/src/openssl/providers/implementations/kdfs/sshkdf.c

Source (jump to first uncovered line)
/*
 * Copyright 2018-2024 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */


#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <openssl/evp.h>
#include <openssl/kdf.h>
#include <openssl/core_names.h>
#include <openssl/proverr.h>
#include "internal/cryptlib.h"
#include "internal/numbers.h"
#include "crypto/evp.h"
#include "prov/provider_ctx.h"
#include "prov/providercommon.h"
#include "prov/implementations.h"
#include "prov/provider_util.h"
#include "prov/securitycheck.h"

/* See RFC 4253, Section 7.2 */
static OSSL_FUNC_kdf_newctx_fn kdf_sshkdf_new;
static OSSL_FUNC_kdf_dupctx_fn kdf_sshkdf_dup;
static OSSL_FUNC_kdf_freectx_fn kdf_sshkdf_free;
static OSSL_FUNC_kdf_reset_fn kdf_sshkdf_reset;
static OSSL_FUNC_kdf_derive_fn kdf_sshkdf_derive;
static OSSL_FUNC_kdf_settable_ctx_params_fn kdf_sshkdf_settable_ctx_params;
static OSSL_FUNC_kdf_set_ctx_params_fn kdf_sshkdf_set_ctx_params;
static OSSL_FUNC_kdf_gettable_ctx_params_fn kdf_sshkdf_gettable_ctx_params;
static OSSL_FUNC_kdf_get_ctx_params_fn kdf_sshkdf_get_ctx_params;

static int SSHKDF(const EVP_MD *evp_md,
                  const unsigned char *key, size_t key_len,
                  const unsigned char *xcghash, size_t xcghash_len,
                  const unsigned char *session_id, size_t session_id_len,
                  char type, unsigned char *okey, size_t okey_len);

typedef struct {
    void *provctx;
    PROV_DIGEST digest;
    unsigned char *key; /* K */
    size_t key_len;
    unsigned char *xcghash; /* H */
    size_t xcghash_len;
    char type; /* X */
    unsigned char *session_id;
    size_t session_id_len;
    OSSL_FIPS_IND_DECLARE
} KDF_SSHKDF;

static void *kdf_sshkdf_new(void *provctx)
{
    KDF_SSHKDF *ctx;

    if (!ossl_prov_is_running())
        return NULL;

    if ((ctx = OPENSSL_zalloc(sizeof(*ctx))) != NULL) {
        ctx->provctx = provctx;
        OSSL_FIPS_IND_INIT(ctx)
    }
    return ctx;
}

static void kdf_sshkdf_free(void *vctx)
{
    KDF_SSHKDF *ctx = (KDF_SSHKDF *)vctx;

    if (ctx != NULL) {
        kdf_sshkdf_reset(ctx);
        OPENSSL_free(ctx);
    }
}

static void kdf_sshkdf_reset(void *vctx)
{
    KDF_SSHKDF *ctx = (KDF_SSHKDF *)vctx;
    void *provctx = ctx->provctx;

    ossl_prov_digest_reset(&ctx->digest);
    OPENSSL_clear_free(ctx->key, ctx->key_len);
    OPENSSL_clear_free(ctx->xcghash, ctx->xcghash_len);
    OPENSSL_clear_free(ctx->session_id, ctx->session_id_len);
    memset(ctx, 0, sizeof(*ctx));
    ctx->provctx = provctx;
}

static void *kdf_sshkdf_dup(void *vctx)
{
    const KDF_SSHKDF *src = (const KDF_SSHKDF *)vctx;
    KDF_SSHKDF *dest;

    dest = kdf_sshkdf_new(src->provctx);
    if (dest != NULL) {
        if (!ossl_prov_memdup(src->key, src->key_len,
                              &dest->key, &dest->key_len)
                || !ossl_prov_memdup(src->xcghash, src->xcghash_len,
                                     &dest->xcghash , &dest->xcghash_len)
                || !ossl_prov_memdup(src->session_id, src->session_id_len,
                                     &dest->session_id , &dest->session_id_len)
                || !ossl_prov_digest_copy(&dest->digest, &src->digest))
            goto err;
        dest->type = src->type;
        OSSL_FIPS_IND_COPY(dest, src)
    }
    return dest;

 err:
    kdf_sshkdf_free(dest);
    return NULL;
}

static int sshkdf_set_membuf(unsigned char **dst, size_t *dst_len,
                             const OSSL_PARAM *p)
{
    OPENSSL_clear_free(*dst, *dst_len);
    *dst = NULL;
    *dst_len = 0;
    return OSSL_PARAM_get_octet_string(p, (void **)dst, 0, dst_len);
}

#ifdef FIPS_MODULE
static int fips_digest_check_passed(KDF_SSHKDF *ctx, const EVP_MD *md)
{
    OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
    /*
     * Perform digest check
     *
     * According to NIST SP 800-135r1 section 5.2, the valid hash functions are
     * specified in FIPS 180-3. ACVP also only lists the same set of hash
     * functions.
     */
    int digest_unapproved = !EVP_MD_is_a(md, SN_sha1)
        && !EVP_MD_is_a(md, SN_sha224)
        && !EVP_MD_is_a(md, SN_sha256)
        && !EVP_MD_is_a(md, SN_sha384)
        && !EVP_MD_is_a(md, SN_sha512);

    if (digest_unapproved) {
        if (!OSSL_FIPS_IND_ON_UNAPPROVED(ctx, OSSL_FIPS_IND_SETTABLE0,
                                         libctx, "SSHKDF", "Digest",
                                         ossl_fips_config_sshkdf_digest_check)) {
            ERR_raise(ERR_LIB_PROV, PROV_R_DIGEST_NOT_ALLOWED);
            return 0;
        }
    }
    return 1;
}

static int fips_key_check_passed(KDF_SSHKDF *ctx)
{
    OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
    int key_approved = ossl_kdf_check_key_size(ctx->key_len);

    if (!key_approved) {
        if (!OSSL_FIPS_IND_ON_UNAPPROVED(ctx, OSSL_FIPS_IND_SETTABLE1,
                                         libctx, "SSHKDF", "Key size",
                                         ossl_fips_config_sshkdf_key_check)) {
            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
            return 0;
        }
    }
    return 1;
}
#endif

static int kdf_sshkdf_derive(void *vctx, unsigned char *key, size_t keylen,
                             const OSSL_PARAM params[])
{
    KDF_SSHKDF *ctx = (KDF_SSHKDF *)vctx;
    const EVP_MD *md;

    if (!ossl_prov_is_running() || !kdf_sshkdf_set_ctx_params(ctx, params))
        return 0;

    md = ossl_prov_digest_md(&ctx->digest);
    if (md == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_MESSAGE_DIGEST);
        return 0;
    }
    if (ctx->key == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_KEY);
        return 0;
    }
    if (ctx->xcghash == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_XCGHASH);
        return 0;
    }
    if (ctx->session_id == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SESSION_ID);
        return 0;
    }
    if (ctx->type == 0) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_TYPE);
        return 0;
    }

    return SSHKDF(md, ctx->key, ctx->key_len,
                  ctx->xcghash, ctx->xcghash_len,
                  ctx->session_id, ctx->session_id_len,
                  ctx->type, key, keylen);
}

/* Machine generated by util/perl/OpenSSL/paramnames.pm */
#ifndef sshkdf_set_ctx_params_list
static const OSSL_PARAM sshkdf_set_ctx_params_list[] = {
    OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
    OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0),
    OSSL_PARAM_octet_string(OSSL_KDF_PARAM_KEY, NULL, 0),
    OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SSHKDF_XCGHASH, NULL, 0),
    OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SSHKDF_SESSION_ID, NULL, 0),
    OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_SSHKDF_TYPE, NULL, 0),
# if defined(FIPS_MODULE)
    OSSL_PARAM_int(OSSL_KDF_PARAM_FIPS_DIGEST_CHECK, NULL),
# endif
# if defined(FIPS_MODULE)
    OSSL_PARAM_int(OSSL_KDF_PARAM_FIPS_KEY_CHECK, NULL),
# endif
    OSSL_PARAM_END
};
#endif

#ifndef sshkdf_set_ctx_params_st
struct sshkdf_set_ctx_params_st {
    OSSL_PARAM *digest;
    OSSL_PARAM *engine;
# if defined(FIPS_MODULE)
    OSSL_PARAM *ind_d;
# endif
# if defined(FIPS_MODULE)
    OSSL_PARAM *ind_k;
# endif
    OSSL_PARAM *key;
    OSSL_PARAM *propq;
    OSSL_PARAM *sid;
    OSSL_PARAM *type;
    OSSL_PARAM *xcg;
};
#endif

#ifndef sshkdf_set_ctx_params_decoder
static int sshkdf_set_ctx_params_decoder
    (const OSSL_PARAM *p, struct sshkdf_set_ctx_params_st *r)
{
    const char *s;

    memset(r, 0, sizeof(*r));
    if (p != NULL)
        for (; (s = p->key) != NULL; p++)
            switch(s[0]) {
            default:
                break;
            case 'd':
                switch(s[1]) {
                default:
                    break;
                case 'i':
                    switch(s[2]) {
                    default:
                        break;
                    case 'g':
                        switch(s[3]) {
                        default:
                            break;
                        case 'e':
                            switch(s[4]) {
                            default:
                                break;
                            case 's':
                                switch(s[5]) {
                                default:
                                    break;
                                case 't':
                                    switch(s[6]) {
                                    default:
                                        break;
                                    case '-':
# if defined(FIPS_MODULE)
                                        if (ossl_likely(strcmp("check", s + 7) == 0)) {
                                            /* KDF_PARAM_FIPS_DIGEST_CHECK */
                                            if (ossl_unlikely(r->ind_d != NULL)) {
                                                ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                                               "param %s is repeated", s);
                                                return 0;
                                            }
                                            r->ind_d = (OSSL_PARAM *)p;
                                        }
# endif
                                        break;
                                    case '\0':
                                        if (ossl_unlikely(r->digest != NULL)) {
                                            ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                                           "param %s is repeated", s);
                                            return 0;
                                        }
                                        r->digest = (OSSL_PARAM *)p;
                                    }
                                }
                            }
                        }
                    }
                }
                break;
            case 'e':
                if (ossl_likely(strcmp("ngine", s + 1) == 0)) {
                    /* ALG_PARAM_ENGINE */
                    if (ossl_unlikely(r->engine != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->engine = (OSSL_PARAM *)p;
                }
                break;
            case 'k':
                switch(s[1]) {
                default:
                    break;
                case 'e':
                    switch(s[2]) {
                    default:
                        break;
                    case 'y':
                        switch(s[3]) {
                        default:
                            break;
                        case '-':
# if defined(FIPS_MODULE)
                            if (ossl_likely(strcmp("check", s + 4) == 0)) {
                                /* KDF_PARAM_FIPS_KEY_CHECK */
                                if (ossl_unlikely(r->ind_k != NULL)) {
                                    ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                                   "param %s is repeated", s);
                                    return 0;
                                }
                                r->ind_k = (OSSL_PARAM *)p;
                            }
# endif
                            break;
                        case '\0':
                            if (ossl_unlikely(r->key != NULL)) {
                                ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                               "param %s is repeated", s);
                                return 0;
                            }
                            r->key = (OSSL_PARAM *)p;
                        }
                    }
                }
                break;
            case 'p':
                if (ossl_likely(strcmp("roperties", s + 1) == 0)) {
                    /* KDF_PARAM_PROPERTIES */
                    if (ossl_unlikely(r->propq != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->propq = (OSSL_PARAM *)p;
                }
                break;
            case 's':
                if (ossl_likely(strcmp("ession_id", s + 1) == 0)) {
                    /* KDF_PARAM_SSHKDF_SESSION_ID */
                    if (ossl_unlikely(r->sid != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->sid = (OSSL_PARAM *)p;
                }
                break;
            case 't':
                if (ossl_likely(strcmp("ype", s + 1) == 0)) {
                    /* KDF_PARAM_SSHKDF_TYPE */
                    if (ossl_unlikely(r->type != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->type = (OSSL_PARAM *)p;
                }
                break;
            case 'x':
                if (ossl_likely(strcmp("cghash", s + 1) == 0)) {
                    /* KDF_PARAM_SSHKDF_XCGHASH */
                    if (ossl_unlikely(r->xcg != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->xcg = (OSSL_PARAM *)p;
                }
            }
    return 1;
}
#endif
/* End of machine generated */

static int kdf_sshkdf_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
    struct sshkdf_set_ctx_params_st p;
    KDF_SSHKDF *ctx = vctx;
    OSSL_LIB_CTX *provctx;

    if (ctx == NULL || !sshkdf_set_ctx_params_decoder(params, &p))
        return 0;

    provctx = PROV_LIBCTX_OF(ctx->provctx);

    if (!OSSL_FIPS_IND_SET_CTX_FROM_PARAM(ctx, OSSL_FIPS_IND_SETTABLE0, p.ind_d))
        return 0;
    if (!OSSL_FIPS_IND_SET_CTX_FROM_PARAM(ctx, OSSL_FIPS_IND_SETTABLE1, p.ind_k))
        return 0;

    if (p.digest != NULL) {
        const EVP_MD *md = NULL;

        if (!ossl_prov_digest_load(&ctx->digest, p.digest,
                                   p.propq, p.engine, provctx))
            return 0;

        md = ossl_prov_digest_md(&ctx->digest);
        if (EVP_MD_xof(md)) {
            ERR_raise(ERR_LIB_PROV, PROV_R_XOF_DIGESTS_NOT_ALLOWED);
            return 0;
        }

#ifdef FIPS_MODULE
        if (!fips_digest_check_passed(ctx, md))
            return 0;
#endif
    }

    if (p.key != NULL) {
        if (!sshkdf_set_membuf(&ctx->key, &ctx->key_len, p.key))
            return 0;

#ifdef FIPS_MODULE
        if (!fips_key_check_passed(ctx))
            return 0;
#endif
    }

    if (p.xcg != NULL
            && !sshkdf_set_membuf(&ctx->xcghash, &ctx->xcghash_len, p.xcg))
        return 0;

    if (p.sid != NULL
            && !sshkdf_set_membuf(&ctx->session_id, &ctx->session_id_len, p.sid))
        return 0;

    if (p.type != NULL) {
        const char *kdftype;

        if (!OSSL_PARAM_get_utf8_string_ptr(p.type, &kdftype))
            return 0;
        /* Expect one character (byte in this case) */
        if (kdftype == NULL || p.type->data_size != 1)
            return 0;
        if (kdftype[0] < 65 || kdftype[0] > 70) {
            ERR_raise(ERR_LIB_PROV, PROV_R_VALUE_ERROR);
            return 0;
        }
        ctx->type = kdftype[0];
    }
    return 1;
}

static const OSSL_PARAM *kdf_sshkdf_settable_ctx_params(ossl_unused void *ctx,
                                                        ossl_unused void *p_ctx)
{
    return sshkdf_set_ctx_params_list;
}

/* Machine generated by util/perl/OpenSSL/paramnames.pm */
#ifndef sshkdf_get_ctx_params_list
static const OSSL_PARAM sshkdf_get_ctx_params_list[] = {
    OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
# if defined(FIPS_MODULE)
    OSSL_PARAM_int(OSSL_KDF_PARAM_FIPS_APPROVED_INDICATOR, NULL),
# endif
    OSSL_PARAM_END
};
#endif

#ifndef sshkdf_get_ctx_params_st
struct sshkdf_get_ctx_params_st {
# if defined(FIPS_MODULE)
    OSSL_PARAM *ind;
# endif
    OSSL_PARAM *size;
};
#endif

#ifndef sshkdf_get_ctx_params_decoder
static int sshkdf_get_ctx_params_decoder
    (const OSSL_PARAM *p, struct sshkdf_get_ctx_params_st *r)
{
    const char *s;

    memset(r, 0, sizeof(*r));
    if (p != NULL)
        for (; (s = p->key) != NULL; p++)
            switch(s[0]) {
            default:
                break;
            case 'f':
# if defined(FIPS_MODULE)
                if (ossl_likely(strcmp("ips-indicator", s + 1) == 0)) {
                    /* KDF_PARAM_FIPS_APPROVED_INDICATOR */
                    if (ossl_unlikely(r->ind != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->ind = (OSSL_PARAM *)p;
                }
# endif
                break;
            case 's':
                if (ossl_likely(strcmp("ize", s + 1) == 0)) {
                    /* KDF_PARAM_SIZE */
                    if (ossl_unlikely(r->size != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->size = (OSSL_PARAM *)p;
                }
            }
    return 1;
}
#endif
/* End of machine generated */

