network: add netns_getifaddrs() implementation

src/include/ifaddrs.h → src/include/netns_ifaddrs.h

-#ifndef _IFADDRS_H
-#define _IFADDRS_H
+#ifndef _LXC_NETNS_IFADDRS_H
+#define _LXC_NETNS_IFADDRS_H
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 #include <features.h>
+#include <linux/types.h>
 #include <netinet/in.h>
+#include <stdbool.h>
 #include <sys/socket.h>
 
-struct ifaddrs {
-	struct ifaddrs *ifa_next;
+struct netns_ifaddrs {
+	struct netns_ifaddrs *ifa_next;
+
+	/* Can - but shouldn't be - NULL. */
 	char *ifa_name;
+
+	/* This field is not present struct ifaddrs. */
+	int ifa_ifindex;
+
 	unsigned ifa_flags;
+
+	/* This field is not present struct ifaddrs. */
+	int ifa_mtu;
+
+	/* This field is not present struct ifaddrs. */
+	int ifa_prefixlen;
+
 	struct sockaddr *ifa_addr;
 	struct sockaddr *ifa_netmask;
 	union {
 		struct sockaddr *ifu_broadaddr;
 		struct sockaddr *ifu_dstaddr;
 	} ifa_ifu;
+
+	/* If you don't know what this is for don't touch it. */
 	void *ifa_data;
 };
-#define ifa_broadaddr ifa_ifu.ifu_broadaddr
-#define ifa_dstaddr ifa_ifu.ifu_dstaddr
 
-void freeifaddrs(struct ifaddrs *);
-int getifaddrs(struct ifaddrs **);
+#define __ifa_broadaddr ifa_ifu.ifu_broadaddr
+#define __ifa_dstaddr ifa_ifu.ifu_dstaddr
+
+extern void netns_freeifaddrs(struct netns_ifaddrs *);
+extern int netns_getifaddrs(struct netns_ifaddrs **ifap, __s32 netns_id,
+			    bool *netnsid_aware);
 
 #ifdef __cplusplus
 }
 #endif
 
-#endif
+#endif /* _LXC_NETNS_IFADDRS_H */

src/lxc/Makefile.am

@@ -13,6 +13,7 @@ noinst_HEADERS = attach.h \
 		 criu.h \
 		 error.h \
 		 file_utils.h \
+		 ../include/netns_ifaddrs.h \
 		 initutils.h \
 		 list.h \
 		 log.h \
@@ -40,10 +41,6 @@ noinst_HEADERS = attach.h \
 		 tools/arguments.h \
 		 utils.h
 
-if !HAVE_IFADDRS_H
-noinst_HEADERS += ../include/ifaddrs.h
-endif
-
 if IS_BIONIC
 noinst_HEADERS += ../include/lxcmntent.h \
 		  ../include/openpty.h
@@ -101,6 +98,7 @@ liblxc_la_SOURCES = af_unix.c af_unix.h \
 		    execute.c \
 		    freezer.c \
 		    file_utils.c file_utils.h \
+		    ../include/netns_ifaddrs.c ../include/netns_ifaddrs.h \
 		    initutils.c initutils.h \
 		    list.h \
 		    log.c log.h \
@@ -137,10 +135,6 @@ liblxc_la_SOURCES = af_unix.c af_unix.h \
 		    version.h \
 		    $(LSM_SOURCES)
 
-if !HAVE_IFADDRS_H
-liblxc_la_SOURCES += ../include/ifaddrs.c ../include/ifaddrs.h
-endif
-
 if IS_BIONIC
 liblxc_la_SOURCES += ../include/lxcmntent.c ../include/lxcmntent.h \
 		     ../include/openpty.c ../include/openpty.h

src/lxc/macro.h

@@ -272,10 +272,20 @@ extern int __build_bug_on_failed;
 #define IFLA_NEW_NETNSID 45
 #endif
 
-#ifndef IFLA_IF_NETNSID
+#ifdef IFLA_IF_NETNSID
+#ifndef IFLA_TARGET_NETNSID
+#define IFLA_TARGET_NETNSID = IFLA_IF_NETNSID
+#endif
+#else
 #define IFLA_IF_NETNSID 46
+#define IFLA_TARGET_NETNSID 46
+#endif
+
+#ifndef IFA_TARGET_NETNSID
+#define IFA_TARGET_NETNSID 10
 #endif
 
+
 #ifndef RTM_NEWNSID
 #define RTM_NEWNSID 88
 #endif
@@ -304,6 +314,16 @@ extern int __build_bug_on_failed;
 #define MACVLAN_MODE_PASSTHRU 8
 #endif
 
+/* Attributes of RTM_NEWNSID/RTM_GETNSID messages */
+enum {
+	__LXC_NETNSA_NONE,
+#define __LXC_NETNSA_NSID_NOT_ASSIGNED -1
+	__LXC_NETNSA_NSID,
+	__LXC_NETNSA_PID,
+	__LXC_NETNSA_FD,
+	__LXC_NETNSA_MAX,
+};
+
 /* Length of abstract unix domain socket socket address. */
 #define LXC_AUDS_ADDR_LEN sizeof(((struct sockaddr_un *)0)->sun_path)
 

src/lxc/network.c

@@ -3181,35 +3181,6 @@ void lxc_delete_network(struct lxc_handler *handler)
 		DEBUG("Deleted network devices");
 }
 
-int addattr(struct nlmsghdr *n, size_t maxlen, int type, const void *data, size_t alen)
-{
-	int len = RTA_LENGTH(alen);
-	struct rtattr *rta;
-
-	errno = EMSGSIZE;
-	if (NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len) > maxlen)
-		return -1;
-
-	rta = NLMSG_TAIL(n);
-	rta->rta_type = type;
-	rta->rta_len = len;
-	if (alen)
-		memcpy(RTA_DATA(rta), data, alen);
-	n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
-
-	return 0;
-}
-
-/* Attributes of RTM_NEWNSID/RTM_GETNSID messages */
-enum {
-	__LXC_NETNSA_NONE,
-#define __LXC_NETNSA_NSID_NOT_ASSIGNED -1
-	__LXC_NETNSA_NSID,
-	__LXC_NETNSA_PID,
-	__LXC_NETNSA_FD,
-	__LXC_NETNSA_MAX,
-};
-
 int lxc_netns_set_nsid(int fd)
 {
 	int ret;

src/lxc/nl.c

@@ -345,3 +345,22 @@ extern int netlink_close(struct nl_handler *handler)
 	return 0;
 }
 
+int addattr(struct nlmsghdr *n, size_t maxlen, int type, const void *data,
+	    size_t alen)
+{
+	int len = RTA_LENGTH(alen);
+	struct rtattr *rta;
+
+	errno = EMSGSIZE;
+	if (NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len) > maxlen)
+		return -1;
+
+	rta = NLMSG_TAIL(n);
+	rta->rta_type = type;
+	rta->rta_len = len;
+	if (alen)
+		memcpy(RTA_DATA(rta), data, alen);
+	n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
+
+	return 0;
+}

src/lxc/nl.h

@@ -23,6 +23,8 @@
 #ifndef __LXC_NL_H
 #define __LXC_NL_H
 
+#include <stdio.h>
+
 /*
  * Use this as a good size to allocate generic netlink messages
  */
@@ -259,5 +261,7 @@ void nlmsg_free(struct nlmsg *nlmsg);
  */
 void *nlmsg_data(struct nlmsg *nlmsg);
 
+extern int addattr(struct nlmsghdr *n, size_t maxlen, int type,
+		   const void *data, size_t alen);
 
 #endif