serval-dna/doc/Servald-REST-API.md

Serval DNA REST API
===================
[Serval Project][], September 2015

Introduction
------------

The [Serval DNA][] daemon that runs on every node in a Serval Mesh network
gives applications access to the network through two main [API][]s:

*  the [MDP API][MDP] and [MSP API][MSP] provide "traditional" packet and
   stream transport, allowing applications to send and receive Serval network
   packets to and from nearby nodes with latencies of up to several seconds;

*  the [HTTP REST][] API provides applications with access to the following
   Serval services:
   -  [Keyring][] -- local identity management
   -  [Rhizome][] -- store-and-forward (high latency) content distribution
   -  [MeshMS][] -- secure one-to-one messaging using Rhizome as transport

This document describes the second of these, the [HTTP REST][] API.

### Protocol and port

The Serval DNA [HTTP REST][] API is an [HTTP 1.0][] server that only accepts
requests on the loopback interface (IPv4 address 127.0.0.1), TCP port 4110.  It
rejects requests that do not originate on the local host, by replying
[403](#forbidden).

### Security

The REST API is a clear-text interface; requests and responses are *not*
encrypted.  HTTP REST is not carried over any physical network link so it is
not exposed to remote eavesdroppers.  That means the only threat comes from
local processes.

Linux prevents normal processes from accessing the traffic on local sockets
between other processes, so to attack Serval DNA and its clients, a local
process on the local host would have to gain super-user privilege (eg, through
a privilege escalation vulnerability), which would give it many avenues for
attacking Serval DNA and its clients.  In this situation, encrypting
client-server communications would offer no protection whatsoever.

### Authentication

Clients of the HTTP REST API must authenticate themselves using [Basic
Authentication][].  This narrows the window for opportunistic attacks on the
HTTP port by malicious applications that scan for open local ports to exploit.
Any process wishing to use the REST API must supply valid authentication
credentials (name/password), or will receive a [401 Unauthorized](#401-unauthorized)
response.

Client applications obtain their REST API credentials via a back channel
specific to their particular platform.  This delegates the exercise of handing
out credentials to the application layer, where users can (usually) exercise
their own discretion.  For example, on Android, a client app sends an
[Intent][] to the [Serval Mesh][] app requesting a Serval REST credential, and
will receive a reply only if it possesses the right Android [Permission][].
When users install or run the client app, Android informs them that the app
requests the "Serval Network" permission, and users may allow or deny it.

As a fall-back mechanism, created primarily to facilitate testing, HTTP REST
API credentials can be [configured][] using configuration options of the form:

    api.restful.users.USERNAME.password=PASSWORD

PASSWORD is a cleartext secret, so the Serval DNA configuration file must be
protected from unauthorised access or modification by other apps.  That makes
this mechanism unsuitable for general use.

### Request

An HTTP REST request is a normal [HTTP 1.0][] [GET](#get) or [POST](#post):

#### GET

A **GET** request consists of an initial "GET" line containing the *path* and
*HTTP version*, followed by zero or more header lines, followed by a blank
line.  As usual for HTTP, all lines are terminated by an ASCII CR-LF sequence.

For example:

    GET /restful/keyring/identities.json?pin=1234 HTTP/1.0
    Authorization: Basic aGFycnk6cG90dGVy
    Accept: */*
    

#### POST

A **POST** request is the same as a GET request except that the first word
of the first line is "POST", the blank line is followed by a request body,
and the following request headers are mandatory:
*   [Content-Length](#request-content-length)
*   [Content-Type](#request-content-type)

#### Request Content-Length

In a request, the **Content-Length** header gives the exact number of bytes
(octets) in the request's body, which must be correct.  Serval DNA will not
process a request until it receives Content-Length bytes, so if Content-Length
is too large, the request will suspend and eventually time out.  Serval DNA
will ignore any bytes received after it has read Content-Length bytes, so if
Content-Length is too small, the request body will be malformed.

#### Request Content-Type

In a request, the **Content-Type** header gives the [Internet Media Type][] of
the body.  Serval DNA currently supports the following media types in requests:

*   **multipart/form-data; boundary=** is used to send large parameters
    in POST requests

*   **text/plain; charset=utf-8** is used for [MeshMS][] message form
    parts

*   **rhizome/manifest; format=text+binarysig** is used for [Rhizome][]
    manifest form parts

#### Request Range

[HTTP 1.1 Range][] retrieval is partially supported.  In a request, the
**Range** header gives the start and end, in byte offsets, of the resource to
be returned.  The server may respond with exactly the range requested, in which
case the response status code will be [206](#partial-content), or it may ignore
the Range header and respond with the entire requested resource.

