1/*
2 * Copyright 2019-2021 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#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
20typedef enum OPTION_choice {
21    OPT_COMMON,
22    OPT_KDFOPT, OPT_BIN, OPT_KEYLEN, OPT_OUT,
23    OPT_CIPHER, OPT_DIGEST, OPT_MAC,
24    OPT_PROV_ENUM
25} OPTION_CHOICE;
26
27const OPTIONS kdf_options[] = {
28    {OPT_HELP_STR, 1, '-', "Usage: %s [options] kdf_name\n"},
29
30    OPT_SECTION("General"),
31    {"help", OPT_HELP, '-', "Display this summary"},
32    {"kdfopt", OPT_KDFOPT, 's', "KDF algorithm control parameters in n:v form"},
33    {"cipher", OPT_CIPHER, 's', "Cipher"},
34    {"digest", OPT_DIGEST, 's', "Digest"},
35    {"mac", OPT_MAC, 's', "MAC"},
36    {OPT_MORE_STR, 1, '-', "See 'Supported Controls' in the EVP_KDF_ docs\n"},
37    {"keylen", OPT_KEYLEN, 's', "The size of the output derived key"},
38
39    OPT_SECTION("Output"),
40    {"out", OPT_OUT, '>', "Output to filename rather than stdout"},
41    {"binary", OPT_BIN, '-',
42        "Output in binary format (default is hexadecimal)"},
43
44    OPT_PROV_OPTIONS,
45
46    OPT_PARAMETERS(),
47    {"kdf_name", 0, 0, "Name of the KDF algorithm"},
48    {NULL}
49};
50
51static char *alloc_kdf_algorithm_name(STACK_OF(OPENSSL_STRING) **optp,
52                                      const char *name, const char *arg)
53{
54    size_t len = strlen(name) + strlen(arg) + 2;
55    char *res;
56
57    if (*optp == NULL)
58        *optp = sk_OPENSSL_STRING_new_null();
59    if (*optp == NULL)
60        return NULL;
61
62    res = app_malloc(len, "algorithm name");
63    BIO_snprintf(res, len, "%s:%s", name, arg);
64    if (sk_OPENSSL_STRING_push(*optp, res))
65        return res;
66    OPENSSL_free(res);
67    return NULL;
68}
69
70int kdf_main(int argc, char **argv)
71{
72    int ret = 1, out_bin = 0;
73    OPTION_CHOICE o;
74    STACK_OF(OPENSSL_STRING) *opts = NULL;
75    char *prog, *hexout = NULL;
76    const char *outfile = NULL;
77    unsigned char *dkm_bytes = NULL;
78    size_t dkm_len = 0;
79    BIO *out = NULL;
80    EVP_KDF *kdf = NULL;
81    EVP_KDF_CTX *ctx = NULL;
82    char *digest = NULL, *cipher = NULL, *mac = NULL;
83
84    prog = opt_init(argc, argv, kdf_options);
85    while ((o = opt_next()) != OPT_EOF) {
86        switch (o) {
87        default:
88opthelp:
89            BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
90            goto err;
91        case OPT_HELP:
92            opt_help(kdf_options);
93            ret = 0;
94            goto err;
95        case OPT_BIN:
96            out_bin = 1;
97            break;
98        case OPT_KEYLEN:
99            dkm_len = (size_t)atoi(opt_arg());
100            break;
101        case OPT_OUT:
102            outfile = opt_arg();
103            break;
104        case OPT_KDFOPT:
105            if (opts == NULL)
106                opts = sk_OPENSSL_STRING_new_null();
107            if (opts == NULL || !sk_OPENSSL_STRING_push(opts, opt_arg()))
108                goto opthelp;
109            break;
110        case OPT_CIPHER:
111            OPENSSL_free(cipher);
112            cipher = alloc_kdf_algorithm_name(&opts, "cipher", opt_arg());
113            if (cipher == NULL)
114                goto opthelp;
115            break;
116        case OPT_DIGEST:
117            OPENSSL_free(digest);
118            digest = alloc_kdf_algorithm_name(&opts, "digest", opt_arg());
119            if (digest == NULL)
120                goto opthelp;
121            break;
122        case OPT_MAC:
123            OPENSSL_free(mac);
124            mac = alloc_kdf_algorithm_name(&opts, "mac", opt_arg());
125            if (mac == NULL)
126                goto opthelp;
127            break;
128        case OPT_PROV_CASES:
129            if (!opt_provider(o))
130                goto err;
131            break;
132        }
133    }
134
135    /* One argument, the KDF name. */
136    argc = opt_num_rest();
137    argv = opt_rest();
138    if (argc != 1)
139        goto opthelp;
140
141    if ((kdf = EVP_KDF_fetch(app_get0_libctx(), argv[0],
142                             app_get0_propq())) == NULL) {
143        BIO_printf(bio_err, "Invalid KDF name %s\n", argv[0]);
144        goto opthelp;
145    }
146
147    ctx = EVP_KDF_CTX_new(kdf);
148    if (ctx == NULL)
149        goto err;
150
151    if (opts != NULL) {
152        int ok = 1;
153        OSSL_PARAM *params =
154            app_params_new_from_opts(opts, EVP_KDF_settable_ctx_params(kdf));
155
156        if (params == NULL)
157            goto err;
158
159        if (!EVP_KDF_CTX_set_params(ctx, params)) {
160            BIO_printf(bio_err, "KDF parameter error\n");
161            ERR_print_errors(bio_err);
162            ok = 0;
163        }
164        app_params_free(params);
165        if (!ok)
166            goto err;
167    }
168
169    out = bio_open_default(outfile, 'w', out_bin ? FORMAT_BINARY : FORMAT_TEXT);
170    if (out == NULL)
171        goto err;
172
173    if (dkm_len <= 0) {
174        BIO_printf(bio_err, "Invalid derived key length.\n");
175        goto err;
176    }
177    dkm_bytes = app_malloc(dkm_len, "out buffer");
178    if (dkm_bytes == NULL)
179        goto err;
180
181    if (!EVP_KDF_derive(ctx, dkm_bytes, dkm_len, NULL)) {
182        BIO_printf(bio_err, "EVP_KDF_derive failed\n");
183        goto err;
184    }
185
186    if (out_bin) {
187        BIO_write(out, dkm_bytes, dkm_len);
188    } else {
189        hexout = OPENSSL_buf2hexstr(dkm_bytes, dkm_len);
190        if (hexout == NULL) {
191            BIO_printf(bio_err, "Memory allocation failure\n");
192            goto err;
193        }
194        BIO_printf(out, "%s\n\n", hexout);
195    }
196
197    ret = 0;
198err:
199    if (ret != 0)
200        ERR_print_errors(bio_err);
201    OPENSSL_clear_free(dkm_bytes, dkm_len);
202    sk_OPENSSL_STRING_free(opts);
203    EVP_KDF_free(kdf);
204    EVP_KDF_CTX_free(ctx);
205    BIO_free(out);
206    OPENSSL_free(hexout);
207    OPENSSL_free(cipher);
208    OPENSSL_free(digest);
209    OPENSSL_free(mac);
210    return ret;
211}
212