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mirror of https://git.tartarus.org/simon/putty.git synced 2025-01-09 09:27:59 +00:00
putty-source/testcrypt.h
Simon Tatham 7751657811 Reject all low-order points in Montgomery key exchange.
This expands our previous check for the public value being zero, to
take in all the values that will _become_ zero after not many steps.

The actual check at run time is done using the new is_infinite query
method for Montgomery curve points. Test cases in cryptsuite.py cover
all the dangerous values I generated via all that fiddly quartic-
solving code.

(DJB's page http://cr.yp.to/ecdh.html#validate also lists these same
constants. But working them out again for myself makes me confident I
can do it again for other similar curves, such as Curve448.)

In particular, this makes us fully compliant with RFC 7748's demand to
check we didn't generate a trivial output key, which can happen if the
other end sends any of those low-order values.

I don't actually see why this is a vital check to perform for security
purposes, for the same reason that we didn't classify the bug
'diffie-hellman-range-check' as a vulnerability: I can't really see
what the other end's incentive might be to deliberately send one of
these nonsense values (and you can't do it by accident - none of these
values is a power of the canonical base point). It's not that a DH
participant couldn't possible want to secretly expose the session
traffic - but there are plenty of more subtle (and less subtle!) ways
to do it, so you don't really gain anything by forcing them to use one
of those instead. But the RFC says to check, so we check.
2020-02-28 20:48:52 +00:00

303 lines
15 KiB
C

/*
* mpint.h functions.
*/
FUNC1(val_mpint, mp_new, uint)
FUNC1(void, mp_clear, val_mpint)
FUNC1(val_mpint, mp_from_bytes_le, val_string_ptrlen)
FUNC1(val_mpint, mp_from_bytes_be, val_string_ptrlen)
FUNC1(val_mpint, mp_from_integer, uint)
FUNC1(val_mpint, mp_from_decimal_pl, val_string_ptrlen)
FUNC1(val_mpint, mp_from_decimal, val_string_asciz)
FUNC1(val_mpint, mp_from_hex_pl, val_string_ptrlen)
FUNC1(val_mpint, mp_from_hex, val_string_asciz)
FUNC1(val_mpint, mp_copy, val_mpint)
FUNC1(val_mpint, mp_power_2, uint)
FUNC2(uint, mp_get_byte, val_mpint, uint)
FUNC2(uint, mp_get_bit, val_mpint, uint)
FUNC3(void, mp_set_bit, val_mpint, uint, uint)
FUNC1(uint, mp_max_bytes, val_mpint)
FUNC1(uint, mp_max_bits, val_mpint)
FUNC1(uint, mp_get_nbits, val_mpint)
FUNC1(val_string_asciz, mp_get_decimal, val_mpint)
FUNC1(val_string_asciz, mp_get_hex, val_mpint)
FUNC1(val_string_asciz, mp_get_hex_uppercase, val_mpint)
FUNC2(uint, mp_cmp_hs, val_mpint, val_mpint)
FUNC2(uint, mp_cmp_eq, val_mpint, val_mpint)
FUNC2(uint, mp_hs_integer, val_mpint, uint)
FUNC2(uint, mp_eq_integer, val_mpint, uint)
FUNC3(void, mp_min_into, val_mpint, val_mpint, val_mpint)
FUNC3(void, mp_max_into, val_mpint, val_mpint, val_mpint)
FUNC2(val_mpint, mp_min, val_mpint, val_mpint)
FUNC2(val_mpint, mp_max, val_mpint, val_mpint)
FUNC2(void, mp_copy_into, val_mpint, val_mpint)
FUNC4(void, mp_select_into, val_mpint, val_mpint, val_mpint, uint)
