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Diffstat (limited to 'src/backend/taler_signatures.h')
| -rw-r--r-- | src/backend/taler_signatures.h | 653 |
1 files changed, 0 insertions, 653 deletions
diff --git a/src/backend/taler_signatures.h b/src/backend/taler_signatures.h deleted file mode 100644 index 402e67fe..00000000 --- a/src/backend/taler_signatures.h +++ /dev/null @@ -1,653 +0,0 @@ -/* - This file is part of TALER - Copyright (C) 2014, 2015 Christian Grothoff (and other contributing authors) - - TALER is free software; you can redistribute it and/or modify it under the - terms of the GNU General Public License as published by the Free Software - Foundation; either version 3, or (at your option) any later version. - - TALER is distributed in the hope that it will be useful, but WITHOUT ANY - WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR - A PARTICULAR PURPOSE. See the GNU General Public License for more details. - - You should have received a copy of the GNU General Public License along with - TALER; see the file COPYING. If not, If not, see <http://www.gnu.org/licenses/> -*/ -/** - * @file taler_signatures.h - * @brief message formats and signature constants used to define - * the binary formats of signatures in Taler - * @author Florian Dold - * @author Benedikt Mueller - * - * This file should define the constants and C structs that one needs - * to know to implement Taler clients (wallets or merchants or - * auditor) that need to produce or verify Taler signatures. - */ - -#ifndef TALER_SIGNATURES_H -#define TALER_SIGNATURES_H - -#if HAVE_GNUNET_GNUNET_UTIL_LIB_H -#include <gnunet/gnunet_util_lib.h> -#elif HAVE_GNUNET_GNUNET_UTIL_TALER_WALLET_LIB_H -#include <gnunet/gnunet_util_taler_wallet_lib.h> -#endif - -#include "taler_amount_lib.h" -#include "taler_crypto_lib.h" - -/** - * Cut-and-choose size for refreshing. Client looses the gamble (of - * unaccountable transfers) with probability 1/TALER_CNC_KAPPA. Refresh cost - * increases linearly with TALER_CNC_KAPPA, and 3 is sufficient up to a - * income/sales tax of 66% of total transaction value. As there is - * no good reason to change this security parameter, we declare it - * fixed and part of the protocol. - */ -#define TALER_CNC_KAPPA 3 - -/** - * After what time do idle reserves "expire"? We might want to make - * this a configuration option (eventually). - */ -#define TALER_IDLE_RESERVE_EXPIRATION_TIME GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_YEARS, 5) - -/*********************************************/ -/* Mint offline signatures (with master key) */ -/*********************************************/ - -/** - * Purpose for signing public keys signed by the mint master key. - */ -#define TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY 1024 - -/** - * Purpose for denomination keys signed by the mint master key. - */ -#define TALER_SIGNATURE_MASTER_DENOMINATION_KEY_VALIDITY 1025 - - -/*********************************************/ -/* Mint online signatures (with signing key) */ -/*********************************************/ - -/** - * Purpose for the state of a reserve, signed by the mint's signing - * key. - */ -#define TALER_SIGNATURE_MINT_RESERVE_STATUS 1032 - -/** - * Signature where the Mint confirms a deposit request. - */ -#define TALER_SIGNATURE_MINT_CONFIRM_DEPOSIT 1033 - -/** - * Signature where the mint (current signing key) confirms the - * no-reveal index for cut-and-choose and the validity of the melted - * coins. - */ -#define TALER_SIGNATURE_MINT_CONFIRM_MELT 1034 - -/** - * Signature where the Mint confirms the full /keys response set. - */ -#define TALER_SIGNATURE_MINT_KEY_SET 1035 - - -/*********************/ -/* Wallet signatures */ -/*********************/ - -/** - * Signature where the auditor confirms that he is - * aware of certain denomination keys from the mint. - */ -#define TALER_SIGNATURE_AUDITOR_MINT_KEYS 1064 - - -/***********************/ -/* Merchant signatures */ -/***********************/ - -/** - * Signature where the merchant confirms