utility.c

经典的unix下telnetd代码

    if (length < 1) {
	output_data("(Empty suboption??\?)");
	return;
    }
    switch (pointer[0]) {
    case TELOPT_TTYPE:
	output_data("TERMINAL-TYPE ");
	switch (pointer[1]) {
	case TELQUAL_IS:
	    output_data("IS \"%.*s\"",
			length-2,
			(char *)pointer+2);
	    break;
	case TELQUAL_SEND:
	    output_data("SEND");
	    break;
	default:
	    output_data("- unknown qualifier %d (0x%x).",
			pointer[1], pointer[1]);
	}
	break;
    case TELOPT_TSPEED:
	output_data("TERMINAL-SPEED");
	if (length < 2) {
	    output_data(" (empty suboption??\?)");
	    break;
	}
	switch (pointer[1]) {
	case TELQUAL_IS:
	    output_data(" IS %.*s", length-2, (char *)pointer+2);
	    break;
	default:
	    if (pointer[1] == 1)
		output_data(" SEND");
	    else
		output_data(" %d (unknown)", pointer[1]);
	    for (i = 2; i < length; i++) {
		output_data(" ?%d?", pointer[i]);
	    }
	    break;
	}
	break;

    case TELOPT_LFLOW:
	output_data("TOGGLE-FLOW-CONTROL");
	if (length < 2) {
	    output_data(" (empty suboption??\?)");
	    break;
	}
	switch (pointer[1]) {
	case LFLOW_OFF:
	    output_data(" OFF");
	    break;
	case LFLOW_ON:
	    output_data(" ON");
	    break;
	case LFLOW_RESTART_ANY:
	    output_data(" RESTART-ANY");
	    break;
	case LFLOW_RESTART_XON:
	    output_data(" RESTART-XON");
	    break;
	default:
	    output_data(" %d (unknown)",
			pointer[1]);
	}
	for (i = 2; i < length; i++) {
	    output_data(" ?%d?",
			pointer[i]);
	}
	break;

    case TELOPT_NAWS:
	output_data("NAWS");
	if (length < 2) {
	    output_data(" (empty suboption??\?)");
	    break;
	}
	if (length == 2) {
	    output_data(" ?%d?",
			pointer[1]);
	    break;
	}
	output_data(" %u %u(%u)",
		    pointer[1],
		    pointer[2],
		    (((unsigned int)pointer[1])<<8) + pointer[2]);
	if (length == 4) {
	    output_data(" ?%d?",
			pointer[3]);
	    break;
	}
	output_data(" %u %u(%u)",
		    pointer[3],
		    pointer[4],
		    (((unsigned int)pointer[3])<<8) + pointer[4]);
	for (i = 5; i < length; i++) {
	    output_data(" ?%d?",
			pointer[i]);
	}
	break;

    case TELOPT_LINEMODE:
	output_data("LINEMODE ");
	if (length < 2) {
	    output_data(" (empty suboption??\?)");
	    break;
	}
	switch (pointer[1]) {
	case WILL:
	    output_data("WILL ");
	    goto common;
	case WONT:
	    output_data("WONT ");
	    goto common;
	case DO:
	    output_data("DO ");
	    goto common;
	case DONT:
	    output_data("DONT ");
	common:
	    if (length < 3) {
		output_data("(no option??\?)");
		break;
	    }
	    switch (pointer[2]) {
	    case LM_FORWARDMASK:
		output_data("Forward Mask");
		for (i = 3; i < length; i++) {
		    output_data(" %x", pointer[i]);
		}
		break;
	    default:
		output_data("%d (unknown)",
			    pointer[2]);
		for (i = 3; i < length; i++) {
		    output_data(" %d",
				pointer[i]);
		}
		break;
	    }
	    break;

	case LM_SLC:
	    output_data("SLC");
	    for (i = 2; i < length - 2; i += 3) {
		if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
		    output_data(" %s",
				SLC_NAME(pointer[i+SLC_FUNC]));
		else
		    output_data(" %d",
				pointer[i+SLC_FUNC]);
		switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
		case SLC_NOSUPPORT:
		    output_data(" NOSUPPORT");
		    break;
		case SLC_CANTCHANGE:
		    output_data(" CANTCHANGE");
		    break;
		case SLC_VARIABLE:
		    output_data(" VARIABLE");
		    break;
		case SLC_DEFAULT:
		    output_data(" DEFAULT");
		    break;
		}
		output_data("%s%s%s",
			    pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
			    pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
			    pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
		if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
					    SLC_FLUSHOUT| SLC_LEVELBITS)) {
		    output_data("(0x%x)",
				pointer[i+SLC_FLAGS]);
		}
		output_data(" %d;",
			    pointer[i+SLC_VALUE]);
		if ((pointer[i+SLC_VALUE] == IAC) &&
		    (pointer[i+SLC_VALUE+1] == IAC))
		    i++;
	    }
	    for (; i < length; i++) {
		output_data(" ?%d?",
			    pointer[i]);
	    }
	    break;

