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author | Doug Hogan <[email protected]> | 2018-12-20 02:09:15 -0800 |
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committer | Doug Hogan <[email protected]> | 2018-12-20 02:30:56 -0800 |
commit | 6d6a79ac688001038b7b37f934ead2593507928a (patch) | |
tree | 4803a2015281a9c3c03b254054e11990ef771738 /lib/crypto/c_src/ec.c | |
parent | 121efebb92f81ac4136c63de79fa88b2b6cedfa2 (diff) | |
download | otp-6d6a79ac688001038b7b37f934ead2593507928a.tar.gz otp-6d6a79ac688001038b7b37f934ead2593507928a.tar.bz2 otp-6d6a79ac688001038b7b37f934ead2593507928a.zip |
Move EC functionality to a new file
Diffstat (limited to 'lib/crypto/c_src/ec.c')
-rw-r--r-- | lib/crypto/c_src/ec.c | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/lib/crypto/c_src/ec.c b/lib/crypto/c_src/ec.c new file mode 100644 index 0000000000..4cd710f652 --- /dev/null +++ b/lib/crypto/c_src/ec.c @@ -0,0 +1,340 @@ +#include "ec.h" +#include "bn.h" + +#ifdef HAVE_EC +static EC_KEY* ec_key_new(ErlNifEnv* env, ERL_NIF_TERM curve_arg); +static ERL_NIF_TERM point2term(ErlNifEnv* env, + const EC_GROUP *group, + const EC_POINT *point, + point_conversion_form_t form); + +ERL_NIF_TERM make_badarg_maybe(ErlNifEnv* env) +{ + ERL_NIF_TERM reason; + if (enif_has_pending_exception(env, &reason)) + return reason; /* dummy return value ignored */ + else + return enif_make_badarg(env); +} + +static EC_KEY* ec_key_new(ErlNifEnv* env, ERL_NIF_TERM curve_arg) +{ + EC_KEY *key = NULL; + int c_arity = -1; + const ERL_NIF_TERM* curve; + ErlNifBinary seed; + BIGNUM *p = NULL; + BIGNUM *a = NULL; + BIGNUM *b = NULL; + BIGNUM *bn_order = NULL; + BIGNUM *cofactor = NULL; + EC_GROUP *group = NULL; + EC_POINT *point = NULL; + + /* {Field, Prime, Point, Order, CoFactor} = Curve */ + if (enif_get_tuple(env,curve_arg,&c_arity,&curve) + && c_arity == 5 + && get_bn_from_bin(env, curve[3], &bn_order) + && (curve[4] != atom_none && get_bn_from_bin(env, curve[4], &cofactor))) { + + int f_arity = -1; + const ERL_NIF_TERM* field; + int p_arity = -1; + const ERL_NIF_TERM* prime; + + long field_bits; + + /* {A, B, Seed} = Prime */ + if (!enif_get_tuple(env,curve[1],&p_arity,&prime) + || !get_bn_from_bin(env, prime[0], &a) + || !get_bn_from_bin(env, prime[1], &b)) + goto out_err; + + if (!enif_get_tuple(env,curve[0],&f_arity,&field)) + goto out_err; + + if (f_arity == 2 && field[0] == atom_prime_field) { + /* {prime_field, Prime} */ + + if (!get_bn_from_bin(env, field[1], &p)) + goto out_err; + + if (BN_is_negative(p) || BN_is_zero(p)) + goto out_err; + + field_bits = BN_num_bits(p); + if (field_bits > OPENSSL_ECC_MAX_FIELD_BITS) + goto out_err; + + /* create the EC_GROUP structure */ + group = EC_GROUP_new_curve_GFp(p, a, b, NULL); + + } else if (f_arity == 3 && field[0] == atom_characteristic_two_field) { +#if defined(OPENSSL_NO_EC2M) + enif_raise_exception(env, atom_notsup); + goto out_err; +#else + /* {characteristic_two_field, M, Basis} */ + + int b_arity = -1; + const ERL_NIF_TERM* basis; + unsigned int k1, k2, k3; + + if ((p = BN_new()) == NULL) + goto out_err; + + if (!enif_get_long(env, field[1], &field_bits) + || field_bits > OPENSSL_ECC_MAX_FIELD_BITS) + goto out_err; + + if (enif_get_tuple(env,field[2],&b_arity,&basis)) { + if (b_arity == 2 + && basis[0] == atom_tpbasis + && enif_get_uint(env, basis[1], &k1)) { + /* {tpbasis, k} = Basis */ + + if (!(field_bits > k1 && k1 > 0)) + goto out_err; + + /* create the polynomial */ + if (!BN_set_bit(p, (int)field_bits) + || !BN_set_bit(p, (int)k1) + || !BN_set_bit(p, 0)) + goto out_err; + + } else if (b_arity == 4 + && basis[0] == atom_ppbasis + && enif_get_uint(env, basis[1], &k1) + && enif_get_uint(env, basis[2], &k2) + && enif_get_uint(env, basis[3], &k3)) { + /* {ppbasis, k1, k2, k3} = Basis */ + + if (!(field_bits > k3 && k3 > k2 && k2 > k1 && k1 > 0)) + goto out_err; + + /* create the polynomial */ + if (!BN_set_bit(p, (int)field_bits) + || !BN_set_bit(p, (int)k1) + || !BN_set_bit(p, (int)k2) + || !BN_set_bit(p, (int)k3) + || !BN_set_bit(p, 0)) + goto out_err; + + } else + goto out_err; + } else if (field[2] == atom_onbasis) { + /* onbasis = Basis */ + /* no parameters */ + goto out_err; + + } else + goto out_err; + + group = EC_GROUP_new_curve_GF2m(p, a, b, NULL); +#endif + } else + goto out_err; + + if (!group) + goto out_err; + + if (enif_inspect_binary(env, prime[2], &seed)) { + EC_GROUP_set_seed(group, seed.data, seed.size); + } + + if (!term2point(env, curve[2], group, &point)) + goto out_err; + + if (BN_is_negative(bn_order) + || BN_is_zero(bn_order) + || BN_num_bits(bn_order) > (int)field_bits + 1) + goto out_err; + + if (!EC_GROUP_set_generator(group, point, bn_order, cofactor)) + goto out_err; + + EC_GROUP_set_asn1_flag(group, 0x0); + + key = EC_KEY_new(); + if (!key) + goto out_err; + EC_KEY_set_group(key, group); + } + else { + goto out_err; + } + + + goto out; + +out_err: + if (key) EC_KEY_free(key); + key = NULL; + +out: + /* some OpenSSL structures are mem-dup'ed into the key, + so we have to free our copies here */ + if (p) BN_free(p); + if (a) BN_free(a); + if (b) BN_free(b); + if (bn_order) BN_free(bn_order); + if (cofactor) BN_free(cofactor); + if (group) EC_GROUP_free(group); + if (point) EC_POINT_free(point); + + return key; +} + +static ERL_NIF_TERM point2term(ErlNifEnv* env, + const EC_GROUP *group, + const EC_POINT *point, + point_conversion_form_t form) +{ + unsigned dlen; + ErlNifBinary bin; + + dlen = EC_POINT_point2oct(group, point, form, NULL, 0, NULL); + if (dlen == 0) + return atom_undefined; + + if (!enif_alloc_binary(dlen, &bin)) + return enif_make_badarg(env); + + if (!EC_POINT_point2oct(group, point, form, bin.data, bin.size, NULL)) { + enif_release_binary(&bin); + return enif_make_badarg(env); + } + ERL_VALGRIND_MAKE_MEM_DEFINED(bin.data, bin.size); + return enif_make_binary(env, &bin); +} + +int term2point(ErlNifEnv* env, ERL_NIF_TERM term, EC_GROUP *group, EC_POINT **pptr) +{ + int ret = 0; + ErlNifBinary bin; + EC_POINT *point; + + if (!enif_inspect_binary(env,term,&bin)) { + return 0; + } + + if ((*pptr = point = EC_POINT_new(group)) == NULL) { + return 0; + } + + /* set the point conversion form */ + EC_GROUP_set_point_conversion_form(group, (point_conversion_form_t)(bin.data[0] & ~0x01)); + + /* extract the ec point */ + if (!EC_POINT_oct2point(group, point, bin.data, bin.size, NULL)) { + EC_POINT_free(point); + *pptr = NULL; + } else + ret = 1; + + return ret; +} + +int get_ec_key(ErlNifEnv* env, + ERL_NIF_TERM curve, ERL_NIF_TERM priv, ERL_NIF_TERM pub, + EC_KEY** res) +{ + EC_KEY *key = NULL; + BIGNUM *priv_key = NULL; + EC_POINT *pub_key = NULL; + EC_GROUP *group = NULL; + + if (!(priv == atom_undefined || get_bn_from_bin(env, priv, &priv_key)) + || !(pub == atom_undefined || enif_is_binary(env, pub))) { + goto out_err; + } + + key = ec_key_new(env, curve); + + if (!key) { + goto out_err; + } + + if (!group) + group = EC_GROUP_dup(EC_KEY_get0_group(key)); + + if (term2point(env, pub, group, &pub_key)) { + if (!EC_KEY_set_public_key(key, pub_key)) { + goto out_err; + } + } + if (priv != atom_undefined + && !BN_is_zero(priv_key)) { + if (!EC_KEY_set_private_key(key, priv_key)) + goto out_err; + + /* calculate public key (if necessary) */ + if (EC_KEY_get0_public_key(key) == NULL) + { + /* the public key was not included in the SEC1 private + * key => calculate the public key */ + pub_key = EC_POINT_new(group); + if (pub_key == NULL + || !EC_POINT_copy(pub_key, EC_GROUP_get0_generator(group)) + || !EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, NULL) + || !EC_KEY_set_public_key(key, pub_key)) + goto out_err; + } + } + + goto out; + +out_err: + if (key) EC_KEY_free(key); + key = NULL; + +out: + /* some OpenSSL structures are mem-dup'ed into the key, + so we have to free our copies here */ + if (priv_key) BN_clear_free(priv_key); + if (pub_key) EC_POINT_free(pub_key); + if (group) EC_GROUP_free(group); + if (!key) + return 0; + *res = key; + return 1; +} + +#endif /* HAVE_EC */ + +ERL_NIF_TERM ec_key_generate(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) +{ +#if defined(HAVE_EC) + EC_KEY *key = NULL; + const EC_GROUP *group; + const EC_POINT *public_key; + ERL_NIF_TERM priv_key; + ERL_NIF_TERM pub_key = atom_undefined; + + if (!get_ec_key(env, argv[0], argv[1], atom_undefined, &key)) + goto badarg; + + if (argv[1] == atom_undefined) { + if (!EC_KEY_generate_key(key)) + goto badarg; + } + + group = EC_KEY_get0_group(key); + public_key = EC_KEY_get0_public_key(key); + + if (group && public_key) { + pub_key = point2term(env, group, public_key, + EC_KEY_get_conv_form(key)); + } + priv_key = bn2term(env, EC_KEY_get0_private_key(key)); + EC_KEY_free(key); + return enif_make_tuple2(env, pub_key, priv_key); + +badarg: + if (key) + EC_KEY_free(key); + return make_badarg_maybe(env); +#else + return atom_notsup; +#endif +} |