canonicalize: require primary key binding certificates for signing subkeys

This commit is contained in:
Vincent Breitmoser 2014-06-12 23:10:44 +02:00
parent 79131be5f0
commit 073433fa74
3 changed files with 49 additions and 5 deletions

View File

@ -3,6 +3,8 @@ package org.sufficientlysecure.keychain.pgp;
import org.spongycastle.bcpg.ArmoredOutputStream; import org.spongycastle.bcpg.ArmoredOutputStream;
import org.spongycastle.bcpg.S2K; import org.spongycastle.bcpg.S2K;
import org.spongycastle.bcpg.SignatureSubpacketTags; import org.spongycastle.bcpg.SignatureSubpacketTags;
import org.spongycastle.bcpg.sig.KeyFlags;
import org.spongycastle.openpgp.PGPKeyFlags;
import org.spongycastle.openpgp.PGPKeyRing; import org.spongycastle.openpgp.PGPKeyRing;
import org.spongycastle.openpgp.PGPObjectFactory; import org.spongycastle.openpgp.PGPObjectFactory;
import org.spongycastle.openpgp.PGPPublicKey; import org.spongycastle.openpgp.PGPPublicKey;
@ -10,6 +12,7 @@ import org.spongycastle.openpgp.PGPPublicKeyRing;
import org.spongycastle.openpgp.PGPSecretKey; import org.spongycastle.openpgp.PGPSecretKey;
import org.spongycastle.openpgp.PGPSecretKeyRing; import org.spongycastle.openpgp.PGPSecretKeyRing;
import org.spongycastle.openpgp.PGPSignature; import org.spongycastle.openpgp.PGPSignature;
import org.spongycastle.openpgp.PGPSignatureList;
import org.spongycastle.openpgp.PGPUtil; import org.spongycastle.openpgp.PGPUtil;
import org.sufficientlysecure.keychain.Constants; import org.sufficientlysecure.keychain.Constants;
import org.sufficientlysecure.keychain.pgp.exception.PgpGeneralException; import org.sufficientlysecure.keychain.pgp.exception.PgpGeneralException;
@ -298,7 +301,6 @@ public class UncachedKeyRing {
WrappedSignature cert = new WrappedSignature(zert); WrappedSignature cert = new WrappedSignature(zert);
long certId = cert.getKeyId(); long certId = cert.getKeyId();
int type = zert.getSignatureType(); int type = zert.getSignatureType();
if (type != PGPSignature.DEFAULT_CERTIFICATION if (type != PGPSignature.DEFAULT_CERTIFICATION
&& type != PGPSignature.NO_CERTIFICATION && type != PGPSignature.NO_CERTIFICATION
@ -435,9 +437,12 @@ public class UncachedKeyRing {
// certificate. // certificate.
PGPPublicKey modified = key; PGPPublicKey modified = key;
PGPSignature selfCert = null, revocation = null; PGPSignature selfCert = null, revocation = null;
for (PGPSignature zig : new IterableIterator<PGPSignature>(key.getSignatures())) { uids: for (PGPSignature zig : new IterableIterator<PGPSignature>(key.getSignatures())) {
// remove from keyring (for now) // remove from keyring (for now)
modified = PGPPublicKey.removeCertification(modified, zig); modified = PGPPublicKey.removeCertification(modified, zig);
// add this too, easier than adding it for every single "continue" case
removedCerts += 1;
WrappedSignature cert = new WrappedSignature(zig); WrappedSignature cert = new WrappedSignature(zig);
int type = cert.getSignatureType(); int type = cert.getSignatureType();
@ -467,7 +472,6 @@ public class UncachedKeyRing {
} }
if (type == PGPSignature.SUBKEY_BINDING) { if (type == PGPSignature.SUBKEY_BINDING) {
// TODO verify primary key binding signature for signing keys!
// make sure the certificate checks out // make sure the certificate checks out
try { try {
@ -481,10 +485,42 @@ public class UncachedKeyRing {
continue; continue;
} }
if (zig.getHashedSubPackets().hasSubpacket(SignatureSubpacketTags.KEY_FLAGS)) {
int flags = ((KeyFlags) zig.getHashedSubPackets()
.getSubpacket(SignatureSubpacketTags.KEY_FLAGS)).getFlags();
// If this subkey is allowed to sign data,
if ((flags & PGPKeyFlags.CAN_SIGN) == PGPKeyFlags.CAN_SIGN) {
try {
PGPSignatureList list = zig.getUnhashedSubPackets().getEmbeddedSignatures();
boolean ok = false;
for (int i = 0; i < list.size(); i++) {
WrappedSignature subsig = new WrappedSignature(list.get(i));
if (subsig.getSignatureType() == PGPSignature.PRIMARYKEY_BINDING) {
subsig.init(key);
if (subsig.verifySignature(masterKey, key)) {
ok = true;
} else {
log.add(LogLevel.WARN, LogType.MSG_KC_SUB_PRIMARY_BAD, null, indent);
continue uids;
}
}
}
if (!ok) {
log.add(LogLevel.WARN, LogType.MSG_KC_SUB_PRIMARY_NONE, null, indent);
continue;
}
} catch (Exception e) {
log.add(LogLevel.WARN, LogType.MSG_KC_SUB_PRIMARY_BAD_ERR, null, indent);
continue;
}
}
}
// if we already have a cert, and this one is not newer: skip it // if we already have a cert, and this one is not newer: skip it
if (selfCert != null && selfCert.getCreationTime().before(cert.getCreationTime())) { if (selfCert != null && selfCert.getCreationTime().before(cert.getCreationTime())) {
continue; continue;
} }
selfCert = zig; selfCert = zig;
// if this is newer than a possibly existing revocation, drop that one // if this is newer than a possibly existing revocation, drop that one
if (revocation != null && selfCert.getCreationTime().after(revocation.getCreationTime())) { if (revocation != null && selfCert.getCreationTime().after(revocation.getCreationTime())) {
@ -525,9 +561,11 @@ public class UncachedKeyRing {
// re-add certification // re-add certification
modified = PGPPublicKey.addCertification(modified, selfCert); modified = PGPPublicKey.addCertification(modified, selfCert);
removedCerts -= 1;
// add revocation, if any // add revocation, if any
if (revocation != null) { if (revocation != null) {
modified = PGPPublicKey.addCertification(modified, revocation); modified = PGPPublicKey.addCertification(modified, revocation);
removedCerts -= 1;
} }
// replace pubkey in keyring // replace pubkey in keyring
ring = PGPPublicKeyRing.insertPublicKey(ring, modified); ring = PGPPublicKeyRing.insertPublicKey(ring, modified);

