/*
- * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
* Copyright 2019 Red Hat, Inc.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
/*
* This implements https://csrc.nist.gov/publications/detail/sp/800-108/final
- * section 5.1 ("counter mode") in HMAC only. That document does not name the
- * KDFs it defines; the name is derived from
+ * section 5.1 ("counter mode") and section 5.2 ("feedback mode") in both HMAC
+ * and CMAC. That document does not name the KDFs it defines; the name is
+ * derived from
* https://csrc.nist.gov/Projects/Cryptographic-Algorithm-Validation-Program/Key-Derivation
*
- * Note that sections 5.2 ("feedback mode") and 5.3 ("double-pipeline mode")
- * are not implemented, though it would be possible to do so in the future.
- * CMAC mode is also not implemented; some plumbing would be required.
+ * Note that section 5.3 ("double-pipeline mode") is not implemented, though
+ * it would be possible to do so in the future.
*
* These versions all assume the counter is used. It would be relatively
* straightforward to expose a configuration handle should the need arise.
#include <openssl/hmac.h>
#include <openssl/kdf.h>
#include <openssl/params.h>
+#include <openssl/proverr.h>
#include "internal/cryptlib.h"
#include "crypto/evp.h"
#include "internal/numbers.h"
+#include "internal/endian.h"
#include "prov/implementations.h"
-#include "internal/provider_ctx.h"
-#include "internal/provider_util.h"
-#include "internal/providercommonerr.h"
+#include "prov/provider_ctx.h"
+#include "prov/provider_util.h"
+#include "prov/providercommon.h"
#include "e_os.h"
#define MIN(a, b) ((a) < (b)) ? (a) : (b)
+typedef enum {
+ COUNTER = 0,
+ FEEDBACK
+} kbkdf_mode;
+
/* Our context structure. */
typedef struct {
void *provctx;
+ kbkdf_mode mode;
EVP_MAC_CTX *ctx_init;
/* Names are lowercased versions of those found in SP800-108. */
size_t label_len;
unsigned char *context;
size_t context_len;
+ unsigned char *iv;
+ size_t iv_len;
+ int use_l;
+ int use_separator;
} KBKDF;
/* Definitions needed for typechecking. */
-static OSSL_OP_kdf_newctx_fn kbkdf_new;
-static OSSL_OP_kdf_freectx_fn kbkdf_free;
-static OSSL_OP_kdf_reset_fn kbkdf_reset;
-static OSSL_OP_kdf_derive_fn kbkdf_derive;
-static OSSL_OP_kdf_settable_ctx_params_fn kbkdf_settable_ctx_params;
-static OSSL_OP_kdf_set_ctx_params_fn kbkdf_set_ctx_params;
+static OSSL_FUNC_kdf_newctx_fn kbkdf_new;
+static OSSL_FUNC_kdf_freectx_fn kbkdf_free;
+static OSSL_FUNC_kdf_reset_fn kbkdf_reset;
+static OSSL_FUNC_kdf_derive_fn kbkdf_derive;
+static OSSL_FUNC_kdf_settable_ctx_params_fn kbkdf_settable_ctx_params;
+static OSSL_FUNC_kdf_set_ctx_params_fn kbkdf_set_ctx_params;
+static OSSL_FUNC_kdf_gettable_ctx_params_fn kbkdf_gettable_ctx_params;
+static OSSL_FUNC_kdf_get_ctx_params_fn kbkdf_get_ctx_params;
/* Not all platforms have htobe32(). */
static uint32_t be32(uint32_t host)
{
uint32_t big = 0;
- const union {
- long one;
- char little;
- } is_endian = { 1 };
+ DECLARE_IS_ENDIAN;
- if (!is_endian.little)
+ if (!IS_LITTLE_ENDIAN)
return host;
big |= (host & 0xff000000) >> 24;
return big;
}
+static void init(KBKDF *ctx)
+{
+ ctx->use_l = 1;
+ ctx->use_separator = 1;
+}
+
static void *kbkdf_new(void *provctx)
{
KBKDF *ctx;
+ if (!ossl_prov_is_running())
+ return NULL;
+
ctx = OPENSSL_zalloc(sizeof(*ctx));
if (ctx == NULL) {
ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
}
ctx->provctx = provctx;
+ init(ctx);
return ctx;
}
{
KBKDF *ctx = (KBKDF *)vctx;
- kbkdf_reset(ctx);
- OPENSSL_free(ctx);
+ if (ctx != NULL) {
+ kbkdf_reset(ctx);
+ OPENSSL_free(ctx);
+ }
}
static void kbkdf_reset(void *vctx)
{
KBKDF *ctx = (KBKDF *)vctx;
+ void *provctx = ctx->provctx;
EVP_MAC_CTX_free(ctx->ctx_init);
OPENSSL_clear_free(ctx->context, ctx->context_len);
OPENSSL_clear_free(ctx->label, ctx->label_len);
OPENSSL_clear_free(ctx->ki, ctx->ki_len);
+ OPENSSL_clear_free(ctx->iv, ctx->iv_len);
memset(ctx, 0, sizeof(*ctx));
+ ctx->provctx = provctx;
+ init(ctx);
}
-/* SP800-108 section 5.1. */
-static int kbkdf_derive_counter(EVP_MAC_CTX *ctx_init,
- unsigned char *label, size_t label_len,
- unsigned char *context, size_t context_len,
- unsigned char *k_i, size_t h, uint32_t l,
- unsigned char *ko, size_t ko_len)
+/* SP800-108 section 5.1 or section 5.2 depending on mode. */
+static int derive(EVP_MAC_CTX *ctx_init, kbkdf_mode mode, unsigned char *iv,
+ size_t iv_len, unsigned char *label, size_t label_len,
+ unsigned char *context, size_t context_len,
+ unsigned char *k_i, size_t h, uint32_t l, int has_separator,
+ unsigned char *ko, size_t ko_len)
{
int ret = 0;
EVP_MAC_CTX *ctx = NULL;
- size_t written = 0, to_write;
+ size_t written = 0, to_write, k_i_len = iv_len;
const unsigned char zero = 0;
uint32_t counter, i;
+ /*
+ * From SP800-108:
+ * The fixed input data is a concatenation of a Label,
+ * a separation indicator 0x00, the Context, and L.
