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-rw-r--r--src/l2_packet/l2_packet_privsep.c267
1 files changed, 267 insertions, 0 deletions
diff --git a/src/l2_packet/l2_packet_privsep.c b/src/l2_packet/l2_packet_privsep.c
new file mode 100644
index 0000000..c0e7c49
--- /dev/null
+++ b/src/l2_packet/l2_packet_privsep.c
@@ -0,0 +1,267 @@
+/*
+ * WPA Supplicant - Layer2 packet handling with privilege separation
+ * Copyright (c) 2007, Jouni Malinen <j@w1.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "includes.h"
+#include <sys/un.h>
+
+#include "common.h"
+#include "eloop.h"
+#include "l2_packet.h"
+#include "privsep_commands.h"
+
+
+struct l2_packet_data {
+ int fd; /* UNIX domain socket for privsep access */
+ void (*rx_callback)(void *ctx, const u8 *src_addr,
+ const u8 *buf, size_t len);
+ void *rx_callback_ctx;
+ u8 own_addr[ETH_ALEN];
+ char *own_socket_path;
+ struct sockaddr_un priv_addr;
+};
+
+
+static int wpa_priv_cmd(struct l2_packet_data *l2, int cmd,
+ const void *data, size_t data_len)
+{
+ struct msghdr msg;
+ struct iovec io[2];
+
+ io[0].iov_base = &cmd;
+ io[0].iov_len = sizeof(cmd);
+ io[1].iov_base = (u8 *) data;
+ io[1].iov_len = data_len;
+
+ os_memset(&msg, 0, sizeof(msg));
+ msg.msg_iov = io;
+ msg.msg_iovlen = data ? 2 : 1;
+ msg.msg_name = &l2->priv_addr;
+ msg.msg_namelen = sizeof(l2->priv_addr);
+
+ if (sendmsg(l2->fd, &msg, 0) < 0) {
+ perror("L2: sendmsg(cmd)");
+ return -1;
+ }
+
+ return 0;
+}
+
+
+int l2_packet_get_own_addr(struct l2_packet_data *l2, u8 *addr)
+{
+ os_memcpy(addr, l2->own_addr, ETH_ALEN);
+ return 0;
+}
+
+
+int l2_packet_send(struct l2_packet_data *l2, const u8 *dst_addr, u16 proto,
+ const u8 *buf, size_t len)
+{
+ struct msghdr msg;
+ struct iovec io[4];
+ int cmd = PRIVSEP_CMD_L2_SEND;
+
+ io[0].iov_base = &cmd;
+ io[0].iov_len = sizeof(cmd);
+ io[1].iov_base = &dst_addr;
+ io[1].iov_len = ETH_ALEN;
+ io[2].iov_base = &proto;
+ io[2].iov_len = 2;
+ io[3].iov_base = (u8 *) buf;
+ io[3].iov_len = len;
+
+ os_memset(&msg, 0, sizeof(msg));
+ msg.msg_iov = io;
+ msg.msg_iovlen = 4;
+ msg.msg_name = &l2->priv_addr;
+ msg.msg_namelen = sizeof(l2->priv_addr);
+
+ if (sendmsg(l2->fd, &msg, 0) < 0) {
+ perror("L2: sendmsg(packet_send)");
+ return -1;
+ }
+
+ return 0;
+}
+
+
+static void l2_packet_receive(int sock, void *eloop_ctx, void *sock_ctx)
+{
+ struct l2_packet_data *l2 = eloop_ctx;
+ u8 buf[2300];
+ int res;
+ struct sockaddr_un from;
+ socklen_t fromlen = sizeof(from);
+
+ os_memset(&from, 0, sizeof(from));
+ res = recvfrom(sock, buf, sizeof(buf), 0, (struct sockaddr *) &from,
+ &fromlen);
+ if (res < 0) {
+ perror("l2_packet_receive - recvfrom");
+ return;
+ }
+ if (res < ETH_ALEN) {
+ wpa_printf(MSG_DEBUG, "L2: Too show packet received");
+ return;
+ }
+
+ if (from.sun_family != AF_UNIX ||
+ os_strncmp(from.sun_path, l2->priv_addr.sun_path,
+ sizeof(from.sun_path)) != 0) {
+ wpa_printf(MSG_DEBUG, "L2: Received message from unexpected "
+ "source");
+ return;
+ }
+
+ l2->rx_callback(l2->rx_callback_ctx, buf, buf + ETH_ALEN,
+ res - ETH_ALEN);
+}
+
+
+struct l2_packet_data * l2_packet_init(
