Use incoming endpoint instead of hardcoded localhost

src/comments.rs

@@ -1,16 +1,31 @@
 use crate::error::GementionError;
-use crate::models::mentions::{Mention, MentionUpload};
+use crate::models::mentions::{C2SMentionRequest, Mention};
 use crate::models::web::MentionResponse;
-use crate::{verification::verify};
+use crate::validation::Validation;
+use crate::verification::verify;
 use fluffer::Client;
 
-// Receive a mention over Titan.
-// - Make Gemini request to see if target page supports gemention.
-// - If so, store mention in DB.
-pub(crate) async fn receive_mention(client: Client) -> Result<MentionResponse, GementionError> {
-    // TODO change to return MentionResponse or something like that.
-    let titan = MentionUpload::try_from(&client)?;
-    let mut mention = Mention::try_from(titan)?;
+/// Receive a client-to-server Gemention: i.e. a user posting a
+/// comment to a gemention-enabled page. The client must identify
+/// themselves with a cert that at least has a username.
+pub(crate) async fn receive_c2s_gemention(
+    client: Client,
+) -> Result<MentionResponse, GementionError> {
+    let mention_upload = C2SMentionRequest::try_from(&client)?.validate()?;
+    let mut mention = Mention::try_from(mention_upload)?;
+    verify(&mut mention).await?;
+
+    Ok(MentionResponse::from(mention))
+}
+
+/// Receive a server-to-server Gemention: another capsule linking to a
+/// gemention-enabled page on this capsule. There is an exchange of
+/// titan keys so that the servers can talk to one another.
+pub(crate) async fn receive_s2s_gemention(
+    client: Client,
+) -> Result<MentionResponse, GementionError> {
+    let mention_upload = C2SMentionRequest::try_from(&client)?;
+    let mut mention = Mention::try_from(mention_upload)?;
     verify(&mut mention).await?;
 
     Ok(MentionResponse::from(mention))

src/error.rs

@@ -4,6 +4,8 @@ use async_trait::async_trait;
 use fluffer::GemBytes;
 use thiserror::Error;
 
+use crate::validation::c2s::C2SValidationError;
+
 #[derive(Error, Debug)]
 pub(crate) enum GementionError {
     #[error("No content found for target")]
@@ -30,6 +32,9 @@ pub(crate) enum GementionError {
     #[error("value was not utf8: {0}")]
     Utf8Error(#[from] Utf8Error),
 
+    #[error("c2s validation error: {0}")]
+    C2SValidationError(#[from] C2SValidationError),
+
     #[error("generic error: {0}")]
     UnclassifiedError(#[from] anyhow::Error),
 }

src/main.rs

@@ -3,6 +3,7 @@ use fluffer::AppErr;
 mod comments;
 mod error;
 mod models;
+mod validation;
 mod routes;
 mod verification;
 

src/models/mentions.rs

@@ -1,6 +1,7 @@
 use async_trait::async_trait;
 use fluffer::{Client, GemBytes};
 use std::fmt::Display;
+use url::Url;
 
 use crate::error::GementionError;
 
@@ -28,15 +29,20 @@ fn parse_content_body(raw_body: &[u8]) -> Result<&str, GementionError> {
 }
 
 /// Wraps an incoming Titan request and provides handy methods for
-/// extracting the expected information.
-pub(crate) struct MentionUpload<'a> {
+/// extracting the expected information for a client-to-server
+/// gemention.
+pub(crate) struct C2SMentionRequest<'a> {
     client: &'a Client,
+    accessed_url: &'a Url,
 }
 
-impl<'a> MentionUpload<'a> {
-    pub fn from_client(client: &'a Client) -> Result<MentionUpload, GementionError> {
+impl<'a> C2SMentionRequest<'a> {
+    pub fn from_client(client: &'a Client) -> Result<C2SMentionRequest, GementionError> {
         if let Some(_) = client.titan {
-            Ok(Self { client: &client })
+            Ok(Self {
+                client: &client,
+                accessed_url: &client.url,
+            })
         } else {
             Err(GementionError::NotTitanResource)
         }
@@ -58,6 +64,10 @@ impl<'a> MentionUpload<'a> {
         titan!(self).size
     }
 
