diff --git a/Clients/Makefile b/Clients/Makefile
index 383af31..925c20e 100755
--- a/Clients/Makefile
+++ b/Clients/Makefile
@@ -36,7 +36,7 @@ TARGETS = build/dns-sd build/dns-sd64
LIBS =
else
TARGETS = build/dns-sd
-LIBS = -L../mDNSPosix/build/prod/ -ldns_sd
+LIBS ?= -L../mDNSPosix/build/prod/ -ldns_sd
endif
all: $(TARGETS)
diff --git a/mDNSPosix/PosixDaemon.c b/mDNSPosix/PosixDaemon.c
index 88b3292..e86a6c7 100644
--- a/mDNSPosix/PosixDaemon.c
+++ b/mDNSPosix/PosixDaemon.c
@@ -37,6 +37,11 @@
#include <fcntl.h>
#include <pwd.h>
#include <sys/types.h>
+#ifdef __linux__
+#include <sys/capability.h> /* !!! We require libcap-dev for this. Oh well. */
+/* prctl is required to enable inheriting of capabilities across setuid */
+#include <sys/prctl.h>
+#endif /* __linux__ */
#if __APPLE__
#undef daemon
@@ -184,16 +189,50 @@ int main(int argc, char **argv)
Reconfigure(&mDNSStorage);
+#ifdef __linux__
+ /*
+ * SO_BINDTODEVICE is privileged operation; however, we can get
+ * around it using capabilities instead of remaining root.
+ */
+ if (mStatus_NoError == err)
+ {
+ if (prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0) < 0)
+ perror("prctl PR_SET_KEEPCAPS");
+ }
+#endif /* __linux__ */
+
// Now that we're finished with anything privileged, switch over to running as "nobody"
if (mStatus_NoError == err)
{
const struct passwd *pw = getpwnam("nobody");
if (pw != NULL)
+ {
setuid(pw->pw_uid);
+#ifdef __linux__
+ struct __user_cap_header_struct ch;
+ struct __user_cap_data_struct cd[_LINUX_CAPABILITY_U32S_3];
+
+ memset(&ch, 0, sizeof(ch));
+ ch.version = _LINUX_CAPABILITY_VERSION_3;
+ ch.pid = getpid();
+ memset(&cd[0], 0, sizeof(cd));
+ /* CAP_NET_RAW is required to use SO_BINDTODEVICE */
+ int caps = CAP_TO_MASK(CAP_NET_RAW);
+ cd[0].permitted = caps;
+ cd[0].effective = caps;
+ if (capset(&ch, &cd[0]) < 0)
+ perror("capset");
+#endif /* __linux__ */
+ }
else
LogMsg("WARNING: mdnsd continuing as root because user \"nobody\" does not exist");
}
+#ifdef __linux__
+ if (mStatus_NoError == err)
+ err = mDNSPlatformPosixRefreshInterfaceList(&mDNSStorage);
+#endif /* __linux__ */
+
if (mStatus_NoError == err)
err = MainLoop(&mDNSStorage);
diff --git a/mDNSPosix/mDNSPosix.c b/mDNSPosix/mDNSPosix.c
index 6effa12..7c1d6eb 100755
--- a/mDNSPosix/mDNSPosix.c
+++ b/mDNSPosix/mDNSPosix.c
@@ -733,6 +741,29 @@ mDNSlocal int SetupSocket(struct sockaddr *intfAddr, mDNSIPPort port, int interf
if (err < 0) { err = errno; perror("setsockopt - IP_MULTICAST_TTL"); }
}
+#ifdef __linux__
+#ifdef SO_BINDTODEVICE
+ if (err == 0 && interfaceIndex)
+ {
+ char ifname[IFNAMSIZ];
+ if (if_indextoname(interfaceIndex, ifname))
+ {
+ err = setsockopt(*sktPtr, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
+ if (err < 0)
+ {
+ err = errno;
+ perror("setsockopt - SO_BINDTODEVICE");
+ }
+ }
+ else
+ {
+ err = errno;
+ perror("if_indextoname");
+ }
+ }
+#endif /* SO_BINDTODEVICE */
+#endif /* __linux__ */
+
// And start listening for packets
if (err == 0)
{
@@ -814,6 +845,29 @@ mDNSlocal int SetupSocket(struct sockaddr *intfAddr, mDNSIPPort port, int interf
if (err < 0) { err = errno; perror("setsockopt - IPV6_MULTICAST_HOPS"); }
}
+#ifdef __linux__
+#ifdef SO_BINDTODEVICE
+ if (err == 0 && interfaceIndex)
+ {
+ char ifname[IFNAMSIZ];
+ if (if_indextoname(interfaceIndex, ifname))
+ {
+ err = setsockopt(*sktPtr, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
+ if (err < 0)
+ {
+ err = errno;
+ perror("setsockopt - SO_BINDTODEVICE");
+ }
+ }
+ else
+ {
+ err = errno;
+ perror("if_indextoname");
+ }
+ }
+#endif /* SO_BINDTODEVICE */
+#endif /* __linux__ */
+
// And start listening for packets
if (err == 0)
{
@@ -958,19 +1017,14 @@ mDNSlocal int SetupInterfaceList(mDNS *const m)
