providers/implementations/kem/kem_util.c

   1 /*
   2  * Copyright 2022 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <string.h> /* for memcpy() */
  11 #include <openssl/core_names.h>
  12 #include <openssl/crypto.h>
  13 #include "eckem.h"
  14
  15 typedef struct {
  16     unsigned int id;
  17     const char *mode;
  18 } KEM_MODE;
  19
  20 static const KEM_MODE eckem_modename_id_map[] = {
  21     { KEM_MODE_DHKEM, OSSL_KEM_PARAM_OPERATION_DHKEM },
  22     { 0, NULL }
  23 };
  24
  25 int ossl_eckem_modename2id(const char *name)
  26 {
  27     size_t i;
  28
  29     if (name == NULL)
  30         return KEM_MODE_UNDEFINED;
  31
  32     for (i = 0; eckem_modename_id_map[i].mode != NULL; ++i) {
  33         if (OPENSSL_strcasecmp(name, eckem_modename_id_map[i].mode) == 0)
  34             return eckem_modename_id_map[i].id;
  35     }
  36     return KEM_MODE_UNDEFINED;
  37 }
  38
  39 /* suiteid = concat("KEM", I2OSP(kem_id, 2)) */
  40 void ossl_dhkem_getsuiteid(unsigned char suiteid[5], uint16_t kemid)
  41 {
  42     memcpy(suiteid, "KEM", 3);
  43     suiteid[3] = kemid >> 8;
  44     suiteid[4] = kemid & 0xFF;
  45 }