+    pub fn certificate(&self) -> Option<String> {
+        self.client.certificate()
+    }
+
     pub fn fingerprint(&self) -> Option<String> {
         self.client.fingerprint()
     }
@@ -73,13 +83,18 @@ impl<'a> MentionUpload<'a> {
     pub fn content(&self) -> Result<&str, GementionError> {
         parse_content_body(self.raw_body())
     }
+
+    /// The full URL that was accessed for the incoming request.
+    pub fn accessed_url(&self) -> &Url {
+        self.accessed_url
+    }
 }
 
-impl<'a> TryFrom<&'a Client> for MentionUpload<'a> {
+impl<'a> TryFrom<&'a Client> for C2SMentionRequest<'a> {
     type Error = GementionError;
 
     fn try_from(client: &'a Client) -> Result<Self, Self::Error> {
-        MentionUpload::from_client(client)
+        C2SMentionRequest::from_client(client)
     }
 }
 
@@ -91,6 +106,7 @@ pub(crate) enum MentionType {
 
 #[derive(Debug)]
 pub(crate) struct Mention {
+    receiving_endpoint: Url,
     mention_type: MentionType,
     target: String,
     user: String,
@@ -103,6 +119,14 @@ impl Mention {
         &self.target
     }
 
+    pub fn receiving_endpoint(&self) -> &Url {
+        &self.receiving_endpoint
+    }
+
+    pub fn target_url(&self) -> Url {
+        Url::parse(&format!("gemini://{}", &self.target)).unwrap()
+    }
+
     pub fn mention_type(&self) -> &MentionType {
         &self.mention_type
     }
@@ -125,12 +149,13 @@ impl Mention {
 
     fn valid_gemtext(&self) -> String {
         let headline = format!("## {} from {}", self.mention_type, self.user);
+        let header = format!("=> {} In response to this page", self.target_url());
         let content = match &self.mention_type {
             MentionType::Reply => self.content.clone().unwrap_or(String::from("[no content]")),
             MentionType::Like => format!("{} liked this.", self.user),
         };
 
-        format!("{}\n\n{}", headline, content)
+        format!("{}\n\n{}\n\n### Content\n{}", headline, header, content)
     }
 
     fn invalid_gemtext(&self) -> String {
@@ -182,10 +207,10 @@ impl TryFrom<&[u8]> for MentionType {
     }
 }
 
-impl<'a> TryFrom<MentionUpload<'a>> for Mention {
+impl<'a> TryFrom<C2SMentionRequest<'a>> for Mention {
     type Error = GementionError;
 
-    fn try_from(resource: MentionUpload<'a>) -> Result<Self, Self::Error> {
+    fn try_from(resource: C2SMentionRequest<'a>) -> Result<Self, Self::Error> {
         if resource.mime() == "text/plain" {
             // Be flexible on mention type: if first line isn't a
             // mention type, just assume reply.
@@ -204,6 +229,15 @@ impl<'a> TryFrom<MentionUpload<'a>> for Mention {
                 .username()
                 .ok_or(GementionError::UsernameNotProvided)?;
 
+            let receiving_endpoint = Url::parse(
+                resource
+                    .accessed_url()
+                    .as_str()
+                    .split(&target)
+                    .next()
+                    .ok_or(GementionError::InvalidBody)?,
+            )?;
+
             let content = resource.content()?.to_owned();
             let content = if !content.is_empty() {
                 Some(content)
@@ -216,6 +250,7 @@ impl<'a> TryFrom<MentionUpload<'a>> for Mention {
                 mention_type,
                 content,
                 target,
+                receiving_endpoint,
                 verification_status: VerificationStatus::NotYetVerified,
             })
         } else {

src/models/verification.rs

@@ -1,8 +1,6 @@
 use crate::error::GementionError;
 use std::fmt::Display;
 
-use super::mentions::Mention;
-
 #[derive(Debug)]
 pub(crate) enum VerificationStatus {
     Verified {
@@ -50,7 +48,7 @@ pub(crate) enum VerificationFailureReason {
 
     /// One or more mention links exist, but they are not to this
     /// endpoint, or for this page.
-    MentionLinkIncorrect,
+    MentionLinkIncorrect(String),
 
     /// There was an error during the verification process.
     Error(GementionError),
@@ -60,7 +58,9 @@ impl ToString for VerificationFailureReason {
     fn to_string(&self) -> String {
         match self {
             Self::NoMentionLinkFound => String::from("No mention link found"),
-            Self::MentionLinkIncorrect => String::from("Mention link points to wrong target"),
+            Self::MentionLinkIncorrect(endpoint) => {
+                format!("Target URL does not accept gementions from endpoint: {}", endpoint)
+            }
             Self::Error(err) => err.to_string(),
         }
     }

src/models/web.rs

@@ -12,7 +12,7 @@ impl From<Mention> for MentionResponse {
         match mention.verify_status() {
             VerificationStatus::Verified { .. } => Self::VerifiedMention(mention),
             VerificationStatus::Invalid(_) => Self::InvalidMention(mention),
-            VerificationStatus::NotYetVerified => Self::InvalidMention(mention)
+            VerificationStatus::NotYetVerified => Self::InvalidMention(mention),
         }
     }
 }
@@ -45,9 +45,11 @@ impl MentionResponse {
 
     pub fn description(&self) -> String {
         match self {
-            Self::VerifiedMention(_) => "You have successfully submitted a gemention.",
+            Self::VerifiedMention(_) => {
+                "You have successfully submitted a gemention. It is shown below."
+            }
             Self::InvalidMention(_) => {
-                "There was an error submitting the gemention, detailed below."
+                "There was an error submitting the gemention. The error is detailed below."
             }
             Self::NotTitanRequest => "Your request was not a Titan protocol request.",
         }
@@ -68,7 +70,7 @@ impl GemBytes for MentionResponse {
         let status_line = self.status_line();
         let body = if self.should_have_body() {
             format!(
-                "{}\n\n{}\n\n{},",
+                "{}\n\n{}\n\n{}",
                 self.headline(),
                 self.description(),
                 self.mention_body()

src/routes.rs

@@ -1,10 +1,11 @@
 use fluffer::App;
-use crate::comments::receive_mention;
+use crate::comments::{receive_c2s_gemention, receive_s2s_gemention};
 
 pub(crate) fn create_app() -> App {
     App::default()
-        .titan("/receive/*target", receive_mention, 20_000)
+        .titan("/c2s/receive/*target", receive_c2s_gemention, 2048)
+        .titan("/s2s/receive/*target", receive_s2s_gemention, 2048)
         .route("/", |_| async {
-            "# Welcome\n=> titan://localhost/receive/agnos.is/posts/webmentions-test.gmi Receive Mention"
+            "# Welcome\n=> titan://localhost/c2s/receive/agnos.is/posts/webmentions-test.gmi Receive Mention"
         })
 }

src/validation/c2s.rs

@@ -0,0 +1,28 @@
+use crate::{models::mentions::C2SMentionRequest, error::GementionError};
+use super::Validation;
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+pub enum C2SValidationError {
+    #[error("a username is required on the client certificate")]
+    UsernameRequired,
+
+    #[error("a client certificate is required")]
+    ClientCertificateRequired,
+}
+
+impl Validation for C2SMentionRequest<'_> {
+    type Error = C2SValidationError;
+
+    fn validate(self) -> Result<Self, Self::Error> {
+        if self.username().is_none() {
+            return Err(C2SValidationError::UsernameRequired);
+        }
+
+        if self.certificate().is_none() {
+            return Err(C2SValidationError::ClientCertificateRequired);
+        }
+
+        Ok(self)
+    }
+}

src/validation/mod.rs

@@ -0,0 +1,7 @@
+pub(crate) mod c2s;
+
+pub trait Validation {
+    type Error;
+
+    fn validate(self) -> Result<Self, Self::Error> where Self: Sized;
+}

src/verification/mod.rs

@@ -7,13 +7,12 @@ use crate::error::GementionError;
 use crate::models::mentions::Mention;
 use crate::models::verification::*;
 
