diff options
Diffstat (limited to 'sshbuf-getput-crypto.c')
-rw-r--r-- | sshbuf-getput-crypto.c | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/sshbuf-getput-crypto.c b/sshbuf-getput-crypto.c new file mode 100644 index 000000000..74351d3e5 --- /dev/null +++ b/sshbuf-getput-crypto.c | |||
@@ -0,0 +1,237 @@ | |||
1 | /* $OpenBSD: sshbuf-getput-crypto.c,v 1.2 2014/06/18 15:42:09 naddy Exp $ */ | ||
2 | /* | ||
3 | * Copyright (c) 2011 Damien Miller | ||
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 | #define SSHBUF_INTERNAL | ||
19 | #include "includes.h" | ||
20 | |||
21 | #include <sys/types.h> | ||
22 | #include <stdlib.h> | ||
23 | #include <stdio.h> | ||
24 | #include <string.h> | ||
25 | |||
26 | #include <openssl/bn.h> | ||
27 | #ifdef OPENSSL_HAS_ECC | ||
28 | # include <openssl/ec.h> | ||
29 | #endif /* OPENSSL_HAS_ECC */ | ||
30 | |||
31 | #include "ssherr.h" | ||
32 | #include "sshbuf.h" | ||
33 | |||
34 | int | ||
35 | sshbuf_get_bignum2(struct sshbuf *buf, BIGNUM *v) | ||
36 | { | ||
37 | const u_char *d; | ||
38 | size_t len; | ||
39 | int r; | ||
40 | |||
41 | if ((r = sshbuf_peek_string_direct(buf, &d, &len)) < 0) | ||
42 | return r; | ||
43 | /* Refuse negative (MSB set) bignums */ | ||
44 | if ((len != 0 && (*d & 0x80) != 0)) | ||
45 | return SSH_ERR_BIGNUM_IS_NEGATIVE; | ||
46 | /* Refuse overlong bignums, allow prepended \0 to avoid MSB set */ | ||
47 | if (len > SSHBUF_MAX_BIGNUM + 1 || | ||
48 | (len == SSHBUF_MAX_BIGNUM + 1 && *d != 0)) | ||
49 | return SSH_ERR_BIGNUM_TOO_LARGE; | ||
50 | if (v != NULL && BN_bin2bn(d, len, v) == NULL) | ||
51 | return SSH_ERR_ALLOC_FAIL; | ||
52 | /* Consume the string */ | ||
53 | if (sshbuf_get_string_direct(buf, NULL, NULL) != 0) { | ||
54 | /* Shouldn't happen */ | ||
55 | SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR")); | ||
56 | SSHBUF_ABORT(); | ||
57 | return SSH_ERR_INTERNAL_ERROR; | ||
58 | } | ||
59 | return 0; | ||
60 | } | ||
61 | |||
62 | int | ||
63 | sshbuf_get_bignum1(struct sshbuf *buf, BIGNUM *v) | ||
64 | { | ||
65 | const u_char *d = sshbuf_ptr(buf); | ||
66 | u_int16_t len_bits; | ||
67 | size_t len_bytes; | ||
68 | |||
69 | /* Length in bits */ | ||
70 | if (sshbuf_len(buf) < 2) | ||
71 | return SSH_ERR_MESSAGE_INCOMPLETE; | ||
72 | len_bits = PEEK_U16(d); | ||
73 | len_bytes = (len_bits + 7) >> 3; | ||
74 | if (len_bytes > SSHBUF_MAX_BIGNUM) | ||
75 | return SSH_ERR_BIGNUM_TOO_LARGE; | ||
76 | if (sshbuf_len(buf) < 2 + len_bytes) | ||
77 | return SSH_ERR_MESSAGE_INCOMPLETE; | ||
78 | if (v != NULL && BN_bin2bn(d + 2, len_bytes, v) == NULL) | ||
79 | return SSH_ERR_ALLOC_FAIL; | ||
80 | if (sshbuf_consume(buf, 2 + len_bytes) != 0) { | ||
