hrev52827 adds 1 changeset to branch 'master'
old head: f7e239170263e2ce35e3c73fcc417601f6748b5f
new head: 5186fb7ebd21404e6c3c373d4fb271aa8195e242
overview:
https://git.haiku-os.org/haiku/log/?qt=range&q=5186fb7ebd21+%5Ef7e239170263
----------------------------------------------------------------------------
5186fb7ebd21: Network: Avoid DHCP over-writing user specified DNS settings
* Adds parser to servers/net/nethost, to check current
settings in resolv.conf before updating
If user has specified DNS settings manually, DHCP derived
settings are appended to resolv.conf, rather than overwriting.
(If no user specified data is present, or in the event of
a badly damaged resolv.conf, DHCP over-writes file in same
manner as prior to this change)
Fixes #11565.
Change-Id: I43464909009d2416d57f66f7bd14d13c81f803e7
Reviewed-on: https://review.haiku-os.org/c/997
Reviewed-by: Axel Dörfler <axeld@xxxxxxxxxxxxxxxx>
Reviewed-by: Stephan Aßmus <superstippi@xxxxxx>
[ Rob Gill <rrobgill@xxxxxxxxxxxxxx> ]
----------------------------------------------------------------------------
Revision: hrev52827
Commit: 5186fb7ebd21404e6c3c373d4fb271aa8195e242
URL: https://git.haiku-os.org/haiku/commit/?id=5186fb7ebd21
Author: Rob Gill <rrobgill@xxxxxxxxxxxxxx>
Date: Thu Jan 31 07:12:50 2019 UTC
Committer: Stephan Aßmus <superstippi@xxxxxx>
Commit-Date: Fri Feb 1 08:59:48 2019 UTC
Ticket: https://dev.haiku-os.org/ticket/11565
----------------------------------------------------------------------------
2 files changed, 60 insertions(+), 15 deletions(-)
.../dnsclient/DNSSettingsView.cpp | 4 +-
src/servers/net/NetServer.cpp | 71 ++++++++++++++++----
----------------------------------------------------------------------------
diff --git a/src/add-ons/network_settings/dnsclient/DNSSettingsView.cpp
b/src/add-ons/network_settings/dnsclient/DNSSettingsView.cpp
index 131ec34552..0e91851fb4 100644
--- a/src/add-ons/network_settings/dnsclient/DNSSettingsView.cpp
+++ b/src/add-ons/network_settings/dnsclient/DNSSettingsView.cpp
@@ -233,7 +233,7 @@ DNSSettingsView::_SaveDNSConfiguration()
return file.InitCheck();
}
- BString content("# Generated by Network preferences\n");
+ BString content("# Static DNS entries\n# Generated by Network
preferences\n");
for (int i = 0; i < fServerListView->CountItems(); i++) {
BString item =
((BStringItem*)fServerListView->ItemAt(i))->Text();
@@ -244,5 +244,7 @@ DNSSettingsView::_SaveDNSConfiguration()
if (strlen(fDomain->Text()) > 0)
content << "domain\t" << fDomain->Text() << "\n";
+ content << "# Dynamic DNS entries\n# may be altered by DHCP\n";
+
return file.Write(content.String(), content.Length());
}
diff --git a/src/servers/net/NetServer.cpp b/src/servers/net/NetServer.cpp
index 75893933b6..90ffe4fe47 100644
--- a/src/servers/net/NetServer.cpp
+++ b/src/servers/net/NetServer.cpp
@@ -598,30 +598,73 @@ NetServer::_ConfigureInterface(BMessage& message)
status_t
NetServer::_ConfigureResolver(BMessage& resolverConfiguration)
{
- // TODO: resolv.conf should be parsed, all information should be
- // maintained and it should be distinguished between user entered
- // and auto-generated parts of the file, with this method only
re-writing
- // the auto-generated parts of course.
+ // Store resolver settings in resolv.conf file, while maintaining any
+ // user specified settings already present.
BPath path;
if (find_directory(B_SYSTEM_SETTINGS_DIRECTORY, &path) != B_OK
|| path.Append("network/resolv.conf") != B_OK)
return B_ERROR;
- FILE* file = fopen(path.Path(), "w");
- if (file != NULL) {
- const char* nameserver;
- for (int32 i = 0;
resolverConfiguration.FindString("nameserver", i,
- &nameserver) == B_OK; i++) {
- fprintf(file, "nameserver %s\n", nameserver);
+ FILE* file = fopen(path.Path(), "r+");
+ // open existing resolv.conf if possible
+ if (file == NULL) {
+ // no existing resolv.conf, create a new one
+ file = fopen(path.Path(), "w");
+ if (file == NULL) {
+ fprintf(stderr, "Could not open resolv.conf: %s\n",
+ strerror(errno));
+ return errno;
}
+ } else {
+ // An existing resolv.conf was found, parse it for user settings
+ const char* staticDNS = "# Static DNS Only";
+ size_t sizeStaticDNS = strlen(staticDNS);
+ const char* dynamicDNS = "# Dynamic DNS entries";
+ size_t sizeDynamicDNS = strlen(dynamicDNS);
+ char resolveConfBuffer[80];
+ size_t sizeResolveConfBuffer = sizeof(resolveConfBuffer);
+
+ while (fgets(resolveConfBuffer, sizeResolveConfBuffer, file)) {
+ if (strncmp(resolveConfBuffer, staticDNS,
sizeStaticDNS) == 0) {
+ // If DNS is set to static only, don't modify
+ fclose(file);
+ return B_OK;
+ } else if (strncmp(resolveConfBuffer, dynamicDNS,
sizeDynamicDNS)
+ == 0) {
+ // Overwrite existing dynamic entries
+ break;
+ }
+ }
+
+ if (feof(file) != 0) {
+ // No static entries found, close and re-open as new
file
+ fclose(file);
+ file = fopen(path.Path(), "w");
+ if (file == NULL) {
+ fprintf(stderr, "Could not open resolv.conf:
%s\n",
+ strerror(errno));
+ return errno;
+ }
+ }
+ }
- const char* domain;
- if (resolverConfiguration.FindString("domain", &domain) == B_OK)
- fprintf(file, "domain %s\n", domain);
+ fprintf(file, "# Added automatically by DHCP\n");
- fclose(file);
+ const char* nameserver;
+ for (int32 i = 0; resolverConfiguration.FindString("nameserver", i,
+ &nameserver) == B_OK; i++) {
+ fprintf(file, "nameserver %s\n", nameserver);
}
+
+ const char* domain;
+ if (resolverConfiguration.FindString("domain", &domain) == B_OK)
+ fprintf(file, "domain %s\n", domain);
+
+ fprintf(file, "# End of automatic DHCP additions\n");
+
+ fclose(file);
+
return B_OK;
}
