1 files changed, 71 insertions, 0 deletions
diff --git a/pem.go b/pem.go
new file mode 100644
index 0000000..d3956f6
--- /dev/null
+++ b/pem.go
@@ -0,0 +1,71 @@
+package main
+
+// handle the pem decoding of files
+
+import (
+	"encoding/pem"
+	"fmt"
+	"io"
+	"io/ioutil"
+
+	"github.com/gibheer/pki"
+)
+
+type (
+	pemMap map[string][][]byte
+)
+
+// Return the content of a section from the pem part.
+//
+// To get this working, the section must only be contained one time and nothing
+// but the wanted section must exist.
+func getSectionFromPem(pems pemMap, label string) ([]byte, error) {
+	if len(pems) > 1 {
+		return []byte{}, fmt.Errorf("too many entries in sign request file")
+	}
+	if len(pems[label]) > 1 {
+		return []byte{}, fmt.Errorf("too many sign requests found in file")
+	}
+	return pems[label][0], nil
+}
+
+// parse the content of a file into a map of pem decoded bodies
+func parseFile(file io.Reader) (pemMap, error) {
+	raw, err := ioutil.ReadAll(file)
+	if err != nil {
+		return nil, err
+	}
+	return parsePem(raw)
+}
+
+// parse a pem encoded payload into a lookup map
+//
+// Returns a map of labels and content and the overall number of found items.
+func parsePem(payload []byte) (pemMap, error) {
+	res := pemMap{}
+	rest := payload
+	rest_len := len(rest)
+	for len(rest) > 0 {
+		var block *pem.Block
+		block, rest = pem.Decode(rest)
+		if block == nil && len(rest) == rest_len {
+			return nil, fmt.Errorf("no pem encoding found")
+		}
+		res[block.Type] = append(res[block.Type], block.Bytes)
+		rest_len = len(rest)
+	}
+	return res, nil
+}
+
+func writePem(o pki.Pemmer, w io.Writer) error {
+	marsh_pem, err := o.MarshalPem()
+	if err != nil {
+		return err
+	}
+
+	_, err = marsh_pem.WriteTo(w)
+	if err != nil {
+		return err
+	}
+	return nil
+}