release, all: integrate the release service into geth

1 files changed, 249 insertions, 0 deletions

diff --git a/release/contract.sol b/release/contract.sol
new file mode 100644
index 000000000..fedf646c0
--- /dev/null
+++ b/release/contract.sol
@@ -0,0 +1,249 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library 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 Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// ReleaseOracle is an Ethereum contract to store the current and previous
+// versions of the go-ethereum implementation. Its goal is to allow Geth to
+// check for new releases automatically without the need to consult a central
+// repository.
+//
+// The contract takes a vote based approach on both assigning authorised signers
+// as well as signing off on new Geth releases.
+//
+// Note, when a signer is demoted, the currently pending release is auto-nuked.
+// The reason is to prevent suprises where a demotion actually tilts the votes
+// in favor of one voter party and pushing out a new release as a consequence of
+// a simple demotion.
+contract ReleaseOracle {
+  // Votes is an internal data structure to count votes on a specific proposal
+  struct Votes {
+    address[] pass; // List of signers voting to pass a proposal
+    address[] fail; // List of signers voting to fail a proposal
+  }
+
+  // Version is the version details of a particular Geth release
+  struct Version {
+    uint32  major;  // Major version component of the release
+    uint32  minor;  // Minor version component of the release
+    uint32  patch;  // Patch version component of the release
+    bytes20 commit; // Git SHA1 commit hash of the release
+
+    uint64  time;  // Timestamp of the release approval
+    Votes   votes; // Votes that passed this release
+  }
+
+  // Oracle authorization details
+  mapping(address => bool) authorised; // Set of accounts allowed to vote on updating the contract
+  address[]                voters;     // List of addresses currently accepted as signers
+
+  // Various proposals being voted on
+  mapping(address => Votes) authProps; // Currently running user authorization proposals
+  address[]                 authPend;  // List of addresses being voted on (map indexes)
+
+  Version   verProp;  // Currently proposed release being voted on
+  Version[] releases; // All the positively voted releases
+
+  // isSigner is a modifier to authorize contract transactions.
+  modifier isSigner() {
+    if (authorised[msg.sender]) {
+      _
+    }
+  }
+
+  // Constructor to assign the initial set of signers.
+  function ReleaseOracle(address[] signers) {
+    // If no signers were specified, assign the creator as the sole signer
+    if (signers.length == 0) {
+      authorised[msg.sender] = true;
+      voters.push(msg.sender);
+      return;
+    }
+    // Otherwise assign the individual signers one by one
+    for (uint i = 0; i < signers.length; i++) {
+      authorised[signers[i]] = true;
+      voters.push(signers[i]);
+    }
+  }
+
+  // signers is an accessor method to retrieve all te signers (public accessor
+  // generates an indexed one, not a retreive-all version).
+  function signers() constant returns(address[]) {
+    return voters;
+  }
+
+  // authProposals retrieves the list of addresses that authorization proposals
+  // are currently being voted on.
+  function authProposals() constant returns(address[]) {
+    return authPend;
+  }
+
+  // authVotes retrieves the current authorization votes for a particular user
+  // to promote him into the list of signers, or demote him from there.
+  function authVotes(address user) constant returns(address[] promote, address[] demote) {
+    return (authProps[user].pass, authProps[user].fail);
+  }
+
+  // currentVersion retrieves the semantic version, commit hash and release time
+  // of the currently votec active release.
+  function currentVersion() constant returns (uint32 major, uint32 minor, uint32 patch, bytes20 commit, uint time) {
+    if (releases.length == 0) {
+      return (0, 0, 0, 0, 0);
+    }
+    var release = releases[releases.length - 1];
+
+    return (release.major, release.minor, release.patch, release.commit, release.time);
+  }
+
+  // proposedVersion retrieves the semantic version, commit hash and the current
+  // votes for the next proposed release.
+  function proposedVersion() constant returns (uint32 major, uint32 minor, uint32 patch, bytes20 commit, address[] pass, address[] fail) {
+    return (verProp.major, verProp.minor, verProp.patch, verProp.commit, verProp.votes.pass, verProp.votes.fail);
+  }
+
+  // promote pitches in on a voting campaign to promote a new user to a signer
+  // position.
+  function promote(address user) {
+    updateSigner(user, true);
+  }
+
+  // demote pitches in on a voting campaign to demote an authorised user from
+  // its signer position.
