/**************************************************************** esh v1.0 eun.su.am *****************************************************************/ /**************************************************************** 1 This program is free software; you can redistribute it and/or modify 2 it under the terms of the GNU General Public License as published by 3 the Free Software Foundation; version 2 of the License. 4 5 This program is distributed in the hope that it will be useful, 6 but WITHOUT ANY WARRANTY; without even the implied warranty of 7 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 8 GNU General Public License for more details. *****************************************************************/ /**************************************************************** esh is a shell that allows only the execution of specific commands Example use: Linux: 1. Create the folder /etc/esh/esh1 2. Put esh to your /bin/ folder and rename it to esh1 3. Now create symlinks in /etc/esh/esh1 which files should be allowed run 4. For Example: ln -s /bin/cd /etc/esh/esh1 This will allow the command cd in the esh1 shell. Windows: 1. Create the folder All Users/Application Data/esh/esh1.exe 2. Put esh to your Applications folder (or somewhere you can run it from) and rename it to esh1 3. Now create shortcuts in All Users/Application Data/esh/esh1.exe which files should be allowed run 4. For Example: create to "cmd" as a shoutcut in All Users/Application Data/esh/esh1.exe This will allow the command cmd in the esh1 shell. Note: * You don't need to create shourtcuts to cd in the settings folder, a simple textfile is enough. The reason for this is that "cd" is handled internal. * make sure the users who use esh arent allowed to add new items to /etc/esh/ * To prevent script executions ./ is not allowed * in windows compile with these extralibs: Ws2_32.lib Advapi32.lib userenv.lib *****************************************************************/ #ifdef _WIN32 #define WIN32_LEAN_AND_MEAN #else #define _GNU_SOURCE #endif #include #include #include #include #ifdef _WIN32 #include #include #include #include #include #pragma warning(disable: 4996) #define _getch getch #define printw printf #define stdscr 0 typedef enum {false , true} bool; void getyx(int *y, int *x); void move(int y, int x); char *basename (char *path); #else #include #include #include #include #include #include // ncurses-dev #define _getch(fp) getch() #define stricmp strcasecmp #define _getcwd getcwd #endif #define MAX_PATH 260 #define MAX_CMD 1024 bool bexit; char curhost[255] = ""; char curuser[255] = ""; char curhome[MAX_PATH] = ""; char bindir[MAX_PATH]="."; int maxbinlen = 0; int promtlen = 0; char cmdbuf[MAX_CMD]; int cmd; char initcmd[MAX_CMD]; int curYpos; int curpos; int hist; int curhist; char **cmdHist; char *_substr(const char *pstr, int start, int numchars); void int_exit (void); void runcmd(char *cmd); void writeprompt(void); void clearline(void); void clearchar(int pos); void specialkey(int mode); void MovePos(int x); void addToHistory(char *s); void UpdatePos(void); void sighandler(int sig); void getbins(void); int listbins(char *s, int len); //void autocomplete(char s, int len); #ifndef _WIN32 void