static int kdf_sshkdf_get_ctx_params(void *vctx, OSSL_PARAM params[])
{
    KDF_SSHKDF *ctx = (KDF_SSHKDF *)vctx;
    struct sshkdf_get_ctx_params_st p;

    if (ctx == NULL || !sshkdf_get_ctx_params_decoder(params, &p))
        return 0;

    if (p.size != NULL && !OSSL_PARAM_set_size_t(p.size, SIZE_MAX))
        return 0;

    if (!OSSL_FIPS_IND_GET_CTX_FROM_PARAM(ctx, p.ind))
        return 0;
    return 1;
}

static const OSSL_PARAM *kdf_sshkdf_gettable_ctx_params(ossl_unused void *ctx,
                                                        ossl_unused void *p_ctx)
{
    return sshkdf_get_ctx_params_list;
}

const OSSL_DISPATCH ossl_kdf_sshkdf_functions[] = {
    { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_sshkdf_new },
    { OSSL_FUNC_KDF_DUPCTX, (void(*)(void))kdf_sshkdf_dup },
    { OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_sshkdf_free },
    { OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_sshkdf_reset },
    { OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_sshkdf_derive },
    { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
      (void(*)(void))kdf_sshkdf_settable_ctx_params },
    { OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_sshkdf_set_ctx_params },
    { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
      (void(*)(void))kdf_sshkdf_gettable_ctx_params },
    { OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_sshkdf_get_ctx_params },
    OSSL_DISPATCH_END
};

static int SSHKDF(const EVP_MD *evp_md,
                  const unsigned char *key, size_t key_len,
                  const unsigned char *xcghash, size_t xcghash_len,
                  const unsigned char *session_id, size_t session_id_len,
                  char type, unsigned char *okey, size_t okey_len)
{
    EVP_MD_CTX *md = NULL;
    unsigned char digest[EVP_MAX_MD_SIZE];
    unsigned int dsize = 0;
    size_t cursize = 0;
    int ret = 0;

    md = EVP_MD_CTX_new();
    if (md == NULL)
        return 0;

    if (!EVP_DigestInit_ex(md, evp_md, NULL))
        goto out;

    if (!EVP_DigestUpdate(md, key, key_len))
        goto out;

    if (!EVP_DigestUpdate(md, xcghash, xcghash_len))
        goto out;

    if (!EVP_DigestUpdate(md, &type, 1))
        goto out;

    if (!EVP_DigestUpdate(md, session_id, session_id_len))
        goto out;

    if (!EVP_DigestFinal_ex(md, digest, &dsize))
        goto out;

    if (okey_len < dsize) {
        memcpy(okey, digest, okey_len);
        ret = 1;
        goto out;
    }

    memcpy(okey, digest, dsize);

    for (cursize = dsize; cursize < okey_len; cursize += dsize) {

        if (!EVP_DigestInit_ex(md, evp_md, NULL))
            goto out;

        if (!EVP_DigestUpdate(md, key, key_len))
            goto out;

        if (!EVP_DigestUpdate(md, xcghash, xcghash_len))
            goto out;

        if (!EVP_DigestUpdate(md, okey, cursize))
            goto out;

        if (!EVP_DigestFinal_ex(md, digest, &dsize))
            goto out;

        if (okey_len < cursize + dsize) {
            memcpy(okey + cursize, digest, okey_len - cursize);
            ret = 1;
            goto out;
        }

        memcpy(okey + cursize, digest, dsize);
    }

    ret = 1;

out:
    EVP_MD_CTX_free(md);
    OPENSSL_cleanse(digest, EVP_MAX_MD_SIZE);
    return ret;
}

