xref: /openbsd-src/lib/libcrypto/bio/bss_conn.c (revision 80f19918c99cbc942396fe67c189adf1eb521ed1)

/* $OpenBSD: bss_conn.c,v 1.41 2024/04/19 09:54:36 tb Exp $ */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <sys/socket.h>

#include <netinet/in.h>

#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#include <openssl/bio.h>
#include <openssl/buffer.h>
#include <openssl/err.h>

#include "bio_local.h"

#define SOCKET_PROTOCOL IPPROTO_TCP

typedef struct bio_connect_st {
	int state;

	char *param_hostname;
	char *param_port;
	int nbio;

	unsigned char ip[4];
	unsigned short port;

	struct sockaddr_in them;

	/* 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);
static BIO_CONNECT *BIO_CONNECT_new(void);
static void BIO_CONNECT_free(BIO_CONNECT *a);

static const BIO_METHOD methods_connectp = {
	.type = BIO_TYPE_CONNECT,
	.name = "socket connect",
	.bwrite = conn_write,
	.bread = conn_read,
	.bputs = conn_puts,
	.ctrl = conn_ctrl,
	.create = conn_new,
	.destroy = conn_free,
	.callback_ctrl = conn_callback_ctrl
};

static int
conn_state(BIO *b, BIO_CONNECT *c)
{
	int ret = -1, i;
	unsigned long l;
	char *p, *q;
	BIO_info_cb *cb = NULL;

	if (c->info_callback != NULL)
		cb = c->info_callback;

	for (;;) {
		switch (c->state) {
		case BIO_CONN_S_BEFORE:
			p = c->param_hostname;
			if (p == NULL) {
				BIOerror(BIO_R_NO_HOSTNAME_SPECIFIED);
				goto exit_loop;
			}
			for (; *p != '\0'; p++) {
				if ((*p == ':') || (*p == '/'))
				break;
			}

			i= *p;
			if ((i == ':') || (i == '/')) {
				*(p++) = '\0';
				if (i == ':') {
					for (q = p; *q; q++)
						if (*q == '/') {
							*q = '\0';
							break;
						}
					free(c->param_port);
					c->param_port = strdup(p);
				}
			}

			if (c->param_port == NULL) {
				BIOerror(BIO_R_NO_PORT_SPECIFIED);
				ERR_asprintf_error_data("host=%s",
				    c->param_hostname);
				goto exit_loop;
			}
			c->state = BIO_CONN_S_GET_IP;
			break;

		case BIO_CONN_S_GET_IP:
			if (BIO_get_host_ip(c->param_hostname, &(c->ip[0])) <= 0)
				goto exit_loop;
			c->state = BIO_CONN_S_GET_PORT;
			break;

		case BIO_CONN_S_GET_PORT:
			if (c->param_port == NULL) {
				/* abort(); */
				goto exit_loop;
			} else if (BIO_get_port(c->param_port, &c->port) <= 0)
				goto exit_loop;
			c->state = BIO_CONN_S_CREATE_SOCKET;
			break;

		case BIO_CONN_S_CREATE_SOCKET:
			/* now setup address */
			memset((char *)&c->them, 0, sizeof(c->them));
			c->them.sin_family = AF_INET;
			c->them.sin_port = htons((unsigned short)c->port);
			l = (unsigned long)
			    ((unsigned long)c->ip[0] << 24L)|
			    ((unsigned long)c->ip[1] << 16L)|
			    ((unsigned long)c->ip[2] << 8L)|
			    ((unsigned long)c->ip[3]);
			c->them.sin_addr.s_addr = htonl(l);
			c->state = BIO_CONN_S_CREATE_SOCKET;

			ret = socket(AF_INET, SOCK_STREAM, SOCKET_PROTOCOL);
			if (ret == -1) {
				SYSerror(errno);
				ERR_asprintf_error_data("host=%s:%s",
				    c->param_hostname, c->param_port);
				BIOerror(BIO_R_UNABLE_TO_CREATE_SOCKET);
				goto exit_loop;
			}
			b->num = ret;
			c->state = BIO_CONN_S_NBIO;
			break;

		case BIO_CONN_S_NBIO:
			if (c->nbio) {
				if (!BIO_socket_nbio(b->num, 1)) {
					BIOerror(BIO_R_ERROR_SETTING_NBIO);
					ERR_asprintf_error_data("host=%s:%s",
					    c->param_hostname, c->param_port);
					goto exit_loop;
				}
			}
			c->state = BIO_CONN_S_CONNECT;

