2 * Copyright (c) 1992, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 * Copyright (c) 1992, 1993, 1994, 1995, 1996
5 * Keith Bostic. All rights reserved.
7 * See the LICENSE file for redistribution information.
12 #include <sys/types.h>
13 #include <sys/queue.h>
16 #include <bitstring.h>
24 #include "../common/common.h"
26 #include "pathnames.h"
28 enum rc { NOEXIST, NOPERM, RCOK };
29 static enum rc exrc_isok(SCR *, struct stat *, char *, int, int);
31 static int ex_run_file(SCR *, char *);
37 * PUBLIC: int ex_screen_copy(SCR *, SCR *);
40 ex_screen_copy(SCR *orig, SCR *sp)
42 EX_PRIVATE *oexp, *nexp;
44 /* Create the private ex structure. */
45 CALLOC_RET(orig, nexp, 1, sizeof(EX_PRIVATE));
46 sp->ex_private = nexp;
48 /* Initialize queues. */
50 TAILQ_INIT(nexp->tagfq);
51 SLIST_INIT(nexp->cscq);
57 if (oexp->lastbcomm != NULL &&
58 (nexp->lastbcomm = v_wstrdup(sp, oexp->lastbcomm,
59 STRLEN(oexp->lastbcomm))) == NULL) {
60 msgq(sp, M_SYSERR, NULL);
63 if (ex_tag_copy(orig, sp))
73 * PUBLIC: int ex_screen_end(SCR *);
76 ex_screen_end(SCR *sp)
81 if ((exp = EXP(sp)) == NULL)
86 /* Close down script connections. */
87 if (F_ISSET(sp, SC_SCRIPT) && sscr_end(sp))
97 free(exp->ibcw.bp1.c);
105 /* Free private memory. */
107 sp->ex_private = NULL;
114 * Handle change of options for ex.
116 * PUBLIC: int ex_optchange(SCR *, int, char *, u_long *);
119 ex_optchange(SCR *sp, int offset, char *str, u_long *valp)
123 return (ex_tagf_alloc(sp, str));
130 * Read the EXINIT environment variable and the startup exrc files,
131 * and execute their commands.
133 * PUBLIC: int ex_exrc(SCR *);
138 struct stat hsb, lsb;
144 * Source the system, environment, $HOME and local .exrc values.
145 * Vi historically didn't check $HOME/.exrc if the environment
146 * variable EXINIT was set. This is all done before the file is
147 * read in, because things in the .exrc information can set, for
148 * example, the recovery directory.
151 * While nvi can handle any of the options settings of historic vi,
152 * the converse is not true. Since users are going to have to have
153 * files and environmental variables that work with both, we use nvi
154 * versions of both the $HOME and local startup files if they exist,
155 * otherwise the historic ones.
158 * For a discussion of permissions and when what .exrc files are
159 * read, see the comment above the exrc_isok() function below.
162 * If the user started the historic of vi in $HOME, vi read the user's
163 * .exrc file twice, as $HOME/.exrc and as ./.exrc. We avoid this, as
164 * it's going to make some commands behave oddly, and I can't imagine
165 * anyone depending on it.
167 switch (exrc_isok(sp, &hsb, _PATH_SYSEXRC, 1, 0)) {
172 if (ex_run_file(sp, _PATH_SYSEXRC))
177 /* Run the commands. */
178 if (EXCMD_RUNNING(sp->gp))
180 if (F_ISSET(sp, SC_EXIT | SC_EXIT_FORCE))
183 if ((p = getenv("NEXINIT")) != NULL) {
184 CHAR2INT(sp, p, strlen(p) + 1, wp, wlen);
185 if (ex_run_str(sp, "NEXINIT", wp, wlen - 1, 1, 0))
187 } else if ((p = getenv("EXINIT")) != NULL) {
188 CHAR2INT(sp, p, strlen(p) + 1, wp, wlen);
189 if (ex_run_str(sp, "EXINIT", wp, wlen - 1, 1, 0))
191 } else if ((p = getenv("HOME")) != NULL && *p) {
194 if ((path = join(p, _PATH_NEXRC)) == NULL) {
195 msgq(sp, M_SYSERR, NULL);
198 switch (exrc_isok(sp, &hsb, path, 0, 1)) {
201 if ((path = join(p, _PATH_EXRC)) == NULL) {
202 msgq(sp, M_SYSERR, NULL);
206 &hsb, path, 0, 1) == RCOK && ex_run_file(sp, path))
212 if (ex_run_file(sp, path))
221 /* Run the commands. */
222 if (EXCMD_RUNNING(sp->gp))
224 if (F_ISSET(sp, SC_EXIT | SC_EXIT_FORCE))
227 /* Previous commands may have set the exrc option. */
228 if (O_ISSET(sp, O_EXRC)) {
229 switch (exrc_isok(sp, &lsb, _PATH_NEXRC, 0, 0)) {
231 if (exrc_isok(sp, &lsb, _PATH_EXRC, 0, 0) == RCOK &&
232 (lsb.st_dev != hsb.st_dev ||
233 lsb.st_ino != hsb.st_ino) &&
234 ex_run_file(sp, _PATH_EXRC))
240 if ((lsb.st_dev != hsb.st_dev ||
241 lsb.st_ino != hsb.st_ino) &&
242 ex_run_file(sp, _PATH_NEXRC))
246 /* Run the commands. */
247 if (EXCMD_RUNNING(sp->gp))
249 if (F_ISSET(sp, SC_EXIT | SC_EXIT_FORCE))
258 * Set up a file of ex commands to run.