Coverage Report

Created: 2025-08-25 06:30

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 2018-2024 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		#include <stdlib.h>
12		#include <stdarg.h>
13		#include <string.h>
14		#include <openssl/evp.h>
15		#include <openssl/kdf.h>
16		#include <openssl/core_names.h>
17		#include <openssl/proverr.h>
18		#include "internal/cryptlib.h"
19		#include "internal/numbers.h"
20		#include "crypto/evp.h"
21		#include "prov/provider_ctx.h"
22		#include "prov/providercommon.h"
23		#include "prov/implementations.h"
24		#include "prov/provider_util.h"
25		#include "prov/securitycheck.h"
26
27		/* See RFC 4253, Section 7.2 */
28		static OSSL_FUNC_kdf_newctx_fn kdf_sshkdf_new;
29		static OSSL_FUNC_kdf_dupctx_fn kdf_sshkdf_dup;
30		static OSSL_FUNC_kdf_freectx_fn kdf_sshkdf_free;
31		static OSSL_FUNC_kdf_reset_fn kdf_sshkdf_reset;
32		static OSSL_FUNC_kdf_derive_fn kdf_sshkdf_derive;
33		static OSSL_FUNC_kdf_settable_ctx_params_fn kdf_sshkdf_settable_ctx_params;
34		static OSSL_FUNC_kdf_set_ctx_params_fn kdf_sshkdf_set_ctx_params;
35		static OSSL_FUNC_kdf_gettable_ctx_params_fn kdf_sshkdf_gettable_ctx_params;
36		static OSSL_FUNC_kdf_get_ctx_params_fn kdf_sshkdf_get_ctx_params;
37
38		static int SSHKDF(const EVP_MD *evp_md,
39		const unsigned char *key, size_t key_len,
40		const unsigned char *xcghash, size_t xcghash_len,
41		const unsigned char *session_id, size_t session_id_len,
42		char type, unsigned char *okey, size_t okey_len);
43
44		typedef struct {
45		void *provctx;
46		PROV_DIGEST digest;
47		unsigned char key; / K */
48		size_t key_len;
49		unsigned char xcghash; / H */
50		size_t xcghash_len;
51		char type; /* X */
52		unsigned char *session_id;
53		size_t session_id_len;
54		OSSL_FIPS_IND_DECLARE
55		} KDF_SSHKDF;
56
57		static void kdf_sshkdf_new(void provctx)
58	0	{
59	0	KDF_SSHKDF *ctx;
60
61	0	if (!ossl_prov_is_running())
62	0	return NULL;
63
64	0	if ((ctx = OPENSSL_zalloc(sizeof(*ctx))) != NULL) {
65	0	ctx->provctx = provctx;
66	0	OSSL_FIPS_IND_INIT(ctx)
67	0	}
68	0	return ctx;
69	0	}
70
71		static void kdf_sshkdf_free(void *vctx)
72	0	{
73	0	KDF_SSHKDF ctx = (KDF_SSHKDF )vctx;
74
75	0	if (ctx != NULL) {
76	0	kdf_sshkdf_reset(ctx);
77	0	OPENSSL_free(ctx);
78	0	}
79	0	}
80
81		static void kdf_sshkdf_reset(void *vctx)
82	0	{
83	0	KDF_SSHKDF ctx = (KDF_SSHKDF )vctx;
84	0	void *provctx = ctx->provctx;
85
86	0	ossl_prov_digest_reset(&ctx->digest);
87	0	OPENSSL_clear_free(ctx->key, ctx->key_len);
88	0	OPENSSL_clear_free(ctx->xcghash, ctx->xcghash_len);
89	0	OPENSSL_clear_free(ctx->session_id, ctx->session_id_len);
90	0	memset(ctx, 0, sizeof(*ctx));
91	0	ctx->provctx = provctx;
92	0	}
93
94		static void kdf_sshkdf_dup(void vctx)
95	0	{
96	0	const KDF_SSHKDF src = (const KDF_SSHKDF )vctx;
97	0	KDF_SSHKDF *dest;
98
99	0	dest = kdf_sshkdf_new(src->provctx);
100	0	if (dest != NULL) {
101	0	if (!ossl_prov_memdup(src->key, src->key_len,
102	0	&dest->key, &dest->key_len)
103	0	\|\| !ossl_prov_memdup(src->xcghash, src->xcghash_len,
104	0	&dest->xcghash , &dest->xcghash_len)
105	0	\|\| !ossl_prov_memdup(src->session_id, src->session_id_len,
106	0	&dest->session_id , &dest->session_id_len)
107	0	\|\| !ossl_prov_digest_copy(&dest->digest, &src->digest))
108	0	goto err;
109	0	dest->type = src->type;
110	0	OSSL_FIPS_IND_COPY(dest, src)
111	0	}
112	0	return dest;
113
114	0	err:
115	0	kdf_sshkdf_free(dest);
116	0	return NULL;
117	0	}
118
119		static int sshkdf_set_membuf(unsigned char *dst, size_t dst_len,
120		const OSSL_PARAM *p)
121	0	{
122	0	OPENSSL_clear_free(dst, dst_len);
123	0	*dst = NULL;
124	0	*dst_len = 0;
125	0	return OSSL_PARAM_get_octet_string(p, (void **)dst, 0, dst_len);
126	0	}
127
128		#ifdef FIPS_MODULE
129		static int fips_digest_check_passed(KDF_SSHKDF ctx, const EVP_MD md)
130		{
131		OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
132		/*
133		* Perform digest check
134		*
135		* According to NIST SP 800-135r1 section 5.2, the valid hash functions are
136		* specified in FIPS 180-3. ACVP also only lists the same set of hash
137		* functions.
138		*/
139		int digest_unapproved = !EVP_MD_is_a(md, SN_sha1)
140		&& !EVP_MD_is_a(md, SN_sha224)
141		&& !EVP_MD_is_a(md, SN_sha256)
142		&& !EVP_MD_is_a(md, SN_sha384)
143		&& !EVP_MD_is_a(md, SN_sha512);
144
145		if (digest_unapproved) {
146		if (!OSSL_FIPS_IND_ON_UNAPPROVED(ctx, OSSL_FIPS_IND_SETTABLE0,
147		libctx, "SSHKDF", "Digest",
148		ossl_fips_config_sshkdf_digest_check)) {
149		ERR_raise(ERR_LIB_PROV, PROV_R_DIGEST_NOT_ALLOWED);
150		return 0;
151		}
152		}
153		return 1;
154		}
