1 | /* |
2 | * This file is part of the KDE libraries |
3 | * Copyright (c) 2007 Lubos Lunak <l.lunak@kde.org> |
4 | * |
5 | * This library is free software; you can redistribute it and/or |
6 | * modify it under the terms of the GNU Library General Public |
7 | * License version 2 as published by the Free Software Foundation. |
8 | * |
9 | * This library is distributed in the hope that it will be useful, |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | * Library General Public License for more details. |
13 | * |
14 | * You should have received a copy of the GNU Library General Public License |
15 | * along with this library; see the file COPYING.LIB. If not, write to |
16 | * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
17 | * Boston, MA 02110-1301, USA. |
18 | */ |
19 | |
20 | #include <config.h> |
21 | #include <config-prefix.h> |
22 | #include <config-kdeinit.h> |
23 | |
24 | #include <stdio.h> |
25 | #include <string.h> |
26 | #include <unistd.h> |
27 | |
28 | #define EXECUTE LIBEXEC_INSTALL_DIR "/start_kdeinit" |
29 | |
30 | #ifdef KDEINIT_OOM_PROTECT |
31 | |
32 | /* |
33 | The start_kdeinit wrapper is setuid, which means some shell variables like LD_LIBRARY_PATH |
34 | get unset before it's launched. However kdeinit is used to launch most of KDE, so such variables |
35 | should not be dropped. Therefore this wrapper for the setuid wrapper read the environment |
36 | and writes it to start_kdeinit's stdin, which after dropping privileges reads it and uses it |
37 | for launching the real kdeinit. |
38 | */ |
39 | int main(int argc, char **argv) |
40 | { |
41 | int pipes[ 2 ]; |
42 | if(argc == 0) |
43 | return 1; |
44 | if( pipe( pipes ) < 0 ) { |
45 | perror( "pipe()" ); |
46 | return 1; |
47 | } |
48 | switch( fork()) { |
49 | case -1: |
50 | perror( "fork()" ); |
51 | return 1; |
52 | default: /* parent, exec */ |
53 | close( pipes[ 1 ] ); |
54 | close( 0 ); /* stdin */ |
55 | dup2( pipes[ 0 ], 0 ); |
56 | close( pipes[ 0 ] ); |
57 | argv[ 0 ] = (char*)EXECUTE; |
58 | execvp(EXECUTE, argv); |
59 | perror("start_kdeinit" ); |
60 | return 1; |
61 | case 0: { /* child, pass env and exit */ |
62 | extern char** environ; |
63 | int i; |
64 | close( pipes[ 0 ] ); |
65 | write( pipes[ 1 ], "environ" , 7 ); /* header, just in case */ |
66 | for( i = 0; |
67 | environ[ i ] != NULL; |
68 | ++i ) |
69 | {} |
70 | write( pipes[ 1 ], &i, sizeof( int )); /* write count */ |
71 | for( i = 0; |
72 | environ[ i ] != NULL; |
73 | ++i ) |
74 | { |
75 | int len = strlen( environ[ i ] ); |
76 | write( pipes[ 1 ], &len, sizeof( int )); /* write length */ |
77 | write( pipes[ 1 ], environ[ i ], strlen( environ[ i ] )); |
78 | } |
79 | close( pipes[ 1 ] ); |
80 | } |
81 | } |
82 | return 0; |
83 | } |
84 | |
85 | #else /* not Linux, the simple non-setuid case */ |
86 | |
87 | int main(int argc, char **argv) |
88 | { |
89 | if(argc == 0) |
90 | return 1; |
91 | argv[0] = (char*)EXECUTE; |
92 | execvp(EXECUTE,argv); |
93 | perror("start_kdeinit" ); |
94 | return 1; |
95 | } |
96 | #endif |
97 | |