From 6939790caa1d9559365961beaa9b6f48cf33f928 Mon Sep 17 00:00:00 2001 From: randogoth Date: Fri, 9 Oct 2026 09:47:23 +0300 Subject: [PATCH] docs: rewrite landing page as a smolmail primer and fix broken license and reference links --- AGENTS.md | 31 +++ LICENSES/CC-BY-SA-4.0.txt | 428 ++++++++++++++++++++++++++++++++++++++ SPEC.md | 2 +- index.md | 96 +++++++-- 4 files changed, 533 insertions(+), 24 deletions(-) create mode 100644 AGENTS.md create mode 100644 LICENSES/CC-BY-SA-4.0.txt diff --git a/AGENTS.md b/AGENTS.md new file mode 100644 index 0000000..0780b93 --- /dev/null +++ b/AGENTS.md @@ -0,0 +1,31 @@ +# General Working Rules + +## Writing Strings + +- **Plain and direct.** Follow the Microsoft Writing Style Guide. Address the user as "you," use contractions, sentence case, and the fewest words that work. Start with verbs. Prefer simple words ("use," not "utilize"). +- **Actionable UI.** Buttons say what they do ("Save draft," not "OK"). Use input-neutral verbs ("Select," not "click" or "tap"). Errors say what happened and what to do next, without blaming the user or using "invalid," "illegal," or "fatal." +- **No jargon.** Write for non-technical users. Never show raw error codes, exception names, or implementation details on their own. Add a code only after the plain explanation, e.g. "(Error 502)." +- **Consistent terms.** Use one term per concept. Avoid idioms, puns, and abbreviations so strings translate cleanly. +- **Avoid filler.** Don't default to em dashes, "not just X, it's Y" constructions, abstract triads, rhetorical questions, hype adjectives, hedging, or summary lines. Avoid "delve," "leverage," "robust," "seamless," "testament to," and "in today's world." + +## Documentation + +- Keep documentation concise, accurate, and synchronized with the implementation. +- Distinguish implemented behavior from proposals and historical plans. Remove outdated information and shorten resolved findings. +- Update specifications alongside changes to interfaces, formats, and contracts. Record important decisions where they are enforced. +- **Natural reflow.** Write paragraphs as continuous lines without hard wrapping. Use blank lines between paragraphs and explicit line breaks only where structurally necessary. + +## Working Style + +- **Inspect first.** Examine existing code, configuration, architecture, and conventions rather than assuming how things work. +- **Respect scope.** Follow the latest explicit instructions. Do not make unrelated changes or resume superseded tasks. +- **Work silently.** No progress narration or request recaps. Interrupt only for genuine blockers or discoveries that materially change the approach. +- **Resolve uncertainty.** Investigate missing information before asking. Never invent requirements or assume unverified behavior. +- **Respect user decisions.** Identify significant design problems and propose concrete alternatives with trade-offs, but follow the user's choice. +- **Respect authorization.** Observe approval requirements for changes, tests, commits, deployments, and destructive operations. +- **Commit messages.** Use concise, single-line, tag-prefixed messages (e.g., fix:, feat:, refactor:, docs:). Describe what changed using the imperative mood. +- **No credit notes.** Omit attribution, co-author trailers, AI-generated notices, and other credit statements from commits and generated documentation. + +## Completion + +Summarize changes, verification results, important decisions, and unresolved issues in a few sentences. Avoid lengthy reports unless requested. \ No newline at end of file diff --git a/LICENSES/CC-BY-SA-4.0.txt b/LICENSES/CC-BY-SA-4.0.txt new file mode 100644 index 0000000..2d58298 --- /dev/null +++ b/LICENSES/CC-BY-SA-4.0.txt @@ -0,0 +1,428 @@ +Attribution-ShareAlike 4.0 International + +======================================================================= + +Creative Commons Corporation ("Creative Commons") is not a law firm and +does not provide legal services or legal advice. Distribution of +Creative Commons public licenses does not create a lawyer-client or +other relationship. Creative Commons makes its licenses and related +information available on an "as-is" basis. Creative Commons gives no +warranties regarding its licenses, any material licensed under their +terms and conditions, or any related information. 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Except for the limited purpose of indicating that +material is shared under a Creative Commons public license or as +otherwise permitted by the Creative Commons policies published at +creativecommons.org/policies, Creative Commons does not authorize the +use of the trademark "Creative Commons" or any other trademark or logo +of Creative Commons without its prior written consent including, +without limitation, in connection with any unauthorized modifications +to any of its public licenses or any other arrangements, +understandings, or agreements concerning use of licensed material. For +the avoidance of doubt, this paragraph does not form part of the +public licenses. + +Creative Commons may be contacted at creativecommons.org. + diff --git a/SPEC.md b/SPEC.md