X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/eb1102fcca2230364ceadea29bd8e87ee51b15fa..3ff7ceb302af0696dab5b544b884cc950eaa6f13:/taint.c

diff --git a/taint.c b/taint.c
index ac7a841..62c171f 100644
--- a/taint.c
+++ b/taint.c
@@ -1,6 +1,7 @@
 /*    taint.c
  *
- *    Copyright (c) 1997-2002, Larry Wall
+ *    Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
+ *    2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
  *
  *    You may distribute under the terms of either the GNU General Public
  *    License or the Artistic License, as specified in the README file.
@@ -8,9 +9,14 @@
  */
 
 /*
- * "...we will have peace, when you and all your works have perished--and
- * the works of your dark master to whom you would deliver us.  You are a
- * liar, Saruman, and a corrupter of men's hearts."  --Theoden
+ * '...we will have peace, when you and all your works have perished--and
+ *  the works of your dark master to whom you would deliver us.  You are a
+ *  liar, Saruman, and a corrupter of men's hearts.'       --Théoden
+ *
+ *     [p.580 of _The Lord of the Rings_, III/x: "The Voice of Saruman"]
+ */
+
+/* This file contains a few functions for handling data tainting in Perl
  */
 
 #include "EXTERN.h"
@@ -18,26 +24,28 @@
 #include "perl.h"
 
 void
-Perl_taint_proper(pTHX_ const char *f, const char *s)
+Perl_taint_proper(pTHX_ const char *f, const char *const s)
 {
-    char *ug;
-
 #if defined(HAS_SETEUID) && defined(DEBUGGING)
+    dVAR;
+
+    PERL_ARGS_ASSERT_TAINT_PROPER;
+
 #   if Uid_t_size == 1
     {
-	 UV  uid = PL_uid;
-	 UV euid = PL_euid;
+	const UV  uid = PL_uid;
+	const UV euid = PL_euid;
 
-	 DEBUG_u(PerlIO_printf(Perl_debug_log,
+	DEBUG_u(PerlIO_printf(Perl_debug_log,
 			       "%s %d %"UVuf" %"UVuf"\n",
 			       s, PL_tainted, uid, euid));
     }
 #   else
     {
-	 IV  uid = PL_uid;
-	 IV euid = PL_euid;
+	const IV  uid = PL_uid;
+	const IV euid = PL_euid;
 
-	 DEBUG_u(PerlIO_printf(Perl_debug_log,
+	DEBUG_u(PerlIO_printf(Perl_debug_log,
 			       "%s %d %"IVdf" %"IVdf"\n",
 			       s, PL_tainted, uid, euid));
     }
@@ -45,6 +53,8 @@ Perl_taint_proper(pTHX_ const char *f, const char *s)
 #endif
 
     if (PL_tainted) {
+	const char *ug;
+
 	if (!f)
 	    f = PL_no_security;
 	if (PL_euid != PL_uid)
@@ -56,8 +66,7 @@ Perl_taint_proper(pTHX_ const char *f, const char *s)
         else
 	    ug = " while running with -T switch";
 	if (PL_unsafe || PL_taint_warn) {
-            if(ckWARN(WARN_TAINT))
-                Perl_warner(aTHX_ WARN_TAINT, f, s, ug);
+	    Perl_ck_warner_d(aTHX_ packWARN(WARN_TAINT), f, s, ug);
         }
         else {
             Perl_croak(aTHX_ f, s, ug);
@@ -68,29 +77,51 @@ Perl_taint_proper(pTHX_ const char *f, const char *s)
 void
 Perl_taint_env(pTHX)
 {
+    dVAR;
     SV** svp;
     MAGIC* mg;
-    char** e;
-    static char* misc_env[] = {
+    const char* const *e;
+    static const char* const misc_env[] = {
 	"IFS",		/* most shells' inter-field separators */
 	"CDPATH",	/* ksh dain bramage #1 */
 	"ENV",		/* ksh dain bramage #2 */
 	"BASH_ENV",	/* bash dain bramage -- I guess it's contagious */
+#ifdef WIN32
+	"PERL5SHELL",	/* used for system() on Windows */
+#endif
 	NULL
     };
 
