nanoftp.c

SIP 1.5.0源代码

/**
 * ftp.c: basic handling of an FTP command connection to check for
 *        directory availability. No transfer is needed.
 *
 *  Reference: RFC 959
 */

#include "global.h"
#ifdef WIN32
#define INCLUDE_WINSOCK
#include "win32config.h"
#else
#include "config.h"
#endif
#include "xmlversion.h"

#ifdef LIBXML_FTP_ENABLED
#include <stdio.h>
#include <string.h>

#ifdef HAVE_CTYPE_H
#include <ctype.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include <sys/types.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h> 
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#ifdef HAVE_RESOLV_H
#include <resolv.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRINGS_H
#include <strings.h>
#endif

#include <libxml/xmlmemory.h>
#include <libxml/nanoftp.h>

/* #define DEBUG_FTP 1  */
#ifdef STANDALONE
#ifndef DEBUG_FTP
#define DEBUG_FTP 1
#endif
#endif

static char hostname[100];

#define FTP_COMMAND_OK		200
#define FTP_SYNTAX_ERROR	500
#define FTP_GET_PASSWD		331

typedef struct xmlNanoFTPCtxt {
    char *protocol;	/* the protocol name */
    char *hostname;	/* the host name */
    int port;		/* the port */
    char *path;		/* the path within the URL */
    char *user;		/* user string */
    char *passwd;	/* passwd string */
    struct sockaddr_in ftpAddr; /* the socket address struct */
    int passive;	/* currently we support only passive !!! */
    int controlFd;	/* the file descriptor for the control socket */
    int dataFd;		/* the file descriptor for the data socket */
    int state;		/* WRITE / READ / CLOSED */
    int returnValue;	/* the protocol return value */
} xmlNanoFTPCtxt, *xmlNanoFTPCtxtPtr;

static int initialized = 0;
static char *proxy = NULL;	/* the proxy name if any */
static int proxyPort = 0;	/* the proxy port if any */
static char *proxyUser = NULL;	/* user for proxy authentication */
static char *proxyPasswd = NULL;/* passwd for proxy authentication */
static int proxyType = 0;	/* uses TYPE or a@b ? */

/**
 * xmlNanoFTPInit:
 *
 * Initialize the FTP protocol layer.
 * Currently it just checks for proxy informations,
 * and get the hostname
 */

void
xmlNanoFTPInit(void) {
    const char *env;

    if (initialized)
	return;

    gethostname(hostname, sizeof(hostname));

    proxyPort = 21;
    env = getenv("no_proxy");
    if (env != NULL)
	return;
    env = getenv("ftp_proxy");
    if (env != NULL) {
	xmlNanoFTPScanProxy(env);
    } else {
	env = getenv("FTP_PROXY");
	if (env != NULL) {
	    xmlNanoFTPScanProxy(env);
	}
    }
    env = getenv("ftp_proxy_user");
    if (env != NULL) {
	proxyUser = xmlMemStrdup(env);
    }
    env = getenv("ftp_proxy_password");
    if (env != NULL) {
	proxyPasswd = xmlMemStrdup(env);
    }
    initialized = 1;
}

/**
 * xmlNanoFTPClenup:
 *
 * Cleanup the FTP protocol layer. This cleanup proxy informations.
 */

void
xmlNanoFTPCleanup(void) {
    if (proxy != NULL) {
	xmlFree(proxy);
	proxy = NULL;
    }
    if (proxyUser != NULL) {
	xmlFree(proxyUser);
	proxyUser = NULL;
    }
    if (proxyPasswd != NULL) {
	xmlFree(proxyPasswd);
	proxyPasswd = NULL;
    }
    hostname[0] = 0;
    initialized = 0;
    return;
}

/**
 * xmlNanoFTPProxy:
 * @host:  the proxy host name
 * @port:  the proxy port
 * @user:  the proxy user name
 * @passwd:  the proxy password
 * @type:  the type of proxy 1 for using SITE, 2 for USER a@b
 *
 * Setup the FTP proxy informations.
 * This can also be done by using ftp_proxy ftp_proxy_user and
 * ftp_proxy_password environment variables.
 */

void
xmlNanoFTPProxy(const char *host, int port, const char *user,
	        const char *passwd, int type) {
    if (proxy != NULL)
	xmlFree(proxy);
    if (proxyUser != NULL)
	xmlFree(proxyUser);
    if (proxyPasswd != NULL)
	xmlFree(proxyPasswd);
    if (host)
	proxy = xmlMemStrdup(host);
    if (user)
	proxyUser = xmlMemStrdup(user);
    if (passwd)
	proxyPasswd = xmlMemStrdup(passwd);
    proxyPort = port;
    proxyType = type;
}

