Improve X11 shadow authentication reason failure log

(cherry picked from commit e66ee477c00b91cddc228adaf1577be602e4f725)

diff --git a/server/shadow/X11/x11_shadow.c b/server/shadow/X11/x11_shadow.c
index 9dfa12a..98cf44d 100644 (file)
--- a/server/shadow/X11/x11_shadow.c
+++ b/server/shadow/X11/x11_shadow.c
@@ -128,90 +128,69 @@ out_fail:
        return pam_status;
 }
 
-static int x11_shadow_pam_get_service_name(SHADOW_PAM_AUTH_INFO* info)
+static BOOL x11_shadow_pam_get_service_name(SHADOW_PAM_AUTH_INFO* info)
 {
-       if (PathFileExistsA("/etc/pam.d/lightdm"))
-       {
-               info->service_name = _strdup("lightdm");
-       }
-       else if (PathFileExistsA("/etc/pam.d/gdm"))
-       {
-               info->service_name = _strdup("gdm");
-       }
-       else if (PathFileExistsA("/etc/pam.d/xdm"))
-       {
-               info->service_name = _strdup("xdm");
-       }
-       else if (PathFileExistsA("/etc/pam.d/login"))
-       {
-               info->service_name = _strdup("login");
-       }
-       else if (PathFileExistsA("/etc/pam.d/sshd"))
-       {
-               info->service_name = _strdup("sshd");
-       }
-       else
+       size_t x;
+       const char* base = "/etc/pam.d";
+       const char* hints[] = { "lightdm", "gdm", "xdm", "login", "sshd" };
+
+       for (x = 0; x < ARRAYSIZE(hints); x++)
        {
-               return -1;
-       }
+               char path[MAX_PATH];
+               const char* hint = hints[x];
 
-       if (!info->service_name)
-               return -1;
+               _snprintf(path, sizeof(path), "%s/%s", base, hint);
+               if (PathFileExistsA(path))
+               {
 
-       return 1;
+                       info->service_name = _strdup(hint);
+                       return info->service_name != NULL;
+               }
+       }
+       WLog_WARN(TAG, "Could not determine PAM service name");
+       return FALSE;
 }
 
 static int x11_shadow_pam_authenticate(rdpShadowSubsystem* subsystem, rdpShadowClient* client,
                                        const char* user, const char* domain, const char* password)
 {
        int pam_status;
-       SHADOW_PAM_AUTH_INFO* info;
+       SHADOW_PAM_AUTH_INFO info = { 0 };
        WINPR_UNUSED(subsystem);
        WINPR_UNUSED(client);
-       info = calloc(1, sizeof(SHADOW_PAM_AUTH_INFO));
-
-       if (!info)
-               return PAM_CONV_ERR;
 
-       if (x11_shadow_pam_get_service_name(info) < 0)
-       {
-               free(info);
+       if (!x11_shadow_pam_get_service_name(&info))
                return -1;
-       }
 
-       info->appdata.user = user;
-       info->appdata.domain = domain;
-       info->appdata.password = password;
-       info->pamc.conv = &x11_shadow_pam_conv;
-       info->pamc.appdata_ptr = &(info->appdata);
-       pam_status = pam_start(info->service_name, 0, &(info->pamc), &(info->handle));
+       info.appdata.user = user;
+       info.appdata.domain = domain;
+       info.appdata.password = password;
+       info.pamc.conv = &x11_shadow_pam_conv;
+       info.pamc.appdata_ptr = &(info->appdata);
+       pam_status = pam_start(info->service_name, 0, &info.pamc, &info.handle);
 
        if (pam_status != PAM_SUCCESS)
        {
-               WLog_ERR(TAG, "pam_start failure: %s", pam_strerror(info->handle, pam_status));
-               free(info);
+               WLog_ERR(TAG, "pam_start failure: %s", pam_strerror(info.handle, pam_status));
                return -1;
        }
 
-       pam_status = pam_authenticate(info->handle, 0);
+       pam_status = pam_authenticate(info.handle, 0);
 
        if (pam_status != PAM_SUCCESS)
        {
-               WLog_ERR(TAG, "pam_authenticate failure: %s", pam_strerror(info->handle, pam_status));
-               free(info);
+               WLog_ERR(TAG, "pam_authenticate failure: %s", pam_strerror(info.handle, pam_status));
                return -1;
        }
 
-       pam_status = pam_acct_mgmt(info->handle, 0);
+       pam_status = pam_acct_mgmt(info.handle, 0);
 
        if (pam_status != PAM_SUCCESS)
        {
-               WLog_ERR(TAG, "pam_acct_mgmt failure: %s", pam_strerror(info->handle, pam_status));
-               free(info);
+               WLog_ERR(TAG, "pam_acct_mgmt failure: %s", pam_strerror(info.handle, pam_status));
                return -1;
        }
 
-       free(info);
        return 1;
 }