From e49c629b22cc1eea89be4dbf6ef039706c143ab9 Mon Sep 17 00:00:00 2001 From: Toni Uhlig Date: Thu, 14 Dec 2017 15:42:19 +0100 Subject: ptunnel-ng: * fixed opt type for `-p` * `-l` argument is required * exported packet structs from ptunnel.h to pkt.h --- pkt.h | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+) create mode 100644 pkt.h (limited to 'pkt.h') diff --git a/pkt.h b/pkt.h new file mode 100644 index 0000000..22cd289 --- /dev/null +++ b/pkt.h @@ -0,0 +1,83 @@ +#ifndef PKT_H +#define PKT_H 1 + +#include + +#ifdef WIN32 +#include +typedef int socklen_t; +typedef uint32_t in_addr_t; +#define ETH_ALEN 6 /* Octets in one ethernet addr */ +struct ether_header { + u_int8_t ether_dhost[ETH_ALEN]; /* destination eth addr */ + u_int8_t ether_shost[ETH_ALEN]; /* source ether addr */ + u_int16_t ether_type; /* packet type ID field */ +}; +#endif /* WIN32 */ + +/** Resend packets after this interval (in seconds) */ +#define kResend_interval 1.5 + +/** ping_tunnel_pkt_t: This data structure represents the header of a ptunnel + * packet, consisting of a magic number, the tunnel's destination IP and port, + * as well as some other fields. Note that the dest IP and port is only valid + * in packets from the client to the proxy. + */ +typedef struct { + /** magic number, used to identify ptunnel packets. */ + uint32_t magic; + /** destination IP and port (used by proxy to figure */ + uint32_t dst_ip; + /** out where to tunnel to) */ + uint32_t dst_port; + /** current connection state; see constants above. */ + uint32_t state; + /** sequence number of last packet received from other end */ + uint32_t ack; + /** length of data buffer */ + uint32_t data_len; + /** sequence number of this packet */ + uint16_t seq_no; + /** id number, used to separate different tunnels from each other */ + uint16_t id_no; + /** optional data buffer */ + char data[0]; +} __attribute__ ((packed)) ping_tunnel_pkt_t; + +/** ip_packet_t: This is basically my own definition of the IP packet, which + * of course complies with the official definition ;) See any good book on IP + * (or even the RFC) for info on the contents of this packet. + */ +typedef struct { + uint8_t vers_ihl; + uint8_t tos; + uint16_t pkt_len; + uint16_t id; + uint16_t flags_frag_offset; + uint8_t ttl; + uint8_t proto; // 1 for ICMP + uint16_t checksum; + uint32_t src_ip; + uint32_t dst_ip; + char data[0]; +} __attribute__ ((packed)) ip_packet_t; + +/** icmp_echo_packet_t: This is the definition of a standard ICMP header. The + * ptunnel packets are constructed as follows: + * [ ip header (20 bytes) ] + * [ icmp header (8 bytes) ] + * [ ptunnel header (28 bytes) ] + * + * We actually only create the ICMP and ptunnel headers, the IP header is + * taken care of by the OS. + */ +typedef struct { + uint8_t type; + uint8_t code; + uint16_t checksum; + uint16_t identifier; + uint16_t seq; + char data[0]; +} __attribute__ ((packed)) icmp_echo_packet_t; + +#endif -- cgit v1.2.3