FUNC3(void, mp_add_into, val_mpint, val_mpint, val_mpint)
FUNC3(void, mp_sub_into, val_mpint, val_mpint, val_mpint)
FUNC3(void, mp_mul_into, val_mpint, val_mpint, val_mpint)
FUNC2(val_mpint, mp_add, val_mpint, val_mpint)
FUNC2(val_mpint, mp_sub, val_mpint, val_mpint)
FUNC2(val_mpint, mp_mul, val_mpint, val_mpint)
FUNC3(void, mp_and_into, val_mpint, val_mpint, val_mpint)
FUNC3(void, mp_or_into, val_mpint, val_mpint, val_mpint)
FUNC3(void, mp_xor_into, val_mpint, val_mpint, val_mpint)
FUNC3(void, mp_bic_into, val_mpint, val_mpint, val_mpint)
FUNC3(void, mp_add_integer_into, val_mpint, val_mpint, uint)
FUNC3(void, mp_sub_integer_into, val_mpint, val_mpint, uint)
FUNC3(void, mp_mul_integer_into, val_mpint, val_mpint, uint)
FUNC4(void, mp_cond_add_into, val_mpint, val_mpint, val_mpint, uint)
FUNC4(void, mp_cond_sub_into, val_mpint, val_mpint, val_mpint, uint)
FUNC3(void, mp_cond_swap, val_mpint, val_mpint, uint)
FUNC2(void, mp_cond_clear, val_mpint, uint)
FUNC4(void, mp_divmod_into, val_mpint, val_mpint, opt_val_mpint, opt_val_mpint)
FUNC2(val_mpint, mp_div, val_mpint, val_mpint)
FUNC2(val_mpint, mp_mod, val_mpint, val_mpint)
FUNC2(void, mp_reduce_mod_2to, val_mpint, uint)
FUNC2(val_mpint, mp_invert_mod_2to, val_mpint, uint)
FUNC2(val_mpint, mp_invert, val_mpint, val_mpint)
FUNC5(void, mp_gcd_into, val_mpint, val_mpint, opt_val_mpint, opt_val_mpint, opt_val_mpint)
FUNC2(val_mpint, mp_gcd, val_mpint, val_mpint)
FUNC2(uint, mp_coprime, val_mpint, val_mpint)
FUNC2(val_modsqrt, modsqrt_new, val_mpint, val_mpint)
/* The modsqrt functions' 'success' pointer becomes a second return value */
FUNC3(val_mpint, mp_modsqrt, val_modsqrt, val_mpint, out_uint)
FUNC1(val_monty, monty_new, val_mpint)
FUNC1(val_mpint, monty_modulus, val_monty)
FUNC1(val_mpint, monty_identity, val_monty)
FUNC3(void, monty_import_into, val_monty, val_mpint, val_mpint)
FUNC2(val_mpint, monty_import, val_monty, val_mpint)
FUNC3(void, monty_export_into, val_monty, val_mpint, val_mpint)
FUNC2(val_mpint, monty_export, val_monty, val_mpint)
FUNC4(void, monty_mul_into, val_monty, val_mpint, val_mpint, val_mpint)
FUNC3(val_mpint, monty_add, val_monty, val_mpint, val_mpint)
FUNC3(val_mpint, monty_sub, val_monty, val_mpint, val_mpint)
FUNC3(val_mpint, monty_mul, val_monty, val_mpint, val_mpint)
FUNC3(val_mpint, monty_pow, val_monty, val_mpint, val_mpint)
FUNC2(val_mpint, monty_invert, val_monty, val_mpint)
FUNC3(val_mpint, monty_modsqrt, val_modsqrt, val_mpint, out_uint)
FUNC3(val_mpint, mp_modpow, val_mpint, val_mpint, val_mpint)
FUNC3(val_mpint, mp_modmul, val_mpint, val_mpint, val_mpint)
FUNC3(val_mpint, mp_modadd, val_mpint, val_mpint, val_mpint)
FUNC3(val_mpint, mp_modsub, val_mpint, val_mpint, val_mpint)
FUNC3(void, mp_lshift_safe_into, val_mpint, val_mpint, uint)
FUNC3(void, mp_rshift_safe_into, val_mpint, val_mpint, uint)
FUNC2(val_mpint, mp_rshift_safe, val_mpint, uint)
FUNC3(void, mp_lshift_fixed_into, val_mpint, val_mpint, uint)
FUNC3(void, mp_rshift_fixed_into, val_mpint, val_mpint, uint)
FUNC2(val_mpint, mp_rshift_fixed, val_mpint, uint)
FUNC1(val_mpint, mp_random_bits, uint)
FUNC2(val_mpint, mp_random_in_range, val_mpint, val_mpint)
/*
* ecc.h functions.
