mongocrypt.h

/*
 * Copyright 2019-present MongoDB, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#ifndef MONGOCRYPT_H
#define MONGOCRYPT_H

/** @file mongocrypt.h The top-level handle to libmongocrypt. */

/**
 * @mainpage libmongocrypt
 * See all public API documentation in: @ref mongocrypt.h
 */

#include "mongocrypt-compat.h"
#include "mongocrypt-export.h"

/* clang-format off */
#ifndef __has_include
   #include "mongocrypt-config.h"
#else
   #if __has_include("mongocrypt-config.h")
      #include "mongocrypt-config.h"
   #else
      #error No "mongocrypt-config.h" header is available. That file must \
             be generated in order to use libmongocrypt.
   #endif
#endif
/* clang-format on */

/**
 * Returns the version string for libmongocrypt.
 *
 * @param[out] len  An optional length of the returned string. May be NULL.
 * @returns a NULL terminated version string for libmongocrypt.
 */
MONGOCRYPT_EXPORT
const char *mongocrypt_version(uint32_t *len);

/**
 * Returns true if libmongocrypt was built with native crypto support.
 *
 * If libmongocrypt was not built with native crypto support, setting crypto
 * hooks is required.
 *
 * @returns True if libmongocrypt was built with native crypto support.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_is_crypto_available(void);

/**
 * A non-owning view of a byte buffer.
 *
 * When constructing a mongocrypt_binary_t it is the responsibility of the
 * caller to maintain the lifetime of the viewed data. However, all public
 * functions that take a mongocrypt_binary_t as an argument will make a copy of
 * the viewed data. For example, the following is valid:
 *
 * @code{.c}
 * mongocrypt_binary_t bin = mongocrypt_binary_new_from_data(mydata, mylen);
 * assert (mongocrypt_setopt_kms_provider_local (crypt), bin);
 * // The viewed data of bin has been copied. Ok to free the view and the data.
 * mongocrypt_binary_destroy (bin);
 * my_free_fn (mydata);
 * @endcode
 *
 * Functions with a mongocrypt_binary_t* out guarantee the lifetime of the
 * viewed data to live as long as the parent object. For example, @ref
 * mongocrypt_ctx_mongo_op guarantees that the viewed data of
 * mongocrypt_binary_t is valid until the parent ctx is destroyed with @ref
 * mongocrypt_ctx_destroy.
 *
 * The `mongocrypt_binary_t` struct definition is public.
 * Consumers may rely on the struct layout.
 */
typedef struct _mongocrypt_binary_t {
    void *data;
    uint32_t len;
} mongocrypt_binary_t;

/**
 * Create a new non-owning view of a buffer (data + length).
 *
 * Use this to create a mongocrypt_binary_t used for output parameters.
 *
 * @returns A new mongocrypt_binary_t.
 */
MONGOCRYPT_EXPORT
mongocrypt_binary_t *mongocrypt_binary_new(void);

/**
 * Create a new non-owning view of a buffer (data + length).
 *
 * @param[in] data A pointer to an array of bytes. This data is not copied. @p
 * data must outlive the binary object.
 * @param[in] len The length of the @p data byte array.
 *
 * @returns A new @ref mongocrypt_binary_t.
 */
MONGOCRYPT_EXPORT
mongocrypt_binary_t *mongocrypt_binary_new_from_data(uint8_t *data, uint32_t len);

/**
 * Get a pointer to the viewed data.
 *
 * @param[in] binary The @ref mongocrypt_binary_t.
 *
 * @returns A pointer to the viewed data.
 */
MONGOCRYPT_EXPORT
uint8_t *mongocrypt_binary_data(const mongocrypt_binary_t *binary);

/**
 * Get the length of the viewed data.
 *
 * @param[in] binary The @ref mongocrypt_binary_t.
 *
 * @returns The length of the viewed data.
 */
MONGOCRYPT_EXPORT
uint32_t mongocrypt_binary_len(const mongocrypt_binary_t *binary);

/**
 * Free the @ref mongocrypt_binary_t.
 *
 * This does not free the viewed data.
 *
 * @param[in] binary The mongocrypt_binary_t destroy.
 */
MONGOCRYPT_EXPORT
void mongocrypt_binary_destroy(mongocrypt_binary_t *binary);

/**
 * Indicates success or contains error information.
 *
 * Functions like @ref mongocrypt_ctx_encrypt_init follow a pattern to expose a
 * status. A boolean is returned. True indicates success, and false indicates
 * failure. On failure a status on the handle is set, and is accessible with a
 * corresponding (handle)_status function. E.g. @ref mongocrypt_ctx_status.
 */
typedef struct _mongocrypt_status_t mongocrypt_status_t;

/**
 * Indicates the type of error.
 */
typedef enum {
    MONGOCRYPT_STATUS_OK = 0,
    MONGOCRYPT_STATUS_ERROR_CLIENT = 1,
    MONGOCRYPT_STATUS_ERROR_KMS = 2,
    MONGOCRYPT_STATUS_ERROR_CRYPT_SHARED = 3,
} mongocrypt_status_type_t;

/**
 * Create a new status object.
 *
 * Use a new status object to retrieve the status from a handle by passing
 * this as an out-parameter to functions like @ref mongocrypt_ctx_status.
 * When done, destroy it with @ref mongocrypt_status_destroy.
 *
 * @returns A new status object.
 */
MONGOCRYPT_EXPORT
mongocrypt_status_t *mongocrypt_status_new(void);

/**
 * Set a status object with message, type, and code.
 *
 * Use this to set the @ref mongocrypt_status_t given in the crypto hooks.
 *
 * @param[in] type The status type.
 * @param[in] code The status code.
 * @param[in] message The message.
 * @param[in] message_len Due to historical behavior, pass 1 + the string length
 * of @p message (which differs from other functions accepting string
 * arguments).
 * Alternatively, if message is NULL terminated this may be -1 to tell
 * mongocrypt
 * to determine the string's length with strlen.
 *
 */
MONGOCRYPT_EXPORT
void mongocrypt_status_set(mongocrypt_status_t *status,
                           mongocrypt_status_type_t type,
                           uint32_t code,
                           const char *message,
                           int32_t message_len);

/**
 * Indicates success or the type of error.
 *
 * @param[in] status The status object.
 *
 * @returns A @ref mongocrypt_status_type_t.
 */
MONGOCRYPT_EXPORT
mongocrypt_status_type_t mongocrypt_status_type(mongocrypt_status_t *status);

/**
 * Get an error code or 0.
 *
 * @param[in] status The status object.
 *
 * @returns An error code.
 */
MONGOCRYPT_EXPORT
uint32_t mongocrypt_status_code(mongocrypt_status_t *status);

