stupid-ftpd(嵌入式Linux平台)

/* ftpcommand.c ------------ FTP-protocol request handlers. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <ctype.h> #include <sys/stat.h> #include <time.h> #include <sys/time.h> #include <sys/types.h> #ifdef __CYGWIN__ #include <winsock2.h> #else #include <unistd.h> #include <sys/socket.h> #include <sys/param.h> #include <netdb.h> #include <netinet/in.h> #include <arpa/inet.h> #endif #include <signal.h> #include <errno.h> #include "ftpcommand.h" #include "stupid-ftpd.h" #include "ftpdconfig.h" #include "ftperror.h" #include "ls.h" #define TRFMSG_INTERVAL 1000000 #define REQ_COUNT 23 const char *request[REQ_COUNT]={ "SYST","QUIT","TYPE","PORT","LIST","CWD","PWD","RETR", "USER","PASS","REST","SIZE","MDTM","STOR","CDUP","NOOP","GET", "NLST","PASV","ABOR","MKD","RMD","DELE" }; const char *ftp_returnstr[]={ "150 OK\r\n", "501 Error in parameters.\r\n", "226 Transfer complete.\r\n", "221 Bye.\r\n", "425 Can't open passive connection.\r\n", "428 Server shutdown.\r\n", "429 Server restart.\r\n", "530 Server is busy, sorry.\r\n", "220 Welcome to Stupid-FTPd server.\r\n", "331 Guest login ok, send your e-mail address as password.\r\n", "531 Anonymous access denied.\r\n", "532 Login incorrect.\r\n", "533 No multiple logins allowed.\r\n", "534 Home directory not found.\r\n", "422 Too busy to play with you.\r\n", "423 Connection timed out.\r\n", "215 UNIX Type: L8 (Linux).\r\n", "500 Unknown type.\r\n", "502 Illegal PORT request.\r\n", "200 PORT command successful.\r\n", "250 CWD command successful.\r\n", "553 Permission denied.\r\n", "350 Resume request successful.\r\n", "451 Transmition error occured.\r\n", "209 Received break, bye.\r\n", "503 Command not understood.\r\n", "227 Abort successful.\r\n", "591 Data transmition stopped by admin.\r\n", "491 Download in progress.\r\n", "257 MKD command successful.\r\n", "258 RMD command successful.\r\n", "259 File successfully deleted.\r\n" "540 User banned.\r\n", "540 User banned.\r\n", "550 not a file.\r\n", NULL }; /* prototypes */ void user_spool(int,int,char *); int checkpath(int,char *,char *); void childtimeout(int); int waitaccept(int); void do_list(int,char *,int); int do_chdir(int,char *); int do_retr(int,char *); int do_stor(int,char *); void do_user(int,char *); void do_pass(int,char *); void do_size(int,char *); void do_mdtm(int,char *); void do_pasv(int); int do_mkdir(int,char *); int do_rmdir(int,char *); int do_dele(int,char *); void user_return(int nr,int id) { /* printf("Sending '%s'\n",ftp_returnstr[id]); */ write(pchild[nr]->sock,ftp_returnstr[id],strlen(ftp_returnstr[id])); } void user_spool(int nr,int id,char *file) { char buffer[1024],marker[32]; FILE *fp; fd_set fds; struct timeval tv; int n; if (file[0]!=0) { if ((fp=fopen(file,"r"))!=NULL) { n=0; while (fgets(buffer,sizeof(buffer)-1,fp)!=NULL) { if (n==0) sprintf(marker,"%d- ",id); write(pchild[nr]->sock,marker,strlen(marker)); if ((n=strlen(buffer))>0) { if (buffer[n-1]=='\n') buffer[n-1]=0; strcat(buffer,"\r\n"); } do { FD_ZERO(&fds); FD_SET(pchild[nr]->sock,&fds); tv.tv_sec=transfertimeout;tv.tv_usec=0; if (select(pchild[nr]->sock+1,NULL,&fds,NULL,&tv)<=0) { #ifdef DEBUG fprintf(stderr,"Spool (%d) timeout to client %d.\n",id,nr+1); #endif kill_connection(nr); return; } } while (!FD_ISSET(pchild[nr]->sock,&fds)); write(pchild[nr]->sock,buffer,strlen(buffer)); } } } } int checkpath(int nr,char *param,char *path) { char cmd[MAXPATHLEN+4]; char allowed[MAXPATHLEN+4]; if (!strcmp(pchild[nr]->rootdir,"/")) { strcpy(allowed,pchild[nr]->rootdir); } else { /* should not happen */ if (strlen(pchild[nr]->rootdir)>=MAXPATHLEN) return 1; sprintf(allowed,"%s/",pchild[nr]->rootdir); } if (strlen(allowed)+strlen(pchild[nr]->reldir)>=sizeof(cmd)) return 1; sprintf(cmd,"%s%s",allowed,pchild[nr]->reldir); if (param) { if (param[0]!