81 | SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR")); | ||
82 | SSHBUF_ABORT(); | ||
83 | return SSH_ERR_INTERNAL_ERROR; | ||
84 | } | ||
85 | return 0; | ||
86 | } | ||
87 | |||
88 | #ifdef OPENSSL_HAS_ECC | ||
89 | static int | ||
90 | get_ec(const u_char *d, size_t len, EC_POINT *v, const EC_GROUP *g) | ||
91 | { | ||
92 | /* Refuse overlong bignums */ | ||
93 | if (len == 0 || len > SSHBUF_MAX_ECPOINT) | ||
94 | return SSH_ERR_ECPOINT_TOO_LARGE; | ||
95 | /* Only handle uncompressed points */ | ||
96 | if (*d != POINT_CONVERSION_UNCOMPRESSED) | ||
97 | return SSH_ERR_INVALID_FORMAT; | ||
98 | if (v != NULL && EC_POINT_oct2point(g, v, d, len, NULL) != 1) | ||
99 | return SSH_ERR_INVALID_FORMAT; /* XXX assumption */ | ||
100 | return 0; | ||
101 | } | ||
102 | |||
103 | int | ||
104 | sshbuf_get_ec(struct sshbuf *buf, EC_POINT *v, const EC_GROUP *g) | ||
105 | { | ||
106 | const u_char *d; | ||
107 | size_t len; | ||
108 | int r; | ||
109 | |||
110 | if ((r = sshbuf_peek_string_direct(buf, &d, &len)) < 0) | ||
111 | return r; | ||
112 | if ((r = get_ec(d, len, v, g)) != 0) | ||
113 | return r; | ||
114 | /* Skip string */ | ||
115 | if (sshbuf_get_string_direct(buf, NULL, NULL) != 0) { | ||
116 | /* Shouldn't happen */ | ||
117 | SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR")); | ||
118 | SSHBUF_ABORT(); | ||
119 | return SSH_ERR_INTERNAL_ERROR; | ||
120 | } | ||
121 | return 0; | ||
122 | } | ||
123 | |||
124 | int | ||
125 | sshbuf_get_eckey(struct sshbuf *buf, EC_KEY *v) | ||
126 | { | ||
127 | EC_POINT *pt = EC_POINT_new(EC_KEY_get0_group(v)); | ||
128 | int r; | ||
129 | const u_char *d; | ||
130 | size_t len; | ||
131 | |||
132 | if (pt == NULL) { | ||
133 | SSHBUF_DBG(("SSH_ERR_ALLOC_FAIL")); | ||
134 | return SSH_ERR_ALLOC_FAIL; | ||
135 | } | ||
136 | if ((r = sshbuf_peek_string_direct(buf, &d, &len)) < 0) { | ||
137 | EC_POINT_free(pt); | ||
138 | return r; | ||
139 | } | ||
140 | if ((r = get_ec(d, len, pt, EC_KEY_get0_group(v))) != 0) { | ||
141 | EC_POINT_free(pt); | ||
142 | return r; | ||
143 | } | ||
144 | if (EC_KEY_set_public_key(v, pt) != 1) { | ||
145 | EC_POINT_free(pt); | ||
146 | return SSH_ERR_ALLOC_FAIL; /* XXX assumption */ | ||
147 | } | ||
148 | EC_POINT_free(pt); | ||
149 | /* Skip string */ | ||
150 | if (sshbuf_get_string_direct(buf, NULL, NULL) != 0) { | ||
151 | /* Shouldn't happen */ | ||
152 | SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR")); | ||
153 | SSHBUF_ABORT(); | ||
154 | return SSH_ERR_INTERNAL_ERROR; | ||
155 | } | ||
156 | return 0; | ||
157 | } | ||
158 | #endif /* OPENSSL_HAS_ECC */ | ||
159 | |||
160 | int | ||
