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 typedef struct QCryptoEncodeContext QCryptoEncodeContext;
  26
  27 /* rsaEncryption: 1.2.840.113549.1.1.1 */
  28 #define QCRYPTO_OID_rsaEncryption "\x2A\x86\x48\x86\xF7\x0D\x01\x01\x01"
  29
  30 /* Simple decoder used to parse DER encoded rsa keys. */
  31
  32 /**
  33  *  @opaque: user context.
  34  *  @value: the starting address of |value| part of 'Tag-Length-Value' pattern.
  35  *  @vlen: length of the |value|.
  36  *  Returns: 0 for success, any other value is considered an error.
  37  */
  38 typedef int (*QCryptoDERDecodeCb) (void *opaque, const uint8_t *value,
  39                                    size_t vlen, Error **errp);
  40
  41 /**
  42  * qcrypto_der_decode_int:
  43  * @data: pointer to address of input data
  44  * @dlen: pointer to length of input data
  45  * @cb: callback invoked when decode succeed, if cb equals NULL, no
  46  * callback will be invoked
  47  * @opaque: parameter passed to cb
  48  *
  49  * Decode integer from DER-encoded data.
  50  *
  51  * Returns: On success, *data points to rest data, and *dlen
  52  * will be set to the rest length of data, if cb is not NULL, must
  53  * return 0 to make decode success, at last, the length of the data
  54  * part of the decoded INTEGER will be returned. Otherwise, -1 is
  55  * returned and the valued of *data and *dlen keep unchanged.
  56  */
  57 int qcrypto_der_decode_int(const uint8_t **data,
  58                            size_t *dlen,
  59                            QCryptoDERDecodeCb cb,
  60                            void *opaque,
  61                            Error **errp);
  62 /**
  63  * qcrypto_der_decode_seq:
  64  *
  65  * Decode sequence from DER-encoded data, similar with der_decode_int.
  66  *
  67  * @data: pointer to address of input data
  68  * @dlen: pointer to length of input data
  69  * @cb: callback invoked when decode succeed, if cb equals NULL, no
  70  * callback will be invoked
  71  * @opaque: parameter passed to cb
  72  *
  73  * Returns: On success, *data points to rest data, and *dlen
  74  * will be set to the rest length of data, if cb is not NULL, must
  75  * return 0 to make decode success, at last, the length of the data
  76  * part of the decoded SEQUENCE will be returned. Otherwise, -1 is
  77  * returned and the valued of *data and *dlen keep unchanged.
  78  */
  79 int qcrypto_der_decode_seq(const uint8_t **data,
  80                            size_t *dlen,
  81                            QCryptoDERDecodeCb cb,
  82                            void *opaque,
  83                            Error **errp);
  84
  85 /**
  86  * qcrypto_der_decode_oid:
  87  *
  88  * Decode OID from DER-encoded data, similar with der_decode_int.
  89  *
  90  * @data: pointer to address of input data
  91  * @dlen: pointer to length of input data
  92  * @cb: callback invoked when decode succeed, if cb equals NULL, no
  93  * callback will be invoked
  94  * @opaque: parameter passed to cb
  95  *
  96  * Returns: On success, *data points to rest data, and *dlen
  97  * will be set to the rest length of data, if cb is not NULL, must
  98  * return 0 to make decode success, at last, the length of the data
  99  * part of the decoded OID will be returned. Otherwise, -1 is
 100  * returned and the valued of *data and *dlen keep unchanged.
 101  */
 102 int qcrypto_der_decode_oid(const uint8_t **data,
 103                            size_t *dlen,
 104                            QCryptoDERDecodeCb cb,
 105                            void *opaque,
 106                            Error **errp);
 107
 108 /**
 109  * qcrypto_der_decode_octet_str:
 110  *
 111  * Decode OCTET STRING from DER-encoded data, similar with der_decode_int.
 112  *
 113  * @data: pointer to address of input data
 114  * @dlen: pointer to length of input data
 115  * @cb: callback invoked when decode succeed, if cb equals NULL, no
 116  * callback will be invoked
 117  * @opaque: parameter passed to cb
 118  *
 119  * Returns: On success, *data points to rest data, and *dlen
 120  * will be set to the rest length of data, if cb is not NULL, must
 121  * return 0 to make decode success, at last, the length of the data
 122  * part of the decoded OCTET STRING will be returned. Otherwise, -1 is
 123  * returned and the valued of *data and *dlen keep unchanged.
 124  */
 125 int qcrypto_der_decode_octet_str(const uint8_t **data,
 126                                  size_t *dlen,
 127                                  QCryptoDERDecodeCb cb,
 128                                  void *opaque,
 129                                  Error **errp);
 130
 131 /**
 132  * qcrypto_der_decode_bit_str:
 133  *
 134  * Decode BIT STRING from DER-encoded data, similar with der_decode_int.
 135  *
 136  * @data: pointer to address of input data
 137  * @dlen: pointer to length of input data
 138  * @cb: callback invoked when decode succeed, if cb equals NULL, no
 139  * callback will be invoked
 140  * @opaque: parameter passed to cb
 141  *
 142  * Returns: On success, *data points to rest data, and *dlen
 143  * will be set to the rest length of data, if cb is not NULL, must
 144  * return 0 to make decode success, at last, the length of the data
 145  * part of the decoded BIT STRING will be returned. Otherwise, -1 is
 146  * returned and the valued of *data and *dlen keep unchanged.