*/
FUNC4(val_wcurve, ecc_weierstrass_curve, val_mpint, val_mpint, val_mpint, opt_val_mpint)
FUNC1(val_wpoint, ecc_weierstrass_point_new_identity, val_wcurve)
FUNC3(val_wpoint, ecc_weierstrass_point_new, val_wcurve, val_mpint, val_mpint)
FUNC3(val_wpoint, ecc_weierstrass_point_new_from_x, val_wcurve, val_mpint, uint)
FUNC1(val_wpoint, ecc_weierstrass_point_copy, val_wpoint)
FUNC1(uint, ecc_weierstrass_point_valid, val_wpoint)
FUNC2(val_wpoint, ecc_weierstrass_add_general, val_wpoint, val_wpoint)
FUNC2(val_wpoint, ecc_weierstrass_add, val_wpoint, val_wpoint)
FUNC1(val_wpoint, ecc_weierstrass_double, val_wpoint)
FUNC2(val_wpoint, ecc_weierstrass_multiply, val_wpoint, val_mpint)
FUNC1(uint, ecc_weierstrass_is_identity, val_wpoint)
/* The output pointers in get_affine all become extra output values */
FUNC3(void, ecc_weierstrass_get_affine, val_wpoint, out_val_mpint, out_val_mpint)
FUNC3(val_mcurve, ecc_montgomery_curve, val_mpint, val_mpint, val_mpint)
FUNC2(val_mpoint, ecc_montgomery_point_new, val_mcurve, val_mpint)
FUNC1(val_mpoint, ecc_montgomery_point_copy, val_mpoint)
FUNC3(val_mpoint, ecc_montgomery_diff_add, val_mpoint, val_mpoint, val_mpoint)
FUNC1(val_mpoint, ecc_montgomery_double, val_mpoint)
FUNC2(val_mpoint, ecc_montgomery_multiply, val_mpoint, val_mpint)
FUNC2(void, ecc_montgomery_get_affine, val_mpoint, out_val_mpint)
FUNC1(boolean, ecc_montgomery_is_identity, val_mpoint)
FUNC4(val_ecurve, ecc_edwards_curve, val_mpint, val_mpint, val_mpint, opt_val_mpint)
FUNC3(val_epoint, ecc_edwards_point_new, val_ecurve, val_mpint, val_mpint)
FUNC3(val_epoint, ecc_edwards_point_new_from_y, val_ecurve, val_mpint, uint)
FUNC1(val_epoint, ecc_edwards_point_copy, val_epoint)
FUNC2(val_epoint, ecc_edwards_add, val_epoint, val_epoint)
FUNC2(val_epoint, ecc_edwards_multiply, val_epoint, val_mpint)
FUNC2(uint, ecc_edwards_eq, val_epoint, val_epoint)
FUNC3(void, ecc_edwards_get_affine, val_epoint, out_val_mpint, out_val_mpint)
/*
* The ssh_hash abstraction. Note the 'consumed', indicating that
* ssh_hash_final puts its input ssh_hash beyond use.
*
* ssh_hash_update is an invention of testcrypt, handled in the real C
* API by the hash object also functioning as a BinarySink.
*/
FUNC1(opt_val_hash, ssh_hash_new, hashalg)
FUNC1(void, ssh_hash_reset, val_hash)
FUNC1(val_hash, ssh_hash_copy, val_hash)
FUNC1(val_string, ssh_hash_digest, val_hash)
FUNC1(val_string, ssh_hash_final, consumed_val_hash)
FUNC2(void, ssh_hash_update, val_hash, val_string_ptrlen)
/*
* The ssh2_mac abstraction. Note the optional ssh_cipher parameter
* to ssh2_mac_new. Also, again, I've invented an ssh2_mac_update so
* you can put data into the MAC.
*/
FUNC2(val_mac, ssh2_mac_new, macalg, opt_val_cipher)
FUNC2(void, ssh2_mac_setkey, val_mac, val_string_ptrlen)
FUNC1(void, ssh2_mac_start, val_mac)
FUNC2(void, ssh2_mac_update, val_mac, val_string_ptrlen)
FUNC1(val_string, ssh2_mac_genresult, val_mac)
FUNC1(val_string_asciz_const, ssh2_mac_text_name, val_mac)
/*
* The ssh_key abstraction. All the uses of BinarySink and
* BinarySource in parameters are replaced with ordinary strings for
* the testing API: new_priv_openssh just takes a string input, and
* all the functions that output key and signature blobs do it by
* returning a string.
*/
FUNC2(val_key, ssh_key_new_pub, keyalg, val_string_ptrlen)
FUNC3(opt_val_key, ssh_key_new_priv, keyalg, val_string_ptrlen, val_string_ptrlen)
FUNC2(opt_val_key, ssh_key_new_priv_openssh, keyalg, val_string_binarysource)
FUNC2(opt_val_string_asciz, ssh_key_invalid, val_key, uint)
FUNC4(void, ssh_key_sign, val_key, val_string_ptrlen, uint, out_val_string_binarysink)
FUNC3(boolean, ssh_key_verify, val_key, val_string_ptrlen, val_string_ptrlen)
FUNC2(void, ssh_key_public_blob, val_key, out_val_string_binarysink)
FUNC2(void, ssh_key_private_blob, val_key, out_val_string_binarysink)
FUNC2(void, ssh_key_openssh_blob, val_key, out_val_string_binarysink)
FUNC1(val_string_asciz, ssh_key_cache_str, val_key)
FUNC1(val_keycomponents, ssh_key_components, val_key)
FUNC2(uint, ssh_key_public_bits, keyalg, val_string_ptrlen)
/*
* Accessors to retrieve the innards of a 'key_components'.
