providers/common/macs/hmac_prov.c

   1 /*
   2  * Copyright 2018 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/core_numbers.h>
  11 #include <openssl/core_names.h>
  12 #include <openssl/params.h>
  13 #include <openssl/engine.h>
  14 #include <openssl/evp.h>
  15 #include <openssl/hmac.h>
  16
  17 #include "internal/provider_algs.h"
  18 #include "internal/provider_ctx.h"
  19 #include "internal/provider_util.h"
  20
  21 /*
  22  * Forward declaration of everything implemented here.  This is not strictly
  23  * necessary for the compiler, but provides an assurance that the signatures
  24  * of the functions in the dispatch table are correct.
  25  */
  26 static OSSL_OP_mac_newctx_fn hmac_new;
  27 static OSSL_OP_mac_dupctx_fn hmac_dup;
  28 static OSSL_OP_mac_freectx_fn hmac_free;
  29 static OSSL_OP_mac_gettable_ctx_params_fn hmac_gettable_ctx_params;
  30 static OSSL_OP_mac_get_ctx_params_fn hmac_get_ctx_params;
  31 static OSSL_OP_mac_settable_ctx_params_fn hmac_settable_ctx_params;
  32 static OSSL_OP_mac_set_ctx_params_fn hmac_set_ctx_params;
  33 static OSSL_OP_mac_init_fn hmac_init;
  34 static OSSL_OP_mac_update_fn hmac_update;
  35 static OSSL_OP_mac_final_fn hmac_final;
  36
  37 /* local HMAC context structure */
  38
  39 /* typedef EVP_MAC_IMPL */
  40 struct hmac_data_st {
  41     void *provctx;
  42     HMAC_CTX *ctx;               /* HMAC context */
  43     PROV_DIGEST digest;
  44 };
  45
  46 static size_t hmac_size(void *vmacctx);
  47
  48 static void *hmac_new(void *provctx)
  49 {
  50     struct hmac_data_st *macctx;
  51
  52     if ((macctx = OPENSSL_zalloc(sizeof(*macctx))) == NULL
  53         || (macctx->ctx = HMAC_CTX_new()) == NULL) {
  54         OPENSSL_free(macctx);
  55         return NULL;
  56     }
  57     /* TODO(3.0) Should we do something more with that context? */
  58     macctx->provctx = provctx;
  59
  60     return macctx;
  61 }
  62
  63 static void hmac_free(void *vmacctx)
  64 {
  65     struct hmac_data_st *macctx = vmacctx;
  66
  67     if (macctx != NULL) {
  68         HMAC_CTX_free(macctx->ctx);
  69         ossl_prov_digest_reset(&macctx->digest);
  70         OPENSSL_free(macctx);
  71     }
  72 }
  73
  74 static void *hmac_dup(void *vsrc)
  75 {
  76     struct hmac_data_st *src = vsrc;
  77     struct hmac_data_st *dst = hmac_new(src->provctx);
  78
  79     if (dst == NULL)
  80         return NULL;
  81
  82     if (!HMAC_CTX_copy(dst->ctx, src->ctx)
  83         || !ossl_prov_digest_copy(&dst->digest, &src->digest)) {
  84         hmac_free(dst);
  85         return NULL;
  86     }
  87     return dst;
  88 }
  89
  90 static size_t hmac_size(void *vmacctx)
  91 {
  92     struct hmac_data_st *macctx = vmacctx;
  93
  94     return HMAC_size(macctx->ctx);
  95 }
  96
  97 static int hmac_init(void *vmacctx)
  98 {
  99     struct hmac_data_st *macctx = vmacctx;
 100     const EVP_MD *digest = ossl_prov_digest_md(&macctx->digest);
 101     int rv = 1;
 102
 103     /* HMAC_Init_ex doesn't tolerate all zero params, so we must be careful */
 104     if (digest != NULL)
 105         rv = HMAC_Init_ex(macctx->ctx, NULL, 0, digest,
 106                           ossl_prov_digest_engine(&macctx->digest));
 107     ossl_prov_digest_reset(&macctx->digest);
 108     return rv;
 109 }
 110
 111 static int hmac_update(void *vmacctx, const unsigned char *data,
 112                        size_t datalen)
 113 {
 114     struct hmac_data_st *macctx = vmacctx;
 115
 116     return HMAC_Update(macctx->ctx, data, datalen);
 117 }
 118
