Merge branch 'master' into users

CHANGELOG.md

@@ -1,3 +1,13 @@
+# 4.3.0
+
+SMP server:
+
+- additional server usage statistics.
+
+SMP agent:
+
+- increase retry interval when sending messages after ERR QUOTA.
+
 # 4.2.0
 
 SMP agent and server:

package.yaml

@@ -1,5 +1,5 @@
 name: simplexmq
-version: 4.2.3
+version: 4.3.0
 synopsis: SimpleXMQ message broker
 description: |
   This package includes <./docs/Simplex-Messaging-Server.html server>,

rfcs/2022-12-26-simplex-file-transfer.md

@@ -95,10 +95,12 @@ To send the file, the sender will:
 
 - compute SHA512 digest
 - pad the file to match the whole number of chunks in size,
-- encrypt it with a randomly chosen symmetric key and IV (e.g., using NaCL cryptobox),
+- encrypt it with a randomly chosen symmetric key and IV (e.g., using NaCL crypto_secretbox),
 - split into fixed size chunks
 - upload each chunk to a randomly chosen server.
 
+The sending client should generate more per-recipient keys than the actual number of recipients, possibly rounding up to a power of 2, to conceal the actual number of intended recipients.
+
 Then the sending client will combine addresses of all chunks and other information into "file description", different for each file recipient, that will include:
 
 - an encryption key that was used to encrypt the file (the same for all recipients).
@@ -106,22 +108,24 @@ Then the sending client will combine addresses of all chunks and other informati
 - list of chunk descriptions; information for each chunk:
   - private Ed25519 key to sign commands for file transfer server.
   - chunk address (server host and chunk ID).
+  - chunk sha512 digest
 
 To reduce the size, chunk descriptions will be grouped by the server host.
 
-This "file description" itself will be sent as a small file. To estimate its size:
+This "file description" itself will be sent as a small file over an authenticated channel, to prevent file description modification. To estimate its size:
 
 - each chunk \* redundancy per chunk, assuming chunks are grouped per server:
-  - chunk number in the file - 8 bytes (including any overhead)
+  - 1-based chunk number in the file - 8 bytes (including any overhead)
   - Ed25519 key (different for each recipient / chunk combination) - 32 bytes \* 4/3 (base64, assuming text encoding)
   - chunk ID (different for each recipient) - 64 bytes \* 4/3
+  - optional (only in the first chunk occurence) chunk sha512 digests - 64 bytes \* 4/3
 - server addresses - say, 128 bytes per server
 - sha512 digest - 64 bytes \* 4/3
 - encryption key - 32 bytes \* 4/3
 - IV - 32 bytes \* 4/3
 - encoding overhead - say, 256 bytes
 
-For 1gb file, sent via 4 different servers, in 8Mb chunks, with redundancy 2, the size of "file description", assuming text encoding, will be ~34kb (`128 * (8 + 32 + 64) * 2 * 4/3 + 128 * 4 + (64 + 32 + 32) * 4/3 + 256`).
+For 1gb file, sent via 4 different servers, in 8Mb chunks, with redundancy 2, the size of "file description", assuming text encoding, will be ~45kb (`128 * (8 + 32 + 64) * 2 * 4/3 + 128 * 64 * 4/3 + 128 * 4 + (64 + 32 + 32) * 4/3 + 256`).
 
 File description format (yml):
 
@@ -132,11 +136,12 @@ chunk: 8Mb
 hash: abc=
 key: abc=
 iv: abc=
+part_hashes: [def=, def=, def=, def=]
 parts:
   - server: xftp://abc=@example1.com
-    chunks: [1:abc=:def=, 3:abc=:def=]
+    chunks: [1:abc=:def=:ghi=, 3:abc=:def=:ghi=]
   - server: xftp://abc=@example2.com
-    chunks: [2:abc=:def=, 4:abc=:def=]
+    chunks: [2:abc=:def=:ghi=, 4:abc=:def=:ghi=]
   - server: xftp://abc=@example3.com
     chunks: [1:abc=:def=, 4:abc=:def=]
   - server: xftp://abc=@example4.com

simplexmq.cabal

@@ -5,7 +5,7 @@ cabal-version: 1.12
 -- see: https://github.com/sol/hpack
 
 name:           simplexmq
-version:        4.2.3
+version:        4.3.0
 synopsis:       SimpleXMQ message broker
 description:    This package includes <./docs/Simplex-Messaging-Server.html server>,
                 <./docs/Simplex-Messaging-Client.html client> and

src/Simplex/Messaging/Agent/Env/SQLite.hs

@@ -124,9 +124,9 @@ defaultMessageRetryInterval =
         -- to resume sending on QCONT messages.
         -- After that local message expiration period should be also increased.
         RetryInterval
-          { initialInterval = 10_000000,
+          { initialInterval = 30_000000,
             increaseAfter = 30_000000,
-            maxInterval = 300_000000
+            maxInterval = 600_000000
           }
     }