diff options
Diffstat (limited to 'x11disp.c')
| -rw-r--r-- | x11disp.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/x11disp.c b/x11disp.c new file mode 100644 index 00000000..1dbc9c07 --- /dev/null +++ b/x11disp.c @@ -0,0 +1,189 @@ +/* + * Functions to manage an X11Display structure, by creating one from + * an ordinary display name string, and freeing one. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <assert.h> +#include <time.h> + +#include "putty.h" +#include "ssh.h" +#include "ssh/channel.h" +#include "tree234.h" + +struct X11Display *x11_setup_display(const char *display, Conf *conf, + char **error_msg) +{ + struct X11Display *disp = snew(struct X11Display); + char *localcopy; + + *error_msg = NULL; + + if (!display || !*display) { + localcopy = platform_get_x_display(); + if (!localcopy || !*localcopy) { + sfree(localcopy); + localcopy = dupstr(":0"); /* plausible default for any platform */ + } + } else + localcopy = dupstr(display); + + /* + * Parse the display name. + * + * We expect this to have one of the following forms: + * + * - the standard X format which looks like + * [ [ protocol '/' ] host ] ':' displaynumber [ '.' screennumber ] + * (X11 also permits a double colon to indicate DECnet, but + * that's not our problem, thankfully!) + * + * - only seen in the wild on MacOS (so far): a pathname to a + * Unix-domain socket, which will typically and confusingly + * end in ":0", and which I'm currently distinguishing from + * the standard scheme by noting that it starts with '/'. + */ + if (localcopy[0] == '/') { + disp->unixsocketpath = localcopy; + disp->unixdomain = true; + disp->hostname = NULL; + disp->displaynum = -1; + disp->screennum = 0; + disp->addr = NULL; + } else { + char *colon, *dot, *slash; + char *protocol, *hostname; + + colon = host_strrchr(localcopy, ':'); + if (!colon) { + *error_msg = dupprintf("display name '%s' has no ':number'" + " suffix", localcopy); + + sfree(disp); + sfree(localcopy); + return NULL; + } + + *colon++ = '\0'; + dot = strchr(colon, '.'); + if (dot) + *dot++ = '\0'; + + disp->displaynum = atoi(colon); + if (dot) + disp->screennum = atoi(dot); + else + disp->screennum = 0; + + protocol = NULL; + hostname = localcopy; + if (colon > localcopy) { + slash = strchr(localcopy, '/'); + if (slash) { + *slash++ = '\0'; + protocol = localcopy; + hostname = slash; + } + } + + disp->hostname = *hostname ? dupstr(hostname) : NULL; + + if (protocol) + disp->unixdomain = (!strcmp(protocol, "local") || + !strcmp(protocol, "unix")); + else if (!*hostname || !strcmp(hostname, "unix")) + disp->unixdomain = platform_uses_x11_unix_by_default; + else + disp->unixdomain = false; + + if (!disp->hostname && !disp->unixdomain) + disp->hostname = dupstr("localhost"); + + disp->unixsocketpath = NULL; + disp->addr = NULL; + + sfree(localcopy); + } + + /* + * Look up the display hostname, if we need to. + */ + if (!disp->unixdomain) { + const char *err; + + disp->port = 6000 + disp->displaynum; + disp->addr = name_lookup(disp->hostname, disp->port, + &disp->realhost, conf, ADDRTYPE_UNSPEC, + NULL, NULL); + + if ((err = sk_addr_error(disp->addr)) != NULL) { + *error_msg = dupprintf("unable to resolve host name '%s' in " + "display name", disp->hostname); + + sk_addr_free(disp->addr); + sfree(disp->hostname); + sfree(disp->unixsocketpath); + sfree(disp); + return NULL; + } + } + + /* + * Try upgrading an IP-style localhost display to a Unix-socket + * display (as the standard X connection libraries do). + */ + if (!disp->unixdomain && sk_address_is_local(disp->addr)) { + SockAddr *ux = platform_get_x11_unix_address(NULL, disp->displaynum); + const char *err = sk_addr_error(ux); + if (!err) { + /* Create trial connection to see if there is a useful Unix-domain + * socket */ + Socket *s = sk_new(sk_addr_dup(ux), 0, false, false, + false, false, nullplug); + err = sk_socket_error(s); + sk_close(s); + } + if (err) { + sk_addr_free(ux); + } else { + sk_addr_free(disp->addr); + disp->unixdomain = true; + disp->addr = ux; + /* Fill in the rest in a moment */ + } + } + + if (disp->unixdomain) { + if (!disp->addr) + disp->addr = platform_get_x11_unix_address(disp->unixsocketpath, + disp->displaynum); + if (disp->unixsocketpath) + disp->realhost = dupstr(disp->unixsocketpath); + else + disp->realhost = dupprintf("unix:%d", disp->displaynum); + disp->port = 0; + } + + /* + * Fetch the local authorisation details. + */ + disp->localauthproto = X11_NO_AUTH; + disp->localauthdata = NULL; + disp->localauthdatalen = 0; + platform_get_x11_auth(disp, conf); + + return disp; +} + +void x11_free_display(struct X11Display *disp) +{ + sfree(disp->hostname); + sfree(disp->unixsocketpath); + if (disp->localauthdata) + smemclr(disp->localauthdata, disp->localauthdatalen); + sfree(disp->localauthdata); + sk_addr_free(disp->addr); + sfree(disp); +} |