providers/implementations/macs/gmac_prov.c

   1 /*
   2  * Copyright 2018-2022 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 <stdlib.h>
  11 #include <openssl/core_dispatch.h>
  12 #include <openssl/core_names.h>
  13 #include <openssl/params.h>
  14 #include <openssl/evp.h>
  15 #include <openssl/err.h>
  16 #include <openssl/proverr.h>
  17
  18 #include "prov/implementations.h"
  19 #include "prov/provider_ctx.h"
  20 #include "prov/provider_util.h"
  21 #include "prov/providercommon.h"
  22
  23 /*
  24  * Forward declaration of everything implemented here.  This is not strictly
  25  * necessary for the compiler, but provides an assurance that the signatures
  26  * of the functions in the dispatch table are correct.
  27  */
  28 static OSSL_FUNC_mac_newctx_fn gmac_new;
  29 static OSSL_FUNC_mac_dupctx_fn gmac_dup;
  30 static OSSL_FUNC_mac_freectx_fn gmac_free;
  31 static OSSL_FUNC_mac_gettable_params_fn gmac_gettable_params;
  32 static OSSL_FUNC_mac_get_params_fn gmac_get_params;
  33 static OSSL_FUNC_mac_settable_ctx_params_fn gmac_settable_ctx_params;
  34 static OSSL_FUNC_mac_set_ctx_params_fn gmac_set_ctx_params;
  35 static OSSL_FUNC_mac_init_fn gmac_init;
  36 static OSSL_FUNC_mac_update_fn gmac_update;
  37 static OSSL_FUNC_mac_final_fn gmac_final;
  38
  39 /* local GMAC pkey structure */
  40
  41 struct gmac_data_st {
  42     void *provctx;
  43     EVP_CIPHER_CTX *ctx;         /* Cipher context */
  44     PROV_CIPHER cipher;
  45 };
  46
  47 static void gmac_free(void *vmacctx)
  48 {
  49     struct gmac_data_st *macctx = vmacctx;
  50
  51     if (macctx != NULL) {
  52         EVP_CIPHER_CTX_free(macctx->ctx);
  53         ossl_prov_cipher_reset(&macctx->cipher);
  54         OPENSSL_free(macctx);
  55     }
  56 }
  57
  58 static void *gmac_new(void *provctx)
  59 {
  60     struct gmac_data_st *macctx;
  61
  62     if (!ossl_prov_is_running())
  63         return NULL;
  64
  65     if ((macctx = OPENSSL_zalloc(sizeof(*macctx))) == NULL
  66         || (macctx->ctx = EVP_CIPHER_CTX_new()) == NULL) {
  67         gmac_free(macctx);
  68         return NULL;
  69     }
  70     macctx->provctx = provctx;
  71
  72     return macctx;
  73 }
  74
  75 static void *gmac_dup(void *vsrc)
  76 {
  77     struct gmac_data_st *src = vsrc;
  78     struct gmac_data_st *dst;
  79
  80     if (!ossl_prov_is_running())
  81         return NULL;
  82
  83     dst = gmac_new(src->provctx);
  84     if (dst == NULL)
  85         return NULL;
  86
  87     if (!EVP_CIPHER_CTX_copy(dst->ctx, src->ctx)
  88         || !ossl_prov_cipher_copy(&dst->cipher, &src->cipher)) {
  89         gmac_free(dst);
  90         return NULL;
  91     }
  92     return dst;
  93 }
  94
  95 static size_t gmac_size(void)
  96 {
  97     return EVP_GCM_TLS_TAG_LEN;
  98 }
  99
 100 static int gmac_setkey(struct gmac_data_st *macctx,
 101                        const unsigned char *key, size_t keylen)
 102 {
 103     EVP_CIPHER_CTX *ctx = macctx->ctx;
 104
 105     if (keylen != (size_t)EVP_CIPHER_CTX_get_key_length(ctx)) {
 106         ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
 107         return 0;
 108     }
 109     if (!EVP_EncryptInit_ex(ctx, NULL, NULL, key, NULL))
 110         return 0;
 111     return 1;
 112 }
 113
 114 static int gmac_init(void *vmacctx, const unsigned char *key,
 115                      size_t keylen, const OSSL_PARAM params[])
 116 {
 117     struct gmac_data_st *macctx = vmacctx;
 118
 119     if (!ossl_prov_is_running() || !gmac_set_ctx_params(macctx, params))
 120         return 0;
 121     if (key != NULL)
 122         return gmac_setkey(macctx, key, keylen);
 123     return EVP_EncryptInit_ex(macctx->ctx, NULL, NULL, NULL, NULL);
 124 }
 125
 126 static int gmac_update(void *vmacctx, const unsigned char *data,
 127                        size_t datalen)
 128 {
 129     struct gmac_data_st *macctx = vmacctx;
 130     EVP_CIPHER_CTX *ctx = macctx->ctx;
 131     int outlen;
 132
 133     if (datalen == 0)
 134         return 1;
 135
 136     while (datalen > INT_MAX) {
 137         if (!EVP_EncryptUpdate(ctx, NULL, &outlen, data, INT_MAX))
 138             return 0;
 139         data += INT_MAX;
 140         datalen -= INT_MAX;
 141     }
 142     return EVP_EncryptUpdate(ctx, NULL, &outlen, data, datalen);
 143 }
 144
 145 static int gmac_final(void *vmacctx, unsigned char *out, size_t *outl,
 146                       size_t outsize)
