/work/mbedtls-2.28.8/library/asn1parse.c

Source
/*
 *  Generic ASN.1 parsing
 *
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 */

#include "common.h"

#if defined(MBEDTLS_ASN1_PARSE_C)

#include "mbedtls/asn1.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"

#include <string.h>

#if defined(MBEDTLS_BIGNUM_C)
#include "mbedtls/bignum.h"
#endif

#include "mbedtls/platform.h"

/*
 * ASN.1 DER decoding routines
 */
int mbedtls_asn1_get_len(unsigned char **p,
                         const unsigned char *end,
                         size_t *len)
{
    if ((end - *p) < 1) {
        return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
    }

    if ((**p & 0x80) == 0) {
        *len = *(*p)++;
    } else {
        switch (**p & 0x7F) {
            case 1:
                if ((end - *p) < 2) {
                    return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
                }

                *len = (*p)[1];
                (*p) += 2;
                break;

            case 2:
                if ((end - *p) < 3) {
                    return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
                }

                *len = ((size_t) (*p)[1] << 8) | (*p)[2];
                (*p) += 3;
                break;

            case 3:
                if ((end - *p) < 4) {
                    return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
                }

                *len = ((size_t) (*p)[1] << 16) |
                       ((size_t) (*p)[2] << 8) | (*p)[3];
                (*p) += 4;
                break;

            case 4:
                if ((end - *p) < 5) {
                    return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
                }

                *len = ((size_t) (*p)[1] << 24) | ((size_t) (*p)[2] << 16) |
                       ((size_t) (*p)[3] << 8) |           (*p)[4];
                (*p) += 5;
                break;

            default:
                return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
        }
    }

    if (*len > (size_t) (end - *p)) {
        return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
    }

    return 0;
}

int mbedtls_asn1_get_tag(unsigned char **p,
                         const unsigned char *end,
                         size_t *len, int tag)
{
    if ((end - *p) < 1) {
        return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
    }

    if (**p != tag) {
        return MBEDTLS_ERR_ASN1_UNEXPECTED_TAG;
    }

    (*p)++;

    return mbedtls_asn1_get_len(p, end, len);
}

int mbedtls_asn1_get_bool(unsigned char **p,
                          const unsigned char *end,
                          int *val)
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
    size_t len;

    if ((ret = mbedtls_asn1_get_tag(p, end, &len, MBEDTLS_ASN1_BOOLEAN)) != 0) {
        return ret;
    }

    if (len != 1) {
        return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
    }

    *val = (**p != 0) ? 1 : 0;
    (*p)++;

    return 0;
}

static int asn1_get_tagged_int(unsigned char **p,
                               const unsigned char *end,
                               int tag, int *val)
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
    size_t len;

    if ((ret = mbedtls_asn1_get_tag(p, end, &len, tag)) != 0) {
        return ret;
    }

    /*
     * len==0 is malformed (0 must be represented as 020100 for INTEGER,
     * or 0A0100 for ENUMERATED tags
     */
    if (len == 0) {
        return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
    }
    /* This is a cryptography library. Reject negative integers. */
    if ((**p & 0x80) != 0) {
        return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
    }

    /* Skip leading zeros. */
    while (len > 0 && **p == 0) {
        ++(*p);
        --len;
    }

    /* Reject integers that don't fit in an int. This code assumes that
     * the int type has no padding bit. */
    if (len > sizeof(int)) {
        return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
    }
    if (len == sizeof(int) && (**p & 0x80) != 0) {
        return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
    }

    *val = 0;
    while (len-- > 0) {
        *val = (*val << 8) | **p;
        (*p)++;
    }

    return 0;
}

int mbedtls_asn1_get_int(unsigned char **p,
                         const unsigned char *end,
                         int *val)
{
    return asn1_get_tagged_int(p, end, MBEDTLS_ASN1_INTEGER, val);
}

int mbedtls_asn1_get_enum(unsigned char **p,
                          const unsigned char *end,
                          int *val)
{
    return asn1_get_tagged_int(p, end, MBEDTLS_ASN1_ENUMERATED, val);
}

#if defined(MBEDTLS_BIGNUM_C)
int mbedtls_asn1_get_mpi(unsigned char **p,
                         const unsigned char *end,
                         mbedtls_mpi *X)
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
    size_t len;

    if ((ret = mbedtls_asn1_get_tag(p, end, &len, MBEDTLS_ASN1_INTEGER)) != 0) {
        return ret;
    }

    ret = mbedtls_mpi_read_binary(X, *p, len);

    *p += len;

    return ret;
}
#endif /* MBEDTLS_BIGNUM_C */

int mbedtls_asn1_get_bitstring(unsigned char **p, const unsigned char *end,
                               mbedtls_asn1_bitstring *bs)
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;

    /* Certificate type is a single byte bitstring */
    if ((ret = mbedtls_asn1_get_tag(p, end, &bs->len, MBEDTLS_ASN1_BIT_STRING)) != 0) {
        return ret;
    }

    /* Check length, subtract one for actual bit string length */
    if (bs->len < 1) {
        return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
    }
    bs->len -= 1;

    /* Get number of unused bits, ensure unused bits <= 7 */
    bs->unused_bits = **p;
    if (bs->unused_bits > 7) {
        return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
    }
    (*p)++;

    /* Get actual bitstring */
    bs->p = *p;
    *p += bs->len;

    if (*p != end) {
        return MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
    }

    return 0;
}

/*
 * Traverse an ASN.1 "SEQUENCE OF <tag>"
 * and call a callback for each entry found.
 */
int mbedtls_asn1_traverse_sequence_of(
    unsigned char **p,
    const unsigned char *end,
    unsigned char tag_must_mask, unsigned char tag_must_val,
    unsigned char tag_may_mask, unsigned char tag_may_val,
    int (*cb)(void *ctx, int tag,
              unsigned char *start, size_t len),
    void *ctx)
{
    int ret;
    size_t len;

    /* Get main sequence tag */
    if ((ret = mbedtls_asn1_get_tag(p, end, &len,
                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
        return ret;
    }

    if (*p + len != end) {
        return MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
    }

    while (*p < end) {
        unsigned char const tag = *(*p)++;

        if ((tag & tag_must_mask) != tag_must_val) {
            return MBEDTLS_ERR_ASN1_UNEXPECTED_TAG;
        }

        if ((ret = mbedtls_asn1_get_len(p, end, &len)) != 0) {
            return ret;
        }

        if ((tag & tag_may_mask) == tag_may_val) {
            if (cb != NULL) {
                ret = cb(ctx, tag, *p, len);
                if (ret != 0) {
                    return ret;
                }
            }
        }

        *p += len;
    }

    return 0;
}

/*
 * Get a bit string without unused bits
 */
int mbedtls_asn1_get_bitstring_null(unsigned char **p, const unsigned char *end,
                                    size_t *len)
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;

    if ((ret = mbedtls_asn1_get_tag(p, end, len, MBEDTLS_ASN1_BIT_STRING)) != 0) {
        return ret;
    }

    if (*len == 0) {
        return MBEDTLS_ERR_ASN1_INVALID_DATA;
    }
    --(*len);

    if (**p != 0) {
        return MBEDTLS_ERR_ASN1_INVALID_DATA;
    }
    ++(*p);

    return 0;
}

void mbedtls_asn1_sequence_free(mbedtls_asn1_sequence *seq)
{
    while (seq != NULL) {
        mbedtls_asn1_sequence *next = seq->next;
        mbedtls_platform_zeroize(seq, sizeof(*seq));
        mbedtls_free(seq);
        seq = next;
    }
}

typedef struct {
    int tag;
    mbedtls_asn1_sequence *cur;
} asn1_get_sequence_of_cb_ctx_t;

