Error if updateKeyValueStream tries to set a unsupported config

The updateKeyValueStream has a concept of the known configuration options (via allConfig). If the user tries to modify a config option that is not part of "allConfig" error. 

4 files changed, 22 insertions, 11 deletions

diff --git a/corecfg/picfg_test.go b/corecfg/picfg_test.go
index 5689c1e79a..4ca3e13263 100644
--- a/corecfg/picfg_test.go
+++ b/corecfg/picfg_test.go
@@ -43,9 +43,7 @@ var _ = Suite(&piCfgSuite{})
 var mockConfigTxt = `
 # For more options and information see
 # http://www.raspberrypi.org/documentation/configuration/config-txt.md
-# Some settings may impact device functionality. See link above for details
-# uncomment if you get no picture on HDMI for a default "safe" mode
-#hdmi_safe=1
+#hdmi_group=1
 # uncomment this if your display has a black border of unused pixels visible
 # and your display can output without overscan
 #disable_overscan=1
@@ -115,7 +113,7 @@ func (s *piCfgSuite) TestConfigurePiConfigNoChangeUnset(c *C) {
	c.Assert(err, IsNil)
	defer os.Chmod(filepath.Dir(s.mockConfigPath), 0755)
 
-	err = corecfg.UpdatePiConfig(s.mockConfigPath, map[string]string{"hdmi_safe": ""})
+	err = corecfg.UpdatePiConfig(s.mockConfigPath, map[string]string{"hdmi_group": ""})
	c.Assert(err, IsNil)
 }
 
@@ -126,8 +124,8 @@ func (s *piCfgSuite) TestConfigurePiConfigNoChangeSet(c *C) {
	c.Assert(err, IsNil)
	defer os.Chmod(filepath.Dir(s.mockConfigPath), 0755)
 
-	err = corecfg.UpdatePiConfig(s.mockConfigPath, map[string]string{"unrelated_options": "are-kept"})
-	c.Assert(err, IsNil)
+	err = corecfg.UpdatePiConfig(s.mockConfigPath, map[string]string{"unrelated_options": "cannot-be-set"})
+	c.Assert(err, ErrorMatches, `cannot set unsupported configuration value "unrelated_options"`)
 }
 
 func (s *piCfgSuite) TestConfigurePiConfigIntegration(c *C) {
diff --git a/corecfg/proxy.go b/corecfg/proxy.go
index af84976686..a9123cd566 100644
--- a/corecfg/proxy.go
+++ b/corecfg/proxy.go
@@ -29,9 +29,9 @@ import (
 )
 
 var proxyConfigKeys = map[string]bool{
-	"http": true,
-	"https": true,
-	"ftp": true,
+	"http_proxy": true,
+	"https_proxy": true,
+	"ftp_proxy": true,
 }
 
 func etcEnvironment() string {
diff --git a/corecfg/utils.go b/corecfg/utils.go
index fb1758365a..f6018b75b9 100644
--- a/corecfg/utils.go
+++ b/corecfg/utils.go
@@ -37,10 +37,12 @@ var rx = regexp.MustCompile(`^[ \t]*(#?)[ \t#]*([a-z_]+)=(.*)$`)
 // the "config" input is applied. If changes need to be written a []string
 // that contains the full file is returned. On error an error is returned.
 func updateKeyValueStream(r io.Reader, allConfig map[string]bool, newConfig map[string]string) (toWrite []string, err error) {
-	// build regexp
	cfgKeys := make([]string, len(newConfig))
	i := 0
	for k := range newConfig {
+	if !allConfig[k] {
+	return nil, fmt.Errorf("cannot set unsupported configuration value %q", k)
+	}
	cfgKeys[i] = k
	i++
	}
diff --git a/corecfg/utils_test.go b/corecfg/utils_test.go
index 578225e1a5..e13a8eaf0f 100644
--- a/corecfg/utils_test.go
+++ b/corecfg/utils_test.go
@@ -31,7 +31,7 @@ type utilsSuite struct{}
 
 var _ = Suite(&utilsSuite{})
 
-func (s *utilsSuite) TestUpdateKeyValueStreamNoChanges(c *C) {
+func (s *utilsSuite) TestUpdateKeyValueStreamNoNewConfig(c *C) {
	in := bytes.NewBufferString("foo=bar")
	newConfig := map[string]string{}
	allConfig := map[string]bool{}
@@ -41,6 +41,17 @@ func (s *utilsSuite) TestUpdateKeyValueStreamNoChanges(c *C) {
	c.Check(toWrite, IsNil)
 }
 
+func (s *utilsSuite) TestUpdateKeyValueStreamConfigNotInAllConfig(c *C) {
+	in := bytes.NewBufferString("")
+	newConfig := map[string]string{"unsupported-options": "cannot be set"}
+	allConfig := map[string]bool{
+	"foo": true,
+	}
+
+	_, err := corecfg.UpdateKeyValueStream(in, allConfig, newConfig)
+	c.Check(err, ErrorMatches, `cannot set unsupported configuration value \"unsupported-options"`)
+}
+
 func (s *utilsSuite) TestUpdateKeyValueStreamOneChange(c *C) {
	in := bytes.NewBufferString("foo=bar")
	newConfig := map[string]string{"foo": "baz"}