/**
 * Get the error message associated with a status or NULL.
 *
 * @param[in] status The status object.
 * @param[out] len An optional length of the returned string (excluding the
 * trailing NULL byte). May be NULL.
 *
 * @returns A NULL terminated error message or NULL.
 */
MONGOCRYPT_EXPORT
const char *mongocrypt_status_message(mongocrypt_status_t *status, uint32_t *len);

/**
 * Returns true if the status indicates success.
 *
 * @param[in] status The status to check.
 *
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_status_ok(mongocrypt_status_t *status);

/**
 * Free the memory for a status object.
 *
 * @param[in] status The status to destroy.
 */
MONGOCRYPT_EXPORT
void mongocrypt_status_destroy(mongocrypt_status_t *status);

/**
 * Indicates the type of log message.
 */
typedef enum {
    MONGOCRYPT_LOG_LEVEL_FATAL = 0,
    MONGOCRYPT_LOG_LEVEL_ERROR = 1,
    MONGOCRYPT_LOG_LEVEL_WARNING = 2,
    MONGOCRYPT_LOG_LEVEL_INFO = 3,
    MONGOCRYPT_LOG_LEVEL_TRACE = 4
} mongocrypt_log_level_t;

/**
 * A log callback function. Set a custom log callback with @ref
 * mongocrypt_setopt_log_handler.
 *
 * @param[in] message A NULL terminated message.
 * @param[in] message_len The length of message.
 * @param[in] ctx A context provided by the caller of @ref
 * mongocrypt_setopt_log_handler.
 */
typedef void (*mongocrypt_log_fn_t)(mongocrypt_log_level_t level, const char *message, uint32_t message_len, void *ctx);

/**
 * The top-level handle to libmongocrypt.
 *
 * Create a mongocrypt_t handle to perform operations within libmongocrypt:
 * encryption, decryption, registering log callbacks, etc.
 *
 * Functions on a mongocrypt_t are thread safe, though functions on derived
 * handles (e.g. mongocrypt_ctx_t) are not and must be owned by a single
 * thread. See each handle's documentation for thread-safety considerations.
 *
 * Multiple mongocrypt_t handles may be created.
 */
typedef struct _mongocrypt_t mongocrypt_t;

/**
 * Allocate a new @ref mongocrypt_t object.
 *
 * Set options using mongocrypt_setopt_* functions, then initialize with @ref
 * mongocrypt_init. When done with the @ref mongocrypt_t, free with @ref
 * mongocrypt_destroy.
 *
 * @returns A new @ref mongocrypt_t object.
 */
MONGOCRYPT_EXPORT
mongocrypt_t *mongocrypt_new(void);

/**
 * Set a handler on the @ref mongocrypt_t object to get called on every log
 * message.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] log_fn The log callback.
 * @param[in] log_ctx A context passed as an argument to the log callback every
 * invocation.
 * @pre @ref mongocrypt_init has not been called on @p crypt.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_log_handler(mongocrypt_t *crypt, mongocrypt_log_fn_t log_fn, void *log_ctx);

/**
 * Enable or disable KMS retry behavior.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] enable A boolean indicating whether to retry operations.
 * @pre @ref mongocrypt_init has not been called on @p crypt.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_retry_kms(mongocrypt_t *crypt, bool enable);

/**
 * Enable support for multiple collection schemas. Required to support $lookup.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @pre @ref mongocrypt_init has not been called on @p crypt.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_enable_multiple_collinfo(mongocrypt_t *crypt);

/**
 * Configure an AWS KMS provider on the @ref mongocrypt_t object.
 *
 * This has been superseded by the more flexible:
 * @ref mongocrypt_setopt_kms_providers
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] aws_access_key_id The AWS access key ID used to generate KMS
 * messages.
 * @param[in] aws_access_key_id_len The string length (in bytes) of @p
 * aws_access_key_id. Pass -1 to determine the string length with strlen (must
 * be NULL terminated).
 * @param[in] aws_secret_access_key The AWS secret access key used to generate
 * KMS messages.
 * @param[in] aws_secret_access_key_len The string length (in bytes) of @p
 * aws_secret_access_key. Pass -1 to determine the string length with strlen
 * (must be NULL terminated).
 * @pre @ref mongocrypt_init has not been called on @p crypt.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_kms_provider_aws(mongocrypt_t *crypt,
                                        const char *aws_access_key_id,
                                        int32_t aws_access_key_id_len,
                                        const char *aws_secret_access_key,
                                        int32_t aws_secret_access_key_len);

/**
 * Configure a local KMS provider on the @ref mongocrypt_t object.
 *
 * This has been superseded by the more flexible:
 * @ref mongocrypt_setopt_kms_providers
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] key A 96 byte master key used to encrypt and decrypt key vault
 * keys. The viewed data is copied. It is valid to destroy @p key with @ref
 * mongocrypt_binary_destroy immediately after.
 * @pre @ref mongocrypt_init has not been called on @p crypt.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_kms_provider_local(mongocrypt_t *crypt, mongocrypt_binary_t *key);

/**
 * Configure KMS providers with a BSON document.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] kms_providers A BSON document mapping the KMS provider names
 * to credentials. Set a KMS provider value to an empty document to supply
 * credentials on-demand with @ref mongocrypt_ctx_provide_kms_providers.
 * @pre @ref mongocrypt_init has not been called on @p crypt.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_kms_providers(mongocrypt_t *crypt, mongocrypt_binary_t *kms_providers);

/**
 * Set a local schema map for encryption.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] schema_map A BSON document representing the schema map supplied by
 * the user. The keys are collection namespaces and values are JSON schemas. The
 * viewed data copied. It is valid to destroy @p schema_map with @ref
 * mongocrypt_binary_destroy immediately after.
 * @pre @p crypt has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_schema_map(mongocrypt_t *crypt, mongocrypt_binary_t *schema_map);

/**
 * Set a local EncryptedFieldConfigMap for encryption.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] efc_map A BSON document representing the EncryptedFieldConfigMap
 * supplied by the user. The keys are collection namespaces and values are
 * EncryptedFieldConfigMap documents. The viewed data copied. It is valid to
 * destroy @p efc_map with @ref mongocrypt_binary_destroy immediately after.
 * @pre @p crypt has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_encrypted_field_config_map(mongocrypt_t *crypt, mongocrypt_binary_t *efc_map);