/**
 * xmlNanoFTPScanURL:
 * @ctx:  an FTP context
 * @URL:  The URL used to initialize the context
 *
 * (Re)Initialize an FTP context by parsing the URL and finding
 * the protocol host port and path it indicates.
 */

static void
xmlNanoFTPScanURL(void *ctx, const char *URL) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    const char *cur = URL;
    char buf[4096];
    int index = 0;
    int port = 0;

    if (ctxt->protocol != NULL) { 
        xmlFree(ctxt->protocol);
	ctxt->protocol = NULL;
    }
    if (ctxt->hostname != NULL) { 
        xmlFree(ctxt->hostname);
	ctxt->hostname = NULL;
    }
    if (ctxt->path != NULL) { 
        xmlFree(ctxt->path);
	ctxt->path = NULL;
    }
    if (URL == NULL) return;
    buf[index] = 0;
    while (*cur != 0) {
        if ((cur[0] == ':') && (cur[1] == '/') && (cur[2] == '/')) {
	    buf[index] = 0;
	    ctxt->protocol = xmlMemStrdup(buf);
	    index = 0;
            cur += 3;
	    break;
	}
	buf[index++] = *cur++;
    }
    if (*cur == 0) return;

    buf[index] = 0;
    while (1) {
        if (cur[0] == ':') {
	    buf[index] = 0;
	    ctxt->hostname = xmlMemStrdup(buf);
	    index = 0;
	    cur += 1;
	    while ((*cur >= '0') && (*cur <= '9')) {
	        port *= 10;
		port += *cur - '0';
		cur++;
	    }
	    if (port != 0) ctxt->port = port;
	    while ((cur[0] != '/') && (*cur != 0)) 
	        cur++;
	    break;
	}
        if ((*cur == '/') || (*cur == 0)) {
	    buf[index] = 0;
	    ctxt->hostname = xmlMemStrdup(buf);
	    index = 0;
	    break;
	}
	buf[index++] = *cur++;
    }
    if (*cur == 0) 
        ctxt->path = xmlMemStrdup("/");
    else {
        index = 0;
        buf[index] = 0;
	while (*cur != 0)
	    buf[index++] = *cur++;
	buf[index] = 0;
	ctxt->path = xmlMemStrdup(buf);
    }	
}

/**
 * xmlNanoFTPUpdateURL:
 * @ctx:  an FTP context
 * @URL:  The URL used to update the context
 *
 * Update an FTP context by parsing the URL and finding
 * new path it indicates. If there is an error in the 
 * protocol, hostname, port or other information, the
 * error is raised. It indicates a new connection has to
 * be established.
 *
 * Returns 0 if Ok, -1 in case of error (other host).
 */

int
xmlNanoFTPUpdateURL(void *ctx, const char *URL) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    const char *cur = URL;
    char buf[4096];
    int index = 0;
    int port = 0;

    if (URL == NULL)
	return(-1);
    if (ctxt == NULL)
	return(-1);
    if (ctxt->protocol == NULL)
	return(-1);
    if (ctxt->hostname == NULL)
	return(-1);
    buf[index] = 0;
    while (*cur != 0) {
        if ((cur[0] == ':') && (cur[1] == '/') && (cur[2] == '/')) {
	    buf[index] = 0;
	    if (strcmp(ctxt->protocol, buf))
		return(-1);
	    index = 0;
            cur += 3;
	    break;
	}
	buf[index++] = *cur++;
    }
    if (*cur == 0)
	return(-1);

    buf[index] = 0;
    while (1) {
        if (cur[0] == ':') {
	    buf[index] = 0;
	    if (strcmp(ctxt->hostname, buf))
		return(-1);
	    index = 0;
	    cur += 1;
	    while ((*cur >= '0') && (*cur <= '9')) {
	        port *= 10;
		port += *cur - '0';
		cur++;
	    }
	    if (port != ctxt->port)
		return(-1);
	    while ((cur[0] != '/') && (*cur != 0)) 
	        cur++;
	    break;
	}
        if ((*cur == '/') || (*cur == 0)) {
	    buf[index] = 0;
	    if (strcmp(ctxt->hostname, buf))
		return(-1);
	    index = 0;
	    break;
	}
	buf[index++] = *cur++;
    }
    if (ctxt->path != NULL) {
	xmlFree(ctxt->path);
	ctxt->path = NULL;
    }

    if (*cur == 0) 
        ctxt->path = xmlMemStrdup("/");
    else {
        index = 0;
        buf[index] = 0;
	while (*cur != 0)
	    buf[index++] = *cur++;
	buf[index] = 0;
	ctxt->path = xmlMemStrdup(buf);
    }	
    return(0);
}

