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-rw-r--r--qemu/qemu-bridge-helper.c442
1 files changed, 0 insertions, 442 deletions
diff --git a/qemu/qemu-bridge-helper.c b/qemu/qemu-bridge-helper.c
deleted file mode 100644
index 830fb9e26..000000000
--- a/qemu/qemu-bridge-helper.c
+++ /dev/null
@@ -1,442 +0,0 @@
-/*
- * QEMU Bridge Helper
- *
- * Copyright IBM, Corp. 2011
- *
- * Authors:
- * Anthony Liguori <aliguori@us.ibm.com>
- * Richa Marwaha <rmarwah@linux.vnet.ibm.com>
- * Corey Bryant <coreyb@linux.vnet.ibm.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- */
-
-#include "qemu/osdep.h"
-
-#include <glib.h>
-
-#include <sys/ioctl.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <sys/prctl.h>
-
-#include <net/if.h>
-
-#include <linux/sockios.h>
-
-#ifndef SIOCBRADDIF
-#include <linux/if_bridge.h>
-#endif
-
-#include "qemu/queue.h"
-
-#include "net/tap-linux.h"
-
-#ifdef CONFIG_LIBCAP
-#include <cap-ng.h>
-#endif
-
-#define DEFAULT_ACL_FILE CONFIG_QEMU_CONFDIR "/bridge.conf"
-
-enum {
- ACL_ALLOW = 0,
- ACL_ALLOW_ALL,
- ACL_DENY,
- ACL_DENY_ALL,
-};
-
-typedef struct ACLRule {
- int type;
- char iface[IFNAMSIZ];
- QSIMPLEQ_ENTRY(ACLRule) entry;
-} ACLRule;
-
-typedef QSIMPLEQ_HEAD(ACLList, ACLRule) ACLList;
-
-static void usage(void)
-{
- fprintf(stderr,
- "Usage: qemu-bridge-helper [--use-vnet] --br=bridge --fd=unixfd\n");
-}
-
-static int parse_acl_file(const char *filename, ACLList *acl_list)
-{
- FILE *f;
- char line[4096];
- ACLRule *acl_rule;
-
- f = fopen(filename, "r");
- if (f == NULL) {
- return -1;
- }
-
- while (fgets(line, sizeof(line), f) != NULL) {
- char *ptr = line;
- char *cmd, *arg, *argend;
-
- while (isspace(*ptr)) {
- ptr++;
- }
-
- /* skip comments and empty lines */
- if (*ptr == '#' || *ptr == 0) {
- continue;
- }
-
- cmd = ptr;
- arg = strchr(cmd, ' ');
- if (arg == NULL) {
- arg = strchr(cmd, '\t');
- }
-
- if (arg == NULL) {
- fprintf(stderr, "Invalid config line:\n %s\n", line);
- fclose(f);
- errno = EINVAL;
- return -1;
- }
-
- *arg = 0;
- arg++;
- while (isspace(*arg)) {
- arg++;
- }
-
- argend = arg + strlen(arg);
- while (arg != argend && isspace(*(argend - 1))) {
- argend--;
- }
- *argend = 0;
-
- if (strcmp(cmd, "deny") == 0) {
- acl_rule = g_malloc(sizeof(*acl_rule));
- if (strcmp(arg, "all") == 0) {
- acl_rule->type = ACL_DENY_ALL;
- } else {
- acl_rule->type = ACL_DENY;
- snprintf(acl_rule->iface, IFNAMSIZ, "%s", arg);
- }
- QSIMPLEQ_INSERT_TAIL(acl_list, acl_rule, entry);
- } else if (strcmp(cmd, "allow") == 0) {
- acl_rule = g_malloc(sizeof(*acl_rule));
- if (strcmp(arg, "all") == 0) {
- acl_rule->type = ACL_ALLOW_ALL;
- } else {
- acl_rule->type = ACL_ALLOW;
- snprintf(acl_rule->iface, IFNAMSIZ, "%s", arg);
- }
- QSIMPLEQ_INSERT_TAIL(acl_list, acl_rule, entry);
- } else if (strcmp(cmd, "include") == 0) {
- /* ignore errors */
- parse_acl_file(arg, acl_list);
- } else {
- fprintf(stderr, "Unknown command `%s'\n", cmd);
- fclose(f);
- errno = EINVAL;
- return -1;
- }
- }
-
- fclose(f);
-
- return 0;
-}
-
-static bool has_vnet_hdr(int fd)
-{
- unsigned int features = 0;
-
- if (ioctl(fd, TUNGETFEATURES, &features) == -1) {
- return false;
- }
-
- if (!(features & IFF_VNET_HDR)) {
- return false;
- }
-
- return true;
-}
-
-static void prep_ifreq(struct ifreq *ifr, const char *ifname)
-{
- memset(ifr, 0, sizeof(*ifr));
