C++ BIO_ctrl函数代码示例

int dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
{
    DTLS1_RECORD_DATA *rdata;
    pitem *item;

    /* Limit the size of the queue to prevent DOS attacks */
    if (pqueue_size(queue->q) >= 100)
        return 0;

    rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
    item = pitem_new(priority, rdata);
    if (rdata == NULL || item == NULL) {
        if (rdata != NULL)
            OPENSSL_free(rdata);
        if (item != NULL)
            pitem_free(item);

        SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
        return -1;
    }

    rdata->packet = s->rlayer.packet;
    rdata->packet_length = s->rlayer.packet_length;
    memcpy(&(rdata->rbuf), &s->rlayer.rbuf, sizeof(SSL3_BUFFER));
    memcpy(&(rdata->rrec), &s->rlayer.rrec, sizeof(SSL3_RECORD));

    item->data = rdata;

#ifndef OPENSSL_NO_SCTP
    /* Store bio_dgram_sctp_rcvinfo struct */
    if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
        (s->state == SSL3_ST_SR_FINISHED_A
         || s->state == SSL3_ST_CR_FINISHED_A)) {
        BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO,
                 sizeof(rdata->recordinfo), &rdata->recordinfo);
    }
#endif

    s->rlayer.packet = NULL;
    s->rlayer.packet_length = 0;
    memset(&s->rlayer.rbuf, 0, sizeof(SSL3_BUFFER));
    memset(&s->rlayer.rrec, 0, sizeof(SSL3_RECORD));

    if (!ssl3_setup_buffers(s)) {
        SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
        if (rdata->rbuf.buf != NULL)
            OPENSSL_free(rdata->rbuf.buf);
        OPENSSL_free(rdata);
        pitem_free(item);
        return (-1);
    }

    /* insert should not fail, since duplicates are dropped */
    if (pqueue_insert(queue->q, item) == NULL) {
        SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
        if (rdata->rbuf.buf != NULL)
            OPENSSL_free(rdata->rbuf.buf);
        OPENSSL_free(rdata);
        pitem_free(item);
        return (-1);
    }

    return (1);
}

int vc_create_dtls_connection(struct vContext *C)
{
	struct VC_CTX *vc_ctx = CTX_client_ctx(C);
	struct VSession *vsession = CTX_current_session(C);
	struct VDgramConn *dgram_conn = CTX_current_dgram_conn(C);
	struct timeval timeout;
	int ret = 0;

	v_print_log(VRS_PRINT_DEBUG_MSG, "Try to do DTLS handshake at UDP socket: %d\n",
			dgram_conn->io_ctx.sockfd);

	/* Create ssl for new connection */
	if( (dgram_conn->io_ctx.ssl = SSL_new(vc_ctx->dtls_ctx)) == NULL) {
		v_print_log(VRS_PRINT_ERROR, "SSL_new(%p)\n", (void*)vc_ctx->dtls_ctx);
		return 0;
	}

	/* Set state of bio as connected */
	if(dgram_conn->io_ctx.peer_addr.ip_ver == IPV4) {
		ret = BIO_ctrl(dgram_conn->io_ctx.bio, BIO_CTRL_DGRAM_SET_CONNECTED, 0, &dgram_conn->io_ctx.peer_addr.addr.ipv6);
	} else if(dgram_conn->io_ctx.peer_addr.ip_ver == IPV6) {
		ret = BIO_ctrl(dgram_conn->io_ctx.bio, BIO_CTRL_DGRAM_SET_CONNECTED, 0, &dgram_conn->io_ctx.peer_addr.addr.ipv4);
	}

	/* When BIO_ctrl was called with bad arguments, then it returns 0 */
	if(ret==0) {
		v_print_log(VRS_PRINT_ERROR, "BIO_ctrl()\n");
		SSL_free(dgram_conn->io_ctx.ssl);
		return 0;
	}

	/* Set and activate timeouts */
	timeout.tv_sec = 1;
	timeout.tv_usec = 0;
	BIO_ctrl(dgram_conn->io_ctx.bio, BIO_CTRL_DGRAM_SET_RECV_TIMEOUT, 0, &timeout);
	BIO_ctrl(dgram_conn->io_ctx.bio, BIO_CTRL_DGRAM_SET_SEND_TIMEOUT, 0, &timeout);

