tset (9ce54615) · Commits · jan.koester / fresh

commands/network/ip.cpp

+255 −10

Changes for commands/network/ip.cpp: 255 added lines, 10 removed lines.
Original line number	Diff line number	Diff line
		@@ -34,11 +34,15 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
		// getifaddrs() for address enumeration, and /proc/net/route + /proc/net/arp
		// for the read side of routes/neighbours. That covers every common `ip`
		// invocation (link/addr/route/neigh show, link set up/down, addr add/del,
		// route add/del) without needing netlink at all. Toybox itself never had an
		// `ip` applet (only the older ifconfig/route) - this exists to replace that
		// pairing with the modern single command, not to be a complete iproute2
		// clone (no policy routing, no multiple routing tables, no tunnels/bridges/
		// VLANs, IPv6 route add/del is show-only).
		// route add/del) without needing netlink at all. Bridges and bonds can be
		// created, deleted and given ports the same way: bridges with brctl's
		// ioctls (SIOCBRADDBR/SIOCBRDELBR/SIOCBRADDIF/SIOCBRDELIF), bonds through
		// /sys/class/net/bonding_masters and <bond>/bonding/slaves. Link types that
		// only netlink can make (veth, dummy, vlan, ...) are refused with an error.
		// Toybox itself never had an `ip` applet (only the older ifconfig/route) -
		// this exists to replace that pairing with the modern single command, not
		// to be a complete iproute2 clone (no policy routing, no multiple routing
		// tables, no tunnels/VLANs, IPv6 route add/del is show-only).

		#include <iostream>
		#include <sstream>
		@@ -49,8 +53,11 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
		#include <cstdio>
		#include <cerrno>

		#include <fcntl.h>
		#include <unistd.h>
		#include <sys/socket.h>
		#include <sys/stat.h>
		#include <linux/sockios.h>
		#include <sys/ioctl.h>
		#include <net/if.h>
		#include <net/route.h>
		@@ -70,6 +77,10 @@ namespace fresh { namespace cmd {
		std::cout <<
		"usage: ip link show [DEV]\n"
		" ip link set DEV up\|down\n"
		" ip link set DEV master BRIDGE\|BOND\n"
		" ip link set DEV nomaster\n"
		" ip link add NAME type bridge\|bond\n"
		" ip link del DEV\n"
		" ip addr show [DEV]\n"
		" ip addr add CIDR dev DEV\n"
		" ip addr del CIDR dev DEV\n"
		@@ -289,6 +300,168 @@ namespace fresh { namespace cmd {
		return 0;
		}

		// ---- link add/del/master: bridges (ioctl) and bonds (sysfs) -------

		static bool isDir(const std::string &path){
		struct stat st;
		return stat(path.c_str(),&st)==0 && S_ISDIR(st.st_mode);
		}

		static bool isBridge(const std::string &dev){ return isDir("/sys/class/net/"+dev+"/bridge"); }
		static bool isBond(const std::string &dev){ return isDir("/sys/class/net/"+dev+"/bonding"); }

		// writes one line to a sysfs file; the kernel's answer is errno
		static bool writeSysfs(const std::string &path,const std::string &value){
		int fd=open(path.c_str(),O_WRONLY\|O_CLOEXEC);
		if(fd<0)
		return false;
		std::string v=value+"\n";
		bool ok=write(fd,v.data(),v.size())==(ssize_t)v.size();
		int e=errno;
		close(fd);
		errno=e;
		return ok;
		}

		// SIOCBR* take the name (ADDBR/DELBR) or an ifreq (ADDIF/DELIF)
		static int bridgeIoctl(unsigned long req,const std::string &bridge,const std::string &port){
		int s=ioctlSocket();
		if(s<0) return -1;
		int rc;
		if(port.empty()){
		char name[IFNAMSIZ]={0};
		strncpy(name,bridge.c_str(),IFNAMSIZ-1);
		rc=ioctl(s,req,name);
		}else{
		struct ifreq ifr;
		memset(&ifr,0,sizeof(ifr));
		strncpy(ifr.ifr_name,bridge.c_str(),IFNAMSIZ-1);
		ifr.ifr_ifindex=ifIndex(port);
		rc=ifr.ifr_ifindex ? ioctl(s,req,&ifr) : (errno=ENODEV,-1);
		}
		int e=errno;
		close(s);
		errno=e;
		return rc;
		}