161 | sshbuf_put_bignum2(struct sshbuf *buf, const BIGNUM *v) | ||
162 | { | ||
163 | u_char d[SSHBUF_MAX_BIGNUM + 1]; | ||
164 | int len = BN_num_bytes(v), prepend = 0, r; | ||
165 | |||
166 | if (len < 0 || len > SSHBUF_MAX_BIGNUM) | ||
167 | return SSH_ERR_INVALID_ARGUMENT; | ||
168 | *d = '\0'; | ||
169 | if (BN_bn2bin(v, d + 1) != len) | ||
170 | return SSH_ERR_INTERNAL_ERROR; /* Shouldn't happen */ | ||
171 | /* If MSB is set, prepend a \0 */ | ||
172 | if (len > 0 && (d[1] & 0x80) != 0) | ||
173 | prepend = 1; | ||
174 | if ((r = sshbuf_put_string(buf, d + 1 - prepend, len + prepend)) < 0) { | ||
175 | bzero(d, sizeof(d)); | ||
176 | return r; | ||
177 | } | ||
178 | bzero(d, sizeof(d)); | ||
179 | return 0; | ||
180 | } | ||
181 | |||
182 | int | ||
183 | sshbuf_put_bignum1(struct sshbuf *buf, const BIGNUM *v) | ||
184 | { | ||
185 | int r, len_bits = BN_num_bits(v); | ||
186 | size_t len_bytes = (len_bits + 7) / 8; | ||
187 | u_char d[SSHBUF_MAX_BIGNUM], *dp; | ||
188 | |||
189 | if (len_bits < 0 || len_bytes > SSHBUF_MAX_BIGNUM) | ||
190 | return SSH_ERR_INVALID_ARGUMENT; | ||
191 | if (BN_bn2bin(v, d) != (int)len_bytes) | ||
192 | return SSH_ERR_INTERNAL_ERROR; /* Shouldn't happen */ | ||
193 | if ((r = sshbuf_reserve(buf, len_bytes + 2, &dp)) < 0) { | ||
194 | bzero(d, sizeof(d)); | ||
195 | return r; | ||
196 | } | ||
197 | POKE_U16(dp, len_bits); | ||
198 | memcpy(dp + 2, d, len_bytes); | ||
199 | bzero(d, sizeof(d)); | ||
200 | return 0; | ||
201 | } | ||
202 | |||
203 | #ifdef OPENSSL_HAS_ECC | ||
204 | int | ||
205 | sshbuf_put_ec(struct sshbuf *buf, const EC_POINT *v, const EC_GROUP *g) | ||
206 | { | ||
207 | u_char d[SSHBUF_MAX_ECPOINT]; | ||
208 | BN_CTX *bn_ctx; | ||
209 | size_t len; | ||
210 | int ret; | ||
211 | |||
212 | if ((bn_ctx = BN_CTX_new()) == NULL) | ||
213 | return SSH_ERR_ALLOC_FAIL; | ||
214 | if ((len = EC_POINT_point2oct(g, v, POINT_CONVERSION_UNCOMPRESSED, | ||
215 | NULL, 0, bn_ctx)) > SSHBUF_MAX_ECPOINT) { | ||
216 | BN_CTX_free(bn_ctx); | ||
217 | return SSH_ERR_INVALID_ARGUMENT; | ||
218 | } | ||
219 | if (EC_POINT_point2oct(g, v, POINT_CONVERSION_UNCOMPRESSED, | ||
220 | d, len, bn_ctx) != len) { | ||
221 | BN_CTX_free(bn_ctx); | ||
222 | return SSH_ERR_INTERNAL_ERROR; /* Shouldn't happen */ | ||
223 | } | ||
224 | BN_CTX_free(bn_ctx); | ||
225 | ret = sshbuf_put_string(buf, d, len); | ||
226 | bzero(d, len); | ||
227 | return ret; | ||
228 | } | ||
229 | |||
230 | int | ||
231 | sshbuf_put_eckey(struct sshbuf *buf, const EC_KEY *v) | ||
232 | { | ||
233 | return sshbuf_put_ec(buf, EC_KEY_get0_public_key(v), | ||
234 | EC_KEY_get0_group(v)); | ||
235 | } | ||
236 | #endif /* OPENSSL_HAS_ECC */ | ||
237 | |||