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
|
/*
nsswitch.c - functions for parsing /etc/nsswitch.conf
Copyright (C) 2011 Arthur de Jong
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
#include "config.h"
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include "common.h"
#include "log.h"
/* the maximum line length supported of nsswitch.conf */
#define MAX_LINE_LENGTH 4096
/* TODO: store mtime of file and use it to check reparse */
/* TODO: cache entries for x minutes */
/* see if the line is a service definition for db and return a pointer to
the beginning of the services list if it is */
static const char *find_db(const char *line,const char *db)
{
int i;
i=strlen(db);
/* the line should begin with the db we're looking for */
if (strncmp(line,db,i)!=0)
return NULL;
/* followed by a : */
while (isspace(line[i])) i++;
if (line[i]!=':')
return NULL;
i++;
while (isspace(line[i])) i++;
return line+i;
}
/* check to see if the list of services contains the specified service */
static int has_service(const char *services,const char *service,
const char *filename,int lnr)
{
int i=0,l;
if (services==NULL)
return 0;
l=strlen(service);
while (services[i]!='\0')
{
/* skip spaces */
while (isspace(services[i])) i++;
/* check if this is the service */
if ((strncmp(services+i,service,l)==0)&&(!isalnum(services[i+l])))
return 1;
/* skip service name and spaces */
i++;
while (isalnum(services[i])) i++;
while (isspace(services[i])) i++;
/* skip action mappings */
if (services[i]=='[')
{
i++; /* skip [ */
while ((services[i]!=']')&&(services[i]!='\0')) i++;
if (services[i]!=']')
{
log_log(LOG_WARNING,"%s: error parsing line %d",filename,lnr);
return 0; /* parse error */
}
i++; /* skip ] */
}
}
return 0;
}
int nsswitch_db_uses_ldap(const char *filename,const char *db)
{
FILE *fp;
int lnr=0;
char linebuf[MAX_LINE_LENGTH];
const char *services;
/* open config file */
if ((fp=fopen(filename,"r"))==NULL)
{
log_log(LOG_ERR,"cannot open %s: %s",filename,strerror(errno));
return 0;
}
/* read file and parse lines */
while (fgets(linebuf,sizeof(linebuf),fp)!=NULL)
{
lnr++;
services=find_db(linebuf,db);
if ((services!=NULL)&&has_service(services,"ldap",filename,lnr))
{
fclose(fp);
return 1;
}
}
fclose(fp);
return 0;
}
|