1 #pragma ident	"%Z%%M%	%I%	%E% SMI"
2 /*
3  * lib/krb5/krb/ser_key.c
4  *
5  * Copyright 1995 by the Massachusetts Institute of Technology.
6  * All Rights Reserved.
7  *
8  * Export of this software from the United States of America may
9  *   require a specific license from the United States Government.
10  *   It is the responsibility of any person or organization contemplating
11  *   export to obtain such a license before exporting.
12  *
13  * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
14  * distribute this software and its documentation for any purpose and
15  * without fee is hereby granted, provided that the above copyright
16  * notice appear in all copies and that both that copyright notice and
17  * this permission notice appear in supporting documentation, and that
18  * the name of M.I.T. not be used in advertising or publicity pertaining
19  * to distribution of the software without specific, written prior
20  * permission.  M.I.T. makes no representations about the suitability of
21  * this software for any purpose.  It is provided "as is" without express
22  * or implied warranty.
23  *
24  */
25 
26 /*
27  * ser_key.c - Serialize a krb5_keyblock structure.
28  */
29 #include <k5-int.h>
30 #include <int-proto.h>
31 
32 /*
33  * Routines to deal with externalizing the krb5_keyblock:
34  *	krb5_keyblock_size();
35  *	krb5_keyblock_externalize();
36  *	krb5_keyblock_internalize();
37  */
38 static krb5_error_code krb5_keyblock_size
39 	(krb5_context, krb5_pointer, size_t *);
40 static krb5_error_code krb5_keyblock_externalize
41 	(krb5_context, krb5_pointer, krb5_octet **, size_t *);
42 static krb5_error_code krb5_keyblock_internalize
43 	(krb5_context,krb5_pointer *, krb5_octet **, size_t *);
44 
45 /* Local data */
46 static const krb5_ser_entry krb5_keyblock_ser_entry = {
47     KV5M_KEYBLOCK,			/* Type			*/
48     krb5_keyblock_size,			/* Sizer routine	*/
49     krb5_keyblock_externalize,		/* Externalize routine	*/
50     krb5_keyblock_internalize		/* Internalize routine	*/
51 };
52 
53 /*
54  * krb5_keyblock_size()	- Determine the size required to externalize
55  *				  the krb5_keyblock.
56  */
57 /*ARGSUSED*/
58 static krb5_error_code
59 krb5_keyblock_size(krb5_context kcontext, krb5_pointer arg, size_t *sizep)
60 {
61     krb5_error_code	kret;
62     krb5_keyblock	*keyblock;
63 
64     /*
65      * krb5_keyblock requires:
66      *	krb5_int32			for KV5M_KEYBLOCK
67      *	krb5_int32			for enctype
68      *	krb5_int32			for length
69      *	keyblock->length		for contents
70      *	krb5_int32			for KV5M_KEYBLOCK
71      */
72     kret = EINVAL;
73     keyblock = (krb5_keyblock *) arg;
74     if (keyblock) {
75 	*sizep += (sizeof(krb5_int32) +
76 		   sizeof(krb5_int32) +
77 		   sizeof(krb5_int32) +
78 		   sizeof(krb5_int32) +
79 		   sizeof(krb5_int32) +
80 		   (size_t) keyblock->length);
81 	kret = 0;
82     }
83     return(kret);
84 }
85 
86 /*
87  * krb5_keyblock_externalize()	- Externalize the krb5_keyblock.
