Repository navigation
Expand file tree
/
Copy pathmain.go
More file actions
341 lines (316 loc) · 9.08 KB
/
Copy pathmain.go
File metadata and controls
341 lines (316 loc) · 9.08 KB
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
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
package minica
import (
"bytes"
"crypto"
"crypto/rand"
"crypto/rsa"
"crypto/sha1"
"crypto/x509"
"crypto/x509/pkix"
"encoding/asn1"
"encoding/hex"
"encoding/pem"
"flag"
"fmt"
"io/ioutil"
"log"
"math"
"math/big"
"net"
"os"
"regexp"
"strings"
"time"
)
func main() {
err := main2()
if err != nil {
log.Fatal(err)
}
}
type issuer struct {
key crypto.Signer
cert *x509.Certificate
}
func GetIssuer(keyFile, certFile string) (*issuer, error) {
keyContents, keyErr := ioutil.ReadFile(keyFile)
certContents, certErr := ioutil.ReadFile(certFile)
if os.IsNotExist(keyErr) && os.IsNotExist(certErr) {
err := makeIssuer(keyFile, certFile)
if err != nil {
return nil, err
}
return GetIssuer(keyFile, certFile)
} else if keyErr != nil {
return nil, fmt.Errorf("%s (but %s exists)", keyErr, certFile)
} else if certErr != nil {
return nil, fmt.Errorf("%s (but %s exists)", certErr, keyFile)
}
key, err := readPrivateKey(keyContents)
if err != nil {
return nil, fmt.Errorf("reading private key from %s: %s", keyFile, err)
}
cert, err := readCert(certContents)
if err != nil {
return nil, fmt.Errorf("reading CA certificate from %s: %s", certFile, err)
}
equal, err := publicKeysEqual(key.Public(), cert.PublicKey)
if err != nil {
return nil, fmt.Errorf("comparing public keys: %s", err)
} else if !equal {
return nil, fmt.Errorf("public key in CA certificate %s doesn't match private key in %s",
certFile, keyFile)
}
return &issuer{key, cert}, nil
}
func readPrivateKey(keyContents []byte) (crypto.Signer, error) {
block, _ := pem.Decode(keyContents)
if block == nil {
return nil, fmt.Errorf("no PEM found")
} else if block.Type != "RSA PRIVATE KEY" && block.Type != "ECDSA PRIVATE KEY" {
return nil, fmt.Errorf("incorrect PEM type %s", block.Type)
}
return x509.ParsePKCS1PrivateKey(block.Bytes)
}
func readCert(certContents []byte) (*x509.Certificate, error) {
block, _ := pem.Decode(certContents)
if block == nil {
return nil, fmt.Errorf("no PEM found")
} else if block.Type != "CERTIFICATE" {
return nil, fmt.Errorf("incorrect PEM type %s", block.Type)
}
return x509.ParseCertificate(block.Bytes)
}
func makeIssuer(keyFile, certFile string) error {
key, err := makeKey(keyFile)
if err != nil {
return err
}
_, err = makeRootCert(key, certFile)
if err != nil {
return err
}
return nil
}
func makeKey(filename string) (*rsa.PrivateKey, error) {
key, err := rsa.GenerateKey(rand.Reader, 2048)
if err != nil {
return nil, err
}
der := x509.MarshalPKCS1PrivateKey(key)
if err != nil {
return nil, err
}
file, err := os.OpenFile(filename, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0600)
if err != nil {
return nil, err
}
defer file.Close()
err = pem.Encode(file, &pem.Block{
Type: "RSA PRIVATE KEY",
Bytes: der,
})
if err != nil {
return nil, err
}
return key, nil
}
func makeRootCert(key crypto.Signer, filename string) (*x509.Certificate, error) {
serial, err := rand.Int(rand.Reader, big.NewInt(math.MaxInt64))
if err != nil {
return nil, err
}
skid, err := calculateSKID(key.Public())
if err != nil {
return nil, err
}
template := &x509.Certificate{
Subject: pkix.Name{
CommonName: "minica root ca " + hex.EncodeToString(serial.Bytes()[:3]),
},
SerialNumber: serial,
NotBefore: time.Now(),
NotAfter: time.Now().AddDate(100, 0, 0),
SubjectKeyId: skid,
AuthorityKeyId: skid,
KeyUsage: x509.KeyUsageDigitalSignature | x509.KeyUsageCertSign,
ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth, x509.ExtKeyUsageClientAuth},
BasicConstraintsValid: true,
IsCA: true,
MaxPathLenZero: true,
}
der, err := x509.CreateCertificate(rand.Reader, template, template, key.Public(), key)
if err != nil {
return nil, err
}
file, err := os.OpenFile(filename, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0600)
if err != nil {
return nil, err
}
defer file.Close()
err = pem.Encode(file, &pem.Block{
Type: "CERTIFICATE",
Bytes: der,
})
if err != nil {
return nil, err
}
return x509.ParseCertificate(der)
}
func parseIPs(ipAddresses []string) ([]net.IP, error) {
var parsed []net.IP
for _, s := range ipAddresses {
p := net.ParseIP(s)
if p == nil {
return nil, fmt.Errorf("invalid IP address %s", s)
}
parsed = append(parsed, p)
}
return parsed, nil
}
func publicKeysEqual(a, b interface{}) (bool, error) {
aBytes, err := x509.MarshalPKIXPublicKey(a)
if err != nil {
return false, err
