Commit Graph
100 Commits
Author SHA1 Message Date
Markus Triska 4a90f13dee better error handling for options 2020-07-23 00:27:31 +02:00
Markus Triska 61dddcee3f use newly available chars_base64/3 2020-07-22 20:35:48 +02:00
Markus Triska 4c510001ce ADDED: chars_base64/3 for efficient bidirectional Base64 conversion. 2020-07-22 20:35:48 +02:00
Markus Triska 2768beec4c ADDED: path_segments/2 for portable reasoning about path components.
The platform-specific directory separator is taken into account.
The clean representation of segments as a list simplifies reasoning.
2020-07-19 12:32:01 +02:00
Markus Triska c9a69263b6 DOC: add more links to libraries, and include iso_ext in the enumeration 2020-07-18 08:12:26 +02:00
Markus Triska 17dd9239b6 ADDED: file_creation_time/2 and file_access_time/2.
The code can be simplified once if- and while-let-chains are available:

    https://github.com/rust-lang/rust/issues/53667
2020-07-17 18:48:39 +02:00
Markus Triska 8668aee7fd ENHANCED: Reorder fields in time stamps so that (@<)/2 is meaningful. 2020-07-16 23:40:03 +02:00
Markus Triska 4f386b3e5e ADDED: file_modification_time/2, obtaining a time stamp.
This addresses a remaining aspect of #511.
2020-07-16 23:40:03 +02:00
Markus Triska 0f4667d942 ADDED: path_canonical/2, obtaining the canonical absolute path.
This addresses a remaining aspect of #511.
2020-07-15 20:43:34 +02:00
Markus Triska 94e9e17c79 ADDED: working_directory/2, addressing a remaining aspect of #511 2020-07-14 23:05:29 +02:00
Markus Triska 5134e64cae ADDED: delete_file/1, addressing a remaining aspect of #511 2020-07-14 22:21:46 +02:00
Markus Triska b227e160f0 mention symmetric encryption and ChaCha20-Poly1305 2020-07-12 11:59:34 +02:00
Markus Triska 88a2b82f7e ENHANCED: library(crypto): Retain the compact representation of strings.
This avoids the costly (in terms of space requirements!) conversion of
compact lists of characters to lists of integers, making hashing, HKDF,
encryption, decryption, signing and signature verification an order of
magnitude more efficient (primarily in terms of space, also in time).

This makes library(crypto) suitable to process also very large files.
2020-07-12 11:54:37 +02:00
Markus Triska 0fa8feb475 use newly available character type in must_be/2 2020-07-11 21:00:25 +02:00
Markus Triska eb872f8fca ADDED: library(os), reasoning about environment variables.
Together with library(files), this addresses #511.
2020-07-11 21:00:25 +02:00
Markus Triska 65f200e02c directory_files/2: throw representation error if into_string() fails
Suggested by @notoria in #606. Many thanks!
2020-06-24 23:30:40 +02:00
Markus Triska aa9432e24f comment on indexing, addressing a comment by @pmoura in #606
If indexing is needed for lists of characters, it should be added to
the engine.
2020-06-24 22:29:34 +02:00
Markus Triska 30d1585468 ADDED: library(files), for reasoning about files and directories. 2020-06-24 22:29:34 +02:00
Markus Triska bcd6d4e8a7 library(format) is not used in this example 2020-06-21 09:46:05 +02:00
Markus Triska 32eb896c56 ADDED: load_xml/3 to load XML files from streams, files and strings. 2020-06-21 09:45:37 +02:00
Markus Triska b3c9fb2fea import member/2 from library(lists)
This is needed when processing redirects.
2020-06-20 19:07:43 +02:00
Markus Triska d66ea07ba4 ADDED: library(xpath) for convenient analysis of HTML and XML documents. 2020-06-20 18:08:11 +02:00
Markus Triska 79829cb6d2 ADDED: library(sgml), providing load_html/3 to parse HTML documents 2020-06-19 16:40:01 +02:00
Markus Triska 5eda2dfe0e put_char/[1,2]: throw type errors for atoms that are not characters
Example:

    ?- put_char(hello).
    %@ caught: error(type_error(character,hello),put_char/2)
2020-06-18 00:15:00 +02:00
Markus Triska 19acd608a5 ADDED: library(http/http_open), opening HTTP and HTTPS streams for reading
Example:

   ?- http_open("https://github.com/mthom/scryer-prolog", Stream, []),
      length(Ls, 10),
      maplist(get_char(Stream), Ls).

