Merge pull request 'ref: print succinct or detailed information about a cert' (#3) from fcuny/rendering into main

Reviewed-on: https://git.fcuny.net/fcuny/x509-info/pulls/3

3 files changed, 106 insertions, 71 deletions

diff --git a/src/x509-info/.drone.yml b/src/x509-info/.drone.yml
index f3ec80f..7c469a4 100644
--- a/src/x509-info/.drone.yml
+++ b/src/x509-info/.drone.yml
@@ -33,6 +33,7 @@ steps:
       - nix develop --command cargo test
       - nix build .
       - nix run . -- fcuny.net
+      - nix run . -- --format long fcuny.net
 ---
 kind: pipeline
 type: docker
diff --git a/src/x509-info/src/main.rs b/src/x509-info/src/main.rs
index 99d2c65..d9eed13 100644
--- a/src/x509-info/src/main.rs
+++ b/src/x509-info/src/main.rs
@@ -1,8 +1,8 @@
 extern crate webpki_roots;
 
 mod client;
+mod output;
 
-use chrono::TimeZone as _;
 use clap::Parser;
 use x509_parser::prelude::*;
 
@@ -15,6 +15,9 @@ struct Args {
     /// Port to check
     #[clap(short, long, default_value_t = 443)]
     port: u16,
+
+    #[clap(short, long,value_enum, default_value_t = output::OutputFormat::Short)]
+    format: output::OutputFormat,
 }
 
 fn main() {
@@ -28,7 +31,7 @@ fn main() {
         Ok(certs) => {
             let (_, cert) =
                 x509_parser::certificate::X509Certificate::from_der(certs[0].as_ref()).unwrap();
-            pretty_print(cert);
+            output::OutputFormat::print(args.format, cert);
         }
         Err(e) => {
             println!("error: {}", e);
@@ -36,72 +39,3 @@ fn main() {
         }
     };
 }
-
-fn pretty_print(cert: X509Certificate) {
-    println!(
-        "\tSubject: CN={} O={} L={}",
-        cert.subject()
-            .iter_common_name()
-            .next()
-            .and_then(|cn| cn.as_str().ok())
-            .unwrap(),
-        cert.subject()
-            .iter_organization()
-            .next()
-            .and_then(|o| o.as_str().ok())
-            .unwrap_or_default(),
-        cert.subject()
-            .iter_locality()
-            .next()
-            .and_then(|l| l.as_str().ok())
-            .unwrap_or_default(),
-    );
-    println!(
-        "\tIssuer:  CN={} O={} L={}",
-        cert.issuer()
-            .iter_common_name()
-            .next()
-            .and_then(|cn| cn.as_str().ok())
-            .unwrap(),
-        cert.issuer()
-            .iter_organization()
-            .next()
-            .and_then(|o| o.as_str().ok())
-            .unwrap_or_default(),
-        cert.issuer()
-            .iter_locality()
-            .next()
-            .and_then(|l| l.as_str().ok())
-            .unwrap_or_default(),
-    );
-
-    let not_before = chrono::Local
-        .timestamp(cert.validity().not_before.timestamp(), 0)
-        .to_rfc3339();
-
-    let not_after = chrono::Local
-        .timestamp(cert.validity().not_after.timestamp(), 0)
-        .to_rfc3339();
-
-    if let Some(subnames) = subject_alternative_name(cert) {
-        let dns_names = subnames.join(", ");
-        println!("\tDNS Names: {}", dns_names);
-    }
-
-    println!("\tValidity Period");
-    println!("\t\tNot before: {}", not_before);
-    println!("\t\tNot After:  {}", not_after);
-}
-
-fn subject_alternative_name(cert: X509Certificate) -> Option<Vec<String>> {
-    let mut subnames = Vec::new();
-    if let Ok(Some(san)) = cert.subject_alternative_name() {
-        let san = san.value;
-        for name in &san.general_names {
-            if let GeneralName::DNSName(name) = name {
-                subnames.push(name.to_string());
-            }
-        }
-    }
-    Some(subnames)
-}
diff --git a/src/x509-info/src/output.rs b/src/x509-info/src/output.rs
new file mode 100644
index 0000000..7cfa13e
--- /dev/null
+++ b/src/x509-info/src/output.rs
@@ -0,0 +1,100 @@
+use chrono::prelude::*;
+use std::net::{Ipv4Addr, Ipv6Addr};
+use x509_parser::prelude::*;
+
+/// How to format the output data.
+#[derive(PartialEq, Eq, Debug, Copy, Clone, clap::ValueEnum)]
+pub enum OutputFormat {
+    /// Format the output as one line of plain text.
+    Short,
+
+    /// Format the output as plain text.
+    Long,
+}
+
+impl OutputFormat {
+    pub fn print(self, cert: X509Certificate) {
+        match self {
+            Self::Short => {
+                self.short(cert);
+            }
+            Self::Long => {
+                self.to_text(cert);
+            }
+        }
+    }
+
+    fn short(self, cert: X509Certificate) {
+        let not_after = chrono::Local.timestamp(cert.validity().not_after.timestamp(), 0);
+        let now: DateTime<Local> = Local::now();
+        let remaining = not_after - now;
+        println!(
+            "{} is valid until {} ({} days left)",
+            cert.subject()
+                .iter_common_name()
+                .next()
+                .and_then(|cn| cn.as_str().ok())
+                .unwrap(),
+            not_after.to_rfc2822(),
+            remaining.num_days(),
+        );
+    }
+
+    fn to_text(self, cert: X509Certificate) {
+        let not_before = chrono::Local.timestamp(cert.validity().not_before.timestamp(), 0);
+        let not_after = chrono::Local.timestamp(cert.validity().not_after.timestamp(), 0);
+        let now: DateTime<Local> = Local::now();
+        let remaining = not_after - now;
+        let validity_duration = not_after - not_before;
+
+        println!("certificate");
+        println!(" version: {}", cert.version);
+        println!(" serial: {}", cert.tbs_certificate.raw_serial_as_string());
+        println!(" subject: {}", cert.subject());
+        println!(" issuer: {}", cert.issuer());
+
+        println!(" validity");
+        println!("  not before    : {}", not_before.to_rfc2822());
+        println!("  not after     : {}", not_after.to_rfc2822());
+        println!("  validity days : {}", validity_duration.num_days());
+        println!("  remaining days: {}", remaining.num_days());
+
+        println!(" SANs:");
+        if let Some(subnames) = subject_alternative_name(cert) {
+            for name in subnames {
+                println!("  {}", name);
+            }
+        }
+    }
+}
+
+fn subject_alternative_name(cert: X509Certificate) -> Option<Vec<String>> {
+    let mut subnames = Vec::new();
+    if let Ok(Some(san)) = cert.subject_alternative_name() {
+        let san = san.value;
+        for name in &san.general_names {
+            let s = match name {
+                GeneralName::DNSName(s) => format!("DNS:{}", s),
+                GeneralName::IPAddress(b) => {
+                    let ip = match b.len() {
+                        4 => {
+                            let b = <[u8; 4]>::try_from(*b).unwrap();
+                            let ip = Ipv4Addr::from(b);
+                            format!("{}", ip)
+                        }
+                        16 => {
+                            let b = <[u8; 16]>::try_from(*b).unwrap();
+                            let ip = Ipv6Addr::from(b);
+                            format!("{}", ip)
+                        }
+                        l => format!("invalid (len={})", l),
+                    };
+                    format!("IP address:{}", ip)
+                }
+                _ => format!("{:?}", name),
+            };
+            subnames.push(s);
+        }
+    }
+    Some(subnames)
+}