X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/fab893b6cac31863187aed38740cb302a3c42193..055817455466c8eb60392f30bb7c689763962e17:/portfwd.c diff --git a/portfwd.c b/portfwd.c index 8ef1761b..1239f671 100644 --- a/portfwd.c +++ b/portfwd.c @@ -86,7 +86,7 @@ struct PFwdPrivate { int buflen; }; -static int pfd_closing(Plug plug, char *error_msg, int error_code, +static int pfd_closing(Plug plug, const char *error_msg, int error_code, int calling_back) { struct PFwdPrivate *pr = (struct PFwdPrivate *) plug; @@ -107,7 +107,12 @@ static int pfd_receive(Plug plug, int urgent, char *data, int len) struct PFwdPrivate *pr = (struct PFwdPrivate *) plug; if (pr->dynamic) { while (len--) { + /* + * Throughout SOCKS negotiation, "hostname" is re-used as a + * random protocol buffer with "port" storing the length. + */ if (pr->port >= lenof(pr->hostname)) { + /* Request too long. */ if ((pr->dynamic >> 12) == 4) { /* Send back a SOCKS 4 error before closing. */ char data[8]; @@ -133,6 +138,7 @@ static int pfd_receive(Plug plug, int urgent, char *data, int len) pr->dynamic = 0x4000; if (pr->port < 2) continue;/* don't have command code yet */ if (pr->hostname[1] != 1) { + /* Not CONNECT. */ /* Send back a SOCKS 4 error before closing. */ char data[8]; memset(data, 0, sizeof(data)); @@ -141,9 +147,9 @@ static int pfd_receive(Plug plug, int urgent, char *data, int len) pfd_close(pr->s); return 1; } - if (pr->port < 8) continue; /* haven't started username */ + if (pr->port <= 8) continue; /* haven't started user/hostname */ if (pr->hostname[pr->port-1] != 0) - continue; /* haven't _finished_ username */ + continue; /* haven't _finished_ user/hostname */ /* * Now we have a full SOCKS 4 request. Check it to * see if it's a SOCKS 4A request. @@ -165,7 +171,7 @@ static int pfd_receive(Plug plug, int urgent, char *data, int len) pr->hostname[0] = 0; /* reply version code */ pr->hostname[1] = 90; /* request granted */ sk_write(pr->s, pr->hostname, 8); - len= pr->port; + len= pr->port - 8; pr->port = GET_16BIT_MSB_FIRST(pr->hostname+2); memmove(pr->hostname, pr->hostname + 8, len); goto connect; @@ -220,7 +226,23 @@ static int pfd_receive(Plug plug, int urgent, char *data, int len) } if (pr->dynamic == 0x5001) { - int atype, alen; + /* + * We're receiving a SOCKS request. + */ + unsigned char reply[10]; /* SOCKS5 atyp=1 reply */ + int atype, alen = 0; + + /* + * Pre-fill reply packet. + * In all cases, we set BND.{HOST,ADDR} to 0.0.0.0:0 + * (atyp=1) in the reply; if we succeed, we don't know + * the right answers, and if we fail, they should be + * ignored. + */ + memset(reply, 0, lenof(reply)); + reply[0] = 5; /* VER */ + reply[3] = 1; /* ATYP = 1 (IPv4, 0.0.0.0:0) */ + if (pr->port < 6) continue; atype = (unsigned char)pr->hostname[3]; if (atype == 1) /* IPv4 address */ @@ -231,9 +253,9 @@ static int pfd_receive(Plug plug, int urgent, char *data, int len) alen = 1 + (unsigned char)pr->hostname[4]; if (pr->port < 6 + alen) continue; if (pr->hostname[1] != 1 || pr->hostname[2] != 0) { - pr->hostname[1] = 1; /* generic failure */ - pr->hostname[2] = 0; /* reserved */ - sk_write(pr->s, pr->hostname, pr->port); + /* Not CONNECT or reserved field nonzero - error */ + reply[1] = 1; /* generic failure */ + sk_write(pr->s, (char *) reply, lenof(reply)); pfd_close(pr->s); return 1; } @@ -243,8 +265,8 @@ static int pfd_receive(Plug plug, int urgent, char *data, int len) */ pr->port = GET_16BIT_MSB_FIRST(pr->hostname+4+alen); if (atype == 1) { - pr->hostname[1] = 0; /* succeeded */ - sk_write(pr->s, pr->hostname, alen + 6); + /* REP=0 (success) already */ + sk_write(pr->s, (char *) reply, lenof(reply)); sprintf(pr->hostname, "%d.%d.%d.