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jml - a useful web/cloud minimal unikernel distributed operating system

C 86.90% Perl 2.24% Shell 0.46% C++ 7.97% Scilab 1.27% Emacs Lisp 1.15%
lambda-calculus language eval functional-language functional web html webserver unikernel operating-system urbit

jml's Introduction

jml - a useful web/cloud minimal unikernel distributed operating system

TODO: rename to MagniOS

Goal

Simple online-programmable virtual physical computer with built in persistent "memory" extending the IoT to simple internet/cloud computers, that are disposable scalable online reconfigurable minimal processing instances. This is an instance of a "single (minimalish) computer".

But as we know the future is distributed and we need to provide infrastructure "above a single computer". This system provides such services implemented utilizing the said single computers.

Woa!?

So crassly seen it's a html-generating programmable virtual computer with high-level lambda style "instructions". As we know, lambda calculus is "described" by subsitution, here we take the approach that actual in-place substitution constitutes a viable computer. We provide a minimal of basic services without getting stuck in the trap of generality of an operating system. All the services/functions are "not" mapped to or dependent on a UNIX computer as such. Therefore, it can be hosted on containerized physical hardware SOAC (System On A Chip) like the ESP-8266.

Services provided

(Things in parenthesis in progress..)

  • Lambda style computational engine
  • (Reliable) Messaging to remote entity
  • Dispatch of incoming messages to user define API
  • Persistent local event data store
  • Online extensible program
  • Encryption secured remote execution, and program upgrade
  • (Transferable state, movability)
  • CHORD-style distributed storage and addressing
  • (distributed service directory)
  • (distributed files and directories)

Current limitations:

  • messaging currently limited to "REST" calls, could/should use UDP for small messages, otherwise TCP/IP
  • messaging not reliable/transactionable
  • persistence not atomic per triggering event/message

It's not clear what would be missing as a minimized viable portable computing instance. If it's hardware connected to physical sensors measurement naturally it would be limited to such capable instances, often even to specific locations. Other functionality is portable, and transferable.

Handy features:

  • built in / handler
  • built in mini-wiki!
  • built in reflection
  • built in display of public /api handler and generating form/buttons for easy interaction
  • simple portable symmetric encryption (XXTEA)

First Principles

This is a First Principle's project. It means it starts from "scratch" with minimal requirements. Elon Musk uses this as his innovation principle.

For example: "In physics, a calculation is said to be from first principles, or ab initio, if it starts directly at the level of established laws of physics and does not make assumptions such as empirical model and fitting parameters." - wikipedia

Requirements

C (gcc) compiler, and simple unix style standard library calls. For "security" no external libraries are used.

HowTo Compile a 32-bit Application Using gcc On the 64-bit Linux Version

Why

The idea of a minimal OS is coming up again, maybe recently more (now is 2016) than the last 30 years. We have docker, and various virtualization environments. It's funny to simulate an actual once existing hardware computer - mostly just a IBM PC compatible. However, there are other approaches, more minimal which are single language based. These are sometimes called a library OS implementations. For example RTOS for ESP8266 esp-open-rtos can be seen as such. It provides a small implementation of most of the libraries and system calls you'd expect on a POSIX/linux style computer. It is limited to a single process, so no fork/popen or system cals. It does provide it's own threading/tasks and semaphore/messaging system. However, it doesn't provide infrastructure to think "above a single computer".

What is it?

This project is an attempt to provide a small relatively simple C program implementing a portable small language onto such an invironment. Of course, for more complicated tasks a multitude of such distributed instances would be able to cooperate in order to solve a bigger problem.

Status

Status: More "useless" than Urbit!

Outline of actions/TODO/DONE

Extentions?

It's not mean to be extended on the C-level. However, some way of accessing hardware/sensors is needed. Possibly, the most portable way to approach this is to provide the service as a minimal webrequest/mqtt interface. This would allow the sensors to be directly accessible, if secure, on external interfaces too, transparently. Indistinguishable from other mqtt/webservices devices. The "strict" goal is to keep all the code/native functions, exactly the same on all devices. In princple, after a while, we should be able to freeze them, and only work on extension on the soft-layer.

How to run

command line interactive

./run

batch

This allows a single command, or several to be run and output captured.

echo "[concat a b c]" | ./run 2>/dev/null

web

To run it as a webserve on port 1111, or as given use the command below. Connect to it as localhost:1111/.

