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authorDr. Stephen Henson <steve@openssl.org>2011-12-10 13:35:11 +0000
committerDr. Stephen Henson <steve@openssl.org>2013-10-01 14:01:18 +0100
commit3e792793f6bd74e3a753c1b104417ba2b162f4f5 (patch)
treed21e0c9409b51fa38aa07bbc9caf272e02b2a3d7 /crypto/ecdh
parentac5cb33356962409acf8ddf334831cf5de6cc2aa (diff)
add cofactor ECDH support from fips branch
(cherry picked from commit a3a2e3a43d13d8486c5e100e1bef7fec8e61b27b)
Diffstat (limited to 'crypto/ecdh')
-rw-r--r--crypto/ecdh/ecdh.h2
-rw-r--r--crypto/ecdh/ech_ossl.c12
2 files changed, 14 insertions, 0 deletions
diff --git a/crypto/ecdh/ecdh.h b/crypto/ecdh/ecdh.h
index 98c6cdf9be..6d792180d6 100644
--- a/crypto/ecdh/ecdh.h
+++ b/crypto/ecdh/ecdh.h
@@ -85,6 +85,8 @@
extern "C" {
#endif
+#define EC_FLAG_COFACTOR_ECDH 0x1000
+
const ECDH_METHOD *ECDH_OpenSSL(void);
void ECDH_set_default_method(const ECDH_METHOD *);
diff --git a/crypto/ecdh/ech_ossl.c b/crypto/ecdh/ech_ossl.c
index 4a30628fbc..fa98eb11ce 100644
--- a/crypto/ecdh/ech_ossl.c
+++ b/crypto/ecdh/ech_ossl.c
@@ -137,6 +137,18 @@ static int ecdh_compute_key(void *out, size_t outlen, const EC_POINT *pub_key,
}
group = EC_KEY_get0_group(ecdh);
+
+ if (EC_KEY_get_flags(ecdh) & EC_FLAG_COFACTOR_ECDH)
+ {
+ if (!EC_GROUP_get_cofactor(group, x, ctx) ||
+ !BN_mul(x, x, priv_key, ctx))
+ {
+ ECDHerr(ECDH_F_ECDH_COMPUTE_KEY, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+ priv_key = x;
+ }
+
if ((tmp=EC_POINT_new(group)) == NULL)
{
ECDHerr(ECDH_F_ECDH_COMPUTE_KEY,ERR_R_MALLOC_FAILURE);