	case LM_MODE:
	    output_data("MODE ");
	    if (length < 3) {
		output_data("(no mode??\?)");
		break;
	    }
	    {
		char tbuf[32];
		snprintf(tbuf,
			 sizeof(tbuf),
			 "%s%s%s%s%s",
			 pointer[2]&MODE_EDIT ? "|EDIT" : "",
			 pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
			 pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
			 pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
			 pointer[2]&MODE_ACK ? "|ACK" : "");
		output_data("%s",
			    tbuf[1] ? &tbuf[1] : "0");
	    }
	    if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK)) {
		output_data(" (0x%x)",
			    pointer[2]);
	    }
	    for (i = 3; i < length; i++) {
		output_data(" ?0x%x?",
			 pointer[i]);
	    }
	    break;
	default:
	    output_data("%d (unknown)",
			pointer[1]);
	    for (i = 2; i < length; i++) {
		output_data(" %d", pointer[i]);
	    }
	}
	break;

    case TELOPT_STATUS: {
	char *cp;
	int j, k;

	output_data("STATUS");

	switch (pointer[1]) {
	default:
	    if (pointer[1] == TELQUAL_SEND)
		output_data(" SEND");
	    else
		output_data(" %d (unknown)",
			    pointer[1]);
	    for (i = 2; i < length; i++) {
		output_data(" ?%d?",
			    pointer[i]);
	    }
	    break;
	case TELQUAL_IS:
	    output_data(" IS\r\n");

	    for (i = 2; i < length; i++) {
		switch(pointer[i]) {
		case DO:	cp = "DO"; goto common2;
		case DONT:	cp = "DONT"; goto common2;
		case WILL:	cp = "WILL"; goto common2;
		case WONT:	cp = "WONT"; goto common2;
		common2:
		i++;
		if (TELOPT_OK(pointer[i]))
		    output_data(" %s %s",
				cp,
				TELOPT(pointer[i]));
		else
		    output_data(" %s %d",
				cp,
				pointer[i]);

		output_data("\r\n");
		break;

		case SB:
		    output_data(" SB ");
		    i++;
		    j = k = i;
		    while (j < length) {
			if (pointer[j] == SE) {
			    if (j+1 == length)
				break;
			    if (pointer[j+1] == SE)
				j++;
			    else
				break;
			}
			pointer[k++] = pointer[j++];
		    }
		    printsub(0, &pointer[i], k - i);
		    if (i < length) {
			output_data(" SE");
			i = j;
		    } else
			i = j - 1;

		    output_data("\r\n");

		    break;

		default:
		    output_data(" %d",
				pointer[i]);
		    break;
		}
	    }
	    break;
	}
	break;
    }

    case TELOPT_XDISPLOC:
	output_data("X-DISPLAY-LOCATION ");
	switch (pointer[1]) {
	case TELQUAL_IS:
	    output_data("IS \"%.*s\"",
			length-2,
			(char *)pointer+2);
	    break;
	case TELQUAL_SEND:
	    output_data("SEND");
	    break;
	default:
	    output_data("- unknown qualifier %d (0x%x).",
			pointer[1], pointer[1]);
	}
	break;

    case TELOPT_NEW_ENVIRON:
	output_data("NEW-ENVIRON ");
	goto env_common1;
    case TELOPT_OLD_ENVIRON:
	output_data("OLD-ENVIRON");
    env_common1:
	switch (pointer[1]) {
	case TELQUAL_IS:
	    output_data("IS ");
	    goto env_common;
	case TELQUAL_SEND:
	    output_data("SEND ");
	    goto env_common;
	case TELQUAL_INFO:
	    output_data("INFO ");
	env_common:
	    {
		int noquote = 2;
		for (i = 2; i < length; i++ ) {
		    switch (pointer[i]) {
		    case NEW_ENV_VAR:
			output_data("\" VAR " + noquote);
			noquote = 2;
			break;

		    case NEW_ENV_VALUE:
			output_data("\" VALUE " + noquote);
			noquote = 2;
			break;

		    case ENV_ESC:
			output_data("\" ESC " + noquote);
			noquote = 2;
			break;

		    case ENV_USERVAR:
			output_data("\" USERVAR " + noquote);
			noquote = 2;
			break;

		    default:
			if (isprint(pointer[i]) && pointer[i] != '"') {
			    if (noquote) {
				output_data ("\"");
				noquote = 0;
			    }
			    output_data ("%c", pointer[i]);
			} else {
			    output_data("\" %03o " + noquote,
					pointer[i]);
			    noquote = 2;
			}
			break;
		    }
		}
		if (!noquote)
		    output_data ("\"");
		break;
	    }
	}
	break;