261 ex_run_file(SCR *sp, char *name)
267 ex_cinit(sp, &cmd, C_SOURCE, 0, OOBLNO, OOBLNO, 0);
268 CHAR2INT(sp, name, strlen(name)+1, wp, wlen);
269 argv_exp0(sp, &cmd, wp, wlen - 1);
270 return (ex_source(sp, &cmd));
275 * Set up a string of ex commands to run.
277 * PUBLIC: int ex_run_str(SCR *, char *, CHAR_T *, size_t, int, int);
280 ex_run_str(SCR *sp, char *name, CHAR_T *str, size_t len, int ex_flags, int nocopy)
286 if (EXCMD_RUNNING(gp)) {
287 CALLOC_RET(sp, ecp, 1, sizeof(EXCMD));
288 SLIST_INSERT_HEAD(gp->ecq, ecp, q);
293 ex_flags ? E_BLIGNORE | E_NOAUTO | E_NOPRDEF | E_VLITONLY : 0);
298 if ((ecp->cp = v_wstrdup(sp, str, len)) == NULL)
305 if ((ecp->if_name = v_strdup(sp, name, strlen(name))) == NULL)
308 F_SET(ecp, E_NAMEDISCARD);
316 * Check a .exrc file for source-ability.
319 * Historically, vi read the $HOME and local .exrc files if they were owned
320 * by the user's real ID, or the "sourceany" option was set, regardless of
321 * any other considerations. We no longer support the sourceany option as
322 * it's a security problem of mammoth proportions. We require the system
323 * .exrc file to be owned by root, the $HOME .exrc file to be owned by the
324 * user's effective ID (or that the user's effective ID be root) and the
325 * local .exrc files to be owned by the user's effective ID. In all cases,
326 * the file cannot be writeable by anyone other than its owner.
328 * In O'Reilly ("Learning the VI Editor", Fifth Ed., May 1992, page 106),
329 * it notes that System V release 3.2 and later has an option "[no]exrc".
330 * The behavior is that local .exrc files are read only if the exrc option
331 * is set. The default for the exrc option was off, so, by default, local
332 * .exrc files were not read. The problem this was intended to solve was
333 * that System V permitted users to give away files, so there's no possible
334 * ownership or writeability test to ensure that the file is safe.
336 * POSIX 1003.2-1992 standardized exrc as an option. It required the exrc
337 * option to be off by default, thus local .exrc files are not to be read
338 * by default. The Rationale noted (incorrectly) that this was a change
339 * to historic practice, but correctly noted that a default of off improves
340 * system security. POSIX also required that vi check the effective user
341 * ID instead of the real user ID, which is why we've switched from historic
344 * We initialize the exrc variable to off. If it's turned on by the system
345 * or $HOME .exrc files, and the local .exrc file passes the ownership and
346 * writeability tests, then we read it. This breaks historic 4BSD practice,
347 * but it gives us a measure of security on systems where users can give away
351 exrc_isok(SCR *sp, struct stat *sbp, char *path, int rootown, int rootid)
353 enum { ROOTOWN, OWN, WRITER } etype;
358 /* Check for the file's existence. */
362 /* Check ownership permissions. */
364 if (!(rootown && sbp->st_uid == 0) &&
365 !(rootid && euid == 0) && sbp->st_uid != euid) {
366 etype = rootown ? ROOTOWN : OWN;
370 /* Check writeability. */
371 if (sbp->st_mode & (S_IWGRP | S_IWOTH)) {
377 denied: a = msg_print(sp, path, &nf1);
378 if (strchr(path, '/') == NULL && (buf = getcwd(NULL, 0)) != NULL) {
381 b = msg_print(sp, buf, &nf2);
382 if ((p = join(b, a)) == NULL) {
383 msgq(sp, M_SYSERR, NULL);
389 "128|%s: not sourced: not owned by you or root", p);
393 "129|%s: not sourced: not owned by you", p);
397 "130|%s: not sourced: writeable by a user other than the owner", p);
403 FREE_SPACE(sp, b, 0);
408 "128|%s: not sourced: not owned by you or root", a);
412 "129|%s: not sourced: not owned by you", a);
416 "130|%s: not sourced: writeable by a user other than the owner", a);
421 FREE_SPACE(sp, a, 0);