summaryrefslogtreecommitdiffstats
path: root/crypto/asn1/bio_ndef.c
blob: 0f206b24977e1e0124e1d2629ee72b9b4db65fb2 (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
/*
 * Copyright 2008-2016 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the OpenSSL license (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include <openssl/bio.h>
#include <openssl/err.h>

#include <stdio.h>

/* Experimental NDEF ASN1 BIO support routines */

/*
 * The usage is quite simple, initialize an ASN1 structure, get a BIO from it
 * then any data written through the BIO will end up translated to
 * appropriate format on the fly. The data is streamed out and does *not*
 * need to be all held in memory at once. When the BIO is flushed the output
 * is finalized and any signatures etc written out. The BIO is a 'proper'
 * BIO and can handle non blocking I/O correctly. The usage is simple. The
 * implementation is *not*...
 */

/* BIO support data stored in the ASN1 BIO ex_arg */

typedef struct ndef_aux_st {
    /* ASN1 structure this BIO refers to */
    ASN1_VALUE *val;
    const ASN1_ITEM *it;
    /* Top of the BIO chain */
    BIO *ndef_bio;
    /* Output BIO */
    BIO *out;
    /* Boundary where content is inserted */
    unsigned char **boundary;
    /* DER buffer start */
    unsigned char *derbuf;
} NDEF_SUPPORT;

static int ndef_prefix(BIO *b, unsigned char **pbuf, int *plen, void *parg);
static int ndef_prefix_free(BIO *b, unsigned char **pbuf, int *plen,
                            void *parg);
static int ndef_suffix(BIO *b, unsigned char **pbuf, int *plen, void *parg);
static int ndef_suffix_free(BIO *b, unsigned char **pbuf, int *plen,
                            void *parg);

BIO *BIO_new_NDEF(BIO *out, ASN1_VALUE *val, const ASN1_ITEM *it)
{
    NDEF_SUPPORT *ndef_aux = NULL;
    BIO *asn_bio = NULL;
    const ASN1_AUX *aux = it->funcs;
    ASN1_STREAM_ARG sarg;

    if (!aux || !aux->asn1_cb) {
        ASN1err(ASN1_F_BIO_NEW_NDEF, ASN1_R_STREAMING_NOT_SUPPORTED);
        return NULL;
    }
    ndef_aux = OPENSSL_zalloc(sizeof(*ndef_aux));
    asn_bio = BIO_new(BIO_f_asn1());
    if (ndef_aux == NULL || asn_bio == NULL)
        goto err;

    /* ASN1 bio needs to be next to output BIO */
    out = BIO_push(asn_bio, out);
    if (out == NULL)
        goto err;

    BIO_asn1_set_prefix(asn_bio, ndef_prefix, ndef_prefix_free);
    BIO_asn1_set_suffix(asn_bio, ndef_suffix, ndef_suffix_free);

    /*
     * Now let callback prepends any digest, cipher etc BIOs ASN1 structure
     * needs.
     */

    sarg.out = out;
    sarg.ndef_bio = NULL;
    sarg.boundary = NULL;

    if (aux->asn1_cb(ASN1_OP_STREAM_PRE, &val, it, &sarg) <= 0)
        goto err;

    ndef_aux->val = val;
    ndef_aux->it = it;
    ndef_aux->ndef_bio = sarg.ndef_bio;
    ndef_aux->boundary = sarg.boundary;
    ndef_aux->out = out;

    BIO_ctrl(asn_bio, BIO_C_SET_EX_ARG, 0, ndef_aux);

    return sarg.ndef_bio;

 err:
    BIO_free(asn_bio);
    OPENSSL_free(ndef_aux);
    return NULL;
}

static int ndef_prefix(BIO *b, unsigned char **pbuf, int *plen, void *parg)
{
    NDEF_SUPPORT *ndef_aux;
    unsigned char *p;
    int derlen;

    if (!parg)
        return 0;

    ndef_aux = *(NDEF_SUPPORT **)parg;

    derlen = ASN1_item_ndef_i2d(ndef_aux->val, NULL, ndef_aux->it);
    p = OPENSSL_malloc(derlen);
    if (p == NULL)
        return 0;

    ndef_aux->derbuf = p;
    *pbuf = p;
    derlen = ASN1_item_ndef_i2d(ndef_aux->val, &p, ndef_aux->it);

    if (!*ndef_aux->boundary)
        return 0;

    *plen = *ndef_aux->boundary - *pbuf;

    return 1;
}

static int ndef_prefix_free(BIO *b, unsigned char **pbuf, int *plen,
                            void *parg)
{
    NDEF_SUPPORT *ndef_aux;

    if (!parg)
        return 0;

    ndef_aux = *(NDEF_SUPPORT **)parg;

    OPENSSL_free(ndef_aux->derbuf);

    ndef_aux->derbuf = NULL;
    *pbuf = NULL;
    *plen = 0;
    return 1;
}

static int ndef_suffix_free(BIO *b, unsigned char **pbuf, int *plen,
                            void *parg)
{
    NDEF_SUPPORT **pndef_aux = (NDEF_SUPPORT **)parg;
    if (!ndef_prefix_free(b, pbuf, plen, parg))
        return 0;
    OPENSSL_free(*pndef_aux);
    *pndef_aux = NULL;
    return 1;
}

static int ndef_suffix(BIO *b, unsigned char **pbuf, int *plen, void *parg)
{
    NDEF_SUPPORT *ndef_aux;
    unsigned char *p;
    int derlen;
    const ASN1_AUX *aux;
    ASN1_STREAM_ARG sarg;

    if (!parg)
        return 0;

    ndef_aux = *(NDEF_SUPPORT **)parg;

    aux = ndef_aux->it->funcs;

    /* Finalize structures */
    sarg.ndef_bio = ndef_aux->ndef_bio;
    sarg.out = ndef_aux->out;
    sarg.boundary = ndef_aux->boundary;
    if (aux->asn1_cb(ASN1_OP_STREAM_POST,
                     &ndef_aux->val, ndef_aux->it, &sarg) <= 0)
        return 0;

    derlen = ASN1_item_ndef_i2d(ndef_aux->val, NULL, ndef_aux->it);
    p = OPENSSL_malloc(derlen);
    if (p == NULL)
        return 0;

    ndef_aux->derbuf = p;
    *pbuf = p;
    derlen = ASN1_item_ndef_i2d(ndef_aux->val, &p, ndef_aux->it);

    if (!*ndef_aux->boundary)
        return 0;
    *pbuf = *ndef_aux->boundary;
    *plen = derlen - (*ndef_aux->boundary - ndef_aux->derbuf);

    return 1;
}