"Bitcoin" base58 encoding

Refer to the Base58.h code of the bitcoin source code using a coded function implemented by the OpenSSL Bignum Library as a validation gadget:

Generated:

g++-O base58encode-g base58encode.cc-lcrypto

Source:

#include <stdio.h> #include <stdlib.h> #include <string> #include <openssl/bn.h> #define DOMAIN _check (c) (' 0 ' <= (c) && (c) <= ' 9 ' | | ' A ' <= (c) && (c) <= ' F ' | | ' A ' <= (c) && (c) <= ' F ') const char * base58table= "

123456789ABCDEFGHJKLMNPQRSTUVWXYZABCDEFGHIJKMNOPQRSTUVWXYZ ";
	std::string base58encode (const std::string & hexstring) {std::string result = "";
	Bn_ctx * Bnctx = Bn_ctx_new ();
	Bn_ctx_init (BNCTX);
	Bignum * bn = Bn_new ();
	Bignum * bn0= bn_new ();
	Bignum * Bn58=bn_new ();
	Bignum * dv = bn_new ();
	Bignum * rem= bn_new (); 
	Bn_init (BN);
	Bn_init (BN0);
	Bn_init (bn58);
	Bn_init (DV);

	Bn_init (REM);
	Bn_hex2bn (&bn, Hexstring.c_str ());
	printf ("bn:%s\n", Bn_bn2dec (BN));

	Bn_hex2bn (&bn58, "3a");//58 bn_hex2bn (&bn0, "0");
		while (bn_cmp (BN, bn0) >0) {Bn_div (DV, Rem, BN, bn58, Bnctx);
		Bn_copy (BN, DV);
		printf ("DV:%s\n", Bn_bn2dec (DV));
		printf ("rem:%s\n", Bn_bn2dec (REM)); Char Base58char = Base58table[bn_Get_word (REM)];
	result + = Base58char;
	} std::string::iterator Pbegin = Result.begin ();
	Std::string::iterator pend = Result.end ();
		while (Pbegin < pend) {char c = *pbegin;
		* (pbegin++) = * (--pend);
	*pend = C;
} return result;
	} int main (int argc, char * argv []) {std::string hexstring = "";
	FILE * fin = stdin;
		while (!feof (Fin)) {char c = fgetc (Fin);
	if (Domain_check (c)) hexstring +=c;
	} fprintf (stdout, "%s", Base58encode (hexstring). C_STR ());
return 0; }

Test:

Echo-n

00010966776006953d5567439e5e39f86a0d273beed61967f6

|./base58encode

Printed:6UWLL9RISC3QFPQBUVKOFHMBQ7WMTJVM

Because there are 2 leading 0 ahead, the address should be 16UWLL9RISC3QFPQBUVKOFHMBQ7WMTJVM

Reference address generation inside the code: Add the processing of the leading 0, generate the final Bitcoin address

BASE58 definition of leading version byte:

Use

Decimal version	Leading symbol		Example
0	1	Bitcoin PubKey Hash	17vznx1sn5ntka8uqfxwqbfefc3iqryhem
5	3	Bitcoin Script Hash	3ektnhqd7riae6uzmj2zift9ygrrksgzqx
111	M or N	Bitcoin testnet PubKey Hash	Mipcbbfg9gmich81kj8tqqdgozub1zjrfn
128	5	Bitcoin Private key (for uncompressed PubKey)	5hwgr3u458glafkbgxtsshspqjnyogrszgqspwlfhlnyskdpyya
128	K or L	Bitcoin Private key (for compressed pubkey)	L1aw4aubdfb7yfras2s1mn3bqg9nwysy8nkolmjebsld5bwv3enz
196	2	Testnet Script Hash	2mzqwssnbhwhqsaqttvq6v47xtaisrja1vc
239	9	Testnet Private key (for uncompressed PubKey)	92pg46ruhgtt7romnv7igw6w1gbgdeezqdbjczshkcsynzyyncc
239	C	Testnet Private key (for compressed pubkey)	Cnjfgo1drifnpcbdbx8brjrpxchbwxwxcvnh5soskdcf6jxxwhmm

The definition of a leading byte that differs from the public key address:

    Compute the length of a pubkey with a given first byte.
    unsigned int static getlen (unsigned char chheader) {
        if (Chheader = = 2 | | chheader = 3)//compression method
            return;
        if (Chheader = = 4 | | chheader = = 6 | | chheader = = 7)//non-compression method
            return;
        return 0;
    }

Discuss:

1) about the address leading 0, that is, the base58 1, this can be achieved, hexstring every 2 characters is a byte, followed by a byte array, to see the beginning of the 0 subscript, how many bytes are 0x00, the front of how many 1 put to the front, The version number of the general address is 0x00, so you'll almost see a bitcoin address that starts at 1.

Reference:

Https://en.bitcoin.it/wiki/Technical_background_of_Bitcoin_addresses

Https://en.bitcoin.it/wiki/List_of_address_prefixes

Https://en.bitcoin.it/wiki/Base58Check_encoding