1 | /* |
2 | * Copyright 2002-2018 The OpenSSL Project Authors. All Rights Reserved. |
3 | * |
4 | * Licensed under the Apache License 2.0 (the "License"). You may not use |
5 | * this file except in compliance with the License. You can obtain a copy |
6 | * in the file LICENSE in the source distribution or at |
7 | * https://www.openssl.org/source/license.html |
8 | */ |
9 | |
10 | #include <openssl/crypto.h> |
11 | #include <openssl/err.h> |
12 | #include "ec_local.h" |
13 | |
14 | BIGNUM *EC_POINT_point2bn(const EC_GROUP *group, |
15 | const EC_POINT *point, |
16 | point_conversion_form_t form, |
17 | BIGNUM *ret, BN_CTX *ctx) |
18 | { |
19 | size_t buf_len = 0; |
20 | unsigned char *buf; |
21 | |
22 | buf_len = EC_POINT_point2buf(group, point, form, &buf, ctx); |
23 | |
24 | if (buf_len == 0) |
25 | return NULL; |
26 | |
27 | ret = BN_bin2bn(buf, buf_len, ret); |
28 | |
29 | OPENSSL_free(buf); |
30 | |
31 | return ret; |
32 | } |
33 | |
34 | EC_POINT *EC_POINT_bn2point(const EC_GROUP *group, |
35 | const BIGNUM *bn, EC_POINT *point, BN_CTX *ctx) |
36 | { |
37 | size_t buf_len = 0; |
38 | unsigned char *buf; |
39 | EC_POINT *ret; |
40 | |
41 | if ((buf_len = BN_num_bytes(bn)) == 0) |
42 | buf_len = 1; |
43 | if ((buf = OPENSSL_malloc(buf_len)) == NULL) { |
44 | ECerr(EC_F_EC_POINT_BN2POINT, ERR_R_MALLOC_FAILURE); |
45 | return NULL; |
46 | } |
47 | |
48 | if (!BN_bn2binpad(bn, buf, buf_len)) { |
49 | OPENSSL_free(buf); |
50 | return NULL; |
51 | } |
52 | |
53 | if (point == NULL) { |
54 | if ((ret = EC_POINT_new(group)) == NULL) { |
55 | OPENSSL_free(buf); |
56 | return NULL; |
57 | } |
58 | } else |
59 | ret = point; |
60 | |
61 | if (!EC_POINT_oct2point(group, ret, buf, buf_len, ctx)) { |
62 | if (ret != point) |
63 | EC_POINT_clear_free(ret); |
64 | OPENSSL_free(buf); |
65 | return NULL; |
66 | } |
67 | |
68 | OPENSSL_free(buf); |
69 | return ret; |
70 | } |
71 | |
72 | static const char *HEX_DIGITS = "0123456789ABCDEF" ; |
73 | |
74 | /* the return value must be freed (using OPENSSL_free()) */ |
75 | char *EC_POINT_point2hex(const EC_GROUP *group, |
76 | const EC_POINT *point, |
77 | point_conversion_form_t form, BN_CTX *ctx) |
78 | { |
79 | char *ret, *p; |
80 | size_t buf_len = 0, i; |
81 | unsigned char *buf = NULL, *pbuf; |
82 | |
83 | buf_len = EC_POINT_point2buf(group, point, form, &buf, ctx); |
84 | |
85 | if (buf_len == 0) |
86 | return NULL; |
87 | |
88 | ret = OPENSSL_malloc(buf_len * 2 + 2); |
89 | if (ret == NULL) { |
90 | OPENSSL_free(buf); |
91 | return NULL; |
92 | } |
93 | p = ret; |
94 | pbuf = buf; |
95 | for (i = buf_len; i > 0; i--) { |
96 | int v = (int)*(pbuf++); |
97 | *(p++) = HEX_DIGITS[v >> 4]; |
98 | *(p++) = HEX_DIGITS[v & 0x0F]; |
99 | } |
100 | *p = '\0'; |
101 | |
102 | OPENSSL_free(buf); |
103 | |
104 | return ret; |
105 | } |
106 | |
107 | EC_POINT *EC_POINT_hex2point(const EC_GROUP *group, |
108 | const char *buf, EC_POINT *point, BN_CTX *ctx) |
109 | { |
110 | EC_POINT *ret = NULL; |
111 | BIGNUM *tmp_bn = NULL; |
112 | |
113 | if (!BN_hex2bn(&tmp_bn, buf)) |
114 | return NULL; |
115 | |
116 | ret = EC_POINT_bn2point(group, tmp_bn, point, ctx); |
117 | |
118 | BN_clear_free(tmp_bn); |
119 | |
120 | return ret; |
121 | } |
122 | |