	/* Bind ssl and bio */
	SSL_set_bio(dgram_conn->io_ctx.ssl, dgram_conn->io_ctx.bio, dgram_conn->io_ctx.bio);

	/* Try to do DTLS handshake */
again:
	if ((ret = SSL_connect(dgram_conn->io_ctx.ssl)) <= 0) {
		int err = SSL_get_error(dgram_conn->io_ctx.ssl, ret);
		if(err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE) {
			gettimeofday(&timeout, NULL);
			if((timeout.tv_sec - vsession->peer_token.tv.tv_sec) > VRS_TIMEOUT) {
				v_print_log(VRS_PRINT_ERROR, "Token timed out\n");
				return 0;
			}
			usleep(1000);
			goto again;
		}
		ERR_print_errors_fp(stderr);
		v_print_log(VRS_PRINT_ERROR, "SSL_connect() failed: %d -> %d\n", ret, err);
		SSL_free(dgram_conn->io_ctx.ssl);
		dgram_conn->io_ctx.ssl = NULL;
		dgram_conn->io_ctx.bio = NULL;
		return 0;
	} else {
		v_print_log(VRS_PRINT_DEBUG_MSG, "DTLS handshake finished\n");

		v_print_log(VRS_PRINT_DEBUG_MSG, "Current cipher: %s\n",
				SSL_CIPHER_get_name(SSL_get_current_cipher(dgram_conn->io_ctx.ssl)));
	}

	return 1;
}

long BIO_get_mem_data(BIO *bio, char **contents) {
  return BIO_ctrl(bio, BIO_CTRL_INFO, 0, (char *) contents);
}

static long enc_ctrl(BIO *b, int cmd, long num, void *ptr)
  {
  BIO *dbio;
  BIO_ENC_CTX *ctx,*dctx;
  long ret=1;
  int i;
  EVP_CIPHER_CTX **c_ctx;

  ctx=(BIO_ENC_CTX *)b->ptr;

  switch (cmd)
    {
  case BIO_CTRL_RESET:
    ctx->ok=1;
    ctx->finished=0;
    EVP_CipherInit_ex(&(ctx->cipher),NULL,NULL,NULL,NULL,
      ctx->cipher.encrypt);
    ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
    break;
  case BIO_CTRL_EOF:  /* More to read */
    if (ctx->cont <= 0)
      ret=1;
    else
      ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
    break;
  case BIO_CTRL_WPENDING:
    ret=ctx->buf_len-ctx->buf_off;
    if (ret <= 0)
      ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
    break;
  case BIO_CTRL_PENDING: /* More to read in buffer */
    ret=ctx->buf_len-ctx->buf_off;
    if (ret <= 0)
      ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
    break;
  case BIO_CTRL_FLUSH:
    /* do a final write */
again:
    while (ctx->buf_len != ctx->buf_off)
      {
      i=enc_write(b,NULL,0);
      if (i < 0)
        return i;
      }

    if (!ctx->finished)
      {
      ctx->finished=1;
      ctx->buf_off=0;
      ret=EVP_CipherFinal_ex(&(ctx->cipher),
        (unsigned char *)ctx->buf,
        &(ctx->buf_len));
      ctx->ok=(int)ret;
      if (ret <= 0) break;

      /* push out the bytes */
      goto again;
      }
    
    /* Finally flush the underlying BIO */
    ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
    break;
  case BIO_C_GET_CIPHER_STATUS:
    ret=(long)ctx->ok;
    break;
  case BIO_C_DO_STATE_MACHINE:
    BIO_clear_retry_flags(b);
    ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
    BIO_copy_next_retry(b);
    break;
  case BIO_C_GET_CIPHER_CTX:
    c_ctx=(EVP_CIPHER_CTX **)ptr;
    (*c_ctx)= &(ctx->cipher);
    b->init=1;
    break;
  case BIO_CTRL_DUP:
    dbio=(BIO *)ptr;
    dctx=(BIO_ENC_CTX *)dbio->ptr;
    memcpy(&(dctx->cipher),&(ctx->cipher),sizeof(ctx->cipher));
    dbio->init=1;
    break;
  default:
    ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
    break;
    }
  return(ret);
  }

size_t BIO_ctrl_wpending(BIO *bio)
	{
	return BIO_ctrl(bio, BIO_CTRL_WPENDING, 0, NULL);
	}