}
bBytes, err := x509.MarshalPKIXPublicKey(b)
if err != nil {
return false, err
}
return bytes.Compare(aBytes, bBytes) == 0, nil
}
func calculateSKID(pubKey crypto.PublicKey) ([]byte, error) {
spkiASN1, err := x509.MarshalPKIXPublicKey(pubKey)
if err != nil {
return nil, err
}
var spki struct {
Algorithm pkix.AlgorithmIdentifier
SubjectPublicKey asn1.BitString
}
_, err = asn1.Unmarshal(spkiASN1, &spki)
if err != nil {
return nil, err
}
skid := sha1.Sum(spki.SubjectPublicKey.Bytes)
return skid[:], nil
}
func Sign(iss *issuer, domains []string, ipAddresses []string, cnFolder string) (*x509.Certificate, error) {
var cn string
if len(domains) > 0 {
cn = domains[0]
} else if len(ipAddresses) > 0 {
cn = ipAddresses[0]
} else {
return nil, fmt.Errorf("must specify at least one domain name or IP address")
}
key, err := makeKey(fmt.Sprintf("%s/key.pem", cnFolder))
if err != nil {
return nil, err
}
parsedIPs, err := parseIPs(ipAddresses)
if err != nil {
return nil, err
}
serial, err := rand.Int(rand.Reader, big.NewInt(math.MaxInt64))
if err != nil {
return nil, err
}
template := &x509.Certificate{
DNSNames: domains,
IPAddresses: parsedIPs,
Subject: pkix.Name{
CommonName: cn,
},
SerialNumber: serial,
NotBefore: time.Now(),
// Set the validity period to 2 years and 30 days, to satisfy the iOS and
// macOS requirements that all server certificates must have validity
// shorter than 825 days:
// https://derflounder.wordpress.com/2019/06/06/new-tls-security-requirements-for-ios-13-and-macos-catalina-10-15/
NotAfter: time.Now().AddDate(2, 0, 30),
KeyUsage: x509.KeyUsageDigitalSignature | x509.KeyUsageKeyEncipherment,
ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth, x509.ExtKeyUsageClientAuth},
BasicConstraintsValid: true,
IsCA: false,
}
der, err := x509.CreateCertificate(rand.Reader, template, iss.cert, key.Public(), iss.key)
if err != nil {
return nil, err
}
file, err := os.OpenFile(fmt.Sprintf("%s/cert.pem", cnFolder), os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0600)
if err != nil {
return nil, err
}
defer file.Close()
err = pem.Encode(file, &pem.Block{
Type: "CERTIFICATE",
Bytes: der,
})
if err != nil {
return nil, err
}
return x509.ParseCertificate(der)
}
func split(s string) (results []string) {
if len(s) > 0 {
return strings.Split(s, ",")
}
return nil
}
func main2() error {
var caKey = flag.String("ca-key", "minica-key.pem", "Root private key filename, PEM encoded.")
var caCert = flag.String("ca-cert", "minica.pem", "Root certificate filename, PEM encoded.")
var domains = flag.String("domains", "", "Comma separated domain names to include as Server Alternative Names.")
var ipAddresses = flag.String("ip-addresses", "", "Comma separated IP addresses to include as Server Alternative Names.")
flag.Usage = func() {
fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])
fmt.Fprintf(os.Stderr, `
Minica is a simple CA intended for use in situations where the CA operator
also operates each host where a certificate will be used. It automatically
generates both a key and a certificate when asked to produce a certificate.
It does not offer OCSP or CRL services. Minica is appropriate, for instance,
for generating certificates for RPC systems or microservices.
On first run, minica will generate a keypair and a root certificate in the
current directory, and will reuse that same keypair and root certificate
unless they are deleted.
On each run, minica will generate a new keypair and sign an end-entity (leaf)
certificate for that keypair. The certificate will contain a list of DNS names
and/or IP addresses from the command line flags. The key and certificate are
placed in a new directory whose name is chosen as the first domain name from
the certificate, or the first IP address if no domain names are present. It
will not overwrite existing keys or certificates.
`)
flag.PrintDefaults()
}
flag.Parse()
if *domains == "" && *ipAddresses == "" {
flag.Usage()
os.Exit(1)
}
if len(flag.Args()) > 0 {
fmt.Printf("Extra arguments: %s (maybe there are spaces in your domain list?)\n", flag.Args())
os.Exit(1)
}
domainSlice := split(*domains)
domainRe := regexp.MustCompile("^[A-Za-z0-9.*-]+$")
for _, d := range domainSlice {
if !domainRe.MatchString(d) {
fmt.Printf("Invalid domain name %q\n", d)
os.Exit(1)
}
}
ipSlice := split(*ipAddresses)
for _, ip := range ipSlice {
if net.ParseIP(ip) == nil {
fmt.Printf("Invalid IP address %q\n", ip)
os.Exit(1)
}
}
issuer, err := GetIssuer(*caKey, *caCert)
if err != nil {
return err
}
_, err = Sign(issuer, domainSlice, ipSlice, "")
return err
}