Yielding:

   %@    Stream = '$stream'(0x7fba4c59ef10), Ls = "\n\n\n\n\n<!DOC"
   %@ ;  false.
2020-06-17 20:10:22 +02:00
Markus Triska 8958ea036e ENHANCED: much faster format/3 for text streams
This is now also used by format/2 to emit output on the terminal,
and significantly speeds up toplevel output of long strings.
2020-06-16 21:13:03 +02:00
Markus Triska 10a0f708b9 use format/3 to benefit from efficiency improvements 2020-06-14 10:51:24 +02:00
Markus Triska 409d3c168d ENHANCED: faster format/3 when writing to binary streams
This is also more secure, since it does not change the atom table
and therefore leaves little trace of what was processed.
2020-06-14 10:43:25 +02:00
Markus Triska f910e013a6 use take() for extra fast processing of binary files
Suggested by @notoria in #589. Many thanks!
2020-06-13 16:47:46 +02:00
Markus Triska 5f1b03261c better naming: str --> string
Suggested by @notoria in #589. Many thanks!
2020-06-13 16:47:46 +02:00
Markus Triska 862197fc96 explain .scryerrc configuration file 2020-06-13 16:47:02 +02:00
Markus Triska 44ebd894d5 ADDED: portray_clause/2, writing to a specified stream. 2020-06-13 16:45:47 +02:00
Markus Triska b85ff7db36 ENHANCED: Read more characters at once, significantly speeding up library(pio). 2020-06-13 16:25:41 +02:00
Markus Triska 22fd216de5 ADDED: read_line_to_chars/3, reading up to and including "\n" from a stream, yielding a list difference.
This works for both binary and text streams.
2020-06-13 09:14:44 +02:00
Markus Triska d96ea6b815 include library(pio) and library(charsio) in the itemization 2020-06-12 00:02:41 +02:00
Markus Triska 40c3e31955 ENHANCED: phrase_from_file/[2,3] now read the file lazily.
This allows processing extremely large files. In addition, the
efficient string representation helps to reduce memory usage.

These features unleash the full power of Prolog for text processing,
the exact use case Prolog was designed for.
2020-06-12 00:02:41 +02:00
Markus Triska 2fc887724b ADDED: format_time//2 for describing strings involving dates and times
current_time/1 yields the current system time as an opaque time stamp.
2020-06-11 00:55:38 +02:00
Markus Triska 184ef94e7e ENHANCED: throw Prolog exception on expired certificates
Example:

    ?- socket_client_open('expired.badssl.com':443, S, [tls(true)]).
    caught: error(permission_error(open,source_sink,'expired.badssl.com'),socket_client_open/3)
2020-06-09 23:01:28 +02:00
Markus Triska 7b30daf88d ADDED: Encrypted client connections in library(sockets) via new option tls/1.
Use tls(true) to negotiate an encrypted network connection via TLS.
2020-06-09 07:43:29 +02:00
Markus Triska d5e76da475 ADDED: type checks for type boolean 2020-06-08 00:41:47 +02:00
Markus Triska c22816de08 type check for ~d and ~D specifiers 2020-06-08 00:09:55 +02:00
Markus Triska 9bb851d437 ENHANCED: format_//2 now evaluates arithmetic expressions for ~d, ~D, ~f, ~r and ~R
Example:

    ?- phrase(format_("~d", [1+2]), Cs).
       Cs = "3"
    ;  false.
2020-06-08 00:09:55 +02:00
Markus Triska c8a9f8dcf5 better domain error in format_//2
Example:

    ?- format("", [hello]).
    caught: error(domain_error(empty_list,[hello]),format_//2)
2020-06-07 23:59:37 +02:00
Markus Triska e8653ffe32 add type check for scalar argument in crypto_curve_scalar_mult/4
Suggested by @notoria in #576. Many thanks!
2020-06-07 18:51:13 +02:00
Markus Triska 5499df418a use secp256k1 in the example 2020-06-07 11:04:24 +02:00
Markus Triska b586618411 ENHANCED: Faster Rust-based crypto_curve_scalar_mult/4 using OpenSSL. 2020-06-07 11:04:24 +02:00
Markus Triska 7cc92ec1c1 ADDED: Logo.
Motivation and considerations:

- A Scryer certainly needs a raven. Ravens are among the most
  intelligent animals on earth.
- When writing Prolog programs, a few strokes are often enough.
- Purple is the colour most associated with magic and royalty,
  indicating the almost surreal and pure features provided by Scryer,
  in the lineage of Marseille Prolog.
- The shape of the silhouette looks a bit like an "S" for "Scryer".
- A square which surrounds the image is traditionally associated with
  finishing a proof (square, Latin "quadratum", has the same starting
  letters as "quod erat demonstrandum").

I call this raven: *Cryer*. Cryer is an archaic spelling for "crier",
an officer who makes public announcements in a court of justice.
The Prolog top-level likewise makes announcements about what is true.
2020-05-26 22:13:51 +02:00
Markus Triska b0df981b01 ADDED: halt/1, halting with specified exit code 2020-05-23 19:28:17 +02:00
Markus Triska 48c0b0ab3c ENHANCED: Faster format/3 for binary streams.
This speeds up web servers considerably when sending binary files.
2020-05-22 17:30:29 +02:00
Markus Triska cbbed310c5 ADDED: format/3, writing formatted output to a stream
Both binary and text streams are supported.
2020-05-22 17:23:51 +02:00
Markus Triska 1108c99688 document that lists of integers can be specified if encoding(octet) is used
This seems to be a good compromise: The API now strongly encourages
lists of characters, which are ideally suited to represent text, and
also allows lists of bytes if the encoding(octet) option is used.
2020-05-21 13:41:57 +02:00
Markus Triska 93da831ef0 correct mode indication for ed25519_verify/4
Noted by @notoria in #545. Many thanks!
2020-05-21 01:27:06 +02:00
Markus Triska 72bf45912e "PrivateKey" --> "KeyPair" 2020-05-21 00:14:15 +02:00
Markus Triska 5d94276c4f remove several mentions of list of bytes in predicate descriptions
This is to focus more on the intended core representation of text: In
Prolog, text is ideally represented as a list of characters, and this
is what we want to encourage, especially given Scryer's compact
representation for strings.

For the time being, library(crypto) still also supports lists of bytes in
several predicates. This will likely be removed at some point in the
future. Please use lists of characters to make your code future-proof.
2020-05-21 00:07:42 +02:00
Markus Triska b43f27030e require PKCS#8 v2 format for better security
Notably, this format requires that the public key also be present.
This format is what ed25519_new_keypair/1 generates, and it is
strongly encouraged for higher security.
2020-05-20 23:55:21 +02:00
Markus Triska 2845f55157 ADDED: ed25519_keypair_public_key/2, relating a key pair to its public key 2020-05-20 23:43:28 +02:00
Markus Triska e254d84710 clarify format of public key 2020-05-20 23:17:42 +02:00
Markus Triska 0ef7b5488d ADDED: ed25519_new_keypair/1 to dynamically create a new Ed25519 key pair 2020-05-20 23:11:56 +02:00
Markus Triska 56b04f8df8 use LessSafeKey to simplify the implementation of authenticated encryption
The nonce is explicitly specified, and the application programmer
must (and always had to) ensure that it is unique for a given key.
2020-05-20 22:32:39 +02:00
Markus Triska 2d036c6b25 "codes" --> "bytes"
Support for lists of bytes may be dropped from library(crypto). Use
lists of characters to make your code future-proof. Lists of
characters will always be supported due to their compactness,
and because Prolog applications should move towards characters.
2020-05-20 22:32:39 +02:00
Markus Triska ad3be5c848 ADDED: Public key signatures and signature verification with Ed25519 2020-05-20 22:32:39 +02:00
Markus Triska 21b7348c6a import member/2 from library(lists) 2020-05-19 20:13:06 +02:00
Markus Triska 0bd9831eec ADDED: phrase_from_file/3 in library(pio)
This allows us to specify type(binary), and read from binary files
with DCGs.
2020-05-19 18:52:18 +02:00
Markus Triska dec2ef70c7 better error handling in crypto_data_hkdf/4
Noted by @notoria in #533. Many thanks!
2020-05-19 18:22:25 +02:00
Markus Triska d19d8ea770 crypto_data_hkdf/4: do not crash for length > usize::max_value()
For now, we fail silently in such cases.

