wayvnc/src/pam_auth.c

84 lines
2.4 KiB
C

/*
* Copyright (c) 2020 Nicholas Sica
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
#include "pam_auth.h"
#include <stdlib.h>
#include <string.h>
#include <security/pam_appl.h>
#include <neatvnc.h>
struct credentials {
const char* user;
const char* password;
};
static int pam_return_pwd(int num_msg, const struct pam_message** msgm,
struct pam_response** response, void* appdata_ptr)
{
struct credentials* cred = appdata_ptr;
struct pam_response* resp = calloc(sizeof(*response), num_msg);
for (int i = 0; i < num_msg; i++) {
resp[i].resp_retcode = PAM_SUCCESS;
switch(msgm[i]->msg_style) {
case PAM_PROMPT_ECHO_OFF:
resp[i].resp = strdup(cred->password);
break;
default:
goto error;
}
}
*response = resp;
return PAM_SUCCESS;
error:
for (int i = 0; i < num_msg; i++) {
free(resp[i].resp);
}
free(resp);
return PAM_CONV_ERR;
}
bool pam_auth(const char* username, const char* password)
{
struct credentials cred = { username, password };
struct pam_conv conv = { &pam_return_pwd, &cred };
const char* service = "wayvnc";
pam_handle_t* pamh;
int result = pam_start(service, username, &conv, &pamh);
if (result != PAM_SUCCESS) {
nvnc_log(NVNC_LOG_ERROR, "ERROR: PAM start failed: %s", pam_strerror(pamh, result));
return false;
}
result = pam_authenticate(pamh, PAM_SILENT|PAM_DISALLOW_NULL_AUTHTOK);
if (result != PAM_SUCCESS) {
nvnc_log(NVNC_LOG_ERROR, "PAM authenticate failed: %s", pam_strerror(pamh, result));
goto error;
}
result = pam_acct_mgmt(pamh, 0);
if (result != PAM_SUCCESS) {
nvnc_log(NVNC_LOG_ERROR, "PAM account management failed: %s", pam_strerror(pamh, result));
goto error;
}
error:
pam_end(pamh, result);
return result == PAM_SUCCESS;
}