qemu-vm: implement `virtualization.tpm.provisioning` (#364379)

nixos/modules/virtualisation/qemu-vm.nix

···
       ${lib.getExe cfg.tpm.package} \
         socket \
         --tpmstate dir="$NIX_SWTPM_DIR" \
-        --ctrl type=unixio,path="$NIX_SWTPM_DIR"/socket,terminate \
+        --server type=unixio,path="$NIX_SWTPM_DIR"/socket \
+        --ctrl type=unixio,path="$NIX_SWTPM_DIR"/socket.ctrl \
         --pid file="$NIX_SWTPM_DIR"/pid --daemon \
+        --flags not-need-init \
         --tpm2 \
         --log file="$NIX_SWTPM_DIR"/stdout,level=6
 
+      (
+        export TPM2TOOLS_TCTI=swtpm:path="$NIX_SWTPM_DIR"/socket
+        export PATH=${
+          lib.makeBinPath [
+            pkgs.tpm2-tools
+          ]
+        }:$PATH
+
+        tpm2_startup --clear
+        tpm2_startup
+
+        ${lib.optionalString (cfg.tpm.provisioning != null)
+          # Run provisioning in a subshell not to pollute vars
+          ''
+            (
+              export TCTI=swtpm:path="$NIX_SWTPM_DIR"/socket
+              ${cfg.tpm.provisioning}
+            )
+          ''
+        }
+
+        tpm2_shutdown
+        tpm2_shutdown --clear
+      )
+
       # Enable `fdflags` builtin in Bash
       # We will need it to perform surgical modification of the file descriptor
       # passed in the coprocess to remove `FD_CLOEXEC`, i.e. close the file descriptor
···
       # will stop it.
       coproc waitingswtpm {
         read || :
-        echo "" | ${lib.getExe hostPkgs.socat} STDIO UNIX-CONNECT:"$NIX_SWTPM_DIR"/socket
+        ${cfg.tpm.package}/bin/swtpm_ioctl --unix "$NIX_SWTPM_DIR"/socket.ctrl --stop 2>/dev/null
       }
       # Clear `FD_CLOEXEC` on the coprocess' file descriptor stdin.
       fdflags -s-cloexec ''${waitingswtpm[1]}
···
         example = "tpm-tis-device";
         description = "QEMU device model for the TPM, uses the appropriate default based on th guest platform system and the package passed.";
       };
+
+      provisioning = mkOption {
+        type = types.nullOr types.str;
+        default = null;
+        description = ''
+          Script to provision the TPM before control is handed off to the VM.
+
+          `TPM2TOOLS_TCTI` will be provided to configure tpm2-tools to use the
+          swtpm instance transparently.
+          `TCTI` is also provided as a generic value, consumer is expected to
+          re-export it however it may need (`TPM2OPENSSL_TCTI`, `TPM2_PKCS11_TCTI`,
+          ...).
+        '';
+        example = literalExpression ''
+          tpm2_nvdefine 0xcafecafe \
+            -C o \
+            -a "ownerread|policyread|policywrite|ownerwrite|authread|authwrite"
+          echo "foobar" | tpm2_nvwrite 0xcafecafe -C o
+        '';
+      };
     };
 
     virtualisation.useDefaultFilesystems = mkOption {
···
         "-nographic"
       ])
       (mkIf (cfg.tpm.enable) [
-        "-chardev socket,id=chrtpm,path=\"$NIX_SWTPM_DIR\"/socket"
+        "-chardev socket,id=chrtpm,path=\"$NIX_SWTPM_DIR\"/socket.ctrl"
         "-tpmdev emulator,id=tpm_dev_0,chardev=chrtpm"
         "-device ${cfg.tpm.deviceModel},tpmdev=tpm_dev_0"
       ])

nixos/tests/all-tests.nix

···
   tmate-ssh-server = handleTest ./tmate-ssh-server.nix { };
   tomcat = handleTest ./tomcat.nix {};
   tor = handleTest ./tor.nix {};
+  tpm-ek = handleTest ./tpm-ek {};
   traefik = handleTestOn ["aarch64-linux" "x86_64-linux"] ./traefik.nix {};
   trafficserver = handleTest ./trafficserver.nix {};
   transfer-sh = handleTest ./transfer-sh.nix {};

