X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=sudo_edit.c;h=f8666d9555b80a0d075d622b9c4325e682d649ec;hb=6ba437d0a1f717a93efa4e3a42fd9ddd8144a286;hp=fba5a1b945cf4eb87ea0ca75e38bfa72edf477f8;hpb=812709a155f4e8ca2a6b6070bad027a372835857;p=debian%2Fsudo diff --git a/sudo_edit.c b/sudo_edit.c index fba5a1b..f8666d9 100644 --- a/sudo_edit.c +++ b/sudo_edit.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2004-2008 Todd C. Miller + * Copyright (c) 2004-2008, 2010 Todd C. Miller * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above @@ -16,6 +16,8 @@ #include +#if defined(HAVE_SETRESUID) || defined(HAVE_SETREUID) || defined(HAVE_SETEUID) + #include #include #include @@ -33,15 +35,15 @@ #endif /* STDC_HEADERS */ #ifdef HAVE_STRING_H # include -#else -# ifdef HAVE_STRINGS_H -# include -# endif #endif /* HAVE_STRING_H */ +#ifdef HAVE_STRINGS_H +# include +#endif /* HAVE_STRINGS_H */ #ifdef HAVE_UNISTD_H # include #endif /* HAVE_UNISTD_H */ #include +#include #include #include #include @@ -49,20 +51,12 @@ #if TIME_WITH_SYS_TIME # include #endif -#ifndef HAVE_TIMESPEC -# include -#endif #include "sudo.h" -#ifndef lint -__unused static const char rcsid[] = "$Sudo: sudo_edit.c,v 1.37 2008/11/09 14:13:12 millert Exp $"; -#endif /* lint */ - -extern sigaction_t saved_sa_int, saved_sa_quit, saved_sa_tstp; -extern char **environ; +static char *find_editor __P((int *argc_out, char ***argv_out)); -static char *find_editor(); +extern char **NewArgv; /* XXX */ /* * Wrapper to allow users to edit privileged files with their own uid. @@ -70,24 +64,30 @@ static char *find_editor(); int sudo_edit(argc, argv, envp) int argc; - char **argv; - char **envp; + char *argv[]; + char *envp[]; { ssize_t nread, nwritten; - pid_t kidpid, pid; const char *tmpdir; - char **nargv, **ap, *editor, *cp; + char *cp, *suff, **nargv, *editor, **files; + char **editor_argv = NULL; char buf[BUFSIZ]; - int error, i, ac, ofd, tfd, nargc, rval, tmplen, wasblank; + int rc, i, j, ac, ofd, tfd, nargc, rval, nfiles, tmplen; + int editor_argc = 0; struct stat sb; - struct timespec ts1, ts2; + struct timeval tv, tv1, tv2; struct tempfile { char *tfile; char *ofile; - struct timespec omtim; + struct timeval omtim; off_t osize; } *tf; + /* Determine user's editor. */ + editor = find_editor(&editor_argc, &editor_argv); + if (editor == NULL) + return 1; + /* * Find our temporary directory, one of /var/tmp, /usr/tmp, or /tmp */ @@ -103,182 +103,129 @@ sudo_edit(argc, argv, envp) while (tmplen > 0 && tmpdir[tmplen - 1] == '/') tmplen--; - /* - * Close password, shadow, and group files before we try to open - * user-specified files to prevent the opening of things like /dev/fd/4 - */ - sudo_endpwent(); - sudo_endgrent(); - /* * For each file specified by the user, make a temporary version * and copy the contents of the original to it. */ - tf = emalloc2(argc - 1, sizeof(*tf)); - zero_bytes(tf, (argc - 1) * sizeof(*tf)); - for (i = 0, ap = argv + 1; i < argc - 1 && *ap != NULL; i++, ap++) { - error = -1; + files = argv + 1; + nfiles = argc - 1; + tf = emalloc2(nfiles, sizeof(*tf)); + zero_bytes(tf, nfiles * sizeof(*tf)); + for (i = 0, j = 0; i < nfiles; i++) { + rc = -1; set_perms(PERM_RUNAS); - if ((ofd = open(*ap, O_RDONLY, 0644)) != -1 || errno == ENOENT) { + if ((ofd = open(files[i], O_RDONLY, 0644)) != -1 || errno == ENOENT) { if (ofd == -1) { zero_bytes(&sb, sizeof(sb)); /* new file */ - error = 0; + rc = 0; } else { #ifdef HAVE_FSTAT - error = fstat(ofd, &sb); + rc = fstat(ofd, &sb); #else - error = stat(tf[i].ofile, &sb); + rc = stat(tf[j].ofile, &sb); #endif } } set_perms(PERM_ROOT); - if (error || (ofd != -1 && !S_ISREG(sb.st_mode))) { - if (error) - warning("%s", *ap); + if (rc || (ofd != -1 && !S_ISREG(sb.st_mode))) { + if (rc) + warning("%s", files[i]); else - warningx("%s: not a regular file", *ap); + warningx("%s: not a regular file", files[i]); if (ofd != -1) close(ofd); - argc--; - i--; continue; } - tf[i].ofile = *ap; - tf[i].omtim.tv_sec = mtim_getsec(sb); - tf[i].omtim.tv_nsec = mtim_getnsec(sb); - tf[i].osize = sb.st_size; - if ((cp = strrchr(tf[i].ofile, '/')) != NULL) + tf[j].ofile = files[i]; + tf[j].osize = sb.st_size; + mtim_get(&sb, &tf[j].omtim); + if ((cp = strrchr(tf[j].ofile, '/')) != NULL) cp++; else - cp = tf[i].ofile; - easprintf(&tf[i].tfile, "%.*s/%s.XXXXXXXX", tmplen, tmpdir, cp); + cp = tf[j].ofile; + suff = strrchr(cp, '.'); + if (suff != NULL) { + easprintf(&tf[j].tfile, "%.*s/%.*sXXXXXXXX%s", tmplen, tmpdir, (int)(size_t)(suff - cp), cp, suff); + } else { + easprintf(&tf[j].tfile, "%.*s/%s.XXXXXXXX", tmplen, tmpdir, cp); + } set_perms(PERM_USER); - tfd = mkstemp(tf[i].tfile); + tfd = mkstemps(tf[j].tfile, suff ? strlen(suff) : 0); set_perms(PERM_ROOT); if (tfd == -1) { - warning("mkstemp"); + warning("mkstemps"); goto cleanup; } if (ofd != -1) { while ((nread = read(ofd, buf, sizeof(buf))) != 0) { if ((nwritten = write(tfd, buf, nread)) != nread) { if (nwritten == -1) - warning("%s", tf[i].tfile); + warning("%s", tf[j].tfile); else - warningx("%s: short write", tf[i].tfile); + warningx("%s: short write", tf[j].tfile); goto cleanup; } } close(ofd); } -#ifdef HAVE_FSTAT /* - * If we are unable to set the mtime on the temp file to the value - * of the original file just make the stashed mtime match the temp - * file's mtime. It is better than nothing and we only use the info + * We always update the stashed mtime because the time + * resolution of the filesystem the temporary file is on may + * not match that of the filesystem where the file to be edited + * resides. It is OK if touch() fails since we only use the info * to determine whether or not a file has been modified. */ - if (touch(tfd, NULL, &tf[i].omtim) == -1) { - if (fstat(tfd, &sb) == 0) { - tf[i].omtim.tv_sec = mtim_getsec(sb); - tf[i].omtim.tv_nsec = mtim_getnsec(sb); - } - /* XXX - else error? */ - } + (void) touch(tfd, NULL, &tf[j].omtim); +#ifdef HAVE_FSTAT + rc = fstat(tfd, &sb); +#else + rc = stat(tf[j].tfile, &sb); #endif + if (!rc) + mtim_get(&sb, &tf[j].omtim); close(tfd); + j++; } - if (argc == 1) - return(1); /* no files readable, you lose */ - - environ = envp; - editor = find_editor(); + if ((nfiles = j) == 0) + return 1; /* no files readable, you lose */ /* * Allocate space for the new argument vector and fill it in. - * The EDITOR and VISUAL environment variables may contain command - * line args so look for those and alloc space for them too. + * We concatenate the editor with its args and the file list + * to create a new argv. + * We allocate an extra slot to be used if execve() fails. */ - nargc = argc; - for (wasblank = FALSE, cp = editor; *cp != '\0'; cp++) { - if (isblank((unsigned char) *cp)) - wasblank = TRUE; - else if (wasblank) { - wasblank = FALSE; - nargc++; - } - } - nargv = (char **) emalloc2(nargc + 1, sizeof(char *)); - ac = 0; - for ((cp = strtok(editor, " \t")); cp != NULL; (cp = strtok(NULL, " \t"))) - nargv[ac++] = cp; - for (i = 0; i < argc - 1 && ac < nargc; ) + nargc = editor_argc + nfiles; + nargv = (char **) emalloc2(1 + nargc + 1, sizeof(char *)); + nargv++; + for (ac = 0; ac < editor_argc; ac++) + nargv[ac] = editor_argv[ac]; + for (i = 0; i < nfiles && ac < nargc; ) nargv[ac++] = tf[i++].tfile; nargv[ac] = NULL; - /* Allow the editor to be suspended. */ - (void) sigaction(SIGTSTP, &saved_sa_tstp, NULL); - /* - * Fork and exec the editor with the invoking user's creds, + * Run the editor with the invoking user's creds, * keeping track of the time spent in the editor. */ - gettime(&ts1); - kidpid = fork(); - if (kidpid == -1) { - warning("fork"); - goto cleanup; - } else if (kidpid == 0) { - /* child */ - (void) sigaction(SIGINT, &saved_sa_int, NULL); - (void) sigaction(SIGQUIT, &saved_sa_quit, NULL); - set_perms(PERM_FULL_USER); - closefrom(def_closefrom + 1); - execvp(nargv[0], nargv); - warning("unable to execute %s", nargv[0]); - _exit(127); - } - - /* - * Wait for status from the child. Most modern kernels - * will not let an unprivileged child process send a - * signal to its privileged parent so we have to request - * status when the child is stopped and then send the - * same signal to our own pid. - */ - do { -#ifdef sudo_waitpid - pid = sudo_waitpid(kidpid, &i, WUNTRACED); -#else - pid = wait(&i); -#endif - if (pid == kidpid) { - if (WIFSTOPPED(i)) - kill(getpid(), WSTOPSIG(i)); - else - break; - } - } while (pid != -1 || errno == EINTR); - gettime(&ts2); - if (pid == -1 || !WIFEXITED(i)) - rval = 1; - else - rval = WEXITSTATUS(i); + gettime(&tv1); + rval = run_command(editor, nargv, envp, user_uid, TRUE); + gettime(&tv2); /* Copy contents of temp files to real ones */ - for (i = 0; i < argc - 1; i++) { - error = -1; + for (i = 0; i < nfiles; i++) { + rc = -1; set_perms(PERM_USER); if ((tfd = open(tf[i].tfile, O_RDONLY, 0644)) != -1) { #ifdef HAVE_FSTAT - error = fstat(tfd, &sb); + rc = fstat(tfd, &sb); #else - error = stat(tf[i].tfile, &sb); + rc = stat(tf[i].tfile, &sb); #endif } set_perms(PERM_ROOT); - if (error || !S_ISREG(sb.st_mode)) { - if (error) + if (rc || !S_ISREG(sb.st_mode)) { + if (rc) warning("%s", tf[i].tfile); else warningx("%s: not a regular file", tf[i].tfile); @@ -287,18 +234,14 @@ sudo_edit(argc, argv, envp) close(tfd); continue; } - if (tf[i].osize == sb.st_size && tf[i].omtim.tv_sec == mtim_getsec(sb) - && tf[i].omtim.tv_nsec == mtim_getnsec(sb)) { + mtim_get(&sb, &tv); + if (tf[i].osize == sb.st_size && timevalcmp(&tf[i].omtim, &tv, ==)) { /* * If mtime and size match but the user spent no measurable * time in the editor we can't tell if the file was changed. */ -#ifdef HAVE_TIMESPECSUB2 - timespecsub(&ts1, &ts2); -#else - timespecsub(&ts1, &ts2, &ts2); -#endif - if (timespecisset(&ts2)) { + timevalsub(&tv1, &tv2); + if (timevalisset(&tv2)) { warningx("%s unchanged", tf[i].ofile); unlink(tf[i].tfile); close(tfd); @@ -336,49 +279,118 @@ sudo_edit(argc, argv, envp) close(ofd); } - return(rval); + return rval; cleanup: /* Clean up temp files and return. */ - for (i = 0; i < argc - 1; i++) { + for (i = 0; i < nfiles; i++) { if (tf[i].tfile != NULL) unlink(tf[i].tfile); } - return(1); + return 