diff options
author | lloyd <[email protected]> | 2014-01-10 03:41:59 +0000 |
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committer | lloyd <[email protected]> | 2014-01-10 03:41:59 +0000 |
commit | 6894dca64c04936d07048c0e8cbf7e25858548c3 (patch) | |
tree | 5d572bfde9fe667dab14e3f04b5285a85d8acd95 /src/lib/pubkey/rsa/rsa.cpp | |
parent | 9efa3be92442afb3d0b69890a36c7f122df18eda (diff) |
Move lib into src
Diffstat (limited to 'src/lib/pubkey/rsa/rsa.cpp')
-rw-r--r-- | src/lib/pubkey/rsa/rsa.cpp | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/src/lib/pubkey/rsa/rsa.cpp b/src/lib/pubkey/rsa/rsa.cpp new file mode 100644 index 000000000..199ce6ad8 --- /dev/null +++ b/src/lib/pubkey/rsa/rsa.cpp @@ -0,0 +1,121 @@ +/* +* RSA +* (C) 1999-2010 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#include <botan/rsa.h> +#include <botan/parsing.h> +#include <botan/numthry.h> +#include <botan/keypair.h> +#include <future> + +namespace Botan { + +/* +* Create a RSA private key +*/ +RSA_PrivateKey::RSA_PrivateKey(RandomNumberGenerator& rng, + size_t bits, size_t exp) + { + if(bits < 1024) + throw Invalid_Argument(algo_name() + ": Can't make a key that is only " + + std::to_string(bits) + " bits long"); + if(exp < 3 || exp % 2 == 0) + throw Invalid_Argument(algo_name() + ": Invalid encryption exponent"); + + e = exp; + + do + { + p = random_prime(rng, (bits + 1) / 2, e); + q = random_prime(rng, bits - p.bits(), e); + n = p * q; + } while(n.bits() != bits); + + d = inverse_mod(e, lcm(p - 1, q - 1)); + d1 = d % (p - 1); + d2 = d % (q - 1); + c = inverse_mod(q, p); + + gen_check(rng); + } + +/* +* Check Private RSA Parameters +*/ +bool RSA_PrivateKey::check_key(RandomNumberGenerator& rng, bool strong) const + { + if(!IF_Scheme_PrivateKey::check_key(rng, strong)) + return false; + + if(!strong) + return true; + + if((e * d) % lcm(p - 1, q - 1) != 1) + return false; + + return KeyPair::signature_consistency_check(rng, *this, "EMSA4(SHA-1)"); + } + +RSA_Private_Operation::RSA_Private_Operation(const RSA_PrivateKey& rsa, + RandomNumberGenerator& rng) : + n(rsa.get_n()), + q(rsa.get_q()), + c(rsa.get_c()), + powermod_e_n(rsa.get_e(), rsa.get_n()), + powermod_d1_p(rsa.get_d1(), rsa.get_p()), + powermod_d2_q(rsa.get_d2(), rsa.get_q()), + mod_p(rsa.get_p()) + { + BigInt k(rng, n.bits() - 1); + blinder = Blinder(powermod_e_n(k), inverse_mod(k, n), n); + } + +BigInt RSA_Private_Operation::private_op(const BigInt& m) const + { + if(m >= n) + throw Invalid_Argument("RSA private op - input is too large"); + + auto future_j1 = std::async(std::launch::async, powermod_d1_p, m); + BigInt j2 = powermod_d2_q(m); + BigInt j1 = future_j1.get(); + + j1 = mod_p.reduce(sub_mul(j1, j2, c)); + + return mul_add(j1, q, j2); + } + +secure_vector<byte> +RSA_Private_Operation::sign(const byte msg[], size_t msg_len, + RandomNumberGenerator& rng) + { + rng.add_entropy(msg, msg_len); + + /* We don't check signatures against powermod_e_n here because + PK_Signer checks verification consistency for all signature + algorithms. + */ + + const BigInt m(msg, msg_len); + const BigInt x = blinder.unblind(private_op(blinder.blind(m))); + return BigInt::encode_1363(x, n.bytes()); + } + +/* +* RSA Decryption Operation +*/ +secure_vector<byte> +RSA_Private_Operation::decrypt(const byte msg[], size_t msg_len) + { + const BigInt m(msg, msg_len); + const BigInt x = blinder.unblind(private_op(blinder.blind(m))); + + BOTAN_ASSERT(m == powermod_e_n(x), + "RSA decrypt passed consistency check"); + + return BigInt::encode_locked(x); + } + +} |