int err = 0;
struct ifi_info *intfList = get_ifi_info(AF_INET, mDNStrue);
struct ifi_info *firstLoopback = NULL;
+ struct ifi_info **p = &intfList;
assert(m != NULL);
debugf("SetupInterfaceList");
- if (intfList == NULL) err = ENOENT;
-
#if HAVE_IPV6
- if (err == 0) /* Link the IPv6 list to the end of the IPv4 list */
- {
- struct ifi_info **p = &intfList;
- while (*p) p = &(*p)->ifi_next;
- *p = get_ifi_info(AF_INET6, mDNStrue);
- }
+ while (*p) p = &(*p)->ifi_next;
+ *p = get_ifi_info(AF_INET6, mDNStrue);
#endif
if (err == 0)
@@ -1046,7 +1100,7 @@ mDNSlocal mStatus OpenIfNotifySocket(int *pFD)
/* Subscribe the socket to Link & IP addr notifications. */
mDNSPlatformMemZero(&snl, sizeof snl);
snl.nl_family = AF_NETLINK;
- snl.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR;
+ snl.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR | RTMGRP_IPV6_IFADDR;
ret = bind(sock, (struct sockaddr *) &snl, sizeof snl);
if (0 == ret)
*pFD = sock;
@@ -1124,11 +1178,18 @@ mDNSlocal mDNSu32 ProcessRoutingNotification(int sd)
PrintNetLinkMsg(pNLMsg);
#endif
+ // this result isn't used anywhere as a number, just as
+ // non-zero - however, I have seen devices with more than 32
+ // interfaces at some point..
+ // (on Linux, every tunnel increases index for example)
+
// Process the NetLink message
if (pNLMsg->nlmsg_type == RTM_GETLINK || pNLMsg->nlmsg_type == RTM_NEWLINK)
- result |= 1 << ((struct ifinfomsg*) NLMSG_DATA(pNLMsg))->ifi_index;
+ result |= 1;
+ // << ((struct ifinfomsg*) NLMSG_DATA(pNLMsg))->ifi_index;
else if (pNLMsg->nlmsg_type == RTM_DELADDR || pNLMsg->nlmsg_type == RTM_NEWADDR)
- result |= 1 << ((struct ifaddrmsg*) NLMSG_DATA(pNLMsg))->ifa_index;
+ result |= 1;
+ // << ((struct ifaddrmsg*) NLMSG_DATA(pNLMsg))->ifa_index;
// Advance pNLMsg to the next message in the buffer
if ((pNLMsg->nlmsg_flags & NLM_F_MULTI) != 0 && pNLMsg->nlmsg_type != NLMSG_DONE)
@@ -1299,8 +1360,12 @@ mDNSexport mStatus mDNSPlatformInit(mDNS *const m)
if (err == mStatus_NoError) err = SetupSocket(&sa, zeroIPPort, 0, &m->p->unicastSocket6);
#endif
+ // In Linux case, we can't set up sockets with different owner -
+ // it blows up SO_REUSEPORT. So we do this step bit later.
+#ifndef __linux__
// Tell mDNS core about the network interfaces on this machine.
if (err == mStatus_NoError) err = SetupInterfaceList(m);
+#endif /* !__linux__ */
// Tell mDNS core about DNS Servers
mDNS_Lock(m);
diff --git a/mDNSPosix/mDNSUNP.c b/mDNSPosix/mDNSUNP.c
index b392fc7..f551ad5 100755
--- a/mDNSPosix/mDNSUNP.c
+++ b/mDNSPosix/mDNSUNP.c
@@ -63,6 +63,7 @@
#if defined(AF_INET6) && HAVE_IPV6 && HAVE_LINUX
#include <netdb.h>
#include <arpa/inet.h>
+#include <linux/if_addr.h>
/* Converts a prefix length to IPv6 network mask */
void plen_to_mask(int plen, char *addr) {
@@ -127,6 +128,8 @@
nitems = fscanf(fp, ifnameFmt, ifname);
if (nitems != 1) break;
+ if (flags & IFA_F_DEPRECATED) continue;
+
if (strcmp(lastname, ifname) == 0) {
if (doaliases == 0)
continue; /* already processed this interface */
diff --git a/mDNSShared/dnsextd_parser.y b/mDNSShared/dnsextd_parser.y
index 18c5990..d4b63ce 100644
--- a/mDNSShared/dnsextd_parser.y
+++ b/mDNSShared/dnsextd_parser.y
@@ -15,6 +15,8 @@
* limitations under the License.
*/
+%parse-param { void *context }
+
%{
#include <stdio.h>
#include <stdlib.h>
@@ -23,7 +25,7 @@
#include "DebugServices.h"
#include "dnsextd.h"
-void yyerror( const char* error );
+void yyerror( void *context, const char* error );
int yylex(void);
@@ -409,7 +419,7 @@ int yywrap(void);
extern int yylineno;
-void yyerror( const char *str )
+void yyerror( void *context, const char *str )
{
fprintf( stderr,"%s:%d: error: %s\n", g_filename, yylineno, str );
}