* Result(0) = empty bit string (i.e., the null string).
* For i = 1 to reps, do the following:
* Increment counter by 1.
- * Result(i) = Result(i – 1) || H(counter || Z || FixedInfo).
+ * Result(i) = Result(i - 1) || H(counter || Z || FixedInfo).
* DKM = LeftmostBits(Result(reps), L))
*
* NOTES:
#include <openssl/hmac.h>
#include <openssl/evp.h>
#include <openssl/kdf.h>
+#include <openssl/core_names.h>
+#include <openssl/params.h>
#include "internal/cryptlib.h"
#include "internal/evp_int.h"
#include "kdf_local.h"
struct evp_kdf_impl_st {
- const EVP_MAC *mac; /* H(x) = HMAC_hash OR H(x) = KMAC */
+ EVP_MAC *mac; /* H(x) = HMAC_hash OR H(x) = KMAC */
const EVP_MD *md; /* H(x) = hash OR when H(x) = HMAC_hash */
unsigned char *secret;
size_t secret_len;
/*
* Refer to https://csrc.nist.gov/publications/detail/sp/800-56c/rev-1/final
* Section 4. One-Step Key Derivation using H(x) = hash(x)
+ * Note: X9.63 also uses this code with the only difference being that the
+ * counter is appended to the secret 'z'.
+ * i.e.
+ * result[i] = Hash(counter || z || info) for One Step OR
+ * result[i] = Hash(z || counter || info) for X9.63.
*/
static int SSKDF_hash_kdm(const EVP_MD *kdf_md,
const unsigned char *z, size_t z_len,
const unsigned char *info, size_t info_len,
+ unsigned int append_ctr,
unsigned char *derived_key, size_t derived_key_len)
{
int ret = 0, hlen;
c[3] = (unsigned char)(counter & 0xff);
if (!(EVP_MD_CTX_copy_ex(ctx, ctx_init)
- && EVP_DigestUpdate(ctx, c, sizeof(c))
+ && (append_ctr || EVP_DigestUpdate(ctx, c, sizeof(c)))
&& EVP_DigestUpdate(ctx, z, z_len)
+ && (!append_ctr || EVP_DigestUpdate(ctx, c, sizeof(c)))
&& EVP_DigestUpdate(ctx, info, info_len)))
goto end;
if (len >= out_len) {
size_t custom_len, size_t kmac_out_len,
size_t derived_key_len, unsigned char **out)
{
+ OSSL_PARAM params[2];
+
/* Only KMAC has custom data - so return if not KMAC */
if (custom == NULL)
return 1;
- if (EVP_MAC_ctrl(ctx, EVP_MAC_CTRL_SET_CUSTOM, custom, custom_len) <= 0)
+ params[0] = OSSL_PARAM_construct_octet_string(OSSL_MAC_PARAM_CUSTOM,
+ (void *)custom, custom_len);
+ params[1] = OSSL_PARAM_construct_end();
+
+ if (!EVP_MAC_CTX_set_params(ctx, params))
return 0;
/* By default only do one iteration if kmac_out_len is not specified */
|| kmac_out_len == 64))
return 0;
- if (EVP_MAC_ctrl(ctx, EVP_MAC_CTRL_SET_SIZE, kmac_out_len) <= 0)
+ params[0] = OSSL_PARAM_construct_size_t(OSSL_MAC_PARAM_SIZE,
+ &kmac_out_len);
+
+ if (EVP_MAC_CTX_set_params(ctx, params) <= 0)
return 0;
/*
* H(x) = HMAC-hash(salt, x) OR
* H(x) = KMAC#(salt, x, outbits, CustomString='KDF')
*/
-static int SSKDF_mac_kdm(const EVP_MAC *kdf_mac, const EVP_MD *hmac_md,
+static int SSKDF_mac_kdm(EVP_MAC *kdf_mac, const EVP_MD *hmac_md,
const unsigned char *kmac_custom,
size_t kmac_custom_len, size_t kmac_out_len,
const unsigned char *salt, size_t salt_len,
unsigned char *out = derived_key;
EVP_MAC_CTX *ctx = NULL, *ctx_init = NULL;
unsigned char *mac = mac_buf, *kmac_buffer = NULL;
