Add basic edit ldap auth test & actually fix #16252 (#16465)

One of the reasons why #16447 was needed and why #16268 was needed in
the first place was because it appears that editing ldap configuration
doesn't get tested.

This PR therefore adds a basic test that will run the edit pipeline.

In doing so it's now clear that #16447 and #16268 aren't actually
solving #16252. It turns out that what actually happens is that is that
the bytes are actually double encoded.

This PR now changes the json unmarshal wrapper to handle this double
encode.

Fix #16252

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: 6543 <6543@obermui.de>

2 files changed, 33 insertions, 13 deletions

diff --git a/models/login_source.go b/models/login_source.go
index bbd605bb41..5674196e0c 100644
--- a/models/login_source.go
+++ b/models/login_source.go
@@ -7,6 +7,7 @@ package models
 
 import (
 	"crypto/tls"
+	"encoding/binary"
 	"errors"
 	"fmt"
 	"net/smtp"
@@ -70,11 +71,30 @@ var (
 	_ convert.Conversion = &SSPIConfig{}
 )
 
-// jsonUnmarshalIgnoreErroneousBOM - due to a bug in xorm (see https://gitea.com/xorm/xorm/pulls/1957) - it's
-// possible that a Blob may gain an unwanted prefix of 0xff 0xfe.
-func jsonUnmarshalIgnoreErroneousBOM(bs []byte, v interface{}) error {
+// jsonUnmarshalHandleDoubleEncode - due to a bug in xorm (see https://gitea.com/xorm/xorm/pulls/1957) - it's
+// possible that a Blob may be double encoded or gain an unwanted prefix of 0xff 0xfe.
+func jsonUnmarshalHandleDoubleEncode(bs []byte, v interface{}) error {
 	json := jsoniter.ConfigCompatibleWithStandardLibrary
 	err := json.Unmarshal(bs, v)
+	if err != nil {
+		ok := true
+		rs := []byte{}
+		temp := make([]byte, 2)
+		for _, rn := range string(bs) {
+			if rn > 0xffff {
+				ok = false
+				break
+			}
+			binary.LittleEndian.PutUint16(temp, uint16(rn))
+			rs = append(rs, temp...)
+		}
+		if ok {
+			if rs[0] == 0xff && rs[1] == 0xfe {
+				rs = rs[2:]
+			}
+			err = json.Unmarshal(rs, v)
+		}
+	}
 	if err != nil && len(bs) > 2 && bs[0] == 0xff && bs[1] == 0xfe {
 		err = json.Unmarshal(bs[2:], v)
 	}
@@ -88,7 +108,7 @@ type LDAPConfig struct {
 
 // FromDB fills up a LDAPConfig from serialized format.
 func (cfg *LDAPConfig) FromDB(bs []byte) error {
-	err := jsonUnmarshalIgnoreErroneousBOM(bs, &cfg)
+	err := jsonUnmarshalHandleDoubleEncode(bs, &cfg)
 	if err != nil {
 		return err
 	}
@@ -129,7 +149,7 @@ type SMTPConfig struct {
 
 // FromDB fills up an SMTPConfig from serialized format.
 func (cfg *SMTPConfig) FromDB(bs []byte) error {
-	return jsonUnmarshalIgnoreErroneousBOM(bs, cfg)
+	return jsonUnmarshalHandleDoubleEncode(bs, cfg)
 }
 
 // ToDB exports an SMTPConfig to a serialized format.
@@ -146,7 +166,7 @@ type PAMConfig struct {
 
 // FromDB fills up a PAMConfig from serialized format.
 func (cfg *PAMConfig) FromDB(bs []byte) error {
-	return jsonUnmarshalIgnoreErroneousBOM(bs, cfg)
+	return jsonUnmarshalHandleDoubleEncode(bs, cfg)
 }
 
 // ToDB exports a PAMConfig to a serialized format.
@@ -167,7 +187,7 @@ type OAuth2Config struct {
 
 // FromDB fills up an OAuth2Config from serialized format.
 func (cfg *OAuth2Config) FromDB(bs []byte) error {
-	return jsonUnmarshalIgnoreErroneousBOM(bs, cfg)
+	return jsonUnmarshalHandleDoubleEncode(bs, cfg)
 }
 
 // ToDB exports an SMTPConfig to a serialized format.
@@ -187,7 +207,7 @@ type SSPIConfig struct {
 
 // FromDB fills up an SSPIConfig from serialized format.
 func (cfg *SSPIConfig) FromDB(bs []byte) error {
-	return jsonUnmarshalIgnoreErroneousBOM(bs, cfg)
+	return jsonUnmarshalHandleDoubleEncode(bs, cfg)
 }
 
 // ToDB exports an SSPIConfig to a serialized format.
diff --git a/models/repo_unit.go b/models/repo_unit.go
index a12e056a7d..f430e4f7f3 100644
--- a/models/repo_unit.go
+++ b/models/repo_unit.go
@@ -28,7 +28,7 @@ type UnitConfig struct{}
 
 // FromDB fills up a UnitConfig from serialized format.
 func (cfg *UnitConfig) FromDB(bs []byte) error {
-	return jsonUnmarshalIgnoreErroneousBOM(bs, &cfg)
+	return jsonUnmarshalHandleDoubleEncode(bs, &cfg)
 }
 
 // ToDB exports a UnitConfig to a serialized format.
@@ -44,7 +44,7 @@ type ExternalWikiConfig struct {
 
 // FromDB fills up a ExternalWikiConfig from serialized format.
 func (cfg *ExternalWikiConfig) FromDB(bs []byte) error {
-	return jsonUnmarshalIgnoreErroneousBOM(bs, &cfg)
+	return jsonUnmarshalHandleDoubleEncode(bs, &cfg)
 }
 
 // ToDB exports a ExternalWikiConfig to a serialized format.
@@ -62,7 +62,7 @@ type ExternalTrackerConfig struct {
 
 // FromDB fills up a ExternalTrackerConfig from serialized format.
 func (cfg *ExternalTrackerConfig) FromDB(bs []byte) error {
-	return jsonUnmarshalIgnoreErroneousBOM(bs, &cfg)
+	return jsonUnmarshalHandleDoubleEncode(bs, &cfg)
 }
 
 // ToDB exports a ExternalTrackerConfig to a serialized format.
@@ -80,7 +80,7 @@ type IssuesConfig struct {
 
 // FromDB fills up a IssuesConfig from serialized format.
 func (cfg *IssuesConfig) FromDB(bs []byte) error {
-	return jsonUnmarshalIgnoreErroneousBOM(bs, &cfg)
+	return jsonUnmarshalHandleDoubleEncode(bs, &cfg)
 }
 
 // ToDB exports a IssuesConfig to a serialized format.
@@ -104,7 +104,7 @@ type PullRequestsConfig struct {
 
 // FromDB fills up a PullRequestsConfig from serialized format.
 func (cfg *PullRequestsConfig) FromDB(bs []byte) error {
-	return jsonUnmarshalIgnoreErroneousBOM(bs, &cfg)
+	return jsonUnmarshalHandleDoubleEncode(bs, &cfg)
 }
 
 // ToDB exports a PullRequestsConfig to a serialized format.