diff options
Diffstat (limited to 'java/com/android/voicemailomtp/mail/store/ImapConnection.java')
-rw-r--r-- | java/com/android/voicemailomtp/mail/store/ImapConnection.java | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/java/com/android/voicemailomtp/mail/store/ImapConnection.java b/java/com/android/voicemailomtp/mail/store/ImapConnection.java new file mode 100644 index 000000000..61dcf1281 --- /dev/null +++ b/java/com/android/voicemailomtp/mail/store/ImapConnection.java @@ -0,0 +1,413 @@ +/* + * Copyright (C) 2015 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package com.android.voicemailomtp.mail.store; + +import android.util.ArraySet; +import android.util.Base64; +import com.android.voicemailomtp.mail.AuthenticationFailedException; +import com.android.voicemailomtp.mail.CertificateValidationException; +import com.android.voicemailomtp.mail.MailTransport; +import com.android.voicemailomtp.mail.MessagingException; +import com.android.voicemailomtp.mail.store.ImapStore.ImapException; +import com.android.voicemailomtp.mail.store.imap.DigestMd5Utils; +import com.android.voicemailomtp.mail.store.imap.ImapConstants; +import com.android.voicemailomtp.mail.store.imap.ImapResponse; +import com.android.voicemailomtp.mail.store.imap.ImapResponseParser; +import com.android.voicemailomtp.mail.store.imap.ImapUtility; +import com.android.voicemailomtp.mail.utils.LogUtils; +import com.android.voicemailomtp.OmtpEvents; +import com.android.voicemailomtp.VvmLog; +import java.io.IOException; +import java.util.ArrayList; +import java.util.List; +import java.util.Map; +import java.util.Set; +import java.util.concurrent.atomic.AtomicInteger; +import javax.net.ssl.SSLException; + +/** + * A cacheable class that stores the details for a single IMAP connection. + */ +public class ImapConnection { + private final String TAG = "ImapConnection"; + + private String mLoginPhrase; + private ImapStore mImapStore; + private MailTransport mTransport; + private ImapResponseParser mParser; + private Set<String> mCapabilities = new ArraySet<>(); + + static final String IMAP_REDACTED_LOG = "[IMAP command redacted]"; + + /** + * Next tag to use. All connections associated to the same ImapStore instance share the same + * counter to make tests simpler. + * (Some of the tests involve multiple connections but only have a single counter to track the + * tag.) + */ + private final AtomicInteger mNextCommandTag = new AtomicInteger(0); + + ImapConnection(ImapStore store) { + setStore(store); + } + + void setStore(ImapStore store) { + // TODO: maybe we should throw an exception if the connection is not closed here, + // if it's not currently closed, then we won't reopen it, so if the credentials have + // changed, the connection will not be reestablished. + mImapStore = store; + mLoginPhrase = null; + } + + /** + * Generates and returns the phrase to be used for authentication. This will be a LOGIN with + * username and password. + * + * @return the login command string to sent to the IMAP server + */ + String getLoginPhrase() { + if (mLoginPhrase == null) { + if (mImapStore.getUsername() != null && mImapStore.getPassword() != null) { + // build the LOGIN string once (instead of over-and-over again.) + // apply the quoting here around the built-up password + mLoginPhrase = ImapConstants.LOGIN + " " + mImapStore.getUsername() + " " + + ImapUtility.imapQuoted(mImapStore.getPassword()); + } + } + return mLoginPhrase; + } + + public void open() throws IOException, MessagingException { + if (mTransport != null && mTransport.isOpen()) { + return; + } + + try { + // copy configuration into a clean transport, if necessary + if (mTransport == null) { + mTransport = mImapStore.cloneTransport(); + } + + mTransport.open(); + + createParser(); + + // The server should greet us with something like + // * OK IMAP4rev1 Server + // consume the response before doing anything else. + ImapResponse response = mParser.readResponse(false); + if (!response.isOk()) { + mImapStore.getImapHelper() + .handleEvent(OmtpEvents.DATA_INVALID_INITIAL_SERVER_RESPONSE); + throw new MessagingException( + MessagingException.AUTHENTICATION_FAILED_OR_SERVER_ERROR, + "Invalid server initial response"); + } + + queryCapability(); + + maybeDoStartTls(); + + // LOGIN + doLogin(); + } catch (SSLException e) { + LogUtils.d(TAG, "SSLException ", e); + mImapStore.getImapHelper().handleEvent(OmtpEvents.DATA_SSL_EXCEPTION); + throw new CertificateValidationException(e.getMessage(), e); + } catch (IOException ioe) { + LogUtils.d(TAG, "IOException", ioe); + mImapStore.getImapHelper().handleEvent(OmtpEvents.DATA_IOE_ON_OPEN); + throw ioe; + } finally { + destroyResponses(); + } + } + + void logout() { + try { + sendCommand(ImapConstants.LOGOUT, false); + if (!mParser.readResponse(true).is(0, ImapConstants.BYE)) { + VvmLog.e(TAG, "Server did not respond LOGOUT with BYE"); + } + if (!mParser.readResponse(false).isOk()) { + VvmLog.e(TAG, "Server did not respond OK after LOGOUT"); + } + } catch (IOException | MessagingException e) { + VvmLog.e(TAG, "Error while logging out:" + e); + } + } + + /** + * Closes the connection and releases all resources. This connection can not be used again + * until {@link #setStore(ImapStore)} is called. + */ + void close() { + if (mTransport != null) { + logout(); + mTransport.close(); + mTransport = null; + } + destroyResponses(); + mParser = null; + mImapStore = null; + } + + /** + * Attempts to convert the connection into secure connection. + */ + private void maybeDoStartTls() throws IOException, MessagingException { + // STARTTLS is required in the OMTP standard but not every implementation support it. + // Make sure the server does have this capability + if (hasCapability(ImapConstants.CAPABILITY_STARTTLS)) { + executeSimpleCommand(ImapConstants.STARTTLS); + mTransport.reopenTls(); + createParser(); + // The cached capabilities should be refreshed after TLS is established. + queryCapability(); + } + } + + /** + * Logs into the IMAP server + */ + private void doLogin() throws IOException, MessagingException, AuthenticationFailedException { + try { + if (mCapabilities.contains(ImapConstants.CAPABILITY_AUTH_DIGEST_MD5)) { + doDigestMd5Auth(); + } else { + executeSimpleCommand(getLoginPhrase(), true); + } + } catch (ImapException ie) { + LogUtils.d(TAG, "ImapException", ie); + String status = ie.getStatus(); + String statusMessage = ie.getStatusMessage(); + String alertText = ie.getAlertText(); + + if (ImapConstants.NO.equals(status)) { + switch (statusMessage) { + case ImapConstants.NO_UNKNOWN_USER: + mImapStore.getImapHelper().handleEvent(OmtpEvents.DATA_AUTH_UNKNOWN_USER); + break; + case ImapConstants.NO_UNKNOWN_CLIENT: + mImapStore.getImapHelper().handleEvent(OmtpEvents.DATA_AUTH_UNKNOWN_DEVICE); + break; + case ImapConstants.NO_INVALID_PASSWORD: + mImapStore.getImapHelper() + .handleEvent(OmtpEvents.DATA_AUTH_INVALID_PASSWORD); + break; + case ImapConstants.NO_MAILBOX_NOT_INITIALIZED: + mImapStore.getImapHelper() + .handleEvent(OmtpEvents.DATA_AUTH_MAILBOX_NOT_INITIALIZED); + break; + case ImapConstants.NO_SERVICE_IS_NOT_PROVISIONED: + mImapStore.getImapHelper() + .handleEvent(OmtpEvents.DATA_AUTH_SERVICE_NOT_PROVISIONED); + break; + case ImapConstants.NO_SERVICE_IS_NOT_ACTIVATED: + mImapStore.getImapHelper() + .handleEvent(OmtpEvents.DATA_AUTH_SERVICE_NOT_ACTIVATED); + break; + case ImapConstants.NO_USER_IS_BLOCKED: + mImapStore.getImapHelper() + .handleEvent(OmtpEvents.DATA_AUTH_USER_IS_BLOCKED); + break; + case ImapConstants.NO_APPLICATION_ERROR: + mImapStore.getImapHelper() + .handleEvent(OmtpEvents.DATA_REJECTED_SERVER_RESPONSE); + default: + mImapStore.getImapHelper().handleEvent(OmtpEvents.DATA_BAD_IMAP_CREDENTIAL); + } + throw new AuthenticationFailedException(alertText, ie); + } + + mImapStore.getImapHelper().handleEvent(OmtpEvents.DATA_REJECTED_SERVER_RESPONSE); + throw new MessagingException(alertText, ie); + } + } + + private void doDigestMd5Auth() throws IOException, MessagingException { + + // Initiate the authentication. + // The server will issue us a challenge, asking to run MD5 on the nonce with our password + // and other data, including the cnonce we randomly generated. + // + // C: a AUTHENTICATE DIGEST-MD5 + // S: (BASE64) realm="elwood.innosoft.com",nonce="OA6MG9tEQGm2hh",qop="auth", + // algorithm=md5-sess,charset=utf-8 + List<ImapResponse> responses = executeSimpleCommand( + ImapConstants.AUTHENTICATE + " " + ImapConstants.AUTH_DIGEST_MD5); + String decodedChallenge = decodeBase64(responses.get(0).getStringOrEmpty(0).getString()); + + Map<String, String> challenge = DigestMd5Utils.parseDigestMessage(decodedChallenge); + DigestMd5Utils.Data data = new DigestMd5Utils.Data(mImapStore, mTransport, challenge); + + String response = data.createResponse(); + // Respond to the challenge. If the server accepts it, it will reply a response-auth which + // is the MD5 of our password and the cnonce we've provided, to prove the server does know + // the password. + // + // C: (BASE64) charset=utf-8,username="chris",realm="elwood.innosoft.com", + // nonce="OA6MG9tEQGm2hh",nc=00000001,cnonce="OA6MHXh6VqTrRk", + // digest-uri="imap/elwood.innosoft.com", + // response=d388dad90d4bbd760a152321f2143af7,qop=auth + // S: (BASE64) rspauth=ea40f60335c427b5527b84dbabcdfffd + + responses = executeContinuationResponse(encodeBase64(response), true); + + // Verify response-auth. + // If failed verifyResponseAuth() will throw a MessagingException, terminating the + // connection + String decodedResponseAuth = decodeBase64(responses.get(0).getStringOrEmpty(0).getString()); + data.verifyResponseAuth(decodedResponseAuth); + + // Send a empty response to indicate we've accepted the response-auth + // + // C: (empty) + // S: a OK User logged in + executeContinuationResponse("", false); + + } + + private static String decodeBase64(String string) { + return new String(Base64.decode(string, Base64.DEFAULT)); + } + + private static String encodeBase64(String string) { + return Base64.encodeToString(string.getBytes(), Base64.NO_WRAP); + } + + private void queryCapability() throws IOException, MessagingException { + List<ImapResponse> responses = executeSimpleCommand(ImapConstants.CAPABILITY); + mCapabilities.clear(); + Set<String> disabledCapabilities = mImapStore.getImapHelper().getConfig() + .getDisabledCapabilities(); + for (ImapResponse response : responses) { + if (response.isTagged()) { + continue; + } + for (int i = 0; i < response.size(); i++) { + String capability = response.getStringOrEmpty(i).getString(); + if (disabledCapabilities != null) { + if (!disabledCapabilities.contains(capability)) { + mCapabilities.add(capability); + } + } else { + mCapabilities.add(capability); + } + } + } + + LogUtils.d(TAG, "Capabilities: " + mCapabilities.toString()); + } + + private boolean hasCapability(String capability) { + return mCapabilities.contains(capability); + } + /** + * Create an {@link ImapResponseParser} from {@code mTransport.getInputStream()} and + * set it to {@link #mParser}. + * + * If we already have an {@link ImapResponseParser}, we + * {@link #destroyResponses()} and throw it away. + */ + private void createParser() { + destroyResponses(); + mParser = new ImapResponseParser(mTransport.getInputStream()); + } + + + public void destroyResponses() { + if (mParser != null) { + mParser.destroyResponses(); + } + } + + public ImapResponse readResponse() throws IOException, MessagingException { + return mParser.readResponse(false); + } + + public List<ImapResponse> executeSimpleCommand(String command) + throws IOException, MessagingException{ + return executeSimpleCommand(command, false); + } + + /** + * Send a single command to the server. The command will be preceded by an IMAP command + * tag and followed by \r\n (caller need not supply them). + * Execute a simple command at the server, a simple command being one that is sent in a single + * line of text + * + * @param command the command to send to the server + * @param sensitive whether the command should be redacted in logs (used for login) + * @return a list of ImapResponses + * @throws IOException + * @throws MessagingException + */ + public List<ImapResponse> executeSimpleCommand(String command, boolean sensitive) + throws IOException, MessagingException { + // TODO: It may be nice to catch IOExceptions and close the connection here. + // Currently, we expect callers to do that, but if they fail to we'll be in a broken state. + sendCommand(command, sensitive); + return getCommandResponses(); + } + + public String sendCommand(String command, boolean sensitive) + throws IOException, MessagingException { + open(); + + if (mTransport == null) { + throw new IOException("Null transport"); + } + String tag = Integer.toString(mNextCommandTag.incrementAndGet()); + String commandToSend = tag + " " + command; + mTransport.writeLine(commandToSend, (sensitive ? IMAP_REDACTED_LOG : command)); + return tag; + } + + List<ImapResponse> executeContinuationResponse(String response, boolean sensitive) + throws IOException, MessagingException { + mTransport.writeLine(response, (sensitive ? IMAP_REDACTED_LOG : response)); + return getCommandResponses(); + } + + /** + * Read and return all of the responses from the most recent command sent to the server + * + * @return a list of ImapResponses + * @throws IOException + * @throws MessagingException + */ + List<ImapResponse> getCommandResponses() + throws IOException, MessagingException { + final List<ImapResponse> responses = new ArrayList<ImapResponse>(); + ImapResponse response; + do { + response = mParser.readResponse(false); + responses.add(response); + } while (!(response.isTagged() || response.isContinuationRequest())); + + if (!(response.isOk() || response.isContinuationRequest())) { + final String toString = response.toString(); + final String status = response.getStatusOrEmpty().getString(); + final String statusMessage = response.getStatusResponseTextOrEmpty().getString(); + final String alert = response.getAlertTextOrEmpty().getString(); + final String responseCode = response.getResponseCodeOrEmpty().getString(); + destroyResponses(); + throw new ImapException(toString, status, statusMessage, alert, responseCode); + } + return responses; + } +} |