static int asn1_get_sequence_of_cb(void *ctx,
                                   int tag,
                                   unsigned char *start,
                                   size_t len)
{
    asn1_get_sequence_of_cb_ctx_t *cb_ctx =
        (asn1_get_sequence_of_cb_ctx_t *) ctx;
    mbedtls_asn1_sequence *cur =
        cb_ctx->cur;

    if (cur->buf.p != NULL) {
        cur->next =
            mbedtls_calloc(1, sizeof(mbedtls_asn1_sequence));

        if (cur->next == NULL) {
            return MBEDTLS_ERR_ASN1_ALLOC_FAILED;
        }

        cur = cur->next;
    }

    cur->buf.p = start;
    cur->buf.len = len;
    cur->buf.tag = tag;

    cb_ctx->cur = cur;
    return 0;
}

/*
 *  Parses and splits an ASN.1 "SEQUENCE OF <tag>"
 */
int mbedtls_asn1_get_sequence_of(unsigned char **p,
                                 const unsigned char *end,
                                 mbedtls_asn1_sequence *cur,
                                 int tag)
{
    asn1_get_sequence_of_cb_ctx_t cb_ctx = { tag, cur };
    memset(cur, 0, sizeof(mbedtls_asn1_sequence));
    return mbedtls_asn1_traverse_sequence_of(
        p, end, 0xFF, tag, 0, 0,
        asn1_get_sequence_of_cb, &cb_ctx);
}

int mbedtls_asn1_get_alg(unsigned char **p,
                         const unsigned char *end,
                         mbedtls_asn1_buf *alg, mbedtls_asn1_buf *params)
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
    size_t len;

    if ((ret = mbedtls_asn1_get_tag(p, end, &len,
                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
        return ret;
    }

    if ((end - *p) < 1) {
        return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
    }

    alg->tag = **p;
    end = *p + len;

    if ((ret = mbedtls_asn1_get_tag(p, end, &alg->len, MBEDTLS_ASN1_OID)) != 0) {
        return ret;
    }

    alg->p = *p;
    *p += alg->len;

    if (*p == end) {
        mbedtls_platform_zeroize(params, sizeof(mbedtls_asn1_buf));
        return 0;
    }

    params->tag = **p;
    (*p)++;

    if ((ret = mbedtls_asn1_get_len(p, end, &params->len)) != 0) {
        return ret;
    }

    params->p = *p;
    *p += params->len;

    if (*p != end) {
        return MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
    }

    return 0;
}

int mbedtls_asn1_get_alg_null(unsigned char **p,
                              const unsigned char *end,
                              mbedtls_asn1_buf *alg)
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
    mbedtls_asn1_buf params;

    memset(&params, 0, sizeof(mbedtls_asn1_buf));

    if ((ret = mbedtls_asn1_get_alg(p, end, alg, &params)) != 0) {
        return ret;
    }

    if ((params.tag != MBEDTLS_ASN1_NULL && params.tag != 0) || params.len != 0) {
        return MBEDTLS_ERR_ASN1_INVALID_DATA;
    }

    return 0;
}

void mbedtls_asn1_free_named_data(mbedtls_asn1_named_data *cur)
{
    if (cur == NULL) {
        return;
    }

    mbedtls_free(cur->oid.p);
    mbedtls_free(cur->val.p);

    mbedtls_platform_zeroize(cur, sizeof(mbedtls_asn1_named_data));
}

void mbedtls_asn1_free_named_data_list(mbedtls_asn1_named_data **head)
{
    mbedtls_asn1_named_data *cur;

    while ((cur = *head) != NULL) {
        *head = cur->next;
        mbedtls_asn1_free_named_data(cur);
        mbedtls_free(cur);
    }
}

mbedtls_asn1_named_data *mbedtls_asn1_find_named_data(mbedtls_asn1_named_data *list,
                                                      const char *oid, size_t len)
{
    while (list != NULL) {
        if (list->oid.len == len &&
            memcmp(list->oid.p, oid, len) == 0) {
            break;
        }

