aboutsummaryrefslogtreecommitdiff
path: root/IkiWiki/Wrapper.pm
blob: 6687cace221afc7cca17c35d99a85c3557fd9223 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
#!/usr/bin/perl

use warnings;
use strict;
use Cwd q{abs_path};
use Data::Dumper;
use IkiWiki;

package IkiWiki;

sub gen_wrapper () { #{{{
	$config{srcdir}=abs_path($config{srcdir});
	$config{destdir}=abs_path($config{destdir});
	my $this=abs_path($0);
	if (! -x $this) {
		error(sprintf(gettext("%s doesn't seem to be executable"), $this));
	}

	if ($config{setup}) {
		error(gettext("cannot create a wrapper that uses a setup file"));
	}
	my $wrapper=possibly_foolish_untaint($config{wrapper});
	if (! defined $wrapper || ! length $wrapper) {
		error(gettext("wrapper filename not specified"));
	}
	delete $config{wrapper};
	
	my @envsave;
	push @envsave, qw{REMOTE_ADDR QUERY_STRING REQUEST_METHOD REQUEST_URI
	               CONTENT_TYPE CONTENT_LENGTH GATEWAY_INTERFACE
		       HTTP_COOKIE REMOTE_USER} if $config{cgi};
	my $envsave="";
	foreach my $var (@envsave) {
		$envsave.=<<"EOF"
	if ((s=getenv("$var")))
		addenv("$var", s);
EOF
	}
	if ($config{rcs} eq "svn" && $config{notify}) {
		# Support running directly as hooks/post-commit by passing
		# $2 in REV in the environment.
		$envsave.=<<"EOF"
	if (argc == 3)
		addenv("REV", argv[2]);
	else if ((s=getenv("REV")))
		addenv("REV", s);
EOF
	}
	if ($config{rcs} eq "tla" && $config{notify}) {
		$envsave.=<<"EOF"
	if ((s=getenv("ARCH_VERSION")))
		addenv("ARCH_VERSION", s);
EOF
	}
	
	$Data::Dumper::Indent=0; # no newlines
	my $configstring=Data::Dumper->Dump([\%config], ['*config']);
	$configstring=~s/\\/\\\\/g;
	$configstring=~s/"/\\"/g;
	$configstring=~s/\n/\\n/g;
	
	#translators: The first parameter is a filename, and the second is
	#translators: a (probably not translated) error message.
	open(OUT, ">$wrapper.c") || error(sprintf(gettext("failed to write %s: %s"), "$wrapper.c", $!));;
	print OUT <<"EOF";
/* A wrapper for ikiwiki, can be safely made suid. */
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>

extern char **environ;
char *newenviron[$#envsave+5];
int i=0;

addenv(char *var, char *val) {
	char *s=malloc(strlen(var)+1+strlen(val)+1);
	if (!s)
		perror("malloc");
	sprintf(s, "%s=%s", var, val);
	newenviron[i++]=s;
}

int main (int argc, char **argv) {
	/* Sanitize environment. */
	char *s;
$envsave
	newenviron[i++]="HOME=$ENV{HOME}";
	newenviron[i++]="WRAPPED_OPTIONS=$configstring";
	newenviron[i]=NULL;
	environ=newenviron;

	if (setregid(getegid(), -1) != 0 || setreuid(geteuid(), -1) != 0) {
		perror("failed to drop real uid/gid");
		exit(1);
	}

	execl("$this", "$this", NULL);
	perror("exec $this");
	exit(1);
}
EOF
	close OUT;
	if (system("gcc", "$wrapper.c", "-o", "$wrapper.new") != 0) {
		#translators: The parameter is a C filename.
		error(sprintf(gettext("failed to compile %s"), "$wrapper.c"));
	}
	unlink("$wrapper.c");
	if (defined $config{wrappergroup}) {
		my $gid=(getgrnam($config{wrappergroup}))[2];
		if (! defined $gid) {
			error(sprintf("bad wrappergroup"));
		}
		if (! chown(-1, $gid, "$wrapper.new")) {
			error("chown $wrapper.new: $!");
		}
	}
	if (defined $config{wrappermode} &&
	    ! chmod(oct($config{wrappermode}), "$wrapper.new")) {
		error("chmod $wrapper.new: $!");
	}
	if (! rename("$wrapper.new", $wrapper)) {
		error("rename $wrapper.new $wrapper: $!");
	}
	#translators: The parameter is a filename.
	printf(gettext("successfully generated %s"), $wrapper);
	print "\n";
} #}}}

1