/*

 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (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 <errno.h>

#include "bio_local.h"

#ifndef OPENSSL_NO_SOCK

typedef struct bio_connect_st {

    int state;

    int connect_family;

    char *param_hostname;

    char *param_service;

    int connect_mode;

    BIO_ADDRINFO *addr_first;

    const BIO_ADDRINFO *addr_iter;

    /*

     * int socket; this will be kept in bio->num so that it is compatible

     * with the bss_sock bio

     */

    /*

     * called when the connection is initially made callback(BIO,state,ret);

     * The callback should return 'ret'.  state is for compatibility with the

     * ssl info_callback

     */

    BIO_info_cb *info_callback;

} BIO_CONNECT;

static int conn_write(BIO *h, const char *buf, int num);

static int conn_read(BIO *h, char *buf, int size);

static int conn_puts(BIO *h, const char *str);

static long conn_ctrl(BIO *h, int cmd, long arg1, void *arg2);

static int conn_new(BIO *h);

static int conn_free(BIO *data);

static long conn_callback_ctrl(BIO *h, int cmd, BIO_info_cb *);

static int conn_state(BIO *b, BIO_CONNECT *c);

static void conn_close_socket(BIO *data);

BIO_CONNECT *BIO_CONNECT_new(void);

void BIO_CONNECT_free(BIO_CONNECT *a);

#define BIO_CONN_S_BEFORE                1

#define BIO_CONN_S_GET_ADDR              2

#define BIO_CONN_S_CREATE_SOCKET         3

#define BIO_CONN_S_CONNECT               4

#define BIO_CONN_S_OK                    5

#define BIO_CONN_S_BLOCKED_CONNECT       6

#define BIO_CONN_S_CONNECT_ERROR         7

static const BIO_METHOD methods_connectp = {

    BIO_TYPE_CONNECT,

    "socket connect",

    /* TODO: Convert to new style write function */

    bwrite_conv,

    conn_write,

    /* TODO: Convert to new style read function */

    bread_conv,

    conn_read,

    conn_puts,

    NULL,                       /* conn_gets, */

    conn_ctrl,

    conn_new,

    conn_free,

    conn_callback_ctrl,

};

static int conn_state(BIO *b, BIO_CONNECT *c)

{

    int ret = -1, i;

    BIO_info_cb *cb = NULL;

    if (c->info_callback != NULL)

        cb = c->info_callback;

    for (;;) {

        switch (c->state) {

        case BIO_CONN_S_BEFORE:

            if (c->param_hostname == NULL && c->param_service == NULL) {

                BIOerr(BIO_F_CONN_STATE, BIO_R_NO_HOSTNAME_OR_SERVICE_SPECIFIED);

                ERR_add_error_data(4,

                                   "hostname=", c->param_hostname,

                                   " service=", c->param_service);

                goto exit_loop;

            }

            c->state = BIO_CONN_S_GET_ADDR;

            break;

        case BIO_CONN_S_GET_ADDR:

            {

                int family = AF_UNSPEC;

                switch (c->connect_family) {

                case BIO_FAMILY_IPV6:

                    if (1) { /* This is a trick we use to avoid bit rot.

                              * at least the "else" part will always be

                              * compiled.

                              */

#ifdef AF_INET6

                        family = AF_INET6;

                    } else {

#endif

                        BIOerr(BIO_F_CONN_STATE, BIO_R_UNAVAILABLE_IP_FAMILY);

                        goto exit_loop;

                    }

                    break;

                case BIO_FAMILY_IPV4:

                    family = AF_INET;

                    break;

                case BIO_FAMILY_IPANY:

                    family = AF_UNSPEC;

                    break;

                default:

                    BIOerr(BIO_F_CONN_STATE, BIO_R_UNSUPPORTED_IP_FAMILY);

                    goto exit_loop;

                }

                if (BIO_lookup(c->param_hostname, c->param_service,

                               BIO_LOOKUP_CLIENT,

                               family, SOCK_STREAM, &c->addr_first) == 0)

                    goto exit_loop;

            }

            if (c->addr_first == NULL) {

                BIOerr(BIO_F_CONN_STATE, BIO_R_LOOKUP_RETURNED_NOTHING);

                goto exit_loop;

