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/dl_group/dl_group.h | |
parent | 9efa3be92442afb3d0b69890a36c7f122df18eda (diff) |
Move lib into src
Diffstat (limited to 'src/lib/pubkey/dl_group/dl_group.h')
-rw-r--r-- | src/lib/pubkey/dl_group/dl_group.h | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/src/lib/pubkey/dl_group/dl_group.h b/src/lib/pubkey/dl_group/dl_group.h new file mode 100644 index 000000000..e219bdcbd --- /dev/null +++ b/src/lib/pubkey/dl_group/dl_group.h @@ -0,0 +1,170 @@ +/* +* Discrete Logarithm Group +* (C) 1999-2008 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#ifndef BOTAN_DL_PARAM_H__ +#define BOTAN_DL_PARAM_H__ + +#include <botan/bigint.h> +#include <botan/data_src.h> + +namespace Botan { + +/** +* This class represents discrete logarithm groups. It holds a prime p, +* a prime q = (p-1)/2 and g = x^((p-1)/q) mod p. +*/ +class BOTAN_DLL DL_Group + { + public: + + /** + * Get the prime p. + * @return prime p + */ + const BigInt& get_p() const; + + /** + * Get the prime q. + * @return prime q + */ + const BigInt& get_q() const; + + /** + * Get the base g. + * @return base g + */ + const BigInt& get_g() const; + + /** + * The DL group encoding format variants. + */ + enum Format { + ANSI_X9_42, + ANSI_X9_57, + PKCS_3, + + DSA_PARAMETERS = ANSI_X9_57, + DH_PARAMETERS = ANSI_X9_42, + X942_DH_PARAMETERS = ANSI_X9_42, + PKCS3_DH_PARAMETERS = PKCS_3 + }; + + /** + * Determine the prime creation for DL groups. + */ + enum PrimeType { Strong, Prime_Subgroup, DSA_Kosherizer }; + + /** + * Perform validity checks on the group. + * @param rng the rng to use + * @param strong whether to perform stronger by lengthier tests + * @return true if the object is consistent, false otherwise + */ + bool verify_group(RandomNumberGenerator& rng, bool strong) const; + + /** + * Encode this group into a string using PEM encoding. + * @param format the encoding format + * @return string holding the PEM encoded group + */ + std::string PEM_encode(Format format) const; + + /** + * Encode this group into a string using DER encoding. + * @param format the encoding format + * @return string holding the DER encoded group + */ + std::vector<byte> DER_encode(Format format) const; + + /** + * Decode a DER/BER encoded group into this instance. + * @param ber a vector containing the DER/BER encoded group + * @param format the format of the encoded group + */ + void BER_decode(const std::vector<byte>& ber, + Format format); + + /** + * Decode a PEM encoded group into this instance. + * @param pem the PEM encoding of the group + */ + void PEM_decode(const std::string& pem); + + /** + * Construct a DL group with uninitialized internal value. + * Use this constructor is you wish to set the groups values + * from a DER or PEM encoded group. + */ + DL_Group(); + + /** + * Construct a DL group that is registered in the configuration. + * @param name the name that is configured in the global configuration + * for the desired group. If no configuration file is specified, + * the default values from the file policy.cpp will be used. For instance, + * use "modp/ietf/768" as name. + */ + DL_Group(const std::string& name); + + /** + * Create a new group randomly. + * @param rng the random number generator to use + * @param type specifies how the creation of primes p and q shall + * be performed. If type=Strong, then p will be determined as a + * safe prime, and q will be chosen as (p-1)/2. If + * type=Prime_Subgroup and qbits = 0, then the size of q will be + * determined according to the estimated difficulty of the DL + * problem. If type=DSA_Kosherizer, DSA primes will be created. + * @param pbits the number of bits of p + * @param qbits the number of bits of q. Leave it as 0 to have + * the value determined according to pbits. + */ + DL_Group(RandomNumberGenerator& rng, PrimeType type, + size_t pbits, size_t qbits = 0); + + /** + * Create a DSA group with a given seed. + * @param rng the random number generator to use + * @param seed the seed to use to create the random primes + * @param pbits the desired bit size of the prime p + * @param qbits the desired bit size of the prime q. + */ + DL_Group(RandomNumberGenerator& rng, + const std::vector<byte>& seed, + size_t pbits = 1024, size_t qbits = 0); + + /** + * Create a DL group. The prime q will be determined according to p. + * @param p the prime p + * @param g the base g + */ + DL_Group(const BigInt& p, const BigInt& g); + + /** + * Create a DL group. + * @param p the prime p + * @param q the prime q + * @param g the base g + */ + DL_Group(const BigInt& p, const BigInt& q, const BigInt& g); + + /** + * Return PEM representation of named DL group + */ + static const char* PEM_for_named_group(const std::string& name); + private: + static BigInt make_dsa_generator(const BigInt&, const BigInt&); + + void init_check() const; + void initialize(const BigInt&, const BigInt&, const BigInt&); + bool initialized; + BigInt p, q, g; + }; + +} + +#endif |