X-Git-Url: https://git.openssl.org/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fkdf%2Fsskdf.c;h=916a06e5a1ebbbcc72b89d22c0cd9e6cb3619263;hp=e999b54b773ed2ba3198a16dfaf1510c9a40387c;hb=703170d4b9da1b3adc0e4d87719a5156080b2dca;hpb=9537fe5757bb07761fa275d779bbd40bcf5530e4 diff --git a/crypto/kdf/sskdf.c b/crypto/kdf/sskdf.c index e999b54b77..916a06e5a1 100644 --- a/crypto/kdf/sskdf.c +++ b/crypto/kdf/sskdf.c @@ -17,7 +17,7 @@ * 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: @@ -40,12 +40,14 @@ #include #include #include +#include +#include #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; @@ -66,10 +68,16 @@ static const unsigned char kmac_custom_str[] = { 0x4B, 0x44, 0x46 }; /* * 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; @@ -104,8 +112,9 @@ static int SSKDF_hash_kdm(const EVP_MD *kdf_md, 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) { @@ -134,11 +143,17 @@ static int kmac_init(EVP_MAC_CTX *ctx, const unsigned char *custom, 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)) + 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 */ @@ -153,7 +168,10 @@ static int kmac_init(EVP_MAC_CTX *ctx, const unsigned char *custom, || kmac_out_len == 64)) return 0; - if (!EVP_MAC_ctrl(ctx, EVP_MAC_CTRL_SET_SIZE, kmac_out_len)) + 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; /* @@ -174,7 +192,7 @@ static int kmac_init(EVP_MAC_CTX *ctx, const unsigned char *custom, * 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, @@ -189,21 +207,31 @@ static int SSKDF_mac_kdm(const EVP_MAC *kdf_mac, const EVP_MD *hmac_md, 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)) + if (ctx_init == NULL) goto end; - if (!EVP_MAC_ctrl(ctx_init, EVP_MAC_CTRL_SET_KEY, salt, salt_len)) + 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, @@ -226,31 +254,37 @@ static int SSKDF_mac_kdm(const EVP_MAC *kdf_mac, const EVP_MD *hmac_md, 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; } @@ -268,6 +302,10 @@ static void sskdf_reset(EVP_KDF_IMPL *impl) 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)); } @@ -299,7 +337,6 @@ static int sskdf_set_buffer(va_list args, unsigned char **out, size_t *out_len) 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: @@ -313,17 +350,34 @@ static int sskdf_ctrl(EVP_KDF_IMPL *impl, int cmd, va_list args) 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); @@ -336,20 +390,6 @@ static int sskdf_ctrl(EVP_KDF_IMPL *impl, int cmd, va_list args) } } -/* 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) { @@ -373,7 +413,7 @@ static int sskdf_ctrl_str(EVP_KDF_IMPL *impl, const char *type, 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); @@ -418,11 +458,16 @@ static int sskdf_derive(EVP_KDF_IMPL *impl, unsigned char *key, size_t keylen) 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); @@ -431,11 +476,12 @@ static int sskdf_derive(EVP_KDF_IMPL *impl, unsigned char *key, size_t keylen) 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; @@ -465,11 +511,32 @@ static int sskdf_derive(EVP_KDF_IMPL *impl, unsigned char *key, size_t keylen) 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, @@ -479,3 +546,14 @@ const EVP_KDF_METHOD ss_kdf_meth = { 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 +};