        list = list->next;
    }

    return list;
}

#endif /* MBEDTLS_ASN1_PARSE_C */

Coverage Report

Created: 2025-10-28 06:49

Line	Count	Source
1		/*
2		* Generic ASN.1 parsing
3		*
4		* Copyright The Mbed TLS Contributors
5		* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6		*/
7
8		#include "common.h"
9
10		#if defined(MBEDTLS_ASN1_PARSE_C)
11
12		#include "mbedtls/asn1.h"
13		#include "mbedtls/platform_util.h"
14		#include "mbedtls/error.h"
15
16		#include <string.h>
17
18		#if defined(MBEDTLS_BIGNUM_C)
19		#include "mbedtls/bignum.h"
20		#endif
21
22		#include "mbedtls/platform.h"
23
24		/*
25		* ASN.1 DER decoding routines
26		*/
27		int mbedtls_asn1_get_len(unsigned char **p,
28		const unsigned char *end,
29		size_t *len)
30	0	{
31	0	if ((end - *p) < 1) {
32	0	return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
33	0	}
34
35	0	if ((**p & 0x80) == 0) {
36	0	len = (*p)++;
37	0	} else {
38	0	switch (**p & 0x7F) {
39	0	case 1:
40	0	if ((end - *p) < 2) {
41	0	return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
42	0	}
43
44	0	len = (p)[1];
45	0	(*p) += 2;
46	0	break;
47
48	0	case 2:
49	0	if ((end - *p) < 3) {
50	0	return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
51	0	}
52
53	0	len = ((size_t) (p)[1] << 8) \| (*p)[2];
54	0	(*p) += 3;
55	0	break;
56
57	0	case 3:
58	0	if ((end - *p) < 4) {
59	0	return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
60	0	}
61
62	0	len = ((size_t) (p)[1] << 16) \|
63	0	((size_t) (p)[2] << 8) \| (p)[3];
64	0	(*p) += 4;
65	0	break;
66
67	0	case 4:
68	0	if ((end - *p) < 5) {
69	0	return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
70	0	}
71
72	0	len = ((size_t) (p)[1] << 24) \| ((size_t) (*p)[2] << 16) \|
73	0	((size_t) (p)[3] << 8) \| (p)[4];
74	0	(*p) += 5;
75	0	break;
76
77	0	default:
78	0	return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
79	0	}
80	0	}
81
82	0	if (len > (size_t) (end - p)) {
83	0	return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
84	0	}
85
86	0	return 0;
87	0	}
88
89		int mbedtls_asn1_get_tag(unsigned char **p,
90		const unsigned char *end,
91		size_t *len, int tag)
92	0	{
93	0	if ((end - *p) < 1) {
94	0	return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
95	0	}
96
97	0	if (**p != tag) {
98	0	return MBEDTLS_ERR_ASN1_UNEXPECTED_TAG;
99	0	}
100
101	0	(*p)++;
102
103	0	return mbedtls_asn1_get_len(p, end, len);
104	0	}
105
106		int mbedtls_asn1_get_bool(unsigned char **p,
107		const unsigned char *end,
108		int *val)
109	0	{
110	0	int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
111	0	size_t len;
112
113	0	if ((ret = mbedtls_asn1_get_tag(p, end, &len, MBEDTLS_ASN1_BOOLEAN)) != 0) {
114	0	return ret;
115	0	}
116
117	0	if (len != 1) {
118	0	return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
119	0	}
120
121	0	val = (*p != 0) ? 1 : 0;
122	0	(*p)++;
123
124	0	return 0;
125	0	}
126
127		static int asn1_get_tagged_int(unsigned char **p,
128		const unsigned char *end,