For example, the following header asks that the server omit the first 64 bytes
and send only the next 64 bytes (note that ranges are inclusive of their end
byte number):

    Range: bytes=64-127

The [specification][HTTP 1.1 Range] allows for more than one start-end range to
be supplied, separated by commas, however not all REST API operations support
multi ranges.  If a multi-range header is used in such a request, then the
response may be the entire content or [501 Not Implemented](#not-implemented).

[HTTP 1.1 Range]: http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35

### Responses

An HTTP REST response is a normal [HTTP 1.0][] response consisting of a header
block, a blank line, and an optional body, for example: As usual, all lines are
terminated by an ASCII CR-LF sequence.  For example:

    HTTP/1.0 200 OK
    Content-Type: application/json
    Content-Length: 78

    {
     "http_status_code": 200,
     "http_status_message": "OK"
    }

The lingua franca of the HTTP REST API is [JSON][] in [UTF-8][] encoding.  All
Serval DNA HTTP REST responses have a Content-Type of **application/json**
unless otherwise documented.

Some responses contain non-standard HTTP headers as part of the result they
return to the client; for example, [Rhizome response headers](#rhizome-response-headers).

### Response status code

The HTTP REST API response uses the [HTTP status code][] to indicate the
outcome of the request as follows:

[HTTP status code]: http://www.w3.org/Protocols/HTTP/1.0/spec.html#Status-Codes

#### 200 OK

The operation was successful and no new entity was created.  Most requests
return this code to indicate success.  Requests that create a new entity only
return this code if the entity already existed, meaning that the creation was
not performed but the request can be considered a success since the desired
outcome was achieved: namely, the existence of the entity.  (If the entity was
created, then these requests return [201 Created](#created) instead.)

(Serval APIs are all [idempotent][] with respect to creation: creating the same
entity twice yields the same state as creating it once.  This is an important
property for a purely distributed network that has no central arbiter to
enforce sequencing of operations.)

#### 201 Created

The operation was successful and the entity was created.  This code is only
returned by requests that create new entities, in the case that the entity did
not exist beforehand and has been created successfully.

#### 202 Accepted

The operation was successful but the entity was not created.  This code is only
returned by requests that create new entities, in the case that the request was
valid but the entity was not created because other existing entities take
precedence.  For example, the [Rhizome REST API](#rhizome-rest-api) returns
this code when inserting a bundle to a full Rhizome store if the new bundle's
rank falls below all other bundles, so the new bundle itself would be evicted
to make room.

#### 206 Partial Content

The operation was successful and the response contains part of the requested
content.  This code is only returned by requests that fetch an entity (the
fetched entity forms the body of the response) if the request supplied a
[Range](#request-range) header that specified less than the entire entity.

#### 400 Bad Request

The HTTP request was malformed, and should not be repeated without
modifications.  This could be for several reasons:
- invalid syntax in the request header block
- a `POST` request MIME part is missing, duplicated or out of order
- a `POST` request was given an unsupported MIME part
- a `POST` request MIME part has missing or malformed content

#### 401 Unauthorized

The request did not supply an "Authorization" header with a recognised
credential.  This response contains a "WWW-Authenticate" header that describes
the missing credential:

    HTTP/1.0 401 Unauthorized
    Content-Type: application/json
    Content-Length: 88
    WWW-Authenticate: Basic "Serval RESTful API"

    {
     "http_status_code": 401
     "http_status_message": "Unauthorized"
    }

#### 403 Forbidden

The request failed because the server does not accept requests from the
originating host.

#### 404 Not Found

The request failed because the [HTTP request URI][] does not exist.  This could
be for several reasons:
- the request specified an incorrect path (typographic mistake)
- the path is unavailable because the API in question is unavailable (eg, the
  [Rhizome REST API](#rhizome-rest-api)) is currently [configured][] as
  disabled
- the path contains a reference to an entity (eg, [SID][], [BID][]) that does
  not exist

[HTTP request URI]: http://www.w3.org/Protocols/HTTP/1.0/spec.html#Request-URI

#### 405 Method Not Allowed

The request failed because the [HTTP request method][] is not supported for the
given path.  Usually this means that a [GET](#get) request was attempted on a
path that only supports [POST](#post), or vice versa.

[HTTP request method]: http://www.w3.org/Protocols/HTTP/1.0/spec.html#Method

#### 411 Length Required

A `POST` request did not supply a [Content-Length](#request-content-length)
header.

