import com.subgraph.orchid.directory.TrustedAuthorities; //导入依赖的package包/类
public synchronized SignatureStatus verifySignatures() {
	boolean firstCall = isFirstCallToVerifySignatures;
	isFirstCallToVerifySignatures = false;
	requiredCertificates.clear();
	int verifiedCount = 0;
	int certsNeededCount = 0;
	final int v3Count = TrustedAuthorities.getInstance().getV3AuthorityServerCount();
	final int required = (v3Count / 2) + 1;
	
	for(VoteAuthorityEntry entry: voteAuthorityEntries.values()) {
		switch(verifySingleAuthority(entry)) {
		case STATUS_FAILED:
			break;
		case STATUS_NEED_CERTS:
			certsNeededCount += 1;
			break;
		case STATUS_VERIFIED:
			verifiedCount += 1;
			break;
		}
	}
	
	if(verifiedCount >= required) {
		return SignatureStatus.STATUS_VERIFIED;
	} else if(verifiedCount + certsNeededCount >= required) {
		if(firstCall) {
			logger.info("Certificates need to be retrieved to verify consensus");
		}
		return SignatureStatus.STATUS_NEED_CERTS;
	} else {
		return SignatureStatus.STATUS_FAILED;
	}
}
 

import com.subgraph.orchid.directory.TrustedAuthorities; //导入依赖的package包/类
private SignatureStatus verifySingleAuthority(VoteAuthorityEntry authority) {
	
	boolean certsNeeded = false;
	boolean validSignature = false;
	
	for(DirectorySignature s: authority.getSignatures()) {
		DirectoryServer trusted = TrustedAuthorities.getInstance().getAuthorityServerByIdentity(s.getIdentityDigest());
		if(trusted == null) {
			logger.warning("Consensus signed by unrecognized directory authority: "+ s.getIdentityDigest());
			return SignatureStatus.STATUS_FAILED;
		} else {
			switch(verifySignatureForTrustedAuthority(trusted, s)) {
			case STATUS_NEED_CERTS:
				certsNeeded = true;
				break;
			case STATUS_VERIFIED:
				validSignature = true;
				break;
			default:
				break;
			}
		}
	}
	
	if(validSignature) {
		return SignatureStatus.STATUS_VERIFIED;
	} else if(certsNeeded) {
		return SignatureStatus.STATUS_NEED_CERTS;
	} else {
		return SignatureStatus.STATUS_FAILED;
	}
}