/*
 *
 * Copyright 2015, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#ifndef GRPC_INTERNAL_CORE_TSI_SSL_TRANSPORT_SECURITY_H
#define GRPC_INTERNAL_CORE_TSI_SSL_TRANSPORT_SECURITY_H

#include "src/core/tsi/transport_security_interface.h"

#ifdef __cplusplus
extern "C" {
#endif

/* Value for the TSI_CERTIFICATE_TYPE_PEER_PROPERTY property for X509 certs. */
#define TSI_X509_CERTIFICATE_TYPE "X509"

/* This property is of type TSI_PEER_PROPERTY_STRING.  */
#define TSI_X509_SUBJECT_COMMON_NAME_PEER_PROPERTY "x509_subject_common_name"
#define TSI_X509_SUBJECT_ALTERNATIVE_NAME_PEER_PROPERTY \
  "x509_subject_alternative_name"

#define TSI_SSL_ALPN_SELECTED_PROTOCOL "ssl_alpn_selected_protocol"

/* --- tsi_ssl_handshaker_factory object ---

   This object creates tsi_handshaker objects implemented in terms of the
   TLS 1.2 specificiation.  */

typedef struct tsi_ssl_handshaker_factory tsi_ssl_handshaker_factory;

/* Creates a client handshaker factory.
   - pem_private_key is the buffer containing the PEM encoding of the client's
     private key. This parameter can be NULL if the client does not have a
     private key.
   - pem_private_key_size is the size of the associated buffer.
   - pem_cert_chain is the buffer containing the PEM encoding of the client's
     certificate chain. This parameter can be NULL if the client does not have
     a certificate chain.
   - pem_cert_chain_size is the size of the associated buffer.
   - pem_roots_cert is the buffer containing the PEM encoding of the server
     root certificates. This parameter cannot be NULL.
   - pem_roots_cert_size is the size of the associated buffer.
   - cipher_suites contains an optional list of the ciphers that the client
     supports. The format of this string is described in:
     https://www.openssl.org/docs/apps/ciphers.html.
     This parameter can be set to NULL to use the default set of ciphers.
     TODO(jboeuf): Revisit the format of this parameter.
   - alpn_protocols is an array containing the protocol names that the
     handshakers created with this factory support. This parameter can be NULL.
   - alpn_protocols_lengths is an array containing the lengths of the alpn
     protocols specified in alpn_protocols. This parameter can be NULL.
   - num_alpn_protocols is the number of alpn protocols and associated lengths
     specified. If this parameter is 0, the other alpn parameters must be NULL.
   - factory is the address of the factory pointer to be created.

   - This method returns TSI_OK on success or TSI_INVALID_PARAMETER in the case
     where a parameter is invalid.  */
tsi_result tsi_create_ssl_client_handshaker_factory(
    const unsigned char *pem_private_key, size_t pem_private_key_size,
    const unsigned char *pem_cert_chain, size_t pem_cert_chain_size,
    const unsigned char *pem_root_certs, size_t pem_root_certs_size,
    const char *cipher_suites, const unsigned char **alpn_protocols,
    const unsigned char *alpn_protocols_lengths, uint16_t num_alpn_protocols,
    tsi_ssl_handshaker_factory **factory);

/* Creates a server handshaker factory.
   - version indicates which version of the specification to use.
   - pem_private_keys is an array containing the PEM encoding of the server's
     private keys.  This parameter cannot be NULL. The size of the array is
     given by the key_cert_pair_count parameter.
   - pem_private_keys_sizes is the array containing the sizes of the associated
     buffers.
   - pem_cert_chains is an array containing the PEM encoding of the server's
     cert chains.  This parameter cannot be NULL. The size of the array is
     given by the key_cert_pair_count parameter.
   - pem_cert_chains_sizes is the array containing the sizes of the associated
     buffers.
   - key_cert_pair_count indicates the number of items in the private_key_files
     and cert_chain_files parameters.
   - pem_client_roots is the buffer containing the PEM encoding of the client
     root certificates. This parameter may be NULL in which case the server will
     not authenticate the client. If not NULL, the force_client_auth parameter
     specifies if the server will accept only authenticated clients or both
     authenticated and non-authenticated clients.
   - pem_client_root_certs_size is the size of the associated buffer.
   - force_client_auth, if set to non-zero will force the client to authenticate
     with an SSL cert. Note that this option is ignored if pem_client_root_certs
     is NULL or pem_client_roots_certs_size is 0
   - cipher_suites contains an optional list of the ciphers that the server
     supports. The format of this string is described in:
     https://www.openssl.org/docs/apps/ciphers.html.
     This parameter can be set to NULL to use the default set of ciphers.
     TODO(jboeuf): Revisit the format of this parameter.
   - alpn_protocols is an array containing the protocol names that the
     handshakers created with this factory support. This parameter can be NULL.
   - alpn_protocols_lengths is an array containing the lengths of the alpn
     protocols specified in alpn_protocols. This parameter can be NULL.
   - num_alpn_protocols is the number of alpn protocols and associated lengths
     specified. If this parameter is 0, the other alpn parameters must be NULL.
   - factory is the address of the factory pointer to be created.

   - This method returns TSI_OK on success or TSI_INVALID_PARAMETER in the case
     where a parameter is invalid.  */
tsi_result tsi_create_ssl_server_handshaker_factory(
    const unsigned char **pem_private_keys,
    const size_t *pem_private_keys_sizes, const unsigned char **pem_cert_chains,
    const size_t *pem_cert_chains_sizes, size_t key_cert_pair_count,
    const unsigned char *pem_client_root_certs,
    size_t pem_client_root_certs_size, int force_client_auth,
    const char *cipher_suites, const unsigned char **alpn_protocols,
    const unsigned char *alpn_protocols_lengths, uint16_t num_alpn_protocols,
    tsi_ssl_handshaker_factory **factory);

/* Creates a handshaker.
  - self is the factory from which the handshaker will be created.
  - server_name_indication indicates the name of the server the client is
    trying to connect to which will be relayed to the server using the SNI
    extension.
    This parameter must be NULL for a server handshaker factory.
  - handhshaker is the address of the handshaker pointer to be created.

  - This method returns TSI_OK on success or TSI_INVALID_PARAMETER in the case
    where a parameter is invalid.  */
tsi_result tsi_ssl_handshaker_factory_create_handshaker(
    tsi_ssl_handshaker_factory *self, const char *server_name_indication,
    tsi_handshaker **handshaker);

/* Destroys the handshaker factory. WARNING: it is unsafe to destroy a factory
   while handshakers created with this factory are still in use.  */
void tsi_ssl_handshaker_factory_destroy(tsi_ssl_handshaker_factory *self);

/* Util that checks that an ssl peer matches a specific name.
   Still TODO(jboeuf):
   - handle mixed case.
   - handle %encoded chars.
   - handle public suffix wildchar more strictly (e.g. *.co.uk)
   - handle IP addresses in SAN. */
int tsi_ssl_peer_matches_name(const tsi_peer *peer, const char *name);

#ifdef __cplusplus
}
#endif

#endif /* GRPC_INTERNAL_CORE_TSI_SSL_TRANSPORT_SECURITY_H */