fc::em::signature_shim Struct Reference

#include <elliptic_em.hpp>

Inheritance diagram for fc::em::signature_shim:

Collaboration diagram for fc::em::signature_shim:

Public Types
using	public_key_type = public_key_shim
Public Types inherited from fc::crypto::shim< compact_signature >
using	data_type

Public Member Functions
public_key_type	recover (const sha256 &digest, bool check_canonical) const
Public Member Functions inherited from fc::crypto::shim< compact_signature >
	shim ()
	shim (data_type &&data)
	shim (const data_type &data)
const data_type &	serialize () const

Additional Inherited Members
Public Attributes inherited from fc::crypto::shim< compact_signature >
data_type	_data

Detailed Description

Definition at line 161 of file elliptic_em.hpp.

Member Typedef Documentation

public_key_type

using fc::em::signature_shim::public_key_type = public_key_shim

Definition at line 162 of file elliptic_em.hpp.

Member Function Documentation

recover()

public_key_type fc::em::signature_shim::recover ( const sha256 & digest, bool check_canonical ) const

inline

Definition at line 165 of file elliptic_em.hpp.

                                                                                   {
            // "x19Ethereum Signed Message:\n" is the header used by the `eth_sign` RPC call. We have converted the string to its hex value to save a step.
            // std::string erc155_message_prefix = "19457468657265756d205369676e6564204d6573736167653a0a3332";
            uint8_t eth_prefix[28] = {
               25,  69, 116, 104, 101, 114, 101,
               117, 109,  32,  83, 105, 103, 110,
               101, 100,  32,  77, 101, 115, 115,
               97, 103, 101,  58,  10,  51,  50
            };
            // Hash (keccak256) the msg string
 
            // unsigned char msg_digest_result = digest.data();
            unsigned char eth_prefixed_msg_raw[28 + 32];
            std::copy(std::begin(eth_prefix), std::end(eth_prefix), std::begin(eth_prefixed_msg_raw));
            std::copy((unsigned char*) digest.data(), (unsigned char*) digest.data() + 32, std::begin(eth_prefixed_msg_raw) + 28);
 
            SHA3_CTX msg_ctx;
            keccak_init(&msg_ctx);
            keccak_update(&msg_ctx, eth_prefixed_msg_raw, 60);
            
            // Hash the newly created raw message.
            unsigned char msg_digest_result[32];
            keccak_final(&msg_ctx, msg_digest_result);
 
            // sha256 msg_digest 
            return public_key_type(public_key(_data, msg_digest_result, false).serialize());
         }

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The documentation for this struct was generated from the following file:

• libraries/fc/include/fc/crypto/elliptic_em.hpp