GetUserInfo(char *user, size_t usize, char *home, size_t hsize); #endif char **ext_cmd; int extcmdSize; int main(int argc, char *argv[]) { bool bnew; // write a new promt char c; int tab = 0; // 2 tabs = autocomplete int ctrla = 0; // ctrl+a and ctrl + d = exit #ifdef _WIN32 DWORD size; WSADATA wsaData; HANDLE hToken = 0; WSAStartup(MAKEWORD(1, 1), &wsaData); #endif gethostname(curhost, sizeof(curhost)); #ifdef _WIN32 size = sizeof(curuser); GetUserName(curuser, &size); size = sizeof(curhome); OpenProcessToken( GetCurrentProcess(), TOKEN_QUERY, &hToken ); GetUserProfileDirectory( hToken, curhome, &size ); CloseHandle( hToken ); #else GetUserInfo(curuser, sizeof(curuser), curhome, sizeof(curhome)); #endif // set bin dir #ifdef _WIN32 { TCHAR szPath[MAX_PATH]; if(SUCCEEDED(SHGetFolderPath(NULL, CSIDL_COMMON_APPDATA|CSIDL_FLAG_CREATE, NULL, 0, szPath))) { sprintf(bindir, "%s/esh/%s/",szPath, basename(argv[0])); } else { printf("Could not find config dir %s\n",bindir); return 0; } } #else sprintf(bindir, "/etc/esh/%s/", basename(argv[0])); #endif getbins(); signal(SIGABRT, &sighandler); signal(SIGTERM, &sighandler); #ifndef _WIN32 signal(SIGINT, &sighandler); initscr(); raw(); noecho(); //allow scrolling scrollok(stdscr, true); #endif // current console position // we need to use it otherwise make triggers error argc = 0; // curhist = 0; hist = 0; bexit = false; bnew = false; while (!bexit) { bnew = false; writeprompt(); memset(cmdbuf, 0, MAX_CMD); // init command? if (initcmd[0]) { strncpy(cmdbuf, initcmd, MAX_CMD); cmd = strlen(cmdbuf); printw(cmdbuf); memset(initcmd, 0, MAX_CMD); } else { cmd = 0; } UpdatePos(); c = 0; while (!bnew && c != EOF) { c = _getch(stdin); //printw("%d\n", c); // check single keystrokes if (c == 1) // CTRL +A { ctrla = 1; continue; } else // NO CTRL + A? RESET { ctrla = 0; } if (c == 3) // CTRL + C { int_exit(); bnew = true; continue; } else if (c == 4) // CTRL + D { if (ctrla == 1) // CTRL + A & CTRL + D pressed { int_exit(); bnew = true; } continue; } else if (c == 8) //BACKSPACE { specialkey(8); continue; } else if (c == 9) // TAB { if (tab == 1) // double TAB pressed { if (cmd == 0) { // list all bins we have if (listbins("", 0) == 0) { printw("\n"); } } else { // try to find a command, if its only one write it directly to console // if not put a list int ret = listbins(cmdbuf, cmd); if ( ret == 1) { // exactly one match? dont write a new prompt tab = 0; continue; } else if (ret > 1) { // more then one? // keep the cmd memset(initcmd, 0, MAX_CMD); strncpy(initcmd, cmdbuf, MAX_CMD); } else { // no match? dont write new prompt tab = 0; continue; } } tab = 0; bnew = true; } else { // just one tab was pressed tab = 1; } continue; } else // NO TAB? RESET { tab = 0; } #ifdef _WIN32 // trigger it later on linux if (c == 27) // ESC { // delete currentline clearline(); } #else if (c == 127) // DEL { specialkey(2); } #endif // check multi keystrokes #ifdef _WIN32 else if (c == -32) { // read the next char instantly c = _getch(stdin); // decide now if (c == 71) //POS1 { specialkey(0); continue; } else if (c == 79) //END { specialkey(1); continue; } else if (c == 83) //DEL { specialkey(2); continue; } else if (c == 72) // UP { specialkey(3); continue; } else