nixos/tests/tpm-ek/ca.crt

···
+-----BEGIN CERTIFICATE-----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+ePqAEvMSMocB2OJSZWm+2IXZe3M+ecc3fYPlCRMACghsof9RKwHGt9gyrbL70GBL
+7ikJrJRoZ2JGva3AVvLj+bJts1c5j8jpZWK3dCrmJhevzO7agMweJUrj/7oPqqhH
+L+VJmfXYK1S25cTei3BsD72gX/DhB0jwKo0Raaj5gO6wR01eR7JPS/E+3lthT8fC
+BktxCN5RlMBiNiNfrmHNgg7FZ3ONsi6CIArNFj/wbTM/ic0MSXmkEyskY2NSzSWv
+yJ6Z77Zh7MpVkmGsm4hyFzZ2cnTotGoFCd/AGfmj+GlW
+-----END CERTIFICATE-----

nixos/tests/tpm-ek/ca.priv

···
+-----BEGIN PRIVATE KEY-----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+NDhm1LMkQyt5dlQYux8ZFOG4xezgR15cEZkWOhmkvK0QS0VGzalHZqgKkZXvafJW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+-----END PRIVATE KEY-----

nixos/tests/tpm-ek/default.nix

···
+import ../make-test-python.nix (
+  { lib, pkgs, ... }:
+
+  let
+    inherit (pkgs) writeText tpm2-tools openssl;
+    ek_config = writeText "ek-sign.cnf" ''
+      [ tpm_policy ]
+      basicConstraints = CA:FALSE
+
+      keyUsage = keyEncipherment
+      certificatePolicies = 2.23.133.2.1
+      extendedKeyUsage = 2.23.133.8.1
+
+      subjectAltName = ASN1:SEQUENCE:dirname_tpm
+
+      [ dirname_tpm ]
+      seq = EXPLICIT:4,SEQUENCE:dirname_tpm_seq
+
+      [ dirname_tpm_seq ]
+      set = SET:dirname_tpm_set
+
+      [ dirname_tpm_set ]
+      seq.1 = SEQUENCE:dirname_tpm_seq_manufacturer
+      seq.2 = SEQUENCE:dirname_tpm_seq_model
+      seq.3 = SEQUENCE:dirname_tpm_seq_version
+
+      # We're going to mock up an STM TPM here
+      [dirname_tpm_seq_manufacturer]
+      oid = OID:2.23.133.2.1
+      str = UTF8:"id:53544D20"
+
+      [dirname_tpm_seq_model]
+      oid = OID:2.23.133.2.2
+      str = UTF8:"ST33HTPHAHD4
+
+      [dirname_tpm_seq_version]
+      oid = OID:2.23.133.2.3
+      str = UTF8:"id:00010101"
+    '';
+  in
+  {
+    name = "tpm-ek";
+
+    meta = {
+      maintainers = with lib.maintainers; [ baloo ];
+    };
+
+    nodes.machine =
+      { pkgs, ... }:
+      {
+        environment.systemPackages = [
+          openssl
+          tpm2-tools
+        ];
+
+        security.tpm2 = {
+          enable = true;
+          tctiEnvironment.enable = true;
+        };
+
+        virtualisation.tpm = {
+          enable = true;
+          provisioning = ''
+            export PATH=${
+              lib.makeBinPath [
+                openssl
+              ]
+            }:$PATH
+
+            tpm2_createek -G rsa -u ek.pub -c ek.ctx -f pem
+
+            # Sign a certificate
+            # Pretend we're an STM TPM
+            openssl x509 \
+              -extfile ${ek_config} \
+              -new -days 365 \
+              \
+              -subj "/CN=this.is.required.but.it.should.not/" \
+              -extensions tpm_policy \
+              \
+              -CA ${./ca.crt} -CAkey ${./ca.priv} \
+              \
+              -out device.der -outform der \
+              -force_pubkey ek.pub
+
+            # Create a nvram slot for the certificate, and we need the size
+            # to precisely match the length of the certificate we're going to
+            # put in.
+            tpm2_nvdefine 0x01c00002 \
+              -C o \
+              -a "ownerread|policyread|policywrite|ownerwrite|authread|authwrite" \
+              -s "$(wc -c device.der| cut -f 1 -d ' ')"
+
+            tpm2_nvwrite 0x01c00002 -C o -i device.der
+          '';
+        };
+      };
+
+    testScript = ''
+      start_all()
+      machine.wait_for_unit("multi-user.target")
+
+      machine.succeed('tpm2_nvread 0x01c00002 | openssl x509 -inform der -out /tmp/ek.pem')
+      print(machine.succeed('openssl x509 -in /tmp/ek.pem -text'))
+      machine.succeed('openssl verify -CAfile ${./ca.crt} /tmp/ek.pem')
+    '';
+  }
+)