asn1.h revision 310901 
1/*
2 * Copyright (c) 2001-2003
3 *	Fraunhofer Institute for Open Communication Systems (FhG Fokus).
4 *	All rights reserved.
5 *
6 * Author: Harti Brandt <harti@freebsd.org>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $Begemot: bsnmp/lib/asn1.h,v 1.20 2005/10/05 16:43:11 brandt_h Exp $
30 *
31 * ASN.1 for SNMP
32 */
33#ifndef asn1_h_
34#define asn1_h_
35
36#include <sys/types.h>
37
38struct asn_buf {
39	union {
40		u_char	*ptr;
41		const u_char *cptr;
42	}	asn_u;
43	size_t	asn_len;
44};
45#define asn_cptr	asn_u.cptr
46#define asn_ptr	asn_u.ptr
47
48/* these restrictions are in the SMI */
49#define ASN_MAXID	0xffffffff
50#define ASN_MAXOIDLEN	128
51
52/* the string needed for this (with trailing zero) */
53#define ASN_OIDSTRLEN	(ASN_MAXOIDLEN * (10 + 1) - 1 + 1)
54
55/* type of subidentifiers */
56typedef uint32_t asn_subid_t;
57
58struct asn_oid {
59	u_int	len;
60	asn_subid_t subs[ASN_MAXOIDLEN];
61};
62
63enum asn_err {
64	/* conversion was ok */
65	ASN_ERR_OK	= 0,
66	/* conversion failed and stopped */
67	ASN_ERR_FAILED	= 1 | 0x1000,
68	/* length field bad, value skipped */
69	ASN_ERR_BADLEN	= 2,
70	/* out of buffer, stopped */
71	ASN_ERR_EOBUF	= 3 | 0x1000,
72	/* length ok, but value is out of range */
73	ASN_ERR_RANGE	= 4,
74	/* not the expected tag, stopped */
75	ASN_ERR_TAG	= 5 | 0x1000,
76};
77#define ASN_ERR_STOPPED(E) (((E) & 0x1000) != 0)
78
79/* type for the length field of encoded values. The length is restricted
80 * to 65535, but using uint16_t would give conversion warnings on gcc */
81typedef uint32_t asn_len_t;	/* could be also uint16_t */
82
83/* maximal length of a long length field without the length of the length */
84#define ASN_MAXLEN	65535
85#define ASN_MAXLENLEN	2	/* number of bytes in a length */
86
87/* maximum size of an octet string as per SMIv2 */
88#define ASN_MAXOCTETSTRING 65535
89
90extern void (*asn_error)(const struct asn_buf *, const char *, ...);
91
92enum asn_err asn_get_header(struct asn_buf *, u_char *, asn_len_t *);
93enum asn_err asn_put_header(struct asn_buf *, u_char, asn_len_t);
94
95enum asn_err asn_put_temp_header(struct asn_buf *, u_char, u_char **);
96enum asn_err asn_commit_header(struct asn_buf *, u_char *, size_t *);
97
98enum asn_err asn_get_integer_raw(struct asn_buf *, asn_len_t, int32_t *);
99enum asn_err asn_get_integer(struct asn_buf *, int32_t *);
100enum asn_err asn_put_integer(struct asn_buf *, int32_t);
101
102enum asn_err asn_get_octetstring_raw(struct asn_buf *, asn_len_t, u_char *, u_int *);
103enum asn_err asn_get_octetstring(struct asn_buf *, u_char *, u_int *);
104enum asn_err asn_put_octetstring(struct asn_buf *, const u_char *, u_int);
105
106enum asn_err asn_get_null_raw(struct asn_buf *b, asn_len_t);
107enum asn_err asn_get_null(struct asn_buf *);
108enum asn_err asn_put_null(struct asn_buf *);
109
110enum asn_err asn_put_exception(struct asn_buf *, u_int);
111
112enum asn_err asn_get_objid_raw(struct asn_buf *, asn_len_t, struct asn_oid *);
113enum asn_err asn_get_objid(struct asn_buf *, struct asn_oid *);
114enum asn_err asn_put_objid(struct asn_buf *, const struct asn_oid *);
115
116enum asn_err asn_get_sequence(struct asn_buf *, asn_len_t *);
117
118enum asn_err asn_get_ipaddress_raw(struct asn_buf *, asn_len_t, u_char *);
119enum asn_err asn_get_ipaddress(struct asn_buf *, u_char *);
120enum asn_err asn_put_ipaddress(struct asn_buf *, const u_char *);
121
122enum asn_err asn_get_uint32_raw(struct asn_buf *, asn_len_t, uint32_t *);
123enum asn_err asn_put_uint32(struct asn_buf *, u_char, uint32_t);
124
125enum asn_err asn_get_counter64_raw(struct asn_buf *, asn_len_t, uint64_t *);
126enum asn_err asn_put_counter64(struct asn_buf *, uint64_t);
127
128enum asn_err asn_get_timeticks(struct asn_buf *, uint32_t *);
129enum asn_err asn_put_timeticks(struct asn_buf *, uint32_t);
130
131enum asn_err asn_skip(struct asn_buf *, asn_len_t);
132enum asn_err asn_pad(struct asn_buf *, asn_len_t);
133
134/*
135 * Utility functions for OIDs
136 */
137/* get a sub-OID from the middle of another OID */
138void asn_slice_oid(struct asn_oid *, const struct asn_oid *, u_int, u_int);
139
140/* append an OID to another one */
141void asn_append_oid(struct asn_oid *, const struct asn_oid *);
142
143/* compare two OIDs */
144int asn_compare_oid(const struct asn_oid *, const struct asn_oid *);
145
146/* check whether the first is a suboid of the second one */
147int asn_is_suboid(const struct asn_oid *, const struct asn_oid *);
148
149/* format an OID into a user buffer of size ASN_OIDSTRLEN */
150char *asn_oid2str_r(const struct asn_oid *, char *);
151
152/* format an OID into a private static buffer */
153char *asn_oid2str(const struct asn_oid *);
154
155enum {
156	ASN_TYPE_BOOLEAN	= 0x01,
157	ASN_TYPE_INTEGER	= 0x02,
158	ASN_TYPE_BITSTRING	= 0x03,
159	ASN_TYPE_OCTETSTRING	= 0x04,
160	ASN_TYPE_NULL		= 0x05,
161	ASN_TYPE_OBJID		= 0x06,
162	ASN_TYPE_SEQUENCE	= 0x10,
163
164	ASN_TYPE_CONSTRUCTED	= 0x20,
165	ASN_CLASS_UNIVERSAL	= 0x00,
166	ASN_CLASS_APPLICATION	= 0x40,
167	ASN_CLASS_CONTEXT	= 0x80,
168	ASN_CLASS_PRIVATE	= 0xc0,
169	ASN_TYPE_MASK		= 0x1f,
170
171	ASN_APP_IPADDRESS	= 0x00,
172	ASN_APP_COUNTER		= 0x01,
173	ASN_APP_GAUGE		= 0x02,
174	ASN_APP_TIMETICKS	= 0x03,
175	ASN_APP_OPAQUE		= 0x04,	/* not implemented */
176	ASN_APP_COUNTER64	= 0x06,
177
178	ASN_EXCEPT_NOSUCHOBJECT	= 0x00,
179	ASN_EXCEPT_NOSUCHINSTANCE = 0x01,
180	ASN_EXCEPT_ENDOFMIBVIEW	= 0x02,
181};
182
183#endif
184