suEXEC: Add Suexec directive to disable suEXEC without renaming the

binary (Suexec Off), or force startup failure if suEXEC is required
but not supported (Suexec On).  Change SuexecUserGroup to fail
startup instead of just printing a warning if suEXEC is disabled.

Additionally, ap_unixd_config.suexec_disabled_reason has a message,
suitable for logging/messaging, explaining why the feature isn't
available.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1033519 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/CHANGES b/CHANGES
index 81d6db7ebeeb3b26afa06244f51640eb5cfd5c30..4d780b102b43051f0fa4f4608d66bf02ea1c6a38 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -6,6 +6,12 @@ Changes with Apache 2.3.9
      Fix a denial of service attack against mod_reqtimeout.
      [Stefan Fritsch]
 
+  *) suEXEC: Add Suexec directive to disable suEXEC without renaming the
+     binary (Suexec Off), or force startup failure if suEXEC is required
+     but not supported (Suexec On).  Change SuexecUserGroup to fail 
+     startup instead of just printing a warning if suEXEC is disabled.
+     [Jeff Trawick]
+
   *) core: Add Error directive for aborting startup or htaccess processing
      with a specified error message.  [Jeff Trawick]
 

diff --git a/docs/manual/mod/mod_suexec.xml b/docs/manual/mod/mod_suexec.xml
index 1bdbb4c2d0c647b01d6dfdb8fa3b52bfa26884e6..17f05a3267a171c9741189bd7c1367145c8ca7ca 100644 (file)
--- a/docs/manual/mod/mod_suexec.xml
+++ b/docs/manual/mod/mod_suexec.xml
@@ -62,8 +62,11 @@ later.</compatibility>
     SuexecUserGroup nobody nogroup
     </example>
 
+    <p>In Apache httpd 2.3.9 and later, startup will fail if this
+    directive is specified but the suEXEC feature is disabled.</p>
 </usage>
-
+<seealso><directive module="mod_unixd">Suexec</directive></seealso>
 </directivesynopsis>
+
 </modulesynopsis>
 

diff --git a/docs/manual/mod/mod_unixd.xml b/docs/manual/mod/mod_unixd.xml
index 257e3edc7175dad7afcfcf7a05e368ee05b9923b..9c8fe0636a368e9968d11b1193b7d4630ef99edd 100644 (file)
--- a/docs/manual/mod/mod_unixd.xml
+++ b/docs/manual/mod/mod_unixd.xml
@@ -26,6 +26,8 @@
 <description>Basic (required) security for Unix-family platforms.</description>
 <status>Base</status>
 
+<seealso><a href="../suexec.html">suEXEC support</a></seealso>
+
 <directivesynopsis>
 <name>Group</name>
 <description>Group under which the server will answer
@@ -139,4 +141,21 @@ requests</description>
 </usage>
 </directivesynopsis>
 
+<directivesynopsis>
+<name>Suexec</name>
+<description>Enable or disable the suEXEC feature</description>
+<syntax>Suexec On|Off</syntax>
+<default>On if suexec binary exists with proper owner and mode,
+Off otherwise</default>
+<contextlist><context>server config</context></contextlist>
+<compatibility>Available in Apache httpd 2.3.9 and later</compatibility>
+
+<usage>
+    <p>When On, startup will fail if the suexec binary doesn't exist
+    or has an invalid owner or file mode.</p>
+    <p>When Off, suEXEC will be disabled even if the suexec binary exists
+    and has a valid owner and file mode.</p>
+</usage>
+</directivesynopsis>
+
 </modulesynopsis>

diff --git a/include/ap_mmn.h b/include/ap_mmn.h
index 2922e41a58de36dd33f47b7acec746bba96445da..3c9250a850bcec360a45f1d7f9bcb212dca87b39 100644 (file)
--- a/include/ap_mmn.h
+++ b/include/ap_mmn.h
@@ -282,6 +282,7 @@
  *                         mod_ssl's parser. Clean up ap_expr's public
  *                         interface.
  * 20101106.1 (2.3.9-dev)  Add ap_pool_cleanup_set_null() generic cleanup
+ * 20101106.2 (2.3.9-dev)  Add suexec_disabled_reason field to ap_unixd_config
  */
 
 #define MODULE_MAGIC_COOKIE 0x41503234UL /* "AP24" */

diff --git a/modules/arch/unix/mod_unixd.c b/modules/arch/unix/mod_unixd.c
index 50395ee19c44f67358a34da9a42afda6792d4ae1..af30720662d90fba8a6f8868506690a5d2b56c67 100644 (file)
--- a/modules/arch/unix/mod_unixd.c
+++ b/modules/arch/unix/mod_unixd.c
@@ -260,6 +260,28 @@ unixd_set_chroot_dir(cmd_parms *cmd, void *dummy,
     return NULL;
 }
 
+static const char *
+unixd_set_suexec(cmd_parms *cmd, void *dummy, int arg)
+{
+    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+
+    if (err != NULL) {
+        return err;
+    }
+
+    if (!ap_unixd_config.suexec_enabled && arg) {
+        return apr_pstrcat(cmd->pool, "suEXEC isn't supported: ",
+                           ap_unixd_config.suexec_disabled_reason, NULL);
+    }
+
+    if (!arg) {
+        ap_unixd_config.suexec_disabled_reason = "Suexec directive is Off";
+    }
+
+    ap_unixd_config.suexec_enabled = arg;
+    return NULL;
+}
+
 static int 
 unixd_pre_config(apr_pool_t *pconf, apr_pool_t *plog,
                  apr_pool_t *ptemp)
@@ -278,7 +300,16 @@ unixd_pre_config(apr_pool_t *pconf, apr_pool_t *plog,
         if ((wrapper.protection & APR_USETID) && wrapper.user == 0
             && (access(SUEXEC_BIN, R_OK|X_OK) == 0)) {
             ap_unixd_config.suexec_enabled = 1;
+            ap_unixd_config.suexec_disabled_reason = "";
         }
+        else {
+            ap_unixd_config.suexec_disabled_reason =
+                "Invalid owner or file mode for " SUEXEC_BIN;
+        }
+    }
+    else {
+        ap_unixd_config.suexec_disabled_reason =
+            "Missing suexec binary " SUEXEC_BIN;
     }
 
     ap_sys_privileges_handlers(1);
@@ -354,6 +385,8 @@ static const command_rec unixd_cmds[] = {
                   "Effective group id for this server"),
     AP_INIT_TAKE1("ChrootDir", unixd_set_chroot_dir, NULL, RSRC_CONF,
                   "The directory to chroot(2) into"),
+    AP_INIT_FLAG("Suexec", unixd_set_suexec, NULL, RSRC_CONF,
+                 "Enable or disable suEXEC support"),
     {NULL}
 };
 

diff --git a/modules/generators/mod_suexec.c b/modules/generators/mod_suexec.c
index e548d71cdc726163440b1e27629b7df56cca6cc6..9a7d2cfe4f7237a2486a1df7229c5972ab9c4eef 100644 (file)
--- a/modules/generators/mod_suexec.c
+++ b/modules/generators/mod_suexec.c
@@ -64,16 +64,18 @@ static const char *set_suexec_ugid(cmd_parms *cmd, void *mconfig,
     if (err != NULL) {
         return err;
     }
-    if (ap_unixd_config.suexec_enabled) {
-        cfg->ugid.uid = ap_uname2id(uid);
-        cfg->ugid.gid = ap_gname2id(gid);
-        cfg->ugid.userdir = 0;
-        cfg->active = 1;
-    }
-    else {
-        fprintf(stderr,
-                "Warning: SuexecUserGroup directive requires SUEXEC wrapper.\n");
+
+    if (!ap_unixd_config.suexec_enabled) {
+        return apr_pstrcat(cmd->pool, "SuexecUserGroup configured, but "
+                           "suEXEC is disabled: ",
+                           ap_unixd_config.suexec_disabled_reason, NULL);
     }
+
+    cfg->ugid.uid = ap_uname2id(uid);
+    cfg->ugid.gid = ap_gname2id(gid);
+    cfg->ugid.userdir = 0;
+    cfg->active = 1;
+
     return NULL;
 }
 

diff --git a/os/unix/unixd.h b/os/unix/unixd.h
index c9d6ea96a294dd268d7497444ae516fd9f01a0bf..6b8a79ae32d950cf70a6c77fb8d16512453ba670 100644 (file)
--- a/os/unix/unixd.h
+++ b/os/unix/unixd.h
@@ -77,6 +77,7 @@ typedef struct {
     gid_t group_id;
     int suexec_enabled;
     const char *chroot_dir;
+    const char *suexec_disabled_reason; /* suitable msg if !suexec_enabled */
 } unixd_config_rec;
 AP_DECLARE_DATA extern unixd_config_rec ap_unixd_config;