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Support adding, deleting, and clearing IPv6 addrs.

- Provide a function to add and delete IPv4/IPv6 addresses
  using netlink.
- Provide a function that clears all IP addresses on an
  interface that can be used by netd.

Also, a couple of cleanups:

- Update the header file to match reality, and include the
  header file in the implementation. Also fix a caller that
  has an incorrect method signature.
- Fix whitespace in Android.mk.

Change-Id: Ifba9d60cdfffb0b7e5c3b9c6ab328f5f77d259c4
  • Loading branch information...
commit 47ddb515b7d59b29d83628c1b4e48642dc0e49ba 1 parent b14bbf0
@lcolitti lcolitti authored
View
15 include/netutils/ifc.h
@@ -38,9 +38,13 @@ extern int ifc_reset_connections(const char *ifname, const int reset_mask);
extern int ifc_get_addr(const char *name, in_addr_t *addr);
extern int ifc_set_addr(const char *name, in_addr_t addr);
-extern int ifc_get_prefixLength(const char *name, uint32_t *prefixLength);
-extern int ifc_set_prefixLength(const char *name, uint32_t prefixLength);
+extern int ifc_add_address(const char *name, const char *address,
+ int prefixlen);
+extern int ifc_del_address(const char *name, const char *address,
+ int prefixlen);
+extern int ifc_set_prefixLength(const char *name, int prefixLength);
extern int ifc_set_hwaddr(const char *name, const void *ptr);
+extern int ifc_clear_addresses(const char *name);
/* This function is deprecated. Use ifc_add_route instead. */
extern int ifc_add_host_route(const char *name, in_addr_t addr);
@@ -53,9 +57,10 @@ extern int ifc_create_default_route(const char *name, in_addr_t addr);
extern int ifc_remove_default_route(const char *ifname);
extern int ifc_add_route(const char *name, const char *addr, int prefix_length,
const char *gw);
-
-extern int ifc_get_info(const char *name, in_addr_t *addr, in_addr_t *mask,
- in_addr_t *flags);
+extern int ifc_remove_route(const char *ifname, const char *dst,
+ int prefix_length, const char *gw);
+extern int ifc_get_info(const char *name, in_addr_t *addr, int *prefixLength,
+ unsigned *flags);
extern int ifc_configure(const char *ifname, in_addr_t address,
uint32_t prefixLength, in_addr_t gateway,
View
4 libnetutils/Android.mk
@@ -6,10 +6,10 @@ LOCAL_SRC_FILES:= \
dhcpmsg.c \
dhcp_utils.c \
ifc_utils.c \
- packet.c
+ packet.c
LOCAL_SHARED_LIBRARIES := \
- libcutils
+ libcutils
LOCAL_MODULE:= libnetutils
View
212 libnetutils/ifc_utils.c
@@ -26,15 +26,18 @@
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
+#include <netdb.h>
#include <linux/if.h>
#include <linux/if_ether.h>
#include <linux/if_arp.h>
-#include <linux/sockios.h>
+#include <linux/netlink.h>
#include <linux/route.h>
#include <linux/ipv6_route.h>
-#include <netdb.h>
-#include <linux/wireless.h>
+#include <linux/rtnetlink.h>
+#include <linux/sockios.h>
+
+#include "netutils/ifc.h"
#ifdef ANDROID
#define LOG_TAG "NetUtils"
@@ -52,6 +55,8 @@ static int ifc_ctl_sock6 = -1;
void printerr(char *fmt, ...);
#define DBG 0
+#define INET_ADDRLEN 4
+#define INET6_ADDRLEN 16
in_addr_t prefixLengthToIpv4Netmask(int prefix_length)
{
@@ -88,6 +93,28 @@ static const char *ipaddr_to_string(in_addr_t addr)
return inet_ntoa(in_addr);
}
+int string_to_ip(const char *string, struct sockaddr_storage *ss) {
+ struct addrinfo hints, *ai;
+ int ret;
+
+ if (ss == NULL) {
+ return -EFAULT;
+ }
+
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = AF_UNSPEC;
+ hints.ai_flags = AI_NUMERICHOST;
+ hints.ai_socktype = SOCK_DGRAM;
+
+ ret = getaddrinfo(string, NULL, &hints, &ai);
+ if (ret == 0) {
+ memcpy(ss, ai->ai_addr, ai->ai_addrlen);
+ freeaddrinfo(ai);
+ }
+
+ return ret;
+}
+
int ifc_init(void)
{
int ret;
@@ -209,6 +236,185 @@ int ifc_set_addr(const char *name, in_addr_t addr)
return ret;
}
+/*
+ * Adds or deletes an IP address on an interface.
+ *
+ * Action is one of:
+ * - RTM_NEWADDR (to add a new address)
+ * - RTM_DELADDR (to delete an existing address)
+ *
+ * Returns zero on success and negative errno on failure.
+ */
+int ifc_act_on_address(int action, const char *name, const char *address,
+ int prefixlen) {
+ int ifindex, s, len, ret;
+ struct sockaddr_storage ss;
+ void *addr;
+ size_t addrlen;
+ struct {
+ struct nlmsghdr n;
+ struct ifaddrmsg r;
+ // Allow for IPv6 address, headers, and padding.
+ char attrbuf[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+ NLMSG_ALIGN(sizeof(struct rtattr)) +
+ NLMSG_ALIGN(INET6_ADDRLEN)];
+ } req;
+ struct rtattr *rta;
+ struct nlmsghdr *nh;
+ struct nlmsgerr *err;
+ char buf[NLMSG_ALIGN(sizeof(struct nlmsghdr)) +
+ NLMSG_ALIGN(sizeof(struct nlmsgerr)) +
+ NLMSG_ALIGN(sizeof(struct nlmsghdr))];
+
+ // Get interface ID.
+ ifindex = if_nametoindex(name);
+ if (ifindex == 0) {
+ return -errno;
+ }
+
+ // Convert string representation to sockaddr_storage.
+ ret = string_to_ip(address, &ss);
+ if (ret) {
+ return ret;
+ }
+
+ // Determine address type and length.
+ if (ss.ss_family == AF_INET) {
+ struct sockaddr_in *sin = (struct sockaddr_in *) &ss;
+ addr = &sin->sin_addr;
+ addrlen = INET_ADDRLEN;
+ } else if (ss.ss_family == AF_INET6) {
+ struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) &ss;
+ addr = &sin6->sin6_addr;
+ addrlen = INET6_ADDRLEN;
+ } else {
+ return -EAFNOSUPPORT;
+ }
+
+ // Fill in netlink structures.
+ memset(&req, 0, sizeof(req));
+
+ // Netlink message header.
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.r));
+ req.n.nlmsg_type = action;
+ req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
+ req.n.nlmsg_pid = getpid();
+
+ // Interface address message header.
+ req.r.ifa_family = ss.ss_family;
+ req.r.ifa_prefixlen = prefixlen;
+ req.r.ifa_index = ifindex;
+
+ // Routing attribute. Contains the actual IP address.
+ rta = (struct rtattr *) (((char *) &req) + NLMSG_ALIGN(req.n.nlmsg_len));
+ rta->rta_type = IFA_LOCAL;
+ rta->rta_len = RTA_LENGTH(addrlen);
+ req.n.nlmsg_len = NLMSG_ALIGN(req.n.nlmsg_len) + RTA_LENGTH(addrlen);
+ memcpy(RTA_DATA(rta), addr, addrlen);
+
+ s = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+ if (send(s, &req, req.n.nlmsg_len, 0) < 0) {
+ close(s);
+ return -errno;
+ }
+
+ len = recv(s, buf, sizeof(buf), 0);
+ close(s);
+ if (len < 0) {
+ return -errno;
+ }
+
+ // Parse the acknowledgement to find the return code.
+ nh = (struct nlmsghdr *) buf;
+ if (!NLMSG_OK(nh, (unsigned) len) || nh->nlmsg_type != NLMSG_ERROR) {
+ return -EINVAL;
+ }
+ err = NLMSG_DATA(nh);
+
+ // Return code is negative errno.
+ return err->error;
+}
+
+int ifc_add_address(const char *name, const char *address, int prefixlen) {
+ return ifc_act_on_address(RTM_NEWADDR, name, address, prefixlen);
+}
+
+int ifc_del_address(const char *name, const char * address, int prefixlen) {
+ return ifc_act_on_address(RTM_DELADDR, name, address, prefixlen);
+}
+
+/*
+ * Clears IPv6 addresses on the specified interface.
+ */
+int ifc_clear_ipv6_addresses(const char *name) {
+ char rawaddrstr[INET6_ADDRSTRLEN], addrstr[INET6_ADDRSTRLEN];
+ unsigned int prefixlen;
+ int lasterror = 0, i, j, ret;
+ char ifname[64]; // Currently, IFNAMSIZ = 16.
+ FILE *f = fopen("/proc/net/if_inet6", "r");
+ if (!f) {
+ return -errno;
+ }
+
+ // Format:
+ // 20010db8000a0001fc446aa4b5b347ed 03 40 00 01 wlan0
+ while (fscanf(f, "%32s %*02x %02x %*02x %*02x %63s\n",
+ rawaddrstr, &prefixlen, ifname) == 3) {
+ // Is this the interface we're looking for?
+ if (strcmp(name, ifname)) {
+ continue;
+ }
+
+ // Put the colons back into the address.
+ for (i = 0, j = 0; i < 32; i++, j++) {
+ addrstr[j] = rawaddrstr[i];
+ if (i % 4 == 3) {
+ addrstr[++j] = ':';
+ }
+ }
+ addrstr[j - 1] = '\0';
+
+ // Don't delete the link-local address as well, or it will disable IPv6
+ // on the interface.
+ if (strncmp(addrstr, "fe80:", 5) == 0) {
+ continue;
+ }
+
+ ret = ifc_del_address(ifname, addrstr, prefixlen);
+ if (ret) {
+ LOGE("Deleting address %s/%d on %s: %s", addrstr, prefixlen, ifname,
+ strerror(-ret));
+ lasterror = ret;
+ }
+ }
+
+ fclose(f);
+ return lasterror;
+}
+
+/*
+ * Clears IPv4 addresses on the specified interface.
+ */
+void ifc_clear_ipv4_addresses(const char *name) {
+ unsigned count, addr;
+ ifc_init();
+ for (count=0, addr=1;((addr != 0) && (count < 255)); count++) {
+ if (ifc_get_addr(name, &addr) < 0)
+ break;
+ if (addr)
+ ifc_set_addr(name, 0);
+ }
+ ifc_close();
+}
+
+/*
+ * Clears all IP addresses on the specified interface.
+ */
+int ifc_clear_addresses(const char *name) {
+ ifc_clear_ipv4_addresses(name);
+ return ifc_clear_ipv6_addresses(name);
+}
+
int ifc_set_hwaddr(const char *name, const void *ptr)
{
int r;
View
3  netcfg/netcfg.c
@@ -50,8 +50,9 @@ void usage(void)
int dump_interface(const char *name)
{
- unsigned addr, prefixLength, flags;
+ unsigned addr, flags;
unsigned char hwbuf[ETH_ALEN];
+ int prefixLength;
if(ifc_get_info(name, &addr, &prefixLength, &flags)) {
return 0;
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