#ifdef AUTHENTICATION
    case TELOPT_AUTHENTICATION:
	output_data("AUTHENTICATION");

	if (length < 2) {
	    output_data(" (empty suboption??\?)");
	    break;
	}
	switch (pointer[1]) {
	case TELQUAL_REPLY:
	case TELQUAL_IS:
	    output_data(" %s ",
			(pointer[1] == TELQUAL_IS) ?
			"IS" : "REPLY");
	    if (AUTHTYPE_NAME_OK(pointer[2]))
		output_data("%s ",
			    AUTHTYPE_NAME(pointer[2]));
	    else
		output_data("%d ",
			    pointer[2]);
	    if (length < 3) {
		output_data("(partial suboption??\?)");
		break;
	    }
	    output_data("%s|%s",
			((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
			"CLIENT" : "SERVER",
			((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
			"MUTUAL" : "ONE-WAY");

	    auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
	    output_data("%s",
			buf);
	    break;

	case TELQUAL_SEND:
	    i = 2;
	    output_data(" SEND ");
	    while (i < length) {
		if (AUTHTYPE_NAME_OK(pointer[i]))
		    output_data("%s ",
				AUTHTYPE_NAME(pointer[i]));
		else
		    output_data("%d ",
				pointer[i]);
		if (++i >= length) {
		    output_data("(partial suboption??\?)");
		    break;
		}
		output_data("%s|%s ",
			    ((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
			    "CLIENT" : "SERVER",
			    ((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
			    "MUTUAL" : "ONE-WAY");
		++i;
	    }
	    break;

	case TELQUAL_NAME:
	    i = 2;
	    output_data(" NAME \"%.*s\"",
			length - 2,
			pointer);
	    break;

	default:
	    for (i = 2; i < length; i++) {
		output_data(" ?%d?",
			    pointer[i]);
	    }
	    break;
	}
	break;
#endif

#ifdef ENCRYPTION
    case TELOPT_ENCRYPT:
	output_data("ENCRYPT");
	if (length < 2) {
	    output_data(" (empty suboption?)");
	    break;
	}
	switch (pointer[1]) {
	case ENCRYPT_START:
	    output_data(" START");
	    break;

	case ENCRYPT_END:
	    output_data(" END");
	    break;

	case ENCRYPT_REQSTART:
	    output_data(" REQUEST-START");
	    break;

	case ENCRYPT_REQEND:
	    output_data(" REQUEST-END");
	    break;

	case ENCRYPT_IS:
	case ENCRYPT_REPLY:
	    output_data(" %s ",
			(pointer[1] == ENCRYPT_IS) ?
			"IS" : "REPLY");
	    if (length < 3) {
		output_data(" (partial suboption?)");
		break;
	    }
	    if (ENCTYPE_NAME_OK(pointer[2]))
		output_data("%s ",
			    ENCTYPE_NAME(pointer[2]));
	    else
		output_data(" %d (unknown)",
			    pointer[2]);

	    encrypt_printsub(&pointer[1], length - 1, buf, sizeof(buf));
	    output_data("%s",
			buf);
	    break;

	case ENCRYPT_SUPPORT:
	    i = 2;
	    output_data(" SUPPORT ");
	    while (i < length) {
		if (ENCTYPE_NAME_OK(pointer[i]))
		    output_data("%s ",
				ENCTYPE_NAME(pointer[i]));
		else
		    output_data("%d ",
				pointer[i]);
		i++;
	    }
	    break;

	case ENCRYPT_ENC_KEYID:
	    output_data(" ENC_KEYID %d", pointer[1]);
	    goto encommon;

	case ENCRYPT_DEC_KEYID:
	    output_data(" DEC_KEYID %d", pointer[1]);
	    goto encommon;

	default:
	    output_data(" %d (unknown)", pointer[1]);
	encommon:
	    for (i = 2; i < length; i++) {
		output_data(" %d", pointer[i]);
	    }
	    break;
	}
	break;
#endif

    default:
	if (TELOPT_OK(pointer[0]))
	    output_data("%s (unknown)",
			TELOPT(pointer[0]));
	else
	    output_data("%d (unknown)",
			pointer[i]);
	for (i = 1; i < length; i++) {
	    output_data(" %d", pointer[i]);
	}
	break;
    }
    output_data("\r\n");
}

/*
 * Dump a data buffer in hex and ascii to the output data stream.
 */
void
printdata(char *tag, char *ptr, int cnt)
{
    int i;
    char xbuf[30];

    while (cnt) {
	/* flush net output buffer if no room for new data) */
	if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
	    netflush();
	}

	/* add a line of output */
	output_data("%s: ", tag);
	for (i = 0; i < 20 && cnt; i++) {
	    output_data("%02x", *ptr);
	    if (isprint(*ptr)) {
		xbuf[i] = *ptr;
	    } else {
		xbuf[i] = '.';
	    }
	    if (i % 2) {
		output_data(" ");
	    }
	    cnt--;
	    ptr++;
	}
	xbuf[i] = '\0';
	output_data(" %s\r\n", xbuf);
    }
}
#endif /* DIAGNOSTICS */