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
|
// +build !without_openssl
package stupidgcm
import (
"fmt"
"log"
)
/*
#include "openssl_aead.h"
#cgo pkg-config: libcrypto
*/
import "C"
func openSSLSeal(a *stupidAEADCommon, dst, iv, in, authData []byte) []byte {
if a.Wiped() {
panic("BUG: tried to use wiped key")
}
if len(iv) != a.NonceSize() {
log.Panicf("Only %d-byte IVs are supported, you passed %d bytes", a.NonceSize(), len(iv))
}
if len(in) == 0 {
log.Panic("Zero-length input data is not supported")
}
// If the "dst" slice is large enough we can use it as our output buffer
outLen := len(in) + tagLen
var buf []byte
inplace := false
if cap(dst)-len(dst) >= outLen {
inplace = true
buf = dst[len(dst) : len(dst)+outLen]
} else {
buf = make([]byte, outLen)
}
res := int(C.openssl_aead_seal(a.openSSLEVPCipher,
(*C.uchar)(&in[0]),
C.int(len(in)),
(*C.uchar)(&authData[0]),
C.int(len(authData)),
(*C.uchar)(&a.key[0]),
C.int(len(a.key)),
(*C.uchar)(&iv[0]),
C.int(len(iv)),
(*C.uchar)(&buf[0]),
C.int(len(buf))))
if res != outLen {
log.Panicf("expected length %d, got %d", outLen, res)
}
if inplace {
return dst[:len(dst)+outLen]
}
return append(dst, buf...)
}
func openSSLOpen(a *stupidAEADCommon, dst, iv, in, authData []byte) ([]byte, error) {
if a.Wiped() {
panic("BUG: tried to use wiped key")
}
if len(iv) != a.NonceSize() {
log.Panicf("Only %d-byte IVs are supported, you passed %d bytes", a.NonceSize(), len(iv))
}
if len(in) <= tagLen {
return nil, fmt.Errorf("stupidChacha20poly1305: input data too short (%d bytes)", len(in))
}
// If the "dst" slice is large enough we can use it as our output buffer
outLen := len(in) - tagLen
var buf []byte
inplace := false
if cap(dst)-len(dst) >= outLen {
inplace = true
buf = dst[len(dst) : len(dst)+outLen]
} else {
buf = make([]byte, len(in)-tagLen)
}
ciphertext := in[:len(in)-tagLen]
tag := in[len(in)-tagLen:]
res := int(C.openssl_aead_open(a.openSSLEVPCipher,
(*C.uchar)(&ciphertext[0]),
C.int(len(ciphertext)),
(*C.uchar)(&authData[0]),
C.int(len(authData)),
(*C.uchar)(&tag[0]),
C.int(len(tag)),
(*C.uchar)(&a.key[0]),
C.int(len(a.key)),
(*C.uchar)(&iv[0]),
C.int(len(iv)),
(*C.uchar)(&buf[0]),
C.int(len(buf))))
if res < 0 {
return nil, ErrAuth
}
if res != outLen {
log.Panicf("unexpected length %d", res)
}
if inplace {
return dst[:len(dst)+outLen], nil
}
return append(dst, buf...), nil
}
|
