providers/implementations/encode_decode/decode_pvk2key.c

   1 /*
   2  * Copyright 2020-2021 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 /*
  11  * low level APIs are deprecated for public use, but still ok for
  12  * internal use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include <string.h>
  17
  18 #include <openssl/core_dispatch.h>
  19 #include <openssl/core_names.h>
  20 #include <openssl/core_object.h>
  21 #include <openssl/crypto.h>
  22 #include <openssl/params.h>
  23 #include <openssl/err.h>
  24 #include <openssl/pem.h>         /* For public PVK functions */
  25 #include <openssl/x509.h>
  26 #include "internal/passphrase.h"
  27 #include "crypto/pem.h"          /* For internal PVK and "blob" headers */
  28 #include "crypto/rsa.h"
  29 #include "prov/bio.h"
  30 #include "prov/implementations.h"
  31 #include "endecoder_local.h"
  32
  33 struct pvk2key_ctx_st;            /* Forward declaration */
  34 typedef int check_key_fn(void *, struct pvk2key_ctx_st *ctx);
  35 typedef void adjust_key_fn(void *, struct pvk2key_ctx_st *ctx);
  36 typedef void *b2i_PVK_of_bio_pw_fn(BIO *in, pem_password_cb *cb, void *u,
  37                                    OSSL_LIB_CTX *libctx, const char *propq);
  38 typedef void free_key_fn(void *);
  39 struct keytype_desc_st {
  40     int type;                 /* EVP key type */
  41     const char *name;         /* Keytype */
  42     const OSSL_DISPATCH *fns; /* Keymgmt (to pilfer functions from) */
  43
  44     b2i_PVK_of_bio_pw_fn *read_private_key;
  45     adjust_key_fn *adjust_key;
  46     free_key_fn *free_key;
  47 };
  48
  49 static OSSL_FUNC_decoder_freectx_fn pvk2key_freectx;
  50 static OSSL_FUNC_decoder_decode_fn pvk2key_decode;
  51 static OSSL_FUNC_decoder_export_object_fn pvk2key_export_object;
  52
  53 /*
  54  * Context used for DER to key decoding.
  55  */
  56 struct pvk2key_ctx_st {
  57     PROV_CTX *provctx;
  58     const struct keytype_desc_st *desc;
  59 };
  60
  61 static struct pvk2key_ctx_st *
  62 pvk2key_newctx(void *provctx, const struct keytype_desc_st *desc)
  63 {
  64     struct pvk2key_ctx_st *ctx = OPENSSL_zalloc(sizeof(*ctx));
  65
  66     if (ctx != NULL) {
  67         ctx->provctx = provctx;
  68         ctx->desc = desc;
  69     }
  70     return ctx;
  71 }
  72
  73 static void pvk2key_freectx(void *vctx)
  74 {
  75     struct pvk2key_ctx_st *ctx = vctx;
  76
  77     OPENSSL_free(ctx);
  78 }
  79
  80 static int pvk2key_decode(void *vctx, OSSL_CORE_BIO *cin, int selection,
  81                          OSSL_CALLBACK *data_cb, void *data_cbarg,
  82                          OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg)
  83 {
  84     struct pvk2key_ctx_st *ctx = vctx;
  85     BIO *in = ossl_bio_new_from_core_bio(ctx->provctx, cin);
  86     void *key = NULL;
  87     int ok = 0;
  88
  89     if ((selection == 0
  90          || (selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
  91         && ctx->desc->read_private_key != NULL) {
  92         struct ossl_passphrase_data_st pwdata;
  93         int err, lib, reason;
  94
  95         memset(&pwdata, 0, sizeof(pwdata));
  96         if (!ossl_pw_set_ossl_passphrase_cb(&pwdata, pw_cb, pw_cbarg))
  97             goto end;
  98
  99         key = ctx->desc->read_private_key(in, ossl_pw_pem_password, &pwdata,
 100                                           PROV_LIBCTX_OF(ctx->provctx), NULL);
 101
 102         /*
 103          * Because the PVK API doesn't have a separate decrypt call, we need
 104          * to check the error queue for certain well known errors that are
 105          * considered fatal and which we pass through, while the rest gets
 106          * thrown away.
 107          */
 108         err = ERR_peek_last_error();
 109         lib = ERR_GET_LIB(err);
 110         reason = ERR_GET_REASON(err);
 111         if (lib == ERR_LIB_PEM
 112             && (reason == PEM_R_BAD_PASSWORD_READ
 113                 || reason == PEM_R_BAD_DECRYPT)) {
 114             ERR_clear_last_mark();
 115             goto end;
 116         }
 117
 118         if (selection != 0 && key == NULL)
 119             goto next;
 120     }
 121
 122     if (key != NULL && ctx->desc->adjust_key != NULL)
 123         ctx->desc->adjust_key(key, ctx);
 124
 125  next:
 126     /*
 127      * Indicated that we successfully decoded something, or not at all.
