~vorlon/ubuntu/yakkety/shim-signed/trunk

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
#!/bin/sh
set -e
#set -x

if  test $# = 0                                                 \
    && test x"$SHIM_NOTRIGGER" = x                              \
 && test x"$DPKG_MAINTSCRIPT_PACKAGE" != x                      \
 && dpkg-trigger --check-supported 2>/dev/null
then
        if dpkg-trigger --no-await shim-secureboot-policy; then
                if test x"$SHIM_TRIGGER_DEBUG" != x; then
                        echo "shim: wrapper deferring policy update (trigger activated)"
                fi
                exit 0
        fi
fi

. /usr/share/debconf/confmodule

setup_mok_validation()
{
    local sb_enabled moksb moksbstatert
    local efivars secureboot_var moksb_var moksbstatert_var
    local enable_sb action
    enable_sb=$1
    efivars=/sys/firmware/efi/efivars
    secureboot_var=SecureBoot-8be4df61-93ca-11d2-aa0d-00e098032b8c
    moksb_var=MokSB-605dab50-e046-4300-abb6-3dd810dd8b23
    moksbstatert_var=MokSBStateRT-605dab50-e046-4300-abb6-3dd810dd8b23
    action=disable

    if [ $enable_sb -eq 1 ]; then
        action=enable
    fi

    if [ -d $efivars ] && [ -f $efivars/$secureboot_var ]; then
        sb_enabled=$(od -An -t u1 $efivars/$secureboot_var | awk '{ print $NF; }')
        moksb=0
        moksbstatert=0
        if [ -f $efivars/$moksb_var ]; then
            # if MokSB exists we've likely already run mokutil since last boot
            moksb=1
        fi
        if [ -f /proc/sys/kernel/moksbstate_disabled ]; then
            moksbstatert=$(cat /proc/sys/kernel/moksbstate_disabled 2>/dev/null || echo 0)
        elif [ -f $efivars/$moksbstatert_var ]; then
            # MokSBStateRT set to 1 means validation is disabled
            moksbstatert=$(od -An -t u1 $efivars/$moksbstatert_var | \
                           awk '{ print $NF; }')
        fi
        if [ $sb_enabled -eq 1 ]; then
            if [ $moksb -eq 0 ] && [ $moksbstatert -eq 0 ] || [ $enable_sb -eq 1 ]; then
                STATE=1
                db_settitle shim/title/secureboot
                while true; do
                    case "$STATE" in
                    1)
                        db_capb
                        db_fset shim/secureboot_explanation seen false
                        db_input critical shim/secureboot_explanation || true
                        db_go

                        # Allow the user to skip disabling Secure Boot.
                        db_fset shim/${action}_secureboot seen false
                        db_input critical shim/${action}_secureboot || true
                        ;;
                    2)
                        db_get shim/${action}_secureboot
                        if [ "$RET" = "false" ]; then
                            break
                        fi

                        db_input critical shim/secureboot_key || true
                        db_input critical shim/secureboot_key_again || true
                        ;;
                    3)
                        db_get shim/secureboot_key
                        key="$RET"
                        db_get shim/secureboot_key_again
                        again="$RET"

                        db_capb
                        if [ "$key" != "$again" ]; then
                            db_fset shim/error/secureboot_key_mismatch seen false
                            db_input critical shim/error/secureboot_key_mismatch || true
                            STATE=$(($STATE - 2))
                        else
                            length=$((`echo "$key" | wc -c` - 1))
                            if [ $length -lt 8 ] || [ $length -gt 16 ]; then
                                db_fset shim/error/bad_secureboot_key seen false
                                db_input critical shim/error/bad_secureboot_key || true
                                STATE=$(($STATE - 2))
                            elif [ $length -ne 0 ]; then
                                printf '%s\n%s\n' "$key" "$again" | mokutil --${action}-validation >/dev/null || true
                            fi
                        fi

                        # Always clear secureboot key.
                        db_set shim/secureboot_key ''
                        db_fset shim/secureboot_key seen false
                        db_set shim/secureboot_key_again ''
                        db_fset shim/secureboot_key_again seen false
                        ;;
                    *)
                        break
                        ;;
                    esac;

                    if db_go; then
                        STATE=$(($STATE + 1))
                    else
                        STATE=$(($STATE - 1))
                    fi
                    db_capb backup
                done
                db_capb
            fi
        fi
    fi
}

args=$@
enable_secureboot=0

if echo "$args" | grep -qc -- '--enable'; then
	enable_secureboot=1
elif echo "$args" | grep -qc -- '--disable'; then
	enable_secureboot=0
elif echo "$args" | grep -qc -- '--help'; then
	echo "update-secureboot-policy: toggle UEFI Secure Boot in shim"
	echo
	echo "\t--enable\tPrompt to enable Secure Boot validation."
	echo "\t--disable\tPrompt to disable Secure Boot validation (default)."
	echo "\t--help\t\tThis help text."
	exit 0
fi

if [ `find /var/lib/dkms -type d -print | wc -l ` -gt 1 ]; then
	setup_mok_validation $enable_secureboot
else
	echo "No DKMS packages installed: not changing Secure Boot validation state."
fi

exit 0