./run -w [PORT]

simulated group of servers

./start-servers

debugging using tracing

unix> echo "[+ [map inc 1 2 3]]" | ./run -t
>>>[+ [map inc 1 2 3]]<<<
>>>[+ [inc 1] [inc 2] [inc 3] ]<<<
>>>[+ 2 3 4 ]<<<
>>>9<<<
9


unix> echo '[macro fac $n][* [iota 1 $n]][/macro]' | ./run
  [appended fac to file]

unix> echo "[fac 5]" | ./run -t
>>>[fac 5]<<<
>>>[* [iota 1 5]]<<<
>>>[* 1 2 3 4 5 ]<<<
>>>120<<<
120

options for performance/info

-q       == quiet mode, only writes %%error messages
-w       == normal mode, start webserver
-v       == log timing and reductions info
-v -v    == log reallocs
-v -v -v == log allocs too

Language

The language is a bastard variant of lambda calculus where the evalution is eager, and evaluation is performed by plain textual substitution. There are no variables as such, no stack, no closure, no circular data structures, no data structures. Semantics of our langauges is specified by legal substitutions. We find any "innermost" expression [FUN ARGS...] where FUN and ARGS do not contain any other expression (i.e. '[' or ']'). These are directly substitutable. Any number of such expressions may be substituted in any order as determined by the evaluator. Keep it functional, and it's safe! For achieving specific order of substitutions, create a "data dependency" where the dependent calculations wraps the calculation that are needed to be performed before the dependent calculation.

simple string based evaluation

foo => foo
foo [+ 3 4] bar => foo 7 bar
foo [upper bar] fie => foo BAR fie
[[concat up per] fie] = FIE

What is an if-statement, or any choice of execution path, if not just that: a choice of execution path! In this language, we provide an 'if' that will return which named function to invoke on the rest of the data;

[if 0 1 2] => 2
[if 1 1 2] => 1
[if [< 3 4] smaller bigger] => smaller

From this it can be seen that it is NOT a special form or have any specific rules, it only provides a choice of functions to invoke on given arguments.

For example, to implement fac recursively:

[macro fac $n][* $n [[if [<= $n 1] ignore fac] [- $n 1]]][/macro]

> [fac 6]
>>>[fac 6]<<<
>>>[* 6 [[if [<= 6 1] ignore fac] [- 6 1]]]<<<
>>>[* 6 [[if 0 ignore fac] 5]]<<<
>>>[* 6 [fac 5]]<<<
>>>[* 6 [* 5 [[if [<= 5 1] ignore fac] [- 5 1]]]]<<<
>>>[* 6 [* 5 [[if 0 ignore fac] 4]]]<<<
>>>[* 6 [* 5 [fac 4]]]<<<
>>>[* 6 [* 5 [* 4 [[if [<= 4 1] ignore fac] [- 4 1]]]]]<<<
>>>[* 6 [* 5 [* 4 [[if 0 ignore fac] 3]]]]<<<
>>>[* 6 [* 5 [* 4 [fac 3]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [[if [<= 3 1] ignore fac] [- 3 1]]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [[if 0 ignore fac] 2]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [fac 2]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [* 2 [[if [<= 2 1] ignore fac] [- 2 1]]]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [* 2 [[if 0 ignore fac] 1]]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [* 2 [fac 1]]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [* 2 [* 1 [[if [<= 1 1] ignore fac] [- 1 1]]]]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [* 2 [* 1 [[if 1 ignore fac] 0]]]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [* 2 [* 1 [ignore 0]]]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [* 2 [* 1 ]]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 [* 2 1]]]]]<<<
>>>[* 6 [* 5 [* 4 [* 3 2]]]]<<<
>>>[* 6 [* 5 [* 4 6]]]<<<
>>>[* 6 [* 5 24]]<<<
>>>[* 6 120]<<<
>>>720<<<
720

Obviously a more efficient implementation is:

[macro fac $n][* [iota 1 $n]][/macro]

> [fac 6]
>>>[fac 6]<<<
>>>[* [iota 1 6]]<<<
>>>[* 1 2 3 4 5 6 ]<<<
>>>720<<<
720

It can be used and misunderstood easily, the world be dammned!

[macro foo]11 22[/macro]
[macro bar]2 1[/macro]

[if 0 [foo] [bar]] => 22

???

[if 0 [foo] [bar]] =>
[if 0 11 22 [bar]] =>
[if 0 11 22 2 1]] =>
22 !!! second argument returned

How to do IFFFF THEN?

[[if 0 foo bar]] => 2 1
[[if 1 foo bar]] => 11 22

Now, gettin into the gritty, this can be used to implement choice/switch/case-statements!

