/* * Copyright (c) 2019 Andreas Schneider * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #ifndef _GNUTLS_HELPERS_H #define _GNUTLS_HELPERS_H #include #include "libcli/util/ntstatus.h" #include "libcli/util/werror.h" #include "lib/util/data_blob.h" #ifdef DOXYGEN /** * @brief Convert a gnutls error code to a corresponding NTSTATUS. * * @param[in] gnutls_rc The GnuTLS return code. * * @param[in] blocked_status The NTSTATUS return code which should be returned * in case the e.g. the cipher might be blocked due * to FIPS mode. * * @return A corresponding NTSTATUS code. */ NTSTATUS gnutls_error_to_ntstatus(int gnutls_rc, NTSTATUS blocked_status); #else NTSTATUS _gnutls_error_to_ntstatus(int gnutls_rc, NTSTATUS blocked_status, const char *function, const char *location); #define gnutls_error_to_ntstatus(gnutls_rc, blocked_status) \ _gnutls_error_to_ntstatus(gnutls_rc, \ blocked_status, \ __FUNCTION__, \ __location__) #endif #ifdef DOXYGEN /** * @brief Convert a gnutls error code to a corresponding WERROR. * * @param[in] gnutls_rc The GnuTLS return code. * * @param[in] blocked_werr The WERROR code which should be returned if e.g * the cipher we want to used it not allowed to be * used because of FIPS mode. * * @return A corresponding WERROR code. */ WERROR gnutls_error_to_werror(int gnutls_rc, WERROR blocked_werr); #else WERROR _gnutls_error_to_werror(int gnutls_rc, WERROR blocked_werr, const char *function, const char *location); #define gnutls_error_to_werror(gnutls_rc, blocked_werr) \ _gnutls_error_to_werror(gnutls_rc, \ blocked_werr, \ __FUNCTION__, \ __location__) #endif enum samba_gnutls_direction { SAMBA_GNUTLS_ENCRYPT, SAMBA_GNUTLS_DECRYPT }; /** * @brief Encrypt or decrypt a data blob using RC4 with a key and salt. * * One of the key input should be a session key and the other a confounder * (aka salt). Which one depends on the implementation details of the * protocol. * * @param[in] key_input1 Either a session_key or a confounder. * * @param[in] key_input2 Either a session_key or a confounder. * * @param[in] data The data blob to either encrypt or decrypt. The data * will be encrypted or decrypted in place. * * @param[in] encrypt The encryption direction. * * @return A gnutls error code. */ int samba_gnutls_arcfour_confounded_md5(const DATA_BLOB *key_input1, const DATA_BLOB *key_input2, DATA_BLOB *data, enum samba_gnutls_direction encrypt); /** * @brief Encrypted a secret plaintext using AEAD_AES_256_CBC_HMAC_SHA512 and * the session key. * * This encrypts a secret plaintext using AEAD_AES_256_CBC_HMAC_SHA512 with a * key (can be the session key or PBKDF2 password). This is used in SAMR and * LSA. * * @param mem_ctx The memory context to allocate the cipher text pointer. * * @param plaintext The secret to encrypt * * @param cek The content encryption key to encrypt the secret. * * @param key_salt The salt used to calculate the encryption key. * * @param key_salt The salt used to calculate the mac key. * @param iv The initialization vector used for the encryption. * * @param pciphertext A pointer to store the cipher text. * * @param pauth_tag[64] An array to store the auth tag. * * @return NT_STATUS_OK on success, an nt status error code otherwise. */ NTSTATUS samba_gnutls_aead_aes_256_cbc_hmac_sha512_encrypt(TALLOC_CTX *mem_ctx, const DATA_BLOB *plaintext, const DATA_BLOB *cek, const DATA_BLOB *key_salt, const DATA_BLOB *mac_salt, const DATA_BLOB *iv, DATA_BLOB *pciphertext, uint8_t pauth_tag[64]); /** * @brief Decypt cipher text using AEAD_AES_256_CBC_HMAC_SHA512 and the session * key. * * This decrypts the cipher text using AEAD_AES_256_CBC_HMAC_SHA512 with the * given content decryption key key. The plaintext will be zeroed as soon as the * data blob is freed. * * @param mem_ctx The memory context to allocate the plaintext on. * * @param ciphertext The cipher text to decrypt. * * @param cdk The content decryption key. * * @param key_salt The salt used to calculate the encryption key. * * @param key_salt The salt used to calculate the mac key. * @param iv The initialization vector used for the encryption. * * @param auth_tag[64] The authentication blob to be verified. * * @param pplaintext A pointer to a DATA_BLOB to store the plaintext. * * @return NT_STATUS_OK on success, an nt status error code otherwise. */ NTSTATUS samba_gnutls_aead_aes_256_cbc_hmac_sha512_decrypt(TALLOC_CTX *mem_ctx, const DATA_BLOB *ciphertext, const DATA_BLOB *cdk, const DATA_BLOB *key_salt, const DATA_BLOB *mac_salt, const DATA_BLOB *iv, const uint8_t auth_tag[64], DATA_BLOB *pplaintext); /** * @brief Check if weak crypto is allowed. * * @return true if weak crypo is allowed, false otherwise. */ bool samba_gnutls_weak_crypto_allowed(void); /** * @brief Derive a key using the NIST SP 800‐108 algorithm. * * The details of the algorithm can be found at * https://csrc.nist.gov/pubs/sp/800/108/r1/final. * * @param KI The key‐derivation key used as input. * * @param KI_len The length of the key‐derivation key. * * @param FixedData If non‐NULL, specifies fixed data to be used in place of * that constructed from the Label and Context parameters. * * @param FixedData_len The length of the fixed data, if it is present. * * @param Label A label that identifies the purpose for the derived key. * Ignored if FixedData is non‐NULL. * * @param Label_len The length of the label. * * @param Context Information related to the derived key. Ignored if * FixedData is non‐NULL. * * @param Context_len The length of the context data. * * @param algorithm The HMAC algorithm to use. * * @param KO A buffer to receive the derived key. * * @param KO_len The length of the key to be derived. * * @return NT_STATUS_OK on success, an NT status error code otherwise. */ NTSTATUS samba_gnutls_sp800_108_derive_key( const uint8_t *KI, size_t KI_len, const uint8_t *FixedData, size_t FixedData_len, const uint8_t *Label, size_t Label_len, const uint8_t *Context, size_t Context_len, const gnutls_mac_algorithm_t algorithm, uint8_t *KO, size_t KO_len); #ifndef HAVE_GNUTLS_CB_TLS_SERVER_END_POINT int legacy_gnutls_server_end_point_cb(gnutls_session_t session, bool is_server, gnutls_datum_t * cb); #endif /* HAVE_GNUTLS_CB_TLS_SERVER_END_POINT */ #endif /* _GNUTLS_HELPERS_H */