1.\"	$NetBSD: krb5_encrypt.3,v 1.1.1.3 2014/04/24 12:45:50 pettai Exp $
2.\"
3.\" Copyright (c) 1999 - 2004 Kungliga Tekniska Högskolan
4.\" (Royal Institute of Technology, Stockholm, Sweden).
5.\" All rights reserved.
6.\"
7.\" Redistribution and use in source and binary forms, with or without
8.\" modification, are permitted provided that the following conditions
9.\" are met:
10.\"
11.\" 1. Redistributions of source code must retain the above copyright
12.\"    notice, this list of conditions and the following disclaimer.
13.\"
14.\" 2. Redistributions in binary form must reproduce the above copyright
15.\"    notice, this list of conditions and the following disclaimer in the
16.\"    documentation and/or other materials provided with the distribution.
17.\"
18.\" 3. Neither the name of the Institute nor the names of its contributors
19.\"    may be used to endorse or promote products derived from this software
20.\"    without specific prior written permission.
21.\"
22.\" THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32.\" SUCH DAMAGE.
33.\"
34.\" Id
35.\"
36.Dd March 20, 2004
37.Dt KRB5_ENCRYPT 3
38.Os
39.Sh NAME
40.Nm krb5_crypto_getblocksize ,
41.Nm krb5_crypto_getconfoundersize
42.Nm krb5_crypto_getenctype ,
43.Nm krb5_crypto_getpadsize ,
44.Nm krb5_crypto_overhead ,
45.Nm krb5_decrypt ,
46.Nm krb5_decrypt_EncryptedData ,
47.Nm krb5_decrypt_ivec ,
48.Nm krb5_decrypt_ticket ,
49.Nm krb5_encrypt ,
50.Nm krb5_encrypt_EncryptedData ,
51.Nm krb5_encrypt_ivec ,
52.Nm krb5_enctype_disable ,
53.Nm krb5_enctype_keysize ,
54.Nm krb5_enctype_to_string ,
55.Nm krb5_enctype_valid ,
56.Nm krb5_get_wrapped_length ,
57.Nm krb5_string_to_enctype
58.Nd "encrypt and decrypt data, set and get encryption type parameters"
59.Sh LIBRARY
60Kerberos 5 Library (libkrb5, -lkrb5)
61.Sh SYNOPSIS
62.In krb5/krb5.h
63.Ft krb5_error_code
64.Fo krb5_encrypt
65.Fa "krb5_context context"
66.Fa "krb5_crypto crypto"
67.Fa "unsigned usage"
68.Fa "void *data"
69.Fa "size_t len"
70.Fa "krb5_data *result"
71.Fc
72.Ft krb5_error_code
73.Fo krb5_encrypt_EncryptedData
74.Fa "krb5_context context"
75.Fa "krb5_crypto crypto"
76.Fa "unsigned usage"
77.Fa "void *data"
78.Fa "size_t len"
79.Fa "int kvno"
80.Fa "EncryptedData *result"
81.Fc
82.Ft krb5_error_code
83.Fo krb5_encrypt_ivec
84.Fa "krb5_context context"
85.Fa "krb5_crypto crypto"
86.Fa "unsigned usage"
87.Fa "void *data"
88.Fa "size_t len"
89.Fa "krb5_data *result"
90.Fa "void *ivec"
91.Fc
92.Ft krb5_error_code
93.Fo krb5_decrypt
94.Fa "krb5_context context"
95.Fa "krb5_crypto crypto"
96.Fa "unsigned usage"
97.Fa "void *data"
98.Fa "size_t len"
99.Fa "krb5_data *result"
100.Fc
101.Ft krb5_error_code
102.Fo krb5_decrypt_EncryptedData
103.Fa "krb5_context context"
104.Fa "krb5_crypto crypto"
105.Fa "unsigned usage"
106.Fa "EncryptedData *e"
107.Fa "krb5_data *result"
108.Fc
109.Ft krb5_error_code
110.Fo krb5_decrypt_ivec
111.Fa "krb5_context context"
112.Fa "krb5_crypto crypto"
113.Fa "unsigned usage"
114.Fa "void *data"
115.Fa "size_t len"
116.Fa "krb5_data *result"
117.Fa "void *ivec"
118.Fc
119.Ft krb5_error_code
120.Fo krb5_decrypt_ticket
121.Fa "krb5_context context"
122.Fa "Ticket *ticket"
123.Fa "krb5_keyblock *key"
124.Fa "EncTicketPart *out"
125.Fa "krb5_flags flags"
126.Fc
127.Ft krb5_error_code
128.Fo krb5_crypto_getblocksize
129.Fa "krb5_context context"
130.Fa "size_t *blocksize"
131.Fc
132.Ft krb5_error_code
133.Fo krb5_crypto_getenctype
134.Fa "krb5_context context"
135.Fa "krb5_crypto crypto"
136.Fa "krb5_enctype *enctype"
137.Fc
138.Ft krb5_error_code
139.Fo krb5_crypto_getpadsize
140.Fa "krb5_context context"