 119 static int hmac_final(void *vmacctx, unsigned char *out, size_t *outl,
 120                       size_t outsize)
 121 {
 122     unsigned int hlen;
 123     struct hmac_data_st *macctx = vmacctx;
 124
 125     if (!HMAC_Final(macctx->ctx, out, &hlen))
 126         return 0;
 127     if (outl != NULL)
 128         *outl = hlen;
 129     return 1;
 130 }
 131
 132 static const OSSL_PARAM known_gettable_ctx_params[] = {
 133     OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL),
 134     OSSL_PARAM_END
 135 };
 136 static const OSSL_PARAM *hmac_gettable_ctx_params(void)
 137 {
 138     return known_gettable_ctx_params;
 139 }
 140
 141 static int hmac_get_ctx_params(void *vmacctx, OSSL_PARAM params[])
 142 {
 143     OSSL_PARAM *p;
 144
 145     if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_SIZE)) != NULL)
 146         return OSSL_PARAM_set_size_t(p, hmac_size(vmacctx));
 147
 148     return 1;
 149 }
 150
 151 static const OSSL_PARAM known_settable_ctx_params[] = {
 152     OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_DIGEST, NULL, 0),
 153     OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_ENGINE, NULL, 0),
 154     OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_PROPERTIES, NULL, 0),
 155     OSSL_PARAM_octet_string(OSSL_MAC_PARAM_KEY, NULL, 0),
 156     OSSL_PARAM_int(OSSL_MAC_PARAM_FLAGS, NULL),
 157     OSSL_PARAM_END
 158 };
 159 static const OSSL_PARAM *hmac_settable_ctx_params(void)
 160 {
 161     return known_settable_ctx_params;
 162 }
 163
 164 /*
 165  * ALL parameters should be set before init().
 166  */
 167 static int hmac_set_ctx_params(void *vmacctx, const OSSL_PARAM params[])
 168 {
 169     struct hmac_data_st *macctx = vmacctx;
 170     OPENSSL_CTX *ctx = PROV_LIBRARY_CONTEXT_OF(macctx->provctx);
 171     const OSSL_PARAM *p;
 172
 173     if (!ossl_prov_digest_load_from_params(&macctx->digest, params, ctx))
 174         return 0;
 175
 176     /* TODO(3.0) formalize the meaning of "flags", perhaps as other params */
 177     if ((p = OSSL_PARAM_locate_const(params,
 178                                      OSSL_MAC_PARAM_FLAGS)) != NULL) {
 179         int flags = 0;
 180
 181         if (!OSSL_PARAM_get_int(p, &flags))
 182             return 0;
 183         HMAC_CTX_set_flags(macctx->ctx, flags);
 184     }
 185     if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_KEY)) != NULL) {
 186         if (p->data_type != OSSL_PARAM_OCTET_STRING)
 187             return 0;
 188
 189         if (!HMAC_Init_ex(macctx->ctx, p->data, p->data_size,
 190                           ossl_prov_digest_md(&macctx->digest),
 191                           NULL /* ENGINE */))
 192             return 0;
 193
 194         ossl_prov_digest_reset(&macctx->digest);
 195     }
 196     return 1;
 197 }
 198
 199 const OSSL_DISPATCH hmac_functions[] = {
 200     { OSSL_FUNC_MAC_NEWCTX, (void (*)(void))hmac_new },
 201     { OSSL_FUNC_MAC_DUPCTX, (void (*)(void))hmac_dup },
 202     { OSSL_FUNC_MAC_FREECTX, (void (*)(void))hmac_free },
 203     { OSSL_FUNC_MAC_INIT, (void (*)(void))hmac_init },
 204     { OSSL_FUNC_MAC_UPDATE, (void (*)(void))hmac_update },
 205     { OSSL_FUNC_MAC_FINAL, (void (*)(void))hmac_final },
 206     { OSSL_FUNC_MAC_GETTABLE_CTX_PARAMS,
 207       (void (*)(void))hmac_gettable_ctx_params },
 208     { OSSL_FUNC_MAC_GET_CTX_PARAMS, (void (*)(void))hmac_get_ctx_params },
 209     { OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS,
 210       (void (*)(void))hmac_settable_ctx_params },
 211     { OSSL_FUNC_MAC_SET_CTX_PARAMS, (void (*)(void))hmac_set_ctx_params },
 212     { 0, NULL }
 213 };