crypto/evp/evp_utils.c

   1 /*
   2  * Copyright 2019 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 /* Internal EVP utility functions */
  11
  12 #include <openssl/core.h>
  13 #include <openssl/evp.h>
  14 #include <openssl/err.h>
  15 #include <openssl/asn1.h>        /* evp_locl.h needs it */
  16 #include <openssl/safestack.h>   /* evp_locl.h needs it */
  17 #include "internal/evp_int.h"    /* evp_locl.h needs it */
  18 #include "evp_locl.h"
  19
  20 /*
  21  * EVP_CTRL_RET_UNSUPPORTED = -1 is the returned value from any ctrl function
  22  * where the control command isn't supported, and an alternative code path
  23  * may be chosen.
  24  * Since these functions are used to implement ctrl functionality, we
  25  * use the same value, and other callers will have to compensate.
  26  */
  27 #define PARAM_CHECK(obj, func, errfunc)                                        \
  28     if (obj->prov == NULL)                                                     \
  29         return EVP_CTRL_RET_UNSUPPORTED;                                       \
  30     if (obj->func == NULL) {                                                   \
  31         errfunc();                                                             \
  32         return 0;                                                              \
  33     }
  34
  35 #define PARAM_FUNC(name, func, type, err)                                      \
  36 int name (const type *obj, OSSL_PARAM params[])                                \
  37 {                                                                              \
  38     PARAM_CHECK(obj, func, err)                                                \
  39     return obj->func(params);                                                  \
  40 }
  41
  42 #define PARAM_CTX_FUNC(name, func, type, err)                                  \
  43 int name (const type *obj, void *provctx, OSSL_PARAM params[])                 \
  44 {                                                                              \
  45     PARAM_CHECK(obj, func, err)                                                \
  46     return obj->func(provctx, params);                                         \
  47 }
  48
  49 #define PARAM_FUNCTIONS(type,                                                  \
  50                         getname, getfunc,                                      \
  51                         getctxname, getctxfunc,                                \
  52                         setctxname, setctxfunc)                                \
  53     PARAM_FUNC(getname, getfunc, type, geterr)                                 \
  54     PARAM_CTX_FUNC(getctxname, getctxfunc, type, geterr)                       \
  55     PARAM_CTX_FUNC(setctxname, setctxfunc, type, seterr)
  56
  57 /*
  58  * These error functions are a workaround for the error scripts, which
  59  * currently require that XXXerr method appears inside a function (not a macro).
  60  */
  61 static void geterr(void)
  62 {
  63     EVPerr(0, EVP_R_CANNOT_GET_PARAMETERS);
  64 }
  65
  66 static void seterr(void)
  67 {
  68     EVPerr(0, EVP_R_CANNOT_SET_PARAMETERS);
  69 }
  70
  71 PARAM_FUNCTIONS(EVP_CIPHER,
  72                 evp_do_ciph_getparams, get_params,
  73                 evp_do_ciph_ctx_getparams, get_ctx_params,
  74                 evp_do_ciph_ctx_setparams, set_ctx_params)
  75
  76 PARAM_FUNCTIONS(EVP_MD,
  77                 evp_do_md_getparams, get_params,
  78                 evp_do_md_ctx_getparams, get_ctx_params,
  79                 evp_do_md_ctx_setparams, set_ctx_params)