nanoftp.c

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 */
static int
xmlNanoFTPParseResponse(char *buf, int len) {
    int val = 0;

    if (len < 3) return(-1);
    if ((*buf >= '0') && (*buf <= '9')) 
        val = val * 10 + (*buf - '0');
    else
        return(0);
    buf++;
    if ((*buf >= '0') && (*buf <= '9')) 
        val = val * 10 + (*buf - '0');
    else
        return(0);
    buf++;
    if ((*buf >= '0') && (*buf <= '9')) 
        val = val * 10 + (*buf - '0');
    else
        return(0);
    buf++;
    if (*buf == '-') 
        return(-val);
    return(val);
}

/**
 * xmlNanoFTPGetMore:
 * @ctx:  an FTP context
 *
 * Read more information from the FTP control connection
 * Returns the number of bytes read, < 0 indicates an error
 */
static int
xmlNanoFTPGetMore(void *ctx) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    int len;
    int size;

    if ((ctxt == NULL) || (ctxt->controlFd < 0)) return(-1);

    if ((ctxt->controlBufIndex < 0) || (ctxt->controlBufIndex > FTP_BUF_SIZE)) {
#ifdef DEBUG_FTP
        xmlGenericError(xmlGenericErrorContext,
		"xmlNanoFTPGetMore : controlBufIndex = %d\n",
		ctxt->controlBufIndex);
#endif
	return(-1);
    }

    if ((ctxt->controlBufUsed < 0) || (ctxt->controlBufUsed > FTP_BUF_SIZE)) {
#ifdef DEBUG_FTP
        xmlGenericError(xmlGenericErrorContext,
		"xmlNanoFTPGetMore : controlBufUsed = %d\n",
		ctxt->controlBufUsed);
#endif
	return(-1);
    }
    if (ctxt->controlBufIndex > ctxt->controlBufUsed) {
#ifdef DEBUG_FTP
        xmlGenericError(xmlGenericErrorContext,
		"xmlNanoFTPGetMore : controlBufIndex > controlBufUsed %d > %d\n",
	       ctxt->controlBufIndex, ctxt->controlBufUsed);
#endif
	return(-1);
    }

    /*
     * First pack the control buffer
     */
    if (ctxt->controlBufIndex > 0) {
	memmove(&ctxt->controlBuf[0], &ctxt->controlBuf[ctxt->controlBufIndex],
		ctxt->controlBufUsed - ctxt->controlBufIndex);
	ctxt->controlBufUsed -= ctxt->controlBufIndex;
	ctxt->controlBufIndex = 0;
    }
    size = FTP_BUF_SIZE - ctxt->controlBufUsed;
    if (size == 0) {
#ifdef DEBUG_FTP
        xmlGenericError(xmlGenericErrorContext,
		"xmlNanoFTPGetMore : buffer full %d \n", ctxt->controlBufUsed);
#endif
	return(0);
    }

    /*
     * Read the amount left on the control connection
     */
    if ((len = recv(ctxt->controlFd, &ctxt->controlBuf[ctxt->controlBufIndex],
		    size, 0)) < 0) {
	__xmlIOErr(XML_FROM_FTP, 0, "recv failed");
	closesocket(ctxt->controlFd); ctxt->controlFd = -1;
        ctxt->controlFd = -1;
        return(-1);
    }
#ifdef DEBUG_FTP
    xmlGenericError(xmlGenericErrorContext,
	    "xmlNanoFTPGetMore : read %d [%d - %d]\n", len,
	   ctxt->controlBufUsed, ctxt->controlBufUsed + len);
#endif
    ctxt->controlBufUsed += len;
    ctxt->controlBuf[ctxt->controlBufUsed] = 0;

    return(len);
}

/**
 * xmlNanoFTPReadResponse:
 * @ctx:  an FTP context
 *
 * Read the response from the FTP server after a command.
 * Returns the code number
 */
static int
xmlNanoFTPReadResponse(void *ctx) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    char *ptr, *end;
    int len;
    int res = -1, cur = -1;

    if ((ctxt == NULL) || (ctxt->controlFd < 0)) return(-1);

get_more:
    /*
     * Assumes everything up to controlBuf[controlBufIndex] has been read
     * and analyzed.
     */
    len = xmlNanoFTPGetMore(ctx);
    if (len < 0) {
        return(-1);
    }
    if ((ctxt->controlBufUsed == 0) && (len == 0)) {
        return(-1);
    }
    ptr = &ctxt->controlBuf[ctxt->controlBufIndex];
    end = &ctxt->controlBuf[ctxt->controlBufUsed];

