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_decode(void *vctx, OSSL_CORE_BIO *cin, int selection,
  83                              OSSL_CALLBACK *data_cb, void *data_cbarg,
  84                              OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg)
  85 {
  86     struct msblob2key_ctx_st *ctx = vctx;
  87     BIO *in = ossl_bio_new_from_core_bio(ctx->provctx, cin);
  88     const unsigned char *p;
  89     unsigned char hdr_buf[16], *buf = NULL;
  90     unsigned int bitlen, magic, length;
  91     int isdss = -1;
  92     int ispub = -1;
  93     void *key = NULL;
  94     int ok = 0;
  95
  96     if (in == NULL)
  97         return 0;
  98
  99     if (BIO_read(in, hdr_buf, 16) != 16) {
 100         ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
 101         goto next;
 102     }
 103     ERR_set_mark();
 104     p = hdr_buf;
 105     ok = ossl_do_blob_header(&p, 16, &magic, &bitlen, &isdss, &ispub) > 0;
 106     ERR_pop_to_mark();
 107     if (!ok)
 108         goto next;
 109
 110     ctx->selection = selection;
 111     ok = 0;                      /* Assume that we fail */
 112
 113     if ((isdss && ctx->desc->type != EVP_PKEY_DSA)
 114         || (!isdss && ctx->desc->type != EVP_PKEY_RSA))
 115         goto next;
 116
 117     length = ossl_blob_length(bitlen, isdss, ispub);
 118     if (length > BLOB_MAX_LENGTH) {
 119         ERR_raise(ERR_LIB_PEM, PEM_R_HEADER_TOO_LONG);
 120         goto next;
 121     }
 122     buf = OPENSSL_malloc(length);
 123     if (buf == NULL)
 124         goto end;
 125     p = buf;
 126     if (BIO_read(in, buf, length) != (int)length) {
 127         ERR_raise(ERR_LIB_PEM, PEM_R_KEYBLOB_TOO_SHORT);
 128         goto next;
 129     }
 130
 131     if ((selection == 0
 132          || (selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
 133         && !ispub
 134         && ctx->desc->read_private_key != NULL) {
 135         struct ossl_passphrase_data_st pwdata;
 136
 137         memset(&pwdata, 0, sizeof(pwdata));
 138         if (!ossl_pw_set_ossl_passphrase_cb(&pwdata, pw_cb, pw_cbarg))
 139             goto end;
 140         p = buf;
 141         key = ctx->desc->read_private_key(&p, bitlen, ispub);
 142         if (selection != 0 && key == NULL)
 143             goto next;
 144     }
 145     if (key == NULL && (selection == 0
 146          || (selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
 147         && ispub
 148         && ctx->desc->read_public_key != NULL) {
 149         p = buf;
 150         key = ctx->desc->read_public_key(&p, bitlen, ispub);
 151         if (selection != 0 && key == NULL)
 152             goto next;
 153     }
 154
 155     if (key != NULL && ctx->desc->adjust_key != NULL)
 156         ctx->desc->adjust_key(key, ctx);
 157
 158  next:
 159     /*
 160      * Indicated that we successfully decoded something, or not at all.
 161      * Ending up "empty handed" is not an error.
 162      */
 163     ok = 1;
 164
 165     /*
 166      * We free resources here so it's not held up during the callback, because
 167      * we know the process is recursive and the allocated chunks of memory
 168      * add up.
