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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
#!/bin/sh
# Wrapper around openssl to generate self-signed X.509 server
# certificates or Certificate Signing Requests, or DKIM private keys.
# Inspired from make-ssl-cert(8) and opendkim-genkey(8).
#
# Copyright © 2014 Guilhem Moulin <guilhem@fripost.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
set -ue
PATH=/usr/bin:/bin
# Default values
type=rsa
bits=
hash=
force=0
config=
pubkey=pubkey.pem
privkey=privkey.pem
dns=
ou=
cn=
usage=
mode=
owner=
group=
rand=
usage() {
cat >&2 <<- EOF
Usage: $0 command [OPTIONS]
Command:
x509: generate a self-signed X.509 server certificate
csr: generate a Certificate Signing Request
dkim: generate a private key (to use for DKIM signing)
Options:
-t type: key type (default: rsa)
-b bits: key length or EC curve (default: 2048 for RSA, 1024 for DSA, secp224r1 for ECDSA)
-h digest: digest algorithm
--ou: organizational Unit Name; can be repeated
--cn: common Name (default: \$(hostname --fqdn)
--dns: hostname for AltName; can be repeated
-f: force; can be repeated (0: don't overwrite, default;
1: reuse private key if it exists;
2: overwrite both keys if they exist)
--config: configuration file
--pubkey: public key file (default: pubkey.pem)
--privkey: private key file (default: privkey.pem)
--usage: key usage (default: digitalSignature,keyEncipherment,keyCertSign)
--mode: set privkey's permission mode (default: 0600)
--owner: set privkey's owner (default: the process' current owner)
--group: set privkey's group (default: the process' current group)
Return values:
0 The key pair was successfully generated
1 The public or private key file exists, and -f is not set
2 The key generation failed
EOF
}
dkiminfo() {
echo "Add the following TXT record to your DNS zone:"
echo "${cn:-$(date +%Y%m%d)}._domainkey\tIN\tTXT ( "
# See https://tools.ietf.org/html/rfc4871#section-3.6.1
# t=s: the "i=" domain in signature headers MUST NOT be a subdomain of "d="
# s=email: limit DKIM signing to email
openssl pkey -pubout <"$privkey" | sed '/^--.*--$/d' \
| { echo -n "v=DKIM1; k=$type; t=s; s=email; p="; tr -d '\n'; } \
| fold -w 250 \
| { sed 's/.*/\t"&"/'; echo ' )'; }
}
[ $# -gt 0 ] || { usage; exit 2; }
cmd="$1"; shift
case "$cmd" in
x509|csr|dkim) ;;
*) echo "Unrecognized command: $cmd" >&2; exit 2
esac
nou=1
while [ $# -gt 0 ]; do
case "$1" in
-t) shift; type="$1";;
-t*) type="${1#-t}";;
-b) shift; bits="$1";;
-b*) bits="${1#-b}";;
-h) shift; hash="$1";;
-h*) hash="${1#-h}";;
--dns=?*) dns="${dns:+$dns, }DNS:${1#--dns=}";;
--cn=?*) cn="${1#--cn=}";;
--ou=?*) ou="${ou:+$ou\n}$nou.organizationalUnitName = ${1#--ou=}"
nou=$(( 1 + $nou ));;
-f) force=$(( 1 + $force ));;
--pubkey=?*) pubkey="${1#--pubkey=}";;
--privkey=?*) privkey="${1#--privkey=}";;
--usage=?*) usage="${usage:+$usage,}${1#--usage=}";;
--config=?*) config="${1#--config=}";;
--mode=?*) mode="${1#--mode=}";;
--owner=?*) owner="${1#--owner=}";;
--group=?*) group="${1#--group=}";;
--help) usage; exit;;
*) echo "Unrecognized argument: $1" >&2; exit 2
esac
shift;
done
case "$type" in
# XXX: genrsa and dsaparam have been deprecated in favor of genpkey.
# genpkey can also create explicit EC parameters, but not named.
rsa) genkey=genrsa; genkeyargs="-f4 ${bits:-2048}";;
dsa) genkey=dsaparam; genkeyargs="-noout -genkey ${bits:-1024}";;
# See 'openssl ecparam -list_curves' for the list of supported
# curves. StrongSwan doesn't support explicit curve parameters
# (however explicit parameters might be required to make exotic
# curves work with some clients.)
ecdsa) genkey=ecparam
genkeyargs="-noout -name ${bits:-secp224r1} -param_enc named_curve -genkey";;
*) echo "Unrecognized key type: $type" >&2; exit 2
esac
if [ "$cmd" = x509 -o "$cmd" = csr ]; then
case "$hash" in
md5|rmd160|sha1|sha224|sha256|sha384|sha512|'') ;;
*) echo "Invalid digest algorithm: $hash" >&2; exit 2;
esac
[ "$cn" ] || cn="$(hostname --fqdn)"
[ ${#cn} -le 64 ] || { echo "CommonName too long: $cn" >&2; exit 2; }
fi
if [ -z "$config" -a \( "$cmd" = x509 -o "$cmd" = csr \) ]; then
config=$(mktemp) || exit 2
trap 'rm -f "$config"' EXIT
# see /usr/share/ssl-cert/ssleay.cnf
cat >"$config" <<- EOF
[ req ]
distinguished_name = req_distinguished_name
prompt = no
policy = policy_anything
req_extensions = v3_req
x509_extensions = v3_req
[ req_distinguished_name ]
organizationName = Fripost
organizationalUnitName = SSLcerts
$(echo "$ou")
commonName = ${cn:-/}
[ v3_req ]
subjectAltName = email:admin@fripost.org${dns:+, $dns}
basicConstraints = critical, CA:FALSE
# https://security.stackexchange.com/questions/24106/which-key-usages-are-required-by-each-key-exchange-method
keyUsage = critical, ${usage:-digitalSignature, keyEncipherment, keyCertSign}
subjectKeyIdentifier = hash
EOF
fi
if [ -s "$privkey" -a $force -eq 0 ]; then
echo "Error: private key exists: $privkey" >&2
[ "$cmd" = dkim ] && dkiminfo
exit 1
elif [ ! -s "$privkey" -o $force -ge 2 ]; then
install --mode="${mode:-0600}" ${owner:+--owner="$owner"} ${group:+--group="$group"} /dev/null "$privkey" || exit 2
openssl $genkey -rand "${rand:-/dev/urandom}" $genkeyargs >"$privkey" || exit 2
[ "$cmd" = dkim ] && { dkiminfo; exit; }
fi
if [ "$cmd" = x509 -a "$pubkey" = "$privkey" ]; then
pubkey=$(mktemp)
openssl req -config "$config" -new -x509 ${hash:+-$hash} -days 3650 -key "$privkey" >"$pubkey" || exit 2
cat "$pubkey" >>"$privkey" || exit 2
rm -f "$pubkey"
elif [ "$cmd" = x509 -o "$cmd" = csr ]; then
if [ -s "$pubkey" -a $force -eq 0 ]; then
echo "Error: public key exists: $pubkey" >&2
exit 1
else
[ "$cmd" = x509 ] && x509=-x509 || x509=
openssl req -config "$config" -new $x509 ${hash:+-$hash} -days 3650 -key "$privkey" >"$pubkey" || exit 2
fi
fi
|