[macro en-0]zero[/macro]
[macro en-1]one[/macro]
[macro en-2]two[/macro]
[macro en-3]three[/macro]
[macro en-4]four[/macro]
[macro en-5]five[/macro]
[macro en-6]six[/macro]
[macro en-7]seven[/macro]
[macro en-8]eight[/macro]
[macro en-9]nine[/macro]
[macro en-10]ten[/macro]
[macro en-][/macro]

[macro en $digit][en-$digit] [/macro]

[macro english @digits][map en @digits][/macro]

[macro english-rec $digit @digits][en-$digit] [[if [empty @digits] ignore english-rec] @digits][/macro]

help

from command line:

[help]

from web browser

unix> ./jml -w

Goto:

http:localhost:1111/help

super eager evaluation

The interpreter is very simple: it just eagerly evaluates any inner [fun params...] expression where fun and params themselves have no function calls. I.e., the innermost [ ] expressions are replaced successively, the result is achieved by replacing the expression with the body where the formal parameter names have been substituted by the actual values. Parameters are space delimited.

efficiency

Bah... computers are fast! Seriously, we're generating HTML and serving it on the net, so what's fast anyway?

features

  • active messaging
  • reactive, single user space, no address sharing
  • no processes, or tasks, single threaded
  • persistent data/program/functions once "uploaded"
  • simple evaluation mechanism
  • http communication (TODO)

built-in functions

Math

  • % inc dec > < >= <= = !=
  • [+ 1 2 3 4] => 10
  • [* 1 2 3 4] => 24
  • [iota 1 3] => 1 2 3
  • [iota 0 10 2]

Logic

  • [and 1 1 ...] => 1

  • [and 1 0 ...] => 0

  • [not 0] => 1

  • [not 7] => 0

  • [xor 0 0] = [xor 1 1] => 0

  • [xor 0 1] = [xor 1 0] => 1

    val X: empty has is not number alpha

    [X ] 1 0 0 1 0 0 [X 0] 0 1 0 1 1 0 [X 1] 0 1 1 0 1 0 [X a] 0 1 1 0 0 1

Test

  • [if 0 THIS not] => THIS

  • [if X not THAT] => THAT

  • [empty] =>1

  • [empty ...] => 0

  • [empty ] => 1

  • [equal A B] => 0

  • [cmp A B] => 1

  • [cmp B A] => -1

  • [cmp A A] => 0

  • lower upper

  • [length] => 0

  • [length 1 2 3] => 3

  • [length 11 22 33 44] => 4

  • [bytes] => 0

  • [bytes 1 2 3] => 5

  • [bytes 1 2 3 ] => 6

  • [bytes 1 2 3 ] => 7

Lists

  • [ignore X] =>

  • [identity X ...] => X ...

  • [map F a b c ...] => [F a] [F b] [F c] [map F ...]

  • [filter P a b c ...] => [[if [P a] identity ignore] a] ...

  • [filter-do P F a b c ...] => [[if [P a] F ignore] a] ...

  • [nth 2 11 22 33] => 22

  • [first A B] => A

  • [second A B C] => B

  • [third A B C D] => C

  • [rest A B C D] => B C D

Strings

  • [after X abcXzy] => zy

  • [before X abcXzy] = abc

  • [prefix abcdef abc abcd ab] => ab

  • [split a aAaBBaAa] => A BB A

  • [split-do inc a1a22a3a] => 2 23 4

  • [xml name ksajf; sadflk dsaflk <name c='foo'>FISH</name> sdfl sadf asdfdsa] => FISH

  • [substr FIRST LEN abcXzy] get substrings out

  • [substr 0 3 abcXzy] => abc, this is essentially "left"

  • [substr 3 2 abcXzy] => Xz, this is essentially "mid"

  • [substr 4 1 abcXzy] => z

  • [substr -2 -2 abcXzy] => zy get the last N character, this is "right"

  • [concat A B C D ...] => ABCD...

  • [concat A\ B C D ...] => A BCD...

  • [concat [concat a\ b c]] => A BCD...

  • [match a(b*)(cd*)e(.*)f abbbcexxxxxfff] => bbb c xxxxx

  • [match-do F a(b*)(cd*)e(.*)f abbbcexxxxxfff] => [F bbb c xxxxx]

  • [match-do F <(a*)> aaaafishx] => [F aaa] [F aaaa] [F a] [f a]

  • [subst-do F <(a*)> aaaafishx] => aa[F aaa][F aaaa]aa[F a]fish[f a]x

WEB, decode URL

  • [decode foo+bar%2b%25] => foo bar+%
  • [wget URL] => BODY (quoted for safety)
  • [eval/FUN1/Fun2 ...] - see below!

