Bitcoin Forum
November 23, 2017, 01:34:08 PM *
News: Latest stable version of Bitcoin Core: 0.15.1  [Torrent].
 
   Home   Help Search Donate Login Register  
Pages: [1]
  Print  
Author Topic: Obtaining the public key from the public address  (Read 585 times)
Shevek
Sr. Member
****
Offline Offline

Activity: 252



View Profile
April 03, 2013, 10:55:46 AM
 #1

I'm sure it is a dumb question, answered a lot of times. But it is difficult to search such topic over this forums.

So: the public address (that is propagated) is a hash of the public key. The public key is needed for checking transactions. But reversing the public address to obtain the public key is impossible, because of the nature of hash functions.

What is the solution!?

TIA.

Proposals for improving bitcoin are like asses: everybody has one
1SheveKuPHpzpLqSvPSavik9wnC51voBa
Join ICO Now A blockchain platform for effective freelancing
Advertised sites are not endorsed by the Bitcoin Forum. They may be unsafe, untrustworthy, or illegal in your jurisdiction. Advertise here.
1511444048
Hero Member
*
Offline Offline

Posts: 1511444048

View Profile Personal Message (Offline)

Ignore
1511444048
Reply with quote  #2

1511444048
Report to moderator
1511444048
Hero Member
*
Offline Offline

Posts: 1511444048

View Profile Personal Message (Offline)

Ignore
1511444048
Reply with quote  #2

1511444048
Report to moderator
1511444048
Hero Member
*
Offline Offline

Posts: 1511444048

View Profile Personal Message (Offline)

Ignore
1511444048
Reply with quote  #2

1511444048
Report to moderator
dust
Hero Member
*****
Offline Offline

Activity: 840



View Profile WWW
April 03, 2013, 11:00:19 AM
 #2

The public key corresponding to an address is revealed when coins are first spent from that address.

Cryptocoin Mining Info | OTC | PGP | Twitter | freenode: dust-otc | BTC: 1F6fV4U2xnpAuKtmQD6BWpK3EuRosKzF8U
fpgaminer
Hero Member
*****
Offline Offline

Activity: 560



View Profile WWW
April 03, 2013, 11:01:46 AM
 #3

When bitcoins are sent to an address, they are sent using the standard pay-to-hash output script:

Code:
OP_DUP OP_HASH160 <pubKeyHash> OP_EQUALVERIFY OP_CHECKSIG

For the receiver to spend this output, they need to supply a scriptSig of:

Code:
<sig> <pubKey>

And thus you see that the public key is revealed when the receiver spends the bitcoins.  Until such a time, the public key may remain unknown.

Shevek
Sr. Member
****
Offline Offline

Activity: 252



View Profile
April 03, 2013, 01:55:09 PM
 #4

Yeeeaap!

Thanks!

Proposals for improving bitcoin are like asses: everybody has one
1SheveKuPHpzpLqSvPSavik9wnC51voBa
Pages: [1]
  Print  
 
Jump to:  

Sponsored by , a Bitcoin-accepting VPN.
Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!