core: deprecate and replace ap_get_basic_auth_pw

  *) core: Deprecate ap_get_basic_auth_pw() and add
    ap_get_basic_auth_components().

Submitted By: Emmanuel Dreyfus <manu netbsd.org>, Jacob Champion, Eric Covener
CVEID: CVE-2017-3167

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1796348 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/CHANGES b/CHANGES
index 4bc781682ff8dce9367c986db2fb0e3594c9a835..9d8833f4f46c9edd78ae6e1be266682c2009ae03 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,10 @@
                                                          -*- coding: utf-8 -*-
 Changes with Apache 2.5.0
 
+  *) core: Deprecate ap_get_basic_auth_pw() and add 
+     ap_get_basic_auth_components(). 
+     [Emmanuel Dreyfus <manu netbsd.org>, Jacob Champion, Eric Covener]
+
   *) mod_ssl: Consistently pass the expected bio_filter_in_ctx_t
      to ssl_io_filter_error(). [Yann Ylavic]
 

diff --git a/include/ap_mmn.h b/include/ap_mmn.h
index 0967996409d1c3587834e912e984683bf2f56b17..ca2484cf127df2ed1119229903b39c07783792c6 100644 (file)
--- a/include/ap_mmn.h
+++ b/include/ap_mmn.h
@@ -552,6 +552,8 @@
  * 20161018.2 (2.5.0-dev)  add ap_set_conn_count()
  * 20161018.3 (2.5.0-dev)  add ap_exists_directive()
  * 20161018.4 (2.5.0-dev)  Add taint to request_rec and ap_request_tainted()
+ * 20161018.5 (2.5.0-dev)  Add ap_get_basic_auth_components() and deprecate
+ *                         ap_get_basic_auth_pw()
  */
 
 #define MODULE_MAGIC_COOKIE 0x41503235UL /* "AP25" */
@@ -559,7 +561,7 @@
 #ifndef MODULE_MAGIC_NUMBER_MAJOR
 #define MODULE_MAGIC_NUMBER_MAJOR 20161018
 #endif
-#define MODULE_MAGIC_NUMBER_MINOR 4                 /* 0...n */
+#define MODULE_MAGIC_NUMBER_MINOR 5                 /* 0...n */
 
 /**
  * Determine if the server's current MODULE_MAGIC_NUMBER is at least a

diff --git a/include/http_protocol.h b/include/http_protocol.h
index 63c3b0cc651a2d8d55eea671327f34f2ea3d4e24..c5a6a60e3ea7add61d48d4447dc362dbc46fcb7e 100644 (file)
--- a/include/http_protocol.h
+++ b/include/http_protocol.h
@@ -576,7 +576,11 @@ AP_DECLARE(void) ap_note_digest_auth_failure(request_rec *r);
 AP_DECLARE_HOOK(int, note_auth_failure, (request_rec *r, const char *auth_type))
 
 /**
- * Get the password from the request headers
+ * Get the password from the request headers. This function has multiple side
+ * effects due to its prior use in the old authentication framework.
+ * ap_get_basic_auth_components() should be preferred.
+ *
+ * @deprecated @see ap_get_basic_auth_components
  * @param r The current request
  * @param pw The password as set in the headers
  * @return 0 (OK) if it set the 'pw' argument (and assured
@@ -589,6 +593,25 @@ AP_DECLARE_HOOK(int, note_auth_failure, (request_rec *r, const char *auth_type))
  */
 AP_DECLARE(int) ap_get_basic_auth_pw(request_rec *r, const char **pw);
 
+#define AP_GET_BASIC_AUTH_PW_NOTE "AP_GET_BASIC_AUTH_PW_NOTE"
+
+/**
+ * Get the username and/or password from the request's Basic authentication
+ * headers. Unlike ap_get_basic_auth_pw(), calling this function has no side
+ * effects on the passed request_rec.
+ *
+ * @param r The current request
+ * @param username If not NULL, set to the username sent by the client
+ * @param password If not NULL, set to the password sent by the client
+ * @return APR_SUCCESS if the credentials were successfully parsed and returned;
+ *         APR_EINVAL if there was no authentication header sent or if the
+ *         client was not using the Basic authentication scheme. username and
+ *         password are unchanged on failure.
+ */
+AP_DECLARE(apr_status_t) ap_get_basic_auth_components(const request_rec *r,
+                                                      const char **username,
+                                                      const char **password);
+
 /**
  * parse_uri: break apart the uri
  * @warning Side Effects:

diff --git a/server/protocol.c b/server/protocol.c
index 88e855bbd8403a7515e5c3467f3ba6bc29e4eb65..e659135c211b4a5c5f78ff7e1a38517eed925edd 100644 (file)
--- a/server/protocol.c
+++ b/server/protocol.c
@@ -1627,6 +1627,7 @@ AP_DECLARE(int) ap_get_basic_auth_pw(request_rec *r, const char **pw)
 
     t = ap_pbase64decode(r->pool, auth_line);
     r->user = ap_getword_nulls (r->pool, &t, ':');
+    apr_table_setn(r->notes, AP_GET_BASIC_AUTH_PW_NOTE, "1");
     r->ap_auth_type = "Basic";
 
     *pw = t;
@@ -1634,6 +1635,53 @@ AP_DECLARE(int) ap_get_basic_auth_pw(request_rec *r, const char **pw)
     return OK;
 }
 
+AP_DECLARE(apr_status_t) ap_get_basic_auth_components(const request_rec *r,
+                                                      const char **username,
+                                                      const char **password)
+{
+    const char *auth_header;
+    const char *credentials;
+    const char *decoded;
+    const char *user;
+
+    auth_header = (PROXYREQ_PROXY == r->proxyreq) ? "Proxy-Authorization"
+                                                  : "Authorization";
+    credentials = apr_table_get(r->headers_in, auth_header);
+
+    if (!credentials) {
+        /* No auth header. */
+        return APR_EINVAL;
+    }
+
+    if (ap_cstr_casecmp(ap_getword(r->pool, &credentials, ' '), "Basic")) {
+        /* These aren't Basic credentials. */
+        return APR_EINVAL;
+    }
+
+    while (*credentials == ' ' || *credentials == '\t') {
+        credentials++;
+    }
+
+    /* XXX Our base64 decoding functions don't actually error out if the string
+     * we give it isn't base64; they'll just silently stop and hand us whatever
+     * they've parsed up to that point.
+     *
+     * Since this function is supposed to be a drop-in replacement for the
+     * deprecated ap_get_basic_auth_pw(), don't fix this for 2.4.x.
+     */
+    decoded = ap_pbase64decode(r->pool, credentials);
+    user = ap_getword_nulls(r->pool, &decoded, ':');
+
+    if (username) {
+        *username = user;
+    }
+    if (password) {
+        *password = decoded;
+    }
+
+    return APR_SUCCESS;
+}
+
 struct content_length_ctx {
     int data_sent;  /* true if the C-L filter has already sent at
                      * least one bucket on to the next output filter

diff --git a/server/request.c b/server/request.c
index 016504d1cdcb026ffecfcf5ad296dfcbdf36bbda..55c32b276b092d7a956fd2547f1b58ed1ab14e9b 100644 (file)
--- a/server/request.c
+++ b/server/request.c
@@ -124,6 +124,8 @@ static int decl_die(int status, const char *phase, request_rec *r)
 AP_DECLARE(int) ap_some_authn_required(request_rec *r)
 {
     int access_status;
+    char *olduser = r->user;
+    int rv = FALSE;
 
     switch (ap_satisfies(r)) {
     case SATISFY_ALL:
@@ -134,7 +136,7 @@ AP_DECLARE(int) ap_some_authn_required(request_rec *r)
 
         access_status = ap_run_access_checker_ex(r);
         if (access_status == DECLINED) {
-            return TRUE;
+            rv = TRUE;
         }
 
         break;
@@ -145,13 +147,14 @@ AP_DECLARE(int) ap_some_authn_required(request_rec *r)
 
         access_status = ap_run_access_checker_ex(r);
         if (access_status == DECLINED) {
-            return TRUE;
+            rv = TRUE;
         }
 
         break;
     }
 
-    return FALSE;
+    r->user = olduser;
+    return rv;
 }
 
 /* This is the master logic for processing requests.  Do NOT duplicate
@@ -263,6 +266,14 @@ AP_DECLARE(int) ap_process_request_internal(request_rec *r)
         r->ap_auth_type = r->main->ap_auth_type;
     }
     else {
+        /* A module using a confusing API (ap_get_basic_auth_pw) caused
+        ** r->user to be filled out prior to check_authn hook. We treat
+        ** it is inadvertent.
+        */
+        if (r->user && apr_table_get(r->notes, AP_GET_BASIC_AUTH_PW_NOTE)) { 
+            r->user = NULL;
+        }
+
         switch (ap_satisfies(r)) {
         case SATISFY_ALL:
         case SATISFY_NOSPEC: