/*

 * Copyright 2016-2022 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <stdio.h>

#include <stdlib.h>

#include <errno.h>

#include "bio_local.h"

#include "internal/ktls.h"

#include "internal/bio_tfo.h"

#include <openssl/err.h>

#ifndef OPENSSL_NO_SOCK

#ifdef SO_MAXCONN

#define MAX_LISTEN SO_MAXCONN

#elif defined(SOMAXCONN)

#define MAX_LISTEN SOMAXCONN

#else

#define MAX_LISTEN 32

#endif

/*-

 * BIO_socket - create a socket

 * @domain: the socket domain (AF_INET, AF_INET6, AF_UNIX, ...)

 * @socktype: the socket type (SOCK_STEAM, SOCK_DGRAM)

 * @protocol: the protocol to use (IPPROTO_TCP, IPPROTO_UDP)

 * @options: BIO socket options (currently unused)

 *

 * Creates a socket.  This should be called before calling any

 * of BIO_connect and BIO_listen.

 *

 * Returns the file descriptor on success or INVALID_SOCKET on failure.  On

 * failure errno is set, and a status is added to the OpenSSL error stack.

 */

int BIO_socket(int domain, int socktype, int protocol, int options)

{

    int sock = -1;

    if (BIO_sock_init() != 1)

        return INVALID_SOCKET;

    sock = socket(domain, socktype, protocol);

    if (sock == -1) {

        ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

            "calling socket()");

        ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_CREATE_SOCKET);

        return INVALID_SOCKET;

    }

    return sock;

}

/*-

 * BIO_connect - connect to an address

 * @sock: the socket to connect with

 * @addr: the address to connect to

 * @options: BIO socket options

 *

 * Connects to the address using the given socket and options.

 *

 * Options can be a combination of the following:

 * - BIO_SOCK_KEEPALIVE: enable regularly sending keep-alive messages.

 * - BIO_SOCK_NONBLOCK: Make the socket non-blocking.

 * - BIO_SOCK_NODELAY: don't delay small messages.

 * - BIO_SOCK_TFO: use TCP Fast Open

 *

 * options holds BIO socket options that can be used

 * You should call this for every address returned by BIO_lookup

 * until the connection is successful.

 *

 * Returns 1 on success or 0 on failure.  On failure errno is set

 * and an error status is added to the OpenSSL error stack.

 */

int BIO_connect(int sock, const BIO_ADDR *addr, int options)

{

    const int on = 1;

    if (sock == -1) {

        ERR_raise(ERR_LIB_BIO, BIO_R_INVALID_SOCKET);

        return 0;

    }

    if (!BIO_socket_nbio(sock, (options & BIO_SOCK_NONBLOCK) != 0))

        return 0;

    if (options & BIO_SOCK_KEEPALIVE) {

        if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,

                (const void *)&on, sizeof(on))

            != 0) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling setsockopt()");

            ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_KEEPALIVE);

            return 0;

        }

    }

    if (options & BIO_SOCK_NODELAY) {

        if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,

                (const void *)&on, sizeof(on))

            != 0) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling setsockopt()");

            ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_NODELAY);

            return 0;

        }

    }

    if (options & BIO_SOCK_TFO) {

#if defined(OSSL_TFO_CLIENT_FLAG)

#if defined(OSSL_TFO_SYSCTL_CLIENT)

        int enabled = 0;

        size_t enabledlen = sizeof(enabled);

        /* Later FreeBSD */

        if (sysctlbyname(OSSL_TFO_SYSCTL_CLIENT, &enabled, &enabledlen, NULL, 0) < 0) {

            ERR_raise(ERR_LIB_BIO, BIO_R_TFO_NO_KERNEL_SUPPORT);

            return 0;

        }

        /* Need to check for client flag */

        if (!(enabled & OSSL_TFO_CLIENT_FLAG)) {

            ERR_raise(ERR_LIB_BIO, BIO_R_TFO_DISABLED);

            return 0;

        }

#elif defined(OSSL_TFO_SYSCTL)

        int enabled = 0;

        size_t enabledlen = sizeof(enabled);

        /* macOS */

        if (sysctlbyname(OSSL_TFO_SYSCTL, &enabled, &enabledlen, NULL, 0) < 0) {

            ERR_raise(ERR_LIB_BIO, BIO_R_TFO_NO_KERNEL_SUPPORT);

            return 0;

        }

        /* Need to check for client flag */

        if (!(enabled & OSSL_TFO_CLIENT_FLAG)) {

            ERR_raise(ERR_LIB_BIO, BIO_R_TFO_DISABLED);

            return 0;

        }

#endif

#endif

#if defined(OSSL_TFO_CONNECTX)

        sa_endpoints_t sae;

        memset(&sae, 0, sizeof(sae));

        sae.sae_dstaddr = BIO_ADDR_sockaddr(addr);

        sae.sae_dstaddrlen = BIO_ADDR_sockaddr_size(addr);

        if (connectx(sock, &sae, SAE_ASSOCID_ANY,

                CONNECT_DATA_IDEMPOTENT | CONNECT_RESUME_ON_READ_WRITE,

                NULL, 0, NULL, NULL)