static long md_ctrl(BIO *b, int cmd, long num, void *ptr)
{
    EVP_MD_CTX *ctx, *dctx, **pctx;
    const EVP_MD **ppmd;
    EVP_MD *md;
    long ret = 1;
    BIO *dbio, *next;


    ctx = BIO_get_data(b);
    next = BIO_next(b);

    switch (cmd) {
    case BIO_CTRL_RESET:
        if (BIO_get_init(b))
            ret = EVP_DigestInit_ex(ctx, ctx->digest, NULL);
        else
            ret = 0;
        if (ret > 0)
            ret = BIO_ctrl(next, cmd, num, ptr);
        break;
    case BIO_C_GET_MD:
        if (BIO_get_init(b)) {
            ppmd = ptr;
            *ppmd = ctx->digest;
        } else
            ret = 0;
        break;
    case BIO_C_GET_MD_CTX:
        pctx = ptr;
        *pctx = ctx;
        BIO_set_init(b, 1);
        break;
    case BIO_C_SET_MD_CTX:
        if (BIO_get_init(b))
            BIO_set_data(b, ptr);
        else
            ret = 0;
        break;
    case BIO_C_DO_STATE_MACHINE:
        BIO_clear_retry_flags(b);
        ret = BIO_ctrl(next, cmd, num, ptr);
        BIO_copy_next_retry(b);
        break;

    case BIO_C_SET_MD:
        md = ptr;
        ret = EVP_DigestInit_ex(ctx, md, NULL);
        if (ret > 0)
            BIO_set_init(b, 1);
        break;
    case BIO_CTRL_DUP:
        dbio = ptr;
        dctx = BIO_get_data(dbio);
        if (!EVP_MD_CTX_copy_ex(dctx, ctx))
            return 0;
        BIO_set_init(b, 1);
        break;
    default:
        ret = BIO_ctrl(next, cmd, num, ptr);
        break;
    }
    return ret;
}

/*-
 * Return up to 'len' payload bytes received in 'type' records.
 * 'type' is one of the following:
 *
 *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 *   -  0 (during a shutdown, no data has to be returned)
 *
 * If we don't have stored data to work from, read a SSL/TLS record first
 * (possibly multiple records if we still don't have anything to return).
 *
 * This function must handle any surprises the peer may have for us, such as
 * Alert records (e.g. close_notify) or renegotiation requests. ChangeCipherSpec
 * messages are treated as if they were handshake messages *if* the |recd_type|
 * argument is non NULL.
 * Also if record payloads contain fragments too small to process, we store
 * them until there is enough for the respective protocol (the record protocol
 * may use arbitrary fragmentation and even interleaving):
 *     Change cipher spec protocol
 *             just 1 byte needed, no need for keeping anything stored
 *     Alert protocol
 *             2 bytes needed (AlertLevel, AlertDescription)
 *     Handshake protocol
 *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 *             to detect unexpected Client Hello and Hello Request messages
 *             here, anything else is handled by higher layers
 *     Application data protocol
 *             none of our business
 */
int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
                     int len, int peek)
{
    int al, i, j, ret;
    unsigned int n;
    SSL3_RECORD *rr;
    void (*cb) (const SSL *ssl, int type2, int val) = NULL;

    if (!SSL3_BUFFER_is_initialised(&s->rlayer.rbuf)) {
        /* Not initialized yet */
        if (!ssl3_setup_buffers(s))
            return (-1);
    }

    if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
         (type != SSL3_RT_HANDSHAKE)) ||
        (peek && (type != SSL3_RT_APPLICATION_DATA))) {
        SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
        return -1;
    }

    /*
     * check whether there's a handshake message (client hello?) waiting
     */
    if ((ret = have_handshake_fragment(s, type, buf, len))) {
        *recvd_type = SSL3_RT_HANDSHAKE;
        return ret;
    }

    /*
     * Now s->rlayer.d->handshake_fragment_len == 0 if
     * type == SSL3_RT_HANDSHAKE.
     */

    if (!ossl_statem_get_in_handshake(s) && SSL_in_init(s))
    {
        /* type == SSL3_RT_APPLICATION_DATA */
        i = s->handshake_func(s);
        if (i < 0)
            return (i);
        if (i == 0) {
            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
            return (-1);
        }
    }

 start:
    s->rwstate = SSL_NOTHING;

