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
|
From: Harald van Dijk <harald@gigawatt.nl>
Date: Thu, 22 Aug 2013 21:59:36 +0200
Subject: Implement privmode, part 2
Origin: http://article.gmane.org/gmane.comp.security.oss.general/10972
---
src/Makefile.am | 2 +-
src/dash.1 | 2 +-
src/main.c | 14 +-------------
src/options.c | 4 +++-
src/priv.c | 27 +++++++++++++++++++++++++++
src/priv.h | 6 ++++++
src/var.c | 3 ---
7 files changed, 39 insertions(+), 19 deletions(-)
create mode 100644 src/priv.c
create mode 100644 src/priv.h
diff --git a/src/Makefile.am b/src/Makefile.am
index 2c437bb..50d5a5b 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -20,7 +20,7 @@ bin_PROGRAMS = dash
dash_CFILES = \
alias.c arith_yacc.c arith_yylex.c cd.c error.c eval.c exec.c expand.c \
histedit.c input.c jobs.c mail.c main.c memalloc.c miscbltin.c \
- mystring.c options.c parser.c redir.c show.c trap.c output.c \
+ mystring.c options.c parser.c priv.c redir.c show.c trap.c output.c \
bltin/printf.c system.c bltin/test.c bltin/times.c var.c
dash_SOURCES = \
$(dash_CFILES) \
diff --git a/src/dash.1 b/src/dash.1
index 6c62245..d1b960a 100644
--- a/src/dash.1
+++ b/src/dash.1
@@ -257,7 +257,7 @@ if it has been set).
.It Fl b Em notify
Enable asynchronous notification of background job completion.
(UNIMPLEMENTED for 4.4alpha)
-.It Fl p Em nopriv
+.It Fl p Em priviliged
Do not attempt to reset effective uid if it does not match uid. This is not set
by default to help avoid incorrect usage by setuid root programs via system(3) or
popen(3).
diff --git a/src/main.c b/src/main.c
index 83f0514..a9ac77d 100644
--- a/src/main.c
+++ b/src/main.c
@@ -50,6 +50,7 @@
#include "eval.h"
#include "jobs.h"
#include "input.h"
+#include "priv.h"
#include "trap.h"
#include "var.h"
#include "show.h"
@@ -93,8 +94,6 @@ main(int argc, char **argv)
volatile int state;
struct stackmark smark;
int login;
- uid_t uid;
- gid_t gid;
#ifdef __GLIBC__
dash_errno = __errno_location();
@@ -152,17 +151,6 @@ main(int argc, char **argv)
setstackmark(&smark);
login = procargs(argc, argv);
- /*
- * To limit bogus system(3) or popen(3) calls in setuid binaries, require
- * -p flag to work in this situation.
- */
- if (!pflag && (uid != geteuid() || gid != getegid())) {
- setuid(uid);
- setgid(gid);
- /* PS1 might need to be changed accordingly. */
- choose_ps1();
- }
-
if (login) {
state = 1;
read_profile("/etc/profile");
diff --git a/src/options.c b/src/options.c
index 48502bb..edc66e3 100644
--- a/src/options.c
+++ b/src/options.c
@@ -45,6 +45,7 @@
#include "jobs.h"
#include "input.h"
#include "output.h"
+#include "priv.h"
#include "trap.h"
#include "var.h"
#include "memalloc.h"
@@ -79,7 +80,7 @@ static const char *const optnames[NOPTS] = {
"allexport",
"notify",
"nounset",
- "nopriv",
+ "privileged",
"nolog",
"debug",
};
@@ -183,6 +184,7 @@ optschanged(void)
#ifdef DEBUG
opentrace();
#endif
+ setprivileged(pflag);
setinteractive(iflag);
#ifndef SMALL
histedit();
diff --git a/src/priv.c b/src/priv.c
new file mode 100644
index 0000000..26346c0
--- /dev/null
+++ b/src/priv.c
@@ -0,0 +1,27 @@
+#include <unistd.h>
+
+#include "priv.h"
+#include "var.h"
+
+uid_t uid;
+gid_t gid;
+
+void setprivileged(int on)
+{
+ static int is_privileged = 1;
+ if (is_privileged == on)
+ return;
+
+ is_privileged = on;
+
+ /*
+ * To limit bogus system(3) or popen(3) calls in setuid binaries, require
+ * -p flag to work in this situation.
+ */
+ if (!on && (uid != geteuid() || gid != getegid())) {
+ setuid(uid);
+ setgid(gid);
+ /* PS1 might need to be changed accordingly. */
+ choose_ps1();
+ }
+}
diff --git a/src/priv.h b/src/priv.h
new file mode 100644
index 0000000..31b380b
--- /dev/null
+++ b/src/priv.h
@@ -0,0 +1,6 @@
+#include <unistd.h>
+
+extern uid_t uid;
+extern gid_t gid;
+
+void setprivileged(int on);
diff --git a/src/var.c b/src/var.c
index 35334bc..c7e7d2e 100644
--- a/src/var.c
+++ b/src/var.c
@@ -188,9 +188,6 @@ initvar(void)
void
choose_ps1(void)
{
- if (vps1.flags & VEXPORT)
- return;
-
if (!geteuid()) {
vps1.text = rootps1;
} else {
|