Storage/persistent/database

  • [data firstname Peter] .. [data-firstname] => Peter
  • [datas] =? firstname ...
  • [funcs] => user defined func names
  • [funcs prefix] => user defined func names starting with prefix
  • [funcs start end] => user defined func names in [start, end[
  • [fargs macroname] -> $a $b @foo
  • [fbody macroname] -> foo $a fie $b fum: @foo

Failure

  • [xyz sadfasdf] => [FAIL xyz sadfasdf]
  • [FAIL $id @params] => %(FAIL:xyz sadfasdf) - you can override this!

Content Addressable Network

We also add the capability of (CAN)[https://en.wikipedia.org/wiki/Content_addressable_network].

For now we just implement Content Hashing by using the encrypt function with a fixed non-secret key. It may not qualify as cryptographically secure hashing function, but serves the purpose of a decent hash function, as it's already have it...

TODO: ...

Node Joining

A joining node must:

  • Find a node already in the overlay network
  • Identify a zone that can be split
  • Update the routing tables of nodes neighbouring the newly split node

Node Departing

To handle node departing:

  • Identify a node departing
  • have node's zone merged or taken over by a neighbouring node
  • update the routing tables across the network

heartbeat to neighbours

hotspots

TODO: maybe we're doing (implementing) this???

When searching for NAMED data, we should search for:

[ NAME-HASH    '/' YOUR-ID-HASH '/' ]
[ CHUNK-HASH   '/' YOUR-ID-HASH '/' ]

For example when a file name is hashed for filesystem implementations there may be many hosters/locations storing the same file and registering the same file, in order not to overload a single "bucket" we need to be able to split on a "longer" key so, key for insertions is:

[ NAME-HASH    '/' HOSTER-ID-HASH '/' LIST-HASH ':name' ]  => NAME
[ LIST-HASH    '/' HOSTER-ID-HASH ':file']                 => LIST of (offset, CHUNK)
[ CHUNK-HASH   '/' HOSTER-ID-HASH ':chunk']                => CONTENT

This way the normal splitting would be able to handle hotspots by just splitting the range. When searching you identify yourself and will be routed to the bucket for the same CONTENT-HASH that is closest to your ID.

Example:

file content hash > echo "[content-hash <data...tatatatatat>]" | ./run -q 0A543F0365179C05

> echo "[content-hash <data...other>]" | ./run -q
C0458858B721576B

file name component "StarWarsIV" probably also will have "star" "wars" "iv"... > echo "[content-hash StarWarsIV]" | ./run -q -t A2065D7267A72D3D

star => 015BA7A2250FA4D1
wars => 6181303D2E3EEB6C
iv   => 63AB646145DFFEA9

another file is "star trek"

star => 015BA7A2250FA4D1
trek => EC8DA41B66A78863

this is your node ID:

> uuid
5aaf5bb2-aca3-11e6-b0d5-cb6044163794
> echo "[content-hash 5aaf5bb2-aca3-11e6-b0d5-cb6044163794]" | ./run -q -t
DA623E175D65C3C0

we have 2 more nodes storing this file

64CDE172E66BA52D
FD017067ECF5E177

the second file is stored by you and another person:

4B3722E05881C728

3 nodes have the file thus we will store 3 pointers in the extended key here is the full table

015BA7A2250FA4D1/4B3722E05881C728/C0458858B721576B => star
015BA7A2250FA4D1/64CDE172E66BA52D/0A543F0365179C05 => star
015BA7A2250FA4D1/DA623E175D65C3C0/0A543F0365179C05 => star
015BA7A2250FA4D1/DA623E175D65C3C0/C0458858B721576B => star
015BA7A2250FA4D1/FD017067ECF5E177/0A543F0365179C05 => star

6181303D2E3EEB6C/64CDE172E66BA52D/0A543F0365179C05 => wars
6181303D2E3EEB6C/DA623E175D65C3C0/0A543F0365179C05 => wars
6181303D2E3EEB6C/FD017067ECF5E177/0A543F0365179C05 => wars

A2065D7267A72D3D/64CDE172E66BA52D/0A543F0365179C05 => StarWarsIV
A2065D7267A72D3D/DA623E175D65C3C0/0A543F0365179C05 => StarWarsIV
A2065D7267A72D3D/FD017067ECF5E177/0A543F0365179C05 => StarWarsIV

EC8DA41B66A78863/4B3722E05881C728/C0458858B721576B => trek
EC8DA41B66A78863/DA623E175D65C3C0/C0458858B721576B => trek

example commands

echo "[wget [route-data [content-hash Hello. This is a message!]]/id]" | ./run -q -t

This hashes by content, finds the route, connects to that server, retrieves /id URL that should contain its hash.

We need a distributed filesystem

see above?