Noted by @notoria in #533. Many thanks!
2020-05-19 17:31:36 +02:00
Markus Triska 34f7752c0f use more fixnums in cryptographic routines 2020-05-19 17:03:02 +02:00
Markus Triska da4d061067 correct option processing in crypto_data_decrypt/6 2020-05-19 17:02:33 +02:00
Markus Triska 85155439be use Fixnums for bytes in hashing.
Suggested by @notoria in #533. Many thanks!
2020-05-19 16:43:44 +02:00
Markus Triska dd32e69061 use matching to select the hashing algorithm
Suggested by @notoria in #533. Many thanks!
2020-05-19 16:37:50 +02:00
Markus Triska 9f5322d309 ADDED: Support for BLAKE2 algorithms in crypto_data_hash/3. 2020-05-19 12:44:10 +02:00
Markus Triska f5c2f6f9e9 ADDED: Support for SHA-3 algorithms in crypto_data_hash/3 2020-05-19 12:10:46 +02:00
Markus Triska a423eb5323 stronger validation of input lists for cryptographic routines
Example:

    ?- crypto_data_hkdf(Var, 32, Bs, []).
    caught: error(instantiation_error,must_be/2)

Reported by @notoria in #527. Many thanks!
2020-05-18 13:28:52 +02:00
Markus Triska fd732550d8 crypto_data_hkdf/4: Fail if the length is too long.
Due to the way the counter is constructed in the HKDF specification,
the requested output length can be at most 255 times the size of the
digest algorithm's output.

Reported by @notoria in #527. Many thanks!
2020-05-18 13:21:38 +02:00
Markus Triska fac7ba70c8 crypto_password_hash/3: fail if the number of iterations is too high
Discussed in #527.
2020-05-18 13:11:39 +02:00
Markus Triska e9f8b35918 centralize reasoning about encoding 2020-05-18 11:29:35 +02:00
Markus Triska 23034dd4f5 raise instantiation errors for variable encoding
Reported by notoria in #527.

Note that from a declarative perspective, it would indeed be valid to
give answers for both available encodings.
2020-05-18 11:21:38 +02:00
Markus Triska 70ad44adfd type check for length argument in crypto_data_hkdf/4
Reported by @notoria in #527.
2020-05-18 11:12:59 +02:00
Markus Triska 95ca8a2630 throw instantiation error if the list of options contains a variable (#523)
Many thanks to @notoria for the test case!
2020-05-18 09:58:09 +02:00
Markus Triska 3855d7ea02 type test for salt in crypto_password_hash/3 2020-05-17 22:01:22 +02:00
Markus Triska 862ae26631 Authenticated encryption in library(crypto), new encoding/1 option for hashes (#515)
* shorten n_newlines//1

* remove unneeded variable

* ADDED: authenticated encryption and decryption with ChaCha20-Poly1305

* ADDED: encoding/1 option for crypto_data_hash/3 and crypto_data_hkdf/4
2020-05-16 11:51:41 -06:00
Markus Triska 4e69301562 ADDED: Password-based key derivation (PBKDF2) (#509)
The new predicates crypto_password_hash/[2,3] let you store
passwords safely, and easily verify passwords later.
2020-05-15 10:49:23 -06:00
Markus Triska 50776748a7 ADDED: HMAC-based key derivation (HKDF) via crypto_data_hkdf/4
This is useful to generate keys and initialization vectors
from suitable input keying material, so that future predicates
for symmetric encryption can be used with appropriate parameters.
2020-05-14 20:07:59 +02:00
Markus Triska 4084005ee7 ADDED: Reasoning about elliptic curves in library(crypto).
This is useful to establish shared secrets, using ECDH key exchange.

