forked from andres-erbsen/voteserver
/
reg-server.go
133 lines (119 loc) · 2.75 KB
/
reg-server.go
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
// Written by Andres Erbsen, distributed under GPLv3
package main
import (
"bytes"
"crypto"
"crypto/rand"
"crypto/rsa"
"crypto/sha256"
"crypto/x509"
"encoding/binary"
"encoding/pem"
"fmt"
"io"
"io/ioutil"
"net/http"
"os"
"path/filepath"
)
const LSAGS_PK_SIZE = 29
var server_sk *rsa.PrivateKey
func statusHandler(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("REG"))
}
func regHandler(w http.ResponseWriter, r *http.Request) {
if r.Method != "POST" {
return
}
r.Body = http.MaxBytesReader(w, r.Body, 1024)
postdata, err := ioutil.ReadAll(r.Body)
if err != nil {
return
}
buf := bytes.NewBuffer(postdata)
var voter_id uint64
if binary.Read(buf, binary.LittleEndian, &voter_id) != nil {
return
}
var voucher_type uint8
if binary.Read(buf, binary.LittleEndian, &voucher_type) != nil {
return
}
var sig_len uint16
if binary.Read(buf, binary.LittleEndian, &sig_len) != nil {
return
}
if int(sig_len+LSAGS_PK_SIZE) > len(postdata) {
return
}
sig := make([]byte, sig_len)
_, err = io.ReadFull(buf, sig)
if err != nil {
return
}
pk := make([]byte, LSAGS_PK_SIZE)
_, err = io.ReadFull(buf, pk)
if err != nil {
return
}
cargo, err := ioutil.ReadAll(buf)
if err != nil {
return
}
sig_type := x509.SignatureAlgorithm(voucher_type)
voter_file := filepath.Join("voters", fmt.Sprintf("%d", voter_id))
cert_der, err := ioutil.ReadFile(voter_file + ".cer")
if err != nil {
return
}
cert, err := x509.ParseCertificate(cert_der)
if err != nil {
return
}
if cert.CheckSignature(sig_type, pk, sig) != nil {
return
}
if ioutil.WriteFile(voter_file+".sig", sig, os.FileMode(0600)) != nil {
return
}
if ioutil.WriteFile(voter_file+".pk", pk, os.FileMode(0600)) != nil {
return
}
if ioutil.WriteFile(voter_file+".cargo", cargo, os.FileMode(0600)) != nil {
return
}
h := sha256.New()
if _, err := h.Write([]byte("REGISTER")); err != nil {
return
}
if _, err := h.Write(postdata); err != nil {
return
}
server_sig, err := rsa.SignPKCS1v15(rand.Reader, server_sk, crypto.SHA256, h.Sum(nil))
if err != nil {
return
}
w.Write(server_sig)
ioutil.WriteFile(voter_file+".reg", postdata, os.FileMode(0600))
fmt.Println(voter_id, "registered successfully")
}
func main() {
if len(os.Args) != 2 {
panic("usage: vote-server.go SECRETKEY_FILE")
}
server_sk_raw, err := ioutil.ReadFile(os.Args[1])
if err != nil {
panic(err)
}
server_sk_pem, _ := pem.Decode(server_sk_raw)
if server_sk_pem == nil {
panic("No PEM block in server secret key file?")
}
server_sk, err = x509.ParsePKCS1PrivateKey(server_sk_pem.Bytes)
if err != nil {
panic(err)
}
http.HandleFunc("/status", statusHandler)
http.HandleFunc("/register", regHandler)
panic(http.ListenAndServeTLS(":10443", "cert.pem", os.Args[1], nil))
}