155
156		static int fips_key_check_passed(KDF_SSHKDF *ctx)
157		{
158		OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
159		int key_approved = ossl_kdf_check_key_size(ctx->key_len);
160
161		if (!key_approved) {
162		if (!OSSL_FIPS_IND_ON_UNAPPROVED(ctx, OSSL_FIPS_IND_SETTABLE1,
163		libctx, "SSHKDF", "Key size",
164		ossl_fips_config_sshkdf_key_check)) {
165		ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
166		return 0;
167		}
168		}
169		return 1;
170		}
171		#endif
172
173		static int kdf_sshkdf_derive(void vctx, unsigned char key, size_t keylen,
174		const OSSL_PARAM params[])
175	0	{
176	0	KDF_SSHKDF ctx = (KDF_SSHKDF )vctx;
177	0	const EVP_MD *md;
178
179	0	if (!ossl_prov_is_running() \|\| !kdf_sshkdf_set_ctx_params(ctx, params))
180	0	return 0;
181
182	0	md = ossl_prov_digest_md(&ctx->digest);
183	0	if (md == NULL) {
184	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_MESSAGE_DIGEST);
185	0	return 0;
186	0	}
187	0	if (ctx->key == NULL) {
188	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_KEY);
189	0	return 0;
190	0	}
191	0	if (ctx->xcghash == NULL) {
192	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_XCGHASH);
193	0	return 0;
194	0	}
195	0	if (ctx->session_id == NULL) {
196	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SESSION_ID);
197	0	return 0;
198	0	}
199	0	if (ctx->type == 0) {
200	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_TYPE);
201	0	return 0;
202	0	}
203
204	0	return SSHKDF(md, ctx->key, ctx->key_len,
205	0	ctx->xcghash, ctx->xcghash_len,
206	0	ctx->session_id, ctx->session_id_len,
207	0	ctx->type, key, keylen);
208	0	}
209
210		/* Machine generated by util/perl/OpenSSL/paramnames.pm */
211		#ifndef sshkdf_set_ctx_params_list
212		static const OSSL_PARAM sshkdf_set_ctx_params_list[] = {
213		OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
214		OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0),
215		OSSL_PARAM_octet_string(OSSL_KDF_PARAM_KEY, NULL, 0),
216		OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SSHKDF_XCGHASH, NULL, 0),
217		OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SSHKDF_SESSION_ID, NULL, 0),
218		OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_SSHKDF_TYPE, NULL, 0),
219		# if defined(FIPS_MODULE)
220		OSSL_PARAM_int(OSSL_KDF_PARAM_FIPS_DIGEST_CHECK, NULL),
221		# endif
222		# if defined(FIPS_MODULE)
223		OSSL_PARAM_int(OSSL_KDF_PARAM_FIPS_KEY_CHECK, NULL),
224		# endif
225		OSSL_PARAM_END
226		};
227		#endif
228
229		#ifndef sshkdf_set_ctx_params_st
230		struct sshkdf_set_ctx_params_st {
231		OSSL_PARAM *digest;
232		OSSL_PARAM *engine;
233		# if defined(FIPS_MODULE)
234		OSSL_PARAM *ind_d;
235		# endif
236		# if defined(FIPS_MODULE)
237		OSSL_PARAM *ind_k;
238		# endif
239		OSSL_PARAM *key;
240		OSSL_PARAM *propq;
241		OSSL_PARAM *sid;
242		OSSL_PARAM *type;
243		OSSL_PARAM *xcg;
244		};
245		#endif
246
247		#ifndef sshkdf_set_ctx_params_decoder
248		static int sshkdf_set_ctx_params_decoder
249		(const OSSL_PARAM p, struct sshkdf_set_ctx_params_st r)
250	0	{
251	0	const char *s;
252
253	0	memset(r, 0, sizeof(*r));
254	0	if (p != NULL)
255	0	for (; (s = p->key) != NULL; p++)
256	0	switch(s[0]) {
257	0	default:
258	0	break;
259	0	case 'd':
260	0	switch(s[1]) {
261	0	default:
262	0	break;
263	0	case 'i':
264	0	switch(s[2]) {
265	0	default:
266	0	break;
267	0	case 'g':
268	0	switch(s[3]) {
269	0	default:
270	0	break;
271	0	case 'e':
272	0	switch(s[4]) {
273	0	default:
274	0	break;
275	0	case 's':
276	0	switch(s[5]) {
277	0	default:
278	0	break;
279	0	case 't':
280	0	switch(s[6]) {
281	0	default:
282	0	break;
283	0	case '-':
284		# if defined(FIPS_MODULE)
285		if (ossl_likely(strcmp("check", s + 7) == 0)) {
286		/* KDF_PARAM_FIPS_DIGEST_CHECK */
287		if (ossl_unlikely(r->ind_d != NULL)) {
288		ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
289		"param %s is repeated", s);
290		return 0;
291		}
292		r->ind_d = (OSSL_PARAM *)p;
293		}
294		# endif
295	0	break;
296	0	case '\0':
297	0	if (ossl_unlikely(r->digest != NULL)) {
298	0	ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
299	0	"param %s is repeated", s);
300	0	return 0;
301	0	}
302	0	r->digest = (OSSL_PARAM *)p;
303	0	}
304	0	}
305	0	}
306	0	}
307	0	}
308	0	}
309	0	break;
310	0	case 'e':
311	0	if (ossl_likely(strcmp("ngine", s + 1) == 0)) {
312		/* ALG_PARAM_ENGINE */
313	0	if (ossl_unlikely(r->engine != NULL)) {
314	0	ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
315	0	"param %s is repeated", s);
316	0	return 0;
317	0	}
318	0	r->engine = (OSSL_PARAM *)p;
319	0	}
320	0	break;
321	0	case 'k':
322	0	switch(s[1]) {
