main.c

sock5代理服务器源代码

/*
 * Copyright (c) 1985, 1989 Regents of the University of California.
 * All rights reserved.
 *
 * 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 above 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 software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS 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.
 */

#ifndef lint
char copyright[] = 
"@(#) Copyright (c) 1985, 1989 Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

/*
 * FTP User Program -- Command Interface.
 */

#include "ftp_var.h"

#define DONT_NEED_SIGBLOCK
#define DONT_NEED_SIGPAUSE
#define DONT_NEED_SIGUNBLOCK
#define DONT_NEED_SIGPENDING
#include "sigfix.h"

#include <arpa/ftp.h>
#include <errno.h>
#include <ctype.h>
#include <pwd.h>

uid_t	getuid();
void	intr(), lostpeer();
extern	char *home;
char	*getlogin();

#define HELPINDENT (sizeof ("directory"))

struct cmd *getcmd(register char *name) {
    extern struct cmd cmdtab[];
    register char *p, *q;
    register struct cmd *c, *found;
    register int nmatches, longest;
    
    longest = 0;
    nmatches = 0;
    found = 0;
    for (c = cmdtab; (p = c->c_name); c++) {
	for (q = name; *q == *p++; q++)
	    if (*q == 0)		/* exact match? */
		return (c);
	if (!*q) {			/* the name was a prefix */
	    if (q - name > longest) {
		longest = q - name;
		nmatches = 1;
		found = c;
	    } else if (q - name == longest)
		nmatches++;
	}
    }
    
    if (nmatches > 1) return ((struct cmd *)-1);
    return (found);
}

/*
 * Help command.
 * Call each command handler with argc == 0 and argv[0] == name.
 */
void help(int argc, char *argv[]) {
    extern struct cmd cmdtab[];
    register struct cmd *c;
    
    if (argc == 1) {
	register int i, j, w, k;
	int columns, width = 0, lines;
	extern int NCMDS;
	
	printf("Commands may be abbreviated.  Commands are:\n\n");
	for (c = cmdtab; c < &cmdtab[NCMDS]; c++) {
	    int len = strlen(c->c_name);
	    
	    if (len > width)
		width = len;
	}
	width = (width + 8) &~ 7;
	columns = 80 / width;
	if (columns == 0)
	    columns = 1;
	lines = (NCMDS + columns - 1) / columns;
	for (i = 0; i < lines; i++) {
	    for (j = 0; j < columns; j++) {
		c = cmdtab + j * lines + i;
		if (c->c_name && (!proxy || c->c_proxy)) 
		    printf("%s", c->c_name);
		else if (c->c_name) 
		    for (k=0; k < strlen(c->c_name); k++)
			putchar(' ');
		
		if (c + lines >= &cmdtab[NCMDS]) {
		    printf("\n");
		    break;
		}
		w = strlen(c->c_name);
		while (w < width) {
		    w = (w + 8) &~ 7;
		    putchar('\t');
		}
	    }
	}
	return;
    }
    while (--argc > 0) {
	register char *arg;
	arg = *++argv;
	c = getcmd(arg);
	if (c == (struct cmd *)-1)
	    printf("?Ambiguous help command %s\n", arg);
	else if (c == (struct cmd *)0)
	    printf("?Invalid help command %s\n", arg);
	else
	    printf("%-*s\t%s\n", HELPINDENT,
		   c->c_name, c->c_help);
    }
}

/*
 * Command parser.
 */
void cmdscanner(int top) {
    register struct cmd *c;
    register int l;
    
    if (!top)
	putchar('\n');
    for (;;) {
	if (fromatty) {
	    printf("ftp> ");
	    fflush(stdout);
	}
	if (fgets(line, sizeof line, stdin) == NULL)
	    quit();
	l = strlen(line);
	if (l == 0)
	    break;
	if (line[--l] == '\n') {
	    if (l == 0)
		break;
	    line[l] = '\0';
	} else if (l == sizeof(line) - 2) {
	    printf("sorry, input line too long\n");
	    while ((l = getchar()) != '\n' && l != EOF)
		/* void */;
	    break;
	} /* else it was a line without a newline */
	makeargv();
	if (margc == 0) {
	    continue;
	}
	c = getcmd(margv[0]);
	if (c == (struct cmd *)-1) {
	    printf("?Ambiguous command\n");
	    continue;
	}
	if (c == 0) {
	    printf("?Invalid command\n");
	    continue;
	}
	if (c->c_conn && !connected) {
	    printf("Not connected.\n");
	    continue;
	}
	(*c->c_handler)(margc, margv);
	if (bell && c->c_bell)
	    putchar('\007');
	if (c->c_handler != (int (*)())help)
	    break;
    }

    Signal(SIGINT,  intr);
    Signal(SIGPIPE, lostpeer);
}

void intr() {
    longjmp(toplevel, 1);
}

void lostpeer() {
    extern FILE *cout;
    extern int data;

    if (connected) {
	if (cout != NULL) {
	    shutdown(fileno(cout), 1+1);
	    fclose(cout);
	    cout = NULL;
	}

	if (data >= 0) {
	    shutdown(data, 1+1);
	    close(data);
	    data = -1;
	}

	connected = 0;
    }

    pswitch(1);

    if (connected) {
	if (cout != NULL) {
	    shutdown(fileno(cout), 1+1);
	    fclose(cout);
	    cout = NULL;
	}

	connected = 0;
    }

    proxflag = 0;
    pswitch(0);
}

/*
 * Slice a string up into argc/argv.
 */

int slrflag;

