1 files changed, 113 insertions, 0 deletions
diff --git a/contrib/perl5/taint.c b/contrib/perl5/taint.c
new file mode 100644
index 0000000..4c031de
--- /dev/null
+++ b/contrib/perl5/taint.c
@@ -0,0 +1,113 @@
+/*
+ * "...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
+ */
+
+#include "EXTERN.h"
+#include "perl.h"
+
+void
+taint_proper(const char *f, char *s)
+{
+    dTHR;	/* just for taint */
+    char *ug;
+
+    DEBUG_u(PerlIO_printf(Perl_debug_log,
+            "%s %d %d %d\n", s, PL_tainted, PL_uid, PL_euid));
+
+    if (PL_tainted) {
+	if (PL_euid != PL_uid)
+	    ug = " while running setuid";
+	else if (PL_egid != PL_gid)
+	    ug = " while running setgid";
+	else
+	    ug = " while running with -T switch";
+	if (!PL_unsafe)
+	    croak(f, s, ug);
+	else if (PL_dowarn)
+	    warn(f, s, ug);
+    }
+}
+
+void
+taint_env(void)
+{
+    SV** svp;
+    MAGIC* mg;
+    char** e;
+    static char* 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 */
+	NULL
+    };
+
+#ifdef VMS
+    int i = 0;
+    char name[10 + TYPE_DIGITS(int)] = "DCL$PATH";
+
+    while (1) {
+	if (i)
+	    (void)sprintf(name,"DCL$PATH;%d", i);
+	svp = hv_fetch(GvHVn(PL_envgv), name, strlen(name), FALSE);
+	if (!svp || *svp == &PL_sv_undef)
+	    break;
+	if (SvTAINTED(*svp)) {
+	    dTHR;
+	    TAINT;
+	    taint_proper("Insecure %s%s", "$ENV{DCL$PATH}");
+	}
+	if ((mg = mg_find(*svp, 'e')) && MgTAINTEDDIR(mg)) {
+	    dTHR;
+	    TAINT;
+	    taint_proper("Insecure directory in %s%s", "$ENV{DCL$PATH}");
+	}
+	i++;
+    }
+#endif /* VMS */
+
+    svp = hv_fetch(GvHVn(PL_envgv),"PATH",4,FALSE);
+    if (svp && *svp) {
+	if (SvTAINTED(*svp)) {
+	    dTHR;
+	    TAINT;
+	    taint_proper("Insecure %s%s", "$ENV{PATH}");
+	}
+	if ((mg = mg_find(*svp, 'e')) && MgTAINTEDDIR(mg)) {
+	    dTHR;
+	    TAINT;
+	    taint_proper("Insecure directory in %s%s", "$ENV{PATH}");
+	}
+    }
+
+#ifndef VMS
+    /* tainted $TERM is okay if it contains no metachars */
+    svp = hv_fetch(GvHVn(PL_envgv),"TERM",4,FALSE);
+    if (svp && *svp && SvTAINTED(*svp)) {
+    	dTHR;	/* just for taint */
+	bool was_tainted = PL_tainted;
+	char *t = SvPV(*svp, PL_na);
+	char *e = t + PL_na;
+	PL_tainted = was_tainted;
+	if (t < e && isALNUM(*t))
+	    t++;
+	while (t < e && (isALNUM(*t) || *t == '-' || *t == ':'))
+	    t++;
+	if (t < e) {
+	    TAINT;
+	    taint_proper("Insecure $ENV{%s}%s", "TERM");
+	}
+    }
+#endif /* !VMS */
+
+    for (e = misc_env; *e; e++) {
+	svp = hv_fetch(GvHVn(PL_envgv), *e, strlen(*e), FALSE);
+	if (svp && *svp != &PL_sv_undef && SvTAINTED(*svp)) {
+	    dTHR;	/* just for taint */
+	    TAINT;
+	    taint_proper("Insecure $ENV{%s}%s", *e);
+	}
+    }
+}