feat: implement kernel / initrd oci image support (#103)

* feat: implement kernel / initrd oci image support

* fix: implement image urls more faithfully

crates/oci/src/fetch.rs

@@ -217,6 +217,13 @@ impl OciImageFetcher {
                         continue;
                     }
                 }
+
+                if let Some(ref digest) = image.digest {
+                    if digest != manifest.digest() {
+                        continue;
+                    }
+                }
+
                 found = Some(manifest);
                 break;
             }
@@ -240,7 +247,7 @@ impl OciImageFetcher {
 
         let mut client = OciRegistryClient::new(image.registry_url()?, self.platform.clone())?;
         let (manifest, descriptor, digest) = client
-            .get_manifest_with_digest(&image.name, &image.reference)
+            .get_manifest_with_digest(&image.name, image.reference.as_ref(), image.digest.as_ref())
             .await?;
         let descriptor = descriptor.unwrap_or_else(|| {
             DescriptorBuilder::default()

crates/oci/src/name.rs

@@ -2,33 +2,39 @@ use anyhow::Result;
 use std::fmt;
 use url::Url;
 
-const DOCKER_HUB_MIRROR: &str = "mirror.gcr.io";
-const DEFAULT_IMAGE_TAG: &str = "latest";
-
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct ImageName {
     pub hostname: String,
     pub port: Option<u16>,
     pub name: String,
-    pub reference: String,
+    pub reference: Option<String>,
+    pub digest: Option<String>,
 }
 
 impl fmt::Display for ImageName {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        if DOCKER_HUB_MIRROR == self.hostname && self.port.is_none() {
+        let mut suffix = String::new();
+
+        if let Some(ref reference) = self.reference {
+            suffix.push(':');
+            suffix.push_str(reference);
+        }
+
+        if let Some(ref digest) = self.digest {
+            suffix.push('@');
+            suffix.push_str(digest);
+        }
+
+        if ImageName::DOCKER_HUB_MIRROR == self.hostname && self.port.is_none() {
             if self.name.starts_with("library/") {
-                write!(f, "{}:{}", &self.name[8..], self.reference)
+                write!(f, "{}{}", &self.name[8..], suffix)
             } else {
-                write!(f, "{}:{}", self.name, self.reference)
+                write!(f, "{}{}", self.name, suffix)
             }
         } else if let Some(port) = self.port {
-            write!(
-                f,
-                "{}:{}/{}:{}",
-                self.hostname, port, self.name, self.reference
-            )
+            write!(f, "{}:{}/{}{}", self.hostname, port, self.name, suffix)
         } else {
-            write!(f, "{}/{}:{}", self.hostname, self.name, self.reference)
+            write!(f, "{}/{}{}", self.hostname, self.name, suffix)
         }
     }
 }
@@ -41,13 +47,21 @@ impl Default for ImageName {
 }
 
 impl ImageName {
+    pub const DOCKER_HUB_MIRROR: &'static str = "registry.docker.io";
+    pub const DEFAULT_IMAGE_TAG: &'static str = "latest";
+
     pub fn parse(name: &str) -> Result<Self> {
         let full_name = name.to_string();
         let name = full_name.clone();
         let (mut hostname, mut name) = name
             .split_once('/')
             .map(|x| (x.0.to_string(), x.1.to_string()))
-            .unwrap_or_else(|| (DOCKER_HUB_MIRROR.to_string(), format!("library/{}", name)));
+            .unwrap_or_else(|| {
+                (
+                    ImageName::DOCKER_HUB_MIRROR.to_string(),
+                    format!("library/{}", name),
+                )
+            });
 
         // heuristic to find any docker hub image formats
         // that may be in the hostname format. for example:
@@ -55,7 +69,7 @@ impl ImageName {
         // and neither will abc/hello/xyz:latest
         if !hostname.contains('.') && full_name.chars().filter(|x| *x == '/').count() == 1 {
             name = format!("{}/{}", hostname, name);
-            hostname = DOCKER_HUB_MIRROR.to_string();
+            hostname = ImageName::DOCKER_HUB_MIRROR.to_string();
         }
 