*/
FUNC1(uint, key_components_count, val_keycomponents)
FUNC2(opt_val_string_asciz_const, key_components_nth_name, val_keycomponents, uint)
FUNC2(opt_val_string_asciz_const, key_components_nth_str, val_keycomponents, uint)
FUNC2(opt_val_mpint, key_components_nth_mp, val_keycomponents, uint)
/*
* The ssh_cipher abstraction. The in-place encrypt and decrypt
* functions are wrapped to replace them with versions that take one
* string and return a separate string.
*/
FUNC1(opt_val_cipher, ssh_cipher_new, cipheralg)
FUNC2(void, ssh_cipher_setiv, val_cipher, val_string_ptrlen)
FUNC2(void, ssh_cipher_setkey, val_cipher, val_string_ptrlen)
FUNC2(val_string, ssh_cipher_encrypt, val_cipher, val_string_ptrlen)
FUNC2(val_string, ssh_cipher_decrypt, val_cipher, val_string_ptrlen)
FUNC3(val_string, ssh_cipher_encrypt_length, val_cipher, val_string_ptrlen, uint)
FUNC3(val_string, ssh_cipher_decrypt_length, val_cipher, val_string_ptrlen, uint)
/*
* Integer Diffie-Hellman.
*/
FUNC1(val_dh, dh_setup_group, dh_group)
FUNC2(val_dh, dh_setup_gex, val_mpint, val_mpint)
FUNC1(uint, dh_modulus_bit_size, val_dh)
FUNC2(val_mpint, dh_create_e, val_dh, uint)
FUNC2(boolean, dh_validate_f, val_dh, val_mpint)
FUNC2(val_mpint, dh_find_K, val_dh, val_mpint)
/*
* Elliptic-curve Diffie-Hellman.
*/
FUNC1(val_ecdh, ssh_ecdhkex_newkey, ecdh_alg)
FUNC2(void, ssh_ecdhkex_getpublic, val_ecdh, out_val_string_binarysink)
FUNC2(opt_val_mpint, ssh_ecdhkex_getkey, val_ecdh, val_string_ptrlen)
/*
* RSA key exchange, and also the BinarySource get function
* get_ssh1_rsa_priv_agent, which is a convenient way to make an
* RSAKey for RSA kex testing purposes.
*/
FUNC1(val_rsakex, ssh_rsakex_newkey, val_string_ptrlen)
FUNC1(uint, ssh_rsakex_klen, val_rsakex)
FUNC3(val_string, ssh_rsakex_encrypt, val_rsakex, hashalg, val_string_ptrlen)
FUNC3(opt_val_mpint, ssh_rsakex_decrypt, val_rsakex, hashalg, val_string_ptrlen)
FUNC1(val_rsakex, get_rsa_ssh1_priv_agent, val_string_binarysource)
/*
* Bare RSA keys as used in SSH-1. The construction API functions
* write into an existing RSAKey object, so I've invented an 'rsa_new'
* function to make one in the first place.
*/
FUNC0(val_rsa, rsa_new)
FUNC3(void, get_rsa_ssh1_pub, val_string_binarysource, val_rsa, rsaorder)
FUNC2(void, get_rsa_ssh1_priv, val_string_binarysource, val_rsa)
FUNC2(opt_val_string, rsa_ssh1_encrypt, val_string_ptrlen, val_rsa)
FUNC2(val_mpint, rsa_ssh1_decrypt, val_mpint, val_rsa)
FUNC2(val_string, rsa_ssh1_decrypt_pkcs1, val_mpint, val_rsa)
FUNC1(val_string_asciz, rsastr_fmt, val_rsa)
FUNC1(val_string_asciz, rsa_ssh1_fingerprint, val_rsa)
FUNC3(void, rsa_ssh1_public_blob, out_val_string_binarysink, val_rsa, rsaorder)
FUNC1(int, rsa_ssh1_public_blob_len, val_string_ptrlen)
FUNC2(void, rsa_ssh1_private_blob_agent, out_val_string_binarysink, val_rsa)
/*
* The PRNG type. Similarly to hashes and MACs, I've invented an extra
* function prng_seed_update for putting seed data into the PRNG's
* exposed BinarySink.