if (c == 80) // DOWN { specialkey(4); continue; } else if (c == 77) //RIGHT { specialkey(6); continue; } else if (c == 75) // LEFT { specialkey(7); continue; } } #else else if (c == 27) { // read the next chars int j=0; char inbuf[4]=""; nodelay(stdscr, TRUE); while (1) { c = _getch(stdin); inbuf[j] = c; if (c == -1) break; if (inbuf[0] != 91 || j > 2) { // ignore j = -1; break; } j++; } nodelay(stdscr, FALSE); if (j == 0) // ESC { // delete currentline clearline(); } else if (j > 0) { // decide now if (inbuf[1] == 50 && inbuf[2] == 126) //POS1 { specialkey(0); c = 0; // set to 0 otherwise it will trigger the 27 continue; } else if (inbuf[1] == 52 && inbuf[2] == 126) // END { specialkey(1); c = 0; continue; } else if (inbuf[1] == 65) //UP { specialkey(3); c = 0; continue; } else if (inbuf[1] == 66) //DOWN { specialkey(4); c = 0; continue; } else if (inbuf[1] == 67) //RIGHT { specialkey(6); c = 0; continue; } else if (inbuf[1] == 68) //LEFT { specialkey(7); c = 0; continue; } } } #endif // return else if (c == '\n' || c == '\r') { printw("\n"); if (cmd > 0) { int i; bool bvalid=false; // exit commands if (!strncmp(cmdbuf, "exit", 4)) { // run command int_exit(); bnew = true; continue; } // open commands for (i = 0; i < extcmdSize; i++) { if (!strncmp(cmdbuf, ext_cmd[i], strlen(ext_cmd[i]))) { addToHistory(cmdbuf); //printw(">running %s\n",cmdbuf); runcmd(cmdbuf); bvalid = true; break; } } if(!bvalid) { addToHistory(cmdbuf); printw("esh: unknown command '%s'\n",cmdbuf); } } bnew = true; } // if its not a 'special' key: build cmdbuf else { if (cmd < MAX_CMD) { if (curpos == cmd) // cursor is on the end { strncat(cmdbuf, &c, 1); printw("%c",c); cmd++; UpdatePos(); } else if (curpos < cmd) // cursor is somewhere in the middle { char buf1[MAX_CMD]=""; char *buf2 = ""; char buf3[MAX_CMD]=""; int posback = curpos; // copy first part strncpy(buf1,cmdbuf, curpos); // copy second part buf2 = _substr(cmdbuf, curpos, cmd); // put it together sprintf(buf3, "%s%c%s", buf1, c, buf2); clearline(); strncpy(cmdbuf, buf3, strlen(buf3)); cmd = strlen(buf3); printw(cmdbuf); // move cursor to curpos MovePos(posback+1); free(buf2); } } } } } sighandler(0); return 0; } void int_exit (void) { bexit = true; } char *_substr(const char *pstr, int start, int numchars) { char *pnew = malloc(numchars+1); strncpy(pnew, pstr + start, numchars); pnew[numchars] = '\0'; return pnew; } void changedir(const char *path) { if (path[0] == '~') { char np[MAX_PATH] = ""; // build new path char *newpath = _substr(path, 1, strlen(path)); sprintf(np,"%s/%s",curhome, newpath); free(newpath); chdir(np); } else { chdir(path); } } void runcmd(char *cmd) { // cd can be disabled thats why its here if (!strncmp(cmd, "cd", 2)) { char *pch = strtok(cmd," "); if (pch) { pch = strtok(NULL, " "); if (pch) { changedir(pch); return; } } changedir("~"); return; } system(cmd); } // fill allowed commands to array void getbins(void) { #ifdef _WIN32 char sdir[MAX_PATH+1] = ""; int i=0; HANDLE hFind; WIN32_FIND_DATA FindData; extcmdSize = 0; ext_cmd = (char **) malloc(sizeof(char*) * 2); sprintf(sdir,"%s\\*", bindir); hFind = FindFirstFile(sdir, &FindData); if (hFind == INVALID_HANDLE_VALUE) return; if (strcmp(FindData.cFileName,".") && strcmp(FindData.cFileName,"..")) { maxbinlen = strlen(FindData.cFileName); i++; ext_cmd[0] = (char *) malloc(sizeof(char*) * (maxbinlen+1)); strncpy(ext_cmd[0], FindData.cFileName, maxbinlen); } while (FindNextFile(hFind, &FindData)) { if (FindData.dwFileAttributes != FILE_ATTRIBUTE_DIRECTORY) { int len = strlen(FindData.cFileName); if (len > maxbinlen) maxbinlen = len; ext_cmd = (char **) realloc(ext_cmd, sizeof(char*) * (i+1)); ext_cmd[i] = (char *) malloc(sizeof(char*) * len+1); strcpy(ext_cmd[i], FindData.cFileName); i++; } } FindClose(hFind); #else int i=0; DIR *pDir = opendir (bindir); struct dirent *pEntry; if ( !pDir) return; extcmdSize = 0; ext_cmd = (char **) malloc(sizeof(char*) * 2); pEntry = readdir (pDir); while ( pEntry ) { if (!(DT_DIR & pEntry->d_type)) { int len = strlen(pEntry->d_name); if (len > maxbinlen) maxbinlen = len; ext_cmd = (char **) realloc(ext_cmd, sizeof(char*) * (i+1)); ext_cmd[i] = (char *) malloc(sizeof(char*) * len+1); strcpy(ext_cmd[i], pEntry->d_name); i++; } pEntry = readdir (pDir); } closedir(pDir); #endif extcmdSize = i; } int listbins(char *s, int len) { // no commands? if (maxbinlen == 0) return 0; else { int i; int matches=0; int colums, clmstep = 0; char firstmatch[MAX_CMD]=""; #ifdef _WIN32 HANDLE hFind; WIN32_FIND_DATA FindData; CONSOLE_SCREEN_BUFFER_INFO csbiInfo; HANDLE hStdout = GetStdHandle(STD_OUTPUT_HANDLE); GetConsoleScreenBufferInfo(hStdout, &csbiInfo); // calculate colums colums = (unsigned int)csbiInfo.dwMaximumWindowSize.X / (maxbinlen + 2); #else colums = (unsigned int)COLS / (maxbinlen + 2); #endif if (colums == 0) colums = 1; if (len == 0) printw("\n"); for (i = 0; i < extcmdSize; i++) { if (len > 0) { if (!strncmp(ext_cmd[i], s, len)) { // save first match, this might be the one, if not we print it if (matches == 0) { strncpy(firstmatch, ext_cmd[i], MAX_CMD); } if (matches == 1) { printw("\n%-*s", maxbinlen+2, firstmatch); clmstep++; if (clmstep == colums) { printw("\n"); clmstep = 0; } printw("%-*s", maxbinlen+2, ext_cmd[i]); clmstep++; if (clmstep == colums) { printw("\n"); clmstep = 0; } } else if (matches > 1) { printw("%-*s", maxbinlen+2, ext_cmd[i]); clmstep++; } if (clmstep == colums) { printw("\n"); clmstep = 0; } matches++; } } else { printw("%-*s", maxbinlen+2, ext_cmd[i]); clmstep++; if (clmstep == colums) { printw("\n"); clmstep = 0; } } } if (clmstep > 0 && (matches > 1 || len == 0)) printw("\n"); if (matches == 1) { // delete the old stuff and write our clearline(); printw(firstmatch); strncpy(cmdbuf, firstmatch, MAX_CMD); cmd = strlen(firstmatch); } return matches; } } #ifndef _WIN32 void GetUserInfo(char *user, size_t usize, char *home, size_t hsize) { char *c; struct utmp *u; const struct passwd *pwd; c=getlogin(); setutent(); while((u=getutent())) { if(u->ut_type==7 && strcmp(u->ut_user,c)==0) { strncpy(user,u->ut_user, usize); break; } } while ((pwd = getpwent ())) { if (!stricmp (user, pwd->pw_name)) { strncpy(home,pwd->pw_dir, hsize); break; } } } #endif void writeprompt(void) { char curdir[MAX_PATH] = ""; _getcwd(curdir, MAX_PATH); printw("%s@%s:%s$ ", curuser, curhost, curdir); promtlen = strlen(curuser)+1+strlen(curhost)+1+strlen(curdir)+2; } void clearline(void) { int