#### 414 Request-URI Too Long

The request failed because the [HTTP request URI][] was too long.  The server
persists the path and a few other pieces of the request in a fixed size request
buffer, and this response is triggered if the collective size of these does not
leave enough buffer for receiving the remainder of the request.

#### 415 Unsupported Media Type

A `POST` request failed because of an unsupported content type, which could be
for several reasons:
- the request's [Content-Type](#request-content-type) header specified an
  unsupported media type
- a MIME part Content-Disposition was not “form-data”
- a MIME part Content-Type was unsupported
- a MIME part Content-Type specified an unsupported charset

#### 416 Requested Range Not Satisfiable

The [Range](#request-range) header specified a range whose start position falls
outside the size of the requested entity.

#### 419 Authentication Timeout

The request failed because the server does not possess and cannot derive the
necessary cryptographic secret or credential.  For example, updating a Rhizome
bundle without providing the bundle secret.  This code is not part of the HTTP
standard.

#### 422 Unprocessable Entity

A `POST` request supplied data that was inconsistent or violates semantic
constraints, so cannot be processed.  For example, the [Rhizome
insert](#post-restful-rhizome-insert) operation responds with 422 if the
manifest *filesize* and *filehash* fields do not match the supplied payload.

#### 423 Locked

The request cannot be performed because a necessary resource is busy for
reasons outside the control of the requester and server.

This code is returned by Rhizome requests if the Rhizome store database is
currently locked by another process.  The architecture of [Serval DNA][] is
being improved to prevent any process other than the Serval DNA daemon itself
from directly accessing the Rhizome database.  Once these improvements are
done, this code should no longer occur except during unusual testing and
development situations.

#### 429 Too Many Requests

The request cannot be performed because a necessary resource is temporarily
unavailable due to a high volume of concurrent requests.

The original use of this code was for Rhizome operations if the server's
manifest table ran out of free manifests, which would only happen if there were
many concurrent Rhizome requests holding manifest structures open in server
memory.

This code may also be used to indicate temporary exhaustion of other finite
resources.  For example, if [Serval DNA][] is ever limited to service only a
few HTTP requests at a time, then this code will be returned to new requests
that would exceed the limit.

#### 431 Request Header Fields Too Large

The request header block was too long.

Initial implementations of [Serval DNA][] allocated approximately 8 KiB of
buffer memory for each [request](#request), and the HTTP server read each
header line entirely into that buffer before parsing it.  If a single header
exceeded the size of this buffer, then the 431 response was returned.

#### 500 Internal Server Error

The request failed because of an internal error in [Serval DNA][], not an error
in the request itself.  This could be for several reasons:
- software defect (bug)
- unavailable system resource (eg, memory, disk space)
- corrupted environment (eg, bad configuration, database inconsistency)

Internal errors of this kind may persist or may resolve if the request is
re-tried, but in general they will persist because the cause is not transient.
Temporary failures that can be resolved by re-trying the request are generally
indicated by other status codes, such as [423](#locked).

#### 501 Not Implemented

The requested operation is valid but not yet implemented.  This is used for the
following cases:

- a request [Range](#request-range) header specifies a multi range

#### Cross-Origin Resource Sharing (CORS)

To support client-side JavaScript applications, Serval DNA has a limited
implementation of [Cross-Origin Resource Sharing][CORS].  If a request contains
an **Origin** header with either “null” or a single URI with scheme “http” or
“https” or “file”, hostname “localhost” or “127.0.0.1” (or empty in the case of
a “file” scheme), and optionally any port number, then the response will
contain three **Access-Control** headers granting permission for other pages on
the same site to access resources in the returned response.

For example, given the request:

    GET /restful/keyring/identities.json HTTP/1.0
    Origin: http://localhost:8080/
    ...
    
Serval DNA will respond:

    HTTP/1.0 200 OK
    Access-Control-Allow-Origin: http://localhost:8080
    Access-Control-Allow-Methods: GET, POST, OPTIONS
    Access-Control-Allow-Headers: Authorization
    ...

[CORS]: http://www.w3.org/TR/cors/

#### JSON result

All responses that convey no special content return the following *JSON result*
object:

    {
     "http_status_code": ...,
     "http_status_message": "..."
    }

The `http_status_code` field is an integer equal to the [status
code](#response-status-code) that follows the `HTTP/1.0` token in the first
line of the response.

