providers/implementations/macs/gmac_prov.c

   1 /*
   2  * Copyright 2018-2020 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 <stdlib.h>
  11 #include <openssl/core_dispatch.h>
  12 #include <openssl/core_names.h>
  13 #include <openssl/params.h>
  14 #include <openssl/engine.h>
  15 #include <openssl/evp.h>
  16 #include <openssl/err.h>
  17 #include <openssl/proverr.h>
  18
  19 #include "prov/implementations.h"
  20 #include "prov/provider_ctx.h"
  21 #include "prov/provider_util.h"
  22 #include "prov/providercommon.h"
  23
  24 /*
  25  * Forward declaration of everything implemented here.  This is not strictly
  26  * necessary for the compiler, but provides an assurance that the signatures
  27  * of the functions in the dispatch table are correct.
  28  */
  29 static OSSL_FUNC_mac_newctx_fn gmac_new;
  30 static OSSL_FUNC_mac_dupctx_fn gmac_dup;
  31 static OSSL_FUNC_mac_freectx_fn gmac_free;
  32 static OSSL_FUNC_mac_gettable_params_fn gmac_gettable_params;
  33 static OSSL_FUNC_mac_get_params_fn gmac_get_params;
  34 static OSSL_FUNC_mac_settable_ctx_params_fn gmac_settable_ctx_params;
  35 static OSSL_FUNC_mac_set_ctx_params_fn gmac_set_ctx_params;
  36 static OSSL_FUNC_mac_init_fn gmac_init;
  37 static OSSL_FUNC_mac_update_fn gmac_update;
  38 static OSSL_FUNC_mac_final_fn gmac_final;
  39
  40 /* local GMAC pkey structure */
  41
  42 struct gmac_data_st {
  43     void *provctx;
  44     EVP_CIPHER_CTX *ctx;         /* Cipher context */
  45     PROV_CIPHER cipher;
  46 };
  47
  48 static void gmac_free(void *vmacctx)
  49 {
  50     struct gmac_data_st *macctx = vmacctx;
  51
  52     if (macctx != NULL) {
  53         EVP_CIPHER_CTX_free(macctx->ctx);
  54         ossl_prov_cipher_reset(&macctx->cipher);
  55         OPENSSL_free(macctx);
  56     }
  57 }
  58
  59 static void *gmac_new(void *provctx)
  60 {
  61     struct gmac_data_st *macctx;
  62
  63     if (!ossl_prov_is_running())
  64         return NULL;
  65
  66     if ((macctx = OPENSSL_zalloc(sizeof(*macctx))) == NULL
  67         || (macctx->ctx = EVP_CIPHER_CTX_new()) == NULL) {
  68         gmac_free(macctx);
  69         return NULL;
  70     }
  71     macctx->provctx = provctx;
  72
  73     return macctx;
  74 }
  75
  76 static void *gmac_dup(void *vsrc)
  77 {
  78     struct gmac_data_st *src = vsrc;
  79     struct gmac_data_st *dst;
  80
  81     if (!ossl_prov_is_running())
  82         return NULL;
  83
  84     dst = gmac_new(src->provctx);
  85     if (dst == NULL)
  86         return NULL;
  87
  88     if (!EVP_CIPHER_CTX_copy(dst->ctx, src->ctx)
  89         || !ossl_prov_cipher_copy(&dst->cipher, &src->cipher)) {
  90         gmac_free(dst);
  91         return NULL;
  92     }
  93     return dst;
  94 }
  95
  96 static size_t gmac_size(void)
  97 {
  98     return EVP_GCM_TLS_TAG_LEN;
  99 }
 100
 101 static int gmac_init(void *vmacctx)
 102 {
 103     return ossl_prov_is_running();
 104 }
 105
 106 static int gmac_update(void *vmacctx, const unsigned char *data,
 107                        size_t datalen)
 108 {
 109     struct gmac_data_st *macctx = vmacctx;
 110     EVP_CIPHER_CTX *ctx = macctx->ctx;
 111     int outlen;
 112
 113     if (datalen == 0)
 114         return 1;
 115
 116     while (datalen > INT_MAX) {
 117         if (!EVP_EncryptUpdate(ctx, NULL, &outlen, data, INT_MAX))
 118             return 0;
 119         data += INT_MAX;
 120         datalen -= INT_MAX;
 121     }
 122     return EVP_EncryptUpdate(ctx, NULL, &outlen, data, datalen);
 123 }
 124
 125 static int gmac_final(void *vmacctx, unsigned char *out, size_t *outl,
 126                       size_t outsize)
 127 {
 128     struct gmac_data_st *macctx = vmacctx;
 129     int hlen = 0;
 130
 131     if (!ossl_prov_is_running())
 132         return 0;
 133
 134     if (!EVP_EncryptFinal_ex(macctx->ctx, out, &hlen))
 135         return 0;
 136
 137     /* TODO(3.0) Use params */