/**
 * @brief Append an additional search directory to the search path for loading
 * the crypt_shared dynamic library.
 *
 * @param[in] crypt The @ref mongocrypt_t object to update
 * @param[in] path A null-terminated sequence of bytes for the search path. On
 * some filesystems, this may be arbitrary bytes. On other filesystems, this may
 * be required to be a valid UTF-8 code unit sequence. If the leading element of
 * the path is the literal string "$ORIGIN", that substring will be replaced
 * with the directory path containing the executable libmongocrypt module. If
 * the path string is literal "$SYSTEM", then libmongocrypt will defer to the
 * system's library resolution mechanism to find the crypt_shared library.
 *
 * @note If no crypt_shared dynamic library is found in any of the directories
 * specified by the search paths loaded here, @ref mongocrypt_init() will still
 * succeed and continue to operate without crypt_shared.
 *
 * @note The search paths are searched in the order that they are appended. This
 * allows one to provide a precedence in how the library will be discovered. For
 * example, appending known directories before appending "$SYSTEM" will allow
 * one to supersede the system's installed library, but still fall-back to it if
 * the library wasn't found otherwise. If one does not ever append "$SYSTEM",
 * then the system's library-search mechanism will never be consulted.
 *
 * @note If an absolute path to the library is specified using
 * @ref mongocrypt_setopt_set_crypt_shared_lib_path_override, then paths
 * appended here will have no effect.
 */
MONGOCRYPT_EXPORT
void mongocrypt_setopt_append_crypt_shared_lib_search_path(mongocrypt_t *crypt, const char *path);

/**
 * @brief Set a single override path for loading the crypt_shared dynamic
 * library.
 *
 * @param[in] crypt The @ref mongocrypt_t object to update
 * @param[in] path A null-terminated sequence of bytes for a path to the
 * crypt_shared dynamic library. On some filesystems, this may be arbitrary
 * bytes. On other filesystems, this may be required to be a valid UTF-8 code
 * unit sequence. If the leading element of the path is the literal string
 * `$ORIGIN`, that substring will be replaced with the directory path containing
 * the executable libmongocrypt module.
 *
 * @note This function will do no IO nor path validation. All validation will
 * occur during the call to @ref mongocrypt_init.
 *
 * @note If a crypt_shared library path override is specified here, then no
 * paths given to @ref mongocrypt_setopt_append_crypt_shared_lib_search_path
 * will be consulted when opening the crypt_shared library.
 *
 * @note If a path is provided via this API and @ref mongocrypt_init fails to
 * initialize a valid crypt_shared library instance for the path specified, then
 * the initialization of mongocrypt_t will fail with an error.
 */
MONGOCRYPT_EXPORT
void mongocrypt_setopt_set_crypt_shared_lib_path_override(mongocrypt_t *crypt, const char *path);

/**
 * @brief Opt-into handling the MONGOCRYPT_CTX_NEED_KMS_CREDENTIALS state.
 *
 * If set, before entering the MONGOCRYPT_CTX_NEED_KMS state,
 * contexts may enter the MONGOCRYPT_CTX_NEED_KMS_CREDENTIALS state
 * and then wait for credentials to be supplied through
 * @ref mongocrypt_ctx_provide_kms_providers.
 *
 * A context will only enter MONGOCRYPT_CTX_NEED_KMS_CREDENTIALS
 * if an empty document was set for a KMS provider in @ref
 * mongocrypt_setopt_kms_providers.
 *
 * @param[in] crypt The @ref mongocrypt_t object to update
 */
MONGOCRYPT_EXPORT
void mongocrypt_setopt_use_need_kms_credentials_state(mongocrypt_t *crypt);

/**
 * @brief Opt-into handling the MONGOCRYPT_CTX_NEED_MONGO_COLLINFO_WITH_DB state.
 *
 * A context enters the MONGOCRYPT_CTX_NEED_MONGO_COLLINFO_WITH_DB state when
 * processing a `bulkWrite` command. The target database of the `bulkWrite` may differ from the command database
 * ("admin").
 *
 * @param[in] crypt The @ref mongocrypt_t object to update
 */
MONGOCRYPT_EXPORT
void mongocrypt_setopt_use_need_mongo_collinfo_with_db_state(mongocrypt_t *crypt);

/**
 * Initialize new @ref mongocrypt_t object.
 *
 * Set options before using @ref mongocrypt_setopt_kms_provider_local, @ref
 * mongocrypt_setopt_kms_provider_aws, or @ref mongocrypt_setopt_log_handler.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 *
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status Failure may occur if previously
 * set
 * options are invalid.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_init(mongocrypt_t *crypt);

/**
 * Get the status associated with a @ref mongocrypt_t object.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[out] status Receives the status.
 *
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_status(mongocrypt_t *crypt, mongocrypt_status_t *status);

/**
 * Destroy the @ref mongocrypt_t object.
 *
 * @param[in] crypt The @ref mongocrypt_t object to destroy.
 */
MONGOCRYPT_EXPORT
void mongocrypt_destroy(mongocrypt_t *crypt);

/**
 * Obtain a nul-terminated version string of the loaded crypt_shared dynamic
 * library, if available.
 *
 * If no crypt_shared was successfully loaded, this function returns NULL.
 *
 * @param[in] crypt The mongocrypt_t object after a successful call to
 * mongocrypt_init.
 * @param[out] len An optional output parameter to which the length of the
 * returned string is written. If provided and no crypt_shared library was
 * loaded, zero is written to *len.
 *
 * @return A nul-terminated string of the dynamically loaded crypt_shared
 * library.
 *
 * @note For a numeric value that can be compared against, use
 * @ref mongocrypt_crypt_shared_lib_version.
 */
MONGOCRYPT_EXPORT
const char *mongocrypt_crypt_shared_lib_version_string(const mongocrypt_t *crypt, uint32_t *len);

/**
 * @brief Obtain a 64-bit constant encoding the version of the loaded
 * crypt_shared library, if available.
 *
 * @param[in] crypt The mongocrypt_t object after a successful call to
 * mongocrypt_init.
 *
 * @return A 64-bit encoded version number, with the version encoded as four
 * sixteen-bit integers, or zero if no crypt_shared library was loaded.
 *
 * The version is encoded as four 16-bit numbers, from high to low:
 *
 * - Major version
 * - Minor version
 * - Revision
 * - Reserved
 *
 * For example, version 6.2.1 would be encoded as: 0x0006'0002'0001'0000
 */
MONGOCRYPT_EXPORT
uint64_t mongocrypt_crypt_shared_lib_version(const mongocrypt_t *crypt);

/**
 * Manages the state machine for encryption or decryption.
 */
typedef struct _mongocrypt_ctx_t mongocrypt_ctx_t;

/**
 * Create a new uninitialized @ref mongocrypt_ctx_t.
 *
 * Initialize the context with functions like @ref mongocrypt_ctx_encrypt_init.
 * When done, destroy it with @ref mongocrypt_ctx_destroy.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @returns A new context.
 */
MONGOCRYPT_EXPORT
mongocrypt_ctx_t *mongocrypt_ctx_new(mongocrypt_t *crypt);

/**
 * Get the status associated with a @ref mongocrypt_ctx_t object.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[out] status Receives the status.
 *
 * @returns True if the output is an ok status, false if it is an error
 * status.
 *
 * @see mongocrypt_status_ok
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_status(mongocrypt_ctx_t *ctx, mongocrypt_status_t *status);

/**
 * Set the key id to use for explicit encryption.
 *
 * It is an error to set both this and the key alt name.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] key_id The binary corresponding to the _id (a UUID) of the data
 * key to use from the key vault collection. Note, the UUID must be encoded with
 * RFC-4122 byte order. The viewed data is copied. It is valid to destroy
 * @p key_id with @ref mongocrypt_binary_destroy immediately after.
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_key_id(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *key_id);

/**
 * Set the keyAltName to use for explicit encryption or
 * data key creation.
 *
 * Pass the binary encoding a BSON document like the following:
 *
 *   { "keyAltName" : (BSON UTF8 value) }
 *
 * For explicit encryption, it is an error to set both the keyAltName
 * and the key id.
 *
 * For creating data keys, call this function repeatedly to set
 * multiple keyAltNames.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] key_alt_name The name to use. The viewed data is copied. It is
 * valid to destroy @p key_alt_name with @ref mongocrypt_binary_destroy
 * immediately after.
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_key_alt_name(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *key_alt_name);

/**
 * Set the keyMaterial to use for encrypting data.
 *
 * Pass the binary encoding of a BSON document like the following:
 *
 *   { "keyMaterial" : (BSON BINARY value) }
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] key_material The data encryption key to use. The viewed data is
 * copied. It is valid to destroy @p key_material with @ref
 * mongocrypt_binary_destroy immediately after.
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_key_material(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *key_material);

/**
 * Set the algorithm used for encryption to either
 * deterministic or random encryption. This value
 * should only be set when using explicit encryption.
 *
 * If -1 is passed in for "len", then "algorithm" is
 * assumed to be a null-terminated string.
 *
 * Valid values for algorithm are:
 *   "AEAD_AES_256_CBC_HMAC_SHA_512-Deterministic"
 *   "AEAD_AES_256_CBC_HMAC_SHA_512-Random"
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] algorithm A string specifying the algorithm to
 * use for encryption.
 * @param[in] len The length of the algorithm string.
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_algorithm(mongocrypt_ctx_t *ctx, const char *algorithm, int len);

/// String constant for setopt_algorithm "Deterministic" encryption
#define MONGOCRYPT_ALGORITHM_DETERMINISTIC_STR "AEAD_AES_256_CBC_HMAC_SHA_512-Deterministic"
/// String constant for setopt_algorithm "Random" encryption
#define MONGOCRYPT_ALGORITHM_RANDOM_STR "AEAD_AES_256_CBC_HMAC_SHA_512-Random"
/// String constant for setopt_algorithm "Indexed" explicit encryption
#define MONGOCRYPT_ALGORITHM_INDEXED_STR "Indexed"
/// String constant for setopt_algorithm "Unindexed" explicit encryption
#define MONGOCRYPT_ALGORITHM_UNINDEXED_STR "Unindexed"
// DEPRECATED: support "RangePreview" has been removed in favor of "range".
#define MONGOCRYPT_ALGORITHM_RANGEPREVIEW_DEPRECATED_STR "RangePreview"
#define MONGOCRYPT_ALGORITHM_RANGE_STR "Range"

/**
 * Identify the AWS KMS master key to use for creating a data key.
 *
 * This has been superseded by the more flexible:
 * @ref mongocrypt_ctx_setopt_key_encryption_key
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] region The AWS region.
 * @param[in] region_len The string length of @p region. Pass -1 to determine
 * the string length with strlen (must be NULL terminated).
 * @param[in] cmk The Amazon Resource Name (ARN) of the customer master key
 * (CMK).
 * @param[in] cmk_len The string length of @p cmk_len. Pass -1 to determine the
 * string length with strlen (must be NULL terminated).
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_masterkey_aws(mongocrypt_ctx_t *ctx,
                                         const char *region,
                                         int32_t region_len,
                                         const char *cmk,
                                         int32_t cmk_len);

/**
 * Identify a custom AWS endpoint when creating a data key.
 * This is used internally to construct the correct HTTP request
 * (with the Host header set to this endpoint). This endpoint
 * is persisted in the new data key, and will be returned via
 * @ref mongocrypt_kms_ctx_endpoint.
 *
 * This has been superseded by the more flexible:
 * @ref mongocrypt_ctx_setopt_key_encryption_key
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] endpoint The endpoint.
 * @param[in] endpoint_len The string length of @p endpoint. Pass -1 to
 * determine the string length with strlen (must be NULL terminated).
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_masterkey_aws_endpoint(mongocrypt_ctx_t *ctx, const char *endpoint, int32_t endpoint_len);

/**
 * Set the master key to "local" for creating a data key.
 * This has been superseded by the more flexible:
 * @ref mongocrypt_ctx_setopt_key_encryption_key
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_masterkey_local(mongocrypt_ctx_t *ctx);

/**
 * Set key encryption key document for creating a data key or for rewrapping
 * datakeys.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] bin BSON representing the key encryption key document with
 * an additional "provider" field. The following forms are accepted:
 *
 * AWS
 * {
 *    provider: "aws",
 *    region: <string>,
 *    key: <string>,
 *    endpoint: <optional string>
 * }
 *
 * Azure
 * {
 *    provider: "azure",
 *    keyVaultEndpoint: <string>,
 *    keyName: <string>,
 *    keyVersion: <optional string>
 * }
 *
 * GCP
 * {
 *    provider: "gcp",
 *    projectId: <string>,
 *    location: <string>,
 *    keyRing: <string>,
 *    keyName: <string>,
 *    keyVersion: <optional string>,
 *    endpoint: <optional string>
 * }
 *
 * Local
 * {
 *    provider: "local"
 * }
 *
 * KMIP
 * {
 *    provider: "kmip",
 *    keyId: <optional string>
 *    endpoint: <string>
 * }
 *
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_key_encryption_key(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *bin);

/**
 * Initialize a context to create a data key.
 *
 * Associated options:
 * - @ref mongocrypt_ctx_setopt_masterkey_aws
 * - @ref mongocrypt_ctx_setopt_masterkey_aws_endpoint
 * - @ref mongocrypt_ctx_setopt_masterkey_local
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 * @pre A master key option has been set, and an associated KMS provider
 * has been set on the parent @ref mongocrypt_t.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_datakey_init(mongocrypt_ctx_t *ctx);

/**
 * Initialize a context for encryption.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] db The database name.
 * @param[in] db_len The byte length of @p db. Pass -1 to determine the string
 * length with strlen (must
 * be NULL terminated).
 * @param[in] cmd The BSON command to be encrypted. The viewed data is copied.
 * It is valid to destroy @p cmd with @ref mongocrypt_binary_destroy immediately
 * after.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_encrypt_init(mongocrypt_ctx_t *ctx, const char *db, int32_t db_len, mongocrypt_binary_t *cmd);

/**
 * Explicit helper method to encrypt a single BSON object. Contexts
 * created for explicit encryption will not go through mongocryptd.
 *
 * To specify a key_id, algorithm, or iv to use, please use the
 * corresponding mongocrypt_setopt methods before calling this.
 *
 * This method expects the passed-in BSON to be of the form:
 * { "v" : BSON value to encrypt }
 *
 * The value of "v" is expected to be the BSON value passed to a driver
 * ClientEncryption.encrypt helper.
 *
 * Associated options for FLE 1:
 * - @ref mongocrypt_ctx_setopt_key_id
 * - @ref mongocrypt_ctx_setopt_key_alt_name
 * - @ref mongocrypt_ctx_setopt_algorithm
 *
 * Associated options for Queryable Encryption:
 * - @ref mongocrypt_ctx_setopt_key_id
 * - @ref mongocrypt_ctx_setopt_index_key_id
 * - @ref mongocrypt_ctx_setopt_contention_factor
 * - @ref mongocrypt_ctx_setopt_query_type
 * - @ref mongocrypt_ctx_setopt_algorithm_range
 *
 * An error is returned if FLE 1 and Queryable Encryption incompatible options
 * are set.
 *
 * @param[in] ctx A @ref mongocrypt_ctx_t.
 * @param[in] msg A @ref mongocrypt_binary_t the plaintext BSON value. The
 * viewed data is copied. It is valid to destroy @p msg with @ref
 * mongocrypt_binary_destroy immediately after.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_explicit_encrypt_init(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *msg);

/**
 * Explicit helper method to encrypt a Match Expression or Aggregate Expression.
 * Contexts created for explicit encryption will not go through mongocryptd.
 * Requires query_type to be "range".
 *
 * This method expects the passed-in BSON to be of the form:
 * { "v" : FLE2RangeFindDriverSpec }
 *
 * FLE2RangeFindDriverSpec is a BSON document with one of these forms:
 *
 * 1. A Match Expression of this form:
 *    {$and: [{<field>: {<op>: <value1>, {<field>: {<op>: <value2> }}]}
 * 2. An Aggregate Expression of this form:
 *    {$and: [{<op>: [<fieldpath>, <value1>]}, {<op>: [<fieldpath>, <value2>]}]
 *
 * <op> may be $lt, $lte, $gt, or $gte.
 *
 * The value of "v" is expected to be the BSON value passed to a driver
 * ClientEncryption.encryptExpression helper.
 *
 * Associated options for FLE 1:
 * - @ref mongocrypt_ctx_setopt_key_id
 * - @ref mongocrypt_ctx_setopt_key_alt_name
 * - @ref mongocrypt_ctx_setopt_algorithm
 *
 * Associated options for Queryable Encryption:
 * - @ref mongocrypt_ctx_setopt_key_id
 * - @ref mongocrypt_ctx_setopt_index_key_id
 * - @ref mongocrypt_ctx_setopt_contention_factor
 * - @ref mongocrypt_ctx_setopt_query_type
 * - @ref mongocrypt_ctx_setopt_algorithm_range
 *
 * An error is returned if FLE 1 and Queryable Encryption incompatible options
 * are set.
 *
 * @param[in] ctx A @ref mongocrypt_ctx_t.
 * @param[in] msg A @ref mongocrypt_binary_t the plaintext BSON value. The
 * viewed data is copied. It is valid to destroy @p msg with @ref
 * mongocrypt_binary_destroy immediately after.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_explicit_encrypt_expression_init(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *msg);

/**
 * Initialize a context for decryption.
 *
 * This method expects the passed-in BSON to be of the form:
 * { "v" : BSON value to encrypt }
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] doc The document to be decrypted. The viewed data is copied. It is
 * valid to destroy @p doc with @ref mongocrypt_binary_destroy immediately
 * after.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_decrypt_init(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *doc);

/**
 * Explicit helper method to decrypt a single BSON object.
 *
 * Pass the binary encoding of a BSON document containing the BSON value to
 * encrypt like the following:
 *
 *   { "v" : (BSON BINARY value of subtype 6) }
 *
 * @param[in] ctx A @ref mongocrypt_ctx_t.
 * @param[in] msg A @ref mongocrypt_binary_t the encrypted BSON. The viewed data
 * is copied. It is valid to destroy @p msg with @ref mongocrypt_binary_destroy
 * immediately after.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_explicit_decrypt_init(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *msg);

/**
 * @brief Initialize a context to rewrap datakeys.
 *
 * Associated options:
 * - @ref mongocrypt_ctx_setopt_key_encryption_key
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] filter The filter to use for the find command on the key vault
 * collection to retrieve datakeys to rewrap.
 * @return A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_rewrap_many_datakey_init(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *filter);

/**
 * Indicates the state of the @ref mongocrypt_ctx_t. Each state requires
 * different handling. See [the integration
 * guide](https://github.com/mongodb/libmongocrypt/blob/master/integrating.md#state-machine)
 * for information on what to do for each state.
 */
typedef enum {
    MONGOCRYPT_CTX_ERROR = 0,
    MONGOCRYPT_CTX_NEED_MONGO_COLLINFO = 1,         /* run on main MongoClient */
    MONGOCRYPT_CTX_NEED_MONGO_COLLINFO_WITH_DB = 8, /* run on main MongoClient */
    MONGOCRYPT_CTX_NEED_MONGO_MARKINGS = 2,         /* run on mongocryptd. */
    MONGOCRYPT_CTX_NEED_MONGO_KEYS = 3,             /* run on key vault */
    MONGOCRYPT_CTX_NEED_KMS = 4,
    MONGOCRYPT_CTX_NEED_KMS_CREDENTIALS = 7, /* fetch/renew KMS credentials */
    MONGOCRYPT_CTX_READY = 5,                /* ready for encryption/decryption */
    MONGOCRYPT_CTX_DONE = 6,
} mongocrypt_ctx_state_t;

/**
 * Get the current state of a context.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @returns A @ref mongocrypt_ctx_state_t.
 */
MONGOCRYPT_EXPORT
mongocrypt_ctx_state_t mongocrypt_ctx_state(mongocrypt_ctx_t *ctx);

/**
 * Get BSON necessary to run the mongo operation when mongocrypt_ctx_t
 * is in MONGOCRYPT_CTX_NEED_MONGO_* states.
 *
 * @p op_bson is a BSON document to be used for the operation.
 * - For MONGOCRYPT_CTX_NEED_MONGO_COLLINFO(_WITH_DB) it is a listCollections filter.
 * - For MONGOCRYPT_CTX_NEED_MONGO_KEYS it is a find filter.
 * - For MONGOCRYPT_CTX_NEED_MONGO_MARKINGS it is a command to send to
 * mongocryptd.
 *
 * The lifetime of @p op_bson is tied to the lifetime of @p ctx. It is valid
 * until @ref mongocrypt_ctx_destroy is called.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[out] op_bson A BSON document for the MongoDB operation. The data
 * viewed by @p op_bson is guaranteed to be valid until @p ctx is destroyed with
 * @ref mongocrypt_ctx_destroy.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_mongo_op(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *op_bson);

/**
 * Get the database to run the mongo operation.
 *
 * Only applies when mongocrypt_ctx_t is in the state:
 * MONGOCRYPT_CTX_NEED_MONGO_COLLINFO_WITH_DB.
 *
 * The lifetime of the returned string is tied to the lifetime of @p ctx. It is
 * valid until @ref mongocrypt_ctx_destroy is called.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @returns A string or NULL. If NULL, an error status is set. Retrieve it with
 * @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
const char *mongocrypt_ctx_mongo_db(mongocrypt_ctx_t *ctx);

/**
 * Feed a BSON reply or result when mongocrypt_ctx_t is in
 * MONGOCRYPT_CTX_NEED_MONGO_* states. This may be called multiple times
 * depending on the operation.
 *
 * reply is a BSON document result being fed back for this operation.
 * - For MONGOCRYPT_CTX_NEED_MONGO_COLLINFO(_WITH_DB) it is a doc from a listCollections
 * cursor. (Note, if listCollections returned no result, do not call this
 * function.)
 * - For MONGOCRYPT_CTX_NEED_MONGO_KEYS it is a doc from a find cursor.
 *   (Note, if find returned no results, do not call this function. reply must
 * not
 *   be NULL.)
 * - For MONGOCRYPT_CTX_NEED_MONGO_MARKINGS it is a reply from mongocryptd.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] reply A BSON document for the MongoDB operation. The viewed data
 * is copied. It is valid to destroy @p reply with @ref
 * mongocrypt_binary_destroy immediately after.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_mongo_feed(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *reply);

/**
 * Call when done feeding the reply (or replies) back to the context.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_mongo_done(mongocrypt_ctx_t *ctx);

/**
 * Manages a single KMS HTTP request/response.
 */
typedef struct _mongocrypt_kms_ctx_t mongocrypt_kms_ctx_t;

/**
 * Get the next KMS handle.
 *
 * Multiple KMS handles may be retrieved at once. Drivers may do this to fan
 * out multiple concurrent KMS HTTP requests. Feeding multiple KMS requests
 * is thread-safe.
 *
 * If KMS handles are being handled synchronously, the driver can reuse the same
 * TLS socket to send HTTP requests and receive responses.
 *
 * The returned KMS handle does not outlive `ctx`.
 *
 * @param[in] ctx A @ref mongocrypt_ctx_t.
 * @returns a new @ref mongocrypt_kms_ctx_t or NULL.
 */
MONGOCRYPT_EXPORT
mongocrypt_kms_ctx_t *mongocrypt_ctx_next_kms_ctx(mongocrypt_ctx_t *ctx);

/**
 * Get the HTTP request message for a KMS handle.
 *
 * The lifetime of @p msg is tied to the lifetime of @p kms. It is valid
 * until @ref mongocrypt_ctx_kms_done is called.
 *
 * @param[in] kms A @ref mongocrypt_kms_ctx_t.
 * @param[out] msg The HTTP request to send to KMS. The data viewed by @p msg is
 * guaranteed to be valid until the call of @ref mongocrypt_ctx_kms_done of the
 * parent @ref mongocrypt_ctx_t.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_kms_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_kms_ctx_message(mongocrypt_kms_ctx_t *kms, mongocrypt_binary_t *msg);

/**
 * Get the hostname from which to connect over TLS.
 *
 * The storage for @p endpoint is not owned by the caller, but
 * is valid until calling @ref mongocrypt_ctx_kms_done.
 *
 * @param[in] kms A @ref mongocrypt_kms_ctx_t.
 * @param[out] endpoint The output endpoint as a NULL terminated string.
 * The endpoint consists of a hostname and port separated by a colon.
 * E.g. "example.com:123". A port is always present.
 *
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_kms_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_kms_ctx_endpoint(mongocrypt_kms_ctx_t *kms, const char **endpoint);

/**
 * Indicates how many bytes to feed into @ref mongocrypt_kms_ctx_feed.
 *
 * @param[in] kms The @ref mongocrypt_kms_ctx_t.
 * @returns The number of requested bytes.
 */
MONGOCRYPT_EXPORT
uint32_t mongocrypt_kms_ctx_bytes_needed(mongocrypt_kms_ctx_t *kms);

/**
 * Indicates how long to sleep before sending this request.
 *
 * @param[in] kms The @ref mongocrypt_kms_ctx_t.
 * @returns How long to sleep in microseconds.
 */
MONGOCRYPT_EXPORT
int64_t mongocrypt_kms_ctx_usleep(mongocrypt_kms_ctx_t *kms);

/**
 * Feed bytes from the HTTP response.
 *
 * Feeding more bytes than what has been returned in @ref
 * mongocrypt_kms_ctx_bytes_needed is an error.
 *
 * @param[in] kms The @ref mongocrypt_kms_ctx_t.
 * @param[in] bytes The bytes to feed. The viewed data is copied. It is valid to
 * destroy @p bytes with @ref mongocrypt_binary_destroy immediately after.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_kms_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_kms_ctx_feed(mongocrypt_kms_ctx_t *kms, mongocrypt_binary_t *bytes);

/**
 * Indicate a network-level failure.
 *
 * @param[in] kms The @ref mongocrypt_kms_ctx_t.
 * @return A boolean indicating whether the failed request may be retried.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_kms_ctx_fail(mongocrypt_kms_ctx_t *kms);

/**
 * Get the status associated with a @ref mongocrypt_kms_ctx_t object.
 *
 * @param[in] kms The @ref mongocrypt_kms_ctx_t object.
 * @param[out] status Receives the status.
 *
 * @returns A boolean indicating success. If false, an error status is set.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_kms_ctx_status(mongocrypt_kms_ctx_t *kms, mongocrypt_status_t *status);

/**
 * Get the KMS provider identifier associated with this KMS request.
 *
 * This is used to conditionally configure TLS connections based on the KMS
 * request. It is useful for KMIP, which authenticates with a client
 * certificate.
 *
 * @param[in] kms The @ref mongocrypt_kms_ctx_t object.
 * @param[out] len Receives the length of the returned string. It may be NULL.
 * If it is not NULL, it is set to the length of the returned string without
 * the NULL terminator.
 *
 * @returns One of the NULL terminated static strings: "aws", "azure", "gcp", or
 * "kmip".
 */
MONGOCRYPT_EXPORT
const char *mongocrypt_kms_ctx_get_kms_provider(mongocrypt_kms_ctx_t *kms, uint32_t *len);

/**
 * Call when done handling all KMS contexts.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 *
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_kms_done(mongocrypt_ctx_t *ctx);

/**
 * Call in response to the MONGOCRYPT_CTX_NEED_KMS_CREDENTIALS state
 * to set per-context KMS provider settings. These follow the same format
 * as @ref mongocrypt_setopt_kms_providers. If no keys are present in the
 * BSON input, the KMS provider settings configured for the @ref mongocrypt_t
 * at initialization are used.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] kms_providers_definition A BSON document mapping the KMS provider
 * names to credentials.
 *
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_provide_kms_providers(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *kms_providers_definition);

/**
 * Perform the final encryption or decryption.
 *
 * @param[in] ctx A @ref mongocrypt_ctx_t.
 * @param[out] out The final BSON. The data viewed by @p out is guaranteed
 * to be valid until @p ctx is destroyed with @ref mongocrypt_ctx_destroy.
 * The meaning of this BSON depends on the type of @p ctx.
 *
 * If @p ctx was initialized with @ref mongocrypt_ctx_encrypt_init, then
 * this BSON is the (possibly) encrypted command to send to the server.
 *
 * If @p ctx was initialized with @ref mongocrypt_ctx_decrypt_init, then
 * this BSON is the decrypted result to return to the user.
 *
 * If @p ctx was initialized with @ref mongocrypt_ctx_explicit_encrypt_init,
 * then this BSON has the form { "v": (BSON binary) } where the BSON binary
 * is the resulting encrypted value.
 *
 * If @p ctx was initialized with @ref mongocrypt_ctx_explicit_decrypt_init,
 * then this BSON has the form { "v": (BSON value) } where the BSON value
 * is the resulting decrypted value.
 *
 * If @p ctx was initialized with @ref mongocrypt_ctx_datakey_init, then
 * this BSON is the document containing the new data key to be inserted into
 * the key vault collection.
 *
 * If @p ctx was initialized with @ref mongocrypt_ctx_rewrap_many_datakey_init,
 * then this BSON has the form:
 *   { "v": [{ "_id": ..., "keyMaterial": ..., "masterKey": ... }, ...] }
 * where each BSON document in the array contains the updated fields of a
 * rewrapped datakey to be bulk-updated into the key vault collection.
 * Note: the updateDate field should be updated using the $currentDate operator.
 *
 * @returns a bool indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_finalize(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *out);

/**
 * Destroy and free all memory associated with a @ref mongocrypt_ctx_t.
 *
 * @param[in] ctx A @ref mongocrypt_ctx_t.
 */
MONGOCRYPT_EXPORT
void mongocrypt_ctx_destroy(mongocrypt_ctx_t *ctx);

/**
 * An crypto AES-256-CBC encrypt or decrypt function.
 *
 * Note, @p in is already padded. Encrypt with padding disabled.
 * @param[in] ctx An optional context object that may have been set when hooks
 * were enabled.
 * @param[in] key An encryption key (32 bytes for AES_256).
 * @param[in] iv An initialization vector (16 bytes for AES_256);
 * @param[in] in The input.
 * @param[out] out A preallocated byte array for the output. See @ref
 * mongocrypt_binary_data.
 * @param[out] bytes_written Set this to the number of bytes written to @p out.
 * @param[out] status An optional status to pass error messages. See @ref
 * mongocrypt_status_set.
 * @returns A boolean indicating success. If returning false, set @p status
 * with a message indicating the error using @ref mongocrypt_status_set.
 */
typedef bool (*mongocrypt_crypto_fn)(void *ctx,
                                     mongocrypt_binary_t *key,
                                     mongocrypt_binary_t *iv,
                                     mongocrypt_binary_t *in,
                                     mongocrypt_binary_t *out,
                                     uint32_t *bytes_written,
                                     mongocrypt_status_t *status);

/**
 * A crypto signature or HMAC function.
 *
 * Currently used in callbacks for HMAC SHA-512, HMAC SHA-256, and RSA SHA-256
 * signature.
 *
 * @param[in] ctx An optional context object that may have been set when hooks
 * were enabled.
 * @param[in] key An encryption key (32 bytes for HMAC_SHA512).
 * @param[in] in The input.
 * @param[out] out A preallocated byte array for the output. See @ref
 * mongocrypt_binary_data.
 * @param[out] status An optional status to pass error messages. See @ref
 * mongocrypt_status_set.
 * @returns A boolean indicating success. If returning false, set @p status
 * with a message indicating the error using @ref mongocrypt_status_set.
 */
typedef bool (*mongocrypt_hmac_fn)(void *ctx,
                                   mongocrypt_binary_t *key,
                                   mongocrypt_binary_t *in,
                                   mongocrypt_binary_t *out,
                                   mongocrypt_status_t *status);

/**
 * A crypto hash (SHA-256) function.
 *
 * @param[in] ctx An optional context object that may have been set when hooks
 * were enabled.
 * @param[in] in The input.
 * @param[out] out A preallocated byte array for the output. See @ref
 * mongocrypt_binary_data.
 * @param[out] status An optional status to pass error messages. See @ref
 * mongocrypt_status_set.
 * @returns A boolean indicating success. If returning false, set @p status
 * with a message indicating the error using @ref mongocrypt_status_set.
 */
typedef bool (*mongocrypt_hash_fn)(void *ctx,
                                   mongocrypt_binary_t *in,
                                   mongocrypt_binary_t *out,
                                   mongocrypt_status_t *status);

/**
 * A crypto secure random function.
 *
 * @param[in] ctx An optional context object that may have been set when hooks
 * were enabled.
 * @param[out] out A preallocated byte array for the output. See @ref
 * mongocrypt_binary_data.
 * @param[in] count The number of random bytes requested.
 * @param[out] status An optional status to pass error messages. See @ref
 * mongocrypt_status_set.
 * @returns A boolean indicating success. If returning false, set @p status
 * with a message indicating the error using @ref mongocrypt_status_set.
 */
typedef bool (*mongocrypt_random_fn)(void *ctx, mongocrypt_binary_t *out, uint32_t count, mongocrypt_status_t *status);

