Coverage Report

Created: 2025-11-16 06:56

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/src/botan/build/include/public/botan/pk_keys.h
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/*
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* PK Key Types
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* (C) 1999-2007,2018 Jack Lloyd
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*
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* Botan is released under the Simplified BSD License (see license.txt)
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*/
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#ifndef BOTAN_PK_KEYS_H_
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#define BOTAN_PK_KEYS_H_
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#include <botan/asn1_obj.h>
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#include <botan/pk_ops_fwd.h>
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#include <botan/secmem.h>
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#include <memory>
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#include <optional>
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#include <span>
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#include <string>
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#include <string_view>
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namespace Botan {
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class BigInt;
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class RandomNumberGenerator;
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/**
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* Enumeration specifying the signature format.
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*
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* This is mostly used for requesting DER encoding of ECDSA signatures;
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* most other algorithms only support "standard".
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*/
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enum class Signature_Format : uint8_t {
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   Standard = 0,
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   DerSequence = 1,
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   IEEE_1363 BOTAN_DEPRECATED("Use Standard") = Standard,
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   DER_SEQUENCE BOTAN_DEPRECATED("Use DerSequence") = DerSequence,
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};
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/**
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* Enumeration of possible operations a public key could be used for.
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*
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* It is possible to query if a key supports a particular operation
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* type using Asymmetric_Key::supports_operation()
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*/
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enum class PublicKeyOperation : uint8_t {
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   Encryption,
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   Signature,
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   KeyEncapsulation,
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   KeyAgreement,
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};
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class Private_Key;
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/**
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* An interface for objects that are keys in public key algorithms
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*
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* This is derived for both public and private keys
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*/
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class BOTAN_PUBLIC_API(3, 0) Asymmetric_Key /* NOLINT(*special-member-functions) */ {
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   public:
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      virtual ~Asymmetric_Key() = default;
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      /**
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      * Get the name of the underlying public key scheme.
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      * @return name of the public key scheme
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      */
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      virtual std::string algo_name() const = 0;
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      /**
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      * Return the estimated strength of the underlying key against
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      * the best currently known attack. Note that this ignores anything
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      * but pure attacks against the key itself and do not take into
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      * account padding schemes, usage mistakes, etc which might reduce
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      * the strength. However it does suffice to provide an upper bound.
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      *
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      * @return estimated strength in bits
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      */
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      virtual size_t estimated_strength() const = 0;
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      /**
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      * Get the OID of the underlying public key scheme.
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      * @return OID of the public key scheme
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      */
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      virtual OID object_identifier() const;
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      /**
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      * Access an algorithm specific field
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      *
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      * If the field is not known for this algorithm, an Invalid_Argument is
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      * thrown. The interpretation of the result requires knowledge of which
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      * algorithm is involved. For instance for RSA "p" represents one of the
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      * secret primes, while for DSA "p" is the public prime.
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      *
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      * Some algorithms may not implement this method at all.
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      *
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      * This is primarily used to implement the FFI botan_pubkey_get_field
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      * and botan_privkey_get_field functions.
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      *
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      * TODO(Botan4) Change this to return by value
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      */
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      virtual const BigInt& get_int_field(std::string_view field) const;
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      /**
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      * Return true if this key could be used for the specified type
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      * of operation.
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      */
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      virtual bool supports_operation(PublicKeyOperation op) const = 0;
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      /**
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       * Generate another (cryptographically independent) key pair using the
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       * same algorithm parameters as this key. This is most useful for algorithms
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       * that support PublicKeyOperation::KeyAgreement to generate a fitting ephemeral
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       * key pair. For other key types it might throw Not_Implemented.
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       */
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      virtual std::unique_ptr<Private_Key> generate_another(RandomNumberGenerator& rng) const = 0;
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      /*
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      * Test the key values for consistency.
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      * @param rng rng to use
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      * @param strong whether to perform strong and lengthy version of the test
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      * @return true if the test is passed
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      */
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      virtual bool check_key(RandomNumberGenerator& rng, bool strong) const = 0;
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      // Declarations for internal library functions not covered by SemVer follow
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      /**
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      * Certain signatures schemes such as ECDSA have more than
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      * one element, and certain unfortunate protocols decided the
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      * thing to do was not concatenate them as normally done, but
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      * instead DER encode each of the elements as independent values.
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      *
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      * If this returns a value x then the signature is checked to
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      * be exactly 2*x bytes and split in half for DER encoding.
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      */
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      virtual std::optional<size_t> _signature_element_size_for_DER_encoding() const { return {}; }
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      /*
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      * Return the format normally used by this algorithm for X.509 signatures
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      */
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      virtual Signature_Format _default_x509_signature_format() const;
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};
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/*
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* Public Key Base Class.
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*/
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class BOTAN_PUBLIC_API(2, 0) Public_Key : public virtual Asymmetric_Key {
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   public:
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      /**
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      * Return an integer value best approximating the length of the
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      * primary security parameter. For example for RSA this will be
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      * the size of the modulus, for ECDSA the size of the ECC group,
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      * and for McEliece the size of the code will be returned.