		static bool validIfName(const std::string &name){
		if(name.empty() \|\| name.size()>=IFNAMSIZ \|\| name=="." \|\| name=="..")
		return false;
		for(char c:name)
		if(c=='/' \|\| c==':' \|\| c<=' ')
		return false;
		return true;
		}

		static int cmdLinkAdd(const std::string &name,const std::string &type){
		if(!validIfName(name)){
		std::cerr << "ip: link add: invalid name \"" << name << "\"" << std::endl;
		return 1;
		}
		if(ifIndex(name)){
		std::cerr << "ip: link add: " << name << ": " << strerror(EEXIST) << std::endl;
		return 1;
		}
		if(type=="bridge"){
		if(bridgeIoctl(SIOCBRADDBR,name,"")!=0){
		std::cerr << "ip: link add " << name << ": " << strerror(errno)
		<< (errno==ENOPKG \|\| errno==EINVAL \|\| errno==ENOTTY ? " (no bridge support in the kernel: CONFIG_BRIDGE)" : "")
		<< std::endl;
		return 1;
		}
		return 0;
		}
		if(type=="bond"){
		if(!writeSysfs("/sys/class/net/bonding_masters","+"+name)){
		std::cerr << "ip: link add " << name << ": "
		<< (errno==ENOENT ? "no bonding driver (CONFIG_BONDING)" : strerror(errno)) << std::endl;
		return 1;
		}
		return 0;
		}
		if(type.empty())
		std::cerr << "ip: link add: \"type bridge\" or \"type bond\" is required" << std::endl;
		else
		std::cerr << "ip: link add: type \"" << type << "\" isn't supported here (only bridge and bond)" << std::endl;
		return 1;
		}

		static int cmdLinkDel(const std::string &dev){
		if(!ifIndex(dev)){
		std::cerr << "ip: link del: " << dev << ": " << strerror(ENODEV) << std::endl;
		return 1;
		}
		if(isBridge(dev)){
		if(bridgeIoctl(SIOCBRDELBR,dev,"")!=0){
		// the kernel only deletes a bridge that is down
		std::cerr << "ip: link del " << dev << ": " << strerror(errno)
		<< (errno==EBUSY ? " (set it down first)" : "") << std::endl;
		return 1;
		}
		return 0;
		}
		if(isBond(dev)){
		if(!writeSysfs("/sys/class/net/bonding_masters","-"+dev)){
		std::cerr << "ip: link del " << dev << ": " << strerror(errno) << std::endl;
		return 1;
		}
		return 0;
		}
		std::cerr << "ip: link del: " << dev << " is neither a bridge nor a bond (others need netlink)" << std::endl;
		return 1;
		}

		// the bridge or bond dev is in now ("" if none)
		static std::string currentMaster(const std::string &dev){
		char buf[256];
		ssize_t n=readlink(("/sys/class/net/"+dev+"/master").c_str(),buf,sizeof(buf)-1);
		if(n<=0)
		return "";
		buf[n]=0;
		const char *slash=strrchr(buf,'/');
		return slash ? slash+1 : buf;
		}

		static int cmdLinkMaster(const std::string &dev,const std::string &master){
		if(!ifIndex(dev)){
		std::cerr << "ip: " << dev << ": " << strerror(ENODEV) << std::endl;
		return 1;
		}
		std::string old=currentMaster(dev);
		if(master.empty()){ // nomaster
		if(old.empty())
		return 0;
		bool ok=isBond(old) ? writeSysfs("/sys/class/net/"+old+"/bonding/slaves","-"+dev)
		: bridgeIoctl(SIOCBRDELIF,old,dev)==0;
		if(!ok){
		std::cerr << "ip: " << dev << ": nomaster: " << strerror(errno) << std::endl;
		return 1;
		}
		return 0;
		}
		if(old==master)
		return 0;
		if(!old.empty() && cmdLinkMaster(dev,"")!=0)
		return 1;
		bool ok;
		if(isBridge(master)){
		ok=bridgeIoctl(SIOCBRADDIF,master,dev)==0;
		}else if(isBond(master)){
		// the kernel wants a bond's slaves down when they join
		cmdLinkSet(dev,"down");
		ok=writeSysfs("/sys/class/net/"+master+"/bonding/slaves","+"+dev);
		}else{
		std::cerr << "ip: " << master << " is neither a bridge nor a bond" << std::endl;
		return 1;
		}
		if(!ok){
		std::cerr << "ip: " << dev << ": master " << master << ": " << strerror(errno) << std::endl;
		return 1;
		}
		return 0;
		}