129		int tag, int *val)
130	0	{
131	0	int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
132	0	size_t len;
133
134	0	if ((ret = mbedtls_asn1_get_tag(p, end, &len, tag)) != 0) {
135	0	return ret;
136	0	}
137
138		/*
139		* len==0 is malformed (0 must be represented as 020100 for INTEGER,
140		* or 0A0100 for ENUMERATED tags
141		*/
142	0	if (len == 0) {
143	0	return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
144	0	}
145		/* This is a cryptography library. Reject negative integers. */
146	0	if ((**p & 0x80) != 0) {
147	0	return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
148	0	}
149
150		/* Skip leading zeros. */
151	0	while (len > 0 && **p == 0) {
152	0	++(*p);
153	0	--len;
154	0	}
155
156		/* Reject integers that don't fit in an int. This code assumes that
157		* the int type has no padding bit. */
158	0	if (len > sizeof(int)) {
159	0	return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
160	0	}
161	0	if (len == sizeof(int) && (**p & 0x80) != 0) {
162	0	return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
163	0	}
164
165	0	*val = 0;
166	0	while (len-- > 0) {
167	0	val = (val << 8) \| **p;
168	0	(*p)++;
169	0	}
170
171	0	return 0;
172	0	}
173
174		int mbedtls_asn1_get_int(unsigned char **p,
175		const unsigned char *end,
176		int *val)
177	0	{
178	0	return asn1_get_tagged_int(p, end, MBEDTLS_ASN1_INTEGER, val);
179	0	}
180
181		int mbedtls_asn1_get_enum(unsigned char **p,
182		const unsigned char *end,
183		int *val)
184	0	{
185	0	return asn1_get_tagged_int(p, end, MBEDTLS_ASN1_ENUMERATED, val);
186	0	}
187
188		#if defined(MBEDTLS_BIGNUM_C)
189		int mbedtls_asn1_get_mpi(unsigned char **p,
190		const unsigned char *end,
191		mbedtls_mpi *X)
192	0	{
193	0	int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
194	0	size_t len;
195
196	0	if ((ret = mbedtls_asn1_get_tag(p, end, &len, MBEDTLS_ASN1_INTEGER)) != 0) {
197	0	return ret;
198	0	}
199
200	0	ret = mbedtls_mpi_read_binary(X, *p, len);
201
202	0	*p += len;
203
204	0	return ret;
205	0	}
206		#endif /* MBEDTLS_BIGNUM_C */
207
208		int mbedtls_asn1_get_bitstring(unsigned char *p, const unsigned char end,
209		mbedtls_asn1_bitstring *bs)
210	0	{
211	0	int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
212
213		/* Certificate type is a single byte bitstring */
214	0	if ((ret = mbedtls_asn1_get_tag(p, end, &bs->len, MBEDTLS_ASN1_BIT_STRING)) != 0) {
215	0	return ret;
216	0	}
217
218		/* Check length, subtract one for actual bit string length */
219	0	if (bs->len < 1) {
220	0	return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
221	0	}
222	0	bs->len -= 1;
223
224		/* Get number of unused bits, ensure unused bits <= 7 */
225	0	bs->unused_bits = **p;
226	0	if (bs->unused_bits > 7) {
227	0	return MBEDTLS_ERR_ASN1_INVALID_LENGTH;
228	0	}
229	0	(*p)++;
230
231		/* Get actual bitstring */
232	0	bs->p = *p;
233	0	*p += bs->len;
234
235	0	if (*p != end) {
236	0	return MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