a contract (to the customer). - */ -#define TALER_SIGNATURE_MERCHANT_CONTRACT 1101 - -/** - * Signature where the merchant confirms a refund (of a coin). - */ -#define TALER_SIGNATURE_MERCHANT_REFUND 1102 - - -/*********************/ -/* Wallet signatures */ -/*********************/ - -/** - * Signature where the reserve key confirms a withdraw request. - */ -#define TALER_SIGNATURE_WALLET_RESERVE_WITHDRAW 1200 - -/** - * Signature made by the wallet of a user to confirm a deposit of a coin. - */ -#define TALER_SIGNATURE_WALLET_COIN_DEPOSIT 1201 - -/** - * Signature using a coin key confirming the melting of a coin. - */ -#define TALER_SIGNATURE_WALLET_COIN_MELT 1202 - - -/*******************/ -/* Test signatures */ -/*******************/ - -/** - * EdDSA test signature. - */ -#define TALER_SIGNATURE_CLIENT_TEST_EDDSA 1302 - -/** - * EdDSA test signature. - */ -#define TALER_SIGNATURE_MINT_TEST_EDDSA 1303 - - - -GNUNET_NETWORK_STRUCT_BEGIN - -/** - * @brief Format used for to generate the signature on a request to withdraw - * coins from a reserve. - */ -struct TALER_WithdrawRequestPS -{ - - /** - * Purpose must be #TALER_SIGNATURE_WALLET_RESERVE_WITHDRAW. - * Used with an EdDSA signature of a `struct TALER_ReservePublicKeyP`. - */ - struct GNUNET_CRYPTO_EccSignaturePurpose purpose; - - /** - * Reserve public key (which reserve to withdraw from). This is - * the public key which must match the signature. - */ - struct TALER_ReservePublicKeyP reserve_pub; - - /** - * Value of the coin being minted (matching the denomination key) - * plus the transaction fee. We include this in what is being - * signed so that we can verify a reserve's remaining total balance - * without needing to access the respective denomination key - * information each time. - */ - struct TALER_AmountNBO amount_with_fee; - - /** - * Withdrawl fee charged by the mint. This must match the Mint's - * denomination key's withdrawl fee. If the client puts in an - * invalid withdrawl fee (too high or too low) that does not match - * the Mint's denomination key, the withdraw operation is invalid - * and will be rejected by the mint. The @e amount_with_fee minus - * the @e withdraw_fee is must match the value of the generated - * coin. We include this in what is being signed so that we can - * verify a mint's accounting without needing to access the - * respective denomination key information each time. - */ - struct TALER_AmountNBO withdraw_fee; - - /** - * Hash of the denomination public key for the coin that is withdrawn. - */ - struct GNUNET_HashCode h_denomination_pub; - - /** - * Hash of the (blinded) message to be signed by the Mint. - */ - struct GNUNET_HashCode h_coin_envelope; -}; - - -/** - * @brief Format used to generate the signature on a request to deposit - * a coin into the account of a merchant. - */ -struct TALER_DepositRequestPS -{ - /** - * Purpose must be #TALER_SIGNATURE_WALLET_COIN_DEPOSIT. - * Used for an EdDSA signature with the `struct TALER_CoinSpendPublicKeyP`. - */ - struct GNUNET_CRYPTO_EccSignaturePurpose purpose; - - /** - * Hash over the contract for which this deposit is made. - */ - struct GNUNET_HashCode h_contract; - - /** - * Hash over the wiring information of the merchant. - */ - struct GNUNET_HashCode h_wire; - - /** - * Time when this request was generated. Used, for example, to - * assess when (roughly) the income was achieved for tax purposes. - * Note that the Mint will only check that the timestamp is not "too - * far" into the future (i.e. several days). The fact that the - * timestamp falls within the validity period of the coin's - * denomination key is irrelevant for the validity of the deposit - * request, as obviously the customer and merchant could conspire to - * set any timestamp. Also, the Mint must accept very old deposit - * requests, as the merchant might have been unable to transmit the - * deposit request in a timely fashion (so back-dating is not - * prevented). - */ - struct GNUNET_TIME_AbsoluteNBO timestamp; - - /** - * How much time does the merchant have to issue a refund request? - * Zero if refunds are not allowed. After this time, the coin - * cannot be refunded. - */ - struct GNUNET_TIME_AbsoluteNBO refund_deadline; - - /** - * Merchant-generated transaction ID to detect duplicate - * transactions. The merchant must communicate a merchant-unique ID - * to the customer for each transaction. Note that different coins - * that are part of the same transaction can use the same - * transaction ID. The transaction ID is useful for later disputes, - * and the merchant's contract offer (@e h_contract) with the - * customer should include the offer's term and transaction ID - * signed with a key from the merchant. - */ - uint64_t transaction_id GNUNET_PACKED; - - /** - * Amount to be deposited, including deposit fee charged by the - * mint. This is the total amount that the coin's value at the mint - * will be reduced by. - */ - struct TALER_AmountNBO amount_with_fee; - - /** - * Depositing fee charged by the mint. This must match the Mint's - * denomination key's depositing fee. If the client puts in an - * invalid deposit fee (too high or too low) that does not match the - * Mint's denomination key, the deposit operation is invalid and - * will be rejected by the mint. The @e amount_with_fee minus the - * @e deposit_fee is the amount that will be transferred to the - * account identified by @e h_wire. - */ - struct TALER_AmountNBO deposit_fee; - - /** - * The Merchant's public key. Allows the merchant to later refund - * the transaction. All zeros if nobody is allowed to refund the - * transaction later. - */ - struct TALER_MerchantPublicKeyP merchant; - - /** - * The coin's public key. This is the value that must have been - * signed (blindly) by the Mint. The deposit request is to be - * signed by the corresponding private key (using EdDSA). - */ - struct TALER_CoinSpendPublicKeyP coin_pub; - -}; - - -/** - * @brief Format used to generate the signature on a confirmation - * from the mint that a deposit request succeeded. - */ -struct TALER_DepositConfirmationPS -{ - /** - * Purpose must be #TALER_SIGNATURE_MINT_CONFIRM_DEPOSIT. Signed - * by a `struct TALER_MintPublicKeyP` using EdDSA. - */ - struct GNUNET_CRYPTO_EccSignaturePurpose purpose; - - /** - * Hash over the contract for which this deposit is made. - */ - struct GNUNET_HashCode h_contract; - - /** - * Hash over the wiring information of the merchant. - */ - struct GNUNET_HashCode h_wire; - - /** - * Merchant-generated transaction ID to detect duplicate - * transactions. - */ - uint64_t transaction_id GNUNET_PACKED; - - /** - * Time when this confirmation was generated. - */ - struct GNUNET_TIME_AbsoluteNBO timestamp; - - /** - * How much time does the @e merchant have to issue a refund - * request? Zero if refunds are not allowed. After this time, the - * coin cannot be refunded. Note that the wire transfer will not be - * performed by the mint until the refund deadline. This value - * is taken from the original deposit request. - */ - struct GNUNET_TIME_AbsoluteNBO refund_deadline; - - /** - * Amount to be deposited, excluding fee. Calculated from the - * amount with fee and the fee from the deposit request. - */ - struct TALER_AmountNBO amount_without_fee; - - /** - * The coin's public key. This is the value that must have been - * signed (blindly) by the Mint. The deposit request is to be - * signed by the corresponding private key (using EdDSA). - */ - struct TALER_CoinSpendPublicKeyP coin_pub; - - /** - * The Merchant's public key. Allows the merchant to later refund - * the transaction. All zeros if nobody is allowed to refund the - * transaction later. - */ - struct TALER_MerchantPublicKeyP merchant; - -}; - - -/** - * @brief Message signed by a coin to indicate that the coin should be - * melted. - */ -struct TALER_RefreshMeltCoinAffirmationPS -{ - /** - * Purpose is #TALER_SIGNATURE_WALLET_COIN_MELT. - * Used for an EdDSA signature with the `struct TALER_CoinSpendPublicKeyP`. - */ - struct GNUNET_CRYPTO_EccSignaturePurpose purpose; - - /** - * Which melting session should the coin become a part of. - */ - struct GNUNET_HashCode session_hash; - - /** - * How much of the value of the coin should be melted? This amount - * includes the fees, so the final amount contributed to the melt is - * this value minus the fee for melting the coin. We include the - * fee in what is being signed so that we can verify a reserve's - * remaining total balance without needing to access the respective - * denomination key information each time. - */ - struct TALER_AmountNBO amount_with_fee; - - /** - * Melting fee charged by the mint. This must match the Mint's - * denomination key's melting fee. If the client puts in an invalid - * melting fee (too high or too low) that does not match the Mint's - * denomination key, the melting operation is invalid and will be - * rejected by the mint. The @e amount_with_fee minus the @e - * melt_fee is the amount that will be credited to the melting - * session. - */ - struct TALER_AmountNBO melt_fee; - - /** - * The coin's public key. This is the value that must have been - * signed (blindly) by the Mint. The deposit request is to be - * signed by the corresponding private key (using EdDSA). - */ - struct TALER_CoinSpendPublicKeyP coin_pub; -}; - - -/** - * @brief Format of the block signed by the Mint in response to a successful - * "/refresh/melt" request. Hereby the mint affirms that all of the - * coins were successfully melted. This also commits the mint to a - * particular index to not be revealed during the refresh. - */ -struct TALER_RefreshMeltConfirmationPS -{ - /** - * Purpose is #TALER_SIGNATURE_MINT_CONFIRM_MELT. Signed - * by a `struct TALER_MintPublicKeyP` using EdDSA. - */ - struct GNUNET_CRYPTO_EccSignaturePurpose purpose; - - /** - * Hash of the refresh session. - */ - struct GNUNET_HashCode session_hash; - - /** - * Index that the client will not have to reveal, in NBO. - * Must be smaller than #TALER_CNC_KAPPA. - */ - uint16_t noreveal_index GNUNET_PACKED; -}; - - -/** - * @brief Information about a signing key of the mint. Signing keys are used - * to sign mint messages other than coins, i.e. to confirm that a - * deposit was successful or that a refresh was accepted. - */ -struct TALER_MintSigningKeyValidityPS -{ - /** - * Signature over the signing key (by the master key of the mint). - * - * FIXME: should be moved outside of the "PS" struct, this is ugly. - * (and makes this struct different from all of the others) - */ - struct TALER_MasterSignatureP signature; - - /** - * Purpose is #TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY. - */ - struct GNUNET_CRYPTO_EccSignaturePurpose purpose; - - /** - * Master public key of the mint corresponding to @e signature. - * This is the long-term offline master key of the mint. - */ - struct TALER_MasterPublicKeyP master_public_key; - - /** - * When does this signing key begin to be valid? - */ - struct GNUNET_TIME_AbsoluteNBO start; - - /** - * When does this signing key expire? Note: This is currently when - * the Mint will definitively stop using it. Signatures made with - * the key remain valid until @e end. When checking validity periods, - * clients should allow for some overlap between keys and tolerate - * the use of either key during the overlap time (due to the - * possibility of clock skew). - */ - struct GNUNET_TIME_AbsoluteNBO expire; - - /** - * When do signatures with this signing key become invalid? After - * this point, these signatures cannot be used in (legal) disputes - * anymore, as the Mint is then allowed to destroy its side of the - * evidence. @e end is expected to be significantly larger than @e - * expire (by a year or more). - */ - struct GNUNET_TIME_AbsoluteNBO end; - - /** - * The public online signing key that the mint will use - * between @e start and @e expire. - */ - struct TALER_MintPublicKeyP signkey_pub; -}; - - -/** - * @brief Signature made by the mint over the full set of keys, used - * to detect cheating mints that give out different sets to - * different users. - */ -struct TALER_MintKeySetPS -{ - - /** - * Purpose is #TALER_SIGNATURE_MINT_KEY_SET. Signed - * by a `struct TALER_MintPublicKeyP` using EdDSA. - */ - struct GNUNET_CRYPTO_EccSignaturePurpose purpose; - - /** - * Time of the key set issue. - */ - struct GNUNET_TIME_AbsoluteNBO list_issue_date; - - /** - * Hash over the various denomination signing keys returned. - */ - struct GNUNET_HashCode hc; -}; - - -/** - * @brief Information about a denomination key. Denomination keys - * are used to sign coins of a certain value into existence. - */ -struct TALER_DenominationKeyValidityPS -{ - - /** - * Purpose is #TALER_SIGNATURE_MASTER_DENOMINATION_KEY_VALIDITY. - */ - struct GNUNET_CRYPTO_EccSignaturePurpose purpose; - - /** - * The long-term offline master key of the mint that was - * used to create @e signature. - */ - struct TALER_MasterPublicKeyP master; - - /** - * Start time of the validity period for this key. - */ - struct GNUNET_TIME_AbsoluteNBO start; - - /** - * The mint will sign fresh coins between @e start and this time. - * @e expire_withdraw will be somewhat larger than @e start to - * ensure a sufficiently large anonymity set, while also allowing - * the Mint to limit the financial damage in case of a key being - * compromised. Thus, mints with low volume are expected to have a - * longer withdraw period (@e expire_withdraw - @e start) than mints - * with high transaction volume. The period may also differ between - * types of coins. A mint may also have a few denomination keys - * with the same value with overlapping validity periods, to address - * issues such as clock skew. - */ - struct GNUNET_TIME_AbsoluteNBO expire_withdraw; - - /** - * Coins signed with the denomination key must be spent or refreshed - * between @e start and this expiration time. After this time, the - * mint will refuse transactions involving this key as it will - * "drop" the table with double-spending information (shortly after) - * this time. Note that wallets should refresh coins significantly - * before this time to be on the safe side. @e expire_spend must be - * significantly larger than @e expire_withdraw (by months or even - * years). - */ - struct GNUNET_TIME_AbsoluteNBO expire_spend; - - /** - * When do signatures with this denomination key become invalid? - * After this point, these signatures cannot be used in (legal) - * disputes anymore, as the Mint is then allowed to destroy its side - * of the evidence. @e expire_legal is expected to be significantly - * larger than @e expire_spend (by a year or more). - */ - struct GNUNET_TIME_AbsoluteNBO expire_legal; - - /** - * The value of the coins signed with this denomination key. - */ - struct TALER_AmountNBO value; - - /** - * The fee the mint charges when a coin of this type is withdrawn. - * (can be zero). - */ - struct TALER_AmountNBO fee_withdraw; - - /** - * The fee the mint charges when a coin of this type is deposited. - * (can be zero). - */ - struct TALER_AmountNBO fee_deposit; - - /** - * The fee the mint charges when a coin of this type is refreshed. - * (can be zero). - */ - struct TALER_AmountNBO fee_refresh; - - /** - * Hash code of the denomination public key. (Used to avoid having - * the variable-size RSA key in this struct.) - */ - struct GNUNET_HashCode denom_hash; - -}; - - -/** - * @brief Information signed by an auditor affirming - * the master public key and the denomination keys - * of a mint. - */ -struct TALER_MintKeyValidityPS -{ - - /** - * Purpose is #TALER_SIGNATURE_AUDITOR_MINT_KEYS. - */ - struct GNUNET_CRYPTO_EccSignaturePurpose purpose; - - /** - * The long-term offline master key of the mint, affirmed by the - * auditor. - */ - struct TALER_MasterPublicKeyP master; - - /** - * Array of hash(es) of the mint's denomination keys. - * Specifically, this is the hash over the - * `struct TALER_DenominationKeyValidityPS`, not just - * the public key (as the auditor needs to check against - * the correct valuations and fee structure). - */ - /* struct GNUNET_HashCode h_dks; */ - -}; - - -GNUNET_NETWORK_STRUCT_END - -#endif |