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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/* LShell 2.01 */
/* Copyright (C) 1995 -- Joel Katz -- Stimpson@Panix.com */
/* Freely Redistributable */
/* Several changes by MM -- Michael Meskes -- meskes@informatik.rwth-aachen.de */
#include <stdio.h>
#include <stdlib.h>
#include <pwd.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <unistd.h>
#include <string.h>
#include <stdio.h>
#ifndef CONFIG_FILE
#define CONFIG_FILE "/etc/lshell.conf"
#endif
#ifndef SHELL_DIR
#define SHELL_DIR "/bin/shells/"
#endif
/* #define EXEMPT_ROOT */
char *strip(char *ptr)
{ /* return ptr if ptr contains no '/' otherwise return pointer */
/* to first character after ptr */
char *ptr2;
char buf[256];
buf[0]='/';
strcpy(buf+1,ptr);
ptr2=buf+strlen(buf)-1;
while(*ptr2!='/') ptr2--;
return ptr+(ptr2-buf);
}
void process(char *buf)
{
char *pp;
/* We are passed a string of the form [Fw][Px][Cy][Dz] where */
/* X is the max number of processes, Y is the max number of */
/* cpu minutes and Z is the max number of megabytes of virtual memory */
/* W is the max number of open files */
int i;
struct rlimit rlim;
pp=buf;
while(*pp!=0)
{
int i;
switch(*pp++)
{
case 'f':
case 'F': i=atoi(pp);
if(!i) break;
rlim.rlim_cur=i;
rlim.rlim_max=i;
setrlimit(RLIMIT_NOFILE,&rlim);
break;
case 'p':
case 'P': i=atoi(pp);
if(!i) break;
rlim.rlim_cur=i;
rlim.rlim_max=i;
setrlimit(RLIMIT_NPROC,&rlim);
break;
case 'c':
case 'C': i=atoi(pp);
if(!i) break;
i*=60;
rlim.rlim_cur=i;
rlim.rlim_max=i;
setrlimit(RLIMIT_CPU,&rlim);
break;
case 'd':
case 'D': i=atoi(pp);
if(!i) break;
i*=1024*1024;
rlim.rlim_cur=i;
rlim.rlim_max=i;
setrlimit(RLIMIT_DATA,&rlim);
break;
}
}
}
void set_em(char *unm)
{
FILE *fil;
int i;
char buf[1024],name[1024],limits[1024];
fil=fopen(CONFIG_FILE,"r");
if(fil==NULL)
{
return;
}
while(fgets(buf,1024,fil)!=NULL)
{
i=sscanf(buf,"%s %s",name,limits);
if(!strcmp(name,unm))
{
if(i==2) process(limits);
fclose(fil);
return;
}
}
fclose(fil);
process(limits); /* Last line is default */
}
void main(int argc, char *argv[], char *environ[])
{
int i;
char *ptr, **nargv, *shell;
#if 0
char full[64];
#endif
struct passwd *j;
char **env;
/* correct SHELL environment variable and learn who we are MM */
/* (HS) Behaviour like the `old' lshell, but w/o destroying the
* environment. (The `old' lshell destroyed the TERM environment,
* under some cirumstances. */
ptr = getenv("SHELL");
if (ptr) {
shell = strdup(ptr);
if (ptr = strstr(shell, "/lshells")) {
i = strlen("/lshells");
memmove(ptr, ptr + i, 1 + strlen(shell) - i - (ptr - shell));
}
setenv("SHELL", shell, 1);
} else shell = NULL;
if (argv[0][0]=='-')
{ /* We are a login shell */
j=getpwuid(getuid());
ptr=j->pw_name;
#ifdef EXEMPT_ROOT
if(strcmp(ptr,"root"))
#endif
if(ptr!=NULL)
set_em(ptr);
#if 0 /* original code */
strcpy(full,SHELL_DIR);
strcat(full,strip(argv[0]+1));
#endif
}
else
{
/* We aren't a login shell
/* We need to assemble our new name and pass our parameters */
#if 0 /* original code */
strcpy(full,SHELL_DIR);
strcat(full,strip(argv[0]));
#endif
}
nargv=malloc((argc+1)*sizeof(char *));
for(i=1; i<argc; i++) nargv[i]=argv[i];
nargv[argc]=NULL; /* argv is not null terminated :-( */
nargv[0]=strip(argv[0]);
#if 0 /* original code */
execv(full,(char **) nargv);
#endif
execve(shell,(char **) nargv, environ);
fprintf(stderr, "Shell %s does not exist. Falling back to sh.\n",shell);
execve("/bin/sh",(char **) nargv, environ);
}
|
