sudo/logsrvd/logsrvd.h

/*
 * SPDX-License-Identifier: ISC
 *
 * Copyright (c) 2019-2021 Todd C. Miller <Todd.Miller@sudo.ws>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef SUDO_LOGSRVD_H
#define SUDO_LOGSRVD_H

#if PROTOBUF_C_VERSION_NUMBER < 1003000
# error protobuf-c version 1.30 or higher required
#endif

#include "config.h"

#if defined(HAVE_OPENSSL)
# include <openssl/ssl.h>
#endif

#include "logsrv_util.h"
#include "tls_common.h"

/* Default timeout value for server socket */
#define DEFAULT_SOCKET_TIMEOUT_SEC 30

/* How often to send an ACK to the client (commit point) in seconds */
#define ACK_FREQUENCY	10

/* Shutdown timeout (in seconds) in case client connections time out. */
#define SHUTDOWN_TIMEO	10

/*
 * Connection status.
 * In the RUNNING state we expect I/O log buffers.
 */
enum connection_status {
    INITIAL,
    CONNECTING,
    RUNNING,
    EXITED,
    SHUTDOWN,
    FINISHED,
    ERROR
};

/*
 * Per-connection relay state.
 */
struct relay_closure {
    struct server_address_list *relays;
    struct server_address *relay_addr;
    struct sudo_event *read_ev;
    struct sudo_event *write_ev;
    struct sudo_event *connect_ev;
    struct connection_buffer read_buf;
    struct connection_buffer_list write_bufs;
    struct peer_info relay_name;
#if defined(HAVE_OPENSSL)
    struct tls_client_closure tls_client;
#endif
    int sock;
    bool read_instead_of_write;
    bool write_instead_of_read;
    bool temporary_write_event;
};

/*
 * Per-connection state.
 */
struct connection_closure {
    TAILQ_ENTRY(connection_closure) entries;
    struct relay_closure *relay_closure;
    struct eventlog *evlog;
    struct timespec elapsed_time;
    struct connection_buffer read_buf;
    struct connection_buffer_list write_bufs;
    struct connection_buffer_list free_bufs;
    struct sudo_event_base *evbase;
    struct sudo_event *commit_ev;
    struct sudo_event *read_ev;
    struct sudo_event *write_ev;
#if defined(HAVE_OPENSSL)
    struct sudo_event *ssl_accept_ev;
    SSL *ssl;
#endif
    const char *errstr;
    struct iolog_file iolog_files[IOFD_MAX];
    int iolog_dir_fd;
    int sock;
    enum connection_status state;
    bool tls;
    bool log_io;
    bool read_instead_of_write;
    bool write_instead_of_read;
    bool temporary_write_event;
#ifdef HAVE_STRUCT_IN6_ADDR
    char ipaddr[INET6_ADDRSTRLEN];
#else
    char ipaddr[INET_ADDRSTRLEN];
#endif
};

union sockaddr_union {
    struct sockaddr sa;
    struct sockaddr_in sin;
#ifdef HAVE_STRUCT_IN6_ADDR
    struct sockaddr_in6 sin6;
#endif
};

/*
 * List of server addresses.
 */
struct server_address {
    TAILQ_ENTRY(server_address) entries;
    char *sa_host;
    char *sa_str;
    union sockaddr_union sa_un;
    socklen_t sa_size;
    bool tls;
};
TAILQ_HEAD(server_address_list, server_address);

/*
 * List of active network listeners.
 */
struct listener {
    TAILQ_ENTRY(listener) entries;
    struct sudo_event *ev;
    int sock;
    bool tls;
};
TAILQ_HEAD(listener_list, listener);

/* iolog_writer.c */
struct eventlog *evlog_new(TimeSpec *submit_time, InfoMessage **info_msgs, size_t infolen, struct connection_closure *closure);
bool iolog_init(AcceptMessage *msg, struct connection_closure *closure);
bool iolog_restart(RestartMessage *msg, struct connection_closure *closure);
int store_iobuf(int iofd, IoBuffer *msg, struct connection_closure *closure);
int store_suspend(CommandSuspend *msg, struct connection_closure *closure);
int store_winsize(ChangeWindowSize *msg, struct connection_closure *closure);
void iolog_close_all(struct connection_closure *closure);

/* logsrvd.c */
bool start_protocol(struct connection_closure *closure);
void connection_closure_free(struct connection_closure *closure);
bool schedule_commit_point(TimeSpec *commit_point, struct connection_closure *closure);
bool fmt_log_id_message(const char *id, struct connection_closure *closure);
bool fmt_error_message(const char *errstr, struct connection_closure *closure);
struct connection_buffer *get_free_buf(struct connection_closure *closure);

/* logsrvd_conf.c */
bool logsrvd_conf_read(const char *path);
const char *logsrvd_conf_iolog_dir(void);
const char *logsrvd_conf_iolog_file(void);
struct server_address_list *logsrvd_conf_server_listen_address(void);
struct server_address_list *logsrvd_conf_relay_address(void);
bool logsrvd_conf_relay_tcp_keepalive(void);
bool logsrvd_conf_server_tcp_keepalive(void);
const char *logsrvd_conf_pid_file(void);
struct timespec *logsrvd_conf_server_timeout(void);
struct timespec *logsrvd_conf_relay_connect_timeout(void);
struct timespec *logsrvd_conf_relay_timeout(void);
#if defined(HAVE_OPENSSL)
bool logsrvd_conf_server_tls_check_peer(void);
SSL_CTX *logsrvd_server_tls_ctx(void);
bool logsrvd_conf_relay_tls_check_peer(void);
SSL_CTX *logsrvd_relay_tls_ctx(void);
#endif
mode_t logsrvd_conf_iolog_mode(void);
void address_list_addref(struct server_address_list *);
void address_list_delref(struct server_address_list *);
void logsrvd_conf_cleanup(void);

/* logsrvd_relay.c */
void relay_closure_free(struct relay_closure *relay_closure);
bool connect_relay(struct connection_closure *closure);
bool relay_accept(AcceptMessage *msg, struct connection_closure *closure);
bool relay_reject(RejectMessage *msg, struct connection_closure *closure);
bool relay_exit(ExitMessage *msg, struct connection_closure *closure);
bool relay_restart(RestartMessage *msg, struct connection_closure *closure);
bool relay_alert(AlertMessage *msg, struct connection_closure *closure);
bool relay_iobuf(int iofd, IoBuffer *iobuf, struct connection_closure *closure);
bool relay_shutdown(struct connection_closure *closure);

#endif /* SUDO_LOGSRVD_H */