    /*-
     * s->s3->rrec.type         - is the type of record
     * s->s3->rrec.data,    - data
     * s->s3->rrec.off,     - offset into 'data' for next read
     * s->s3->rrec.length,  - number of bytes.
     */
    rr = s->rlayer.rrec;

    /*
     * We are not handshaking and have no data yet, so process data buffered
     * during the last handshake in advance, if any.
     */
    if (SSL_is_init_finished(s) && SSL3_RECORD_get_length(rr) == 0) {
        pitem *item;
        item = pqueue_pop(s->rlayer.d->buffered_app_data.q);
        if (item) {
#ifndef OPENSSL_NO_SCTP
            /* Restore bio_dgram_sctp_rcvinfo struct */
            if (BIO_dgram_is_sctp(SSL_get_rbio(s))) {
                DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data;
                BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO,
                         sizeof(rdata->recordinfo), &rdata->recordinfo);
//.........这里部分代码省略.........

MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt)
{
    int al;
    long remain;

    remain = PACKET_remaining(pkt);
    /*
     * 'Change Cipher Spec' is just a single byte, which should already have
     * been consumed by ssl_get_message() so there should be no bytes left,
     * unless we're using DTLS1_BAD_VER, which has an extra 2 bytes
     */
    if (SSL_IS_DTLS(s)) {
        if ((s->version == DTLS1_BAD_VER
                        && remain != DTLS1_CCS_HEADER_LENGTH + 1)
                    || (s->version != DTLS1_BAD_VER
                        && remain != DTLS1_CCS_HEADER_LENGTH - 1)) {
                al = SSL_AD_ILLEGAL_PARAMETER;
                SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
                       SSL_R_BAD_CHANGE_CIPHER_SPEC);
                goto f_err;
        }
    } else {
        if (remain != 0) {
            al = SSL_AD_ILLEGAL_PARAMETER;
            SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
                   SSL_R_BAD_CHANGE_CIPHER_SPEC);
            goto f_err;
        }
    }

    /* Check we have a cipher to change to */
    if (s->s3->tmp.new_cipher == NULL) {
        al = SSL_AD_UNEXPECTED_MESSAGE;
        SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, SSL_R_CCS_RECEIVED_EARLY);
        goto f_err;
    }

    s->s3->change_cipher_spec = 1;
    if (!ssl3_do_change_cipher_spec(s)) {
        al = SSL_AD_INTERNAL_ERROR;
        SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
        goto f_err;
    }

    if (SSL_IS_DTLS(s)) {
        dtls1_reset_seq_numbers(s, SSL3_CC_READ);

        if (s->version == DTLS1_BAD_VER)
            s->d1->handshake_read_seq++;

#ifndef OPENSSL_NO_SCTP
        /*
         * Remember that a CCS has been received, so that an old key of
         * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
         * SCTP is used
         */
        BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
#endif
    }

    return MSG_PROCESS_CONTINUE_READING;
 f_err:
    ssl3_send_alert(s, SSL3_AL_FATAL, al);
    ossl_statem_set_error(s);
    return MSG_PROCESS_ERROR;
}

int dtls1_accept(SSL *s)
	{
	BUF_MEM *buf;
	unsigned long Time=(unsigned long)time(NULL);
	void (*cb)(const SSL *ssl,int type,int val)=NULL;
	unsigned long alg_k;
	int ret= -1;
	int new_state,state,skip=0;
	int listen;
#ifndef OPENSSL_NO_SCTP
	unsigned char sctpauthkey[64];
	char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
#endif

	RAND_add(&Time,sizeof(Time),0);
	ERR_clear_error();
	clear_sys_error();

	if (s->info_callback != NULL)
		cb=s->info_callback;
	else if (s->ctx->info_callback != NULL)
		cb=s->ctx->info_callback;
	
	listen = s->d1->listen;

	/* init things to blank */
	s->in_handshake++;
	if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);

	s->d1->listen = listen;
#ifndef OPENSSL_NO_SCTP
	/* Notify SCTP BIO socket to enter handshake
	 * mode and prevent stream identifier other
	 * than 0. Will be ignored if no SCTP is used.
	 */
	BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE, s->in_handshake, NULL);
#endif

	if (s->cert == NULL)
		{
		SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
		return(-1);
		}