/*
 * Parse string into argbuf;
 * implemented with FSM to
 * handle quoting and strings
 */
char *slurpstring() {
    int got_one = 0;
    register char *sb = stringbase;
    register char *ap = argbase;
    char *tmp = argbase;		/* will return this if token found */
    
    if (*sb == '!' || *sb == '$') {	/* recognize ! as a token for shell */
	switch (slrflag) {	         /* and $ as token for macro invoke */
	    case 0:
		slrflag++;
		stringbase++;
		return ((*sb == '!') ? "!" : "$");
		/* NOTREACHED */
	    case 1:
		slrflag++;
		altarg = stringbase;
		break;
	    default:
		break;
	}
    }
    
  S0:
    switch (*sb) {
	case '\0':
	    goto OUT;
	    
	case ' ':
	case '\t':
	    sb++; goto S0;

	default:
	    switch (slrflag) {
		case 0:
		    slrflag++;
		    break;
		case 1:
		    slrflag++;
		    altarg = sb;
		    break;
		default:
		    break;
	    }

		    goto S1;
    }
    
  S1:
    switch (*sb) {
	case ' ':
	case '\t':
	case '\0':
	    goto OUT;	/* end of token */
	    
	case '\\':
	    sb++; goto S2;	/* slurp next character */
	    
	case '"':
	    sb++; goto S3;	/* slurp quoted string */
	    
	default:
	    *ap++ = *sb++;	/* add character to token */
	    got_one = 1;
	    goto S1;
    }
    
  S2:
    switch (*sb) {
	case '\0':
	    goto OUT;
	    
	default:
	    *ap++ = *sb++;
	    got_one = 1;
	    goto S1;
    }
    
  S3:
    switch (*sb) {
	case '\0':
	    goto OUT;
	    
	case '"':
	    sb++; goto S1;
	    
	default:
	    *ap++ = *sb++;
	    got_one = 1;
	    goto S3;
	}

  OUT:
    if (got_one) {
	*ap++ = '\0';
    }

    argbase = ap;			/* update storage pointer */
    stringbase = sb;		        /* update scan pointer */
    if (got_one) {
	return(tmp);
    }

    switch (slrflag) {
	case 0:
	    slrflag++;
	    break;
	case 1:
	    slrflag++;
	    altarg = (char *) 0;
	    break;
	default:
	    break;
    }

    return((char *)0);
}

void makeargv() {
    char **argp;
    
    margc = 0;
    argp = margv;
    stringbase = line;		/* scan from first of buffer */
    argbase = argbuf;		/* store from first of buffer */
    slrflag = 0;

    while ((*argp++ = slurpstring())) margc++;
}

int main(int argc, char *argv[]) {
    register char *cp;
    struct passwd *pw = NULL;
    char homedir[MAXPATHLEN];
    int top;
    
#ifdef SOCKS
    LIBPREFIX2(init)(argv[0]);
#endif
    
#ifdef FASCIST
    fprintf(stderr,"***NOTE: Names of all files transferred will be recorded! \n");
#endif
    
    if ((sp = getservbyname("ftp", "tcp")) == 0) {
	fprintf(stderr, "ftp: ftp/tcp: unknown service\n");
	exit(1);
    }

    /* save ftp's s_port value so it won't be clobbered by by another call   */
    /* to getserbyname()                                                     */
    ftp_s_port = sp->s_port;
    doglob = 1;
    interactive = 1;
    autologin = 1;
    argc--, argv++;

    while (argc > 0 && **argv == '-') {
	for (cp = *argv + 1; *cp; cp++)
	    switch (*cp) {
		case 'd':
		    options |= SO_DEBUG;
		    debug++;
		    break;
			
		case 'v':
		    verbose++;
		    break;
		    
		case 't':
		    trace++;
		    break;
		    
		case 'i':
		    interactive = 0;
		    break;
		    
		case 'n':
		    autologin = 0;
		    break;
		    
		case 'g':
		    doglob = 0;
		    break;
		    
		default:
		    fprintf(stdout, "ftp: %c: unknown option\n", *cp);
		    exit(1);
	    }

	argc--, argv++;
    }

    fromatty = isatty(fileno(stdin));
    if (fromatty) verbose++;

    cpend = 0;	/* no pending replies */
    proxy = 0;	/* proxy not active */
    crflag = 1;	/* strip c.r. on ascii gets */
    sendport = -1;	/* not using ports */

    /*  Set up the home directory in case we're globbing.                    */
    if ((cp = getlogin()) != NULL) {
	pw = getpwnam(cp);
    }

    if (pw == NULL) {
	pw = getpwuid(getuid());
    }

    if (pw != NULL) {
	home = homedir;
	strcpy(home, pw->pw_dir);
    }

    if (argc > 0) {
	if (setjmp(toplevel)) exit(0);
	Signal(SIGINT, intr);
	Signal(SIGPIPE, lostpeer);
	setpeer(argc + 1, argv - 1);
    }

    top = setjmp(toplevel) == 0;

    if (top) {
	Signal(SIGINT, intr);
	Signal(SIGPIPE, lostpeer);
    }

    for (;;) {
	cmdscanner(top);
	top = 1;
    }
}