X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/01c034ad857128c51482a563befb374e38ebe668..32874aeac8dacbca26663777b39a79efc5d8dc4b:/x11fwd.c diff --git a/x11fwd.c b/x11fwd.c index 2b4a6bc5..5be69b86 100644 --- a/x11fwd.c +++ b/x11fwd.c @@ -64,49 +64,53 @@ extern void sshfwd_write(void *, char *, int); struct X11Private { struct plug_function_table *fn; /* the above variable absolutely *must* be the first in this structure */ - unsigned char firstpkt[12]; /* first X data packet */ + unsigned char firstpkt[12]; /* first X data packet */ char *auth_protocol; unsigned char *auth_data; int data_read, auth_plen, auth_psize, auth_dlen, auth_dsize; int verified; - void *c; /* data used by ssh.c */ + void *c; /* data used by ssh.c */ Socket s; }; -void x11_close (Socket s); +void x11_close(Socket s); static unsigned char x11_authdata[64]; static int x11_authdatalen; void x11_invent_auth(char *proto, int protomaxlen, - char *data, int datamaxlen) { + char *data, int datamaxlen) +{ char ourdata[64]; int i; /* MIT-MAGIC-COOKIE-1. Cookie size is 128 bits (16 bytes). */ x11_authdatalen = 16; for (i = 0; i < 16; i++) - x11_authdata[i] = random_byte(); + x11_authdata[i] = random_byte(); /* Now format for the recipient. */ strncpy(proto, "MIT-MAGIC-COOKIE-1", protomaxlen); ourdata[0] = '\0'; for (i = 0; i < x11_authdatalen; i++) - sprintf(ourdata+strlen(ourdata), "%02x", x11_authdata[i]); + sprintf(ourdata + strlen(ourdata), "%02x", x11_authdata[i]); strncpy(data, ourdata, datamaxlen); } -static int x11_verify(char *proto, unsigned char *data, int dlen) { +static int x11_verify(char *proto, unsigned char *data, int dlen) +{ if (strcmp(proto, "MIT-MAGIC-COOKIE-1") != 0) - return 0; /* wrong protocol attempted */ + return 0; /* wrong protocol attempted */ if (dlen != x11_authdatalen) - return 0; /* cookie was wrong length */ + return 0; /* cookie was wrong length */ if (memcmp(x11_authdata, data, dlen) != 0) - return 0; /* cookie was wrong cookie! */ + return 0; /* cookie was wrong cookie! */ return 1; } -static int x11_closing (Plug plug, char *error_msg, int error_code, int calling_back) { +static int x11_closing(Plug plug, char *error_msg, int error_code, + int calling_back) +{ struct X11Private *pr = (struct X11Private *) plug; /* @@ -119,7 +123,8 @@ static int x11_closing (Plug plug, char *error_msg, int error_code, int calling_ return 1; } -static int x11_receive (Plug plug, int urgent, char *data, int len) { +static int x11_receive(Plug plug, int urgent, char *data, int len) +{ struct X11Private *pr = (struct X11Private *) plug; sshfwd_write(pr->c, data, len); @@ -132,7 +137,8 @@ static int x11_receive (Plug plug, int urgent, char *data, int len) { * Returns an error message, or NULL on success. * also, fills the SocketsStructure */ -char *x11_init (Socket *s, char *display, void *c) { +char *x11_init(Socket * s, char *display, void *c) +{ static struct plug_function_table fn_table = { x11_closing, x11_receive @@ -150,11 +156,11 @@ char *x11_init (Socket *s, char *display, void *c) { */ n = strcspn(display, ":"); if (display[n]) - displaynum = atoi(display+n+1); + displaynum = atoi(display + n + 1); else - displaynum = 0; /* sensible default */ - if (n > sizeof(host)-1) - n = sizeof(host)-1; + displaynum = 0; /* sensible default */ + if (n > sizeof(host) - 1) + n = sizeof(host) - 1; strncpy(host, display, n); host[n] = '\0'; @@ -162,7 +168,7 @@ char *x11_init (Socket *s, char *display, void *c) { * Try to find host. */ addr = sk_namelookup(host, &dummy_realhost); - if ( (err = sk_addr_error(addr)) ) + if ((err = sk_addr_error(addr))) return err; port = 6000 + displaynum; @@ -170,7 +176,7 @@ char *x11_init (Socket *s, char *display, void *c) { /* * Open socket. */ - pr = (struct X11Private *)smalloc(sizeof(struct X11Private)); + pr = (struct X11Private *) smalloc(sizeof(struct X11Private)); pr->fn = &fn_table; pr->auth_protocol = NULL; pr->verified = 0; @@ -178,8 +184,8 @@ char *x11_init (Socket *s, char *display, void *c) { pr->c = c; pr->s = *s = sk_new(addr, port, 0, 1, (Plug) pr); - if ( (err = sk_socket_error(*s)) ) { - sfree (pr); + if ((err = sk_socket_error(*s))) { + sfree(pr); return err; } @@ -188,15 +194,16 @@ char *x11_init (Socket *s, char *display, void *c) { return NULL; } -void x11_close (Socket s) { - struct X11Private *pr; - if (!s) - return; - pr = (struct X11Private *)sk_get_private_ptr(s); +void x11_close(Socket s) +{ + struct X11Private *pr; + if (!s) + return; + pr = (struct X11Private *) sk_get_private_ptr(s); if (pr->auth_protocol) { - sfree(pr->auth_protocol); - sfree(pr->auth_data); + sfree(pr->auth_protocol); + sfree(pr->auth_data); } sfree(pr); @@ -207,8 +214,9 @@ void x11_close (Socket s) { /* * Called to send data down the raw connection. */ -void x11_send (Socket s, char *data, int len) { - struct X11Private *pr = (struct X11Private *)sk_get_private_ptr(s); +void x11_send(Socket s, char *data, int len) +{ + struct X11Private *pr = (struct X11Private *) sk_get_private_ptr(s); if (s == NULL) return; @@ -217,74 +225,74 @@ void x11_send (Socket s, char *data, int len) { * Read the first packet. */ while (len > 0 && pr->data_read < 12) - pr->firstpkt[pr->data_read++] = (unsigned char)(len--, *data++); + pr->firstpkt[pr->data_read++] = (unsigned char) (len--, *data++); if (pr->data_read < 12) - return; + return; /* * If we have not allocated the auth_protocol and auth_data * strings, do so now. */ if (!pr->auth_protocol) { - pr->auth_plen = GET_16BIT(pr->firstpkt[0], pr->firstpkt+6); - pr->auth_dlen = GET_16BIT(pr->firstpkt[0], pr->firstpkt+8); - pr->auth_psize = (pr->auth_plen + 3) &~ 3; - pr->auth_dsize = (pr->auth_dlen + 3) &~ 3; - /* Leave room for a terminating zero, to make our lives easier. */ - pr->auth_protocol = (char *)smalloc(pr->auth_psize+1); - pr->auth_data = (char *)smalloc(pr->auth_dsize); + pr->auth_plen = GET_16BIT(pr->firstpkt[0], pr->firstpkt + 6); + pr->auth_dlen = GET_16BIT(pr->firstpkt[0], pr->firstpkt + 8); + pr->auth_psize = (pr->auth_plen + 3) & ~3; + pr->auth_dsize = (pr->auth_dlen + 3) & ~3; + /* Leave room for a terminating zero, to make our lives easier. */ + pr->auth_protocol = (char *) smalloc(pr->auth_psize + 1); + pr->auth_data = (char *) smalloc(pr->auth_dsize); } /* * Read the auth_protocol and auth_data strings. */ while (len > 0 && pr->data_read < 12 + pr->auth_psize) - pr->auth_protocol[pr->data_read++ - 12] = (len--, *data++); + pr->auth_protocol[pr->data_read++ - 12] = (len--, *data++); while (len > 0 && pr->data_read < 12 + pr->auth_psize + pr->auth_dsize) - pr->auth_data[pr->data_read++ - 12 - - pr->auth_psize] = (unsigned char)(len--, *data++); + pr->auth_data[pr->data_read++ - 12 - + pr->auth_psize] = (unsigned char) (len--, *data++); if (pr->data_read < 12 + pr->auth_psize + pr->auth_dsize) - return; + return; /* * If we haven't verified the authentication, do so now. */ if (!pr->verified) { - int ret; - - pr->auth_protocol[pr->auth_plen] = '\0'; /* ASCIZ */ - ret = x11_verify(pr->auth_protocol, pr->auth_data, pr->auth_dlen); - - /* - * If authentication failed, construct and send an error - * packet, then terminate the connection. - */ - if (!ret) { - char message[] = "Authentication failed at PuTTY X11 proxy"; - unsigned char reply[8 + sizeof(message) + 4]; - int msglen = sizeof(message)-1; /* skip zero byte */ - int msgsize = (msglen+3) &~ 3; - reply[0] = 0; /* failure */ - reply[1] = msglen; /* length of reason string */ - memcpy(reply+2, pr->firstpkt+2, 4); /* major/minor proto vsn */ - PUT_16BIT(pr->firstpkt[0], reply+6, msglen >> 2); /* data len */ - memset(reply+8, 0, msgsize); - memcpy(reply+8, message, msglen); - sshfwd_write(pr->c, reply, 8+msgsize); - sshfwd_close(pr->c); - x11_close(s); - return; - } - - /* - * Now we know we're going to accept the connection. Strip - * the auth data. (TODO: if we ever work out how, we should - * replace some real auth data in here.) - */ - PUT_16BIT(pr->firstpkt[0], pr->firstpkt+6, 0); /* auth proto */ - PUT_16BIT(pr->firstpkt[0], pr->firstpkt+8, 0); /* auth data */ - sk_write(s, pr->firstpkt, 12); - pr->verified = 1; + int ret; + + pr->auth_protocol[pr->auth_plen] = '\0'; /* ASCIZ */ + ret = x11_verify(pr->auth_protocol, pr->auth_data, pr->auth_dlen); + + /* + * If authentication failed, construct and send an error + * packet, then terminate the connection. + */ + if (!ret) { + char message[] = "Authentication failed at PuTTY X11 proxy"; + unsigned char reply[8 + sizeof(message) + 4]; + int msglen = sizeof(message) - 1; /* skip zero byte */ + int msgsize = (msglen + 3) & ~3; + reply[0] = 0; /* failure */ + reply[1] = msglen; /* length of reason string */ + memcpy(reply + 2, pr->firstpkt + 2, 4); /* major/minor proto vsn */ + PUT_16BIT(pr->firstpkt[0], reply + 6, msglen >> 2); /* data len */ + memset(reply + 8, 0, msgsize); + memcpy(reply + 8, message, msglen); + sshfwd_write(pr->c, reply, 8 + msgsize); + sshfwd_close(pr->c); + x11_close(s); + return; + } + + /* + * Now we know we're going to accept the connection. Strip + * the auth data. (TODO: if we ever work out how, we should + * replace some real auth data in here.) + */ + PUT_16BIT(pr->firstpkt[0], pr->firstpkt + 6, 0); /* auth proto */ + PUT_16BIT(pr->firstpkt[0], pr->firstpkt + 8, 0); /* auth data */ + sk_write(s, pr->firstpkt, 12); + pr->verified = 1; } /*