+ const char *ifname, const u8 *own_addr, unsigned short protocol,
+ void (*rx_callback)(void *ctx, const u8 *src_addr,
+ const u8 *buf, size_t len),
+ void *rx_callback_ctx, int l2_hdr)
+{
+ struct l2_packet_data *l2;
+ char *own_dir = "/tmp";
+ char *priv_dir = "/var/run/wpa_priv";
+ size_t len;
+ static unsigned int counter = 0;
+ struct sockaddr_un addr;
+ fd_set rfds;
+ struct timeval tv;
+ int res;
+ u8 reply[ETH_ALEN + 1];
+ int reg_cmd[2];
+
+ l2 = os_zalloc(sizeof(struct l2_packet_data));
+ if (l2 == NULL)
+ return NULL;
+ l2->rx_callback = rx_callback;
+ l2->rx_callback_ctx = rx_callback_ctx;
+
+ len = os_strlen(own_dir) + 50;
+ l2->own_socket_path = os_malloc(len);
+ if (l2->own_socket_path == NULL) {
+ os_free(l2);
+ return NULL;
+ }
+ os_snprintf(l2->own_socket_path, len, "%s/wpa_privsep-l2-%d-%d",
+ own_dir, getpid(), counter++);
+
+ l2->priv_addr.sun_family = AF_UNIX;
+ os_snprintf(l2->priv_addr.sun_path, sizeof(l2->priv_addr.sun_path),
+ "%s/%s", priv_dir, ifname);
+
+ l2->fd = socket(PF_UNIX, SOCK_DGRAM, 0);
+ if (l2->fd < 0) {
+ perror("socket(PF_UNIX)");
+ os_free(l2->own_socket_path);
+ l2->own_socket_path = NULL;
+ os_free(l2);
+ return NULL;
+ }
+
+ os_memset(&addr, 0, sizeof(addr));
+ addr.sun_family = AF_UNIX;
+ os_strlcpy(addr.sun_path, l2->own_socket_path, sizeof(addr.sun_path));
+ if (bind(l2->fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
+ perror("bind(PF_UNIX)");
+ goto fail;
+ }
+
+ reg_cmd[0] = protocol;
+ reg_cmd[1] = l2_hdr;
+ if (wpa_priv_cmd(l2, PRIVSEP_CMD_L2_REGISTER, reg_cmd, sizeof(reg_cmd))
+ < 0) {
+ wpa_printf(MSG_ERROR, "L2: Failed to register with wpa_priv");
+ goto fail;
+ }
+
+ FD_ZERO(&rfds);
+ FD_SET(l2->fd, &rfds);
+ tv.tv_sec = 5;
+ tv.tv_usec = 0;
+ res = select(l2->fd + 1, &rfds, NULL, NULL, &tv);
+ if (res < 0 && errno != EINTR) {
+ perror("select");
+ goto fail;
+ }
+
+ if (FD_ISSET(l2->fd, &rfds)) {
+ res = recv(l2->fd, reply, sizeof(reply), 0);
+ if (res < 0) {
+ perror("recv");
+ goto fail;
+ }
+ } else {
+ wpa_printf(MSG_DEBUG, "L2: Timeout while waiting for "
+ "registration reply");
+ goto fail;
+ }
+
+ if (res != ETH_ALEN) {
+ wpa_printf(MSG_DEBUG, "L2: Unexpected registration reply "
+ "(len=%d)", res);
+ }
+ os_memcpy(l2->own_addr, reply, ETH_ALEN);
+
+ eloop_register_read_sock(l2->fd, l2_packet_receive, l2, NULL);
+
+ return l2;
+
+fail:
+ close(l2->fd);
+ l2->fd = -1;
+ unlink(l2->own_socket_path);
+ os_free(l2->own_socket_path);
+ l2->own_socket_path = NULL;
+ os_free(l2);
+ return NULL;
+}
+
+
+void l2_packet_deinit(struct l2_packet_data *l2)
+{
+ if (l2 == NULL)
+ return;
+
+ if (l2->fd >= 0) {
+ wpa_priv_cmd(l2, PRIVSEP_CMD_L2_UNREGISTER, NULL, 0);
+ eloop_unregister_read_sock(l2->fd);
+ close(l2->fd);
+ }
+
+ if (l2->own_socket_path) {
+ unlink(l2->own_socket_path);
+ os_free(l2->own_socket_path);
+ }
+
+ os_free(l2);
+}
+
+
+int l2_packet_get_ip_addr(struct l2_packet_data *l2, char *buf, size_t len)
+{
+ /* TODO */
+ return -1;
+}
+
+
+void l2_packet_notify_auth_start(struct l2_packet_data *l2)
+{
+ wpa_priv_cmd(l2, PRIVSEP_CMD_L2_NOTIFY_AUTH_START, NULL, 0);
+}