Provide a builtin default for $NIX_SSL_CERT_FILE

This is mostly to ensure that when Nix is started on macOS via a
launchd service or sshd (for a remote build), it gets a certificate
bundle.

1 files changed, 4 insertions, 3 deletions

diff --git a/src/libstore/download.cc b/src/libstore/download.cc
index 63e498f060..33ab1f0278 100644
--- a/src/libstore/download.cc
+++ b/src/libstore/download.cc
@@ -221,9 +221,10 @@ struct CurlDownloader : public Downloader
             if (request.head)
                 curl_easy_setopt(req, CURLOPT_NOBODY, 1);
 
-            if (request.verifyTLS)
-                curl_easy_setopt(req, CURLOPT_CAINFO, settings.caFile.c_str());
-            else {
+            if (request.verifyTLS) {
+                if (settings.caFile != "")
+                    curl_easy_setopt(req, CURLOPT_CAINFO, settings.caFile.c_str());
+            } else {
                 curl_easy_setopt(req, CURLOPT_SSL_VERIFYPEER, 0);
                 curl_easy_setopt(req, CURLOPT_SSL_VERIFYHOST, 0);
             }