+ * One or more of these fixed input data fields may be omitted.
+ *
+ * has_separator == 0 means that the separator is omitted.
+ * Passing a value of l == 0 means that L is omitted.
+ * The Context and L are omitted automatically if a NULL buffer is passed.
+ */
+ int has_l = (l != 0);
+
+ /* Setup K(0) for feedback mode. */
+ if (iv_len > 0)
+ memcpy(k_i, iv, iv_len);
for (counter = 1; written < ko_len; counter++) {
i = be32(counter);
if (ctx == NULL)
goto done;
+ /* Perform feedback, if appropriate. */
+ if (mode == FEEDBACK && !EVP_MAC_update(ctx, k_i, k_i_len))
+ goto done;
+
if (!EVP_MAC_update(ctx, (unsigned char *)&i, 4)
|| !EVP_MAC_update(ctx, label, label_len)
- || !EVP_MAC_update(ctx, &zero, 1)
+ || (has_separator && !EVP_MAC_update(ctx, &zero, 1))
|| !EVP_MAC_update(ctx, context, context_len)
- || !EVP_MAC_update(ctx, (unsigned char *)&l, 4)
+ || (has_l && !EVP_MAC_update(ctx, (unsigned char *)&l, 4))
|| !EVP_MAC_final(ctx, k_i, NULL, h))
goto done;
memcpy(ko + written, k_i, MIN(to_write, h));
written += h;
+ k_i_len = h;
EVP_MAC_CTX_free(ctx);
ctx = NULL;
}
return ret;
}
-static int kbkdf_derive(void *vctx, unsigned char *key, size_t keylen)
+static int kbkdf_derive(void *vctx, unsigned char *key, size_t keylen,
+ const OSSL_PARAM params[])
{
KBKDF *ctx = (KBKDF *)vctx;
int ret = 0;
unsigned char *k_i = NULL;
- uint32_t l = be32(keylen * 8);
+ uint32_t l = 0;
size_t h = 0;
- /* Label and Context are permitted to be empty. Check everything else. */
+ if (!ossl_prov_is_running() || !kbkdf_set_ctx_params(ctx, params))
+ return 0;
+
+ /* label, context, and iv are permitted to be empty. Check everything
+ * else. */
if (ctx->ctx_init == NULL) {
if (ctx->ki_len == 0 || ctx->ki == NULL) {
ERR_raise(ERR_LIB_PROV, PROV_R_NO_KEY_SET);
return 0;
}
- /* Could either be missing MAC or missing message digest -
- * arbitrarily, I pick this one. */
+ /* Could either be missing MAC or missing message digest or missing
+ * cipher - arbitrarily, I pick this one. */
ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_MAC);
return 0;
}
- h = EVP_MAC_size(ctx->ctx_init);
+ /* Fail if the output length is zero */
+ if (keylen == 0) {
+ ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
+ return 0;
+ }
+
+ h = EVP_MAC_CTX_get_mac_size(ctx->ctx_init);
if (h == 0)
goto done;
+ if (ctx->iv_len != 0 && ctx->iv_len != h) {
+ ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_SEED_LENGTH);
+ goto done;
+ }
+
+ if (ctx->use_l != 0)
+ l = be32(keylen * 8);
k_i = OPENSSL_zalloc(h);
if (k_i == NULL)
goto done;
- ret = kbkdf_derive_counter(
- ctx->ctx_init, ctx->label, ctx->label_len, ctx->context,
- ctx->context_len, k_i, h, l, key, keylen);
+ ret = derive(ctx->ctx_init, ctx->mode, ctx->iv, ctx->iv_len, ctx->label,
+ ctx->label_len, ctx->context, ctx->context_len, k_i, h, l,
+ ctx->use_separator, key, keylen);
done:
if (ret != 1)
OPENSSL_cleanse(key, keylen);
static int kbkdf_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
KBKDF *ctx = (KBKDF *)vctx;
- OPENSSL_CTX *libctx = PROV_LIBRARY_CONTEXT_OF(ctx->provctx);
+ OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
const OSSL_PARAM *p;
- OSSL_PARAM mparams[2];
if (!ossl_prov_macctx_load_from_params(&ctx->ctx_init, params, NULL,
NULL, NULL, libctx))
return 0;
else if (ctx->ctx_init != NULL
- && !EVP_MAC_is_a(EVP_MAC_CTX_mac(ctx->ctx_init),