The `http_status_message` field is usually the same as the *reason phrase* text
that follows the code in the first line of the HTTP response.  This reason
phrase may be a [standard phrase][status code], or it may be more explanatory;
for example, some *404* responses from Rhizome have phrases like, “Bundle not
found”, “Payload not found”, etc.

Some responses augment the *JSON result* object with extra fields; for example,
[Rhizome JSON result](#rhizome-json-result).

### JSON table

Many HTTP REST responses that return a list of regular objects (eg, [GET
/restful/rhizome/bundlelist.json](#get-restfulrhizomebundlelistjson)) use the
following *JSON table* format:

    {
        "header":["fieldname1","fieldname2","fieldname3", ... ],
        "rows":[
            [field1, field2, field3, ... ],
            [field1, field2, field3, ... ],
            ...
        ]
    }

The JSON table format is more compact than the most straightforward JSON
representation, an array of JSON objects, which has the overhead of redundantly
repeating all field labels in every single object:

    [
        {
            "fieldname1: field1,
            "fieldname2: field2,
            "fieldname3: field3,
            ...
        },
        {
            "fieldname1: field1,
            "fieldname2: field2,
            "fieldname3: field3,
            ...
        },
        ...
    ]



A JSON table can easily be transformed into its equivalent array of JSON
objects.  The [test scripts](./testdefs_json.sh) use the following [jq(1)][]
expression to perform the transformation:

    [
        .header as $header |
        .rows as $rows |
        $rows | keys | .[] as $index |
        [ $rows[$index] as $d | $d | keys | .[] as $i | {key:$header[$i], value:$d[$i]} ] |
        from_entries |
        .["__index"] = $index
    ]

Keyring REST API
----------------

The Keyring REST API allows client applications to query, unlock, lock, create,
and modify Serval Identities in the keyring.

### Identity unlocking

All Keyring API requests can supply a password using the optional **pin**
parameter, which unlocks all keyring identities protected by that password
prior to performing the request.  Serval DNA caches every password it receives
until the password is revoked using the *lock* request, so once an identity is
unlocked, it remains visible until explicitly locked.

Identities with an empty password are permanently unlocked, and cannot be
locked.

### GET /restful/keyring/identities.json

Returns a list of all currently unlocked identities, in [JSON
table](#json-table) format.  The table columns are:

*   **sid**: the [SID][] of the identity, a string of 64 hex digits
*   **did**: the optional [DID][] (telephone number) of the identity, either
    *null* or a string of five or more digits from the set `123456789#0*`
*   **name**: the optional name of the identity, either *null* or a non-empty
    string of [UTF-8] characters

### GET /restful/keyring/add

Creates a new identity with a random [SID][].  If the **pin** parameter is
supplied, then the new identity will be protected by that password, and the
password will be cached by Serval DNA so that the new identity is unlocked.

### GET /restful/keyring/SID/set

Sets the [DID][] and/or name of the unlocked identity that has the given
[SID][].  The following parameters are recognised:

*   **did**: sets the DID (phone number); must be a string of five or more
    digits from the set `123456789#0*`
*   **name**: sets the name; must be non-empty

If there is no unlocked identity with the given SID, this request returns *404
Not Found*.

Rhizome REST API
----------------

A Rhizome *bundle* consists of a single *manifest* and an optional *payload*.

TBC

### Rhizome response headers

All Rhizome requests that fetch or insert a single bundle, whatever the
outcome, contain the following HTTP headers in the response:

    Serval-Rhizome-Result-Bundle-Status-Code: -1|0|1|2|3|4|5|6|7
    Serval-Rhizome-Result-Bundle-Status-Message: <text>
    Serval-Rhizome-Result-Payload-Status-Code: -1|0|1|2|3|4|5|6|7|8
    Serval-Rhizome-Result-Payload-Status-Message: <text>

*  the `Serval-Rhizome-Result-Bundle-Status-Code` header is the integer [bundle
   status code](#bundle-status-code)
*  the `Serval-Rhizome-Result-Bundle-Status-Message` header is the string
   [bundle status message](#bundle-status-message)
*  the `Serval-Rhizome-Result-Payload-Status-Code` header is the integer
   [payload status code](#payload-status-code)
*  the `Serval-Rhizome-Result-Payload-Status-Message` header is the string
   [payload status message](#payload-status-message)

### Rhizome response bundle headers

All Rhizome requests that *successfully* fetch or insert a single bundle
contain the following HTTP headers in the response, which convey the core
manifest fields:

    Serval-Rhizome-Bundle-Id: <hex64bid>
    Serval-Rhizome-Bundle-Version: <integer>
    Serval-Rhizome-Bundle-Filesize: <integer>