index 4b3eb6d..4651b3e 100644 --- a/SPEC.md +++ b/SPEC.md @@ -371,7 +371,7 @@ Reticulum replaces the transport of §4. It does not wrap it. An address grows a RNS facts cited below were read from Reticulum 1.5.4. Constants in that stack are version-dependent and some are undocumented, so an implementation MUST read them from the stack at runtime rather than compile them from this text, and SHOULD state the version it was tested against. A reader who finds a figure here contradicted by the stack SHOULD believe the stack. -[smolmail_rns.py](smolmail_rns.py) and [smolmaild_rns.py](smolmaild_rns.py) are a reference client and server for this transport, tested against Reticulum 1.5.4. +[smolmail_rns.py](https://code.randogoth.com/randogoth/smolmail/src/branch/main/smolmail_rns.py) and [smolmaild_rns.py](https://code.randogoth.com/randogoth/smolmail/src/branch/main/smolmaild_rns.py) are a reference client and server for this transport, tested against Reticulum 1.5.4. ### 13.1 Server destination diff --git a/index.md b/index.md index ca707b3..dbd5ec4 100644 --- a/index.md +++ b/index.md @@ -1,49 +1,99 @@ # smolmail -A small decentralised mail protocol with cypherpunk leanings, encrypted end to end. It is simple enough that writing your own client is an afternoon of fun. +A small, decentralised mail system where every message is encrypted end to end. It's simple enough that you can write your own client in an afternoon. -You get an address, a key and a message. That's all there is to it. +- **One key is your identity.** Back up 32 bytes and you've backed up everything. +- **Only the recipient can read your mail.** Servers store sealed envelopes they can't open. +- **No middlemen.** Your client delivers straight to the recipient's server. -There are five operations and no way to add more. Underneath sit four cryptographic primitives that have been around long enough to be boring. Your identity is a single 32-byte key, and that key is the only thing you ever have to back up. Nothing expires, and nobody vouches for anybody: you pin a server's key the first time you connect, and from then on your client only has to check that it still matches. +[Open webmail](https://webmail.smol.place) · [Read the specification](SPEC.md) -Each message is sealed with a key that exists for that message alone and is discarded straight after, which leaves nothing behind to trace or to forge. +## How smolmail compares -Keeping spam out does not require anyone to read your mail. Every mailbox has a limit on how much it will hold, and a stranger needs a token from you before the server will accept their message. The server can turn mail away, but it cannot open it. Your client talks straight to the recipient's server, with nothing in between. +| | Email | PGP email | smolmail | +| --- | --- | --- | --- | +| Server reads mail | Yes | No | No | +| Server sees sender | Yes | Yes | No | +| Spam filter reads mail | Yes | Partly | No | +| Relayed by other servers | Yes | Yes | No | +| Needs the internet | Yes | Yes | No\* | -Your name is yours on that server because you signed for it with your key, and nobody without that key can claim it. If you ever have to switch keys, your old key signs over to the new one and your name follows. Messages still sent to the old key arrive as before, so contacts can catch up in their own time. +\* Only when the server is also reachable over Reticulum. See "Beyond the internet" below. -## Send your first message +## Get started -Get started with a @smol.place address. Pin our server's public key before you connect: +### Use webmail -> `po3cxpzjrt73dypt2rplskbkywizr44afhqthaa5x47mfpe4kesq` +Go to [webmail.smol.place](https://webmail.smol.place) to register a @smol.place address and start sending encrypted mail. Nothing to install. -Your smol mail client checks it on every connection, so you always know you're talking to us and never an impostor. +A browser client depends on the site that serves it, because the code is loaded fresh each time you open the page. For long-term use, a native client that pins our server key gives you stronger guarantees. -Not sure what any of this means? No problem! Just visit our [Webmail Client](http://webmail.smol.place) to register your address and start sending encrypted messages. +### Use a native client -## Identity +Connect to `smol.place` on port `1961`, and pin this server key before you connect: -The only secret is a 32-byte master. Back that up and nothing else: the Ed25519 signing key, the encryption key derived from it, and the key that issues accept tokens all come out of it. One thing to hold, move between servers, print on paper or scan from a screen. +> `po3cxpzjrt73dypt2rplskbkywizr44afhqthaa5x47mfpe4kesq` -Signatures prove authorship. A throwaway key per message means a stolen identity key cannot decrypt anything already sent. +Your client checks the key every time it connects, so it always knows it's talking to us and not an impostor. -## Addressing +### Write your own client + +The whole protocol is five operations and four well-known cryptographic building blocks, with no extensions and nothing to negotiate. [SPEC.md](SPEC.md) has