+  function demote(address user) {
+    updateSigner(user, false);
+  }
+
+  // release votes for a particular version to be included as the next release.
+  function release(uint32 major, uint32 minor, uint32 patch, bytes20 commit) {
+    updateRelease(major, minor, patch, commit, true);
+  }
+
+  // nuke votes for the currently proposed version to not be included as the next
+  // release. Nuking doesn't require a specific version number for simplicity.
+  function nuke() {
+    updateRelease(0, 0, 0, 0, false);
+  }
+
+  // updateSigner marks a vote for changing the status of an Ethereum user, either
+  // for or against the user being an authorised signer.
+  function updateSigner(address user, bool authorize) internal isSigner {
+    // Gather the current votes and ensure we don't double vote
+    Votes votes = authProps[user];
+    for (uint i = 0; i < votes.pass.length; i++) {
+      if (votes.pass[i] == msg.sender) {
+        return;
+      }
+    }
+    for (i = 0; i < votes.fail.length; i++) {
+      if (votes.fail[i] == msg.sender) {
+        return;
+      }
+    }
+    // If no authorization proposal is open, add the user to the index for later lookups
+    if (votes.pass.length == 0 && votes.fail.length == 0) {
+      authPend.push(user);
+    }
+    // Cast the vote and return if the proposal cannot be resolved yet
+    if (authorize) {
+      votes.pass.push(msg.sender);
+      if (votes.pass.length <= voters.length / 2) {
+        return;
+      }
+    } else {
+      votes.fail.push(msg.sender);
+      if (votes.fail.length <= voters.length / 2) {
+        return;
+      }
+    }
+    // Proposal resolved in our favor, execute whatever we voted on
+    if (authorize && !authorised[user]) {
+      authorised[user] = true;
+      voters.push(user);
+    } else if (!authorize && authorised[user]) {
+      authorised[user] = false;
+
+      for (i = 0; i < voters.length; i++) {
+        if (voters[i] == user) {
+          voters[i] = voters[voters.length - 1];
+          voters.length--;
+
+          delete verProp; // Nuke any version proposal (no suprise releases!)
+          break;
+        }
+      }
+    }
+    // Finally delete the resolved proposal, index and garbage collect
+    delete authProps[user];
+
+    for (i = 0; i < authPend.length; i++) {
+      if (authPend[i] == user) {
+        authPend[i] = authPend[authPend.length - 1];
+        authPend.length--;
+        break;
+      }
+    }
+  }
+
+  // updateRelease votes for a particular version to be included as the next release,
+  // or for the currently proposed release to be nuked out.
+  function updateRelease(uint32 major, uint32 minor, uint32 patch, bytes20 commit, bool release) internal isSigner {
+    // Skip nuke votes if no proposal is pending
+    if (!release && verProp.votes.pass.length == 0) {
+      return;
+    }
+    // Mark a new release if no proposal is pending
+    if (verProp.votes.pass.length == 0) {
+      verProp.major  = major;
+      verProp.minor  = minor;
+      verProp.patch  = patch;
+      verProp.commit = commit;
+    }
+    // Make sure positive votes match the current proposal
+    if (release && (verProp.major != major || verProp.minor != minor || verProp.patch != patch || verProp.commit != commit)) {
+      return;
+    }
+    // Gather the current votes and ensure we don't double vote
+    Votes votes = verProp.votes;
+    for (uint i = 0; i < votes.pass.length; i++) {
+      if (votes.pass[i] == msg.sender) {
+        return;
+      }
+    }
+    for (i = 0; i < votes.fail.length; i++) {
+      if (votes.fail[i] == msg.sender) {
+        return;
+      }
+    }
+    // Cast the vote and return if the proposal cannot be resolved yet
+    if (release) {
+      votes.pass.push(msg.sender);
+      if (votes.pass.length <= voters.length / 2) {
+        return;
+      }
+    } else {
+      votes.fail.push(msg.sender);
+      if (votes.fail.length <= voters.length / 2) {
+        return;
+      }
+    }
+    // Proposal resolved in our favor, execute whatever we voted on
+    if (release) {
+      verProp.time = uint64(now);
+      releases.push(verProp);
+      delete verProp;
+    } else {
+      delete verProp;
+    }
+  }
+}