3 * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
4 * 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
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.
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.' --Théoden
16 * [p.580 of _The Lord of the Rings_, III/x: "The Voice of Saruman"]
19 /* This file contains a few functions for handling data tainting in Perl
23 #define PERL_IN_TAINT_C
27 =for apidoc taint_proper
29 Implements the L</TAINT_PROPER> macro, which you should generally use instead.
35 Perl_taint_proper(pTHX_ const char *f, const char *const s)
37 /* Output a tainting violation, croaking unless we're just to warn.
38 * '_proper' is just to throw you off the scent */
40 #if defined(HAS_SETEUID) && defined(DEBUGGING)
41 PERL_ARGS_ASSERT_TAINT_PROPER;
44 const Uid_t uid = PerlProc_getuid();
45 const Uid_t euid = PerlProc_geteuid();
47 #if Uid_t_sign == 1 /* uid_t is unsigned. */
48 DEBUG_u(PerlIO_printf(Perl_debug_log,
49 "%s %d %" UVuf " %" UVuf "\n",
50 s, TAINT_get, (UV)uid, (UV)euid));
51 #else /* uid_t is signed (Uid_t_sign == -1), or don't know. */
52 DEBUG_u(PerlIO_printf(Perl_debug_log,
53 "%s %d %" IVdf " %" IVdf "\n",
54 s, TAINT_get, (IV)uid, (IV)euid));
64 if (PerlProc_getuid() != PerlProc_geteuid())
65 ug = " while running setuid";
66 else if (PerlProc_getgid() != PerlProc_getegid())
67 ug = " while running setgid";
68 else if (TAINT_WARN_get)
69 ug = " while running with -t switch";
71 ug = " while running with -T switch";
73 /* XXX because taint_proper adds extra format args, we can't
74 * get the caller to check properly; so we just silence the warning
75 * and hope the callers aren't naughty */
76 GCC_DIAG_IGNORE_STMT(-Wformat-nonliteral);
77 if (PL_unsafe || TAINT_WARN_get) {
78 Perl_ck_warner_d(aTHX_ packWARN(WARN_TAINT), f, s, ug);
81 Perl_croak(aTHX_ f, s, ug);
83 GCC_DIAG_RESTORE_STMT;
91 Implements the L</TAINT_ENV> macro, which you should generally use instead.
100 static const char* const misc_env[] = {
101 "IFS", /* most shells' inter-field separators */
102 "CDPATH", /* ksh dain bramage #1 */
103 "ENV", /* ksh dain bramage #2 */
104 "BASH_ENV", /* bash dain bramage -- I guess it's contagious */
106 "PERL5SHELL", /* used for system() on Windows */
111 /* Don't bother if there's no *ENV glob */
114 /* If there's no %ENV hash or if it's not magical, croak, because
115 * it probably doesn't reflect the actual environment */
116 if (!GvHV(PL_envgv) || !(SvRMAGICAL(GvHV(PL_envgv))
117 && mg_find((const SV *)GvHV(PL_envgv), PERL_MAGIC_env))) {
118 const bool was_tainted = TAINT_get;
119 const char * const name = GvENAME(PL_envgv);
121 if (strEQ(name,"ENV"))
123 taint_proper("%%ENV is aliased to %s%s", "another variable");
125 /* glob alias: report it in the error message */
126 taint_proper("%%ENV is aliased to %%%s%s", name);
127 /* this statement is reached under -t or -U */
128 TAINT_set(was_tainted);
129 #ifdef NO_TAINT_SUPPORT
130 PERL_UNUSED_VAR(was_tainted);
137 char name[10 + TYPE_DIGITS(int)] = "DCL$PATH";
138 STRLEN len = 8; /* strlen(name) */
143 len = my_snprintf(name, sizeof name, "DCL$PATH;%d", i);
144 svp = hv_fetch(GvHVn(PL_envgv), name, len, FALSE);
145 if (!svp || *svp == &PL_sv_undef)
147 if (SvTAINTED(*svp)) {
149 taint_proper("Insecure %s%s", "$ENV{DCL$PATH}");
151 if ((mg = mg_find(*svp, PERL_MAGIC_envelem)) && MgTAINTEDDIR(mg)) {
153 taint_proper("Insecure directory in %s%s", "$ENV{DCL$PATH}");
160 svp = hv_fetchs(GvHVn(PL_envgv),"PATH",FALSE);
163 if (SvTAINTED(*svp)) {
165 taint_proper("Insecure %s%s", "$ENV{PATH}");
167 if ((mg = mg_find(*svp, PERL_MAGIC_envelem)) && MgTAINTEDDIR(mg)) {
169 taint_proper("Insecure directory in %s%s", "$ENV{PATH}");
174 /* tainted $TERM is okay if it contains no metachars */
175 svp = hv_fetchs(GvHVn(PL_envgv),"TERM",FALSE);
176 if (svp && *svp && SvTAINTED(*svp)) {
178 const bool was_tainted = TAINT_get;
179 const char *t = SvPV_const(*svp, len);
180 const char * const e = t + len;
182 TAINT_set(was_tainted);
183 #ifdef NO_TAINT_SUPPORT
184 PERL_UNUSED_VAR(was_tainted);
186 if (t < e && isWORDCHAR(*t))
188 while (t < e && (isWORDCHAR(*t) || memCHRs("-_.+", *t)))
192 taint_proper("Insecure $ENV{%s}%s", "TERM");
197 for (e = misc_env; *e; e++) {
198 SV * const * const svp = hv_fetch(GvHVn(PL_envgv), *e, strlen(*e), FALSE);
199 if (svp && *svp != &PL_sv_undef && SvTAINTED(*svp)) {
201 taint_proper("Insecure $ENV{%s}%s", *e);
207 * ex: set ts=8 sts=4 sw=4 et: