fix: use existing query params from blobstore response (#136)

Signed-off-by: Daniel Robinson <daniel.robinson@pebble.tv>

src/OrasProject.Oras/Content/Digest.cs

@@ -13,26 +13,37 @@
 
 using OrasProject.Oras.Exceptions;
 using System;
+using System.Collections.Generic;
 using System.Security.Cryptography;
 using System.Text.RegularExpressions;
 
 namespace OrasProject.Oras.Content;
 
 internal static class Digest
 {
-    private const string digestRegexPattern = @"[a-z0-9]+(?:[.+_-][a-z0-9]+)*:[a-zA-Z0-9=_-]+";
-    private static readonly Regex digestRegex = new Regex(digestRegexPattern, RegexOptions.Compiled);
+    private const string _digestRegexPattern = @"[a-z0-9]+(?:[.+_-][a-z0-9]+)*:[a-zA-Z0-9=_-]+";
+    private static readonly Regex _digestRegex = new Regex(_digestRegexPattern, RegexOptions.Compiled);
+
+    // List of registered and supported algorithms as per the specification
+    private static readonly HashSet<string> _supportedAlgorithms = new HashSet<string> { "sha256", "sha512" };
 
     /// <summary>
     /// Verifies the digest header and throws an exception if it is invalid.
     /// </summary>
     /// <param name="digest"></param>
     internal static string Validate(string? digest)
     {
-        if (string.IsNullOrEmpty(digest) || !digestRegex.IsMatch(digest))
+        if (string.IsNullOrEmpty(digest) || !_digestRegex.IsMatch(digest))
         {
             throw new InvalidDigestException($"Invalid digest: {digest}");
         }
+
+        var algorithm = digest.Split(':')[0];
+        if (!_supportedAlgorithms.Contains(algorithm))
+        {
+            throw new InvalidDigestException($"Unrecognized, unregistered or unsupported digest algorithm: {algorithm}");
+        }
+
         return digest;
     }
 
@@ -48,4 +59,4 @@ internal static string ComputeSHA256(byte[] content)
         var output = $"sha256:{BitConverter.ToString(hash).Replace("-", "")}";
         return output.ToLower();
     }
-}
+}

src/OrasProject.Oras/Registry/Remote/BlobStore.cs

@@ -152,7 +152,7 @@ public async Task PushAsync(Descriptor expected, Stream content, CancellationTok
         // add digest key to query string with expected digest value
         var req = new HttpRequestMessage(HttpMethod.Put, new UriBuilder(url)
         {
-            Query = $"digest={HttpUtility.UrlEncode(expected.Digest)}"
+            Query = $"{url.Query}&digest={HttpUtility.UrlEncode(expected.Digest)}"
         }.Uri);
         req.Content = new StreamContent(content);
         req.Content.Headers.ContentLength = expected.Size;

src/OrasProject.Oras/Registry/Remote/HttpResponseMessageExtensions.cs

@@ -25,6 +25,8 @@ namespace OrasProject.Oras.Registry.Remote;
 
 internal static class HttpResponseMessageExtensions
 {
+    private const string _dockerContentDigestHeader = "Docker-Content-Digest";
+
     /// <summary>
     /// Parses the error returned by the remote registry.
     /// </summary>
@@ -75,7 +77,7 @@ public static async Task<Exception> ParseErrorResponseAsync(this HttpResponseMes
     /// <exception cref="NotImplementedException"></exception>
     public static void VerifyContentDigest(this HttpResponseMessage response, string expected)
     {
-        if (!response.Content.Headers.TryGetValues("Docker-Content-Digest", out var digestValues))
+        if (!response.Headers.TryGetValues(_dockerContentDigestHeader, out var digestValues))
         {
             return;
         }
@@ -154,7 +156,7 @@ public static async Task<Descriptor> GenerateDescriptorAsync(this HttpResponseMe
 
         // 4. Validate Server Digest (if present)
         string? serverDigest = null;
-        if (response.Content.Headers.TryGetValues("Docker-Content-Digest", out var serverHeaderDigest))
+        if (response.Headers.TryGetValues(_dockerContentDigestHeader, out var serverHeaderDigest))
         {
             serverDigest = serverHeaderDigest.FirstOrDefault();
             if (!string.IsNullOrEmpty(serverDigest))

tests/OrasProject.Oras.Tests/Content/ContentTest.cs

@@ -12,13 +12,15 @@
 // limitations under the License.
 
 using OrasProject.Oras.Content;
+using OrasProject.Oras.Exceptions;
 using System.Text;
 using Xunit;
 
 namespace OrasProject.Oras.Tests.Content;
 
 public class CalculateDigest
 {
+
     /// <summary>
     /// This method tests if the digest is calculated properly
     /// </summary>
@@ -30,4 +32,39 @@ public void VerifiesIfDigestMatches()
         var calculateHelloWorldDigest = Digest.ComputeSHA256(content);
         Assert.Equal(helloWorldDigest, calculateHelloWorldDigest);
     }
+
+    /// <summary>
+    /// This method tests if the digest validation passes for registered algorithms
+    /// </summary>
+    [Theory]
+    [InlineData("sha256:6c3c624b58dbbcd3c0dd82b4c53f04194d1247c6eebdaab7c610cf7d66709b3b")]
+    [InlineData("sha512:401b09eab3c013d4ca54922bb802bec8fd5318192b0a75f201d8b372742c513925d98f76b340d9e59a4efdc45db9f5c640a21831b3d08be")]
+    public void Validate_ReturnsDigest_ForRegisteredAlgorithms(string validDigest)
+    {
+        var result = Digest.Validate(validDigest);
+        Assert.Equal(validDigest, result);
+    }
+
+    /// <summary>
+    /// This method tests if the digest validation throws an exception for unregistered or unsupported algorithms
+    /// </summary>
+    [Theory]
+    [InlineData("md5:098f6bcd4621d373cade4e832627b4f6")] // MD5, unregistered digest
+    [InlineData("sha1:3b8b5a6b79f6d1114a7b7e95b3e3bc74dd1b6a2a")] // SHA-1, unregistered digest
+    [InlineData("multihash+base58:QmRZxt2b1FVZPNqd8hsiykDL3TdBDeTSPX9Kv46HmX4Gx8")] // Multihash, unregistered digest
+    public void Validate_ThrowsException_ForUnregisteredAlgorithms(string invalidDigest)
+    {
+        Assert.Throws<InvalidDigestException>(() => Digest.Validate(invalidDigest));
+    }
+
+    /// <summary>
+    /// This method tests if the digest validation throws an exception for various invalid digest formats
+    /// </summary>
+    [Theory]
+    [InlineData("sha256:")] // Missing encoded portion
+    [InlineData("sha256+b64u!LCa0a2j_xo_5m0U8HTBBNBNCLXBkg7-g-YpeiGJm564")] // Invalid character in encoded portion
+    public void Validate_ThrowsException_ForInvalidDigestFormats(string invalidDigest)
+    {
+        Assert.Throws<InvalidDigestException>(() => Digest.Validate(invalidDigest));
+    }
 }