-const OUR_ENDPOINT: &'static str = "titan://localhost/receive/";
-
-fn is_mention_link(gemtext_link: &str) -> bool {
-    gemtext_link.starts_with(OUR_ENDPOINT)
+fn is_mention_link(endpoint: &Url, gemtext_link: &str) -> bool {
+    gemtext_link.starts_with(endpoint.as_str())
 }
 
 fn scan_for_gemention_endpoints(
+    endpoint: &Url,
     meta: GeminiMetadata,
     ast: GeminiAst,
 ) -> (VerificationSource, Vec<String>) {
@@ -29,7 +28,7 @@ fn scan_for_gemention_endpoints(
         .inner()
         .into_iter()
         .filter_map(|node| match node {
-            GemtextNode::Link { ref to, .. } if is_mention_link(to) => Some(to),
+            GemtextNode::Link { ref to, .. } if is_mention_link(endpoint, to) => Some(to),
             _ => None,
         })
         .cloned()
@@ -38,14 +37,17 @@ fn scan_for_gemention_endpoints(
     (VerificationSource::Page, endpoints)
 }
 
-fn verify_mentions<S: AsRef<str>>(
-    expected_link: S,
+fn verify_mentions(
+    mention: &mut Mention,
     source_and_endpoints: (VerificationSource, Vec<String>),
-) -> VerificationStatus {
+) -> Result<VerificationStatus, GementionError> {
     let (verification_source, mentions) = source_and_endpoints;
+    // TODO need to normalize url from page as well as ours, to make
+    // sure things like ports being in url or not are handled.
+    let expected_link = mention.receiving_endpoint().join(mention.target())?;
     let expected_link = expected_link.as_ref();
 
-    if mentions.len() > 0 {
+    let verification_status = if mentions.len() > 0 {
         // We have links that go to our endpoint. Scan links for the
         // one we expect (i.e. for the target), otherwise we say
         // incorrect link.
@@ -62,16 +64,19 @@ fn verify_mentions<S: AsRef<str>>(
                 }
             })
             .unwrap_or(VerificationStatus::Invalid(
-                VerificationFailureReason::MentionLinkIncorrect,
+                VerificationFailureReason::MentionLinkIncorrect(
+                    mention.receiving_endpoint().to_string(),
+                ),
             ))
     } else {
         VerificationStatus::Invalid(VerificationFailureReason::NoMentionLinkFound)
-    }
+    };
+
+    Ok(verification_status)
 }
 
 async fn verify_mention(mention: &mut Mention) -> Result<(), GementionError> {
     let url = Url::parse(&format!("gemini://{}", mention.target()))?;
-    let expected_link = Url::parse(OUR_ENDPOINT)?.join(mention.target())?;
 
     let resp = germ_request(&url).await?;
     let meta = GeminiMetadata::from_string(resp.meta());
@@ -82,8 +87,9 @@ async fn verify_mention(mention: &mut Mention) -> Result<(), GementionError> {
         .ok_or(GementionError::NoContentFoundForTarget)?;
 
     let ast = GeminiAst::from_string(content);
-    let source_and_endpoints = scan_for_gemention_endpoints(meta, ast);
-    let status = verify_mentions(expected_link, source_and_endpoints);
+    let source_and_endpoints =
+        scan_for_gemention_endpoints(mention.receiving_endpoint(), meta, ast);
+    let status = verify_mentions(mention, source_and_endpoints)?;
 
     mention.set_verify_status(status);
     Ok(())