On 2024-12-08 23:45, Paul Eggert wrote:
On 2024-12-08 14:06, Brian Inglis via tz wrote:
Disallowing these would also likely disallow variations on:
$ zdump /usr/share/zoneinfo/.../...
$ zdump <(...)
...
Although it disallows the second variation, that's also true for zdump
when built with glibc.... Perhaps we can change zdump
to allow that sort of thing, but this will need further thought.
I did that for zdump when built with tzcode by installing the attached
proposed patch.From 6d77c92872c0dc5ee0d6189d77337882596768a3 Mon Sep 17 00:00:00 2001
From: Paul Eggert <[email protected]>
Date: Mon, 9 Dec 2024 12:55:10 -0800
Subject: [PATCH] Bring back zdump on a pipe
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Problem reported by Brian Inglis in:
https://lists.iana.org/hyperkitty/list/[email protected]/message/5SIPUZ7BXJIGMU7LK3T4SRWDXQ2XUYVP/
* localtime.c (TZLOAD_FROMENV, TZLOAD_TZSTRING): New constants.
(tzloadbody, tzload): Accept tzloadflags instead of merely doextend.
All callers changed.
(tzloadbody): Do access-related checks only for TZ settings taken
from the environment. Don’t do them for tzalloc, since callers
like zdump should know what they’re doing and need the extra
generality.
(zoneinit): Accept tzloadflags. All callers changed.
---
localtime.c | 39 ++++++++++++++++++++++-----------------
1 file changed, 22 insertions(+), 17 deletions(-)
diff --git a/localtime.c b/localtime.c
index fb0ea731..566d2347 100644
--- a/localtime.c
+++ b/localtime.c
@@ -500,11 +500,15 @@ union local_storage {
char fullname[max(sizeof(struct file_analysis), sizeof tzdirslash + 1024)];
};
-/* Load tz data from the file named NAME into *SP. Read extended
- format if DOEXTEND. Use *LSP for temporary storage. Return 0 on
+/* These tzload flags can be ORed together, and fit into 'char'. */
+enum { TZLOAD_FROMENV = 1 }; /* The TZ string came from the environment. */
+enum { TZLOAD_TZSTRING = 2 }; /* Read any newline-surrounded TZ string. */
+
+/* Load tz data from the file named NAME into *SP. Respect TZLOADFLAGS.
+ Use *LSP for temporary storage. Return 0 on
success, an errno value on failure. */
static int
-tzloadbody(char const *name, struct state *sp, bool doextend,
+tzloadbody(char const *name, struct state *sp, char tzloadflags,
union local_storage *lsp)
{
register int i;
@@ -555,7 +559,7 @@ tzloadbody(char const *name, struct state *sp, bool doextend,
name = lsp->fullname;
}
- if (doaccess) {
+ if (doaccess && (tzloadflags & TZLOAD_FROMENV)) {
/* Check for security violations and for devices whose mere
opening could have unwanted side effects. Although these
checks are racy, they're better than nothing and there is
@@ -751,7 +755,7 @@ tzloadbody(char const *name, struct state *sp, bool doextend,
if (!version)
break;
}
- if (doextend && nread > 2 &&
+ if ((tzloadflags & TZLOAD_TZSTRING) && nread > 2 &&
up->buf[0] == '\n' && up->buf[nread - 1] == '\n' &&
sp->typecnt + 2 <= TZ_MAX_TYPES) {
struct state *ts = &lsp->u.st;
@@ -826,23 +830,23 @@ tzloadbody(char const *name, struct state *sp, bool doextend,
return 0;
}
-/* Load tz data from the file named NAME into *SP. Read extended
- format if DOEXTEND. Return 0 on success, an errno value on failure. */
+/* Load tz data from the file named NAME into *SP. Respect TZLOADFLAGS.
+ Return 0 on success, an errno value on failure. */
static int
-tzload(char const *name, struct state *sp, bool doextend)
+tzload(char const *name, struct state *sp, char tzloadflags)
{
#ifdef ALL_STATE
union local_storage *lsp = malloc(sizeof *lsp);
if (!lsp) {
return HAVE_MALLOC_ERRNO ? errno : ENOMEM;
} else {
- int err = tzloadbody(name, sp, doextend, lsp);
+ int err = tzloadbody(name, sp, tzloadflags, lsp);
free(lsp);
return err;
}
#else
union local_storage ls;
- return tzloadbody(name, sp, doextend, &ls);
+ return tzloadbody(name, sp, tzloadflags, &ls);
#endif
}
@@ -1183,7 +1187,7 @@ tzparse(const char *name, struct state *sp, struct state const *basep)
sp->leapcnt = basep->leapcnt;
memcpy(sp->lsis, basep->lsis, sp->leapcnt * sizeof *sp->lsis);
} else {
- load_ok = tzload(TZDEFRULES, sp, false) == 0;
+ load_ok = tzload(TZDEFRULES, sp, 0) == 0;
if (!load_ok)
sp->leapcnt = 0; /* So, we're off a little. */
}
@@ -1420,16 +1424,17 @@ tzparse(const char *name, struct state *sp, struct state const *basep)
static void
gmtload(struct state *const sp)
{
- if (tzload(etc_utc, sp, true) != 0)
+ if (tzload(etc_utc, sp, TZLOAD_TZSTRING) != 0)
tzparse("UTC0", sp, NULL);
}
#if !USE_TIMEX_T || !defined TM_GMTOFF
/* Initialize *SP to a value appropriate for the TZ setting NAME.
+ Respect TZLOADFLAGS.
Return 0 on success, an errno value on failure. */
static int
-zoneinit(struct state *sp, char const *name)
+zoneinit(struct state *sp, char const *name, char tzloadflags)
{
if (name && ! name[0]) {
/*
@@ -1444,7 +1449,7 @@ zoneinit(struct state *sp, char const *name)
strcpy(sp->chars, utc);
return 0;
} else {
- int err = tzload(name, sp, true);
+ int err = tzload(name, sp, tzloadflags);
if (err != 0 && name && name[0] != ':' && tzparse(name, sp, NULL))
err = 0;
if (err == 0)
@@ -1468,8 +1473,8 @@ tzset_unlocked(void)
lclptr = sp = malloc(sizeof *lclptr);
# endif
if (sp) {
- if (zoneinit(sp, name) != 0) {
- zoneinit(sp, "");
+ if (zoneinit(sp, name, TZLOAD_FROMENV | TZLOAD_TZSTRING) != 0) {
+ zoneinit(sp, "", 0);
strcpy(sp->chars, UNSPEC);
}
if (0 < lcl)
@@ -1516,7 +1521,7 @@ tzalloc(char const *name)
{
timezone_t sp = malloc(sizeof *sp);
if (sp) {
- int err = zoneinit(sp, name);
+ int err = zoneinit(sp, name, TZLOAD_TZSTRING);
if (err != 0) {
free(sp);
errno = err;
--
2.47.1