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      */
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      virtual size_t key_length() const = 0;
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      /**
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      * Deprecated version of object_identifier
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      */
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      BOTAN_DEPRECATED("Use object_identifier") OID get_oid() const { return this->object_identifier(); }
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      /**
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      * @return X.509 AlgorithmIdentifier for this key
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      */
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      virtual AlgorithmIdentifier algorithm_identifier() const = 0;
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      /**
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      * @return binary public key bits, with no additional encoding
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      *
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      * For key agreements this is an alias for PK_Key_Agreement_Key::public_value.
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      *
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      * Note: some algorithms (for example RSA) do not have an obvious encoding
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      * for this value due to having many different values, and thus throw
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      * Not_Implemented when invoking this method.
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      */
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      virtual std::vector<uint8_t> raw_public_key_bits() const = 0;
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      /**
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      * @return BER encoded public key bits
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      */
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      virtual std::vector<uint8_t> public_key_bits() const = 0;
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      /**
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      * @return X.509 subject key encoding for this key object
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      */
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      std::vector<uint8_t> subject_public_key() const;
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      /**
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       * @return Hash of the subject public key
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       */
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      std::string fingerprint_public(std::string_view alg = "SHA-256") const;
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      // Declarations for internal library functions not covered by SemVer follow
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      /**
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      * Returns more than 1 if the output of this algorithm
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      * (ciphertext, signature) should be treated as more than one
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      * value. This is used for algorithms like DSA and ECDSA, where
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      * the (r,s) output pair can be encoded as either a plain binary
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      * list or a TLV tagged DER encoding depending on the protocol.
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      *
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      * This function is public but applications should have few
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      * reasons to ever call this.
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      *
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      * @return number of message parts
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      */
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      BOTAN_DEPRECATED("Deprecated no replacement") size_t message_parts() const {
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         return _signature_element_size_for_DER_encoding() ? 2 : 1;
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      }
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      /**
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      * Returns how large each of the message parts refered to
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      * by message_parts() is
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      *
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      * This function is public but applications should have few
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      * reasons to ever call this.
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      *
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      * @return size of the message parts in bits
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      */
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      BOTAN_DEPRECATED("Deprecated no replacement") size_t message_part_size() const {
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         return _signature_element_size_for_DER_encoding().value_or(0);
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      }
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      /*
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      * Return the format normally used by this algorithm for X.509 signatures
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      */
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      BOTAN_DEPRECATED("Deprecated no replacement")
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      Signature_Format default_x509_signature_format() const /* NOLINT(bugprone-virtual-near-miss) */ {
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         return _default_x509_signature_format();
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      }
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      /**
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      * This is an internal library function exposed on key types.
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      * In almost all cases applications should use wrappers in pubkey.h
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      *
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      * Return an encryption operation for this key/params or throw
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      *
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      * @param rng a random number generator. The PK_Op may maintain a
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      * reference to the RNG and use it many times. The rng must outlive
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      * any operations which reference it.
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      * @param params additional parameters
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      * @param provider the provider to use
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      */
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      virtual std::unique_ptr<PK_Ops::Encryption> create_encryption_op(RandomNumberGenerator& rng,
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                                                                       std::string_view params,
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                                                                       std::string_view provider) const;
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      /**
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      * This is an internal library function exposed on key types.
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      * In almost all cases applications should use wrappers in pubkey.h
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      *
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      * Return a KEM encryption operation for this key/params or throw
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      *
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      * @param params additional parameters
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      * @param provider the provider to use
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      */
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      virtual std::unique_ptr<PK_Ops::KEM_Encryption> create_kem_encryption_op(std::string_view params,
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                                                                               std::string_view provider) const;
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      /**
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      * This is an internal library function exposed on key types.
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      * In all cases applications should use wrappers in pubkey.h
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      *
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      * Return a verification operation for this key/params or throw
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      * @param params additional parameters
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      * @param provider the provider to use
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      */
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      virtual std::unique_ptr<PK_Ops::Verification> create_verification_op(std::string_view params,
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                                                                           std::string_view provider) const;
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      /**
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      * This is an internal library function exposed on key types.
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      * In all cases applications should use wrappers in pubkey.h
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      *
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      * Return a verification operation for this combination of key and
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      * signature algorithm or throw.
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      *
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      * @param signature_algorithm is the X.509 algorithm identifier encoding the padding
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      * scheme and hash hash function used in the signature if applicable.