         let (hostname, port) = if let Some((hostname, port)) = hostname
@@ -66,15 +80,54 @@ impl ImageName {
         } else {
             (hostname, None)
         };
-        let (name, reference) = name
-            .split_once(':')
-            .map(|x| (x.0.to_string(), x.1.to_string()))
-            .unwrap_or((name.to_string(), DEFAULT_IMAGE_TAG.to_string()));
+
+        let name_has_digest = if name.contains('@') {
+            let digest_start = name.chars().position(|c| c == '@');
+            let ref_start = name.chars().position(|c| c == ':');
+            if let (Some(digest_start), Some(ref_start)) = (digest_start, ref_start) {
+                digest_start < ref_start
+            } else {
+                true
+            }
+        } else {
+            false
+        };
+
+        let (name, digest) = if name_has_digest {
+            name.split_once('@')
+                .map(|(name, digest)| (name.to_string(), Some(digest.to_string())))
+                .unwrap_or_else(|| (name, None))
+        } else {
+            (name, None)
+        };
+
+        let (name, reference) = if name.contains(':') {
+            name.split_once(':')
+                .map(|(name, reference)| (name.to_string(), Some(reference.to_string())))
+                .unwrap_or((name, None))
+        } else {
+            (name, None)
+        };
+
+        let (reference, digest) = if let Some(reference) = reference {
+            if let Some(digest) = digest {
+                (Some(reference), Some(digest))
+            } else {
+                reference
+                    .split_once('@')
+                    .map(|(reff, digest)| (Some(reff.to_string()), Some(digest.to_string())))
+                    .unwrap_or_else(|| (Some(reference), None))
+            }
+        } else {
+            (None, digest)
+        };
+
         Ok(ImageName {
             hostname,
             port,
             name,
             reference,
+            digest,
         })
     }
 

crates/oci/src/packer/cache.rs

@@ -159,7 +159,9 @@ impl OciPackerCache {
         let image_name = packed.name.to_string();
         annotations.insert(ANNOTATION_IMAGE_NAME.to_string(), image_name);
         let image_ref = packed.name.reference.clone();
-        annotations.insert(ANNOTATION_REF_NAME.to_string(), image_ref);
+        if let Some(image_ref) = image_ref {
+            annotations.insert(ANNOTATION_REF_NAME.to_string(), image_ref);
+        }
         descriptor.set_annotations(Some(annotations));
         manifests.push(descriptor.clone());
         index.set_manifests(manifests);

crates/oci/src/packer/service.rs

@@ -61,6 +61,10 @@ impl OciPackerService {
         digest: &str,
         format: OciPackedFormat,
     ) -> Result<Option<OciPackedImage>> {
+        if digest.contains('/') || digest.contains('\\') || digest.contains("..") {
+            return Ok(None);
+        }
+
         self.cache
             .recall(ImageName::parse("cached:latest")?, digest, format)
             .await

crates/oci/src/registry.rs

@@ -7,7 +7,7 @@ use reqwest::{Client, RequestBuilder, Response, StatusCode};
 use tokio::{fs::File, io::AsyncWriteExt};
 use url::Url;
 
-use crate::{progress::OciBoundProgress, schema::OciSchema};
+use crate::{name::ImageName, progress::OciBoundProgress, schema::OciSchema};
 
 #[derive(Clone, Debug)]
 pub struct OciPlatform {
@@ -176,7 +176,7 @@ impl OciRegistryClient {
         let url = self.url.join(&format!(
             "/v2/{}/manifests/{}",
             name.as_ref(),
-            reference.as_ref()
+            reference.as_ref(),
         ))?;
         let accept = format!(
             "{}, {}, {}, {}",
@@ -202,13 +202,20 @@ impl OciRegistryClient {
     pub async fn get_manifest_with_digest<N: AsRef<str>, R: AsRef<str>>(
         &mut self,
         name: N,
-        reference: R,
+        reference: Option<R>,
+        digest: Option<N>,
     ) -> Result<(OciSchema<ImageManifest>, Option<Descriptor>, String)> {
-        let url = self.url.join(&format!(
-            "/v2/{}/manifests/{}",
-            name.as_ref(),
-            reference.as_ref()
-        ))?;
+        let what = digest
+            .as_ref()
+            .map(|x| x.as_ref().to_string())
+            .unwrap_or_else(|| {
+                reference
+                    .map(|x| x.as_ref().to_string())
+                    .unwrap_or_else(|| ImageName::DEFAULT_IMAGE_TAG.to_string())
+            });
+        let url = self
+            .url
+            .join(&format!("/v2/{}/manifests/{}", name.as_ref(), what,))?;
         let accept = format!(
             "{}, {}, {}, {}",
             MediaType::ImageManifest.to_docker_v2s2()?,
@@ -239,9 +246,10 @@ impl OciRegistryClient {
         let digest = response
             .headers()
             .get("Docker-Content-Digest")
-            .ok_or_else(|| anyhow!("fetching manifest did not yield a content digest"))?
-            .to_str()?
-            .to_string();
+            .and_then(|x| x.to_str().ok())
+            .map(|x| x.to_string())
+            .or_else(|| digest.map(|x: N| x.as_ref().to_string()))
+            .ok_or_else(|| anyhow!("fetching manifest did not yield a content digest"))?;
         let bytes = response.bytes().await?;
         let manifest = serde_json::from_slice(&bytes)?;
         Ok((OciSchema::new(bytes.to_vec(), manifest), None, digest))