 138     hlen = gmac_size();
 139     if (!EVP_CIPHER_CTX_ctrl(macctx->ctx, EVP_CTRL_AEAD_GET_TAG,
 140                              hlen, out))
 141         return 0;
 142
 143     *outl = hlen;
 144     return 1;
 145 }
 146
 147 static const OSSL_PARAM known_gettable_params[] = {
 148     OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL),
 149     OSSL_PARAM_END
 150 };
 151 static const OSSL_PARAM *gmac_gettable_params(void *provctx)
 152 {
 153     return known_gettable_params;
 154 }
 155
 156 static int gmac_get_params(OSSL_PARAM params[])
 157 {
 158     OSSL_PARAM *p;
 159
 160     if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_SIZE)) != NULL)
 161         return OSSL_PARAM_set_size_t(p, gmac_size());
 162
 163     return 1;
 164 }
 165
 166 static const OSSL_PARAM known_settable_ctx_params[] = {
 167     OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_CIPHER, NULL, 0),
 168     OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_PROPERTIES, NULL, 0),
 169     OSSL_PARAM_octet_string(OSSL_MAC_PARAM_KEY, NULL, 0),
 170     OSSL_PARAM_octet_string(OSSL_MAC_PARAM_IV, NULL, 0),
 171     OSSL_PARAM_END
 172 };
 173 static const OSSL_PARAM *gmac_settable_ctx_params(ossl_unused void *provctx)
 174 {
 175     return known_settable_ctx_params;
 176 }
 177
 178 /*
 179  * ALL parameters should be set before init().
 180  */
 181 static int gmac_set_ctx_params(void *vmacctx, const OSSL_PARAM params[])
 182 {
 183     struct gmac_data_st *macctx = vmacctx;
 184     EVP_CIPHER_CTX *ctx = macctx->ctx;
 185     OSSL_LIB_CTX *provctx = PROV_LIBCTX_OF(macctx->provctx);
 186     const OSSL_PARAM *p;
 187
 188    if (ctx == NULL
 189         || !ossl_prov_cipher_load_from_params(&macctx->cipher, params, provctx))
 190         return 0;
 191
 192     if (EVP_CIPHER_mode(ossl_prov_cipher_cipher(&macctx->cipher))
 193         != EVP_CIPH_GCM_MODE) {
 194         ERR_raise(ERR_LIB_PROV, EVP_R_CIPHER_NOT_GCM_MODE);
 195         return 0;
 196     }
 197     if (!EVP_EncryptInit_ex(ctx, ossl_prov_cipher_cipher(&macctx->cipher),
 198                             ossl_prov_cipher_engine(&macctx->cipher), NULL,
 199                             NULL))
 200         return 0;
 201
 202     if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_KEY)) != NULL) {
 203         if (p->data_type != OSSL_PARAM_OCTET_STRING)
 204             return 0;
 205
 206         if (p->data_size != (size_t)EVP_CIPHER_CTX_key_length(ctx)) {
 207             ERR_raise(ERR_LIB_PROV, EVP_R_INVALID_KEY_LENGTH);
 208             return 0;
 209         }
 210         if (!EVP_EncryptInit_ex(ctx, NULL, NULL, p->data, NULL))
 211             return 0;
 212     }
 213     if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_IV)) != NULL) {
 214         if (p->data_type != OSSL_PARAM_OCTET_STRING)
 215             return 0;
 216
 217         if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN,
 218                                  p->data_size, NULL)
 219             || !EVP_EncryptInit_ex(ctx, NULL, NULL, NULL, p->data))
 220             return 0;
 221     }
 222     return 1;
 223 }
 224
 225 const OSSL_DISPATCH ossl_gmac_functions[] = {
 226     { OSSL_FUNC_MAC_NEWCTX, (void (*)(void))gmac_new },
 227     { OSSL_FUNC_MAC_DUPCTX, (void (*)(void))gmac_dup },
 228     { OSSL_FUNC_MAC_FREECTX, (void (*)(void))gmac_free },
 229     { OSSL_FUNC_MAC_INIT, (void (*)(void))gmac_init },
 230     { OSSL_FUNC_MAC_UPDATE, (void (*)(void))gmac_update },
 231     { OSSL_FUNC_MAC_FINAL, (void (*)(void))gmac_final },
 232     { OSSL_FUNC_MAC_GETTABLE_PARAMS, (void (*)(void))gmac_gettable_params },
 233     { OSSL_FUNC_MAC_GET_PARAMS, (void (*)(void))gmac_get_params },
 234     { OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS,
 235       (void (*)(void))gmac_settable_ctx_params },
 236     { OSSL_FUNC_MAC_SET_CTX_PARAMS, (void (*)(void))gmac_set_ctx_params },
 237     { 0, NULL }
 238 };