237	0	}
238
239	0	return 0;
240	0	}
241
242		/*
243		* Traverse an ASN.1 "SEQUENCE OF <tag>"
244		* and call a callback for each entry found.
245		*/
246		int mbedtls_asn1_traverse_sequence_of(
247		unsigned char **p,
248		const unsigned char *end,
249		unsigned char tag_must_mask, unsigned char tag_must_val,
250		unsigned char tag_may_mask, unsigned char tag_may_val,
251		int (cb)(void ctx, int tag,
252		unsigned char *start, size_t len),
253		void *ctx)
254	0	{
255	0	int ret;
256	0	size_t len;
257
258		/* Get main sequence tag */
259	0	if ((ret = mbedtls_asn1_get_tag(p, end, &len,
260	0	MBEDTLS_ASN1_CONSTRUCTED \| MBEDTLS_ASN1_SEQUENCE)) != 0) {
261	0	return ret;
262	0	}
263
264	0	if (*p + len != end) {
265	0	return MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
266	0	}
267
268	0	while (*p < end) {
269	0	unsigned char const tag = (p)++;
270
271	0	if ((tag & tag_must_mask) != tag_must_val) {
272	0	return MBEDTLS_ERR_ASN1_UNEXPECTED_TAG;
273	0	}
274
275	0	if ((ret = mbedtls_asn1_get_len(p, end, &len)) != 0) {
276	0	return ret;
277	0	}
278
279	0	if ((tag & tag_may_mask) == tag_may_val) {
280	0	if (cb != NULL) {
281	0	ret = cb(ctx, tag, *p, len);
282	0	if (ret != 0) {
283	0	return ret;
284	0	}
285	0	}
286	0	}
287
288	0	*p += len;
289	0	}
290
291	0	return 0;
292	0	}
293
294		/*
295		* Get a bit string without unused bits
296		*/
297		int mbedtls_asn1_get_bitstring_null(unsigned char *p, const unsigned char end,
298		size_t *len)
299	0	{
300	0	int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
301
302	0	if ((ret = mbedtls_asn1_get_tag(p, end, len, MBEDTLS_ASN1_BIT_STRING)) != 0) {
303	0	return ret;
304	0	}
305
306	0	if (*len == 0) {
307	0	return MBEDTLS_ERR_ASN1_INVALID_DATA;
308	0	}
309	0	--(*len);
310
311	0	if (**p != 0) {
312	0	return MBEDTLS_ERR_ASN1_INVALID_DATA;
313	0	}
314	0	++(*p);
315
316	0	return 0;
317	0	}
318
319		void mbedtls_asn1_sequence_free(mbedtls_asn1_sequence *seq)
320	0	{
321	0	while (seq != NULL) {
322	0	mbedtls_asn1_sequence *next = seq->next;
323	0	mbedtls_platform_zeroize(seq, sizeof(*seq));
324	0	mbedtls_free(seq);
325	0	seq = next;
326	0	}
327	0	}
328
329		typedef struct {
330		int tag;
331		mbedtls_asn1_sequence *cur;
332		} asn1_get_sequence_of_cb_ctx_t;
333
334		static int asn1_get_sequence_of_cb(void *ctx,
335		int tag,
336		unsigned char *start,
337		size_t len)
338	0	{
339	0	asn1_get_sequence_of_cb_ctx_t *cb_ctx =
340	0	(asn1_get_sequence_of_cb_ctx_t *) ctx;
341	0	mbedtls_asn1_sequence *cur =
342	0	cb_ctx->cur;
343
344	0	if (cur->buf.p != NULL) {
345	0	cur->next =
346	0	mbedtls_calloc(1, sizeof(mbedtls_asn1_sequence));
347
348	0	if (cur->next == NULL) {
349	0	return MBEDTLS_ERR_ASN1_ALLOC_FAILED;
350	0	}
351
352	0	cur = cur->next;
353	0	}
354
355	0	cur->buf.p = start;
356	0	cur->buf.len = len;
357	0	cur->buf.tag = tag;
358
359	0	cb_ctx->cur = cur;
360	0	return 0;
361	0	}
362
363		/*
364		* Parses and splits an ASN.1 "SEQUENCE OF <tag>"
365		*/