+    /* Don't bother if there's no *ENV glob */
     if (!PL_envgv)
 	return;
+    /* If there's no %ENV hash of if it's not magical, croak, because
+     * it probably doesn't reflect the actual environment */
+    if (!GvHV(PL_envgv) || !(SvRMAGICAL(GvHV(PL_envgv))
+	    && mg_find((const SV *)GvHV(PL_envgv), PERL_MAGIC_env))) {
+	const bool was_tainted = PL_tainted;
+	const char * const name = GvENAME(PL_envgv);
+	PL_tainted = TRUE;
+	if (strEQ(name,"ENV"))
+	    /* hash alias */
+	    taint_proper("%%ENV is aliased to %s%s", "another variable");
+	else
+	    /* glob alias: report it in the error message */
+	    taint_proper("%%ENV is aliased to %%%s%s", name);
+	/* this statement is reached under -t or -U */
+	PL_tainted = was_tainted;
+    }
 
 #ifdef VMS
     {
     int i = 0;
     char name[10 + TYPE_DIGITS(int)] = "DCL$PATH";
+    STRLEN len = 8; /* strlen(name)  */
 
     while (1) {
 	if (i)
-	    (void)sprintf(name,"DCL$PATH;%d", i);
-	svp = hv_fetch(GvHVn(PL_envgv), name, strlen(name), FALSE);
+	    len = my_sprintf(name,"DCL$PATH;%d", i);
+	svp = hv_fetch(GvHVn(PL_envgv), name, len, FALSE);
 	if (!svp || *svp == &PL_sv_undef)
 	    break;
 	if (SvTAINTED(*svp)) {
@@ -106,7 +137,7 @@ Perl_taint_env(pTHX)
   }
 #endif /* VMS */
 
-    svp = hv_fetch(GvHVn(PL_envgv),"PATH",4,FALSE);
+    svp = hv_fetchs(GvHVn(PL_envgv),"PATH",FALSE);
     if (svp && *svp) {
 	if (SvTAINTED(*svp)) {
 	    TAINT;
@@ -120,16 +151,16 @@ Perl_taint_env(pTHX)
 
 #ifndef VMS
     /* tainted $TERM is okay if it contains no metachars */
-    svp = hv_fetch(GvHVn(PL_envgv),"TERM",4,FALSE);
+    svp = hv_fetchs(GvHVn(PL_envgv),"TERM",FALSE);
     if (svp && *svp && SvTAINTED(*svp)) {
-	STRLEN n_a;
-	bool was_tainted = PL_tainted;
-	char *t = SvPV(*svp, n_a);
-	char *e = t + n_a;
+	STRLEN len;
+	const bool was_tainted = PL_tainted;
+	const char *t = SvPV_const(*svp, len);
+	const char * const e = t + len;
 	PL_tainted = was_tainted;
 	if (t < e && isALNUM(*t))
 	    t++;
-	while (t < e && (isALNUM(*t) || *t == '-' || *t == ':'))
+	while (t < e && (isALNUM(*t) || strchr("-_.+", *t)))
 	    t++;
 	if (t < e) {
 	    TAINT;
@@ -139,10 +170,20 @@ Perl_taint_env(pTHX)
 #endif /* !VMS */
 
     for (e = misc_env; *e; e++) {
-	svp = hv_fetch(GvHVn(PL_envgv), *e, strlen(*e), FALSE);
+	SV * const * const svp = hv_fetch(GvHVn(PL_envgv), *e, strlen(*e), FALSE);
 	if (svp && *svp != &PL_sv_undef && SvTAINTED(*svp)) {
 	    TAINT;
 	    taint_proper("Insecure $ENV{%s}%s", *e);
 	}
     }
 }
+
+/*
+ * Local variables:
+ * c-indentation-style: bsd
+ * c-basic-offset: 4
+ * indent-tabs-mode: t
+ * End:
+ *
+ * ex: set ts=8 sts=4 sw=4 noet:
+ */