#ifdef DEBUG_FTP
    xmlGenericError(xmlGenericErrorContext,
	    "\n<<<\n%s\n--\n", ptr);
#endif
    while (ptr < end) {
        cur = xmlNanoFTPParseResponse(ptr, end - ptr);
	if (cur > 0) {
	    /*
	     * Successfully scanned the control code, scratch
	     * till the end of the line, but keep the index to be
	     * able to analyze the result if needed.
	     */
	    res = cur;
	    ptr += 3;
	    ctxt->controlBufAnswer = ptr - ctxt->controlBuf;
	    while ((ptr < end) && (*ptr != '\n')) ptr++;
	    if (*ptr == '\n') ptr++;
	    if (*ptr == '\r') ptr++;
	    break;
	}
	while ((ptr < end) && (*ptr != '\n')) ptr++;
	if (ptr >= end) {
	    ctxt->controlBufIndex = ctxt->controlBufUsed;
	    goto get_more;
	}
	if (*ptr != '\r') ptr++;
    }

    if (res < 0) goto get_more;
    ctxt->controlBufIndex = ptr - ctxt->controlBuf;
#ifdef DEBUG_FTP
    ptr = &ctxt->controlBuf[ctxt->controlBufIndex];
    xmlGenericError(xmlGenericErrorContext, "\n---\n%s\n--\n", ptr);
#endif

#ifdef DEBUG_FTP
    xmlGenericError(xmlGenericErrorContext, "Got %d\n", res);
#endif
    return(res / 100);
}

/**
 * xmlNanoFTPGetResponse:
 * @ctx:  an FTP context
 *
 * Get the response from the FTP server after a command.
 * Returns the code number
 */

int
xmlNanoFTPGetResponse(void *ctx) {
    int res;

    res = xmlNanoFTPReadResponse(ctx);

    return(res);
}

/**
 * xmlNanoFTPCheckResponse:
 * @ctx:  an FTP context
 *
 * Check if there is a response from the FTP server after a command.
 * Returns the code number, or 0
 */

int
xmlNanoFTPCheckResponse(void *ctx) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    fd_set rfd;
    struct timeval tv;

    if ((ctxt == NULL) || (ctxt->controlFd < 0)) return(-1);
    tv.tv_sec = 0;
    tv.tv_usec = 0;
    FD_ZERO(&rfd);
    FD_SET(ctxt->controlFd, &rfd);
    switch(select(ctxt->controlFd + 1, &rfd, NULL, NULL, &tv)) {
	case 0:
	    return(0);
	case -1:
	    __xmlIOErr(XML_FROM_FTP, 0, "select");
	    return(-1);
			
    }

    return(xmlNanoFTPReadResponse(ctx));
}

/**
 * Send the user authentication
 */

static int
xmlNanoFTPSendUser(void *ctx) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    char buf[200];
    int len;
    int res;

    if (ctxt->user == NULL)
	snprintf(buf, sizeof(buf), "USER anonymous\r\n");
    else
	snprintf(buf, sizeof(buf), "USER %s\r\n", ctxt->user);
    buf[sizeof(buf) - 1] = 0;
    len = strlen(buf);
#ifdef DEBUG_FTP
    xmlGenericError(xmlGenericErrorContext, "%s", buf);
#endif
    res = send(ctxt->controlFd, buf, len, 0);
    if (res < 0) {
	__xmlIOErr(XML_FROM_FTP, 0, "send failed");
	return(res);
    }
    return(0);
}

/**
 * Send the password authentication
 */

static int
xmlNanoFTPSendPasswd(void *ctx) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    char buf[200];
    int len;
    int res;

    if (ctxt->passwd == NULL)
	snprintf(buf, sizeof(buf), "PASS anonymous@\r\n");
    else
	snprintf(buf, sizeof(buf), "PASS %s\r\n", ctxt->passwd);
    buf[sizeof(buf) - 1] = 0;
    len = strlen(buf);
#ifdef DEBUG_FTP
    xmlGenericError(xmlGenericErrorContext, "%s", buf);
#endif
    res = send(ctxt->controlFd, buf, len, 0);
    if (res < 0) {
	__xmlIOErr(XML_FROM_FTP, 0, "send failed");
	return(res);
    }
    return(0);
}