#if defined(SO_KEEPALIVE)
			i = 1;
			i = setsockopt(b->num, SOL_SOCKET, SO_KEEPALIVE, &i, sizeof(i));
			if (i < 0) {
				SYSerror(errno);
				ERR_asprintf_error_data("host=%s:%s",
				    c->param_hostname, c->param_port);
				BIOerror(BIO_R_KEEPALIVE);
				goto exit_loop;
			}
#endif
			break;

		case BIO_CONN_S_CONNECT:
			BIO_clear_retry_flags(b);
			ret = connect(b->num,
			(struct sockaddr *)&c->them,
			sizeof(c->them));
			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;
				} else {
					SYSerror(errno);
					ERR_asprintf_error_data("host=%s:%s",
					    c->param_hostname, c->param_port);
					BIOerror(BIO_R_CONNECT_ERROR);
				}
				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);
				SYSerror(i);
				ERR_asprintf_error_data("host=%s:%s",
				    c->param_hostname, c->param_port);
				BIOerror(BIO_R_NBIO_CONNECT_ERROR);
				ret = 0;
				goto exit_loop;
			} else
				c->state = BIO_CONN_S_OK;
			break;

		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)))
				goto end;
		}
	}

	/* Loop does not exit */
exit_loop:
	if (cb != NULL)
		ret = cb((BIO *)b, c->state, ret);
end:
	return (ret);
}

static BIO_CONNECT *
BIO_CONNECT_new(void)
{
	BIO_CONNECT *ret;

	if ((ret = malloc(sizeof(BIO_CONNECT))) == NULL)
		return (NULL);
	ret->state = BIO_CONN_S_BEFORE;
	ret->param_hostname = NULL;
	ret->param_port = NULL;
	ret->info_callback = NULL;
	ret->nbio = 0;
	ret->ip[0] = 0;
	ret->ip[1] = 0;
	ret->ip[2] = 0;
	ret->ip[3] = 0;
	ret->port = 0;
	memset((char *)&ret->them, 0, sizeof(ret->them));
	return (ret);
}

static void
BIO_CONNECT_free(BIO_CONNECT *a)
{
	if (a == NULL)
		return;

	free(a->param_hostname);
	free(a->param_port);
	free(a);
}

const BIO_METHOD *
BIO_s_connect(void)
{
	return (&methods_connectp);
}
LCRYPTO_ALIAS(BIO_s_connect);

static int
conn_new(BIO *bi)
{
	bi->init = 0;
	bi->num = -1;
	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 != -1) {
		/* Only do a shutdown if things were established */
		if (c->state == BIO_CONN_S_OK)
			shutdown(bio->num, SHUT_RDWR);
		close(bio->num);
		bio->num = -1;
	}
}

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) {
		errno = 0;
		ret = read(b->num, out, outl);
		BIO_clear_retry_flags(b);
		if (ret <= 0) {
			if (BIO_sock_should_retry(ret))
				BIO_set_retry_read(b);
		}
	}
	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);
	}

	errno = 0;
	ret = write(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;
	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);
		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_port;
			} else if (num == 2) {
				*pptr = (char *)&(data->ip[0]);
			} else if (num == 3) {
				*((int *)ptr) = data->port;
			}
			if ((!b->init) || (ptr == NULL))
				*pptr = "not initialized";
			ret = 1;
		}
		break;
	case BIO_C_SET_CONNECT:
		if (ptr != NULL) {
			b->init = 1;
			if (num == 0) {
				free(data->param_hostname);
				data->param_hostname = strdup(ptr);
			} else if (num == 1) {
				free(data->param_port);
				data->param_port = strdup(ptr);
			} else if (num == 2) {
				unsigned char *p = ptr;
				free(data->param_hostname);
				if (asprintf(&data->param_hostname,
					"%u.%u.%u.%u", p[0], p[1],
					p[2], p[3]) == -1)
					data->param_hostname = NULL;
				memcpy(&(data->ip[0]), ptr, 4);
			} else if (num == 3) {
				free(data->param_port);
				data->port= *(int *)ptr;
				if (asprintf(&data->param_port, "%d",
					data->port) == -1)
					data->param_port = NULL;
			}
		}
		break;
	case BIO_C_SET_NBIO:
		data->nbio = (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_port)
				BIO_set_conn_port(dbio, data->param_port);
			if (data->param_hostname)
				BIO_set_conn_hostname(dbio,
				    data->param_hostname);
			BIO_set_nbio(dbio, data->nbio);
			(void)BIO_set_info_callback(dbio, data->info_callback);
		}
		break;
	case BIO_CTRL_SET_CALLBACK:
		{
#if 0 /* FIXME: Should this be used?  -- Richard Levitte */
			BIOerror(ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
			ret = -1;
#else
			ret = 0;
#endif
		}
		break;
	case BIO_CTRL_GET_CALLBACK:
		{
			BIO_info_cb **fptr = ptr;

			*fptr = data->info_callback;
		}
		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 = (BIO_info_cb *)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);
	else {
		BIO_free(ret);
		return (NULL);
	}
}
LCRYPTO_ALIAS(BIO_new_connect);