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#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>
#include <security/pam_modules.h>
#include <security/pam_modutil.h>
#include <security/pam_appl.h>
#define PAM_TYPE_DOMAIN 1234
/* Either grab a value or prompt for it */
static char *
get_item (pam_handle_t * pamh, int type)
{
/* Check to see if we just have the value. If we do, great
let's dup it some we're consitently allocating memory */
if (type != PAM_TYPE_DOMAIN) {
char * value;
if (pam_get_item(pamh, type, (const void **)&value) == PAM_SUCCESS) {
return strdup(value);
}
}
/* Now we need to prompt */
/* Build up the message we're prompting for */
struct pam_message message[1];
message[0].msg_style = PAM_PROMPT_ECHO_ON;
switch (type) {
case PAM_USER:
message[0].msg = "login:";
break;
case PAM_RUSER:
message[0].msg = "remote login:";
break;
case PAM_RHOST:
message[0].msg = "remote host:";
break;
case PAM_AUTHTOK:
message[0].msg = "password:";
message[0].msg_style = PAM_PROMPT_ECHO_OFF;
break;
case PAM_TYPE_DOMAIN:
message[0].msg = "domain:";
break;
default:
return NULL;
}
struct pam_conv * conv;
if (pam_get_item(pamh, PAM_CONV, (const void **)&conv) != PAM_SUCCESS) {
return NULL;
}
struct pam_response * responses = NULL;
if (conv->conv(1, (const struct pam_message **)&message, &responses, conv->appdata_ptr) != PAM_SUCCESS) {
return NULL;
}
char * retval = responses->resp;
free(responses);
return retval;
}
#define GET_ITEM(val, type) \
if ((val = get_item(pamh, type)) == NULL) { \
retval = PAM_AUTH_ERR; \
goto done; \
}
/* TODO: Make this a build thing */
#define XFREERDP "/usr/bin/xfreerdp"
/* Authenticate. We need to make sure we have a user account, that
there are remote accounts and then verify them with FreeRDP */
PAM_EXTERN int
pam_sm_authenticate (pam_handle_t *pamh, int flags, int argc, const char **argv)
{
char * username = NULL;
char * password = NULL;
char * ruser = NULL;
char * rhost = NULL;
char * rdomain = NULL;
int retval = PAM_IGNORE;
/* Get all the values, or prompt for them, or return with
an auth error */
GET_ITEM(username, PAM_USER);
GET_ITEM(ruser, PAM_RUSER);
GET_ITEM(rhost, PAM_RHOST);
GET_ITEM(rdomain, PAM_TYPE_DOMAIN);
GET_ITEM(password, PAM_AUTHTOK);
/* At this point we should have the values, let's check the auth */
pid_t pid;
switch (pid = fork()) {
case 0: { /* child */
char * args[13];
args[0] = XFREERDP;
args[1] = "--plugin";
args[2] = "rdpsnd.so";
args[3] = "--no-nla";
args[4] = "-f";
args[5] = "--ignore-certificate"; /* TODO: Change when we set the home directory properly */
/* TODO: Use stdin */
args[6] = "-u";
args[7] = ruser;
args[8] = "-p";
args[9] = password;
args[10] = "-d";
args[11] = rdomain;
args[12] = NULL;
/* TODO: Drop privs */
/* TODO: Home directory environment to user's home */
execvp(args[0], args);
_exit(EXIT_FAILURE);
break;
}
case -1: { /* fork'n error! */
retval = PAM_SYSTEM_ERR;
break;
}
default: {
int forkret = 0;
if (waitpid(pid, &forkret, 0) < 0) {
retval = PAM_SYSTEM_ERR;
} else if (forkret == 0) {
retval = PAM_SUCCESS;
} else {
retval = PAM_AUTH_ERR;
}
}
}
/* Free Memory and return our status */
done:
if (username != NULL) { free(username); }
if (password != NULL) { free(password); }
if (ruser != NULL) { free(ruser); }
if (rhost != NULL) { free(rhost); }
if (rdomain != NULL) { free(rdomain); }
return retval;
}
/* Open Session. Here we need to fork a little process so that we can
give the credentials to the session itself so that it can startup the
xfreerdp viewer for the login */
PAM_EXTERN int
pam_sm_open_session (pam_handle_t *pamh, int flags, int argc, const char **argv)
{
return PAM_IGNORE;
}
/* Close Session. Make sure our little guy has died so he doesn't become
a zombie and eat things. */
PAM_EXTERN int
pam_sm_close_session (pam_handle_t *pamh, int flags, int argc, const char **argv)
{
return PAM_IGNORE;
}
#ifdef PAM_STATIC
struct pam_module _pam_temp_account_modstruct = {
"pam-freerdp",
pam_sm_authenticate,
NULL,
NULL,
pam_sm_open_session,
pam_sm_close_session,
NULL,
};
#endif
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