From f68f6c9b37cea1f33cb6fa791e6678b9df3a237b Mon Sep 17 00:00:00 2001
From: Ainar Garipov <a.garipov@adguard.com>
Date: Mon, 15 Feb 2021 19:07:08 +0300
Subject: [PATCH] Pull request: all: fix statip ip ck
Merge in DNS/adguard-home from fix-static-ip-check to master
Squashed commit of the following:
commit af365c106f3d620afc77492a06f5368611328f5f
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date: Mon Feb 15 18:55:35 2021 +0300
all: doc changes
commit 922afb262458fc488e03cad232430d90c504f2f3
Merge: 43fec5fb dbcc55f5
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date: Mon Feb 15 18:53:31 2021 +0300
Merge branch 'master' into fix-static-ip-check
commit 43fec5fb79f5c67b375da00aa73d11b3ed9ba3a4
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date: Mon Feb 15 18:37:16 2021 +0300
all: fix statip ip ck
---
CHANGELOG.md | 2 ++
internal/dhcpd/http.go | 32 +++++++++++++++++++++++---------
internal/sysutil/net.go | 7 +++++++
internal/sysutil/net_linux.go | 17 +++++++++++++----
4 files changed, 45 insertions(+), 13 deletions(-)
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 127971a1..39217416 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -31,6 +31,8 @@ and this project adheres to
### Fixed
+- Error when enabling the DHCP server when AdGuard Home couldn't determine if
+ the machine has a static IP.
- Optical issue on custom rules ([#2641]).
- Occasional crashes during startup.
- The field `"range_start"` in the `GET /control/dhcp/status` HTTP API response
diff --git a/internal/dhcpd/http.go b/internal/dhcpd/http.go
index de155c5c..2dab1132 100644
--- a/internal/dhcpd/http.go
+++ b/internal/dhcpd/http.go
@@ -95,26 +95,40 @@ func (s *Server) enableDHCP(ifaceName string) (code int, err error) {
var hasStaticIP bool
hasStaticIP, err = sysutil.IfaceHasStaticIP(ifaceName)
if err != nil {
- // ErrPermission may happen here on Linux systems where AdGuard
- // Home is installed using Snap. That doesn't necessarily mean
- // that the machine doesn't have a static IP, so we can assume
- // that it has and go on. If the machine doesn't, we'll get an
- // error later.
- //
- // See https://github.com/AdguardTeam/AdGuardHome/issues/2667.
if errors.Is(err, os.ErrPermission) {
+ // ErrPermission may happen here on Linux systems where
+ // AdGuard Home is installed using Snap. That doesn't
+ // necessarily mean that the machine doesn't have
+ // a static IP, so we can assume that it has and go on.
+ // If the machine doesn't, we'll get an error later.
+ //
+ // See https://github.com/AdguardTeam/AdGuardHome/issues/2667.
+ //
+ // TODO(a.garipov): I was thinking about moving this
+ // into IfaceHasStaticIP, but then we wouldn't be able
+ // to log it. Think about it more.
log.Info("error while checking static ip: %s; "+
"assuming machine has static ip and going on", err)
hasStaticIP = true
+ } else if errors.Is(err, sysutil.ErrNoStaticIPInfo) {
+ // Couldn't obtain a definitive answer. Assume static
+ // IP an go on.
+ log.Info("can't check for static ip; " +
+ "assuming machine has static ip and going on")
+ hasStaticIP = true
} else {
- return http.StatusInternalServerError, fmt.Errorf("checking static ip: %w", err)
+ err = fmt.Errorf("checking static ip: %w", err)
+
+ return http.StatusInternalServerError, err
}
}
if !hasStaticIP {
err = sysutil.IfaceSetStaticIP(ifaceName)
if err != nil {
- return http.StatusInternalServerError, fmt.Errorf("setting static ip: %w", err)
+ err = fmt.Errorf("setting static ip: %w", err)
+
+ return http.StatusInternalServerError, err
}
}
diff --git a/internal/sysutil/net.go b/internal/sysutil/net.go
index 0e3b448e..9ba41704 100644
--- a/internal/sysutil/net.go
+++ b/internal/sysutil/net.go
@@ -5,10 +5,17 @@ import (
"os/exec"
"strings"
+ "github.com/AdguardTeam/AdGuardHome/internal/agherr"
"github.com/AdguardTeam/golibs/log"
)
+// ErrNoStaticIPInfo is returned by IfaceHasStaticIP when no information about
+// the IP being static is available.
+const ErrNoStaticIPInfo agherr.Error = "no information about static ip"
+
// IfaceHasStaticIP checks if interface is configured to have static IP address.
+// If it can't give a definitive answer, it returns false and an error for which
+// errors.Is(err, ErrNoStaticIPInfo) is true.
func IfaceHasStaticIP(ifaceName string) (has bool, err error) {
return ifaceHasStaticIP(ifaceName)
}
diff --git a/internal/sysutil/net_linux.go b/internal/sysutil/net_linux.go
index 9205fd5c..1964f9dd 100644
--- a/internal/sysutil/net_linux.go
+++ b/internal/sysutil/net_linux.go
@@ -21,7 +21,11 @@ import (
const maxConfigFileSize = 1024 * 1024
func ifaceHasStaticIP(ifaceName string) (has bool, err error) {
- var f *os.File
+ // TODO(a.garipov): Currently, this function returns the first
+ // definitive result. So if /etc/dhcpcd.conf has a static IP while
+ // /etc/network/interfaces doesn't, it will return true. Perhaps this
+ // is not the most desirable behavior.
+
for _, check := range []struct {
checker func(io.Reader, string) (bool, error)
filePath string
@@ -32,8 +36,11 @@ func ifaceHasStaticIP(ifaceName string) (has bool, err error) {
checker: ifacesStaticConfig,
filePath: "/etc/network/interfaces",
}} {
+ var f *os.File
f, err = os.Open(check.filePath)
if err != nil {
+ // ErrNotExist can happen here if there is no such file.
+ // This is normal, as not every system uses those files.
if errors.Is(err, os.ErrNotExist) {
err = nil
@@ -52,12 +59,14 @@ func ifaceHasStaticIP(ifaceName string) (has bool, err error) {
defer fileReadCloser.Close()
has, err = check.checker(fileReadCloser, ifaceName)
- if has || err != nil {
- break
+ if err != nil {
+ return false, err
}
+
+ return has, nil
}
- return has, err
+ return false, ErrNoStaticIPInfo
}
// dhcpcdStaticConfig checks if interface is configured by /etc/dhcpcd.conf to