#ifndef OPENSSL_NO_HEARTBEATS
	/* If we're awaiting a HeartbeatResponse, pretend we
	 * already got and don't await it anymore, because
	 * Heartbeats don't make sense during handshakes anyway.
	 */
	if (s->tlsext_hb_pending)
		{
		dtls1_stop_timer(s);
		s->tlsext_hb_pending = 0;
		s->tlsext_hb_seq++;
		}
#endif

	for (;;)
		{
		state=s->state;

		switch (s->state)
			{
		case SSL_ST_RENEGOTIATE:
			s->renegotiate=1;
			/* s->state=SSL_ST_ACCEPT; */

		case SSL_ST_BEFORE:
		case SSL_ST_ACCEPT:
		case SSL_ST_BEFORE|SSL_ST_ACCEPT:
		case SSL_ST_OK|SSL_ST_ACCEPT:

			s->server=1;
			if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);

			if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
				{
				SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
				return -1;
				}
			s->type=SSL_ST_ACCEPT;

			if (s->init_buf == NULL)
				{
				if ((buf=BUF_MEM_new()) == NULL)
					{
					ret= -1;
					goto end;
					}
				if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
					{
					ret= -1;
					goto end;
					}
				s->init_buf=buf;
				}

			if (!ssl3_setup_buffers(s))
				{
				ret= -1;
//.........这里部分代码省略.........

int eHttpStream::openUrl(const std::string &url, std::string &newurl)
{
	int port;
	std::string hostname;
	std::string uri = url;
	std::string request;
	size_t buflen = 1024;
	char *linebuf = NULL;
	int result;
	char proto[100];
	int statuscode = 0;
	char statusmsg[100];
	bool playlist = false;
	bool contenttypeparsed = false;

	close();

	std::string user_agent = "Enigma2 HbbTV/1.1.1 (+PVR+RTSP+DL;openNFR;;;)";
	std::string extra_headers = "";
	size_t pos = uri.find('#');
	if (pos != std::string::npos)
	{
		extra_headers = uri.substr(pos + 1);
		uri = uri.substr(0, pos);

		pos = extra_headers.find("User-Agent=");
		if (pos != std::string::npos)
		{
			size_t hpos_start = pos + 11;
			size_t hpos_end = extra_headers.find('&', hpos_start);
			if (hpos_end != std::string::npos)
				user_agent = extra_headers.substr(hpos_start, hpos_end - hpos_start);
			else
				user_agent = extra_headers.substr(hpos_start);
		}
	}

	int pathindex = uri.find("/", 7);
	if (pathindex > 0)
	{
		hostname = uri.substr(7, pathindex - 7);
		uri = uri.substr(pathindex, uri.length() - pathindex);
	}
	else
	{
		hostname = uri.substr(7, uri.length() - 7);
		uri = "/";
	}
	int authenticationindex = hostname.find("@");
	if (authenticationindex > 0)
	{
		BIO *mbio, *b64bio, *bio;
		char *p = (char*)NULL;
		int length = 0;
		authorizationData = hostname.substr(0, authenticationindex);
		hostname = hostname.substr(authenticationindex + 1);
		mbio = BIO_new(BIO_s_mem());
		b64bio = BIO_new(BIO_f_base64());
		bio = BIO_push(b64bio, mbio);
		BIO_write(bio, authorizationData.c_str(), authorizationData.length());
		BIO_flush(bio);
		length = BIO_ctrl(mbio, BIO_CTRL_INFO, 0, (char*)&p);
		authorizationData = "";
		if (p && length > 0)
		{
			/* base64 output contains a linefeed, which we ignore */
			authorizationData.append(p, length - 1);
		}
		BIO_free_all(bio);
	}
	int customportindex = hostname.find(":");
	if (customportindex > 0)
	{
		port = atoi(hostname.substr(customportindex + 1, hostname.length() - customportindex - 1).c_str());
		hostname = hostname.substr(0, customportindex);
	}
	else if (customportindex == 0)
	{
		port = atoi(hostname.substr(1, hostname.length() - 1).c_str());
		hostname = "localhost";
	}
	else
	{
		port = 80;
	}

	streamSocket = Connect(hostname.c_str(), port, 10);
	if (streamSocket < 0)
		goto error;

	request = "GET ";
	request.append(uri).append(" HTTP/1.1\r\n");
	request.append("Host: ").append(hostname).append("\r\n");
	request.append("User-Agent: ").append(user_agent).append("\r\n");
	if (authorizationData != "")
	{
		request.append("Authorization: Basic ").append(authorizationData).append("\r\n");
	}

	pos = 0;
//.........这里部分代码省略.........

