From 8f8cc5f4c2d6882f169b19d670b922844f66150d Mon Sep 17 00:00:00 2001
From: Andy Fiddaman <andy@omniosce.org>
Date: Tue, 3 Mar 2020 10:51:47 +0000
Subject: [PATCH] Merge pull request #1434 from citrus-it/illumos-auth-socket

MDEV-21476: auth_socket: add support for illumos with getpeerucred()
---
 plugin/auth_socket/CMakeLists.txt | 27 +++++++++++++++++++++++++++
 plugin/auth_socket/auth_socket.c  | 19 ++++++++++++++++++-
 2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/plugin/auth_socket/CMakeLists.txt b/plugin/auth_socket/CMakeLists.txt
index 5a59520a3e418..6f3d571ea43db 100644
--- a/plugin/auth_socket/CMakeLists.txt
+++ b/plugin/auth_socket/CMakeLists.txt
@@ -57,12 +57,39 @@ IF (HAVE_XUCRED)
   SET(ok 1)
 ELSE()
 
+# illumos, is that you?
+CHECK_CXX_SOURCE_COMPILES(
+"#include <ucred.h>
+int main() {
+  ucred_t *cred = NULL;
+  getpeerucred(0, &cred);
+  }" HAVE_GETPEERUCRED)
+
+# Depending on the flags set in the compilation environment, illumos will have
+# either the POSIX.1c draft 6 or POSIX.1c final implementation of getpwuid_r()
+# Check that defining _POSIX_PTHREAD_SEMANTICS provides the final standard
+# version.
+
+CHECK_CXX_SOURCE_COMPILES(
+"#define _POSIX_PTHREAD_SEMANTICS
+#include <pwd.h>
+int main() {
+  getpwuid_r(0, NULL, NULL, 0, NULL);
+  }" HAVE_GETPWUID_POSIX_FINAL)
+
+IF (HAVE_GETPEERUCRED AND HAVE_GETPWUID_POSIX_FINAL)
+  ADD_DEFINITIONS(-DHAVE_GETPEERUCRED)
+  ADD_DEFINITIONS(-D_POSIX_PTHREAD_SEMANTICS)
+  SET(ok 1)
+ELSE()
+
 # Who else? Anyone?
 # C'mon, show your creativity, be different! ifdef's are fun, aren't they?
 
 ENDIF()
 ENDIF()
 ENDIF()
+ENDIF()
 
 IF(ok)
   MYSQL_ADD_PLUGIN(auth_socket auth_socket.c DEFAULT)
diff --git a/plugin/auth_socket/auth_socket.c b/plugin/auth_socket/auth_socket.c
index 46eae517cb808..b10679a5cc2ce 100644
--- a/plugin/auth_socket/auth_socket.c
+++ b/plugin/auth_socket/auth_socket.c
@@ -47,6 +47,9 @@
 #define uid cr_uid
 #define ucred xucred
 
+#elif defined HAVE_GETPEERUCRED
+#include <ucred.h>
+
 #else
 #error impossible
 #endif
@@ -64,10 +67,15 @@ static int socket_auth(MYSQL_PLUGIN_VIO *vio, MYSQL_SERVER_AUTH_INFO *info)
 {
   unsigned char *pkt;
   MYSQL_PLUGIN_VIO_INFO vio_info;
+#ifdef HAVE_GETPEERUCRED
+  ucred_t *cred = NULL;
+#else
   struct ucred cred;
   socklen_t cred_len= sizeof(cred);
+#endif
   struct passwd pwd_buf, *pwd;
   char buf[1024];
+  uid_t u;
 
   /* no user name yet ? read the client handshake packet with the user name */
   if (info->user_name == 0)
@@ -83,14 +91,23 @@ static int socket_auth(MYSQL_PLUGIN_VIO *vio, MYSQL_SERVER_AUTH_INFO *info)
     return CR_ERROR;
 
   /* get the UID of the client process */
+#ifdef HAVE_GETPEERUCRED
+  if (getpeerucred(vio_info.socket, &cred) != 0)
+    return CR_ERROR;
+  u = ucred_geteuid(cred);
+  ucred_free(cred);
+#else
   if (getsockopt(vio_info.socket, level, SO_PEERCRED, &cred, &cred_len))
     return CR_ERROR;
 
   if (cred_len != sizeof(cred))
     return CR_ERROR;
 
+  u = cred.uid;
+#endif
+
   /* and find the username for this uid */
-  getpwuid_r(cred.uid, &pwd_buf, buf, sizeof(buf), &pwd);
+  getpwuid_r(u, &pwd_buf, buf, sizeof(buf), &pwd);
   if (pwd == NULL)
     return CR_ERROR;