1 /* taint.c
2 *
3 * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, by Larry Wall and others
5 *
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
8 *
9 */
10
11 /*
12 * "...we will have peace, when you and all your works have perished--and
13 * the works of your dark master to whom you would deliver us. You are a
14 * liar, Saruman, and a corrupter of men's hearts." --Theoden
15 */
16
17 #include "EXTERN.h"
18 #define PERL_IN_TAINT_C
19 #include "perl.h"
20
21 void
Perl_taint_proper(pTHX_ const char * f,const char * s)22 Perl_taint_proper(pTHX_ const char *f, const char *s)
23 {
24 char *ug;
25
26 #if defined(HAS_SETEUID) && defined(DEBUGGING)
27 # if Uid_t_size == 1
28 {
29 UV uid = PL_uid;
30 UV euid = PL_euid;
31
32 DEBUG_u(PerlIO_printf(Perl_debug_log,
33 "%s %d %"UVuf" %"UVuf"\n",
34 s, PL_tainted, uid, euid));
35 }
36 # else
37 {
38 IV uid = PL_uid;
39 IV euid = PL_euid;
40
41 DEBUG_u(PerlIO_printf(Perl_debug_log,
42 "%s %d %"IVdf" %"IVdf"\n",
43 s, PL_tainted, uid, euid));
44 }
45 # endif
46 #endif
47
48 if (PL_tainted) {
49 if (!f)
50 f = PL_no_security;
51 if (PL_euid != PL_uid)
52 ug = " while running setuid";
53 else if (PL_egid != PL_gid)
54 ug = " while running setgid";
55 else if (PL_taint_warn)
56 ug = " while running with -t switch";
57 else
58 ug = " while running with -T switch";
59 if (PL_unsafe || PL_taint_warn) {
60 if(ckWARN(WARN_TAINT))
61 Perl_warner(aTHX_ packWARN(WARN_TAINT), f, s, ug);
62 }
63 else {
64 Perl_croak(aTHX_ f, s, ug);
65 }
66 }
67 }
68
69 void
Perl_taint_env(pTHX)70 Perl_taint_env(pTHX)
71 {
72 SV** svp;
73 MAGIC* mg;
74 char** e;
75 static char* misc_env[] = {
76 "IFS", /* most shells' inter-field separators */
77 "CDPATH", /* ksh dain bramage #1 */
78 "ENV", /* ksh dain bramage #2 */
79 "BASH_ENV", /* bash dain bramage -- I guess it's contagious */
80 NULL
81 };
82
83 if (!PL_envgv)
84 return;
85
86 #ifdef VMS
87 {
88 int i = 0;
89 char name[10 + TYPE_DIGITS(int)] = "DCL$PATH";
90
91 while (1) {
92 if (i)
93 (void)sprintf(name,"DCL$PATH;%d", i);
94 svp = hv_fetch(GvHVn(PL_envgv), name, strlen(name), FALSE);
95 if (!svp || *svp == &PL_sv_undef)
96 break;
97 if (SvTAINTED(*svp)) {
98 TAINT;
99 taint_proper("Insecure %s%s", "$ENV{DCL$PATH}");
100 }
101 if ((mg = mg_find(*svp, PERL_MAGIC_envelem)) && MgTAINTEDDIR(mg)) {
102 TAINT;
103 taint_proper("Insecure directory in %s%s", "$ENV{DCL$PATH}");
104 }
105 i++;
106 }
107 }
108 #endif /* VMS */
109
110 svp = hv_fetch(GvHVn(PL_envgv),"PATH",4,FALSE);
111 if (svp && *svp) {
112 if (SvTAINTED(*svp)) {
113 TAINT;
114 taint_proper("Insecure %s%s", "$ENV{PATH}");
115 }
116 if ((mg = mg_find(*svp, PERL_MAGIC_envelem)) && MgTAINTEDDIR(mg)) {
117 TAINT;
118 taint_proper("Insecure directory in %s%s", "$ENV{PATH}");
119 }
120 }
121
122 #ifndef VMS
123 /* tainted $TERM is okay if it contains no metachars */
124 svp = hv_fetch(GvHVn(PL_envgv),"TERM",4,FALSE);
125 if (svp && *svp && SvTAINTED(*svp)) {
126 STRLEN n_a;
127 bool was_tainted = PL_tainted;
128 char *t = SvPV(*svp, n_a);
129 char *e = t + n_a;
130 PL_tainted = was_tainted;
131 if (t < e && isALNUM(*t))
132 t++;
133 while (t < e && (isALNUM(*t) || strchr("-_.+", *t)))
134 t++;
135 if (t < e) {
136 TAINT;
137 taint_proper("Insecure $ENV{%s}%s", "TERM");
138 }
139 }
140 #endif /* !VMS */
141
142 for (e = misc_env; *e; e++) {
143 svp = hv_fetch(GvHVn(PL_envgv), *e, strlen(*e), FALSE);
144 if (svp && *svp != &PL_sv_undef && SvTAINTED(*svp)) {
145 TAINT;
146 taint_proper("Insecure $ENV{%s}%s", *e);
147 }
148 }
149 }
150