providers/implementations/encode_decode/decode_msblob2key.c

   1 /*
   2  * Copyright 2020-2022 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 /*
  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/pem.h>         /* For public PVK functions */
  24 #include <openssl/x509.h>
  25 #include <openssl/err.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 msblob2key_ctx_st;            /* Forward declaration */
  34 typedef void *b2i_of_void_fn(const unsigned char **in, unsigned int bitlen,
  35                              int ispub);
  36 typedef void adjust_key_fn(void *, struct msblob2key_ctx_st *ctx);
  37 typedef void free_key_fn(void *);
  38 struct keytype_desc_st {
  39     int type;                 /* EVP key type */
  40     const char *name;         /* Keytype */
  41     const OSSL_DISPATCH *fns; /* Keymgmt (to pilfer functions from) */
  42
  43     b2i_of_void_fn *read_private_key;
  44     b2i_of_void_fn *read_public_key;
  45     adjust_key_fn *adjust_key;
  46     free_key_fn *free_key;
  47 };
  48
  49 static OSSL_FUNC_decoder_freectx_fn msblob2key_freectx;
  50 static OSSL_FUNC_decoder_decode_fn msblob2key_decode;
  51 static OSSL_FUNC_decoder_export_object_fn msblob2key_export_object;
  52
  53 /*
  54  * Context used for DER to key decoding.
  55  */
  56 struct msblob2key_ctx_st {
  57     PROV_CTX *provctx;
  58     const struct keytype_desc_st *desc;
  59     /* The selection that is passed to msblob2key_decode() */
  60     int selection;
  61 };
  62
  63 static struct msblob2key_ctx_st *
  64 msblob2key_newctx(void *provctx, const struct keytype_desc_st *desc)
  65 {
  66     struct msblob2key_ctx_st *ctx = OPENSSL_zalloc(sizeof(*ctx));
  67
  68     if (ctx != NULL) {
  69         ctx->provctx = provctx;
  70         ctx->desc = desc;
  71     }
  72     return ctx;
  73 }
  74
  75 static void msblob2key_freectx(void *vctx)
  76 {
  77     struct msblob2key_ctx_st *ctx = vctx;
  78
  79     OPENSSL_free(ctx);
  80 }
  81
  82 static int msblob2key_does_selection(void *provctx, int selection)
  83 {
  84     if (selection == 0)
  85         return 1;
  86
  87     if ((selection & (OSSL_KEYMGMT_SELECT_PRIVATE_KEY
  88                       | OSSL_KEYMGMT_SELECT_PUBLIC_KEY))  != 0)
  89         return 1;
  90
  91     return 0;
  92 }
  93
  94 static int msblob2key_decode(void *vctx, OSSL_CORE_BIO *cin, int selection,
  95                              OSSL_CALLBACK *data_cb, void *data_cbarg,
  96                              OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg)
  97 {
  98     struct msblob2key_ctx_st *ctx = vctx;
  99     BIO *in = ossl_bio_new_from_core_bio(ctx->provctx, cin);
 100     const unsigned char *p;
 101     unsigned char hdr_buf[16], *buf = NULL;
 102     unsigned int bitlen, magic, length;
 103     int isdss = -1;
 104     int ispub = -1;
 105     void *key = NULL;
 106     int ok = 0;
 107
 108     if (in == NULL)
 109         return 0;
 110
 111     if (BIO_read(in, hdr_buf, 16) != 16) {
 112         ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
 113         goto next;
 114     }
 115     ERR_set_mark();
 116     p = hdr_buf;
 117     ok = ossl_do_blob_header(&p, 16, &magic, &bitlen, &isdss, &ispub) > 0;
 118     ERR_pop_to_mark();
 119     if (!ok)
 120         goto next;
 121
 122     ctx->selection = selection;
 123     ok = 0;                      /* Assume that we fail */
 124
 125     if ((isdss && ctx->desc->type != EVP_PKEY_DSA)
 126         || (!isdss && ctx->desc->type != EVP_PKEY_RSA))
 127         goto next;
 128
 129     length = ossl_blob_length(bitlen, isdss, ispub);
 130     if (length > BLOB_MAX_LENGTH) {
 131         ERR_raise(ERR_LIB_PEM, PEM_R_HEADER_TOO_LONG);
 132         goto next;
 133     }
 134     buf = OPENSSL_malloc(length);
 135     if (buf == NULL)
 136         goto end;
 137     p = buf;
 138     if (BIO_read(in, buf, length) != (int)length) {
 139         ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
 140         goto next;
 141     }
 142
 143     if ((selection == 0
 144          || (selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
 145         && !ispub
 146         && ctx->desc->read_private_key != NULL) {
 147         struct ossl_passphrase_data_st pwdata;
 148
 149         memset(&pwdata, 0, sizeof(pwdata));
 150         if (!ossl_pw_set_ossl_passphrase_cb(&pwdata, pw_cb, pw_cbarg))
 151             goto end;
 152         p = buf;
 153         key = ctx->desc->read_private_key(&p, bitlen, ispub);
 154         if (selection != 0 && key == NULL)
 155             goto next;
 156     }
 157     if (key == NULL && (selection == 0
 158          || (selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
 159         && ispub
 160         && ctx->desc->read_public_key != NULL) {
 161         p = buf;
 162         key = ctx->desc->read_public_key(&p, bitlen, ispub);
 163         if (selection != 0 && key == NULL)
 164             goto next;
 165     }
 166
 167     if (key != NULL && ctx->desc->adjust_key != NULL)
 168         ctx->desc->adjust_key(key, ctx);
 169
 170  next:
 171     /*
 172      * Indicated that we successfully decoded something, or not at all.