Two variants

  • CA, Content Addressable, hash the content, store on the node as owner, and "k nearest".
  • by URL name, like PAST: hash by URL to find (date,size,CA-hashes)

Note on quoting

Since everything works by substitution (close to lambda calculus?), the need for quoting is low. This is normally called interpolation in languages as Perl. In JML it's a little different as the interpolated string is continously interpolated by substitutions of [fun ...] "calls". However, as it's uses '[', ']', and ' ' as significant these now instead need to be quoted. LOL. However, for the domain of email. This is "convenient".

This is how to quote these characters

  • A\ B is interpreted as one parameter in calling, see concat above
  • [+ 3 4] will print [+ 3 4] and not 7

Safety, "SQL Injection"

In order to not allow injection, certain "web" characters should be quoted on "input" from the web or external sources. Examples include: < > [ ] & ' "

eval/fun1/fun2/fun3...

Having an eval is flexible, however, a big security risk. We take the middle-ground and provide a "sandboxed" eval. When eval is invoked it also requires an enumeration of all functions that are allowed to be called. Essentially this defines an API. For example to define a calculator with only plus minus times divide you specify [eval/plus/minus/times/divide ...] Eval will change then change each occurance of {FUN...} to [FUN...] if fun is listed. If {} doesn't balance, empty string is returned, same if unlisted FUN is mentioned. This doesn't limit further eval/substituations.

This, for example, can be used to implement a forward request in CHORD/DHT by having the server return updates as well as a new request in case the route is wrong. If the routing is right the contacted server would return it's own ID. Otherwise it returns a "textual-continuation" (program with data filled in), which coincidentially is exactly what a jml-program is!

[route-resolve $HASH]

If this doesn't resolve to the server you're at, it'll wget call that server and it will either confirm, or return "forwarding instructions". Essentially, some updates (route-add) and then a new route-resolve that depends on those updates.

{route-resolve $HASH {route-add 0375F9AB200504E9 2016-... http:...} {route-add DB348B3005A37278 2016-... http:...}}

These are performed at/by the originating server, which will use:

[eval/route-resolve/route-add ...]

to evaluate, if it again doesn't resolve locally, we'll get another forward and the new remote server will conform that it is the receipient by returning it's ID:

$HOST_ID

Unicode

TODO: Haha, come again? Don't you know the world consists of bits and bytes?

Seriously, the web is multilingular, and I travel in china, use swedish so UTF-8 is a reasonable requirement.

UTF-8:

"And ASCII bytes do not occur when encoding non-ASCII code points into UTF-8, making UTF-8 safe to use within most programming and document languages that interpret certain ASCII characters in a special way, e.g. as end of string."

  • [encrypt FOOBAR] => {39CE0CD92EEBACC8}
  • [decrypt {39CE0CD92EEBACC8}] => FOOBAR
  • [encrypt-eval {+ 3 4}] => {D9403DC570A74AF1}
  • [decrypt {D9403DC570A74AF1}] => {+ 3 4}
  • [decrypt-eval {D9403DC570A74AF1}] => [+ 3 4] => 7

using custom keys

The default key is "1234123412341234", maximum lenght is 16, ascii, no "/" or " " character allowed. The key is part of the "function" name (funny hack) thus the name to use is [encrypt/MYSECURITYKEY data to encrypt], similarly for decrypt/MYSECURITYKEY, encrypt-eval/decrypt-eval...

Note on "security", it's just XXTEA which can only provide nominal security in access. They keys aren't protected and if one has access to the physical device would be able to extract the key. However, each instance should have it's own key and the person communicating with it need it too. This means; It's protected against middle-man attack. Each unikernel/device should have it's own key. It may be possible to use the key to only allow the owner of that key to modify and run any code. Others would only be allowed to interact using the public defined macro functions, like [macro /foo]...

Encrypted data becomes HEX coded, to keep it ascii, thus it will at use at least the double amount of bytes.

TODO: enable setting/changing keys

Termination

Currently, if you loop forever by recursion there is no limit. One could add a max-substitution count, or time that would terminate the current running request.

Alternative Universe Inspired Readings

Readings about x86 style OSes

Urbit summary (and features I'd like have?)

urbit intro by third party

  • decentralized computing platform
  • clean-slate OS
  • personal server
  • persistent virtual computer
  • you own it, trust and control
  • "Urbit is perhaps how you'd do computing in a post-singularity world, where computational speed and bandwidth are infinite, and what's valuable is security, trust, creativity, and collaboration. It's essentially a combination of a programming language, OS, virtual machine, social network, and digital identity platform."
  • UDP
  • reputation based social network (?)
  • event logging

jml's People

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