- snprintf(ifr->ifr_name, IFNAMSIZ, "%s", ifname);
-}
-
-static int send_fd(int c, int fd)
-{
- char msgbuf[CMSG_SPACE(sizeof(fd))];
- struct msghdr msg = {
- .msg_control = msgbuf,
- .msg_controllen = sizeof(msgbuf),
- };
- struct cmsghdr *cmsg;
- struct iovec iov;
- char req[1] = { 0x00 };
-
- cmsg = CMSG_FIRSTHDR(&msg);
- cmsg->cmsg_level = SOL_SOCKET;
- cmsg->cmsg_type = SCM_RIGHTS;
- cmsg->cmsg_len = CMSG_LEN(sizeof(fd));
- msg.msg_controllen = cmsg->cmsg_len;
-
- iov.iov_base = req;
- iov.iov_len = sizeof(req);
-
- msg.msg_iov = &iov;
- msg.msg_iovlen = 1;
- memcpy(CMSG_DATA(cmsg), &fd, sizeof(fd));
-
- return sendmsg(c, &msg, 0);
-}
-
-#ifdef CONFIG_LIBCAP
-static int drop_privileges(void)
-{
- /* clear all capabilities */
- capng_clear(CAPNG_SELECT_BOTH);
-
- if (capng_update(CAPNG_ADD, CAPNG_EFFECTIVE | CAPNG_PERMITTED,
- CAP_NET_ADMIN) < 0) {
- return -1;
- }
-
- /* change to calling user's real uid and gid, retaining supplemental
- * groups and CAP_NET_ADMIN */
- if (capng_change_id(getuid(), getgid(), CAPNG_CLEAR_BOUNDING)) {
- return -1;
- }
-
- return 0;
-}
-#endif
-
-int main(int argc, char **argv)
-{
- struct ifreq ifr;
-#ifndef SIOCBRADDIF
- unsigned long ifargs[4];
-#endif
- int ifindex;
- int fd = -1, ctlfd = -1, unixfd = -1;
- int use_vnet = 0;
- int mtu;
- const char *bridge = NULL;
- char iface[IFNAMSIZ];
- int index;
- ACLRule *acl_rule;
- ACLList acl_list;
- int access_allowed, access_denied;
- int ret = EXIT_SUCCESS;
-
-#ifdef CONFIG_LIBCAP
- /* if we're run from an suid binary, immediately drop privileges preserving
- * cap_net_admin */
- if (geteuid() == 0 && getuid() != geteuid()) {
- if (drop_privileges() == -1) {
- fprintf(stderr, "failed to drop privileges\n");
- return 1;
- }
- }
-#endif
-
- /* parse arguments */
- for (index = 1; index < argc; index++) {
- if (strcmp(argv[index], "--use-vnet") == 0) {
- use_vnet = 1;
- } else if (strncmp(argv[index], "--br=", 5) == 0) {
- bridge = &argv[index][5];
- } else if (strncmp(argv[index], "--fd=", 5) == 0) {
- unixfd = atoi(&argv[index][5]);
- } else {
- usage();
- return EXIT_FAILURE;
- }
- }
-
- if (bridge == NULL || unixfd == -1) {
- usage();
- return EXIT_FAILURE;
- }
-
- /* parse default acl file */
- QSIMPLEQ_INIT(&acl_list);
- if (parse_acl_file(DEFAULT_ACL_FILE, &acl_list) == -1) {
- fprintf(stderr, "failed to parse default acl file `%s'\n",
- DEFAULT_ACL_FILE);
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* validate bridge against acl -- default policy is to deny
- * according acl policy if we have a deny and allow both
- * then deny should always win over allow
- */
- access_allowed = 0;
- access_denied = 0;
- QSIMPLEQ_FOREACH(acl_rule, &acl_list, entry) {
- switch (acl_rule->type) {
- case ACL_ALLOW_ALL:
- access_allowed = 1;
- break;
- case ACL_ALLOW:
- if (strcmp(bridge, acl_rule->iface) == 0) {
- access_allowed = 1;
- }
- break;
- case ACL_DENY_ALL:
- access_denied = 1;
- break;
- case ACL_DENY:
- if (strcmp(bridge, acl_rule->iface) == 0) {
- access_denied = 1;
- }
- break;
- }
- }
-
- if ((access_allowed == 0) || (access_denied == 1)) {
- fprintf(stderr, "access denied by acl file\n");
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* open a socket to use to control the network interfaces */
- ctlfd = socket(AF_INET, SOCK_STREAM, 0);
- if (ctlfd == -1) {
