diff options
Diffstat (limited to 'clatd.c')
-rw-r--r-- | clatd.c | 81 |
1 files changed, 35 insertions, 46 deletions
@@ -51,6 +51,7 @@ #include "getaddr.h" #include "dump.h" #include "tun.h" +#include "ring.h" #define DEVICENAME4 "clat4" @@ -229,13 +230,10 @@ void open_sockets(struct tun_data *tunnel, uint32_t mark) { tunnel->write_fd6 = rawsock; - int packetsock = socket(AF_PACKET, SOCK_DGRAM, htons(ETH_P_IPV6)); - if (packetsock < 0) { - logmsg(ANDROID_LOG_FATAL, "packet socket failed: %s", strerror(errno)); + tunnel->read_fd6 = ring_create(tunnel); + if (tunnel->read_fd6 < 0) { exit(1); } - - tunnel->read_fd6 = packetsock; } /* function: configure_interface @@ -282,16 +280,16 @@ void configure_interface(const char *uplink_interface, const char *plat_prefix, } /* function: read_packet - * reads a packet from the tunnel fd and passes it down the stack - * active_fd - tun file descriptor marked ready for reading - * tunnel - tun device data + * reads a packet from the tunnel fd and translates it + * read_fd - file descriptor to read original packet from + * write_fd - file descriptor to write translated packet to + * to_ipv6 - whether the packet is to be translated to ipv6 or ipv4 */ -void read_packet(int active_fd, const struct tun_data *tunnel) { +void read_packet(int read_fd, int write_fd, int to_ipv6) { ssize_t readlen; uint8_t buf[PACKETLEN], *packet; - int fd; - readlen = read(active_fd, buf, PACKETLEN); + readlen = read(read_fd, buf, PACKETLEN); if(readlen < 0) { logmsg(ANDROID_LOG_WARN,"read_packet/read error: %s", strerror(errno)); @@ -302,41 +300,32 @@ void read_packet(int active_fd, const struct tun_data *tunnel) { return; } - if (active_fd == tunnel->fd4) { - ssize_t header_size = sizeof(struct tun_pi); - - if (readlen < header_size) { - logmsg(ANDROID_LOG_WARN,"read_packet/short read: got %ld bytes", readlen); - return; - } - - struct tun_pi *tun_header = (struct tun_pi *) buf; - uint16_t proto = ntohs(tun_header->proto); - if (proto != ETH_P_IP) { - logmsg(ANDROID_LOG_WARN, "%s: unknown packet type = 0x%x", __func__, proto); - return; - } + struct tun_pi *tun_header = (struct tun_pi *) buf; + if (readlen < (ssize_t) sizeof(*tun_header)) { + logmsg(ANDROID_LOG_WARN,"read_packet/short read: got %ld bytes", readlen); + return; + } - if(tun_header->flags != 0) { - logmsg(ANDROID_LOG_WARN, "%s: unexpected flags = %d", __func__, tun_header->flags); - } + uint16_t proto = ntohs(tun_header->proto); + if (proto != ETH_P_IP) { + logmsg(ANDROID_LOG_WARN, "%s: unknown packet type = 0x%x", __func__, proto); + return; + } - fd = tunnel->write_fd6; - packet = buf + header_size; - readlen -= header_size; - } else { - fd = tunnel->fd4; - packet = buf; + if(tun_header->flags != 0) { + logmsg(ANDROID_LOG_WARN, "%s: unexpected flags = %d", __func__, tun_header->flags); } - translate_packet(fd, (fd == tunnel->write_fd6), packet, readlen); + packet = (uint8_t *) (tun_header + 1); + readlen -= sizeof(*tun_header); + translate_packet(write_fd, to_ipv6, packet, readlen); } /* function: event_loop * reads packets from the tun network interface and passes them down the stack * tunnel - tun device data */ -void event_loop(const struct tun_data *tunnel) { +void event_loop(struct tun_data *tunnel) { time_t last_interface_poll; struct pollfd wait_fd[] = { { tunnel->read_fd6, POLLIN, 0 }, @@ -352,16 +341,16 @@ void event_loop(const struct tun_data *tunnel) { logmsg(ANDROID_LOG_WARN,"event_loop/poll returned an error: %s",strerror(errno)); } } else { - size_t i; - for(i = 0; i < ARRAY_SIZE(wait_fd); i++) { - // Call read_packet if the socket has data to be read, but also if an - // error is waiting. If we don't call read() after getting POLLERR, a - // subsequent poll() will return immediately with POLLERR again, - // causing this code to spin in a loop. Calling read() will clear the - // socket error flag instead. - if(wait_fd[i].revents != 0) { - read_packet(wait_fd[i].fd,tunnel); - } + // Call read_packet if the socket has data to be read, but also if an + // error is waiting. If we don't call read() after getting POLLERR, a + // subsequent poll() will return immediately with POLLERR again, + // causing this code to spin in a loop. Calling read() will clear the + // socket error flag instead. + if (wait_fd[0].revents) { + ring_read(&tunnel->ring, tunnel->fd4, 0 /* to_ipv6 */); + } + if (wait_fd[1].revents) { + read_packet(tunnel->fd4, tunnel->write_fd6, 1 /* to_ipv6 */); } } |