='/') { if (strlen(cmd)+strlen(param)>=sizeof(cmd)) return 1; strcat(cmd,param); } else { if (strlen(allowed)+strlen(&param[1])>=sizeof(cmd)) return 1; strcpy(cmd,allowed); strcat(cmd,&param[1]); } } #ifdef DEBUG fprintf(stderr,"Checking path %s\n",cmd); #endif if (!realpath(cmd,path)) return 1; #ifdef DEBUG fprintf(stderr,"Converted to: %s\n",path); #endif if (strlen(path)>=MAXPATHLEN) return 1; strcat(path,"/"); strcpy(cmd,path); cmd[strlen(allowed)]=0; #ifdef DEBUG printf("Comparing (%s) '%s'=='%s'\n", realchangeroot ? "real" : "virtual", cmd,allowed); #endif if (strcmp(cmd,allowed)) return 1; #ifdef DEBUG printf("Debug: path has now %d/%d chars.\n",strlen(path),MAXPATHLEN); #endif return 0; } void kill_connection(int nr) { char buffer[256]; time_t tm; if (!daemonmode) { printf("User %d, killed.\n",nr+1); out_prompt(); } /* close passive port */ if (pchild[nr]->pasvsock) { close(pchild[nr]->pasvsock); pchild[nr]->pasvsock=0; } /* checking retr subprocess */ if (pchild[nr]->pid) kill(pchild[nr]->pid,SIGTERM); pchild[nr]->pid=0; /* close connection and tidy up */ close(pchild[nr]->sock); pchild[nr]->sock=0; pchild[nr]->dataport=0; if (logfile!=NULL) { tm=time(NULL); strcpy(buffer,ctime(&tm)); buffer[strlen(buffer)-1]=0; fprintf(logfile,"%s: LOGOUT: user %d ",buffer,nr+1); if (pchild[nr]->usertype<logininfocount) fprintf(logfile,"%s ",pchild[nr]->username); else fprintf(logfile,"nologin "); fprintf(logfile,"%s (%d.%d.%d.%d)\n", pchild[nr]->url, pchild[nr]->userip[0],pchild[nr]->userip[1], pchild[nr]->userip[2],pchild[nr]->userip[3]); fflush(logfile); } } void childtimeout(int nr) { exit(0); } int waitaccept(int nr) { int socksize,soc; struct sockaddr_in sai; signal(SIGALRM,childtimeout); alarm(transfertimeout); socksize=sizeof(sai); soc=accept(pchild[nr]->pasvsock,(struct sockaddr *)&sai,&socksize); signal(SIGALRM,SIG_IGN); return soc; } int list_callback(int soc,int nr,char *line) { fd_set fds; struct timeval tv; do { FD_ZERO(&fds); FD_SET(soc,&fds); tv.tv_sec=transfertimeout;tv.tv_usec=0; if (select(soc+1,NULL,&fds,NULL,&tv)<=0) { #ifdef DEBUG fprintf(stderr,"LIST timeout to client %d.\n",nr+1); #endif close(soc); user_return(nr,RET_501); return 0; } } while (!FD_ISSET(soc,&fds)); write(soc,line,strlen(line)); return 1; } void do_list(int nr,char *param,int listtype) { struct hostent *hp; char cmd[1024],path[1024],mask[1024]/*,cwd[1024]*/; unsigned long addr; int soc,n; unsigned int socksize; struct sockaddr_in sai; char nullch[8]; char *cmask; strcpy(nullch,"."); if (pchild[nr]->pasvsock<=0 && pchild[nr]->dataport==0) { user_return(nr,RET_501); exit(0); } mask[0]=0; if (param) { while (param[0]=='-') { n=1; while (param[n]!=' ' && param[n]!=0) n++; if (param[n]==' ') param=&param[n+1]; else param=&param[n]; } strcpy(cmd,param); if (strrchr(cmd,'*') || strrchr(cmd,'?')) { if (strrchr(cmd,'/')) { strcpy(mask,strrchr(cmd,'/')+1); *strrchr(cmd,'/')=0; } else { strcpy(mask,cmd); cmd[0]=0; } } if (strrchr(cmd,'*') || strrchr(cmd,'?')) { user_return(nr,RET_501); exit(0); } } else { cmd[0]=0; param=nullch; } if (param[0]=='/') param++; if (param[0]=='/') { user_return(nr,RET_501); exit(0); } cmask=strrchr(mask,'/'); if (cmask!=NULL) { *cmask=0; cmask++; if (strlen(cmd)+strlen(mask)+2>sizeof(cmd)) { user_return(nr,RET_501); exit(0); } strcat(cmd,"/"); strcat(cmd,mask); strcpy(mask,cmask); } #ifdef DEBUG printf("path before: %s\n",cmd); #endif if (checkpath(nr,cmd,path) || !strncmp(mask,"..",2)) { user_retu