1 files changed, 115 insertions, 0 deletions
diff --git a/crypto/pkcs11/utils.go b/crypto/pkcs11/utils.go
new file mode 100644
index 0000000..231da23
--- /dev/null
+++ b/crypto/pkcs11/utils.go
@@ -0,0 +1,115 @@
+/*
+   Copyright The ocicrypt Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package pkcs11
+
+import (
+	"fmt"
+	"os"
+	"runtime"
+	"strings"
+	"sync"
+)
+
+var (
+	envLock sync.Mutex
+)
+
+// setEnvVars sets the environment variables given in the map and locks the environment from
+// modification with the same function; if successful, you *must* call restoreEnv with the return
+// value from this function
+func setEnvVars(env map[string]string) ([]string, error) {
+	envLock.Lock()
+
+	if len(env) == 0 {
+		return nil, nil
+	}
+
+	oldenv := os.Environ()
+
+	for k, v := range env {
+		err := os.Setenv(k, v)
+		if err != nil {
+			restoreEnv(oldenv)
+			return nil, fmt.Errorf("Could not set environment variable '%s' to '%s': %w", k, v, err)
+		}
+	}
+
+	return oldenv, nil
+}
+
+func arrayToMap(elements []string) map[string]string {
+	o := make(map[string]string)
+
+	for _, element := range elements {
+		p := strings.SplitN(element, "=", 2)
+		if len(p) == 2 {
+			o[p[0]] = p[1]
+		}
+	}
+
+	return o
+}
+
+// restoreEnv restores the environment to be exactly as given in the array of strings
+// and unlocks the lock
+func restoreEnv(envs []string) {
+	if envs != nil && len(envs) >= 0 {
+		target := arrayToMap(envs)
+		curr := arrayToMap(os.Environ())
+
+		for nc, vc := range curr {
+			vt, ok := target[nc]
+			if !ok {
+				os.Unsetenv(nc)
+			} else if vc == vt {
+				delete(target, nc)
+			}
+		}
+
+		for nt, vt := range target {
+			os.Setenv(nt, vt)
+		}
+	}
+
+	envLock.Unlock()
+}
+
+func getHostAndOsType() (string, string, string) {
+	ht := ""
+	ot := ""
+	st := ""
+	switch runtime.GOOS {
+	case "linux":
+		ot = "linux"
+		st = "gnu"
+		switch runtime.GOARCH {
+		case "arm":
+			ht = "arm"
+		case "arm64":
+			ht = "aarch64"
+		case "amd64":
+			ht = "x86_64"
+		case "ppc64le":
+			ht = "powerpc64le"
+		case "riscv64":
+			ht = "riscv64"
+		case "s390x":
+			ht = "s390x"
+		}
+	}
+	return ht, ot, st
+}