If *filesize* is not zero, then the following HTTP header is present:

    Serval-Rhizome-Bundle-Filehash: <hex128>

If the bundle is a *journal*, then the following HTTP header is present:

    Serval-Rhizome-Bundle-Tail: <integer>

In addition, none, some or all of the following HTTP headers may be present, to
convey optional fields that are present in the bundle's manifest:

    Serval-Rhizome-Bundle-Sender: <hex64sid>
    Serval-Rhizome-Bundle-Recipient: <hex64sid>
    Serval-Rhizome-Bundle-BK: <hex64>
    Serval-Rhizome-Bundle-Crypt: 0 or 1
    Serval-Rhizome-Bundle-Service: <token>
    Serval-Rhizome-Bundle-Name: <quotedstring>
    Serval-Rhizome-Bundle-Date: <integer>

All single-bundle operations, unless otherwise specified, attempt to deduce the
bundle's author by finding whether the manifest's signature could be re-created
using a Rhizome Secret from a currently unlocked identity in the keyring.  If
the manifest `sender` field is present or the author has been cached in the
Rhizome database, then only that identity is tried, otherwise every single
identity in the keyring is tested.  If a signing identity is found, then the
following HTTP header is present:

    Serval-Rhizome-Bundle-Author: <hex64sid>

(Note that there is no manifest “author” field, and the “sender” field is
optional, in order to support anonymous bundles.  This is why the author must
be deduced in this fashion.  Serval DNA caches the authors it discovers, to
avoid redundant re-testing of all keyring identities, but cached authors are
not automatically treated as verified when read from the Rhizome database,
because the database can be altered by external means.)

If the bundle's secret is known, either because it was supplied in the request
or was deduced from the manifest's Bundle Key (BK) field and the author's
Rhizome Secret (RS), then the following HTTP header is present:

    Serval-Rhizome-Bundle-Secret: <hex64>

The following HTTP headers might be present at the sole discretion of the
server, but they are not guaranteed, and future upgrades of [Serval DNA][] may
remove them.  They reveal internal details of the storage of the bundle:

    Serval-Rhizome-Bundle-Rowid: <integer>
    Serval-Rhizome-Bundle-Inserttime: <integer>

### Rhizome JSON result

All Rhizome requests to fetch or insert a single bundle that do not produce a
special response content for the outcome, return the following augmented [JSON
result](#json-result) object as the HTTP response content:

    {
     "http_status_code": ...,
     "http_status_message": "...",
     "rhizome_bundle_status_code": ...,
     "rhizome_bundle_status_message": "...",
     "rhizome_payload_status_code": ...,
     "rhizome_payload_status_message": "..."
    }

*  the `rhizome_bundle_status_code` field is the integer [bundle status code](#bundle-status-code)
*  the `rhizome_bundle_status_message` field is the string [bundle status message](#bundle-status-message)
*  the `rhizome_payload_status_code` field is the integer [payload status code](#payload-status-code)
*  the `rhizome_payload_status_message` field is the string [payload status message](#payload-status-message)

#### Bundle status code

All Rhizome operations that involve fetching and/or inserting a single manifest
into the Rhizome store return a *bundle status code*, which describes the
outcome of the operation.  Some codes have different meanings in the context of
a fetch or an insertion, and some codes can only be produced by insertions.
The bundle status code determines the [HTTP response code](#response-status-code).

| code | HTTP | meaning                                                                         |
|:----:|:----:|:------------------------------------------------------------------------------- |
|  -1  |  500 | internal error                                                                  |
|   0  |  201 | "new"; (fetch) bundle not found; (insert) bundle added to store                 |
|   1  |  200 | "same"; (fetch) bundle found; (insert) bundle already in store                  |
|   2  |  200 | "duplicate"; (insert only) duplicate bundle already in store                    |
|   3  |  202 | "old"; (insert only) newer version of bundle already in store                   |
|   4  |  422 | "invalid"; (insert only) manifest is invalid                                    |
|   5  |  419 | "fake"; (insert only) manifest signature is invalid                             |
|   6  |  422 | "inconsistent"; (insert only) manifest filesize/filehash does not match payload |
|   7  |  202 | "no room"; (insert only) doesn't fit; store may contain more important bundles  |
|   8  |  419 | "readonly"; (insert only) cannot modify manifest because secret is unknown      |
|   9  |  423 | "busy"; Rhizome store database is currently busy (re-try)                       |

#### Bundle status message

The *bundle status message* is a short English text that explains the meaning
of its accompanying *bundle status code*, to assist with diagnosis.  The
message for a code may differ across requests and may change when [Serval
DNA][] is upgraded, so it cannot be relied upon as a means to programmatically
detect the outcome of an operation.

