| 1 | /* |
| 2 | * Network proxy abstraction in PuTTY |
| 3 | * |
| 4 | * A proxy layer, if necessary, wedges itself between the |
| 5 | * network code and the higher level backend. |
| 6 | * |
| 7 | * Supported proxies: HTTP CONNECT, generic telnet |
| 8 | * In progress: SOCKS |
| 9 | */ |
| 10 | |
| 11 | #ifndef PUTTY_PROXY_H |
| 12 | #define PUTTY_PROXY_H |
| 13 | |
| 14 | #define PROXY_ERROR_GENERAL 8000 |
| 15 | #define PROXY_ERROR_UNEXPECTED 8001 |
| 16 | |
| 17 | typedef struct Socket_proxy_tag * Proxy_Socket; |
| 18 | |
| 19 | struct Socket_proxy_tag { |
| 20 | struct socket_function_table *fn; |
| 21 | /* the above variable absolutely *must* be the first in this structure */ |
| 22 | |
| 23 | char * error; |
| 24 | |
| 25 | Socket sub_socket; |
| 26 | Plug plug; |
| 27 | SockAddr remote_addr; |
| 28 | int remote_port; |
| 29 | |
| 30 | bufchain pending_output_data; |
| 31 | bufchain pending_oob_output_data; |
| 32 | int pending_flush; |
| 33 | bufchain pending_input_data; |
| 34 | |
| 35 | #define PROXY_STATE_NEW -1 |
| 36 | #define PROXY_STATE_ACTIVE 0 |
| 37 | |
| 38 | int state; /* proxy states greater than 0 are implementation |
| 39 | * dependent, but represent various stages/states |
| 40 | * of the initialization/setup/negotiation with the |
| 41 | * proxy server. |
| 42 | */ |
| 43 | int freeze; /* should we freeze the underlying socket when |
| 44 | * we are done with the proxy negotiation? this |
| 45 | * simply caches the value of sk_set_frozen calls. |
| 46 | */ |
| 47 | |
| 48 | #define PROXY_CHANGE_NEW -1 |
| 49 | #define PROXY_CHANGE_CLOSING 0 |
| 50 | #define PROXY_CHANGE_SENT 1 |
| 51 | #define PROXY_CHANGE_RECEIVE 2 |
| 52 | #define PROXY_CHANGE_ACCEPTING 3 |
| 53 | |
| 54 | /* something has changed (a call from the sub socket |
| 55 | * layer into our Proxy Plug layer, or we were just |
| 56 | * created, etc), so the proxy layer needs to handle |
| 57 | * this change (the type of which is the second argument) |
| 58 | * and further the proxy negotiation process. |
| 59 | */ |
| 60 | |
| 61 | int (*negotiate) (Proxy_Socket /* this */, int /* change type */); |
| 62 | |
| 63 | /* current arguments of plug handlers |
| 64 | * (for use by proxy's negotiate function) |
| 65 | */ |
| 66 | |
| 67 | /* closing */ |
| 68 | char *closing_error_msg; |
| 69 | int closing_error_code; |
| 70 | int closing_calling_back; |
| 71 | |
| 72 | /* receive */ |
| 73 | int receive_urgent; |
| 74 | char *receive_data; |
| 75 | int receive_len; |
| 76 | |
| 77 | /* sent */ |
| 78 | int sent_bufsize; |
| 79 | |
| 80 | /* accepting */ |
| 81 | void *accepting_sock; |
| 82 | |
| 83 | }; |
| 84 | |
| 85 | typedef struct Plug_proxy_tag * Proxy_Plug; |
| 86 | |
| 87 | struct Plug_proxy_tag { |
| 88 | struct plug_function_table *fn; |
| 89 | /* the above variable absolutely *must* be the first in this structure */ |
| 90 | |
| 91 | Proxy_Socket proxy_socket; |
| 92 | |
| 93 | }; |
| 94 | |
| 95 | extern void proxy_activate (Proxy_Socket); |
| 96 | |
| 97 | extern int proxy_http_negotiate (Proxy_Socket, int); |
| 98 | extern int proxy_telnet_negotiate (Proxy_Socket, int); |
| 99 | extern int proxy_socks_negotiate (Proxy_Socket, int); |
| 100 | |
| 101 | #endif |