            == -1) {

            if (!BIO_sock_should_retry(-1)) {

                ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                    "calling connectx()");

                ERR_raise(ERR_LIB_BIO, BIO_R_CONNECT_ERROR);

            }

            return 0;

        }

#endif

#if defined(OSSL_TFO_CLIENT_SOCKOPT)

        if (setsockopt(sock, IPPROTO_TCP, OSSL_TFO_CLIENT_SOCKOPT,

                (const void *)&on, sizeof(on))

            != 0) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling setsockopt()");

            ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_TFO);

            return 0;

        }

#endif

#if defined(OSSL_TFO_DO_NOT_CONNECT)

        return 1;

#endif

    }

    if (connect(sock, BIO_ADDR_sockaddr(addr),

            BIO_ADDR_sockaddr_size(addr))

        == -1) {

        if (!BIO_sock_should_retry(-1)) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling connect()");

            ERR_raise(ERR_LIB_BIO, BIO_R_CONNECT_ERROR);

        }

        return 0;

    }

    return 1;

}

/*-

 * BIO_bind - bind socket to address

 * @sock: the socket to set

 * @addr: local address to bind to

 * @options: BIO socket options

 *

 * Binds to the address using the given socket and options.

 *

 * Options can be a combination of the following:

 * - BIO_SOCK_REUSEADDR: Try to reuse the address and port combination

 *   for a recently closed port.

 *

 * When restarting the program it could be that the port is still in use.  If

 * you set to BIO_SOCK_REUSEADDR option it will try to reuse the port anyway.

 * It's recommended that you use this.

 */

int BIO_bind(int sock, const BIO_ADDR *addr, int options)

{

#ifndef OPENSSL_SYS_WINDOWS

    int on = 1;

#endif

    if (sock == -1) {

        ERR_raise(ERR_LIB_BIO, BIO_R_INVALID_SOCKET);

        return 0;

    }

#ifndef OPENSSL_SYS_WINDOWS

    /*

     * SO_REUSEADDR has different behavior on Windows than on

     * other operating systems, don't set it there.

     */

    if (options & BIO_SOCK_REUSEADDR) {

        if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,

                (const void *)&on, sizeof(on))

            != 0) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling setsockopt()");

            ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_REUSEADDR);

            return 0;

        }

    }

#endif

    if (bind(sock, BIO_ADDR_sockaddr(addr), BIO_ADDR_sockaddr_size(addr)) != 0) {

        ERR_raise_data(ERR_LIB_SYS, get_last_socket_error() /* may be 0 */,

            "calling bind()");

        ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_BIND_SOCKET);

        return 0;

    }

    return 1;

}

/*-

 * BIO_listen - Creates a listen socket

 * @sock: the socket to listen with

 * @addr: local address to bind to

 * @options: BIO socket options

 *

 * Binds to the address using the given socket and options, then

 * starts listening for incoming connections.

 *

 * Options can be a combination of the following:

 * - BIO_SOCK_KEEPALIVE: enable regularly sending keep-alive messages.

 * - BIO_SOCK_NONBLOCK: Make the socket non-blocking.

 * - BIO_SOCK_NODELAY: don't delay small messages.

 * - BIO_SOCK_REUSEADDR: Try to reuse the address and port combination

 *   for a recently closed port.

 * - BIO_SOCK_V6_ONLY: When creating an IPv6 socket, make it listen only

 *   for IPv6 addresses and not IPv4 addresses mapped to IPv6.

 * - BIO_SOCK_TFO: accept TCP fast open (set TCP_FASTOPEN)

 *

 * It's recommended that you set up both an IPv6 and IPv4 listen socket, and

 * then check both for new clients that connect to it.  You want to set up

 * the socket as non-blocking in that case since else it could hang.

 *

 * Not all operating systems support IPv4 addresses on an IPv6 socket, and for

 * others it's an option.  If you pass the BIO_LISTEN_V6_ONLY it will try to

 * create the IPv6 sockets to only listen for IPv6 connection.

 *

 * It could be that the first BIO_listen() call will listen to all the IPv6

 * and IPv4 addresses and that then trying to bind to the IPv4 address will

 * fail.  We can't tell the difference between already listening ourself to

 * it and someone else listening to it when failing and errno is EADDRINUSE, so

 * it's recommended to not give an error in that case if the first call was

 * successful.

 *

 * When restarting the program it could be that the port is still in use.  If

 * you set to BIO_SOCK_REUSEADDR option it will try to reuse the port anyway.

 * It's recommended that you use this.

 */

int BIO_listen(int sock, const BIO_ADDR *addr, int options)

{

    int on = 1;

    int socktype;

    socklen_t socktype_len = sizeof(socktype);

    if (sock == -1) {

        ERR_raise(ERR_LIB_BIO, BIO_R_INVALID_SOCKET);

        return 0;

    }

    if (getsockopt(sock, SOL_SOCKET, SO_TYPE,

            (void *)&socktype, &socktype_len)

            != 0

        || socktype_len != sizeof(socktype)) {

        ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

            "calling getsockopt()");

        ERR_raise(ERR_LIB_BIO, BIO_R_GETTING_SOCKTYPE);

        return 0;

    }

    if (!BIO_socket_nbio(sock, (options & BIO_SOCK_NONBLOCK) != 0))

        return 0;

    if (options & BIO_SOCK_KEEPALIVE) {

        if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,

                (const void *)&on, sizeof(on))

            != 0) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling setsockopt()");

            ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_KEEPALIVE);

            return 0;

        }

    }

    if (options & BIO_SOCK_NODELAY) {

        if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,

                (const void *)&on, sizeof(on))

            != 0) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling setsockopt()");

            ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_NODELAY);

            return 0;

        }

    }

    /* On OpenBSD it is always IPv6 only with IPv6 sockets thus read-only */

#if defined(IPV6_V6ONLY) && !defined(__OpenBSD__)

    if (BIO_ADDR_family(addr) == AF_INET6) {

        /*

         * Note: Windows default of IPV6_V6ONLY is ON, and Linux is OFF.

         * Therefore we always have to use setsockopt here.

         */

        on = options & BIO_SOCK_V6_ONLY ? 1 : 0;

        if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY,

                (const void *)&on, sizeof(on))

            != 0) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling setsockopt()");

            ERR_raise(ERR_LIB_BIO, BIO_R_LISTEN_V6_ONLY);

            return 0;

        }

    }

#endif

    if (!BIO_bind(sock, addr, options))

        return 0;

    if (socktype != SOCK_DGRAM && listen(sock, MAX_LISTEN) == -1) {

        ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

            "calling listen()");

        ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_LISTEN_SOCKET);

        return 0;

    }

#if defined(OSSL_TFO_SERVER_SOCKOPT)

    /*

     * Must do it explicitly after listen() for macOS, still

     * works fine on other OS's

     */

    if ((options & BIO_SOCK_TFO) && socktype != SOCK_DGRAM) {

        int q = OSSL_TFO_SERVER_SOCKOPT_VALUE;

#if defined(OSSL_TFO_CLIENT_FLAG)

#if defined(OSSL_TFO_SYSCTL_SERVER)

        int enabled = 0;

        size_t enabledlen = sizeof(enabled);

        /* Later FreeBSD */

        if (sysctlbyname(OSSL_TFO_SYSCTL_SERVER, &enabled, &enabledlen, NULL, 0) < 0) {

            ERR_raise(ERR_LIB_BIO, BIO_R_TFO_NO_KERNEL_SUPPORT);

            return 0;

        }

        /* Need to check for server flag */

        if (!(enabled & OSSL_TFO_SERVER_FLAG)) {

            ERR_raise(ERR_LIB_BIO, BIO_R_TFO_DISABLED);

            return 0;

        }

#elif defined(OSSL_TFO_SYSCTL)

        int enabled = 0;

        size_t enabledlen = sizeof(enabled);

        /* Early FreeBSD, macOS */

        if (sysctlbyname(OSSL_TFO_SYSCTL, &enabled, &enabledlen, NULL, 0) < 0) {

            ERR_raise(ERR_LIB_BIO, BIO_R_TFO_NO_KERNEL_SUPPORT);

            return 0;

        }

        /* Need to check for server flag */

        if (!(enabled & OSSL_TFO_SERVER_FLAG)) {

            ERR_raise(ERR_LIB_BIO, BIO_R_TFO_DISABLED);

            return 0;

        }

#endif

#endif

        if (setsockopt(sock, IPPROTO_TCP, OSSL_TFO_SERVER_SOCKOPT,

                (void *)&q, sizeof(q))

            < 0) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling setsockopt()");

            ERR_raise(ERR_LIB_BIO, BIO_R_UNABLE_TO_TFO);

            return 0;

        }

    }

#endif

    return 1;

}

/*-

 * BIO_accept_ex - Accept new incoming connections

 * @sock: the listening socket

 * @addr: the BIO_ADDR to store the peer address in

 * @options: BIO socket options, applied on the accepted socket.

 *

 */

int BIO_accept_ex(int accept_sock, BIO_ADDR *addr_, int options)

{

    socklen_t len;

    int accepted_sock;

    BIO_ADDR locaddr;

    BIO_ADDR *addr = addr_ == NULL ? &locaddr : addr_;

    len = sizeof(*addr);

    accepted_sock = accept(accept_sock,

        BIO_ADDR_sockaddr_noconst(addr), &len);

    if (accepted_sock == -1) {

        if (!BIO_sock_should_retry(accepted_sock)) {

            ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),

                "calling accept()");

            ERR_raise(ERR_LIB_BIO, BIO_R_ACCEPT_ERROR);

        }

        return INVALID_SOCKET;

    }

    if (!BIO_socket_nbio(accepted_sock, (options & BIO_SOCK_NONBLOCK) != 0)) {

        closesocket(accepted_sock);

        return INVALID_SOCKET;

    }

    return accepted_sock;

}

/*-

 * BIO_closesocket - Close a socket

 * @sock: the socket to close

 */

int BIO_closesocket(int sock)

{

    if (sock < 0 || closesocket(sock) < 0)

        return 0;

    return 1;

}

#endif