#### Payload status code

All Rhizome operations that involve fetching and/or inserting a single payload
into the Rhizome store return a *payload status code*, which describes the
outcome of the payload operation, and elaborates on the the reason for the
accompanying *bundle status code*.  Some codes have different meanings in the
context of a fetch or an insertion, and some codes can only be produced by
insertions.  The payload status code overrides the [HTTP response
code](#response-status-code) derived from the [bundle status
code](#bundle-status-code) if it is numerically higher.

| code | HTTP | meaning                                                               |
|:----:|:----:|:--------------------------------------------------------------------- |
|  -1  |  500 | internal error                                                        |
|   0  |  201 | empty payload (zero length)                                           |
|   1  |  201 | (fetch) payload not found; (insert) payload added to store            |
|   2  |  200 | (fetch) payload found; (insert) payload already in store              |
|   3  |  422 | payload size does not match manifest *filesize* field                 |
|   4  |  422 | payload hash does not match manifest *filehash* field                 |
|   5  |  419 | payload key unknown: (fetch) cannot decrypt; (insert) cannot encrypt  |
|   6  |  202 | (insert only) payload is too big to fit in store                      |
|   7  |  202 | (insert only) payload evicted; other payloads are ranked higher       |

#### Payload status message

The *payload status message* is short English text that explains the meaning of
its accompanying *payload status code*, to assist diagnosis.  The message for a
code may differ across requests and may change when [Serval DNA][] is upgraded,
so it cannot be relied upon as a means to programmatically detect the outcome
of an operation.

### GET /restful/rhizome/bundlelist.json

Fetches a list of all bundles currently in [Serval DNA][]'s Rhizome store, in
order of descending insertion time starting with the most recently inserted.
The list is returned in the body of the [response](#response) in [JSON
table](#json-table) format with the following columns:

*  `.token` - either *null* or a string value that can be used as the token in
   a [newsince](#get-restful-rhizome-newsince-token-bundlelist-json) request.

*  `_id` - the Rhizome database row identifier; a unique integer per bundle
   with no guarantees of sequence or re-use after deletion.

*  `service` - the string value of the manifest's *service* field, or *null* if
   the manifest has no *service* field.

*  `id` - the [Bundle ID][BID]; a string containing 64 hexadecimal digits.

*  `version` - the bundle version; a positive integer with a maximum value of
   2^64 − 1.

*  `date` - the bundle publication time; an integral [Unix time][] or *null* if
   the manifest has no *date* field.  This field is set by the bundle's creator
   and could have any value, due either to inaccuracies in the system clock
   used to make the time stamp, or deliberate falsification.  This field can
   have values up to 2^64 − 1, so it is immune to the [Y2038 problem][].

*  `.inserttime` - the time that the bundle was inserted into the local Rhizome
   store.  This field is created using the local system clock, so comparisons
   with the `date` field cannot be relied upon as having any meaning.

*  `.author` - the [SID][] of the local (unlocked) identity that created the
   bundle; either a string containing 64 hexadecimal digits, or *null* if the
   author cannot be deduced (the manifest lacks a *BK* field) or is not an
   [unlocked identity](#get-restful-keyring-identities-json).  In the case of
   *null*, the `.fromhere` field will be 0 (“not authored here”).  In the case
   of a SID, the `.fromhere` indicates whether authorship was absent, likely or
   certain.

*  `.fromhere` - an integer flag that indicates whether the bundle was authored
   on the local device:

   *  `0` (“absent”) means the bundle was not authored by any identity on this
      device, which could be because either:
      *  the author's identity is not unlocked in the local keyring, or
      *  the author's identity is in the local keyring but does not verify
         cryptographically as the author.

   *  `1` (“likely”) means the author whose [SID][] is given in the `.author`
      field is present in the local keyring but authorship (the manifest's
      signature) has not been cryptographically verified, so attempting to
      update this bundle may yet fail.  This is the usual value for most
      bundles in a list because cryptographic verification is not performed
      while listing bundles, since it is slow and costly in CPU and battery.

   *  `2` (“certain”) means the author whose [SID][] is given in the `.author`
      field is present in the local keyring and has been cryptographically
      verified as the true author of the bundle, so it is possible to update
      this bundle.  This value will usually only be returned for
      locally-authored bundles that have recently been examined individually
      (eg, [GET /restful/rhizome/BID.rhm](#get-restful-rhizome-bid-rhm)), if
      Serval DNA has cached the result of the verification in memory.

