Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com) |
| 3 | * Licensed under the GPL |
| 4 | */ |
| 5 | |
| 6 | #include <stdio.h> |
| 7 | #include <stddef.h> |
| 8 | #include <stdlib.h> |
| 9 | #include <unistd.h> |
| 10 | #include <errno.h> |
| 11 | #include <sys/wait.h> |
| 12 | #include <sys/socket.h> |
| 13 | #include <sys/un.h> |
| 14 | #include <sys/uio.h> |
| 15 | #include <sys/ioctl.h> |
| 16 | #include <net/if.h> |
| 17 | #include <linux/if_tun.h> |
| 18 | #include "net_user.h" |
| 19 | #include "tuntap.h" |
| 20 | #include "kern_util.h" |
| 21 | #include "user_util.h" |
| 22 | #include "user.h" |
| 23 | #include "helper.h" |
| 24 | #include "os.h" |
| 25 | |
| 26 | #define MAX_PACKET ETH_MAX_PACKET |
| 27 | |
| 28 | void tuntap_user_init(void *data, void *dev) |
| 29 | { |
| 30 | struct tuntap_data *pri = data; |
| 31 | |
| 32 | pri->dev = dev; |
| 33 | } |
| 34 | |
| 35 | static void tuntap_add_addr(unsigned char *addr, unsigned char *netmask, |
| 36 | void *data) |
| 37 | { |
| 38 | struct tuntap_data *pri = data; |
| 39 | |
| 40 | tap_check_ips(pri->gate_addr, addr); |
| 41 | if((pri->fd == -1) || pri->fixed_config) return; |
| 42 | open_addr(addr, netmask, pri->dev_name); |
| 43 | } |
| 44 | |
| 45 | static void tuntap_del_addr(unsigned char *addr, unsigned char *netmask, |
| 46 | void *data) |
| 47 | { |
| 48 | struct tuntap_data *pri = data; |
| 49 | |
| 50 | if((pri->fd == -1) || pri->fixed_config) return; |
| 51 | close_addr(addr, netmask, pri->dev_name); |
| 52 | } |
| 53 | |
| 54 | struct tuntap_pre_exec_data { |
| 55 | int stdout; |
| 56 | int close_me; |
| 57 | }; |
| 58 | |
| 59 | static void tuntap_pre_exec(void *arg) |
| 60 | { |
| 61 | struct tuntap_pre_exec_data *data = arg; |
| 62 | |
| 63 | dup2(data->stdout, 1); |
| 64 | os_close_file(data->close_me); |
| 65 | } |
| 66 | |
| 67 | static int tuntap_open_tramp(char *gate, int *fd_out, int me, int remote, |
| 68 | char *buffer, int buffer_len, int *used_out) |
| 69 | { |
| 70 | struct tuntap_pre_exec_data data; |
| 71 | char version_buf[sizeof("nnnnn\0")]; |
| 72 | char *argv[] = { "uml_net", version_buf, "tuntap", "up", gate, |
| 73 | NULL }; |
| 74 | char buf[CMSG_SPACE(sizeof(*fd_out))]; |
| 75 | struct msghdr msg; |
| 76 | struct cmsghdr *cmsg; |
| 77 | struct iovec iov; |
| 78 | int pid, n; |
| 79 | |
| 80 | sprintf(version_buf, "%d", UML_NET_VERSION); |
| 81 | |
| 82 | data.stdout = remote; |
| 83 | data.close_me = me; |
| 84 | |
| 85 | pid = run_helper(tuntap_pre_exec, &data, argv, NULL); |
| 86 | |
| 87 | if(pid < 0) return(-pid); |
| 88 | |
| 89 | os_close_file(remote); |
| 90 | |
| 91 | msg.msg_name = NULL; |
| 92 | msg.msg_namelen = 0; |
| 93 | if(buffer != NULL){ |
| 94 | iov = ((struct iovec) { buffer, buffer_len }); |
| 95 | msg.msg_iov = &iov; |
| 96 | msg.msg_iovlen = 1; |
| 97 | } |
| 98 | else { |
| 99 | msg.msg_iov = NULL; |
| 100 | msg.msg_iovlen = 0; |
| 101 | } |
| 102 | msg.msg_control = buf; |
| 103 | msg.msg_controllen = sizeof(buf); |
| 104 | msg.msg_flags = 0; |
| 105 | n = recvmsg(me, &msg, 0); |
| 106 | *used_out = n; |
| 107 | if(n < 0){ |
| 108 | printk("tuntap_open_tramp : recvmsg failed - errno = %d\n", |
| 109 | errno); |
| 110 | return(-errno); |
| 111 | } |
| 112 | CATCH_EINTR(waitpid(pid, NULL, 0)); |
| 113 | |
| 114 | cmsg = CMSG_FIRSTHDR(&msg); |
| 115 | if(cmsg == NULL){ |
| 116 | printk("tuntap_open_tramp : didn't receive a message\n"); |
| 117 | return(-EINVAL); |