/**
 * xmlNanoFTPScanProxy:
 * @URL:  The proxy URL used to initialize the proxy context
 *
 * (Re)Initialize the FTP Proxy context by parsing the URL and finding
 * the protocol host port it indicates.
 * Should be like ftp://myproxy/ or ftp://myproxy:3128/
 * A NULL URL cleans up proxy informations.
 */

void
xmlNanoFTPScanProxy(const char *URL) {
    const char *cur = URL;
    char buf[4096];
    int index = 0;
    int port = 0;

    if (proxy != NULL) { 
        xmlFree(proxy);
	proxy = NULL;
    }
    if (proxyPort != 0) { 
	proxyPort = 0;
    }
#ifdef DEBUG_FTP
    if (URL == NULL)
	printf("Removing FTP proxy info\n");
    else
	printf("Using FTP proxy %s\n", URL);
#endif
    if (URL == NULL) return;
    buf[index] = 0;
    while (*cur != 0) {
        if ((cur[0] == ':') && (cur[1] == '/') && (cur[2] == '/')) {
	    buf[index] = 0;
	    index = 0;
            cur += 3;
	    break;
	}
	buf[index++] = *cur++;
    }
    if (*cur == 0) return;

    buf[index] = 0;
    while (1) {
        if (cur[0] == ':') {
	    buf[index] = 0;
	    proxy = xmlMemStrdup(buf);
	    index = 0;
	    cur += 1;
	    while ((*cur >= '0') && (*cur <= '9')) {
	        port *= 10;
		port += *cur - '0';
		cur++;
	    }
	    if (port != 0) proxyPort = port;
	    while ((cur[0] != '/') && (*cur != 0)) 
	        cur++;
	    break;
	}
        if ((*cur == '/') || (*cur == 0)) {
	    buf[index] = 0;
	    proxy = xmlMemStrdup(buf);
	    index = 0;
	    break;
	}
	buf[index++] = *cur++;
    }
}

/**
 * xmlNanoFTPNewCtxt:
 * @URL:  The URL used to initialize the context
 *
 * Allocate and initialize a new FTP context.
 *
 * Returns an FTP context or NULL in case of error.
 */

void *
xmlNanoFTPNewCtxt(const char *URL) {
    xmlNanoFTPCtxtPtr ret;

    ret = (xmlNanoFTPCtxtPtr) xmlMalloc(sizeof(xmlNanoFTPCtxt));
    if (ret == NULL) return(NULL);

    memset(ret, 0, sizeof(xmlNanoFTPCtxt));
    ret->port = 21;
    ret->passive = 1;
    ret->returnValue = 0;

    if (URL != NULL)
	xmlNanoFTPScanURL(ret, URL);

    return(ret);
}

/**
 * xmlNanoFTPFreeCtxt:
 * @ctx:  an FTP context
 *
 * Frees the context after closing the connection.
 */

void
xmlNanoFTPFreeCtxt(void * ctx) {
    xmlNanoFTPCtxtPtr ctxt = (xmlNanoFTPCtxtPtr) ctx;
    if (ctxt == NULL) return;
    if (ctxt->hostname != NULL) xmlFree(ctxt->hostname);
    if (ctxt->protocol != NULL) xmlFree(ctxt->protocol);
    if (ctxt->path != NULL) xmlFree(ctxt->path);
    ctxt->passive = 1;
    if (ctxt->controlFd >= 0) close(ctxt->controlFd);
    ctxt->controlFd = -1;
    xmlFree(ctxt);
}

/**
 * Parsing of the server answer, we just extract the code.
 * return 0 for errors
 *     +XXX for last line of response
 *     -XXX for response to be continued
 */
static int
xmlNanoFTPParseResponse(void *ctx, 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);
}

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

    if (size <= 0) return(-1);

get_more:
    if ((len = recv(ctxt->controlFd, buf, size - 1, 0)) < 0) {
	close(ctxt->controlFd); ctxt->controlFd = -1;
        ctxt->controlFd = -1;
        return(-1);
    }
    if (len == 0) {
        return(-1);
    }

    end = &buf[len];
    *end = 0;
#ifdef DEBUG_FTP
    printf(buf);
#endif
    ptr = buf;
    while (ptr < end) {
        res = xmlNanoFTPParseResponse(ctxt, ptr, end - ptr);
	if (res > 0) break;
	if (res == 0) {
#ifdef DEBUG_FTP
	    fprintf(stderr, "xmlNanoFTPReadResponse failed: %s\n", ptr);
#endif
	    return(-1);
	}
	while ((ptr < end) && (*ptr != '\n')) ptr++;
	if (ptr >= end) {
#ifdef DEBUG_FTP
	    fprintf(stderr, "xmlNanoFTPReadResponse: unexpected end %s\n", buf);
#endif
	    return((-res) / 100);
	}
	if (*ptr != '\r') ptr++;
    }

    if (res < 0) goto get_more;

#ifdef DEBUG_FTP
    printf("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) {
    char buf[16 * 1024 + 1];

/**************
    fd_set rfd;
    struct timeval tv;
    int res;

    tv.tv_sec = 10;
    tv.tv_usec = 0;
    FD_ZERO(&rfd);
    FD_SET(ctxt->controlFd, &rfd);
    res = select(ctxt->controlFd + 1, &rfd, NULL, NULL, &tv);
    if (res <= 0) return(res);
 **************/

    return(xmlNanoFTPReadResponse(ctx, buf, 16 * 1024));
}

/**