_INVALID_PARAMETER;
	}
}