static long asn1_bio_ctrl(BIO *b, int cmd, long arg1, void *arg2)
{
    BIO_ASN1_BUF_CTX *ctx;
    BIO_ASN1_EX_FUNCS *ex_func;
    long ret = 1;
    BIO *next;

    ctx = BIO_get_data(b);
    if (ctx == NULL)
        return 0;
    next = BIO_next(b);
    switch (cmd) {

    case BIO_C_SET_PREFIX:
        ex_func = arg2;
        ctx->prefix = ex_func->ex_func;
        ctx->prefix_free = ex_func->ex_free_func;
        break;

    case BIO_C_GET_PREFIX:
        ex_func = arg2;
        ex_func->ex_func = ctx->prefix;
        ex_func->ex_free_func = ctx->prefix_free;
        break;

    case BIO_C_SET_SUFFIX:
        ex_func = arg2;
        ctx->suffix = ex_func->ex_func;
        ctx->suffix_free = ex_func->ex_free_func;
        break;

    case BIO_C_GET_SUFFIX:
        ex_func = arg2;
        ex_func->ex_func = ctx->suffix;
        ex_func->ex_free_func = ctx->suffix_free;
        break;

    case BIO_C_SET_EX_ARG:
        ctx->ex_arg = arg2;
        break;

    case BIO_C_GET_EX_ARG:
        *(void **)arg2 = ctx->ex_arg;
        break;

    case BIO_CTRL_FLUSH:
        if (next == NULL)
            return 0;

        /* Call post function if possible */
        if (ctx->state == ASN1_STATE_HEADER) {
            if (!asn1_bio_setup_ex(b, ctx, ctx->suffix,
                                   ASN1_STATE_POST_COPY, ASN1_STATE_DONE))
                return 0;
        }

        if (ctx->state == ASN1_STATE_POST_COPY) {
            ret = asn1_bio_flush_ex(b, ctx, ctx->suffix_free,
                                    ASN1_STATE_DONE);
            if (ret <= 0)
                return ret;
        }

        if (ctx->state == ASN1_STATE_DONE)
            return BIO_ctrl(next, cmd, arg1, arg2);
        else {
            BIO_clear_retry_flags(b);
            return 0;
        }

    default:
        if (next == NULL)
            return 0;
        return BIO_ctrl(next, cmd, arg1, arg2);

    }

    return ret;
}

//.........这里部分代码省略.........
		{
		BIO_printf(bio_err,"connect:errno=%d\n",get_last_socket_error());
		SHUTDOWN(s);
		goto end;
		}
	BIO_printf(bio_c_out,"CONNECTED(%08X)\n",s);

#ifdef FIONBIO
	if (c_nbio)
		{
		unsigned long l=1;
		BIO_printf(bio_c_out,"turning on non blocking io\n");
		if (BIO_socket_ioctl(s,FIONBIO,&l) < 0)
			{
			ERR_print_errors(bio_err);
			goto end;
			}
		}
#endif                                              
	if (c_Pause & 0x01) con->debug=1;

	if ( SSL_version(con) == DTLS1_VERSION)
		{

		sbio=BIO_new_dgram(s,BIO_NOCLOSE);
		if (getsockname(s, &peer, (void *)&peerlen) < 0)
			{
			BIO_printf(bio_err, "getsockname:errno=%d\n",
				get_last_socket_error());
			SHUTDOWN(s);
			goto end;
			}

