commit 36e4dd2f42d802c965e519111a720775fe7b99e9
author Philipp Hancke <phancke@microsoft.com> Thu Sep 28 09:02:21 2023
committer WebRTC LUCI CQ <webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com> Fri Oct 06 12:25:37 2023
tree 36a1041f323b4af2554831f04a339b3594697049
parent 9cf825ded94e86a4e71c209c74223f6482d63094

Add histogram for DTLS peer signature algorithm

in order to estimate the impact of deprecating SHA1. Chromium UMA CL:
  https://chromium-review.googlesource.com/c/chromium/src/+/4894345

BUG=webrtc:15517

Change-Id: I5216ba2a8cbba2f276af20d31aa5e111e7c3a141
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/321620
Reviewed-by: David Benjamin <davidben@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Philipp Hancke <phancke@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#40882}

pc/peer_connection.cc

diff --git a/pc/peer_connection.cc b/pc/peer_connection.cc
index cde3d91..e349da4 100644
--- a/pc/peer_connection.cc
+++ b/pc/peer_connection.cc
@@ -2885,6 +2885,36 @@
       }
     }
   }
+
+  uint16_t ssl_peer_signature_algorithm =
+      stats.channel_stats[0].ssl_peer_signature_algorithm;
+  if (ssl_peer_signature_algorithm != rtc::kSslSignatureAlgorithmUnknown) {
+    for (cricket::MediaType media_type : media_types) {
+      switch (media_type) {
+        case cricket::MEDIA_TYPE_AUDIO:
+          RTC_HISTOGRAM_ENUMERATION_SPARSE(
+              "WebRTC.PeerConnection.SslPeerSignatureAlgorithm.Audio",
+              ssl_peer_signature_algorithm,
+              rtc::kSslSignatureAlgorithmMaxValue);
+          break;
+        case cricket::MEDIA_TYPE_VIDEO:
+          RTC_HISTOGRAM_ENUMERATION_SPARSE(
+              "WebRTC.PeerConnection.SslPeerSignatureAlgorithm.Video",
+              ssl_peer_signature_algorithm,
+              rtc::kSslSignatureAlgorithmMaxValue);
+          break;
+        case cricket::MEDIA_TYPE_DATA:
+          RTC_HISTOGRAM_ENUMERATION_SPARSE(
+              "WebRTC.PeerConnection.SslPeerSignatureAlgorithm.Data",
+              ssl_peer_signature_algorithm,
+              rtc::kSslSignatureAlgorithmMaxValue);
+          break;
+        default:
+          RTC_DCHECK_NOTREACHED();
+          continue;
+      }
+    }
+  }
 }
 
 bool PeerConnection::OnTransportChanged(