xref: /onnv-gate/usr/src/cmd/sgs/libconv/common/lddstub.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
27*0Sstevel@tonic-gate 
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate #include	<unistd.h>
30*0Sstevel@tonic-gate #include	<strings.h>
31*0Sstevel@tonic-gate #include	<limits.h>
32*0Sstevel@tonic-gate #include	<dlfcn.h>
33*0Sstevel@tonic-gate #include	"_conv.h"
34*0Sstevel@tonic-gate #include	"lddstub_msg.h"
35*0Sstevel@tonic-gate 
36*0Sstevel@tonic-gate static char	orgstub[PATH_MAX];
37*0Sstevel@tonic-gate static char	orgstub64[PATH_MAX];
38*0Sstevel@tonic-gate static int	orgflag;
39*0Sstevel@tonic-gate static int	orgflag64;
40*0Sstevel@tonic-gate 
41*0Sstevel@tonic-gate #ifdef NEED_OWN_STRLCAT
42*0Sstevel@tonic-gate /*
43*0Sstevel@tonic-gate  * Appends src to the dstsize buffer at dst. The append will never
44*0Sstevel@tonic-gate  * overflow the destination buffer and the buffer will always be null
45*0Sstevel@tonic-gate  * terminated. Never reference beyond &bst[dstsize-1] when computing
46*0Sstevel@tonic-gate  * the length of the pre-existing string.
47*0Sstevel@tonic-gate  */
48*0Sstevel@tonic-gate size_t
49*0Sstevel@tonic-gate strlcat(char *dst, const char *src, size_t dstsize)
50*0Sstevel@tonic-gate {
51*0Sstevel@tonic-gate 	char *df = dst;
52*0Sstevel@tonic-gate 	size_t left = dstsize;
53*0Sstevel@tonic-gate 	size_t l1;
54*0Sstevel@tonic-gate 	size_t l2 = strlen(src);
55*0Sstevel@tonic-gate 	size_t copied;
56*0Sstevel@tonic-gate 
57*0Sstevel@tonic-gate 	while (left-- != 0 && *df != '\0')
58*0Sstevel@tonic-gate 		df++;
59*0Sstevel@tonic-gate 	l1 = df - dst;
60*0Sstevel@tonic-gate 	if (dstsize == l1)
61*0Sstevel@tonic-gate 		return (l1 + l2);
62*0Sstevel@tonic-gate 
63*0Sstevel@tonic-gate 	copied = l1 + l2 >= dstsize ? dstsize - l1 - 1 : l2;
64*0Sstevel@tonic-gate 	memcpy(dst + l1, src, copied);
65*0Sstevel@tonic-gate 	dst[l1+copied] = '\0';
66*0Sstevel@tonic-gate 	return (l1 + l2);
67*0Sstevel@tonic-gate }
68*0Sstevel@tonic-gate #endif
69*0Sstevel@tonic-gate 
70*0Sstevel@tonic-gate static int
71*0Sstevel@tonic-gate originlddstub(char *buffer, const char *orgfile)
72*0Sstevel@tonic-gate {
73*0Sstevel@tonic-gate 	int	len;
74*0Sstevel@tonic-gate 
75*0Sstevel@tonic-gate 	if (dlinfo(RTLD_SELF, RTLD_DI_ORIGIN, (void *)buffer) == -1)
76*0Sstevel@tonic-gate 		return (-1);
77*0Sstevel@tonic-gate 	if (strlcat(buffer, orgfile, PATH_MAX) >= PATH_MAX)
78*0Sstevel@tonic-gate 		return (-1);
79*0Sstevel@tonic-gate 	if ((len = resolvepath(buffer, buffer, (PATH_MAX - 1))) == -1)
80*0Sstevel@tonic-gate 		return (-1);
81*0Sstevel@tonic-gate 	buffer[len] = '\0';
82*0Sstevel@tonic-gate 	if (access(orgstub, X_OK) == -1)
83*0Sstevel@tonic-gate 		return (-1);
84*0Sstevel@tonic-gate 
85*0Sstevel@tonic-gate 	return (0);
86*0Sstevel@tonic-gate }
87*0Sstevel@tonic-gate 
88*0Sstevel@tonic-gate /*
89*0Sstevel@tonic-gate  * Determine what lddstub to run.
90*0Sstevel@tonic-gate  */
91*0Sstevel@tonic-gate const char *
92*0Sstevel@tonic-gate conv_lddstub(int class)
93*0Sstevel@tonic-gate {
94*0Sstevel@tonic-gate 	const char *stub;
95*0Sstevel@tonic-gate 
96*0Sstevel@tonic-gate 	/*
97*0Sstevel@tonic-gate 	 * Establish defaults.
98*0Sstevel@tonic-gate 	 */
99*0Sstevel@tonic-gate 	if (class == ELFCLASS32)
100*0Sstevel@tonic-gate 		stub = MSG_ORIG(MSG_PTH_LDDSTUB);
101*0Sstevel@tonic-gate 	else
102*0Sstevel@tonic-gate 		stub = MSG_ORIG(MSG_PTH_LDDSTUB_64);
103*0Sstevel@tonic-gate 
104*0Sstevel@tonic-gate 	/*
105*0Sstevel@tonic-gate 	 * Provided we're not secure, determine lddstub's location from our
106*0Sstevel@tonic-gate 	 * own origin.
107*0Sstevel@tonic-gate 	 */
108*0Sstevel@tonic-gate 	if (geteuid()) {
109*0Sstevel@tonic-gate 		if ((class == ELFCLASS32) && (orgflag != -1)) {
110*0Sstevel@tonic-gate 			if (orgflag == 0) {
111*0Sstevel@tonic-gate 				if ((orgflag = originlddstub(orgstub,
112*0Sstevel@tonic-gate 				    MSG_ORIG(MSG_ORG_LDDSTUB))) == -1)
113*0Sstevel@tonic-gate 					return (stub);
114*0Sstevel@tonic-gate 			}
115*0Sstevel@tonic-gate 			stub = (const char *)orgstub;
116*0Sstevel@tonic-gate 		}
117*0Sstevel@tonic-gate 		if ((class == ELFCLASS64) && (orgflag64 != -1)) {
118*0Sstevel@tonic-gate 			if (orgflag64 == 0) {
119*0Sstevel@tonic-gate 				if ((orgflag64 = originlddstub(orgstub64,
120*0Sstevel@tonic-gate 				    MSG_ORIG(MSG_ORG_LDDSTUB_64))) == -1)
121*0Sstevel@tonic-gate 					return (stub);
122*0Sstevel@tonic-gate 			}
123*0Sstevel@tonic-gate 			stub = (const char *)orgstub64;
124*0Sstevel@tonic-gate 		}
125*0Sstevel@tonic-gate 	}
126*0Sstevel@tonic-gate 	return (stub);
127*0Sstevel@tonic-gate }
128