            }

            c->addr_iter = c->addr_first;

            c->state = BIO_CONN_S_CREATE_SOCKET;

            break;

        case BIO_CONN_S_CREATE_SOCKET:

            ret = BIO_socket(BIO_ADDRINFO_family(c->addr_iter),

                             BIO_ADDRINFO_socktype(c->addr_iter),

                             BIO_ADDRINFO_protocol(c->addr_iter), 0);

            if (ret == (int)INVALID_SOCKET) {

                SYSerr(SYS_F_SOCKET, get_last_socket_error());

                ERR_add_error_data(4,

                                   "hostname=", c->param_hostname,

                                   " service=", c->param_service);

                BIOerr(BIO_F_CONN_STATE, BIO_R_UNABLE_TO_CREATE_SOCKET);

                goto exit_loop;

            }

            b->num = ret;

            c->state = BIO_CONN_S_CONNECT;

            break;

        case BIO_CONN_S_CONNECT:

            BIO_clear_retry_flags(b);

            ret = BIO_connect(b->num, BIO_ADDRINFO_address(c->addr_iter),

                              BIO_SOCK_KEEPALIVE | c->connect_mode);

            b->retry_reason = 0;

            if (ret == 0) {

                if (BIO_sock_should_retry(ret)) {

                    BIO_set_retry_special(b);

                    c->state = BIO_CONN_S_BLOCKED_CONNECT;

                    b->retry_reason = BIO_RR_CONNECT;

                    ERR_clear_error();

                } else if ((c->addr_iter = BIO_ADDRINFO_next(c->addr_iter))

                           != NULL) {

                    /*

                     * if there are more addresses to try, do that first

                     */

                    BIO_closesocket(b->num);

                    c->state = BIO_CONN_S_CREATE_SOCKET;

                    ERR_clear_error();

                    break;

                } else {

                    SYSerr(SYS_F_CONNECT, get_last_socket_error());

                    ERR_add_error_data(4,

                                       "hostname=", c->param_hostname,

                                       " service=", c->param_service);

                    c->state = BIO_CONN_S_CONNECT_ERROR;

                    break;

                }

                goto exit_loop;

            } else {

                c->state = BIO_CONN_S_OK;

            }

            break;

        case BIO_CONN_S_BLOCKED_CONNECT:

            i = BIO_sock_error(b->num);

            if (i) {

                BIO_clear_retry_flags(b);

                SYSerr(SYS_F_CONNECT, i);

                ERR_add_error_data(4,

                                   "hostname=", c->param_hostname,

                                   " service=", c->param_service);

                BIOerr(BIO_F_CONN_STATE, BIO_R_NBIO_CONNECT_ERROR);

                ret = 0;

                goto exit_loop;

            } else

                c->state = BIO_CONN_S_OK;

            break;

        case BIO_CONN_S_CONNECT_ERROR:

            BIOerr(BIO_F_CONN_STATE, BIO_R_CONNECT_ERROR);

            ret = 0;

            goto exit_loop;

        case BIO_CONN_S_OK:

            ret = 1;

            goto exit_loop;

        default:

            /* abort(); */

            goto exit_loop;

        }

        if (cb != NULL) {

            if ((ret = cb((BIO *)b, c->state, ret)) == 0)

                goto end;

        }

    }

    /* Loop does not exit */

 exit_loop:

    if (cb != NULL)

        ret = cb((BIO *)b, c->state, ret);

 end:

    return ret;

}

BIO_CONNECT *BIO_CONNECT_new(void)

{

    BIO_CONNECT *ret;

    if ((ret = OPENSSL_zalloc(sizeof(*ret))) == NULL) {

        BIOerr(BIO_F_BIO_CONNECT_NEW, ERR_R_MALLOC_FAILURE);

        return NULL;

    }

    ret->state = BIO_CONN_S_BEFORE;

    ret->connect_family = BIO_FAMILY_IPANY;

    return ret;

}

void BIO_CONNECT_free(BIO_CONNECT *a)

{

    if (a == NULL)

        return;

    OPENSSL_free(a->param_hostname);

    OPENSSL_free(a->param_service);