- fprintf(stderr, "failed to open control socket: %s\n", strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* open the tap device */
- fd = open("/dev/net/tun", O_RDWR);
- if (fd == -1) {
- fprintf(stderr, "failed to open /dev/net/tun: %s\n", strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* request a tap device, disable PI, and add vnet header support if
- * requested and it's available. */
- prep_ifreq(&ifr, "tap%d");
- ifr.ifr_flags = IFF_TAP|IFF_NO_PI;
- if (use_vnet && has_vnet_hdr(fd)) {
- ifr.ifr_flags |= IFF_VNET_HDR;
- }
-
- if (ioctl(fd, TUNSETIFF, &ifr) == -1) {
- fprintf(stderr, "failed to create tun device: %s\n", strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* save tap device name */
- snprintf(iface, sizeof(iface), "%s", ifr.ifr_name);
-
- /* get the mtu of the bridge */
- prep_ifreq(&ifr, bridge);
- if (ioctl(ctlfd, SIOCGIFMTU, &ifr) == -1) {
- fprintf(stderr, "failed to get mtu of bridge `%s': %s\n",
- bridge, strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* save mtu */
- mtu = ifr.ifr_mtu;
-
- /* set the mtu of the interface based on the bridge */
- prep_ifreq(&ifr, iface);
- ifr.ifr_mtu = mtu;
- if (ioctl(ctlfd, SIOCSIFMTU, &ifr) == -1) {
- fprintf(stderr, "failed to set mtu of device `%s' to %d: %s\n",
- iface, mtu, strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* Linux uses the lowest enslaved MAC address as the MAC address of
- * the bridge. Set MAC address to a high value so that it doesn't
- * affect the MAC address of the bridge.
- */
- if (ioctl(ctlfd, SIOCGIFHWADDR, &ifr) < 0) {
- fprintf(stderr, "failed to get MAC address of device `%s': %s\n",
- iface, strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
- ifr.ifr_hwaddr.sa_data[0] = 0xFE;
- if (ioctl(ctlfd, SIOCSIFHWADDR, &ifr) < 0) {
- fprintf(stderr, "failed to set MAC address of device `%s': %s\n",
- iface, strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* add the interface to the bridge */
- prep_ifreq(&ifr, bridge);
- ifindex = if_nametoindex(iface);
-#ifndef SIOCBRADDIF
- ifargs[0] = BRCTL_ADD_IF;
- ifargs[1] = ifindex;
- ifargs[2] = 0;
- ifargs[3] = 0;
- ifr.ifr_data = (void *)ifargs;
- ret = ioctl(ctlfd, SIOCDEVPRIVATE, &ifr);
-#else
- ifr.ifr_ifindex = ifindex;
- ret = ioctl(ctlfd, SIOCBRADDIF, &ifr);
-#endif
- if (ret == -1) {
- fprintf(stderr, "failed to add interface `%s' to bridge `%s': %s\n",
- iface, bridge, strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* bring the interface up */
- prep_ifreq(&ifr, iface);
- if (ioctl(ctlfd, SIOCGIFFLAGS, &ifr) == -1) {
- fprintf(stderr, "failed to get interface flags for `%s': %s\n",
- iface, strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- ifr.ifr_flags |= IFF_UP;
- if (ioctl(ctlfd, SIOCSIFFLAGS, &ifr) == -1) {
- fprintf(stderr, "failed to bring up interface `%s': %s\n",
- iface, strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* write fd to the domain socket */
- if (send_fd(unixfd, fd) == -1) {
- fprintf(stderr, "failed to write fd to unix socket: %s\n",
- strerror(errno));
- ret = EXIT_FAILURE;
- goto cleanup;
- }
-
- /* ... */
-
- /* profit! */
-
-cleanup:
- if (fd >= 0) {
- close(fd);
- }
- if (ctlfd >= 0) {
- close(ctlfd);
- }
- while ((acl_rule = QSIMPLEQ_FIRST(&acl_list)) != NULL) {
- QSIMPLEQ_REMOVE_HEAD(&acl_list, entry);
- g_free(acl_rule);
- }
-
- return ret;
-}