 169      */
 170     OPENSSL_free(buf);
 171     BIO_free(in);
 172     buf = NULL;
 173     in = NULL;
 174
 175     if (key != NULL) {
 176         OSSL_PARAM params[4];
 177         int object_type = OSSL_OBJECT_PKEY;
 178
 179         params[0] =
 180             OSSL_PARAM_construct_int(OSSL_OBJECT_PARAM_TYPE, &object_type);
 181         params[1] =
 182             OSSL_PARAM_construct_utf8_string(OSSL_OBJECT_PARAM_DATA_TYPE,
 183                                              (char *)ctx->desc->name, 0);
 184         /* The address of the key becomes the octet string */
 185         params[2] =
 186             OSSL_PARAM_construct_octet_string(OSSL_OBJECT_PARAM_REFERENCE,
 187                                               &key, sizeof(key));
 188         params[3] = OSSL_PARAM_construct_end();
 189
 190         ok = data_cb(params, data_cbarg);
 191     }
 192
 193  end:
 194     BIO_free(in);
 195     OPENSSL_free(buf);
 196     ctx->desc->free_key(key);
 197
 198     return ok;
 199 }
 200
 201 static int
 202 msblob2key_export_object(void *vctx,
 203                          const void *reference, size_t reference_sz,
 204                          OSSL_CALLBACK *export_cb, void *export_cbarg)
 205 {
 206     struct msblob2key_ctx_st *ctx = vctx;
 207     OSSL_FUNC_keymgmt_export_fn *export =
 208         ossl_prov_get_keymgmt_export(ctx->desc->fns);
 209     void *keydata;
 210
 211     if (reference_sz == sizeof(keydata) && export != NULL) {
 212         /* The contents of the reference is the address to our object */
 213         keydata = *(void **)reference;
 214
 215         return export(keydata, ctx->selection, export_cb, export_cbarg);
 216     }
 217     return 0;
 218 }
 219
 220 /* ---------------------------------------------------------------------- */
 221
 222 #define dsa_decode_private_key  (b2i_of_void_fn *)ossl_b2i_DSA_after_header
 223 #define dsa_decode_public_key   (b2i_of_void_fn *)ossl_b2i_DSA_after_header
 224 #define dsa_adjust              NULL
 225 #define dsa_free                (void (*)(void *))DSA_free
 226
 227 /* ---------------------------------------------------------------------- */
 228
 229 #define rsa_decode_private_key  (b2i_of_void_fn *)ossl_b2i_RSA_after_header
 230 #define rsa_decode_public_key   (b2i_of_void_fn *)ossl_b2i_RSA_after_header
 231
 232 static void rsa_adjust(void *key, struct msblob2key_ctx_st *ctx)
 233 {
 234     ossl_rsa_set0_libctx(key, PROV_LIBCTX_OF(ctx->provctx));
 235 }
 236
 237 #define rsa_free                        (void (*)(void *))RSA_free
 238
 239 /* ---------------------------------------------------------------------- */
 240
 241 #define IMPLEMENT_MSBLOB(KEYTYPE, keytype)                              \
 242     static const struct keytype_desc_st mstype##2##keytype##_desc = {   \
 243         EVP_PKEY_##KEYTYPE, #KEYTYPE,                                   \
 244         ossl_##keytype##_keymgmt_functions,                             \
 245         keytype##_decode_private_key,                                   \
 246         keytype##_decode_public_key,                                    \
 247         keytype##_adjust,                                               \
 248         keytype##_free                                                  \
 249     };                                                                  \
 250     static OSSL_FUNC_decoder_newctx_fn msblob2##keytype##_newctx;       \
 251     static void *msblob2##keytype##_newctx(void *provctx)               \
 252     {                                                                   \
 253         return msblob2key_newctx(provctx, &mstype##2##keytype##_desc);  \
 254     }                                                                   \
 255     const OSSL_DISPATCH                                                 \
 256     ossl_msblob_to_##keytype##_decoder_functions[] = {                  \
 257         { OSSL_FUNC_DECODER_NEWCTX,                                     \
 258           (void (*)(void))msblob2##keytype##_newctx },                  \
 259         { OSSL_FUNC_DECODER_FREECTX,                                    \
 260           (void (*)(void))msblob2key_freectx },                         \
 261         { OSSL_FUNC_DECODER_DECODE,                                     \
 262           (void (*)(void))msblob2key_decode },                          \
 263         { OSSL_FUNC_DECODER_EXPORT_OBJECT,                              \
 264           (void (*)(void))msblob2key_export_object },                   \
 265         OSSL_DISPATCH_END                                               \
 266     }
 267
 268 #ifndef OPENSSL_NO_DSA
 269 IMPLEMENT_MSBLOB(DSA, dsa);
 270 #endif
 271 IMPLEMENT_MSBLOB(RSA, rsa);