1 #include "internal/quic_vlint.h"
2 #include "internal/e_os.h"
3
4 #ifndef OPENSSL_NO_QUIC
5
ossl_quic_vlint_encode_n(uint8_t * buf,uint64_t v,int n)6 void ossl_quic_vlint_encode_n(uint8_t *buf, uint64_t v, int n)
7 {
8 if (n == 1) {
9 buf[0] = (uint8_t)v;
10 } else if (n == 2) {
11 buf[0] = (uint8_t)(0x40 | ((v >> 8) & 0x3F));
12 buf[1] = (uint8_t)v;
13 } else if (n == 4) {
14 buf[0] = (uint8_t)(0x80 | ((v >> 24) & 0x3F));
15 buf[1] = (uint8_t)(v >> 16);
16 buf[2] = (uint8_t)(v >> 8);
17 buf[3] = (uint8_t)v;
18 } else {
19 buf[0] = (uint8_t)(0xC0 | ((v >> 56) & 0x3F));
20 buf[1] = (uint8_t)(v >> 48);
21 buf[2] = (uint8_t)(v >> 40);
22 buf[3] = (uint8_t)(v >> 32);
23 buf[4] = (uint8_t)(v >> 24);
24 buf[5] = (uint8_t)(v >> 16);
25 buf[6] = (uint8_t)(v >> 8);
26 buf[7] = (uint8_t)v;
27 }
28 }
29
ossl_quic_vlint_encode(uint8_t * buf,uint64_t v)30 void ossl_quic_vlint_encode(uint8_t *buf, uint64_t v)
31 {
32 ossl_quic_vlint_encode_n(buf, v, ossl_quic_vlint_encode_len(v));
33 }
34
ossl_quic_vlint_decode_unchecked(const unsigned char * buf)35 uint64_t ossl_quic_vlint_decode_unchecked(const unsigned char *buf)
36 {
37 uint8_t first_byte = buf[0];
38 size_t sz = ossl_quic_vlint_decode_len(first_byte);
39
40 if (sz == 1)
41 return first_byte & 0x3F;
42
43 if (sz == 2)
44 return ((uint64_t)(first_byte & 0x3F) << 8)
45 | buf[1];
46
47 if (sz == 4)
48 return ((uint64_t)(first_byte & 0x3F) << 24)
49 | ((uint64_t)buf[1] << 16)
50 | ((uint64_t)buf[2] << 8)
51 | buf[3];
52
53 return ((uint64_t)(first_byte & 0x3F) << 56)
54 | ((uint64_t)buf[1] << 48)
55 | ((uint64_t)buf[2] << 40)
56 | ((uint64_t)buf[3] << 32)
57 | ((uint64_t)buf[4] << 24)
58 | ((uint64_t)buf[5] << 16)
59 | ((uint64_t)buf[6] << 8)
60 | buf[7];
61 }
62
ossl_quic_vlint_decode(const unsigned char * buf,size_t buf_len,uint64_t * v)63 int ossl_quic_vlint_decode(const unsigned char *buf, size_t buf_len, uint64_t *v)
64 {
65 size_t dec_len;
66 uint64_t x;
67
68 if (buf_len < 1)
69 return 0;
70
71 dec_len = ossl_quic_vlint_decode_len(buf[0]);
72 if (buf_len < dec_len)
73 return 0;
74
75 x = ossl_quic_vlint_decode_unchecked(buf);
76
77 *v = x;
78 return dec_len;
79 }
80
81 #endif
82