| 118 | } |
| 119 | if((cmsg->cmsg_level != SOL_SOCKET) || |
| 120 | (cmsg->cmsg_type != SCM_RIGHTS)){ |
| 121 | printk("tuntap_open_tramp : didn't receive a descriptor\n"); |
| 122 | return(-EINVAL); |
| 123 | } |
| 124 | *fd_out = ((int *) CMSG_DATA(cmsg))[0]; |
| 125 | return(0); |
| 126 | } |
| 127 | |
| 128 | static int tuntap_open(void *data) |
| 129 | { |
| 130 | struct ifreq ifr; |
| 131 | struct tuntap_data *pri = data; |
| 132 | char *output, *buffer; |
| 133 | int err, fds[2], len, used; |
| 134 | |
| 135 | err = tap_open_common(pri->dev, pri->gate_addr); |
| 136 | if(err < 0) |
| 137 | return(err); |
| 138 | |
| 139 | if(pri->fixed_config){ |
| 140 | pri->fd = os_open_file("/dev/net/tun", of_rdwr(OPENFLAGS()), 0); |
| 141 | if(pri->fd < 0){ |
| 142 | printk("Failed to open /dev/net/tun, err = %d\n", |
| 143 | -pri->fd); |
| 144 | return(pri->fd); |
| 145 | } |
| 146 | memset(&ifr, 0, sizeof(ifr)); |
| 147 | ifr.ifr_flags = IFF_TAP | IFF_NO_PI; |
| 148 | strlcpy(ifr.ifr_name, pri->dev_name, sizeof(ifr.ifr_name)); |
| 149 | if(ioctl(pri->fd, TUNSETIFF, (void *) &ifr) < 0){ |
| 150 | printk("TUNSETIFF failed, errno = %d\n", errno); |
| 151 | os_close_file(pri->fd); |
| 152 | return(-errno); |
| 153 | } |
| 154 | } |
| 155 | else { |
| 156 | err = os_pipe(fds, 0, 0); |
| 157 | if(err < 0){ |
| 158 | printk("tuntap_open : os_pipe failed - err = %d\n", |
| 159 | -err); |
| 160 | return(err); |
| 161 | } |
| 162 | |
| 163 | buffer = get_output_buffer(&len); |
| 164 | if(buffer != NULL) len--; |
| 165 | used = 0; |
| 166 | |
| 167 | err = tuntap_open_tramp(pri->gate_addr, &pri->fd, fds[0], |
| 168 | fds[1], buffer, len, &used); |
| 169 | |
| 170 | output = buffer; |
| 171 | if(err < 0) { |
| 172 | printk("%s", output); |
| 173 | free_output_buffer(buffer); |
| 174 | printk("tuntap_open_tramp failed - err = %d\n", -err); |
| 175 | return(err); |
| 176 | } |
| 177 | |
| 178 | pri->dev_name = uml_strdup(buffer); |
| 179 | output += IFNAMSIZ; |
| 180 | printk("%s", output); |
| 181 | free_output_buffer(buffer); |
| 182 | |
| 183 | os_close_file(fds[0]); |
| 184 | iter_addresses(pri->dev, open_addr, pri->dev_name); |
| 185 | } |
| 186 | |
| 187 | return(pri->fd); |
| 188 | } |
| 189 | |
| 190 | static void tuntap_close(int fd, void *data) |
| 191 | { |
| 192 | struct tuntap_data *pri = data; |
| 193 | |
| 194 | if(!pri->fixed_config) |
| 195 | iter_addresses(pri->dev, close_addr, pri->dev_name); |
| 196 | os_close_file(fd); |
| 197 | pri->fd = -1; |
| 198 | } |
| 199 | |
| 200 | static int tuntap_set_mtu(int mtu, void *data) |
| 201 | { |
| 202 | return(mtu); |
| 203 | } |
| 204 | |
| 205 | struct net_user_info tuntap_user_info = { |
| 206 | .init = tuntap_user_init, |
| 207 | .open = tuntap_open, |
| 208 | .close = tuntap_close, |
| 209 | .remove = NULL, |
| 210 | .set_mtu = tuntap_set_mtu, |
| 211 | .add_address = tuntap_add_addr, |
| 212 | .delete_address = tuntap_del_addr, |
| 213 | .max_packet = MAX_PACKET |
| 214 | }; |
| 215 | |
| 216 | /* |
| 217 | * Overrides for Emacs so that we follow Linus's tabbing style. |
| 218 | * Emacs will notice this stuff at the end of the file and automatically |
| 219 | * adjust the settings for this buffer only. This must remain at the end |
| 220 | * of the file. |
| 221 | * --------------------------------------------------------------------------- |
| 222 | * Local variables: |
| 223 | * c-file-style: "linux" |
| 224 | * End: |
| 225 | */ |