 147 {
 148     OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
 149     struct gmac_data_st *macctx = vmacctx;
 150     int hlen = 0;
 151
 152     if (!ossl_prov_is_running())
 153         return 0;
 154
 155     if (!EVP_EncryptFinal_ex(macctx->ctx, out, &hlen))
 156         return 0;
 157
 158     hlen = gmac_size();
 159     params[0] = OSSL_PARAM_construct_octet_string(OSSL_CIPHER_PARAM_AEAD_TAG,
 160                                                   out, (size_t)hlen);
 161     if (!EVP_CIPHER_CTX_get_params(macctx->ctx, params))
 162         return 0;
 163
 164     *outl = hlen;
 165     return 1;
 166 }
 167
 168 static const OSSL_PARAM known_gettable_params[] = {
 169     OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL),
 170     OSSL_PARAM_END
 171 };
 172 static const OSSL_PARAM *gmac_gettable_params(void *provctx)
 173 {
 174     return known_gettable_params;
 175 }
 176
 177 static int gmac_get_params(OSSL_PARAM params[])
 178 {
 179     OSSL_PARAM *p;
 180
 181     if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_SIZE)) != NULL)
 182         return OSSL_PARAM_set_size_t(p, gmac_size());
 183
 184     return 1;
 185 }
 186
 187 static const OSSL_PARAM known_settable_ctx_params[] = {
 188     OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_CIPHER, NULL, 0),
 189     OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_PROPERTIES, NULL, 0),
 190     OSSL_PARAM_octet_string(OSSL_MAC_PARAM_KEY, NULL, 0),
 191     OSSL_PARAM_octet_string(OSSL_MAC_PARAM_IV, NULL, 0),
 192     OSSL_PARAM_END
 193 };
 194 static const OSSL_PARAM *gmac_settable_ctx_params(ossl_unused void *ctx,
 195                                                   ossl_unused void *provctx)
 196 {
 197     return known_settable_ctx_params;
 198 }
 199
 200 /*
 201  * ALL parameters should be set before init().
 202  */
 203 static int gmac_set_ctx_params(void *vmacctx, const OSSL_PARAM params[])
 204 {
 205     struct gmac_data_st *macctx = vmacctx;
 206     EVP_CIPHER_CTX *ctx = macctx->ctx;
 207     OSSL_LIB_CTX *provctx = PROV_LIBCTX_OF(macctx->provctx);
 208     const OSSL_PARAM *p;
 209
 210     if (params == NULL)
 211         return 1;
 212     if (ctx == NULL)
 213         return 0;
 214
 215     if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_CIPHER)) != NULL) {
 216         if (!ossl_prov_cipher_load_from_params(&macctx->cipher, params, provctx))
 217             return 0;
 218         if (EVP_CIPHER_get_mode(ossl_prov_cipher_cipher(&macctx->cipher))
 219             != EVP_CIPH_GCM_MODE) {
 220             ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_MODE);
 221             return 0;
 222         }
 223         if (!EVP_EncryptInit_ex(ctx, ossl_prov_cipher_cipher(&macctx->cipher),
 224                                 ossl_prov_cipher_engine(&macctx->cipher), NULL,
 225                                 NULL))
 226             return 0;
 227     }
 228
 229     if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_KEY)) != NULL)
 230         if (p->data_type != OSSL_PARAM_OCTET_STRING
 231                 || !gmac_setkey(macctx, p->data, p->data_size))
 232             return 0;
 233
 234     if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_IV)) != NULL) {
 235         if (p->data_type != OSSL_PARAM_OCTET_STRING)
 236             return 0;
 237
 238         if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN,
 239                                  p->data_size, NULL)
 240             || !EVP_EncryptInit_ex(ctx, NULL, NULL, NULL, p->data))
 241             return 0;
 242     }
 243     return 1;
 244 }
 245
 246 const OSSL_DISPATCH ossl_gmac_functions[] = {
 247     { OSSL_FUNC_MAC_NEWCTX, (void (*)(void))gmac_new },
 248     { OSSL_FUNC_MAC_DUPCTX, (void (*)(void))gmac_dup },
 249     { OSSL_FUNC_MAC_FREECTX, (void (*)(void))gmac_free },
 250     { OSSL_FUNC_MAC_INIT, (void (*)(void))gmac_init },
 251     { OSSL_FUNC_MAC_UPDATE, (void (*)(void))gmac_update },
 252     { OSSL_FUNC_MAC_FINAL, (void (*)(void))gmac_final },
 253     { OSSL_FUNC_MAC_GETTABLE_PARAMS, (void (*)(void))gmac_gettable_params },
 254     { OSSL_FUNC_MAC_GET_PARAMS, (void (*)(void))gmac_get_params },
 255     { OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS,
 256       (void (*)(void))gmac_settable_ctx_params },
 257     { OSSL_FUNC_MAC_SET_CTX_PARAMS, (void (*)(void))gmac_set_ctx_params },
 258     { 0, NULL }
 259 };