diff options
| -rw-r--r-- | src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c | 18 | ||||
| -rw-r--r-- | src/libstrongswan/plugins/openssl/openssl_util.c | 15 |
2 files changed, 24 insertions, 9 deletions
diff --git a/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c b/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c index c93acb75c..4c5d3f294 100644 --- a/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c +++ b/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c @@ -108,7 +108,8 @@ error: * Convert an EC_POINT to a chunk by concatenating the x and y coordinates of * the point. This function allocates memory for the chunk. */ -static bool ecp2chunk(const EC_GROUP *group, const EC_POINT *point, chunk_t *chunk) +static bool ecp2chunk(const EC_GROUP *group, const EC_POINT *point, + chunk_t *chunk, bool x_coordinate_only) { BN_CTX *ctx; BIGNUM *x, *y; @@ -133,6 +134,10 @@ static bool ecp2chunk(const EC_GROUP *group, const EC_POINT *point, chunk_t *chu goto error; } + if (x_coordinate_only) + { + y = NULL; + } if (!openssl_bn_cat(EC_FIELD_ELEMENT_LEN(group), x, y, chunk)) { goto error; @@ -160,7 +165,7 @@ static bool compute_shared_key(private_openssl_ec_diffie_hellman_t *this, chunk_ { const BIGNUM *priv_key; EC_POINT *secret = NULL; - bool ret = FALSE; + bool x_coordinate_only, ret = FALSE; priv_key = EC_KEY_get0_private_key(this->key); if (!priv_key) @@ -179,7 +184,12 @@ static bool compute_shared_key(private_openssl_ec_diffie_hellman_t *this, chunk_ goto error; } - if (!ecp2chunk(this->ec_group, secret, shared_secret)) + /* + * x_coordinate_only = TRUE applies errata for RFC 4753 + */ + x_coordinate_only = lib->settings->get_bool(lib->settings, + "libstrongswan.ecp_x_coordinate_only", FALSE); + if (!ecp2chunk(this->ec_group, secret, shared_secret, x_coordinate_only)) { goto error; } @@ -219,7 +229,7 @@ static void set_other_public_value(private_openssl_ec_diffie_hellman_t *this, ch */ static void get_my_public_value(private_openssl_ec_diffie_hellman_t *this,chunk_t *value) { - ecp2chunk(this->ec_group, EC_KEY_get0_public_key(this->key), value); + ecp2chunk(this->ec_group, EC_KEY_get0_public_key(this->key), value, FALSE); } /** diff --git a/src/libstrongswan/plugins/openssl/openssl_util.c b/src/libstrongswan/plugins/openssl/openssl_util.c index bb0c296e1..c8c453f64 100644 --- a/src/libstrongswan/plugins/openssl/openssl_util.c +++ b/src/libstrongswan/plugins/openssl/openssl_util.c @@ -71,21 +71,26 @@ bool openssl_bn_cat(int len, BIGNUM *a, BIGNUM *b, chunk_t *chunk) { int offset; - chunk->len = len * 2; + chunk->len = len + (b ? len : 0); chunk->ptr = malloc(chunk->len); memset(chunk->ptr, 0, chunk->len); + /* convert a */ offset = len - BN_num_bytes(a); if (!BN_bn2bin(a, chunk->ptr + offset)) { goto error; } - offset = len - BN_num_bytes(b); - if (!BN_bn2bin(b, chunk->ptr + len + offset)) + /* optionally convert and concatenate b */ + if (b) { - goto error; - } + offset = len - BN_num_bytes(b); + if (!BN_bn2bin(b, chunk->ptr + len + offset)) + { + goto error; + } + } return TRUE; error: |