i; memset(cmdbuf, 0, MAX_CMD); // move cursor to beginning and clear all chars specialkey(0); for (i = 0; i < cmd; i++) printw(" "); // and back to beginning MovePos(0); cmd = 0; } void clearchar(int pos) { // abcdef // abcef // copy the first part char buf1[MAX_CMD]=""; char *buf2 = ""; char buf3[MAX_CMD]=""; // copy first part strncpy(buf1,cmdbuf, pos-1); // copy second part buf2 = _substr(cmdbuf, pos, cmd); // put it together sprintf(buf3, "%s%s", buf1, buf2); clearline(); strncpy(cmdbuf, buf3, strlen(buf3)); cmd = strlen(buf3); printw(cmdbuf); free(buf2); } void specialkey(int mode) { UpdatePos(); if (mode == 0) // POS1 was pressed { if (curpos > 0) { MovePos(0); } } else if (mode == 1) // END was pressed { if (curpos < cmd) { MovePos(cmd); } } else if (mode == 2) // DEL was pressed { if (curpos < cmd) { // delete next char // save the position because clearchar calls clearline, // and clearline sets pos to 0 int posbak = curpos; clearchar(curpos+1); MovePos(posbak); } } else if (mode == 3) // UP was pressed { if (hist > 0 && curhist < hist) { clearline(); strncpy(cmdbuf, cmdHist[hist-curhist-1], MAX_CMD); printw(cmdbuf); cmd = strlen(cmdbuf); MovePos(cmd); curhist++; } } else if (mode == 4) // DOWN was pressed { if (hist > 0 && curhist > 1) { clearline(); strncpy(cmdbuf, cmdHist[hist-curhist+1], MAX_CMD); printw(cmdbuf); cmd = strlen(cmdbuf); MovePos(cmd); curhist--; } } else if (mode == 6) // RIGHT was pressed { if (curpos < cmd) { MovePos(curpos+1); } } else if (mode == 7) // LEFT was pressed { if (curpos > 0) { MovePos(curpos-1); } } else if (mode == 8) // BACKSPACE was pressed { if (curpos > 0) { // delete previous char if (cmd > 0) { // we are on end if (cmd == curpos) { cmd--; cmdbuf[cmd] = 0; printw("\b \b"); MovePos(curpos-1); } // we are somewhere on the middle else if (cmd > curpos) { // save the position because clearchar calls clearline, // and clearline sets pos to 0 int posbak = curpos; clearchar(curpos); MovePos(posbak - 1); } } } } return; } #ifdef _WIN32 void getyx(int *y, int *x) { CONSOLE_SCREEN_BUFFER_INFO csbi; *x = *y = 0; if(GetConsoleScreenBufferInfo(GetStdHandle(STD_OUTPUT_HANDLE), &csbi)) { *x = csbi.dwCursorPosition.X; *y = csbi.dwCursorPosition.Y; } } void move( int y, int x ) { HANDLE hStdout = GetStdHandle(STD_OUTPUT_HANDLE); COORD position = {x, y}; SetConsoleCursorPosition(hStdout, position); } #endif void UpdatePos(void) { int y,x; #ifdef _WIN32 getyx(&y, &x); #else getyx(stdscr, y, x); #endif curYpos = y; curpos = x-promtlen; } void MovePos(int x) { move(curYpos, promtlen + x); curpos = x; } void addToHistory(char *s) { if (hist == 0) { cmdHist = (char**)malloc(sizeof(char*) * 2); } else { cmdHist = (char**)realloc(cmdHist, sizeof(char*) * (hist+1)); } cmdHist[hist] = (char*)malloc(sizeof(char*) * strlen(s) + 1); strcpy(cmdHist[hist], s); hist++; curhist = 0; } #ifdef _WIN32 char *basename (char *path) { char *ret = strrchr (path, '\\'); return ret ? ++ret : (char*)path; } #endif void sighandler( int sig ) { int i; for (i = 0; i < extcmdSize; i++) { free(ext_cmd[i]); } free(ext_cmd); for (i = 0; i < hist; i++) { free(cmdHist[i]); } free(cmdHist); #ifndef _WIN32 refresh(); endwin(); #else system("pause"); #endif exit(sig); }