8K VALID MAIL.txt

The java.net.InetAddress class has been updated to strictly accept IPv4 address literals in decimal quad notation. The InetAddress class methods are updated to throw an java.net.UnknownHostException for invalid IPv4 address literals. To disable this check, the new "jdk.net.allowAmbiguousIPAddressLiterals" system property can be set to "true".

8K VALID MAIL.txt

In "compat" and "strict" mode, more validation is performed. As an example, in the URL authority component, the new parsing only accepts brackets around IPv6 literal addresses. Developers are encouraged to use java.net.URI constructors or its factory method to build URLs rather than handcrafting URL strings.

Cause: In 8u261, System Property SSLSessionContext.getSessionCacheSize default value was changed from 0 to 20480 ( see JDK-8210985 ) The change was made since with larger heaps, applications are running into situations where the cache ends up with several million entries at the 24 hour mark, at which time many of them are invalidated at almost the same time, which can result in multi-minute pauses, which are effectively service failures.

New checks have been added to ensure that trust anchors are CA certificates and contain proper extensions. Trust anchors are used to validate certificate chains used in TLS and signed code. Trust anchor certificates must include a Basic Constraints extension with the cA field set to true. Also, if they include a Key Usage extension, the keyCertSign bit must be set.

TLS Server certificates issued on or before April 16, 2019 will continue to be trusted until they expire. Certificates issued after that date will be rejected. See the DigiCert support page for information on how to replace your Symantec certificates with a DigiCert certificate (DigiCert took over validation and issuance for all Symantec Website Security SSL/TLS certificates on December 1, 2017).

The secure validation mode of the XML Signature implementation has been enhanced to restrict EC keys less than 224 bits by default. The secure validation mode is enabled either by setting the property org.jcp.xml.dsig.secureValidation to true with the javax.xml.crypto.XMLCryptoContext.setProperty() method, or by running the code with a SecurityManager.

A new JDK implementation specific system property jdk.internal.FileHandlerLogging.maxLocks has been introduced to control the java.util.logging.FileHandler MAX_LOCKS limit. The default value of the current MAX_LOCKS (100) is retained if this new system property is not set or an invalid value is provided to the property. Valid values for this property are integers ranging from 1 to Integer.MAX_VALUE-1.

In 8u161, the RSA implementation in the SunRsaSign provider will reject any RSA public key that has an exponent that is not in the valid range as defined by PKCS#1 version 2.2. This change will affect JSSE connections as well as applications built on JCE.

The Javadoc Standard Doclet documentation has been enhanced to specify that it doesn't validate the content of documentation comments for conformance, nor does it attempt to correct any errors in documentation comments. See the Conformance section in the Doclet documentation.

Any TLS server certificate chain containing a SHA-1 certificate (end-entity or intermediate CA) and anchored by a root CA certificate included by default in Oracle's JDK is now blocked by default. TLS Server certificate chains that are anchored by enterprise or private CAs are not affected. Only X.509 certificate chains that are validated by the PKIX implementation of the CertPathValidator and CertPathBuilder APIs and the SunX509 and PKIX implementations of the TrustManagerFactory API are subject to the restrictions. Third-party implementations of these APIs are directly responsible for enforcing their own restrictions.

Oracle Database uses one of two time zone files as the source of valid time zones. The default time zone file is timezlrg_11.dat. It contains more time zones than the smaller time zone file, timezone_11.dat.

You cannot change the block size after database creation except by re-creating the database. If the database block size is different from the operating system block size, then ensure that the database block size is a multiple of the operating system block size. For example, if your operating system block size is 2K (2048 bytes), the following setting for the DB_BLOCK_SIZE initialization parameter is valid:

UTF-8 is capable of encoding all 1,112,064[a] valid character code points in Unicode using one to four one-byte (8-bit) code units. Code points with lower numerical values, which tend to occur more frequently, are encoded using fewer bytes. It was designed for backward compatibility with ASCII: the first 128 characters of Unicode, which correspond one-to-one with ASCII, are encoded using a single byte with the same binary value as ASCII, so that valid ASCII text is valid UTF-8-encoded Unicode as well.