366		int mbedtls_asn1_get_sequence_of(unsigned char **p,
367		const unsigned char *end,
368		mbedtls_asn1_sequence *cur,
369		int tag)
370	0	{
371	0	asn1_get_sequence_of_cb_ctx_t cb_ctx = { tag, cur };
372	0	memset(cur, 0, sizeof(mbedtls_asn1_sequence));
373	0	return mbedtls_asn1_traverse_sequence_of(
374	0	p, end, 0xFF, tag, 0, 0,
375	0	asn1_get_sequence_of_cb, &cb_ctx);
376	0	}
377
378		int mbedtls_asn1_get_alg(unsigned char **p,
379		const unsigned char *end,
380		mbedtls_asn1_buf alg, mbedtls_asn1_buf params)
381	0	{
382	0	int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
383	0	size_t len;
384
385	0	if ((ret = mbedtls_asn1_get_tag(p, end, &len,
386	0	MBEDTLS_ASN1_CONSTRUCTED \| MBEDTLS_ASN1_SEQUENCE)) != 0) {
387	0	return ret;
388	0	}
389
390	0	if ((end - *p) < 1) {
391	0	return MBEDTLS_ERR_ASN1_OUT_OF_DATA;
392	0	}
393
394	0	alg->tag = **p;
395	0	end = *p + len;
396
397	0	if ((ret = mbedtls_asn1_get_tag(p, end, &alg->len, MBEDTLS_ASN1_OID)) != 0) {
398	0	return ret;
399	0	}
400
401	0	alg->p = *p;
402	0	*p += alg->len;
403
404	0	if (*p == end) {
405	0	mbedtls_platform_zeroize(params, sizeof(mbedtls_asn1_buf));
406	0	return 0;
407	0	}
408
409	0	params->tag = **p;
410	0	(*p)++;
411
412	0	if ((ret = mbedtls_asn1_get_len(p, end, &params->len)) != 0) {
413	0	return ret;
414	0	}
415
416	0	params->p = *p;
417	0	*p += params->len;
418
419	0	if (*p != end) {
420	0	return MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
421	0	}
422
423	0	return 0;
424	0	}
425
426		int mbedtls_asn1_get_alg_null(unsigned char **p,
427		const unsigned char *end,
428		mbedtls_asn1_buf *alg)
429	0	{
430	0	int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
431	0	mbedtls_asn1_buf params;
432
433	0	memset(&params, 0, sizeof(mbedtls_asn1_buf));
434
435	0	if ((ret = mbedtls_asn1_get_alg(p, end, alg, &params)) != 0) {
436	0	return ret;
437	0	}
438
439	0	if ((params.tag != MBEDTLS_ASN1_NULL && params.tag != 0) \|\| params.len != 0) {
440	0	return MBEDTLS_ERR_ASN1_INVALID_DATA;
441	0	}
442
443	0	return 0;
444	0	}
445
446		void mbedtls_asn1_free_named_data(mbedtls_asn1_named_data *cur)
447	0	{
448	0	if (cur == NULL) {
449	0	return;
450	0	}
451
452	0	mbedtls_free(cur->oid.p);
453	0	mbedtls_free(cur->val.p);
454
455	0	mbedtls_platform_zeroize(cur, sizeof(mbedtls_asn1_named_data));
456	0	}
457
458		void mbedtls_asn1_free_named_data_list(mbedtls_asn1_named_data **head)
459	0	{
460	0	mbedtls_asn1_named_data *cur;
461
462	0	while ((cur = *head) != NULL) {
463	0	*head = cur->next;
464	0	mbedtls_asn1_free_named_data(cur);
465	0	mbedtls_free(cur);
466	0	}
467	0	}
468
469		mbedtls_asn1_named_data mbedtls_asn1_find_named_data(mbedtls_asn1_named_data list,
470		const char *oid, size_t len)
471	0	{
472	0	while (list != NULL) {
473	0	if (list->oid.len == len &&
474	0	memcmp(list->oid.p, oid, len) == 0) {
475	0	break;
476	0	}
477
478	0	list = list->next;
479	0	}
480
481	0	return list;
482	0	}
483
484		#endif /* MBEDTLS_ASN1_PARSE_C */