425 Unordered Collection - existed only in draft
444 No Response - Nginx 449 Retry With - Microsoft 450 Blocked by Windows Parental Controls - Microsoft 499 Client Closed Request - Nginx
Raised on redirection, only occurs when redirect
option for HTTP is false
.
Indicates a failure to resolve a name or address.
This Gem::StreamUI
subclass records input and output to StringIO
for retrieval during tests.
Given a set of Gem::Dependency
objects as needed
and a way to query the set of available specs via set
, calculates a set of ActivationRequest
objects which indicate all the specs that should be activated to meet the all the requirements.
Raised by Encoding
and String
methods when the source encoding is incompatible with the target encoding.
A representation of a C function
@libc = Fiddle.dlopen "/lib/libc.so.6" #=> #<Fiddle::Handle:0x00000001d7a8d8> f = Fiddle::Function.new( @libc['strcpy'], [Fiddle::TYPE_VOIDP, Fiddle::TYPE_VOIDP], Fiddle::TYPE_VOIDP) #=> #<Fiddle::Function:0x00000001d8ee00> buff = "000" #=> "000" str = f.call(buff, "123") #=> #<Fiddle::Pointer:0x00000001d0c380 ptr=0x000000018a21b8 size=0 free=0x00000000000000> str.to_s => "123"
@libc = Fiddle.dlopen "/lib/libc.so.6" #=> #<Fiddle::Handle:0x00000001d7a8d8> f = Fiddle::Function.new(@libc['strcpy'], [TYPE_VOIDP, TYPE_VOIDP], TYPE_VOIDP) #=> #<Fiddle::Function:0x00000001d8ee00> f.abi == Fiddle::Function::DEFAULT #=> true
Used internally by Fiddle::Importer
A base class for objects representing a C structure
A base class for objects representing a C union
Wrapper for arrays within a struct
A pointer to a C structure
A pointer to a C union
The base exception for JSON
errors.
This exception is raised if the nesting of parsed data structures is too deep.
This exception is raised if the required unicode support is missing on the system. Usually this means that the iconv library is not installed.
OpenSSL::Digest
allows you to compute message digests (sometimes interchangeably called “hashes”) of arbitrary data that are cryptographically secure, i.e. a Digest
implements a secure one-way function.
One-way functions offer some useful properties. E.g. given two distinct inputs the probability that both yield the same output is highly unlikely. Combined with the fact that every message digest algorithm has a fixed-length output of just a few bytes, digests are often used to create unique identifiers for arbitrary data. A common example is the creation of a unique id for binary documents that are stored in a database.
Another useful characteristic of one-way functions (and thus the name) is that given a digest there is no indication about the original data that produced it, i.e. the only way to identify the original input is to “brute-force” through every possible combination of inputs.
These characteristics make one-way functions also ideal companions for public key signature algorithms: instead of signing an entire document, first a hash of the document is produced with a considerably faster message digest algorithm and only the few bytes of its output need to be signed using the slower public key algorithm. To validate the integrity of a signed document, it suffices to re-compute the hash and verify that it is equal to that in the signature.
You can get a list of all digest algorithms supported on your system by running this command in your terminal:
openssl list -digest-algorithms
Among the OpenSSL
1.1.1 supported message digest algorithms are:
SHA224, SHA256, SHA384, SHA512, SHA512-224 and SHA512-256
SHA3-224, SHA3-256, SHA3-384 and SHA3-512
BLAKE2s256 and BLAKE2b512
Each of these algorithms can be instantiated using the name:
digest = OpenSSL::Digest.new('SHA256')
“Breaking” a message digest algorithm means defying its one-way function characteristics, i.e. producing a collision or finding a way to get to the original data by means that are more efficient than brute-forcing etc. Most of the supported digest algorithms can be considered broken in this sense, even the very popular MD5 and SHA1 algorithms. Should security be your highest concern, then you should probably rely on SHA224, SHA256, SHA384 or SHA512.
data = File.read('document') sha256 = OpenSSL::Digest.new('SHA256') digest = sha256.digest(data)
data1 = File.read('file1') data2 = File.read('file2') data3 = File.read('file3') sha256 = OpenSSL::Digest.new('SHA256') sha256 << data1 sha256 << data2 sha256 << data3 digest = sha256.digest
Digest
instance data1 = File.read('file1') sha256 = OpenSSL::Digest.new('SHA256') digest1 = sha256.digest(data1) data2 = File.read('file2') sha256.reset digest2 = sha256.digest(data2)
Generic error, common for all classes under OpenSSL
module