%d", (unsigned char)pr->hostname[4], (unsigned char)pr->hostname[5], @@ -252,8 +274,8 @@ static int pfd_receive(Plug plug, int urgent, char *data, int len) (unsigned char)pr->hostname[7]); goto connect; } else if (atype == 3) { - pr->hostname[1] = 0; /* succeeded */ - sk_write(pr->s, pr->hostname, alen + 6); + /* REP=0 (success) already */ + sk_write(pr->s, (char *) reply, lenof(reply)); memmove(pr->hostname, pr->hostname + 5, alen-1); pr->hostname[alen-1] = '\0'; goto connect; @@ -261,14 +283,14 @@ static int pfd_receive(Plug plug, int urgent, char *data, int len) /* * Unknown address type. (FIXME: support IPv6!) */ - pr->hostname[1] = 8; /* atype not supported */ - sk_write(pr->s, pr->hostname, pr->port); + reply[1] = 8; /* atype not supported */ + sk_write(pr->s, (char *) reply, lenof(reply)); pfd_close(pr->s); - return 1; + return 1; } } } - + /* * If we get here without either having done `continue' * or `goto connect', it must be because there is no @@ -331,8 +353,8 @@ static void pfd_sent(Plug plug, int bufsize) /* * Called when receiving a PORT OPEN from the server */ -char *pfd_newconnect(Socket *s, char *hostname, int port, void *c, - const Config *cfg) +const char *pfd_newconnect(Socket *s, char *hostname, int port, + void *c, const Config *cfg, int addressfamily) { static const struct plug_function_table fn_table = { pfd_closing, @@ -342,15 +364,18 @@ char *pfd_newconnect(Socket *s, char *hostname, int port, void *c, }; SockAddr addr; - char *err, *dummy_realhost; + const char *err; + char *dummy_realhost; struct PFwdPrivate *pr; /* * Try to find host. */ - addr = name_lookup(hostname, port, &dummy_realhost, cfg); - if ((err = sk_addr_error(addr)) != NULL) + addr = name_lookup(hostname, port, &dummy_realhost, cfg, addressfamily); + if ((err = sk_addr_error(addr)) != NULL) { + sk_addr_free(addr); return err; + } /* * Open socket. @@ -362,16 +387,16 @@ char *pfd_newconnect(Socket *s, char *hostname, int port, void *c, pr->ready = 1; pr->c = c; pr->backhandle = NULL; /* we shouldn't need this */ + pr->dynamic = 0; pr->s = *s = new_connection(addr, dummy_realhost, port, - 0, 1, 0, (Plug) pr, cfg); + 0, 1, 0, 0, (Plug) pr, cfg); if ((err = sk_socket_error(*s)) != NULL) { sfree(pr); return err; } sk_set_private_ptr(*s, pr); - sk_addr_free(addr); return NULL; } @@ -379,7 +404,7 @@ char *pfd_newconnect(Socket *s, char *hostname, int port, void *c, called when someone connects to the local port */ -static int pfd_accepting(Plug p, void *sock) +static int pfd_accepting(Plug p, OSSocket sock) { static const struct plug_function_table fn_table = { pfd_closing, @@ -389,7 +414,7 @@ static int pfd_accepting(Plug p, void *sock) }; struct PFwdPrivate *pr, *org; Socket s; - char *err; + const char *err; org = (struct PFwdPrivate *)p; pr = snew(struct PFwdPrivate); @@ -412,9 +437,10 @@ static int pfd_accepting(Plug p, void *sock) if (org->dynamic) { pr->dynamic = 1; - pr->port = 0; /* hostname buffer is so far empty */ + pr->port = 0; /* "hostname" buffer is so far empty */ sk_set_frozen(s, 0); /* we want to receive SOCKS _now_! */ } else { + pr->dynamic = 0; strcpy(pr->hostname, org->hostname); pr->port = org->port; pr->c = new_sock_channel(org->backhandle, s); @@ -435,8 +461,9 @@ static int pfd_accepting(Plug p, void *sock) /* Add a new forwarding from port -> desthost:destport sets up a listener on the local machine on (srcaddr:)port */ -char *pfd_addforward(char *desthost, int destport, char *srcaddr, int port, - void *backhandle, const Config *cfg) +const char *pfd_addforward(char *desthost, int destport, char *srcaddr, + int port, void *backhandle, const Config *cfg, + void **sockdata, int address_family) { static const struct plug_function_table fn_table = { pfd_closing, @@ -445,7 +472,7 @@ char *pfd_addforward(char *desthost, int destport, char *srcaddr, int port, pfd_accepting }; - char *err; + const char *err; struct PFwdPrivate *pr; Socket s; @@ -467,7 +494,7 @@ char *pfd_addforward(char *desthost, int destport, char *srcaddr, int port, pr->backhandle = backhandle; pr->s = s = new_listener(srcaddr, port, (Plug) pr, - !cfg->lport_acceptall, cfg); + !cfg->lport_acceptall, cfg, address_family); if ((err = sk_socket_error(s)) != NULL) { sfree(pr); return err; @@ -475,6 +502,8 @@ char *pfd_addforward(char *desthost, int destport, char *srcaddr, int port, sk_set_private_ptr(s, pr); + *sockdata = (void *)s; + return NULL; } @@ -493,6 +522,14 @@ void pfd_close(Socket s) sk_close(s); } +/* + * Terminate a listener. + */ +void pfd_terminate(void *sv) +{ + pfd_close((Socket)sv); +} + void pfd_unthrottle(Socket s) { struct PFwdPrivate *pr;