apps/kdf.c

   1 /*
   2  * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (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 <string.h>
  11
  12 #include "apps.h"
  13 #include "progs.h"
  14 #include <openssl/bio.h>
  15 #include <openssl/err.h>
  16 #include <openssl/evp.h>
  17 #include <openssl/kdf.h>
  18 #include <openssl/params.h>
  19
  20 typedef enum OPTION_choice {
  21     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  22     OPT_KDFOPT, OPT_BIN, OPT_KEYLEN, OPT_OUT
  23 } OPTION_CHOICE;
  24
  25 const OPTIONS kdf_options[] = {
  26     {OPT_HELP_STR, 1, '-', "Usage: %s [options] kdf_name\n"},
  27     {OPT_HELP_STR, 1, '-', "kdf_name\t KDF algorithm.\n"},
  28
  29     OPT_SECTION("General"),
  30     {"help", OPT_HELP, '-', "Display this summary"},
  31     {"kdfopt", OPT_KDFOPT, 's', "KDF algorithm control parameters in n:v form."},
  32     {OPT_HELP_STR, 1, '-', "See 'Supported Controls' in the EVP_KDF_ docs"},
  33     {"keylen", OPT_KEYLEN, 's', "The size of the output derived key"},
  34
  35     OPT_SECTION("Output"),
  36     {"out", OPT_OUT, '>', "Output to filename rather than stdout"},
  37     {"binary", OPT_BIN, '-', "Output in binary format (Default is hexadecimal "
  38                              "output)"},
  39     {NULL}
  40 };
  41
  42 int kdf_main(int argc, char **argv)
  43 {
  44     int ret = 1, out_bin = 0;
  45     OPTION_CHOICE o;
  46     STACK_OF(OPENSSL_STRING) *opts = NULL;
  47     char *prog, *hexout = NULL;
  48     const char *outfile = NULL;
  49     unsigned char *dkm_bytes = NULL;
  50     size_t dkm_len = 0;
  51     BIO *out = NULL;
  52     EVP_KDF *kdf = NULL;
  53     EVP_KDF_CTX *ctx = NULL;
  54
  55     prog = opt_init(argc, argv, kdf_options);
  56     while ((o = opt_next()) != OPT_EOF) {
  57         switch (o) {
  58         default:
  59 opthelp:
  60             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  61             goto err;
  62         case OPT_HELP:
  63             opt_help(kdf_options);
  64             ret = 0;
  65             goto err;
  66         case OPT_BIN:
  67             out_bin = 1;
  68             break;
  69         case OPT_KEYLEN:
  70             dkm_len = (size_t)atoi(opt_arg());
  71             break;
  72         case OPT_OUT:
  73             outfile = opt_arg();
  74             break;
  75         case OPT_KDFOPT:
  76             if (opts == NULL)
  77                 opts = sk_OPENSSL_STRING_new_null();
  78             if (opts == NULL || !sk_OPENSSL_STRING_push(opts, opt_arg()))
  79                 goto opthelp;
  80             break;
  81         }
  82     }
  83     argc = opt_num_rest();
  84     argv = opt_rest();
  85
  86     if (argc != 1) {
  87         BIO_printf(bio_err, "Invalid number of extra arguments\n");
  88         goto opthelp;
  89     }
  90
  91     if ((kdf = EVP_KDF_fetch(NULL, argv[0], NULL)) == NULL) {
  92         BIO_printf(bio_err, "Invalid KDF name %s\n", argv[0]);
  93         goto opthelp;
  94     }
  95
  96     ctx = EVP_KDF_CTX_new(kdf);
  97     if (ctx == NULL)
  98         goto err;
  99
 100     if (opts != NULL) {
 101         int ok = 1;
 102         OSSL_PARAM *params =
 103             app_params_new_from_opts(opts, EVP_KDF_settable_ctx_params(kdf));
 104
 105         if (params == NULL)
 106             goto err;
 107
 108         if (!EVP_KDF_CTX_set_params(ctx, params)) {
 109             BIO_printf(bio_err, "KDF parameter error\n");
 110             ERR_print_errors(bio_err);
 111             ok = 0;
 112         }
 113         app_params_free(params);
 114         if (!ok)
 115             goto err;
 116     }
 117
 118     out = bio_open_default(outfile, 'w', out_bin ? FORMAT_BINARY : FORMAT_TEXT);
 119     if (out == NULL)
 120         goto err;
 121
 122     if (dkm_len <= 0) {
 123         BIO_printf(bio_err, "Invalid derived key length.\n");
 124         goto err;
 125     }
 126     dkm_bytes = app_malloc(dkm_len, "out buffer");
 127     if (dkm_bytes == NULL)
 128         goto err;
 129
 130     if (!EVP_KDF_derive(ctx, dkm_bytes, dkm_len)) {
 131         BIO_printf(bio_err, "EVP_KDF_derive failed\n");
 132         goto err;
 133     }
 134
 135     if (out_bin) {
 136         BIO_write(out, dkm_bytes, dkm_len);
 137     } else {
 138         hexout = OPENSSL_buf2hexstr(dkm_bytes, dkm_len);
 139         BIO_printf(out, "%s\n\n", hexout);
 140     }
 141
 142     ret = 0;
 143 err:
 144     if (ret != 0)
 145         ERR_print_errors(bio_err);
 146     OPENSSL_clear_free(dkm_bytes, dkm_len);
 147     sk_OPENSSL_STRING_free(opts);
 148     EVP_KDF_free(kdf);
 149     EVP_KDF_CTX_free(ctx);
 150     BIO_free(out);
 151     OPENSSL_free(hexout);
 152     return ret;
 153 }