*  `filesize` - the number of bytes in the bundle's payload; an integer zero or
   positive with a maximum value of 2^64 − 1.

*  `filehash` - if the bundle has a non-empty payload, then the [SHA-512][]
   hash of the payload content; a string containing 128 hexadecimal digits,
   otherwise *null* if the payload is empty (*filesize* = 0).

*  `sender` - the [SID][] of the bundle's sender; either a string containing 64
   hexadecimal digits, or *null* if the manifest has no *sender* field.

*  `recipient` - the [SID][] of the bundle's recipient; either a string
   containing 64 hexadecimal digits, or *null* if the manifest has no
   *recipient* field.

*  `name` - the string value of the manifest's *name* field, or *null* if the
   manifest has no *name* field.

### GET /restful/rhizome/newsince/TOKEN/bundlelist.json

TBC

### GET /restful/rhizome/BID.rhm

Fetches the manifest for the bundle whose id is `BID` (64 hex digits), eg:

    /restful/rhizome/1702BD647D614DB72C36BD634B6870CA31040C2EEC5069AEC0C0841D0CC671BE.rhm

If the **manifest is found** in the local Rhizome store, then the response will
be *200 OK* and:
*  the [bundle status code](#bundle-status-code) will be 1
*  the [payload status code](#payload-status-code), if present in the response,
   is not relevant, so must be ignored
*  the [Rhizome response bundle headers](#rhizome-response-bundle-headers) give
   information about the found bundle, some of which is duplicated from the
   manifest
*  the response's Content-Type is **rhizome/manifest; format=text+binarysig**
*  the response's Content-Length is the size, in bytes, of the manifest with
   its binary signature appended
*  the response's content is the Rhizome manifest in text format followed by a
   nul (0) byte followed by the manifest's binary signature

If the **manifest is not found** in the local Rhizome store, then the response
will be *404 Bundle not found* and:
*  the [bundle status code](#bundle-status-code) will be 0
*  the [payload status code](#payload-status-code), if present in the response,
   is not relevant, so must be ignored
*  the [Rhizome response bundle headers](#rhizome-response-bundle-headers) are
   absent from the response
*  the response's content is the [Rhizome JSON result](#rhizome-json-result)
   object

### GET /restful/rhizome/BID/raw.bin

Fetches the "raw" (encrypted) payload for the bundle whose id is `BID` (64 hex
digits), eg:

    /restful/rhizome/1702BD647D614DB72C36BD634B6870CA31040C2EEC5069AEC0C0841D0CC671BE/raw.bin

If the **manifest and the payload are both found** in the local Rhizome store,
then the response will be *200 OK* and:
*  the [bundle status code](#bundle-status-code) will be 1
*  the [payload status code](#payload-status-code) will be 0 if the payload has
   zero length, otherwise 2
*  the [Rhizome response bundle headers](#rhizome-response-bundle-headers) give
   information about the found bundle, some of which is duplicated from the
   manifest
*  the response's Content-Type is **application/octet-stream**
*  the response's Content-Length is the size, in bytes, of the raw payload
*  the response's content is the bundle's payload exactly as stored in Rhizome;
   if the payload is encrypted (the manifest's `crypt` field is 1) then the
   payload is not decrypted

If the **manifest is not found** in the local Rhizome store, then the response
will be *404 Bundle not found* and:
*  the [bundle status code](#bundle-status-code) will be 0
*  the [payload status code](#payload-status-code), if present in the response,
   is not relevant, so must be ignored
*  the [Rhizome response bundle headers](#rhizome-response-bundle-headers) are
   absent from the response
*  the response's content is the [Rhizome JSON result](#rhizome-json-result)
   object

If the **manifest is found** in the local Rhizome store but the **payload is
not found**, then the response will be *404 Payload not found* and:
*  the [bundle status code](#bundle-status-code) will be 1
*  the [payload status code](#payload-status-code) will be 1
*  the [Rhizome response bundle headers](#rhizome-response-bundle-headers) give
   information about the found manifest
*  the response's content is the [Rhizome JSON result](#rhizome-json-result)
   object

### GET /restful/rhizome/BID/decrypted.bin

Fetches the decrypted payload for the bundle whose id is `BID` (64 hex digits),
eg:

    /restful/rhizome/1702BD647D614DB72C36BD634B6870CA31040C2EEC5069AEC0C0841D0CC671BE/decrypted.bin