+ OSSL_PARAM params[3];
+ size_t params_n = 0;
if (z_len > SSKDF_MAX_INLEN || info_len > SSKDF_MAX_INLEN
|| derived_key_len > SSKDF_MAX_INLEN
|| derived_key_len == 0)
return 0;
- ctx = EVP_MAC_CTX_new(kdf_mac);
ctx_init = EVP_MAC_CTX_new(kdf_mac);
- if (ctx == NULL || ctx_init == NULL)
- goto end;
- if (hmac_md != NULL &&
- EVP_MAC_ctrl(ctx_init, EVP_MAC_CTRL_SET_MD, hmac_md) <= 0)
+ if (ctx_init == NULL)
goto end;
- if (EVP_MAC_ctrl(ctx_init, EVP_MAC_CTRL_SET_KEY, salt, salt_len) <= 0)
+ if (hmac_md != NULL) {
+ const char *mdname = EVP_MD_name(hmac_md);
+ params[params_n++] =
+ OSSL_PARAM_construct_utf8_string(OSSL_MAC_PARAM_DIGEST,
+ (char *)mdname,
+ strlen(mdname) + 1);
+ }
+ params[params_n++] =
+ OSSL_PARAM_construct_octet_string(OSSL_MAC_PARAM_KEY, (void *)salt,
+ salt_len);
+ params[params_n] = OSSL_PARAM_construct_end();
+
+ if (!EVP_MAC_CTX_set_params(ctx_init, params))
goto end;
if (!kmac_init(ctx_init, kmac_custom, kmac_custom_len, kmac_out_len,
c[2] = (unsigned char)((counter >> 8) & 0xff);
c[3] = (unsigned char)(counter & 0xff);
- if (!(EVP_MAC_CTX_copy(ctx, ctx_init)
+ ctx = EVP_MAC_CTX_dup(ctx_init);
+ if (!(ctx != NULL
&& EVP_MAC_update(ctx, c, sizeof(c))
&& EVP_MAC_update(ctx, z, z_len)
&& EVP_MAC_update(ctx, info, info_len)))
goto end;
if (len >= out_len) {
- if (!EVP_MAC_final(ctx, out, NULL))
+ if (!EVP_MAC_final(ctx, out, NULL, len))
goto end;
out += out_len;
len -= out_len;
if (len == 0)
break;
} else {
- if (!EVP_MAC_final(ctx, mac, NULL))
+ if (!EVP_MAC_final(ctx, mac, NULL, len))
goto end;
memcpy(out, mac, len);
break;
}
+ EVP_MAC_CTX_free(ctx);
+ ctx = NULL;
}
ret = 1;
end:
- OPENSSL_free(kmac_buffer);
+ if (kmac_buffer != NULL)
+ OPENSSL_clear_free(kmac_buffer, kmac_out_len);
+ else
+ OPENSSL_cleanse(mac_buf, sizeof(mac_buf));
+
EVP_MAC_CTX_free(ctx);
EVP_MAC_CTX_free(ctx_init);
- OPENSSL_cleanse(mac, sizeof(mac));
return ret;
}
OPENSSL_clear_free(impl->secret, impl->secret_len);
OPENSSL_clear_free(impl->info, impl->info_len);
OPENSSL_clear_free(impl->salt, impl->salt_len);
+ EVP_MAC_free(impl->mac);
+#if 0 /* TODO(3.0) When we switch to fetched MDs */
+ EVP_MD_meth_free(impl->md);
+#endif
memset(impl, 0, sizeof(*impl));
}
static int sskdf_ctrl(EVP_KDF_IMPL *impl, int cmd, va_list args)
{
const EVP_MD *md;
- const EVP_MAC *mac;
switch (cmd) {
case EVP_KDF_CTRL_SET_KEY:
if (md == NULL)
return 0;
+#if 0 /* TODO(3.0) When we switch to fetched MDs */
+ EVP_MD_meth_free(impl->md);
+#endif
impl->md = md;
return 1;
case EVP_KDF_CTRL_SET_MAC:
- mac = va_arg(args, const EVP_MAC *);
- if (mac == NULL)
- return 0;
+ {
+ const char *name;
+ EVP_MAC *mac;
- impl->mac = mac;
- return 1;
+ name = va_arg(args, const char *);
+ if (name == NULL)
+ return 0;
+
+ EVP_MAC_free(impl->mac);
+ impl->mac = NULL;
+
+ /*
+ * TODO(3.0) add support for OPENSSL_CTX and properties in KDFs
+ */
+ mac = EVP_MAC_fetch(NULL, name, NULL);
+ if (mac == NULL)
+ return 0;
+ impl->mac = mac;
+ return 1;
+ }
case EVP_KDF_CTRL_SET_SALT:
return sskdf_set_buffer(args, &impl->salt, &impl->salt_len);
}
}
-/* Pass a mac to a ctrl */
-static int sskdf_mac2ctrl(EVP_KDF_IMPL *impl,
- int (*ctrl)(EVP_KDF_IMPL *impl, int cmd, va_list args),
- int cmd, const char *mac_name)
-{
- const EVP_MAC *mac;
-
- if (mac_name == NULL || (mac = EVP_get_macbyname(mac_name)) == NULL) {
- KDFerr(KDF_F_SSKDF_MAC2CTRL, KDF_R_INVALID_MAC_TYPE);
- return 0;
- }
- return call_ctrl(ctrl, impl, cmd, mac);
-}
-
static int sskdf_ctrl_str(EVP_KDF_IMPL *impl, const char *type,
const char *value)
{
return kdf_md2ctrl(impl, sskdf_ctrl, EVP_KDF_CTRL_SET_MD, value);
if (strcmp(type, "mac") == 0)
- return sskdf_mac2ctrl(impl, sskdf_ctrl, EVP_KDF_CTRL_SET_MAC, value);
+ return kdf_str2ctrl(impl, sskdf_ctrl, EVP_KDF_CTRL_SET_MAC, value);
if (strcmp(type, "salt") == 0)
return kdf_str2ctrl(impl, sskdf_ctrl, EVP_KDF_CTRL_SET_SALT, value);
int ret;
const unsigned char *custom = NULL;
size_t custom_len = 0;
- int nid;
+ const char *macname;
int default_salt_len;
- nid = EVP_MAC_nid(impl->mac);
- if (nid == EVP_MAC_HMAC) {
+ /*
+ * TODO(3.0) investigate the necessity to have all these controls.
+ * Why does KMAC require a salt length that's shorter than the MD
+ * block size?
+ */
+ macname = EVP_MAC_name(impl->mac);
+ if (strcmp(macname, OSSL_MAC_NAME_HMAC) == 0) {
/* H(x) = HMAC(x, salt, hash) */
if (impl->md == NULL) {
KDFerr(KDF_F_SSKDF_DERIVE, KDF_R_MISSING_MESSAGE_DIGEST);
default_salt_len = EVP_MD_block_size(impl->md);
if (default_salt_len <= 0)
return 0;
- } else if (nid == EVP_MAC_KMAC128 || nid == EVP_MAC_KMAC256) {
+ } else if (strcmp(macname, OSSL_MAC_NAME_KMAC128) == 0
+ || strcmp(macname, OSSL_MAC_NAME_KMAC256) == 0) {
/* H(x) = KMACzzz(x, salt, custom) */
custom = kmac_custom_str;
custom_len = sizeof(kmac_custom_str);
- if (nid == EVP_MAC_KMAC128)
+ if (strcmp(macname, OSSL_MAC_NAME_KMAC128) == 0)
default_salt_len = SSKDF_KMAC128_DEFAULT_SALT_SIZE;
else
default_salt_len = SSKDF_KMAC256_DEFAULT_SALT_SIZE;
return 0;
}
return SSKDF_hash_kdm(impl->md, impl->secret, impl->secret_len,
- impl->info, impl->info_len, key, keylen);
+ impl->info, impl->info_len, 0, key, keylen);
}
}
-const EVP_KDF_METHOD ss_kdf_meth = {
+static int x963kdf_derive(EVP_KDF_IMPL *impl, unsigned char *key, size_t keylen)
+{
+ if (impl->secret == NULL) {
+ KDFerr(KDF_F_X963KDF_DERIVE, KDF_R_MISSING_SECRET);
+ return 0;
+ }
+
+ if (impl->mac != NULL) {
+ KDFerr(KDF_F_X963KDF_DERIVE, KDF_R_NOT_SUPPORTED);
+ return 0;
+ } else {
+ /* H(x) = hash */
+ if (impl->md == NULL) {
+ KDFerr(KDF_F_X963KDF_DERIVE, KDF_R_MISSING_MESSAGE_DIGEST);
+ return 0;
+ }
+ return SSKDF_hash_kdm(impl->md, impl->secret, impl->secret_len,
+ impl->info, impl->info_len, 1, key, keylen);
+ }
+}
+
+const EVP_KDF ss_kdf_meth = {
EVP_KDF_SS,
sskdf_new,
sskdf_free,
sskdf_size,
sskdf_derive
};
+
+const EVP_KDF x963_kdf_meth = {
+ EVP_KDF_X963,
+ sskdf_new,
+ sskdf_free,
+ sskdf_reset,
+ sskdf_ctrl,
+ sskdf_ctrl_str,
+ sskdf_size,
+ x963kdf_derive
+};
projects / openssl.git / blobdiff