/**
 * xmlNanoFTPQuit:
 * @ctx:  an FTP context
 *
 * Send a QUIT command to the server
 *
 * Returns -1 in case of error, 0 otherwise
 */


int
xmlNanoFTPQuit(void *ctx) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    char buf[200];
    int len, res;

    if ((ctxt == NULL) || (ctxt->controlFd < 0)) return(-1);

    snprintf(buf, sizeof(buf), "QUIT\r\n");
    len = strlen(buf);
#ifdef DEBUG_FTP
    xmlGenericError(xmlGenericErrorContext, "%s", buf); /* Just to be consistent, even though we know it can't have a % in it */
#endif
    res = send(ctxt->controlFd, buf, len, 0);
    if (res < 0) {
	__xmlIOErr(XML_FROM_FTP, 0, "send failed");
	return(res);
    }
    return(0);
}

/**
 * xmlNanoFTPConnect:
 * @ctx:  an FTP context
 *
 * Tries to open a control connection
 *
 * Returns -1 in case of error, 0 otherwise
 */

int
xmlNanoFTPConnect(void *ctx) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    struct hostent *hp;
    int port;
    int res;
    int addrlen = sizeof (struct sockaddr_in);

    if (ctxt == NULL)
	return(-1);
    if (ctxt->hostname == NULL)
	return(-1);

    /*
     * do the blocking DNS query.
     */
    if (proxy) {
        port = proxyPort;
    } else {
	port = ctxt->port;
    }
    if (port == 0)
	port = 21;

    memset (&ctxt->ftpAddr, 0, sizeof(ctxt->ftpAddr));

#ifdef SUPPORT_IP6
    if (have_ipv6 ()) {
	struct addrinfo hints, *tmp, *result;

	result = NULL;
	memset (&hints, 0, sizeof(hints));
	hints.ai_socktype = SOCK_STREAM;

	if (proxy) {
	    if (getaddrinfo (proxy, NULL, &hints, &result) != 0) {
		__xmlIOErr(XML_FROM_FTP, 0, "getaddrinfo failed");
		return (-1);
	    }
	}
	else
	    if (getaddrinfo (ctxt->hostname, NULL, &hints, &result) != 0) {
		__xmlIOErr(XML_FROM_FTP, 0, "getaddrinfo failed");
		return (-1);
	    }

	for (tmp = result; tmp; tmp = tmp->ai_next)
	    if (tmp->ai_family == AF_INET || tmp->ai_family == AF_INET6)
		break;

	if (!tmp) {
	    if (result)
		freeaddrinfo (result);
	    __xmlIOErr(XML_FROM_FTP, 0, "getaddrinfo failed");
	    return (-1);
	}
	if (tmp->ai_addrlen > sizeof(ctxt->ftpAddr)) {
	    __xmlIOErr(XML_FROM_FTP, 0, "gethostbyname address mismatch");
	    return (-1);
	}
	if (tmp->ai_family == AF_INET6) {
	    memcpy (&ctxt->ftpAddr, tmp->ai_addr, tmp->ai_addrlen);
	    ((struct sockaddr_in6 *) &ctxt->ftpAddr)->sin6_port = htons (port);
	    ctxt->controlFd = socket (AF_INET6, SOCK_STREAM, 0);
	}
	else {
	    memcpy (&ctxt->ftpAddr, tmp->ai_addr, tmp->ai_addrlen);
	    ((struct sockaddr_in *) &ctxt->ftpAddr)->sin_port = htons (port);
	    ctxt->controlFd = socket (AF_INET, SOCK_STREAM, 0);
	}
	addrlen = tmp->ai_addrlen;
	freeaddrinfo (result);
    }
    else
#endif
    {
	if (proxy)
	    hp = gethostbyname (proxy);
	else
	    hp = gethostbyname (ctxt->hostname);
	if (hp == NULL) {
	    __xmlIOErr(XML_FROM_FTP, 0, "gethostbyname failed");
	    return (-1);
	}
	if ((unsigned int) hp->h_length >
	    sizeof(((struct sockaddr_in *)&ctxt->ftpAddr)->sin_addr)) {
	    __xmlIOErr(XML_FROM_FTP, 0, "gethostbyname address mismatch");
	    return (-1);
	}

