diff options
author | Colin Watson <cjwatson@debian.org> | 2011-01-24 11:46:57 +0000 |
---|---|---|
committer | Colin Watson <cjwatson@debian.org> | 2011-01-24 11:46:57 +0000 |
commit | 0970072c89b079b022538e3c366fbfa2c53fc821 (patch) | |
tree | b7024712d74234bb5a8b036ccbc9109e2e211296 /bufec.c | |
parent | 4e8aa4da57000c7bba8e5c49163bc0c0ca383f78 (diff) | |
parent | 478ff799463ca926a8dfbabf058f4e84aaffc65a (diff) |
merge 5.7p1
Diffstat (limited to 'bufec.c')
-rw-r--r-- | bufec.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/bufec.c b/bufec.c new file mode 100644 index 000000000..3dcb49477 --- /dev/null +++ b/bufec.c | |||
@@ -0,0 +1,146 @@ | |||
1 | /* $OpenBSD: bufec.c,v 1.1 2010/08/31 11:54:45 djm Exp $ */ | ||
2 | /* | ||
3 | * Copyright (c) 2010 Damien Miller <djm@mindrot.org> | ||
4 | * | ||
5 | * Permission to use, copy, modify, and distribute this software for any | ||
6 | * purpose with or without fee is hereby granted, provided that the above | ||
7 | * copyright notice and this permission notice appear in all copies. | ||
8 | * | ||
9 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | ||
10 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | ||
11 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR | ||
12 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | ||
13 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | ||
14 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | ||
15 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | ||
16 | */ | ||
17 | |||
18 | #include "includes.h" | ||
19 | |||
20 | #ifdef OPENSSL_HAS_ECC | ||
21 | |||
22 | #include <sys/types.h> | ||
23 | |||
24 | #include <openssl/bn.h> | ||
25 | #include <openssl/ec.h> | ||
26 | |||
27 | #include <string.h> | ||
28 | #include <stdarg.h> | ||
29 | |||
30 | #include "xmalloc.h" | ||
31 | #include "buffer.h" | ||
32 | #include "log.h" | ||
33 | #include "misc.h" | ||
34 | |||
35 | /* | ||
36 | * Maximum supported EC GFp field length is 528 bits. SEC1 uncompressed | ||
37 | * encoding represents this as two bitstring points that should each | ||
38 | * be no longer than the field length, SEC1 specifies a 1 byte | ||
39 | * point type header. | ||
40 | * Being paranoid here may insulate us to parsing problems in | ||
41 | * EC_POINT_oct2point. | ||
42 | */ | ||
43 | #define BUFFER_MAX_ECPOINT_LEN ((528*2 / 8) + 1) | ||
44 | |||
45 | /* | ||
46 | * Append an EC_POINT to the buffer as a string containing a SEC1 encoded | ||
47 | * uncompressed point. Fortunately OpenSSL handles the gory details for us. | ||
48 | */ | ||
49 | int | ||
50 | buffer_put_ecpoint_ret(Buffer *buffer, const EC_GROUP *curve, | ||
51 | const EC_POINT *point) | ||
52 | { | ||
53 | u_char *buf = NULL; | ||
54 | size_t len; | ||
55 | BN_CTX *bnctx; | ||
56 | int ret = -1; | ||
57 | |||
58 | /* Determine length */ | ||
59 | if ((bnctx = BN_CTX_new()) == NULL) | ||
60 | fatal("%s: BN_CTX_new failed", __func__); | ||
61 | len = EC_POINT_point2oct(curve, point, POINT_CONVERSION_UNCOMPRESSED, | ||
62 | NULL, 0, bnctx); | ||
63 | if (len > BUFFER_MAX_ECPOINT_LEN) { | ||
64 | error("%s: giant EC point: len = %lu (max %u)", | ||
65 | __func__, (u_long)len, BUFFER_MAX_ECPOINT_LEN); | ||
66 | goto out; | ||
67 | } | ||
68 | /* Convert */ | ||
69 | buf = xmalloc(len); | ||
70 | if (EC_POINT_point2oct(curve, point, POINT_CONVERSION_UNCOMPRESSED, | ||
71 | buf, len, bnctx) != len) { | ||
72 | error("%s: EC_POINT_point2oct length mismatch", __func__); | ||
73 | goto out; | ||
74 | } | ||
75 | /* Append */ | ||
76 | buffer_put_string(buffer, buf, len); | ||
77 | ret = 0; | ||
78 | out: | ||
79 | if (buf != NULL) { | ||
80 | bzero(buf, len); | ||
81 | xfree(buf); | ||
82 | } | ||
83 | BN_CTX_free(bnctx); | ||
84 | return ret; | ||
85 | } | ||
86 | |||
87 | void | ||
88 | buffer_put_ecpoint(Buffer *buffer, const EC_GROUP *curve, | ||
89 | const EC_POINT *point) | ||
90 | { | ||
91 | if (buffer_put_ecpoint_ret(buffer, curve, point) == -1) | ||
92 | fatal("%s: buffer error", __func__); | ||
93 | } | ||
94 | |||
95 | int | ||
96 | buffer_get_ecpoint_ret(Buffer *buffer, const EC_GROUP *curve, | ||
97 | EC_POINT *point) | ||
98 | { | ||
99 | u_char *buf; | ||
100 | u_int len; | ||
101 | BN_CTX *bnctx; | ||
102 | int ret = -1; | ||
103 | |||
104 | if ((buf = buffer_get_string_ret(buffer, &len)) == NULL) { | ||
105 | error("%s: invalid point", __func__); | ||
106 | return -1; | ||
107 | } | ||
108 | if ((bnctx = BN_CTX_new()) == NULL) | ||
109 | fatal("%s: BN_CTX_new failed", __func__); | ||
110 | if (len > BUFFER_MAX_ECPOINT_LEN) { | ||
111 | error("%s: EC_POINT too long: %u > max %u", __func__, | ||
112 | len, BUFFER_MAX_ECPOINT_LEN); | ||
113 | goto out; | ||
114 | } | ||
115 | if (len == 0) { | ||
116 | error("%s: EC_POINT buffer is empty", __func__); | ||
117 | goto out; | ||
118 | } | ||
119 | if (buf[0] != POINT_CONVERSION_UNCOMPRESSED) { | ||
120 | error("%s: EC_POINT is in an incorrect form: " | ||
121 | "0x%02x (want 0x%02x)", __func__, buf[0], | ||
122 | POINT_CONVERSION_UNCOMPRESSED); | ||
123 | goto out; | ||
124 | } | ||
125 | if (EC_POINT_oct2point(curve, point, buf, len, bnctx) != 1) { | ||
126 | error("buffer_get_bignum2_ret: BN_bin2bn failed"); | ||
127 | goto out; | ||
128 | } | ||
129 | /* EC_POINT_oct2point verifies that the point is on the curve for us */ | ||
130 | ret = 0; | ||
131 | out: | ||
132 | BN_CTX_free(bnctx); | ||
133 | bzero(buf, len); | ||
134 | xfree(buf); | ||
135 | return ret; | ||
136 | } | ||
137 | |||
138 | void | ||
139 | buffer_get_ecpoint(Buffer *buffer, const EC_GROUP *curve, | ||
140 | EC_POINT *point) | ||
141 | { | ||
142 | if (buffer_get_ecpoint_ret(buffer, curve, point) == -1) | ||
143 | fatal("%s: buffer error", __func__); | ||
144 | } | ||
145 | |||
146 | #endif /* OPENSSL_HAS_ECC */ | ||