everything you need. + +## How it works + +### Your key is you + +Your identity is a single 32-byte secret called the master. Your signing key, your encryption key and the key that lets people write to you all come from it. Back up the master and nothing else. You can print it on paper or scan it from a screen. ([SPEC §2](SPEC.md#2-identity)) + +### Your address ``` -alice@example.org short form, resolved via the server -smol://alice@example.org/mfrggzdfmztwq2lknnwg23tpo… self-certifying, carries its own key +alice@smol.place short form, looked up on the server +smol://alice@smol.place/mfrggzdfmztwq2lknnwg23tpo… full form, carries alice's key ``` -The short form is typeable. The long form carries the key itself, so an address shared by QR code, contact file or link needs no trust in any server at all. Either way, changing servers never changes an identity. +The short form is easy to type. The full form contains the key itself, so a contact you add from a link or QR code doesn't depend on any server telling the truth. To check a contact in person or on the phone, compare fingerprints: the first 20 characters of the key, read in groups of four. ([SPEC §3](SPEC.md#3-addressing)) -Keys learned from a server are pinned on first use. Later changes need a rotation certificate signed by the previous key, or explicit confirmation. +### Every message is sealed -## Cryptography +Each message is locked with a key made for that message alone, then thrown away. The envelope names the recipient but not the sender, so the server can't see who writes to whom. Inside, the message is signed, so the recipient knows who wrote it and that nobody changed it. ([SPEC §5](SPEC.md#5-message-format)) -Ed25519 · X25519 · ChaCha20-Poly1305 · SHA-256. Four established primitives, no novel cryptography, nothing else anywhere in the protocol. Transport is TCP with a Noise handshake. No certificates, no CA, no expiry. +### Mail from strangers + +Servers can't read your mail, so they can't filter spam by content. Instead, you give each person you correspond with an accept token. Mail that carries a token goes to your main mailbox. Mail without one goes to a small requests area that holds less and clears out sooner. Anyone can still write to you, but nobody can fill your mailbox. Your client decides what to do with each message after opening it. ([SPEC §5.8](SPEC.md#58-accept-tokens)) + +### Changing keys + +If you need a new key, your old key and your new key both sign a handover, and your address moves to the new key. Mail sent to your old key still arrives, so your contacts can catch up in their own time. Clients show you when a contact's key changes. ([SPEC §7](SPEC.md#7-key-rotation)) + +## What smolmail protects + +The server learns which mailbox each message is for, its size, when it arrived and was collected, and the IP address you connect from. It doesn't learn the sender, the subject, the content or which messages belong together. + +Some things smolmail doesn't protect: + +- **Your stored mail, if your master is stolen.** Someone holding your master can read every message you've received that's still stored. Keep it safe. Your master can't open mail you've sent to others, because the key that sealed it was thrown away. +- **Who wrote a message.** Messages are signed, so a recipient can prove to others that you wrote it. +- **Traffic patterns.** Someone watching the network can see when you connect and how much you send. + +Messages don't stay on the server forever. Mail in your main mailbox is kept for 30 days and mail in requests for 7 days, unless you delete it sooner. ([SPEC §9](SPEC.md#9-privacy), [§10](SPEC.md#10-servers)) + +## Beyond the internet + +- **Reticulum.** A smolmail server can be reachable over the Reticulum network, which runs over LoRa radio, packet radio, serial links and more, with no DNS or internet needed. Your identity and messages work the same on either network. ([SPEC §13](SPEC.md#13-reticulum-transport)) +- **Tor.** A server can run as a Tor onion service to hide where people connect from. No protocol changes are needed. ([SPEC §9](SPEC.md#9-privacy)) +- **Browsers and restricted networks.** Browsers can't open a direct connection to port 1961, so smolmail can travel through a WebSocket on port 443. The encryption and the server key check stay exactly the same. ([WS.md](WS.md)) + +## Run your own server + +Servers never talk to each other. Each one is an independent mailbox store, so running one is a small job. Anyone with a smolmail address can write to anyone on any other server. + +The [reference client and server](https://code.randogoth.com/randogoth/smolmail) are written in Python, for both TCP and Reticulum. The [gsmol](https://code.randogoth.com/randogoth/gsmol) bridge carries smolmail over WebSocket. ## Specification -[SPEC.md](SPEC.md): wire format, operations, trust model and conformance. -[WS.md](WS.md): smolmail over WebSocket annex. +- [SPEC.md](SPEC.md): smolmail protocol, version 1.2. Message format, operations, trust model and conformance. +- [WS.md](WS.md): smolmail over WebSocket. + +The specification is licensed under [CC BY-SA 4.0](LICENSES/CC-BY-SA-4.0.txt).