141.Fa size_t *padsize"
142.Fc
143.Ft krb5_error_code
144.Fo krb5_crypto_getconfoundersize
145.Fa "krb5_context context"
146.Fa "krb5_crypto crypto"
147.Fa size_t *confoundersize"
148.Fc
149.Ft krb5_error_code
150.Fo krb5_enctype_keysize
151.Fa "krb5_context context"
152.Fa "krb5_enctype type"
153.Fa "size_t *keysize"
154.Fc
155.Ft krb5_error_code
156.Fo krb5_crypto_overhead
157.Fa "krb5_context context"
158.Fa size_t *padsize"
159.Fc
160.Ft krb5_error_code
161.Fo krb5_string_to_enctype
162.Fa "krb5_context context"
163.Fa "const char *string"
164.Fa "krb5_enctype *etype"
165.Fc
166.Ft krb5_error_code
167.Fo krb5_enctype_to_string
168.Fa "krb5_context context"
169.Fa "krb5_enctype etype"
170.Fa "char **string"
171.Fc
172.Ft krb5_error_code
173.Fo krb5_enctype_valid
174.Fa "krb5_context context"
175.Fa "krb5_enctype etype"
176.Fc
177.Ft void
178.Fo krb5_enctype_disable
179.Fa "krb5_context context"
180.Fa "krb5_enctype etype"
181.Fc
182.Ft size_t
183.Fo krb5_get_wrapped_length
184.Fa "krb5_context context"
185.Fa "krb5_crypto crypto"
186.Fa "size_t data_len"
187.Fc
188.Sh DESCRIPTION
189These functions are used to encrypt and decrypt data.
190.Pp
191.Fn krb5_encrypt_ivec
192puts the encrypted version of
193.Fa data
194(of size
195.Fa len )
196in
197.Fa result .
198If the encryption type supports using derived keys,
199.Fa usage
200should be the appropriate key-usage.
201.Fa ivec
202is a pointer to a initial IV, it is modified to the end IV at the end of
203the round.
204Ivec should be the size of
205If
206.Dv NULL
207is passed in, the default IV is used.
208.Fn krb5_encrypt
209does the same as
210.Fn krb5_encrypt_ivec
211but with
212.Fa ivec
213being
214.Dv NULL .
215.Fn krb5_encrypt_EncryptedData
216does the same as
217.Fn krb5_encrypt ,
218but it puts the encrypted data in a
219.Fa EncryptedData
220structure instead. If
221.Fa kvno
222is not zero, it will be put in the (optional)
223.Fa kvno
224field in the
225.Fa EncryptedData .
226.Pp
227.Fn krb5_decrypt_ivec ,
228.Fn krb5_decrypt ,
229and
230.Fn krb5_decrypt_EncryptedData
231works similarly.
232.Pp
233.Fn krb5_decrypt_ticket
234decrypts the encrypted part of
235.Fa ticket
236with
237.Fa key .
238.Fn krb5_decrypt_ticket
239also verifies the timestamp in the ticket, invalid flag and if the KDC
240haven't verified the transited path, the transit path.
241.Pp
242.Fn krb5_enctype_keysize ,
243.Fn krb5_crypto_getconfoundersize ,
244.Fn krb5_crypto_getblocksize ,
245.Fn krb5_crypto_getenctype ,
246.Fn krb5_crypto_getpadsize ,
247.Fn krb5_crypto_overhead
248all returns various (sometimes) useful information from a crypto context.
249.Fn krb5_crypto_overhead
250is the combination of krb5_crypto_getconfoundersize,
251krb5_crypto_getblocksize and krb5_crypto_getpadsize and return the
252maximum overhead size.
253.Pp
254.Fn krb5_enctype_to_string
255converts a encryption type number to a string that can be printable
256and stored. The strings returned should be freed with
257.Xr free 3 .
258.Pp
259.Fn krb5_string_to_enctype
260converts a encryption type strings to a encryption type number that
261can use used for other Kerberos crypto functions.
262.Pp
263.Fn krb5_enctype_valid
264returns 0 if the encrypt is supported and not disabled, otherwise and
265error code is returned.
266.Pp
267.Fn krb5_enctype_disable
268(globally, for all contextes) disables the
269.Fa enctype .
270.Pp
271.Fn krb5_get_wrapped_length
272returns the size of an encrypted packet by
273.Fa crypto
274of length
275.Fa data_len .
276.\" .Sh EXAMPLE
277.\" .Sh BUGS
278.Sh SEE ALSO
279.Xr krb5_create_checksum 3 ,
280.Xr krb5_crypto_init 3
281