 128      * Ending up "empty handed" is not an error.
 129      */
 130     ok = 1;
 131
 132     /*
 133      * We free resources here so it's not held up during the callback, because
 134      * we know the process is recursive and the allocated chunks of memory
 135      * add up.
 136      */
 137     BIO_free(in);
 138     in = NULL;
 139
 140     if (key != NULL) {
 141         OSSL_PARAM params[4];
 142         int object_type = OSSL_OBJECT_PKEY;
 143
 144         params[0] =
 145             OSSL_PARAM_construct_int(OSSL_OBJECT_PARAM_TYPE, &object_type);
 146         params[1] =
 147             OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_TYPE,
 148                                              (char *)ctx->desc->name, 0);
 149         /* The address of the key becomes the octet string */
 150         params[2] =
 151             OSSL_PARAM_construct_octet_string(OSSL_OBJECT_PARAM_REFERENCE,
 152                                               &key, sizeof(key));
 153         params[3] = OSSL_PARAM_construct_end();
 154
 155         ok = data_cb(params, data_cbarg);
 156     }
 157
 158  end:
 159     BIO_free(in);
 160     ctx->desc->free_key(key);
 161
 162     return ok;
 163 }
 164
 165 static int pvk2key_export_object(void *vctx,
 166                                 const void *reference, size_t reference_sz,
 167                                 OSSL_CALLBACK *export_cb, void *export_cbarg)
 168 {
 169     struct pvk2key_ctx_st *ctx = vctx;
 170     OSSL_FUNC_keymgmt_export_fn *export =
 171         ossl_prov_get_keymgmt_export(ctx->desc->fns);
 172     void *keydata;
 173
 174     if (reference_sz == sizeof(keydata) && export != NULL) {
 175         /* The contents of the reference is the address to our object */
 176         keydata = *(void **)reference;
 177
 178         return export(keydata, OSSL_KEYMGMT_SELECT_ALL,
 179                       export_cb, export_cbarg);
 180     }
 181     return 0;
 182 }
 183
 184 /* ---------------------------------------------------------------------- */
 185
 186 #define dsa_private_key_bio     (b2i_PVK_of_bio_pw_fn *)b2i_DSA_PVK_bio_ex
 187 #define dsa_adjust              NULL
 188 #define dsa_free                (void (*)(void *))DSA_free
 189
 190 /* ---------------------------------------------------------------------- */
 191
 192 #define rsa_private_key_bio     (b2i_PVK_of_bio_pw_fn *)b2i_RSA_PVK_bio_ex
 193
 194 static void rsa_adjust(void *key, struct pvk2key_ctx_st *ctx)
 195 {
 196     ossl_rsa_set0_libctx(key, PROV_LIBCTX_OF(ctx->provctx));
 197 }
 198
 199 #define rsa_free                (void (*)(void *))RSA_free
 200
 201 /* ---------------------------------------------------------------------- */
 202
 203 #define IMPLEMENT_MS(KEYTYPE, keytype)                                  \
 204     static const struct keytype_desc_st                                 \
 205     pvk2##keytype##_desc = {                                            \
 206         EVP_PKEY_##KEYTYPE, #KEYTYPE,                                   \
 207         ossl_##keytype##_keymgmt_functions,                             \
 208         keytype##_private_key_bio,                                      \
 209         keytype##_adjust,                                               \
 210         keytype##_free                                                  \
 211     };                                                                  \
 212     static OSSL_FUNC_decoder_newctx_fn pvk2##keytype##_newctx;          \
 213     static void *pvk2##keytype##_newctx(void *provctx)                  \
 214     {                                                                   \
 215         return pvk2key_newctx(provctx, &pvk2##keytype##_desc);          \
 216     }                                                                   \
 217     const OSSL_DISPATCH                                                 \
 218     ossl_##pvk_to_##keytype##_decoder_functions[] = {                   \
 219         { OSSL_FUNC_DECODER_NEWCTX,                                     \
 220           (void (*)(void))pvk2##keytype##_newctx },                     \
 221         { OSSL_FUNC_DECODER_FREECTX,                                    \
 222           (void (*)(void))pvk2key_freectx },                            \
 223         { OSSL_FUNC_DECODER_DECODE,                                     \
 224           (void (*)(void))pvk2key_decode },                             \
 225         { OSSL_FUNC_DECODER_EXPORT_OBJECT,                              \
 226           (void (*)(void))pvk2key_export_object },                      \
 227         { 0, NULL }                                                     \
 228     }
 229
 230 #ifndef OPENSSL_NO_DSA
 231 IMPLEMENT_MS(DSA, dsa);
 232 #endif
 233 IMPLEMENT_MS(RSA, rsa);