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@ -169,6 +169,9 @@ public class OperationResultParcel implements Parcelable {
MSG_KC_SUB_BAD_KEYID(R.string.msg_kc_sub_bad_keyid), MSG_KC_SUB_BAD_KEYID(R.string.msg_kc_sub_bad_keyid),
MSG_KC_SUB_BAD_TIME(R.string.msg_kc_sub_bad_time), MSG_KC_SUB_BAD_TIME(R.string.msg_kc_sub_bad_time),
MSG_KC_SUB_BAD_TYPE(R.string.msg_kc_sub_bad_type), MSG_KC_SUB_BAD_TYPE(R.string.msg_kc_sub_bad_type),
MSG_KC_SUB_PRIMARY_BAD(R.string.msg_kc_sub_primary_bad),
MSG_KC_SUB_PRIMARY_BAD_ERR(R.string.msg_kc_sub_primary_bad_err),
MSG_KC_SUB_PRIMARY_NONE(R.string.msg_kc_sub_primary_none),
MSG_KC_SUB_NO_CERT(R.string.msg_kc_sub_no_cert), MSG_KC_SUB_NO_CERT(R.string.msg_kc_sub_no_cert),
MSG_KC_SUB_REVOKE_BAD_ERR (R.string.msg_kc_sub_revoke_bad_err), MSG_KC_SUB_REVOKE_BAD_ERR (R.string.msg_kc_sub_revoke_bad_err),
MSG_KC_SUB_REVOKE_BAD (R.string.msg_kc_sub_revoke_bad), MSG_KC_SUB_REVOKE_BAD (R.string.msg_kc_sub_revoke_bad),

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@ -514,8 +514,8 @@
<string name="msg_ip_fail_op_ex">Operation failed due to database error</string> <string name="msg_ip_fail_op_ex">Operation failed due to database error</string>
<string name="msg_ip_fail_remote_ex">Operation failed due to internal error</string> <string name="msg_ip_fail_remote_ex">Operation failed due to internal error</string>
<string name="msg_ip">Importing public keyring %s</string> <string name="msg_ip">Importing public keyring %s</string>
<string name="msg_ip_insert_keyring">Inserting keyring data</string> <string name="msg_ip_insert_keyring">Encoding keyring data</string>
<string name="msg_ip_insert_subkeys">Inserting subkeys</string> <string name="msg_ip_insert_subkeys">Evaluating subkeys</string>
<string name="msg_ip_prepare">Preparing database operations</string> <string name="msg_ip_prepare">Preparing database operations</string>
<string name="msg_ip_prepare_success">OK</string> <string name="msg_ip_prepare_success">OK</string>
<string name="msg_ip_preserving_secret">Preserving available secret key</string> <string name="msg_ip_preserving_secret">Preserving available secret key</string>
@ -570,6 +570,9 @@
<string name="msg_kc_sub_bad_keyid">Subkey binding issuer id mismatch</string> <string name="msg_kc_sub_bad_keyid">Subkey binding issuer id mismatch</string>
<string name="msg_kc_sub_bad_time">Removing subkey binding certificate with future timestamp</string> <string name="msg_kc_sub_bad_time">Removing subkey binding certificate with future timestamp</string>
<string name="msg_kc_sub_bad_type">Unknown subkey certificate type: %s</string> <string name="msg_kc_sub_bad_type">Unknown subkey certificate type: %s</string>
<string name="msg_kc_sub_primary_bad">Removing subkey binding certificate due to invalid primary binding certificate</string>
<string name="msg_kc_sub_primary_bad_err">Removing subkey binding certificate due to bad primary binding certificate</string>
<string name="msg_kc_sub_primary_none">Removing subkey binding certificate due to missing primary binding certificate</string>
<string name="msg_kc_sub_no_cert">No valid certificate found for %s, removing from ring</string> <string name="msg_kc_sub_no_cert">No valid certificate found for %s, removing from ring</string>
<string name="msg_kc_sub_revoke_bad_err">Removing bad subkey revocation key</string> <string name="msg_kc_sub_revoke_bad_err">Removing bad subkey revocation key</string>
<string name="msg_kc_sub_revoke_bad">Removing bad subkey revocation key</string> <string name="msg_kc_sub_revoke_bad">Removing bad subkey revocation key</string>