/* Copyright (c) 2008, 2009 * Juergen Weigert (jnweiger@immd4.informatik.uni-erlangen.de) * Michael Schroeder (mlschroe@immd4.informatik.uni-erlangen.de) * Micah Cowan (micah@cowan.name) * Sadrul Habib Chowdhury (sadrul@users.sourceforge.net) * Copyright (c) 1993-2002, 2003, 2005, 2006, 2007 * Juergen Weigert (jnweiger@immd4.informatik.uni-erlangen.de) * Michael Schroeder (mlschroe@immd4.informatik.uni-erlangen.de) * Copyright (c) 1987 Oliver Laumann * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program (see the file COPYING); if not, see * http://www.gnu.org/licenses/, or contact Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02111-1301 USA * **************************************************************** */ #include "config.h" #include "fileio.h" #include #include #include #include #include #include #include #include "screen.h" #include "misc.h" #include "process.h" #include "termcap.h" #include "encoding.h" static char *CatExtra(char *, char *); static char *findrcfile(char *); char *rc_name = ""; int rc_recursion = 0; static char *CatExtra(char *str1, char *str2) { char *cp; size_t len1, len2; bool add_colon; len1 = strlen(str1); if (len1 == 0) return str2; add_colon = (str1[len1 - 1] != ':'); if (str2) { len2 = strlen(str2); if ((cp = realloc(str2, len1 + len2 + add_colon + 1)) == NULL) Panic(0, "%s", strnomem); memmove(cp + len1 + add_colon, cp, len2 + 1); } else { if ((cp = malloc(len1 + add_colon + 1)) == NULL) Panic(0, "%s", strnomem); cp[len1 + add_colon] = '\0'; } memmove(cp, str1, len1); if (add_colon) cp[len1] = ':'; return cp; } static char *findrcfile(char *rcfile) { char buf[256]; char *p; /* Tilde prefix support courtesy , * taken from a Debian patch. */ if (rcfile && *rcfile == '~') { static char rcfilename_tilde_exp[MAXPATHLEN + 1]; char *slash_position = strchr(rcfile, '/'); if (slash_position == rcfile + 1) { if (!home) { Msg(0, "%s: source: tilde expansion failed", rc_name); return NULL; } snprintf(rcfilename_tilde_exp, MAXPATHLEN, "%s/%s", home, rcfile + 2); } else if (slash_position) { struct passwd *p; *slash_position = 0; p = getpwnam(rcfile + 1); if (!p) { Msg(0, "%s: source: tilde expansion failed for user %s", rc_name, rcfile + 1); return NULL; } snprintf(rcfilename_tilde_exp, MAXPATHLEN, "%s/%s", p->pw_dir, slash_position + 1); } else { Msg(0, "%s: source: illegal tilde expression.", rc_name); return NULL; } rcfile = rcfilename_tilde_exp; } if (rcfile) { char *rcend = strrchr(rc_name, '/'); if (*rcfile != '/' && rcend && (rcend - rc_name) + strlen(rcfile) + 2 < ARRAY_SIZE(buf)) { strncpy(buf, rc_name, rcend - rc_name + 1); strncpy(buf + (rcend - rc_name) + 1, rcfile, 256 - (rcend - rc_name)); if (access(buf, R_OK) == 0) return SaveStr(buf); } return SaveStr(rcfile); } if ((p = getenv("SCREENRC")) != NULL && *p != '\0') { return SaveStr(p); } else { if (strlen(home) > ARRAY_SIZE(buf) - 12) Panic(0, "Rc: home too large"); sprintf(buf, "%s/.screenrc", home); return SaveStr(buf); } } /* * this will be called twice: * 1) rcfilename = "/etc/screenrc" * 2) rcfilename = RcFileName */ int StartRc(char *rcfilename, int nopanic) { int argc, len; char *p, *cp; char buf[2048]; char *args[MAXARGS]; int argl[MAXARGS]; FILE *fp; char *oldrc_name = rc_name; /* always fix termcap/info capabilities */ extra_incap = CatExtra("TF", extra_incap); /* Special settings for vt100 and others */ if (display && (!strncmp(D_termname, "vt", 2) || !strncmp(D_termname, "xterm", 5))) extra_incap = CatExtra ("xn:f0=\033Op:f1=\033Oq:f2=\033Or:f3=\033Os:f4=\033Ot:f5=\033Ou:f6=\033Ov:f7=\033Ow:f8=\033Ox:f9=\033Oy:f.