crypto/der.h

   1 /*
   2  * Copyright (c) 2022 Bytedance
   3  * Author: lei he <helei.sig11@bytedance.com>
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  17  *
  18  */
  19
  20 #ifndef QCRYPTO_ASN1_DECODER_H
  21 #define QCRYPTO_ASN1_DECODER_H
  22
  23 #include "qapi/error.h"
  24
  25 /* Simple decoder used to parse DER encoded rsa keys. */
  26
  27 /**
  28  *  @opaque: user context.
  29  *  @value: the starting address of |value| part of 'Tag-Length-Value' pattern.
  30  *  @vlen: length of the |value|.
  31  *  Returns: 0 for success, any other value is considered an error.
  32  */
  33 typedef int (*QCryptoDERDecodeCb) (void *opaque, const uint8_t *value,
  34                                    size_t vlen, Error **errp);
  35
  36 /**
  37  * qcrypto_der_decode_int:
  38  * @data: pointer to address of input data
  39  * @dlen: pointer to length of input data
  40  * @cb: callback invoked when decode succeed, if cb equals NULL, no
  41  * callback will be invoked
  42  * @opaque: parameter passed to cb
  43  *
  44  * Decode integer from DER-encoded data.
  45  *
  46  * Returns: On success, *data points to rest data, and *dlen
  47  * will be set to the rest length of data, if cb is not NULL, must
  48  * return 0 to make decode success, at last, the length of the data
  49  * part of the decoded INTEGER will be returned. Otherwise, -1 is
  50  * returned.
  51  */
  52 int qcrypto_der_decode_int(const uint8_t **data,
  53                            size_t *dlen,
  54                            QCryptoDERDecodeCb cb,
  55                            void *opaque,
  56                            Error **errp);
  57
  58 /**
  59  * qcrypto_der_decode_seq:
  60  *
  61  * Decode sequence from DER-encoded data, similar with der_decode_int.
  62  *
  63  * @data: pointer to address of input data
  64  * @dlen: pointer to length of input data
  65  * @cb: callback invoked when decode succeed, if cb equals NULL, no
  66  * callback will be invoked
  67  * @opaque: parameter passed to cb
  68  *
  69  * Returns: On success, *data points to rest data, and *dlen
  70  * will be set to the rest length of data, if cb is not NULL, must
  71  * return 0 to make decode success, at last, the length of the data
  72  * part of the decoded SEQUENCE will be returned. Otherwise, -1 is
  73  * returned.
  74  */
  75 int qcrypto_der_decode_seq(const uint8_t **data,
  76                            size_t *dlen,
  77                            QCryptoDERDecodeCb cb,
  78                            void *opaque,
  79                            Error **errp);
  80
  81 #endif  /* QCRYPTO_ASN1_DECODER_H */