		(void)BIO_ctrl_set_connected(sbio, 1, &peer);

		if ( enable_timeouts)
			{
			timeout.tv_sec = 0;
			timeout.tv_usec = DGRAM_RCV_TIMEOUT;
			BIO_ctrl(sbio, BIO_CTRL_DGRAM_SET_RECV_TIMEOUT, 0, &timeout);
			
			timeout.tv_sec = 0;
			timeout.tv_usec = DGRAM_SND_TIMEOUT;
			BIO_ctrl(sbio, BIO_CTRL_DGRAM_SET_SEND_TIMEOUT, 0, &timeout);
			}

		if (socket_mtu > 28)
			{
			SSL_set_options(con, SSL_OP_NO_QUERY_MTU);
			SSL_set_mtu(con, socket_mtu - 28);
			}
		else
			/* want to do MTU discovery */
			BIO_ctrl(sbio, BIO_CTRL_DGRAM_MTU_DISCOVER, 0, NULL);
		}
	else
		sbio=BIO_new_socket(s,BIO_NOCLOSE);

	if (nbio_test)
		{
		BIO *test;

		test=BIO_new(BIO_f_nbio_test());
		sbio=BIO_push(test,sbio);
		}

static long
linebuffer_ctrl(BIO *b, int cmd, long num, void *ptr)
{
	BIO *dbio;
	BIO_LINEBUFFER_CTX *ctx;
	long ret = 1;
	char *p;
	int r;
	int obs;

	ctx = (BIO_LINEBUFFER_CTX *)b->ptr;

	switch (cmd) {
	case BIO_CTRL_RESET:
		ctx->obuf_len = 0;
		if (b->next_bio == NULL)
			return (0);
		ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
		break;
	case BIO_CTRL_INFO:
		ret = (long)ctx->obuf_len;
		break;
	case BIO_CTRL_WPENDING:
		ret = (long)ctx->obuf_len;
		if (ret == 0) {
			if (b->next_bio == NULL)
				return (0);
			ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
		}
		break;
	case BIO_C_SET_BUFF_SIZE:
		obs = (int)num;
		p = ctx->obuf;
		if ((obs > DEFAULT_LINEBUFFER_SIZE) && (obs != ctx->obuf_size)) {
			p = malloc(num);
			if (p == NULL)
				goto malloc_error;
		}
		if (ctx->obuf != p) {
			if (ctx->obuf_len > obs) {
				ctx->obuf_len = obs;
			}
			memcpy(p, ctx->obuf, ctx->obuf_len);
			free(ctx->obuf);
			ctx->obuf = p;
			ctx->obuf_size = obs;
		}
		break;
	case BIO_C_DO_STATE_MACHINE:
		if (b->next_bio == NULL)
			return (0);
		BIO_clear_retry_flags(b);
		ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
		BIO_copy_next_retry(b);
		break;

	case BIO_CTRL_FLUSH:
		if (b->next_bio == NULL)
			return (0);
		if (ctx->obuf_len <= 0) {
			ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
			break;
		}

		for (;;) {
			BIO_clear_retry_flags(b);
			if (ctx->obuf_len > 0) {
				r = BIO_write(b->next_bio,
				    ctx->obuf, ctx->obuf_len);
				BIO_copy_next_retry(b);
				if (r <= 0)
					return ((long)r);
				if (r < ctx->obuf_len)
					memmove(ctx->obuf, ctx->obuf + r,
					    ctx->obuf_len - r);
				ctx->obuf_len -= r;
			} else {
				ctx->obuf_len = 0;
				ret = 1;
				break;
			}
		}
		ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
		break;
	case BIO_CTRL_DUP:
		dbio = (BIO *)ptr;
		if (!BIO_set_write_buffer_size(dbio, ctx->obuf_size))
			ret = 0;
		break;
	default:
		if (b->next_bio == NULL)
			return (0);
		ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
		break;
	}
	return (ret);
malloc_error:
	BIOerror(ERR_R_MALLOC_FAILURE);
	return (0);
}

/* send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or SSL3_RT_CHANGE_CIPHER_SPEC) */
int dtls1_do_write(SSL *s, int type)
	{
	int ret;
	int curr_mtu;
	unsigned int len, frag_off;

	/* AHA!  Figure out the MTU, and stick to the right size */
	if ( ! (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU))
		{
		s->d1->mtu = 
			BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);