	/*
	 * Prepare the socket
	 */
	((struct sockaddr_in *)&ctxt->ftpAddr)->sin_family = AF_INET;
	memcpy (&((struct sockaddr_in *)&ctxt->ftpAddr)->sin_addr,
		hp->h_addr_list[0], hp->h_length);
	((struct sockaddr_in *)&ctxt->ftpAddr)->sin_port = htons (port);
	ctxt->controlFd = socket (AF_INET, SOCK_STREAM, 0);
	addrlen = sizeof (struct sockaddr_in);
    }

    if (ctxt->controlFd < 0) {
	__xmlIOErr(XML_FROM_FTP, 0, "socket failed");
        return(-1);
    }

    /*
     * Do the connect.
     */
    if (connect(ctxt->controlFd, (struct sockaddr *) &ctxt->ftpAddr,
	    addrlen) < 0) {
	__xmlIOErr(XML_FROM_FTP, 0, "Failed to create a connection");
        closesocket(ctxt->controlFd); ctxt->controlFd = -1;
        ctxt->controlFd = -1;
	return(-1);
    }

    /*
     * Wait for the HELLO from the server.
     */
    res = xmlNanoFTPGetResponse(ctxt);
    if (res != 2) {
        closesocket(ctxt->controlFd); ctxt->controlFd = -1;
        ctxt->controlFd = -1;
	return(-1);
    }

    /*
     * State diagram for the login operation on the FTP server
     *
     * Reference: RFC 959
     *
     *                       1
     * +---+   USER    +---+------------->+---+
     * | B |---------->| W | 2       ---->| E |
     * +---+           +---+------  |  -->+---+
     *                  | |       | | |
     *                3 | | 4,5   | | |
     *    --------------   -----  | | |
     *   |                      | | | |
     *   |                      | | | |
     *   |                 ---------  |
     *   |               1|     | |   |
     *   V                |     | |   |
     * +---+   PASS    +---+ 2  |  ------>+---+
     * |   |---------->| W |------------->| S |
     * +---+           +---+   ---------->+---+
     *                  | |   | |     |
     *                3 | |4,5| |     |
     *    --------------   --------   |
     *   |                    | |  |  |
     *   |                    | |  |  |
     *   |                 -----------
     *   |             1,3|   | |  |
     *   V                |  2| |  |
     * +---+   ACCT    +---+--  |   ----->+---+
     * |   |---------->| W | 4,5 -------->| F |
     * +---+           +---+------------->+---+
     *
     * Of course in case of using a proxy this get really nasty and is not
     * standardized at all :-(
     */
    if (proxy) {
        int len;
	char buf[400];

        if (proxyUser != NULL) {
	    /*
	     * We need proxy auth
	     */
	    snprintf(buf, sizeof(buf), "USER %s\r\n", proxyUser);
            buf[sizeof(buf) - 1] = 0;
            len = strlen(buf);
#ifdef DEBUG_FTP
	    xmlGenericError(xmlGenericErrorContext, "%s", buf);
#endif
	    res = send(ctxt->controlFd, buf, len, 0);
	    if (res < 0) {
		__xmlIOErr(XML_FROM_FTP, 0, "send failed");
		closesocket(ctxt->controlFd);
		ctxt->controlFd = -1;
	        return(res);
	    }
	    res = xmlNanoFTPGetResponse(ctxt);
	    switch (res) {
		case 2:
		    if (proxyPasswd == NULL)
			break;
		case 3:
		    if (proxyPasswd != NULL)
			snprintf(buf, sizeof(buf), "PASS %s\r\n", proxyPasswd);
		    else
			snprintf(buf, sizeof(buf), "PASS anonymous@\r\n");
                    buf[sizeof(buf) - 1] = 0;
                    len = strlen(buf);
#ifdef DEBUG_FTP
		    xmlGenericError(xmlGenericErrorContext, "%s", buf);
#endif
		    res = send(ctxt->controlFd, buf, len, 0);
		    if (res < 0) {
			__xmlIOErr(XML_FROM_FTP, 0, "send failed");
			closesocket(ctxt->controlFd);
			ctxt->controlFd = -1;
			return(res);
		    }
		    res = xmlNanoFTPGetResponse(ctxt);