- OSSL_MAC_NAME_HMAC)) {
+ && !EVP_MAC_is_a(EVP_MAC_CTX_mac(ctx->ctx_init),
+ OSSL_MAC_NAME_HMAC)
+ && !EVP_MAC_is_a(EVP_MAC_CTX_mac(ctx->ctx_init),
+ OSSL_MAC_NAME_CMAC)) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_MAC);
return 0;
}
+ p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_MODE);
+ if (p != NULL && strncasecmp("counter", p->data, p->data_size) == 0) {
+ ctx->mode = COUNTER;
+ } else if (p != NULL
+ && strncasecmp("feedback", p->data, p->data_size) == 0) {
+ ctx->mode = FEEDBACK;
+ } else if (p != NULL) {
+ ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_MODE);
+ return 0;
+ }
+
p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KEY);
if (p != NULL && !kbkdf_set_buffer(&ctx->ki, &ctx->ki_len, p))
return 0;
if (p != NULL && !kbkdf_set_buffer(&ctx->context, &ctx->context_len, p))
return 0;
- /* Set up digest context, if we can. */
- if (ctx->ctx_init != NULL && ctx->ki_len != 0) {
- mparams[0] = OSSL_PARAM_construct_octet_string(OSSL_MAC_PARAM_KEY,
- ctx->ki, ctx->ki_len);
- mparams[1] = OSSL_PARAM_construct_end();
+ p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SEED);
+ if (p != NULL && !kbkdf_set_buffer(&ctx->iv, &ctx->iv_len, p))
+ return 0;
- if (!EVP_MAC_CTX_set_params(ctx->ctx_init, mparams)
- || !EVP_MAC_init(ctx->ctx_init))
- return 0;
- }
+ p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KBKDF_USE_L);
+ if (p != NULL && !OSSL_PARAM_get_int(p, &ctx->use_l))
+ return 0;
+
+ p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KBKDF_USE_SEPARATOR);
+ if (p != NULL && !OSSL_PARAM_get_int(p, &ctx->use_separator))
+ return 0;
+ /* Set up digest context, if we can. */
+ if (ctx->ctx_init != NULL && ctx->ki_len != 0
+ && !EVP_MAC_init(ctx->ctx_init, ctx->ki, ctx->ki_len, NULL))
+ return 0;
return 1;
}
-static const OSSL_PARAM *kbkdf_settable_ctx_params(void)
+static const OSSL_PARAM *kbkdf_settable_ctx_params(ossl_unused void *ctx,
+ ossl_unused void *provctx)
{
static const OSSL_PARAM known_settable_ctx_params[] = {
OSSL_PARAM_octet_string(OSSL_KDF_PARAM_INFO, NULL, 0),
OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
OSSL_PARAM_octet_string(OSSL_KDF_PARAM_KEY, NULL, 0),
+ OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SEED, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0),
+ OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_CIPHER, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_MAC, NULL, 0),
-
+ OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_MODE, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
+ OSSL_PARAM_int(OSSL_KDF_PARAM_KBKDF_USE_L, NULL),
+ OSSL_PARAM_int(OSSL_KDF_PARAM_KBKDF_USE_SEPARATOR, NULL),
OSSL_PARAM_END,
};
return known_settable_ctx_params;
return OSSL_PARAM_set_size_t(p, SIZE_MAX);
}
-static const OSSL_PARAM *kbkdf_gettable_ctx_params(void)
+static const OSSL_PARAM *kbkdf_gettable_ctx_params(ossl_unused void *ctx,
+ ossl_unused void *provctx)
{
static const OSSL_PARAM known_gettable_ctx_params[] =
{ OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL), OSSL_PARAM_END };
return known_gettable_ctx_params;
}
-const OSSL_DISPATCH kdf_kbkdf_functions[] = {
+const OSSL_DISPATCH ossl_kdf_kbkdf_functions[] = {
{ OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kbkdf_new },
{ OSSL_FUNC_KDF_FREECTX, (void(*)(void))kbkdf_free },
{ OSSL_FUNC_KDF_RESET, (void(*)(void))kbkdf_reset },