323	0	default:
324	0	break;
325	0	case 'e':
326	0	switch(s[2]) {
327	0	default:
328	0	break;
329	0	case 'y':
330	0	switch(s[3]) {
331	0	default:
332	0	break;
333	0	case '-':
334		# if defined(FIPS_MODULE)
335		if (ossl_likely(strcmp("check", s + 4) == 0)) {
336		/* KDF_PARAM_FIPS_KEY_CHECK */
337		if (ossl_unlikely(r->ind_k != NULL)) {
338		ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
339		"param %s is repeated", s);
340		return 0;
341		}
342		r->ind_k = (OSSL_PARAM *)p;
343		}
344		# endif
345	0	break;
346	0	case '\0':
347	0	if (ossl_unlikely(r->key != NULL)) {
348	0	ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
349	0	"param %s is repeated", s);
350	0	return 0;
351	0	}
352	0	r->key = (OSSL_PARAM *)p;
353	0	}
354	0	}
355	0	}
356	0	break;
357	0	case 'p':
358	0	if (ossl_likely(strcmp("roperties", s + 1) == 0)) {
359		/* KDF_PARAM_PROPERTIES */
360	0	if (ossl_unlikely(r->propq != NULL)) {
361	0	ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
362	0	"param %s is repeated", s);
363	0	return 0;
364	0	}
365	0	r->propq = (OSSL_PARAM *)p;
366	0	}
367	0	break;
368	0	case 's':
369	0	if (ossl_likely(strcmp("ession_id", s + 1) == 0)) {
370		/* KDF_PARAM_SSHKDF_SESSION_ID */
371	0	if (ossl_unlikely(r->sid != NULL)) {
372	0	ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
373	0	"param %s is repeated", s);
374	0	return 0;
375	0	}
376	0	r->sid = (OSSL_PARAM *)p;
377	0	}
378	0	break;
379	0	case 't':
380	0	if (ossl_likely(strcmp("ype", s + 1) == 0)) {
381		/* KDF_PARAM_SSHKDF_TYPE */
382	0	if (ossl_unlikely(r->type != NULL)) {
383	0	ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
384	0	"param %s is repeated", s);
385	0	return 0;
386	0	}
387	0	r->type = (OSSL_PARAM *)p;
388	0	}
389	0	break;
390	0	case 'x':
391	0	if (ossl_likely(strcmp("cghash", s + 1) == 0)) {
392		/* KDF_PARAM_SSHKDF_XCGHASH */
393	0	if (ossl_unlikely(r->xcg != NULL)) {
394	0	ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
395	0	"param %s is repeated", s);
396	0	return 0;
397	0	}
398	0	r->xcg = (OSSL_PARAM *)p;
399	0	}
400	0	}
401	0	return 1;
402	0	}
403		#endif
404		/* End of machine generated */
405
406		static int kdf_sshkdf_set_ctx_params(void *vctx, const OSSL_PARAM params[])
407	0	{
408	0	struct sshkdf_set_ctx_params_st p;
409	0	KDF_SSHKDF *ctx = vctx;
410	0	OSSL_LIB_CTX *provctx;
411
412	0	if (ctx == NULL \|\| !sshkdf_set_ctx_params_decoder(params, &p))
413	0	return 0;
414
415	0	provctx = PROV_LIBCTX_OF(ctx->provctx);
416
417	0	if (!OSSL_FIPS_IND_SET_CTX_FROM_PARAM(ctx, OSSL_FIPS_IND_SETTABLE0, p.ind_d))
418	0	return 0;
419	0	if (!OSSL_FIPS_IND_SET_CTX_FROM_PARAM(ctx, OSSL_FIPS_IND_SETTABLE1, p.ind_k))
420	0	return 0;
421
422	0	if (p.digest != NULL) {
423	0	const EVP_MD *md = NULL;
424
425	0	if (!ossl_prov_digest_load(&ctx->digest, p.digest,
426	0	p.propq, p.engine, provctx))
427	0	return 0;
428
429	0	md = ossl_prov_digest_md(&ctx->digest);
430	0	if (EVP_MD_xof(md)) {
431	0	ERR_raise(ERR_LIB_PROV, PROV_R_XOF_DIGESTS_NOT_ALLOWED);
432	0	return 0;
433	0	}
434
435		#ifdef FIPS_MODULE
436		if (!fips_digest_check_passed(ctx, md))
437		return 0;
438		#endif
439	0	}
440
441	0	if (p.key != NULL) {
442	0	if (!sshkdf_set_membuf(&ctx->key, &ctx->key_len, p.key))
443	0	return 0;
444
445		#ifdef FIPS_MODULE
446		if (!fips_key_check_passed(ctx))
447		return 0;
448		#endif
449	0	}
450
451	0	if (p.xcg != NULL
452	0	&& !sshkdf_set_membuf(&ctx->xcghash, &ctx->xcghash_len, p.xcg))
453	0	return 0;
454
455	0	if (p.sid != NULL
456	0	&& !sshkdf_set_membuf(&ctx->session_id, &ctx->session_id_len, p.sid))
457	0	return 0;
458
459	0	if (p.type != NULL) {
460	0	const char *kdftype;
461
462	0	if (!OSSL_PARAM_get_utf8_string_ptr(p.type, &kdftype))
463	0	return 0;
464		/* Expect one character (byte in this case) */
465	0	if (kdftype == NULL \|\| p.type->data_size != 1)
466	0	return 0;
467	0	if (kdftype[0] < 65 \|\| kdftype[0] > 70) {
468	0	ERR_raise(ERR_LIB_PROV, PROV_R_VALUE_ERROR);
469	0	return 0;
470	0	}
471	0	ctx->type = kdftype[0];
472	0	}
473	0	return 1;
474	0	}
475
476		static const OSSL_PARAM kdf_sshkdf_settable_ctx_params(ossl_unused void ctx,
477		ossl_unused void *p_ctx)
478	0	{
479	0	return sshkdf_set_ctx_params_list;
480	0	}
481
482		/* Machine generated by util/perl/OpenSSL/paramnames.pm */
483		#ifndef sshkdf_get_ctx_params_list
484		static const OSSL_PARAM sshkdf_get_ctx_params_list[] = {
485		OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
486		# if defined(FIPS_MODULE)
487		OSSL_PARAM_int(OSSL_KDF_PARAM_FIPS_APPROVED_INDICATOR, NULL),
488		# endif
489		OSSL_PARAM_END
490		};
491		#endif
492