 147  */
 148 int qcrypto_der_decode_bit_str(const uint8_t **data,
 149                                size_t *dlen,
 150                                QCryptoDERDecodeCb cb,
 151                                void *opaque,
 152                                Error **errp);
 153
 154
 155 /**
 156  * qcrypto_der_decode_ctx_tag:
 157  *
 158  * Decode context specific tag
 159  *
 160  * @data: pointer to address of input data
 161  * @dlen: pointer to length of input data
 162  * @tag: expected value of context specific tag
 163  * @cb: callback invoked when decode succeed, if cb equals NULL, no
 164  * callback will be invoked
 165  * @opaque: parameter passed to cb
 166  *
 167  * Returns: On success, *data points to rest data, and *dlen
 168  * will be set to the rest length of data, if cb is not NULL, must
 169  * return 0 to make decode success, at last, the length of the data
 170  * part of the decoded BIT STRING will be returned. Otherwise, -1 is
 171  * returned and the valued of *data and *dlen keep unchanged.
 172  */
 173 int qcrypto_der_decode_ctx_tag(const uint8_t **data,
 174                                size_t *dlen, int tag_id,
 175                                QCryptoDERDecodeCb cb,
 176                                void *opaque,
 177                                Error **errp);
 178
 179 /**
 180  * qcrypto_der_encode_ctx_new:
 181  *
 182  * Allocate a context used for der encoding.
 183  */
 184 QCryptoEncodeContext *qcrypto_der_encode_ctx_new(void);
 185
 186 /**
 187  * qcrypto_der_encode_seq_begin:
 188  * @ctx: the encode context.
 189  *
 190  * Start encoding a SEQUENCE for ctx.
 191  *
 192  */
 193 void qcrypto_der_encode_seq_begin(QCryptoEncodeContext *ctx);
 194
 195 /**
 196  * qcrypto_der_encode_seq_begin:
 197  * @ctx: the encode context.
 198  *
 199  * Finish uencoding a SEQUENCE for ctx.
 200  *
 201  */
 202 void qcrypto_der_encode_seq_end(QCryptoEncodeContext *ctx);
 203
 204
 205 /**
 206  * qcrypto_der_encode_oid:
 207  * @ctx: the encode context.
 208  * @src: the source data of oid, note it should be already encoded, this
 209  * function only add tag and length part for it.
 210  *
 211  * Encode an oid into ctx.
 212  */
 213 void qcrypto_der_encode_oid(QCryptoEncodeContext *ctx,
 214                             const uint8_t *src, size_t src_len);
 215
 216 /**
 217  * qcrypto_der_encode_int:
 218  * @ctx: the encode context.
 219  * @src: the source data of integer, note it should be already encoded, this
 220  * function only add tag and length part for it.
 221  *
 222  * Encode an integer into ctx.
 223  */
 224 void qcrypto_der_encode_int(QCryptoEncodeContext *ctx,
 225                             const uint8_t *src, size_t src_len);
 226
 227 /**
 228  * qcrypto_der_encode_null:
 229  * @ctx: the encode context.
 230  *
 231  * Encode a null into ctx.
 232  */
 233 void qcrypto_der_encode_null(QCryptoEncodeContext *ctx);
 234
 235 /**
 236  * qcrypto_der_encode_octet_str:
 237  * @ctx: the encode context.
 238  * @src: the source data of the octet string.
 239  *
 240  * Encode a octet string into ctx.
 241  */
 242 void qcrypto_der_encode_octet_str(QCryptoEncodeContext *ctx,
 243                                   const uint8_t *src, size_t src_len);
 244
 245 /**
 246  * qcrypto_der_encode_octet_str_begin:
 247  * @ctx: the encode context.
 248  *
 249  * Start encoding a octet string, All fields between
 250  * qcrypto_der_encode_octet_str_begin and qcrypto_der_encode_octet_str_end
 251  * are encoded as an octet string. This is useful when we need to encode a
 252  * encoded SEQUENCE as OCTET STRING.
 253  */
 254 void qcrypto_der_encode_octet_str_begin(QCryptoEncodeContext *ctx);
 255
 256 /**
 257  * qcrypto_der_encode_octet_str_end:
 258  * @ctx: the encode context.
 259  *
 260  * Finish encoding a octet string, All fields between
 261  * qcrypto_der_encode_octet_str_begin and qcrypto_der_encode_octet_str_end
 262  * are encoded as an octet string. This is useful when we need to encode a
 263  * encoded SEQUENCE as OCTET STRING.
 264  */
 265 void qcrypto_der_encode_octet_str_end(QCryptoEncodeContext *ctx);
 266
 267 /**
 268  * qcrypto_der_encode_ctx_buffer_len:
 269  * @ctx: the encode context.
 270  *
 271  * Compute the expected buffer size to save all encoded things.
 272  */
 273 size_t qcrypto_der_encode_ctx_buffer_len(QCryptoEncodeContext *ctx);
 274
 275 /**
 276  * qcrypto_der_encode_ctx_flush_and_free:
 277  * @ctx: the encode context.
 278  * @dst: the destination to save the encoded data, the length of dst should
 279  * not less than qcrypto_der_encode_cxt_buffer_len
 280  *
 281  * Flush all encoded data into dst, then free ctx.
 282  */
 283 void qcrypto_der_encode_ctx_flush_and_free(QCryptoEncodeContext *ctx,
 284                                            uint8_t *dst);
 285
 286 #endif  /* QCRYPTO_ASN1_DECODER_H */