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      *
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      * @param provider the provider to use
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      */
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      virtual std::unique_ptr<PK_Ops::Verification> create_x509_verification_op(
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         const AlgorithmIdentifier& signature_algorithm, std::string_view provider) const;
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};
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/**
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* Private Key Base Class
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*/
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class BOTAN_PUBLIC_API(2, 0) Private_Key : public virtual Public_Key {
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   public:
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      /**
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      * @return BER encoded private key bits
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      */
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      virtual secure_vector<uint8_t> private_key_bits() const = 0;
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      /**
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      * @return binary private key bits, with no additional encoding
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      *
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      * Note: some algorithms (for example RSA) do not have an obvious encoding
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      * for this value due to having many different values, and thus not implement
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      * this function. The default implementation throws Not_Implemented
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      */
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      virtual secure_vector<uint8_t> raw_private_key_bits() const;
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      /**
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      * Allocate a new object for the public key associated with this
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      * private key.
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      *
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      * @return public key
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      */
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      virtual std::unique_ptr<Public_Key> public_key() const = 0;
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      /**
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      * @return PKCS #8 private key encoding for this key object
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      */
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      secure_vector<uint8_t> private_key_info() const;
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      /**
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      * @return PKCS #8 AlgorithmIdentifier for this key
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      * Might be different from the X.509 identifier, but normally is not
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      */
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      virtual AlgorithmIdentifier pkcs8_algorithm_identifier() const { return algorithm_identifier(); }
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      /**
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      * Indicates if this key is stateful, ie that performing a private
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      * key operation requires updating the key storage.
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      */
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      virtual bool stateful_operation() const { return false; }
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      /**
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       * @brief Retrieves the number of remaining operations if this is a stateful private key.
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       *
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       * @returns the number of remaining operations or std::nullopt if not applicable.
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       */
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      virtual std::optional<uint64_t> remaining_operations() const { return std::nullopt; }
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      // Declarations for internal library functions not covered by SemVer follow
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      /**
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       * @return Hash of the PKCS #8 encoding for this key object
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       */
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      std::string fingerprint_private(std::string_view alg) const;
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      /**
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      * This is an internal library function exposed on key types.
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      * In all cases applications should use wrappers in pubkey.h
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      *
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      * Return an decryption operation for this key/params or throw
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      *
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      * @param rng a random number generator. The PK_Op may maintain a
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      * reference to the RNG and use it many times. The rng must outlive
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      * any operations which reference it.
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      * @param params additional parameters
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      * @param provider the provider to use
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      *
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      */
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      virtual std::unique_ptr<PK_Ops::Decryption> create_decryption_op(RandomNumberGenerator& rng,
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                                                                       std::string_view params,
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                                                                       std::string_view provider) const;
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      /**
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      * This is an internal library function exposed on key types.
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      * In all cases applications should use wrappers in pubkey.h
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      *
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      * Return a KEM decryption operation for this key/params or throw
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      *
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      * @param rng a random number generator. The PK_Op may maintain a
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      * reference to the RNG and use it many times. The rng must outlive
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      * any operations which reference it.
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      * @param params additional parameters
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      * @param provider the provider to use
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      */
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      virtual std::unique_ptr<PK_Ops::KEM_Decryption> create_kem_decryption_op(RandomNumberGenerator& rng,
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                                                                               std::string_view params,
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                                                                               std::string_view provider) const;
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      /**
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      * This is an internal library function exposed on key types.
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      * In all cases applications should use wrappers in pubkey.h
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      *
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      * Return a signature operation for this key/params or throw
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      *
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      * @param rng a random number generator. The PK_Op may maintain a
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      * reference to the RNG and use it many times. The rng must outlive
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      * any operations which reference it.
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      * @param params additional parameters
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      * @param provider the provider to use
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      */
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      virtual std::unique_ptr<PK_Ops::Signature> create_signature_op(RandomNumberGenerator& rng,
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                                                                     std::string_view params,
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                                                                     std::string_view provider) const;
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      /**
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      * This is an internal library function exposed on key types.
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      * In all cases applications should use wrappers in pubkey.h
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      *
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      * Return a key agreement operation for this key/params or throw
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      *
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      * @param rng a random number generator. The PK_Op may maintain a
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      * reference to the RNG and use it many times. The rng must outlive
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      * any operations which reference it.
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      * @param params additional parameters
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      * @param provider the provider to use
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      */
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      virtual std::unique_ptr<PK_Ops::Key_Agreement> create_key_agreement_op(RandomNumberGenerator& rng,
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                                                                             std::string_view params,
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                                                                             std::string_view provider) const;
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};
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/**
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* PK Secret Value Derivation Key
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*/
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class BOTAN_PUBLIC_API(2, 0) PK_Key_Agreement_Key : public virtual Private_Key {
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   public:
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      /*
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      * @return public component of this key
419
      */
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      virtual std::vector<uint8_t> public_value() const = 0;
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};
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std::string BOTAN_PUBLIC_API(2, 4) create_hex_fingerprint(const uint8_t bits[], size_t len, std::string_view hash_name);
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0
inline std::string create_hex_fingerprint(std::span<const uint8_t> vec, std::string_view hash_name) {
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0
   return create_hex_fingerprint(vec.data(), vec.size(), hash_name);
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0
}
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}  // namespace Botan
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#endif