providers/implementations/exchange/ecx_exch.c

   1 /*
   2  * Copyright 2020-2023 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 <openssl/crypto.h>
  11 #include <openssl/core_dispatch.h>
  12 #include <openssl/core_names.h>
  13 #include <openssl/params.h>
  14 #include <openssl/err.h>
  15 #include <openssl/proverr.h>
  16 #include "internal/cryptlib.h"
  17 #include "crypto/ecx.h"
  18 #include "prov/implementations.h"
  19 #include "prov/providercommon.h"
  20
  21 static OSSL_FUNC_keyexch_newctx_fn x25519_newctx;
  22 static OSSL_FUNC_keyexch_newctx_fn x448_newctx;
  23 static OSSL_FUNC_keyexch_init_fn ecx_init;
  24 static OSSL_FUNC_keyexch_set_peer_fn ecx_set_peer;
  25 static OSSL_FUNC_keyexch_derive_fn ecx_derive;
  26 static OSSL_FUNC_keyexch_freectx_fn ecx_freectx;
  27 static OSSL_FUNC_keyexch_dupctx_fn ecx_dupctx;
  28
  29 /*
  30  * What's passed as an actual key is defined by the KEYMGMT interface.
  31  * We happen to know that our KEYMGMT simply passes ECX_KEY structures, so
  32  * we use that here too.
  33  */
  34
  35 typedef struct {
  36     size_t keylen;
  37     ECX_KEY *key;
  38     ECX_KEY *peerkey;
  39 } PROV_ECX_CTX;
  40
  41 static void *ecx_newctx(void *provctx, size_t keylen)
  42 {
  43     PROV_ECX_CTX *ctx;
  44
  45     if (!ossl_prov_is_running())
  46         return NULL;
  47
  48     ctx = OPENSSL_zalloc(sizeof(PROV_ECX_CTX));
  49     if (ctx == NULL)
  50         return NULL;
  51
  52     ctx->keylen = keylen;
  53
  54     return ctx;
  55 }
  56
  57 static void *x25519_newctx(void *provctx)
  58 {
  59     return ecx_newctx(provctx, X25519_KEYLEN);
  60 }
  61
  62 static void *x448_newctx(void *provctx)
  63 {
  64     return ecx_newctx(provctx, X448_KEYLEN);
  65 }
  66
  67 static int ecx_init(void *vecxctx, void *vkey,
  68                     ossl_unused const OSSL_PARAM params[])
  69 {
  70     PROV_ECX_CTX *ecxctx = (PROV_ECX_CTX *)vecxctx;
  71     ECX_KEY *key = vkey;
  72
  73     if (!ossl_prov_is_running())
  74         return 0;
  75
  76     if (ecxctx == NULL
  77             || key == NULL
  78             || key->keylen != ecxctx->keylen
  79             || !ossl_ecx_key_up_ref(key)) {
  80         ERR_raise(ERR_LIB_PROV, ERR_R_INTERNAL_ERROR);
  81         return 0;
  82     }
  83
  84     ossl_ecx_key_free(ecxctx->key);
  85     ecxctx->key = key;
  86
  87     return 1;
  88 }
  89
  90 static int ecx_set_peer(void *vecxctx, void *vkey)
  91 {
  92     PROV_ECX_CTX *ecxctx = (PROV_ECX_CTX *)vecxctx;
  93     ECX_KEY *key = vkey;
  94
  95     if (!ossl_prov_is_running())
  96         return 0;
  97
  98     if (ecxctx == NULL
  99             || key == NULL
 100             || key->keylen != ecxctx->keylen
 101             || !ossl_ecx_key_up_ref(key)) {
 102         ERR_raise(ERR_LIB_PROV, ERR_R_INTERNAL_ERROR);
 103         return 0;
 104     }
 105     ossl_ecx_key_free(ecxctx->peerkey);
 106     ecxctx->peerkey = key;
 107
 108     return 1;
 109 }
 110
 111 static int ecx_derive(void *vecxctx, unsigned char *secret, size_t *secretlen,
 112                       size_t outlen)
 113 {
 114     PROV_ECX_CTX *ecxctx = (PROV_ECX_CTX *)vecxctx;
 115
 116     if (!ossl_prov_is_running())
 117         return 0;
 118     return ossl_ecx_compute_key(ecxctx->peerkey, ecxctx->key, ecxctx->keylen,
 119                                 secret, secretlen, outlen);
 120 }
 121
 122 static void ecx_freectx(void *vecxctx)
 123 {
 124     PROV_ECX_CTX *ecxctx = (PROV_ECX_CTX *)vecxctx;
 125
 126     ossl_ecx_key_free(ecxctx->key);
 127     ossl_ecx_key_free(ecxctx->peerkey);
 128
 129     OPENSSL_free(ecxctx);
 130 }
 131
 132 static void *ecx_dupctx(void *vecxctx)
 133 {
 134     PROV_ECX_CTX *srcctx = (PROV_ECX_CTX *)vecxctx;
 135     PROV_ECX_CTX *dstctx;
 136
 137     if (!ossl_prov_is_running())
 138         return NULL;
 139
 140     dstctx = OPENSSL_zalloc(sizeof(*srcctx));
 141     if (dstctx == NULL)
 142         return NULL;
 143
 144     *dstctx = *srcctx;
 145     if (dstctx->key != NULL && !ossl_ecx_key_up_ref(dstctx->key)) {
 146         ERR_raise(ERR_LIB_PROV, ERR_R_INTERNAL_ERROR);
 147         OPENSSL_free(dstctx);
 148         return NULL;
 149     }
 150
 151     if (dstctx->peerkey != NULL && !ossl_ecx_key_up_ref(dstctx->peerkey)) {
 152         ERR_raise(ERR_LIB_PROV, ERR_R_INTERNAL_ERROR);
 153         ossl_ecx_key_free(dstctx->key);
 154         OPENSSL_free(dstctx);
 155         return NULL;
 156     }
 157
 158     return dstctx;
 159 }
 160
 161 const OSSL_DISPATCH ossl_x25519_keyexch_functions[] = {
 162     { OSSL_FUNC_KEYEXCH_NEWCTX, (void (*)(void))x25519_newctx },
 163     { OSSL_FUNC_KEYEXCH_INIT, (void (*)(void))ecx_init },
 164     { OSSL_FUNC_KEYEXCH_DERIVE, (void (*)(void))ecx_derive },
 165     { OSSL_FUNC_KEYEXCH_SET_PEER, (void (*)(void))ecx_set_peer },
 166     { OSSL_FUNC_KEYEXCH_FREECTX, (void (*)(void))ecx_freectx },
 167     { OSSL_FUNC_KEYEXCH_DUPCTX, (void (*)(void))ecx_dupctx },
 168     OSSL_DISPATCH_END
 169 };
 170
 171 const OSSL_DISPATCH ossl_x448_keyexch_functions[] = {
 172     { OSSL_FUNC_KEYEXCH_NEWCTX, (void (*)(void))x448_newctx },
 173     { OSSL_FUNC_KEYEXCH_INIT, (void (*)(void))ecx_init },
 174     { OSSL_FUNC_KEYEXCH_DERIVE, (void (*)(void))ecx_derive },
 175     { OSSL_FUNC_KEYEXCH_SET_PEER, (void (*)(void))ecx_set_peer },
 176     { OSSL_FUNC_KEYEXCH_FREECTX, (void (*)(void))ecx_freectx },
 177     { OSSL_FUNC_KEYEXCH_DUPCTX, (void (*)(void))ecx_dupctx },
 178     OSSL_DISPATCH_END
 179 };