    BIO_ADDRINFO_free(a->addr_first);

    OPENSSL_free(a);

}

const BIO_METHOD *BIO_s_connect(void)

{

    return &methods_connectp;

}

static int conn_new(BIO *bi)

{

    bi->init = 0;

    bi->num = (int)INVALID_SOCKET;

    bi->flags = 0;

    if ((bi->ptr = (char *)BIO_CONNECT_new()) == NULL)

        return 0;

    else

        return 1;

}

static void conn_close_socket(BIO *bio)

{

    BIO_CONNECT *c;

    c = (BIO_CONNECT *)bio->ptr;

    if (bio->num != (int)INVALID_SOCKET) {

        /* Only do a shutdown if things were established */

        if (c->state == BIO_CONN_S_OK)

            shutdown(bio->num, 2);

        BIO_closesocket(bio->num);

        bio->num = (int)INVALID_SOCKET;

    }

}

static int conn_free(BIO *a)

{

    BIO_CONNECT *data;

    if (a == NULL)

        return 0;

    data = (BIO_CONNECT *)a->ptr;

    if (a->shutdown) {

        conn_close_socket(a);

        BIO_CONNECT_free(data);

        a->ptr = NULL;

        a->flags = 0;

        a->init = 0;

    }

    return 1;

}

static int conn_read(BIO *b, char *out, int outl)

{

    int ret = 0;

    BIO_CONNECT *data;

    data = (BIO_CONNECT *)b->ptr;

    if (data->state != BIO_CONN_S_OK) {

        ret = conn_state(b, data);

        if (ret <= 0)

            return ret;

    }

    if (out != NULL) {

        clear_socket_error();

        ret = readsocket(b->num, out, outl);

        BIO_clear_retry_flags(b);

        if (ret <= 0) {

            if (BIO_sock_should_retry(ret))

                BIO_set_retry_read(b);

            else if (ret == 0)

                b->flags |= BIO_FLAGS_IN_EOF;

        }

    }

    return ret;

}

static int conn_write(BIO *b, const char *in, int inl)

{

    int ret;

    BIO_CONNECT *data;

    data = (BIO_CONNECT *)b->ptr;

    if (data->state != BIO_CONN_S_OK) {

        ret = conn_state(b, data);

        if (ret <= 0)

            return ret;

    }

    clear_socket_error();

    ret = writesocket(b->num, in, inl);

    BIO_clear_retry_flags(b);

    if (ret <= 0) {

        if (BIO_sock_should_retry(ret))

            BIO_set_retry_write(b);

    }

    return ret;

}

static long conn_ctrl(BIO *b, int cmd, long num, void *ptr)

{

    BIO *dbio;

    int *ip;

    const char **pptr = NULL;

    long ret = 1;

    BIO_CONNECT *data;

    data = (BIO_CONNECT *)b->ptr;

    switch (cmd) {

    case BIO_CTRL_RESET:

        ret = 0;

        data->state = BIO_CONN_S_BEFORE;

        conn_close_socket(b);

        BIO_ADDRINFO_free(data->addr_first);

        data->addr_first = NULL;

        b->flags = 0;

        break;

    case BIO_C_DO_STATE_MACHINE:

        /* use this one to start the connection */

        if (data->state != BIO_CONN_S_OK)

            ret = (long)conn_state(b, data);

        else

            ret = 1;

        break;

    case BIO_C_GET_CONNECT:

        if (ptr != NULL) {

            pptr = (const char **)ptr;

            if (num == 0) {

                *pptr = data->param_hostname;

            } else if (num == 1) {

                *pptr = data->param_service;

            } else if (num == 2) {

                *pptr = (const char *)BIO_ADDRINFO_address(data->addr_iter);

            } else if (num == 3) {

                switch (BIO_ADDRINFO_family(data->addr_iter)) {

# ifdef AF_INET6

                case AF_INET6:

                    ret = BIO_FAMILY_IPV6;

                    break;

# endif

                case AF_INET:

                    ret = BIO_FAMILY_IPV4;

                    break;

                case 0:

                    ret = data->connect_family;

                    break;

                default:

                    ret = -1;

                    break;

                }

            } else {

                ret = 0;

            }

        } else {

            ret = 0;