		/* I've seen the kernel return bogus numbers when it doesn't know
		 * (initial write), so just make sure we have a reasonable number */
		if ( s->d1->mtu < dtls1_min_mtu())
			{
			s->d1->mtu = 0;
			s->d1->mtu = dtls1_guess_mtu(s->d1->mtu);
			BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU, 
				s->d1->mtu, NULL);
			}
		}
#if 0 
	mtu = s->d1->mtu;

	fprintf(stderr, "using MTU = %d\n", mtu);

	mtu -= (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH);

	curr_mtu = mtu - BIO_wpending(SSL_get_wbio(s));

	if ( curr_mtu > 0)
		mtu = curr_mtu;
	else if ( ( ret = BIO_flush(SSL_get_wbio(s))) <= 0)
		return ret;

	if ( BIO_wpending(SSL_get_wbio(s)) + s->init_num >= mtu)
		{
		ret = BIO_flush(SSL_get_wbio(s));
		if ( ret <= 0)
			return ret;
		mtu = s->d1->mtu - (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH);
		}

	OPENSSL_assert(mtu > 0);  /* should have something reasonable now */

#endif

	if ( s->init_off == 0  && type == SSL3_RT_HANDSHAKE)
		OPENSSL_assert(s->init_num == 
			(int)s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH);

	frag_off = 0;
	while( s->init_num)
		{
		curr_mtu = s->d1->mtu - BIO_wpending(SSL_get_wbio(s)) - 
			DTLS1_RT_HEADER_LENGTH;

		if ( curr_mtu <= DTLS1_HM_HEADER_LENGTH)
			{
			/* grr.. we could get an error if MTU picked was wrong */
			ret = BIO_flush(SSL_get_wbio(s));
			if ( ret <= 0)
				return ret;
			curr_mtu = s->d1->mtu - DTLS1_RT_HEADER_LENGTH;
			}

		if ( s->init_num > curr_mtu)
			len = curr_mtu;
		else
			len = s->init_num;


		/* XDTLS: this function is too long.  split out the CCS part */
		if ( type == SSL3_RT_HANDSHAKE)
			{
			if ( s->init_off != 0)
				{
				OPENSSL_assert(s->init_off > DTLS1_HM_HEADER_LENGTH);
				s->init_off -= DTLS1_HM_HEADER_LENGTH;
				s->init_num += DTLS1_HM_HEADER_LENGTH;

				/* write atleast DTLS1_HM_HEADER_LENGTH bytes */
				if ( len <= DTLS1_HM_HEADER_LENGTH)  
					len += DTLS1_HM_HEADER_LENGTH;
				}

			dtls1_fix_message_header(s, frag_off, 
				len - DTLS1_HM_HEADER_LENGTH);

			dtls1_write_message_header(s, (unsigned char *)&s->init_buf->data[s->init_off]);

			OPENSSL_assert(len >= DTLS1_HM_HEADER_LENGTH);
			}

		ret=dtls1_write_bytes(s,type,&s->init_buf->data[s->init_off],
			len);
		if (ret < 0)
			{
//.........这里部分代码省略.........

static long bio_zlib_ctrl(BIO *b, int cmd, long num, void *ptr)
{
    BIO_ZLIB_CTX *ctx;
    int ret, *ip;
    int ibs, obs;
    BIO *next = BIO_next(b);

    if (next == NULL)
        return 0;
    ctx = BIO_get_data(b);
    switch (cmd) {

    case BIO_CTRL_RESET:
        ctx->ocount = 0;
        ctx->odone = 0;
        ret = 1;
        break;

    case BIO_CTRL_FLUSH:
        ret = bio_zlib_flush(b);
        if (ret > 0)
            ret = BIO_flush(next);
        break;

    case BIO_C_SET_BUFF_SIZE:
        ibs = -1;
        obs = -1;
        if (ptr != NULL) {
            ip = ptr;
            if (*ip == 0)
                ibs = (int)num;
            else
                obs = (int)num;
        } else {
            ibs = (int)num;
            obs = ibs;
        }

        if (ibs != -1) {
            OPENSSL_free(ctx->ibuf);
            ctx->ibuf = NULL;
            ctx->ibufsize = ibs;
        }

        if (obs != -1) {
            OPENSSL_free(ctx->obuf);
            ctx->obuf = NULL;
            ctx->obufsize = obs;
        }
        ret = 1;
        break;

    case BIO_C_DO_STATE_MACHINE:
        BIO_clear_retry_flags(b);
        ret = BIO_ctrl(next, cmd, num, ptr);
        BIO_copy_next_retry(b);
        break;

    default:
        ret = BIO_ctrl(next, cmd, num, ptr);
        break;

    }

    return ret;
}