493		#ifndef sshkdf_get_ctx_params_st
494		struct sshkdf_get_ctx_params_st {
495		# if defined(FIPS_MODULE)
496		OSSL_PARAM *ind;
497		# endif
498		OSSL_PARAM *size;
499		};
500		#endif
501
502		#ifndef sshkdf_get_ctx_params_decoder
503		static int sshkdf_get_ctx_params_decoder
504		(const OSSL_PARAM p, struct sshkdf_get_ctx_params_st r)
505	0	{
506	0	const char *s;
507
508	0	memset(r, 0, sizeof(*r));
509	0	if (p != NULL)
510	0	for (; (s = p->key) != NULL; p++)
511	0	switch(s[0]) {
512	0	default:
513	0	break;
514	0	case 'f':
515		# if defined(FIPS_MODULE)
516		if (ossl_likely(strcmp("ips-indicator", s + 1) == 0)) {
517		/* KDF_PARAM_FIPS_APPROVED_INDICATOR */
518		if (ossl_unlikely(r->ind != NULL)) {
519		ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
520		"param %s is repeated", s);
521		return 0;
522		}
523		r->ind = (OSSL_PARAM *)p;
524		}
525		# endif
526	0	break;
527	0	case 's':
528	0	if (ossl_likely(strcmp("ize", s + 1) == 0)) {
529		/* KDF_PARAM_SIZE */
530	0	if (ossl_unlikely(r->size != NULL)) {
531	0	ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
532	0	"param %s is repeated", s);
533	0	return 0;
534	0	}
535	0	r->size = (OSSL_PARAM *)p;
536	0	}
537	0	}
538	0	return 1;
539	0	}
540		#endif
541		/* End of machine generated */
542
543		static int kdf_sshkdf_get_ctx_params(void *vctx, OSSL_PARAM params[])
544	0	{
545	0	KDF_SSHKDF ctx = (KDF_SSHKDF )vctx;
546	0	struct sshkdf_get_ctx_params_st p;
547
548	0	if (ctx == NULL \|\| !sshkdf_get_ctx_params_decoder(params, &p))
549	0	return 0;
550
551	0	if (p.size != NULL && !OSSL_PARAM_set_size_t(p.size, SIZE_MAX))
552	0	return 0;
553
554	0	if (!OSSL_FIPS_IND_GET_CTX_FROM_PARAM(ctx, p.ind))
555	0	return 0;
556	0	return 1;
557	0	}
558
559		static const OSSL_PARAM kdf_sshkdf_gettable_ctx_params(ossl_unused void ctx,
560		ossl_unused void *p_ctx)
561	0	{
562	0	return sshkdf_get_ctx_params_list;
563	0	}
564
565		const OSSL_DISPATCH ossl_kdf_sshkdf_functions[] = {
566		{ OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_sshkdf_new },
567		{ OSSL_FUNC_KDF_DUPCTX, (void(*)(void))kdf_sshkdf_dup },
568		{ OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_sshkdf_free },
569		{ OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_sshkdf_reset },
570		{ OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_sshkdf_derive },
571		{ OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
572		(void(*)(void))kdf_sshkdf_settable_ctx_params },
573		{ OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_sshkdf_set_ctx_params },
574		{ OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
575		(void(*)(void))kdf_sshkdf_gettable_ctx_params },
576		{ OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_sshkdf_get_ctx_params },
577		OSSL_DISPATCH_END
578		};
579
580		static int SSHKDF(const EVP_MD *evp_md,
581		const unsigned char *key, size_t key_len,
582		const unsigned char *xcghash, size_t xcghash_len,
583		const unsigned char *session_id, size_t session_id_len,
584		char type, unsigned char *okey, size_t okey_len)
585	0	{
586	0	EVP_MD_CTX *md = NULL;
587	0	unsigned char digest[EVP_MAX_MD_SIZE];
588	0	unsigned int dsize = 0;
589	0	size_t cursize = 0;
590	0	int ret = 0;
591
592	0	md = EVP_MD_CTX_new();
593	0	if (md == NULL)
594	0	return 0;
595
596	0	if (!EVP_DigestInit_ex(md, evp_md, NULL))
597	0	goto out;
598
599	0	if (!EVP_DigestUpdate(md, key, key_len))
600	0	goto out;
601
602	0	if (!EVP_DigestUpdate(md, xcghash, xcghash_len))
603	0	goto out;
604
605	0	if (!EVP_DigestUpdate(md, &type, 1))
606	0	goto out;
607
608	0	if (!EVP_DigestUpdate(md, session_id, session_id_len))
609	0	goto out;
610
611	0	if (!EVP_DigestFinal_ex(md, digest, &dsize))
612	0	goto out;
613
614	0	if (okey_len < dsize) {
615	0	memcpy(okey, digest, okey_len);
616	0	ret = 1;
617	0	goto out;
618	0	}
619
620	0	memcpy(okey, digest, dsize);
621
622	0	for (cursize = dsize; cursize < okey_len; cursize += dsize) {
623
624	0	if (!EVP_DigestInit_ex(md, evp_md, NULL))
625	0	goto out;
626
627	0	if (!EVP_DigestUpdate(md, key, key_len))
628	0	goto out;
629
630	0	if (!EVP_DigestUpdate(md, xcghash, xcghash_len))
631	0	goto out;
632
633	0	if (!EVP_DigestUpdate(md, okey, cursize))
634	0	goto out;
635
636	0	if (!EVP_DigestFinal_ex(md, digest, &dsize))
637	0	goto out;
638
639	0	if (okey_len < cursize + dsize) {
640	0	memcpy(okey + cursize, digest, okey_len - cursize);
641	0	ret = 1;
642	0	goto out;
643	0	}
644
645	0	memcpy(okey + cursize, digest, dsize);
646	0	}
647
648	0	ret = 1;
649
650	0	out:
651	0	EVP_MD_CTX_free(md);
652	0	OPENSSL_cleanse(digest, EVP_MAX_MD_SIZE);
653	0	return ret;
654	0	}