        }

        break;

    case BIO_C_SET_CONNECT:

        if (ptr != NULL) {

            b->init = 1;

            if (num == 0) {

                char *hold_service = data->param_service;

                /* We affect the hostname regardless.  However, the input

                 * string might contain a host:service spec, so we must

                 * parse it, which might or might not affect the service

                 */

                OPENSSL_free(data->param_hostname);

                data->param_hostname = NULL;

                ret = BIO_parse_hostserv(ptr,

                                         &data->param_hostname,

                                         &data->param_service,

                                         BIO_PARSE_PRIO_HOST);

                if (hold_service != data->param_service)

                    OPENSSL_free(hold_service);

            } else if (num == 1) {

                OPENSSL_free(data->param_service);

                data->param_service = BUF_strdup(ptr);

            } else if (num == 2) {

                const BIO_ADDR *addr = (const BIO_ADDR *)ptr;

                if (ret) {

                    data->param_hostname = BIO_ADDR_hostname_string(addr, 1);

                    data->param_service = BIO_ADDR_service_string(addr, 1);

                    BIO_ADDRINFO_free(data->addr_first);

                    data->addr_first = NULL;

                    data->addr_iter = NULL;

                }

            } else if (num == 3) {

                data->connect_family = *(int *)ptr;

            } else {

                ret = 0;

            }

        }

        break;

    case BIO_C_SET_NBIO:

        if (num != 0)

            data->connect_mode |= BIO_SOCK_NONBLOCK;

        else

            data->connect_mode &= ~BIO_SOCK_NONBLOCK;

        break;

    case BIO_C_SET_CONNECT_MODE:

        data->connect_mode = (int)num;

        break;

    case BIO_C_GET_FD:

        if (b->init) {

            ip = (int *)ptr;

            if (ip != NULL)

                *ip = b->num;

            ret = b->num;

        } else

            ret = -1;

        break;

    case BIO_CTRL_GET_CLOSE:

        ret = b->shutdown;

        break;

    case BIO_CTRL_SET_CLOSE:

        b->shutdown = (int)num;

        break;

    case BIO_CTRL_PENDING:

    case BIO_CTRL_WPENDING:

        ret = 0;

        break;

    case BIO_CTRL_FLUSH:

        break;

    case BIO_CTRL_DUP:

        {

            dbio = (BIO *)ptr;

            if (data->param_hostname)

                BIO_set_conn_hostname(dbio, data->param_hostname);

            if (data->param_service)

                BIO_set_conn_port(dbio, data->param_service);

            BIO_set_conn_ip_family(dbio, data->connect_family);

            BIO_set_conn_mode(dbio, data->connect_mode);

            /*

             * FIXME: the cast of the function seems unlikely to be a good

             * idea

             */

            (void)BIO_set_info_callback(dbio, data->info_callback);

        }

        break;

    case BIO_CTRL_SET_CALLBACK:

        ret = 0; /* use callback ctrl */

        break;

    case BIO_CTRL_GET_CALLBACK:

        {

            BIO_info_cb **fptr;

            fptr = (BIO_info_cb **)ptr;

            *fptr = data->info_callback;

        }

        break;

    case BIO_CTRL_EOF:

        ret = (b->flags & BIO_FLAGS_IN_EOF) != 0 ? 1 : 0;

        break;

    default:

        ret = 0;

        break;

    }

    return ret;

}

static long conn_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp)

{

    long ret = 1;

    BIO_CONNECT *data;

    data = (BIO_CONNECT *)b->ptr;

    switch (cmd) {

    case BIO_CTRL_SET_CALLBACK:

        {

            data->info_callback = fp;

        }

        break;

    default:

        ret = 0;

        break;

    }

    return ret;

}

static int conn_puts(BIO *bp, const char *str)

{

    int n, ret;

    n = strlen(str);

    ret = conn_write(bp, str, n);

    return ret;

}

BIO *BIO_new_connect(const char *str)

{

    BIO *ret;

    ret = BIO_new(BIO_s_connect());

    if (ret == NULL)

        return NULL;

    if (BIO_set_conn_hostname(ret, str))

        return ret;

    BIO_free(ret);

    return NULL;

}

#endif