Note that CLP(ℤ) goal expansion is currently disabled due to #445,
and this slows down the computations considerably for the time being.
2020-05-13 22:44:27 +02:00
Markus Triska fd761735d4 ADDED: ripemd160 digest algorithm
This is used for example for Bitcoin address generation.
2020-05-13 22:36:40 +02:00
Markus Triska 8cd7d08573 ADDED: crypto_data_hash/3, computing cryptographically secure digests 2020-05-13 19:23:09 +02:00
Markus Triska 716fde5784 ADDED: crypto_n_random_bytes/2, creating cryptographically secure random bytes
The ring crate is used since it will be needed also for future
predicates in library(crypto).
2020-05-13 00:36:27 +02:00
Markus Triska d75449ea63 ADDED: ~Nr and ~NR are now available for radix conversions 2020-05-09 19:19:25 +02:00
Markus Triska a131c93a14 ADDED: Initial version of library(crypto). 2020-05-08 22:33:49 +02:00
Markus Triska 2dfdaaa4ba disable goal expansion until #445 is resolved 2020-05-04 18:55:52 +02:00
Markus Triska 605c233753 do not project queue/2 attributes to residual goals 2020-05-04 00:54:43 +02:00
Markus Triska ec6d725587 use ℤ
This is now possible thanks to the great contribution by @matt2xu.

Many thanks!
2020-05-02 00:06:16 +02:00
Markus Triska ca5a5b4392 correct overeager CLP(ℤ) goal expansion
For instance, consider:

    t(X) :- X #= 1.

We *cannot* expand this to:

    ?- listing(t/1).
    t(A) :-
       (  integer(A) ->
          A=:=A
       ;  (  var(A) ->
             true
          ;  true,
             clpz:clpz_equal(A,A)
          )
       ).

Also, a new binding *must not* be dragged outside of disjunctions,
since the code may look for example like this:

        i(X) :-
            (   X #= 3
            ;   X #= 4
            ).

This commit fixes such issues, and still rewrites CLP(ℤ) expressions
as far as possible already at compilation time.

For example:

    n(X) :- X #= 1+3.

This is now compiled to (note that 1+3 is evaluated to 4):

    ?- listing(n/1).
    n(A) :-
       (  integer(A) ->
          A=:=4
       ;  (  var(A) ->
             A=4
          ;  B=4,
             clpz:clpz_equal(A,B)
          )
       ).

Ideally, it should be compiled to:

    n(4).
2020-05-01 18:29:00 +02:00
Markus Triska 1dbadbfc35 enable goal expansion for CLP(ℤ) goals
Example:

    integer_successor(I0, I) :- I #= I0 + 1.

Yielding:

    ?- listing(integer_successor/2).
    integer_successor(A,B) :-
       (  integer(B) ->
          (  integer(A) ->
             B=:=A+1
          ;  C is B,
             clpz:clpz_equal(C,A+1)
          )
       ;  (  integer(A) ->
             (  var(B) ->
                B is A+1
             ;  C is A+1,
                clpz:clpz_equal(B,C)
             )
          ;  clpz:clpz_equal(B,A+1)
          )
       ).

Thus, fast low-level arithmetic is used whenever possible.
2020-04-30 23:09:15 +02:00
Markus Triska a39f4b4487 correct verify_attributes/3 for variables that have no CLP(ℤ) attribute attached (#373)
Example:

    ?- freeze(B, queen_value_truth(C,N,B)), Q #= N #<==> B.
       clpz:(Q#=N#<==>B), clpz:(B in 0..1), freeze:freeze(B,queen_value_truth(C,N,B))
    ;  false.
2020-04-30 18:10:09 +02:00
Markus Triska b499c575bc include library(arithmetic) in the overview
Many thanks to @notoria for these very useful predicates!
2020-04-29 22:06:49 +02:00
Markus Triska 20b76a703a mention portray_clause/1 and listing/1 2020-04-28 18:27:46 +02:00
Markus Triska dcc09b7bb5 mention backtrackable and non-backtrackable global variables 2020-04-28 18:22:18 +02:00
Markus Triska 4ea0dee90a use new nth0/3 from library(lists) 2020-04-28 17:59:49 +02:00
Markus Triska e61116d35a use singleton variable, correct a mistake in maplist/8 2020-04-28 17:59:49 +02:00
Markus Triska f7256c75d5 ADDED: nth0/3, relating indices to list elements 2020-04-28 17:59:49 +02:00