1; +} + +static char * +resolve_editor(editor, argc_out, argv_out) + char *editor; + int *argc_out; + char ***argv_out; +{ + char *cp, **nargv, *editor_path = NULL; + int ac, nargc, wasblank; + + editor = estrdup(editor); /* becomes part of argv_out */ + + /* + * Split editor into an argument vector; editor is reused (do not free). + * The EDITOR and VISUAL environment variables may contain command + * line args so look for those and alloc space for them too. + */ + nargc = 1; + for (wasblank = FALSE, cp = editor; *cp != '\0'; cp++) { + if (isblank((unsigned char) *cp)) + wasblank = TRUE; + else if (wasblank) { + wasblank = FALSE; + nargc++; + } + } + /* If we can't find the editor in the user's PATH, give up. */ + cp = strtok(editor, " \t"); + if (cp == NULL || + find_path(cp, &editor_path, NULL, getenv("PATH"), 0) != FOUND) { + efree(editor); + return NULL; + } + nargv = (char **) emalloc2(nargc + 1, sizeof(char *)); + for (ac = 0; cp != NULL && ac < nargc; ac++) { + nargv[ac] = cp; + cp = strtok(NULL, " \t"); + } + nargv[ac] = NULL; + + *argc_out = nargc; + *argv_out = nargv; + return editor_path; } /* - * Determine which editor to use. We don't bother restricting this - * based on def_env_editor or def_editor since the editor runs with - * the uid of the invoking user, not the runas (privileged) user. + * Determine which editor to use. We don't need to worry about restricting + * this to a "safe" editor since it runs with the uid of the invoking user, + * not the runas (privileged) user. + * Fills in argv_out with an argument vector suitable for execve() that + * includes the editor with the specified files. */ static char * -find_editor() +find_editor(argc_out, argv_out) + int *argc_out; + char ***argv_out; { - char *cp, *editor = NULL, **ev, *ev0[4]; + char *cp, *editor, *editor_path = NULL, **ev, *ev0[4]; + /* + * If any of SUDO_EDITOR, VISUAL or EDITOR are set, choose the first one. + */ ev0[0] = "SUDO_EDITOR"; ev0[1] = "VISUAL"; ev0[2] = "EDITOR"; ev0[3] = NULL; for (ev = ev0; *ev != NULL; ev++) { if ((editor = getenv(*ev)) != NULL && *editor != '\0') { - if ((cp = strrchr(editor, '/')) != NULL) - cp++; - else - cp = editor; - /* Ignore "sudoedit" and "sudo" to avoid an endless loop. */ - if (strncmp(cp, "sudo", 4) != 0 || - (cp[4] != ' ' && cp[4] != '\0' && strcmp(cp + 4, "edit") != 0)) { - editor = estrdup(editor); + editor_path = resolve_editor(editor, argc_out, argv_out); + if (editor_path != NULL) break; - } } - editor = NULL; } - if (editor == NULL) { + if (editor_path == NULL) { + /* def_editor could be a path, split it up */ editor = estrdup(def_editor); - if ((cp = strchr(editor, ':')) != NULL) - *cp = '\0'; /* def_editor could be a path */ + cp = strtok(editor, ":"); + while (cp != NULL && editor_path == NULL) { + editor_path = resolve_editor(cp, argc_out, argv_out); + cp = strtok(NULL, ":"); + } + if (editor_path) + efree(editor); + } + if (!editor_path) { + audit_failure(NewArgv, "%s: command not found", editor); + warningx("%s: command not found", editor); } - return(editor); + return editor_path; } + +#else /* HAVE_SETRESUID || HAVE_SETREUID || HAVE_SETEUID */ + +/* + * Must have the ability to change the effective uid to use sudoedit. + */ +int +sudo_edit(argc, argv, envp) + int argc; + char *argv[]; + char *envp[]; +{ + return 1; +} + +#endif /* HAVE_SETRESUID || HAVE_SETREUID || HAVE_SETEUID */