The standard specifies that the correct encoding of a code point uses only the minimum number of bytes required to hold the significant bits of the code point. Longer encodings are called overlong and are not valid UTF-8 representations of the code point. This rule maintains a one-to-one correspondence between code points and their valid encodings, so that there is a unique valid encoding for each code point. This ensures that string comparisons and searches are well-defined.

Many of the first UTF-8 decoders would decode these, ignoring incorrect bits and accepting overlong results. Carefully crafted invalid UTF-8 could make them either skip or create ASCII characters such as NUL, slash, or quotes. Invalid UTF-8 has been used to bypass security validations in high-profile products including Microsoft's IIS web server[29] and Apache's Tomcat servlet container.[30] RFC 3629 states "Implementations of the decoding algorithm MUST protect against decoding invalid sequences."[31] The Unicode Standard requires decoders to "...treat any ill-formed code unit sequence as an error condition. This guarantees that it will neither interpret nor emit an ill-formed code unit sequence."

Since RFC 3629 (November 2003), the high and low surrogate halves used by UTF-16 (U+D800 through U+DFFF) and code points not encodable by UTF-16 (those after U+10FFFF) are not legal Unicode values, and their UTF-8 encoding must be treated as an invalid byte sequence. Not decoding unpaired surrogate halves makes it impossible to store invalid UTF-16 (such as Windows filenames or UTF-16 that has been split between the surrogates) as UTF-8,[32] while it is possible with WTF-8.

Some implementations of decoders throw exceptions on errors.[33] This has the disadvantage that it can turn what would otherwise be harmless errors (such as a "no such file" error) into a denial of service. For instance early versions of Python 3.0 would exit immediately if the command line or environment variables contained invalid UTF-8.[34] An alternative practice is to replace errors with a replacement character. Since Unicode 6[35] (October 2010), the standard (chapter 3) has recommended a "best practice" where the error ends as soon as a disallowed byte is encountered. In these decoders E1,A0,C0 is two errors (2 bytes in the first one). This means an error is no more than three bytes long and never contains the start of a valid character, and there are 21,952 different possible errors.[36] The standard also recommends replacing each error with the replacement character "" (U+FFFD).

In August 1992, this proposal was circulated by an IBM X/Open representative to interested parties. A modification by Ken Thompson of the Plan 9 operating system group at Bell Labs made it self-synchronizing, letting a reader start anywhere and immediately detect character boundaries, at the cost of being somewhat less bit-efficient than the previous proposal. It also abandoned the use of biases and instead added the rule that only the shortest possible encoding is allowed; the additional loss in compactness is relatively insignificant, but readers now have to look out for invalid encodings to avoid reliability and especially security issues. Thompson's design was outlined on September 2, 1992, on a placemat in a New Jersey diner with Rob Pike. In the following days, Pike and Thompson implemented it and updated Plan 9 to use it throughout, and then communicated their success back to X/Open, which accepted it as the specification for FSS-UTF.[73]

In WTF-8 (Wobbly Transformation Format, 8-bit) unpaired surrogate halves (U+D800 through U+DFFF) are allowed.[94] This is necessary to store possibly-invalid UTF-16, such as Windows filenames. Many systems that deal with UTF-8 work this way without considering it a different encoding, as it is simpler.[95]

Version 3 of the Python programming language treats each byte of an invalid UTF-8 bytestream as an error (see also changes with new UTF-8 mode in Python 3.7[99]); this gives 128 different possible errors. Extensions have been created to allow any byte sequence that is assumed to be UTF-8 to be losslessly transformed to UTF-16 or UTF-32, by translating the 128 possible error bytes to reserved code points, and transforming those code points back to error bytes to output UTF-8. The most common approach is to translate the codes to U+DC80...U+DCFF which are low (trailing) surrogate values and thus "invalid" UTF-16, as used by Python's PEP 383 (or "surrogateescape") approach.[100] Another encoding called MirBSD OPTU-8/16 converts them to U+EF80...U+EFFF in a Private Use Area.[101] In either approach, the byte value is encoded in the low eight bits of the output code point.

These encodings are very useful because they avoid the need to deal with "invalid" byte strings until much later, if at all, and allow "text" and "data" byte arrays to be the same object. If a program wants to use UTF-16 internally these are required to preserve and use filenames that can use invalid UTF-8;[102] as the Windows filesystem API uses UTF-16, the need to support invalid UTF-8 is less there.[100] 041b061a72