*/
FUNC1(val_prng, prng_new, hashalg)
FUNC1(void, prng_seed_begin, val_prng)
FUNC2(void, prng_seed_update, val_prng, val_string_ptrlen)
FUNC1(void, prng_seed_finish, val_prng)
FUNC2(val_string, prng_read, val_prng, uint)
FUNC3(void, prng_add_entropy, val_prng, uint, val_string_ptrlen)
/*
* Key load/save functions, or rather, the BinarySource / strbuf API
* that sits just inside the file I/O versions.
*/
FUNC2(boolean, ppk_encrypted_s, val_string_binarysource, out_opt_val_string_asciz)
FUNC2(boolean, rsa1_encrypted_s, val_string_binarysource, out_opt_val_string_asciz)
FUNC5(boolean, ppk_loadpub_s, val_string_binarysource, out_opt_val_string_asciz, out_val_string_binarysink, out_opt_val_string_asciz, out_opt_val_string_asciz_const)
FUNC4(int, rsa1_loadpub_s, val_string_binarysource, out_val_string_binarysink, out_opt_val_string_asciz, out_opt_val_string_asciz_const)
FUNC4(opt_val_key, ppk_load_s, val_string_binarysource, out_opt_val_string_asciz, opt_val_string_asciz, out_opt_val_string_asciz_const)
FUNC5(int, rsa1_load_s, val_string_binarysource, val_rsa, out_opt_val_string_asciz, opt_val_string_asciz, out_opt_val_string_asciz_const)
FUNC3(val_string, ppk_save_sb, val_key, opt_val_string_asciz, opt_val_string_asciz)
FUNC3(val_string, rsa1_save_sb, val_rsa, opt_val_string_asciz, opt_val_string_asciz)
/*
* Key generation functions.
*/
FUNC1(val_key, rsa_generate, uint)
FUNC1(val_key, dsa_generate, uint)
FUNC1(opt_val_key, ecdsa_generate, uint)
FUNC1(opt_val_key, eddsa_generate, uint)
FUNC1(val_rsa, rsa1_generate, uint)
FUNC5(val_mpint, primegen, uint, uint, uint, val_mpint, uint)
FUNC3(val_pcs, pcs_new, uint, uint, uint)
FUNC3(void, pcs_require_residue, val_pcs, val_mpint, val_mpint)
FUNC2(void, pcs_require_residue_1, val_pcs, val_mpint)
FUNC3(void, pcs_avoid_residue_small, val_pcs, uint, uint)
FUNC1(void, pcs_ready, val_pcs)
FUNC4(void, pcs_inspect, val_pcs, out_val_mpint, out_val_mpint, out_val_mpint)
FUNC1(val_mpint, pcs_generate, val_pcs)
/*
* Miscellaneous.
*/
FUNC2(val_wpoint, ecdsa_public, val_mpint, keyalg)
FUNC2(val_epoint, eddsa_public, val_mpint, keyalg)
FUNC2(val_string, des_encrypt_xdmauth, val_string_ptrlen, val_string_ptrlen)
FUNC2(val_string, des_decrypt_xdmauth, val_string_ptrlen, val_string_ptrlen)
FUNC2(val_string, des3_encrypt_pubkey, val_string_ptrlen, val_string_ptrlen)
FUNC2(val_string, des3_decrypt_pubkey, val_string_ptrlen, val_string_ptrlen)
FUNC3(val_string, des3_encrypt_pubkey_ossh, val_string_ptrlen, val_string_ptrlen, val_string_ptrlen)
FUNC3(val_string, des3_decrypt_pubkey_ossh, val_string_ptrlen, val_string_ptrlen, val_string_ptrlen)
FUNC2(val_string, aes256_encrypt_pubkey, val_string_ptrlen, val_string_ptrlen)
FUNC2(val_string, aes256_decrypt_pubkey, val_string_ptrlen, val_string_ptrlen)
FUNC1(uint, crc32_rfc1662, val_string_ptrlen)
FUNC1(uint, crc32_ssh1, val_string_ptrlen)
FUNC2(uint, crc32_update, uint, val_string_ptrlen)
FUNC2(boolean, crcda_detect, val_string_ptrlen, val_string_ptrlen)
/*
* These functions aren't part of PuTTY's own API, but are additions
* by testcrypt itself for administrative purposes.
*/
FUNC1(void, random_queue, val_string_ptrlen)
FUNC0(uint, random_queue_len)
FUNC2(void, random_make_prng, hashalg, val_string_ptrlen)
FUNC0(void, random_clear)