The responses are identical to those for [GET /restful/rhizome/BID/raw.bin](get-restful-rhizome-bid-raw-bin),
with the following additional case:

If the **manifest and payload are both found** and the payload is **encrypted**
(the manifest's `crypt` field is 1), but the **payload secret is not known**,
then:
*  the [bundle status code](#bundle-status-code) will be 0
*  the [payload status code](#payload-status-code) will be 5
*  the [Rhizome response bundle headers](#rhizome-response-bundle-headers) give
   information about the found manifest
*  the response's content is the [Rhizome JSON result](#rhizome-json-result)
   object

For a bundle that has a *sender* and a *recipient*, the payload secret is
determined as follows:
*  if the recipient's identity is found (unlocked) in the keyring, then the
   secret is derived from the recipient's private key; otherwise
*  if the recipient's identity is not found in the keyring (locked or missing)
   but the sender's identity is found (unlocked) in the keyring, then the
   secret is derived from the sender's private key; otherwise
*  neither identity is found in the keyring (both are locked or missing), so
   the payload secret is unknown.

For all other bundles, the payload secret is derived from the Bundle Secret.
*  if the correct Bundle Secret was supplied in the request then the payload
   secret is derived from it directly; otherwise
*  if the manifest contains a `BK` field, and the bundle's author can be
   deduced from the manifest's signature and the author's identity is found
   (unlocked) in the keyring, then the Bundle Secret is derived from the BK
   field and the author's Rhizome Secret, then the payload secret is derived
   from that; otherwise
*  the Bundle Secret is unknown, so the payload secret is unknown.

### POST /restful/rhizome/insert

TBC

MeshMS REST API
---------------

TBC

### GET /restful/meshms/RECIPIENTSID/conversationlist.json

TBC

### GET /restful/meshms/SENDERSID/RECIPIENTSID/messagelist.json

TBC

### GET /restful/meshms/SENDERSID/RECIPIENTSID/newsince/TOKEN/messagelist.json

TBC

### POST /restful/meshms/SENDERSID/RECIPIENTSID/sendmessage

TBC


-----
**Copyright 2015 Serval Project Inc.**  
![CC-BY-4.0](./cc-by-4.0.png)
Available under the [Creative Commons Attribution 4.0 International licence][CC BY 4.0].


[Serval Project]: http://www.servalproject.org/
[CC BY 4.0]: ../LICENSE-DOCUMENTATION.md
[Serval DNA]: ../README.md
[Serval Mesh]: http://developer.servalproject.org/dokuwiki/doku.php?id=content:servalmesh:development
[Keyring]: http://developer.servalproject.org/dokuwiki/doku.php?id=content:tech:keyring
[Rhizome]: http://developer.servalproject.org/dokuwiki/doku.php?id=content:tech:rhizome
[MeshMS]: http://developer.servalproject.org/dokuwiki/doku.php?id=content:tech:meshms
[MDP]: http://developer.servalproject.org/dokuwiki/doku.php?id=content:tech:mdp
[MSP]: http://developer.servalproject.org/dokuwiki/doku.php?id=content:tech:msp
[SID]: http://developer.servalproject.org/dokuwiki/doku.php?id=content:tech:sid
[DID]: http://developer.servalproject.org/dokuwiki/doku.php?id=content:tech:did
[BID]: http://developer.servalproject.org/dokuwiki/doku.php?id=content:tech:bid
[Basic Authentication]: https://en.wikipedia.org/wiki/Basic_access_authentication
[API]: https://en.wikipedia.org/wiki/Application_programming_interface
[HTTP REST]: https://en.wikipedia.org/wiki/Representational_state_transfer
[HTTP 1.0]: http://www.w3.org/Protocols/HTTP/1.0/spec.html
[Intent]: http://developer.android.com/reference/android/content/Intent.html
[Permission]: https://developer.android.com/preview/features/runtime-permissions.html
[configured]: ./Servald-Configuration.md
[Internet Media Type]: https://www.iana.org/assignments/media-types/media-types.xhtml
[JSON]: https://en.wikipedia.org/wiki/JSON
[UTF-8]: https://en.wikipedia.org/wiki/UTF-8
[jq(1)]: https://stedolan.github.io/jq/
[idempotent]: https://en.wikipedia.org/wiki/Idempotence
[Unix time]: https://en.wikipedia.org/wiki/Unix_time
[Y2038 problem]: https://en.wikipedia.org/wiki/Year_2038_problem
[SHA-512]: https://en.wikipedia.org/wiki/SHA-2