88  */
89 static krb5_error_code
90 krb5_keyblock_externalize(krb5_context kcontext, krb5_pointer arg, krb5_octet **buffer, size_t *lenremain)
91 {
92     krb5_error_code	kret;
93     krb5_keyblock	*keyblock;
94     size_t		required;
95     krb5_octet		*bp;
96     size_t		remain;
97 
98     required = 0;
99     bp = *buffer;
100     remain = *lenremain;
101     kret = EINVAL;
102     keyblock = (krb5_keyblock *) arg;
103     if (keyblock) {
104 	kret = ENOMEM;
105 	if (!krb5_keyblock_size(kcontext, arg, &required) &&
106 	    (required <= remain)) {
107 	    /* Our identifier */
108 	    (void) krb5_ser_pack_int32(KV5M_KEYBLOCK, &bp, &remain);
109 
110 	    /* Our enctype */
111 	    (void) krb5_ser_pack_int32((krb5_int32) keyblock->enctype,
112 				       &bp, &remain);
113 
114 	    /* Our length */
115 	    (void) krb5_ser_pack_int32((krb5_int32) keyblock->length,
116 				       &bp, &remain);
117 
118 	    /* Our contents */
119 	    (void) krb5_ser_pack_bytes(keyblock->contents,
120 				       (size_t) keyblock->length,
121 				       &bp, &remain);
122 
123 	    /* Finally, our trailer */
124 	    (void) krb5_ser_pack_int32(KV5M_KEYBLOCK, &bp, &remain);
125 
126 	    kret = 0;
127 	    *buffer = bp;
128 	    *lenremain = remain;
129 	}
130     }
131     return(kret);
132 }
133 
134 /*
135  * krb5_keyblock_internalize()	- Internalize the krb5_keyblock.
136  */
137 
138 /*ARGSUSED*/
139 static krb5_error_code
140 krb5_keyblock_internalize(krb5_context kcontext, krb5_pointer *argp, krb5_octet **buffer, size_t *lenremain)
141 {
142     krb5_error_code	kret;
143     krb5_keyblock	*keyblock;
144     krb5_int32		ibuf;
145     krb5_octet		*bp;
146     size_t		remain;
147 
148     bp = *buffer;
149     remain = *lenremain;
150     kret = EINVAL;
151     /* Read our magic number */
152     if (krb5_ser_unpack_int32(&ibuf, &bp, &remain))
153 	ibuf = 0;
154     if (ibuf == KV5M_KEYBLOCK) {
155 	kret = ENOMEM;
156 
157 	/* Get a keyblock */
158 	if ((remain >= (3*sizeof(krb5_int32))) &&
159 	    (keyblock = (krb5_keyblock *) MALLOC(sizeof(krb5_keyblock)))) {
160 	    (void) memset(keyblock, 0, sizeof(krb5_keyblock));
161 
162 	    /* Get the enctype */
163 	    (void) krb5_ser_unpack_int32(&ibuf, &bp, &remain);
164 	    keyblock->enctype = (krb5_enctype) ibuf;
165 
166 	    /* Get the length */
167 	    (void) krb5_ser_unpack_int32(&ibuf, &bp, &remain);
168 	    keyblock->length = (int) ibuf;
169 
170 	    /* Get the string */
171 	    keyblock->contents = (krb5_octet *) MALLOC((size_t) (ibuf));
172 	    if ((keyblock->contents)&&
173 		!(kret = krb5_ser_unpack_bytes(keyblock->contents,
174 					       (size_t) ibuf,
175 					       &bp, &remain))) {
176 		kret = krb5_ser_unpack_int32(&ibuf, &bp, &remain);
177 		if (!kret && (ibuf == KV5M_KEYBLOCK)) {
178 		    kret = 0;
179 		    *buffer = bp;
180 		    *lenremain = remain;
181 		    keyblock->magic = KV5M_KEYBLOCK;
182 		    *argp = (krb5_pointer) keyblock;
183 		}
184 		else
185 		    kret = EINVAL;
186 	    }
187 	    if (kret) {
188 		if (keyblock->contents)
189 		    FREE(keyblock->contents, keyblock->length);
190 		FREE(keyblock, sizeof(krb5_keyblock));
191 	    }
192 	}
193     }
194     return(kret);
195 }
196 
197 /*
198  * Register the keyblock serializer.
199  */
200 krb5_error_code
201 krb5_ser_keyblock_init(krb5_context kcontext)
202 {
203     return(krb5_register_serializer(kcontext, &krb5_keyblock_ser_entry));
204 }
205