		// ---- addr ---------------------------------------------------------

		static int cmdAddrShow(const std::string &onlyDev){
		@@ -564,14 +737,68 @@ namespace fresh { namespace cmd {
		const std::string &object=a[0];

		if(object=="link" \|\| object=="l"){
		std::string action=a.size()>=2 ? matchAction(a[1],{"show","set"}) : "show";
		if(action=="set" && a.size()>=3)
		return cmdLinkSet(a[2],a.size()>=4 ? a[3] : "");
		std::string action=a.size()>=2 ? matchAction(a[1],{"show","set","add","delete","del"}) : "show";
		if(action=="set"){
		if(a.size()<4){
		std::cerr << "ip: usage: ip link set DEV up\|down\|master BRIDGE\|nomaster" << std::endl;
		return 1;
		}
		// several settings at once: ip link set eth1 master br0 up
		int rc=0;
		for(size_t i=3;i<a.size() && rc==0;++i){
		if(a[i]=="up" \|\| a[i]=="down")
		rc=cmdLinkSet(a[2],a[i]);
		else if(a[i]=="master" && i+1<a.size())
		rc=cmdLinkMaster(a[2],a[++i]);
		else if(a[i]=="nomaster")
		rc=cmdLinkMaster(a[2],"");
		else{
		std::cerr << "ip: link set: unknown setting \"" << a[i] << "\"" << std::endl;
		rc=1;
		}
		}
		return rc;
		}
		if(action=="add"){
		// ip link add [name] NAME type TYPE
		std::string name,type;
		for(size_t i=2;i<a.size();++i){
		if(a[i]=="type" && i+1<a.size()) type=a[++i];
		else if(a[i]=="name" && i+1<a.size()) name=a[++i];
		else if(name.empty()) name=a[i];
		else{
		std::cerr << "ip: link add: unknown argument \"" << a[i] << "\"" << std::endl;
		return 1;
		}
		}
		return cmdLinkAdd(name,type);
		}
		if(action=="delete" \|\| action=="del"){
		std::string dev=a.size()>=3 ? a[2] : "";
		if(dev=="dev" && a.size()>=4) dev=a[3];
		if(dev.empty()){
		std::cerr << "ip: usage: ip link del DEV" << std::endl;
		return 1;
		}
		return cmdLinkDel(dev);
		}
		std::string dev;
		if(action=="show")
		dev=a.size()>=3 ? a[2] : "";
		else if(a.size()>=2) // bare "ip link eth0" convenience form
		else if(a.size()>=2){
		// bare "ip link eth0" convenience form -- only for an
		// interface that exists, anything else is a mistake
		if(!ifIndex(a[1])){
		std::cerr << "ip: link: unknown command or device \"" << a[1] << "\"" << std::endl;
		usage();
		return 1;
		}
		dev=a[1];
		}
		if(!dev.empty() && !ifIndex(dev)){
		std::cerr << "ip: " << dev << ": " << strerror(ENODEV) << std::endl;
		return 1;
		}
		return cmdLinkShow(dev,showStats);
		}

		@@ -596,8 +823,21 @@ namespace fresh { namespace cmd {
		std::string dev;
		if(action=="show")
		dev=a.size()>=3 ? a[2] : "";
		else if(a.size()>=2) // bare "ip addr eth0" convenience form
		else if(a.size()>=2){
		// bare "ip addr eth0" convenience form -- only for an
		// interface that exists
		if(!ifIndex(a[1])){
		std::cerr << "ip: addr: unknown command or device \"" << a[1] << "\"" << std::endl;
		usage();
		return 1;
		}
		dev=a[1];
		}
		if(dev=="dev" && action=="show" && a.size()>=4) dev=a[3]; // ip addr show dev eth0
		if(!dev.empty() && !ifIndex(dev)){
		std::cerr << "ip: " << dev << ": " << strerror(ENODEV) << std::endl;
		return 1;
		}
		return cmdAddrShow(dev);
		}

		@@ -613,6 +853,11 @@ namespace fresh { namespace cmd {
		}
		return cmdRouteAddDel(add,cidr,gateway,dev);
		}
		if(a.size()>=2 && action.empty()){
		std::cerr << "ip: route: unknown command \"" << a[1] << "\"" << std::endl;
		usage();
		return 1;
		}
		return cmdRouteShow();
		}