Merge pull request #8062 from edolstra/ssl-cert-file

Add a setting for configuring the SSL certificates file

3 files changed, 29 insertions, 11 deletions

diff --git a/src/libstore/filetransfer.cc b/src/libstore/filetransfer.cc
index b5fe7c03b..1ba399a29 100644
--- a/src/libstore/filetransfer.cc
+++ b/src/libstore/filetransfer.cc
@@ -318,7 +318,7 @@ struct curlFileTransfer : public FileTransfer
 
             if (request.verifyTLS) {
                 if (settings.caFile != "")
-                    curl_easy_setopt(req, CURLOPT_CAINFO, settings.caFile.c_str());
+                    curl_easy_setopt(req, CURLOPT_CAINFO, settings.caFile.get().c_str());
             } else {
                 curl_easy_setopt(req, CURLOPT_SSL_VERIFYPEER, 0);
                 curl_easy_setopt(req, CURLOPT_SSL_VERIFYHOST, 0);
diff --git a/src/libstore/globals.cc b/src/libstore/globals.cc
index 8781e10ea..823b4af74 100644
--- a/src/libstore/globals.cc
+++ b/src/libstore/globals.cc
@@ -44,14 +44,9 @@ Settings::Settings()
     lockCPU = getEnv("NIX_AFFINITY_HACK") == "1";
     allowSymlinkedStore = getEnv("NIX_IGNORE_SYMLINK_STORE") == "1";
 
-    caFile = getEnv("NIX_SSL_CERT_FILE").value_or(getEnv("SSL_CERT_FILE").value_or(""));
-    if (caFile == "") {
-        for (auto & fn : {"/etc/ssl/certs/ca-certificates.crt", "/nix/var/nix/profiles/default/etc/ssl/certs/ca-bundle.crt"})
-            if (pathExists(fn)) {
-                caFile = fn;
-                break;
-            }
-    }
+    auto sslOverride = getEnv("NIX_SSL_CERT_FILE").value_or(getEnv("SSL_CERT_FILE").value_or(""));
+    if (sslOverride != "")
+        caFile = sslOverride;
 
     /* Backwards compatibility. */
     auto s = getEnv("NIX_REMOTE_SYSTEMS");
@@ -175,6 +170,13 @@ bool Settings::isWSL1()
     return hasSuffix(utsbuf.release, "-Microsoft");
 }
 
+Path Settings::getDefaultSSLCertFile()
+{
+    for (auto & fn : {"/etc/ssl/certs/ca-certificates.crt", "/nix/var/nix/profiles/default/etc/ssl/certs/ca-bundle.crt"})
+        if (pathExists(fn)) return fn;
+    return "";
+}
+
 const std::string nixVersion = PACKAGE_VERSION;
 
 NLOHMANN_JSON_SERIALIZE_ENUM(SandboxMode, {
diff --git a/src/libstore/globals.hh b/src/libstore/globals.hh
index db01ab657..09a58afed 100644
--- a/src/libstore/globals.hh
+++ b/src/libstore/globals.hh
@@ -63,6 +63,8 @@ class Settings : public Config {
 
     bool isWSL1();
 
+    Path getDefaultSSLCertFile();
+
 public:
 
     Settings();
@@ -825,8 +827,22 @@ public:
           > `.netrc`.
         )"};
 
-    /* Path to the SSL CA file used */
-    Path caFile;
+    Setting<Path> caFile{
+        this, getDefaultSSLCertFile(), "ssl-cert-file",
+        R"(
+          The path of a file containing CA certificates used to
+          authenticate `https://` downloads. Nix by default will use
+          the first of the following files that exists:
+
+          1. `/etc/ssl/certs/ca-certificates.crt`
+          2. `/nix/var/nix/profiles/default/etc/ssl/certs/ca-bundle.crt`
+
+          The path can be overridden by the following environment
+          variables, in order of precedence:
+
+          1. `NIX_SSL_CERT_FILE`
+          2. `SSL_CERT_FILE`
+        )"};
 
 #if __linux__
     Setting<bool> filterSyscalls{