MONGOCRYPT_EXPORT
bool mongocrypt_setopt_crypto_hooks(mongocrypt_t *crypt,
                                    mongocrypt_crypto_fn aes_256_cbc_encrypt,
                                    mongocrypt_crypto_fn aes_256_cbc_decrypt,
                                    mongocrypt_random_fn random,
                                    mongocrypt_hmac_fn hmac_sha_512,
                                    mongocrypt_hmac_fn hmac_sha_256,
                                    mongocrypt_hash_fn sha_256,
                                    void *ctx);

/**
 * Set a crypto hook for the AES256-CTR operations.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] aes_256_ctr_encrypt The crypto callback function for encrypt
 * operation.
 * @param[in] aes_256_ctr_decrypt The crypto callback function for decrypt
 * operation.
 * @param[in] ctx Unused.
 * @pre @ref mongocrypt_init has not been called on @p crypt.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_status
 *
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_aes_256_ctr(mongocrypt_t *crypt,
                                   mongocrypt_crypto_fn aes_256_ctr_encrypt,
                                   mongocrypt_crypto_fn aes_256_ctr_decrypt,
                                   void *ctx);

/**
 * Set an AES256-ECB crypto hook for the AES256-CTR operations. If CTR hook was
 * configured using @ref mongocrypt_setopt_aes_256_ctr, ECB hook will be
 * ignored.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] aes_256_ecb_encrypt The crypto callback function for encrypt
 * operation.
 * @param[in] ctx Unused.
 * @pre @ref mongocrypt_init has not been called on @p crypt.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_status
 *
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_aes_256_ecb(mongocrypt_t *crypt, mongocrypt_crypto_fn aes_256_ecb_encrypt, void *ctx);

/**
 * Set a crypto hook for the RSASSA-PKCS1-v1_5 algorithm with a SHA-256 hash.
 *
 * See: https://tools.ietf.org/html/rfc3447#section-8.2
 *
 * Note: this function has the wrong name. It should be:
 * mongocrypt_setopt_crypto_hook_sign_rsassa_pkcs1_v1_5
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 * @param[in] sign_rsaes_pkcs1_v1_5 The crypto callback function.
 * @param[in] sign_ctx A context passed as an argument to the crypto callback
 * every invocation.
 * @pre @ref mongocrypt_init has not been called on @p crypt.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_status
 *
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_crypto_hook_sign_rsaes_pkcs1_v1_5(mongocrypt_t *crypt,
                                                         mongocrypt_hmac_fn sign_rsaes_pkcs1_v1_5,
                                                         void *sign_ctx);

/**
 * @brief Opt-into skipping query analysis.
 *
 * If opted in:
 * - The crypt_shared library will not attempt to be loaded.
 * - A mongocrypt_ctx_t will never enter the MONGOCRYPT_CTX_NEED_MARKINGS state.
 *
 * @param[in] crypt The @ref mongocrypt_t object to update
 */
MONGOCRYPT_EXPORT
void mongocrypt_setopt_bypass_query_analysis(mongocrypt_t *crypt);

/**
 * DEPRECATED: Use of `mongocrypt_setopt_use_range_v2` is deprecated. Range V2 is always enabled.
 *
 * @param[in] crypt The @ref mongocrypt_t object.
 *
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_use_range_v2(mongocrypt_t *crypt);

/**
 * Set the contention factor used for explicit encryption.
 * The contention factor is only used for indexed Queryable Encryption.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] contention_factor
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_contention_factor(mongocrypt_ctx_t *ctx, int64_t contention_factor);

/**
 * Set the index key id to use for explicit Queryable Encryption.
 *
 * If the index key id not set, the key id from @ref
 * mongocrypt_ctx_setopt_key_id is used.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] key_id The binary corresponding to the _id (a UUID) of the data
 * key to use from the key vault collection. Note, the UUID must be encoded with
 * RFC-4122 byte order. The viewed data is copied. It is valid to destroy
 * @p key_id with @ref mongocrypt_binary_destroy immediately after.
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_index_key_id(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *key_id);

/**
 * Set the query type to use for explicit Queryable Encryption.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] query_type The query type string
 * @param[in] len The length of query_type, or -1 for automatic
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_query_type(mongocrypt_ctx_t *ctx, const char *query_type, int len);

/**
 * Set options for explicit encryption with the "range" algorithm.
 *
 * @p opts is a BSON document of the form:
 * {
 *    "min": Optional<BSON value>,
 *    "max": Optional<BSON value>,
 *    "sparsity": Optional<Int64>,
 *    "precision": Optional<Int32>,
 *    "trimFactor": Optional<Int32>
 * }
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] opts BSON.
 * @pre @p ctx has not been initialized.
 * @returns A boolean indicating success. If false, an error status is set.
 * Retrieve it with @ref mongocrypt_ctx_status
 */
MONGOCRYPT_EXPORT
bool mongocrypt_ctx_setopt_algorithm_range(mongocrypt_ctx_t *ctx, mongocrypt_binary_t *opts);

/**
 * Set the expiration time for the data encryption key cache. Defaults to 60 seconds if not set.
 *
 * @param[in] ctx The @ref mongocrypt_ctx_t object.
 * @param[in] cache_expiration_ms The cache expiration time in milliseconds. If zero, the cache
 * never expires.
 */
MONGOCRYPT_EXPORT
bool mongocrypt_setopt_key_expiration(mongocrypt_t *crypt, uint64_t cache_expiration_ms);

/// String constants for setopt_query_type
#define MONGOCRYPT_QUERY_TYPE_EQUALITY_STR "equality"
// DEPRECATED: Support "rangePreview" has been removed in favor of "range".
#define MONGOCRYPT_QUERY_TYPE_RANGEPREVIEW_DEPRECATED_STR "rangePreview"
#define MONGOCRYPT_QUERY_TYPE_RANGE_STR "range"
/// NOTE: "substringPreview" is experimental and may be removed in a future non-major release.
#define MONGOCRYPT_QUERY_TYPE_SUBSTRINGPREVIEW_STR "substringPreview"
/// NOTE: "suffixPreview" is experimental and may be removed in a future non-major release.
#define MONGOCRYPT_QUERY_TYPE_SUFFIXPREVIEW_STR "suffixPreview"
/// NOTE: "prefixPreview" is experimental and may be removed in a future non-major release.
#define MONGOCRYPT_QUERY_TYPE_PREFIXPREVIEW_STR "prefixPreview"

#endif /* MONGOCRYPT_H */