 173      * Ending up "empty handed" is not an error.
 174      */
 175     ok = 1;
 176
 177     /*
 178      * We free resources here so it's not held up during the callback, because
 179      * we know the process is recursive and the allocated chunks of memory
 180      * add up.
 181      */
 182     OPENSSL_free(buf);
 183     BIO_free(in);
 184     buf = NULL;
 185     in = NULL;
 186
 187     if (key != NULL) {
 188         OSSL_PARAM params[4];
 189         int object_type = OSSL_OBJECT_PKEY;
 190
 191         params[0] =
 192             OSSL_PARAM_construct_int(OSSL_OBJECT_PARAM_TYPE, &object_type);
 193         params[1] =
 194             OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_TYPE,
 195                                              (char *)ctx->desc->name, 0);
 196         /* The address of the key becomes the octet string */
 197         params[2] =
 198             OSSL_PARAM_construct_octet_string(OSSL_OBJECT_PARAM_REFERENCE,
 199                                               &key, sizeof(key));
 200         params[3] = OSSL_PARAM_construct_end();
 201
 202         ok = data_cb(params, data_cbarg);
 203     }
 204
 205  end:
 206     BIO_free(in);
 207     OPENSSL_free(buf);
 208     ctx->desc->free_key(key);
 209
 210     return ok;
 211 }
 212
 213 static int
 214 msblob2key_export_object(void *vctx,
 215                          const void *reference, size_t reference_sz,
 216                          OSSL_CALLBACK *export_cb, void *export_cbarg)
 217 {
 218     struct msblob2key_ctx_st *ctx = vctx;
 219     OSSL_FUNC_keymgmt_export_fn *export =
 220         ossl_prov_get_keymgmt_export(ctx->desc->fns);
 221     void *keydata;
 222
 223     if (reference_sz == sizeof(keydata) && export != NULL) {
 224         int selection = ctx->selection;
 225
 226         if (selection == 0)
 227             selection = OSSL_KEYMGMT_SELECT_ALL;
 228         /* The contents of the reference is the address to our object */
 229         keydata = *(void **)reference;
 230
 231         return export(keydata, selection, export_cb, export_cbarg);
 232     }
 233     return 0;
 234 }
 235
 236 /* ---------------------------------------------------------------------- */
 237
 238 #define dsa_decode_private_key  (b2i_of_void_fn *)ossl_b2i_DSA_after_header
 239 #define dsa_decode_public_key   (b2i_of_void_fn *)ossl_b2i_DSA_after_header
 240 #define dsa_adjust              NULL
 241 #define dsa_free                (void (*)(void *))DSA_free
 242
 243 /* ---------------------------------------------------------------------- */
 244
 245 #define rsa_decode_private_key  (b2i_of_void_fn *)ossl_b2i_RSA_after_header
 246 #define rsa_decode_public_key   (b2i_of_void_fn *)ossl_b2i_RSA_after_header
 247
 248 static void rsa_adjust(void *key, struct msblob2key_ctx_st *ctx)
 249 {
 250     ossl_rsa_set0_libctx(key, PROV_LIBCTX_OF(ctx->provctx));
 251 }
 252
 253 #define rsa_free                        (void (*)(void *))RSA_free
 254
 255 /* ---------------------------------------------------------------------- */
 256
 257 #define IMPLEMENT_MSBLOB(KEYTYPE, keytype)                              \
 258     static const struct keytype_desc_st mstype##2##keytype##_desc = {   \
 259         EVP_PKEY_##KEYTYPE, #KEYTYPE,                                   \
 260         ossl_##keytype##_keymgmt_functions,                             \
 261         keytype##_decode_private_key,                                   \
 262         keytype##_decode_public_key,                                    \
 263         keytype##_adjust,                                               \
 264         keytype##_free                                                  \
 265     };                                                                  \
 266     static OSSL_FUNC_decoder_newctx_fn msblob2##keytype##_newctx;       \
 267     static void *msblob2##keytype##_newctx(void *provctx)               \
 268     {                                                                   \
 269         return msblob2key_newctx(provctx, &mstype##2##keytype##_desc);  \
 270     }                                                                   \
 271     const OSSL_DISPATCH                                                 \
 272     ossl_msblob_to_##keytype##_decoder_functions[] = {                  \
 273         { OSSL_FUNC_DECODER_NEWCTX,                                     \
 274           (void (*)(void))msblob2##keytype##_newctx },                  \
 275         { OSSL_FUNC_DECODER_FREECTX,                                    \
 276           (void (*)(void))msblob2key_freectx },                         \
 277         { OSSL_FUNC_DECODER_DOES_SELECTION,                             \
 278           (void (*)(void))msblob2key_does_selection },                  \
 279         { OSSL_FUNC_DECODER_DECODE,                                     \
 280           (void (*)(void))msblob2key_decode },                          \
 281         { OSSL_FUNC_DECODER_EXPORT_OBJECT,                              \
 282           (void (*)(void))msblob2key_export_object },                   \
 283         OSSL_DISPATCH_END                                               \
 284     }
 285
 286 #ifndef OPENSSL_NO_DSA
 287 IMPLEMENT_MSBLOB(DSA, dsa);
 288 #endif
 289 IMPLEMENT_MSBLOB(RSA, rsa);