=\033On:f,=\033Ol:fe=\033OM:f+=\033Ok:f-=\033Om:f*=\033Oj:f/=\033Oo:fq=\033OX", extra_incap); rc_name = findrcfile(rcfilename); if (rc_name == NULL || (fp = secfopen(rc_name, "r")) == NULL) { const char *rc_nonnull = rc_name ? rc_name : rcfilename; if (!rc_recursion && RcFileName && !strcmp(RcFileName, rc_nonnull)) { /* * User explicitly gave us that name, * this is the only case, where we get angry, if we can't read * the file. */ if (!nopanic) Panic(0, "Unable to open \"%s\".", rc_nonnull); /* possibly NOTREACHED */ } if (rc_name) Free(rc_name); rc_name = oldrc_name; return 1; } while (fgets(buf, ARRAY_SIZE(buf), fp) != NULL) { if ((p = strrchr(buf, '\n')) != NULL) *p = '\0'; if ((argc = Parse(buf, ARRAY_SIZE(buf), args, argl)) == 0) continue; if (strcmp(args[0], "echo") == 0) { if (!display) continue; if (argc < 2 || (argc == 3 && strcmp(args[1], "-n")) || argc > 3) { Msg(0, "%s: 'echo [-n] \"string\"' expected.", rc_name); continue; } AddStr(args[argc - 1]); if (argc != 3) { AddStr("\r\n"); Flush(0); } } else if (strcmp(args[0], "sleep") == 0) { if (!display) continue; if (argc != 2) { Msg(0, "%s: sleep: one numeric argument expected.", rc_name); continue; } DisplaySleep1000(1000 * atoi(args[1]), 1); } else if (!strcmp(args[0], "termcapinfo") || !strcmp(args[0], "terminfo")) { if (!display) continue; if (argc < 3 || argc > 4) { Msg(0, "%s: %s: incorrect number of arguments.", rc_name, args[0]); continue; } for (p = args[1]; p && *p; p = cp) { if ((cp = strchr(p, '|')) != NULL) *cp++ = '\0'; len = strlen(p); if (p[len - 1] == '*') { if (!(len - 1) || !strncmp(p, D_termname, len - 1)) break; } else if (!strcmp(p, D_termname)) break; } if (!(p && *p)) continue; extra_incap = CatExtra(args[2], extra_incap); if (argc == 4) extra_outcap = CatExtra(args[3], extra_outcap); } else if (!strcmp(args[0], "source")) { if (rc_recursion <= 10) { rc_recursion++; (void)StartRc(args[1], 0); rc_recursion--; } } } fclose(fp); Free(rc_name); rc_name = oldrc_name; return 0; } void FinishRc(char *rcfilename) { char buf[2048]; FILE *fp; char *oldrc_name = rc_name; rc_name = findrcfile(rcfilename); if (rc_name == NULL || (fp = secfopen(rc_name, "r")) == NULL) { const char *rc_nonnull = rc_name ? rc_name : rcfilename; if (rc_recursion) Msg(errno, "%s: source %s", oldrc_name, rc_nonnull); else if (RcFileName && !strcmp(RcFileName, rc_nonnull)) { /* * User explicitly gave us that name, * this is the only case, where we get angry, if we can't read * the file. */ Panic(0, "Unable to open \"%s\".", rc_nonnull); /* NOTREACHED */ } if (rc_name) Free(rc_name); rc_name = oldrc_name; return; } while (fgets(buf, ARRAY_SIZE(buf), fp) != NULL) RcLine(buf, ARRAY_SIZE(buf)); (void)fclose(fp); Free(rc_name); rc_name = oldrc_name; } void do_source(char *rcfilename) { if (rc_recursion > 10) { Msg(0, "%s: source: recursion limit reached", rc_name); return; } rc_recursion++; FinishRc(rcfilename); rc_recursion--; } /* * Running a Command Line in the environment determined by the display. * The fore window is taken from the display as well as the user. * This is bad when we run detached. */ void RcLine(char *ubuf, int ubufl) { char *args[MAXARGS]; int argl[MAXARGS]; if (display) { fore = D_fore; flayer = D_forecv->c_layer; } else flayer = fore ? fore->w_savelayer : NULL; if (Parse(ubuf, ubufl, args, argl) <= 0) return; if (!display) { /* the session owner does it, when there is no display here */ EffectiveAclUser = users; } DoCommand(args, argl); EffectiveAclUser = NULL; } static void putc_encoded(FILE *f, uint32_t c, uint32_t font, int encoding) { /* Filler character which is used for double-width characters. */ if (c == 0xff && font == 0xff) return; char buf[10]; int length = EncodeChar(buf, c, encoding, NULL); if (length < 0) { return; } buf[length] = 0; fputs(buf, f); } /* * needs display for copybuffer access and termcap dumping */ void WriteFile(struct acluser *user, char *fn, int dump) { /* dump==0: create .termcap, * dump==1: hardcopy, * dump==2: BUFFERFILE * dump==1: scrollback, */ int i, j, k; char *c; FILE *f; char fnbuf[FILENAME_MAX]; char *mode = "w"; int public = 0; struct stat stb, stb2; int fd, exists = 0; switch (dump) { case DUMP_TERMCAP: if (fn == NULL) { i = SocketName - SocketPath; if (i > (int)ARRAY_SIZE(fnbuf) - 9) i = 0; strncpy(fnbuf, SocketPath, i); strncpy(fnbuf + i, ".termcap", 9); fn = fnbuf; } break; case DUMP_HARDCOPY: case DUMP_SCROLLBACK: if (fn == NULL) { if (fore == NULL) return; if (hardcopydir && *hardcopydir && strlen(hardcopydir) < ARRAY_SIZE(fnbuf) - 21) sprintf(fnbuf, "%s/hardcopy.%d", hardcopydir, fore->w_number); else sprintf(fnbuf, "hardcopy.%d", fore->w_number); fn = fnbuf; } if (hardcopy_append && !access(fn, W_OK)) mode = "a"; break; case DUMP_EXCHANGE: if (fn == NULL) { strncpy(fnbuf, BufferFile, ARRAY_SIZE(fnbuf) - 1); fnbuf[ARRAY_SIZE(fnbuf) - 1] = 0; fn = fnbuf; } public = !strcmp(fn, DEFAULT_BUFFERFILE); exists = !lstat(fn, &stb); if (public && exists && (S_ISLNK(stb.st_mode) || stb.st_nlink > 1)) { Msg(0, "No write to links, please."); return; } break; } if (UserContext() > 0) { if (dump == DUMP_EXCHANGE && public) { if (exists) { if ((fd = open(fn, O_WRONLY, 0666)) >= 0) { if (fstat(fd, &stb2) == 0 && stb.st_dev == stb2.st_dev && stb.st_ino == stb2.st_ino) { if (ftruncate(fd, 0) != 0) { close(fd); fd = -1; } } else { close(fd); fd = -1; } } } else fd = open(fn, O_WRONLY | O_CREAT | O_EXCL, 0666); f = fd >= 0 ? fdopen(fd, mode) : NULL; } else f = fopen(fn, mode); if (f == NULL) { UserReturn(0); } else { uint32_t *p, *pf; switch (dump) { case DUMP_HARDCOPY: case DUMP_SCROLLBACK: if (!fore) break; if (*mode == 'a') { putc('>', f); for (j = fore->w_width - 2; j > 0; j--) putc('=', f); fputs("<\n", f); } if (dump == DUMP_SCROLLBACK) { for (i = fore->w_histheight - fore->w_scrollback_height; i < fore->w_histheight; i++) { p = (WIN(i)->image); pf = WIN(i)->font; for (k = fore->w_width - 1; k >= 0 && p[k] == ' '; k--) ; for (j = 0; j <= k; j++) putc_encoded(f, p[j], pf[j], fore->w_encoding); putc('\n', f); } } for (i = 0; i < fore->w_height; i++) { p = fore->w_mlines[i].image; pf = fore->w_mlines[i].font; for (k = fore->w_width - 1; k >= 0 && p[k] == ' '; k--) ; for (j = 0; j <= k; j++) putc_encoded(f, p[j], pf[j], fore->w_encoding); putc('\n', f); } break; case DUMP_TERMCAP: if ((c = strchr(MakeTermcap(fore->w_aflag), '=')) != NULL) { fputs(++c, f); putc('\n', f); } break; case DUMP_EXCHANGE: c = user->u_plop.buf; for (i = user->u_plop.len; i-- > 0; c++) if (*c == '\r' && (i == 0 || c[1] != '\n')) putc('\n', f); else putc(*c, f); break; } (void)fclose(f); UserReturn(1); } } if (UserStatus() <= 0) Msg(0, "Cannot open \"%s\"", fn); else if (display && !*rc_name) { switch (dump) { case DUMP_TERMCAP: Msg(0, "Termcap entry written to \"%s\".", fn); break; case DUMP_HARDCOPY: case DUMP_SCROLLBACK: Msg(0, "Screen image %s to \"%s\".", (*mode == 'a') ? "appended" : "written", fn); break; case DUMP_EXCHANGE: Msg(0, "Copybuffer written to \"%s\".", fn); } } } /* * returns an allocated buffer which holds a copy of the file named filename. * lenp (if nonzero) points to a location, where the buffer size should be * stored. */ char *ReadFile(char *filename, int *lenp) { FILE *file; int l, size; char *buf = NULL; if ((file = secfopen(filename, "r")) == NULL) { Msg(errno, "no %s -- no slurp", filename); return NULL; } fseek(file, 0L, SEEK_END); size = ftell(file); if ((buf = malloc(size)) == NULL) { fclose(file); Msg(0, "%s", strnomem); return NULL; } fseek(file, 0L, SEEK_SET); errno = 0; if ((l = fread(buf, sizeof(char), size, file)) != size) { Msg(errno, "Got only %d bytes from %s", l, filename); } fclose(file); *lenp = l; return buf; } void KillBuffers(void) { if (UserContext() > 0) UserReturn(unlink(BufferFile) ? errno : 0); errno = UserStatus(); Msg(errno, "%s %sremoved", BufferFile, errno ? "not " : ""); } /* * (Almost) secure open and fopen... */ FILE *secfopen(char *name, char *mode) { FILE *fi; xseteuid(real_uid); xsetegid(real_gid); fi = fopen(name, mode); xseteuid(eff_uid); xsetegid(eff_gid); return fi; } int secopen(char *name, int flags, int mode) { int fd; xseteuid(real_uid); xsetegid(real_gid); fd = open(name, flags, mode); xseteuid(eff_uid); xsetegid(eff_gid); return fd; } int printpipe(Window *p, char *cmd) { int pi[2]; if (pipe(pi)) { WMsg(p, errno, "printing pipe"); return -1; } switch (fork()) { case -1: WMsg(p, errno, "printing fork"); return -1; case 0: display = p->w_pdisplay; displays = NULL; close(0); if (dup(pi[0]) < 0) Panic(errno, "printpipe dup"); closeallfiles(0); if (setgid(real_gid) || setuid(real_uid)) Panic(errno, "printpipe setuid"); #ifdef SIGPIPE xsignal(SIGPIPE, SIG_DFL); #endif execl("/bin/sh", "sh", "-c", cmd, NULL); Panic(errno, "/bin/sh"); default: break; } close(pi[0]); return pi[1]; } int readpipe(char **cmdv) { int pi[2]; if (pipe(pi)) { Msg(errno, "pipe"); return -1; } switch (fork()) { case -1: Msg(errno, "fork"); return -1; case 0: displays = NULL; close(1); if (dup(pi[1]) != 1) { close(pi[1]); Panic(0, "dup"); } closeallfiles(1); if (setgid(real_gid) || setuid(real_uid)) { close(1); Panic(errno, "setuid/setgid"); } execvp(*cmdv, cmdv); close(1); Panic(errno, "%s", *cmdv); default: break; } close(pi[1]); return pi[0]; }