CC: curl: fix CVE-2016-0755

This fixes the following security problem:
CVE-2016-0755: NTLM credentials not-checked for proxy connection re-use
http://curl.haxx.se/docs/adv_20160127B.html

backport of r48614.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>


git-svn-id: svn://svn.openwrt.org/openwrt/branches/chaos_calmer@48872 3c298f89-4303-0410-b956-a3cf2f4a3e73

package/network/utils/curl/patches/018-CVE-2016-0755.patch

@@ -0,0 +1,126 @@
+From d41dcba4e9b69d6b761e3460cc6ae7e8fd8f621f Mon Sep 17 00:00:00 2001
+From: Isaac Boukris <iboukris@gmail.com>
+Date: Wed, 13 Jan 2016 11:05:51 +0200
+Subject: [PATCH] NTLM: Fix ConnectionExists to compare Proxy credentials
+
+Proxy NTLM authentication should compare credentials when
+re-using a connection similar to host authentication, as it
+authenticate the connection.
+
+Example:
+curl -v -x http://proxy:port http://host/ -U good_user:good_pwd
+  --proxy-ntlm --next -x http://proxy:port http://host/
+    [-U fake_user:fake_pwd --proxy-ntlm]
+
+CVE-2016-0755
+
+Bug: http://curl.haxx.se/docs/adv_20160127A.html
+---
+ lib/url.c | 62 ++++++++++++++++++++++++++++++++++++++++----------------------
+ 1 file changed, 40 insertions(+), 22 deletions(-)
+
+--- a/lib/url.c
++++ b/lib/url.c
+@@ -3044,11 +3044,16 @@ ConnectionExists(struct SessionHandle *d
+   struct connectdata *check;
+   struct connectdata *chosen = 0;
+   bool canPipeline = IsPipeliningPossible(data, needle);
+-  bool wantNTLMhttp = ((data->state.authhost.want & CURLAUTH_NTLM) ||
+-                       (data->state.authhost.want & CURLAUTH_NTLM_WB)) &&
+-    (needle->handler->protocol & PROTO_FAMILY_HTTP) ? TRUE : FALSE;
+   struct connectbundle *bundle;
+
++  bool wantNTLMhttp = ((data->state.authhost.want &
++                      (CURLAUTH_NTLM | CURLAUTH_NTLM_WB)) &&
++                      (needle->handler->protocol & PROTO_FAMILY_HTTP));
++  bool wantProxyNTLMhttp = (needle->bits.proxy_user_passwd &&
++                           ((data->state.authproxy.want &
++                           (CURLAUTH_NTLM | CURLAUTH_NTLM_WB)) &&
++                           (needle->handler->protocol & PROTO_FAMILY_HTTP)));
++
+   *force_reuse = FALSE;
+
+   /* We can't pipe if the site is blacklisted */
+@@ -3077,9 +3082,6 @@ ConnectionExists(struct SessionHandle *d
+     curr = bundle->conn_list->head;
+     while(curr) {
+       bool match = FALSE;
+-#if defined(USE_NTLM)
+-      bool credentialsMatch = FALSE;
+-#endif
+       size_t pipeLen;
+
+       /*
+@@ -3185,21 +3187,14 @@ ConnectionExists(struct SessionHandle *d
+       }
+
+       if((!(needle->handler->flags & PROTOPT_CREDSPERREQUEST)) ||
+-#if defined(USE_NTLM)
+-         (wantNTLMhttp || check->ntlm.state != NTLMSTATE_NONE)) {
+-#else
+          wantNTLMhttp) {
+-#endif
+-        /* This protocol requires credentials per connection or is HTTP+NTLM,
++        /* This protocol requires credentials per connection,
+            so verify that we're using the same name and password as well */
+         if(!strequal(needle->user, check->user) ||
+            !strequal(needle->passwd, check->passwd)) {
+           /* one of them was different */
+           continue;
+         }
+-#if defined(USE_NTLM)
+-        credentialsMatch = TRUE;
+-#endif
+       }
+
+       if(!needle->bits.httpproxy || needle->handler->flags&PROTOPT_SSL ||
+@@ -3258,20 +3253,43 @@ ConnectionExists(struct SessionHandle *d
+            possible. (Especially we must not reuse the same connection if
+            partway through a handshake!) */
+         if(wantNTLMhttp) {
+-          if(credentialsMatch && check->ntlm.state != NTLMSTATE_NONE) {
+-            chosen = check;
++          if(!strequal(needle->user, check->user) ||
++             !strequal(needle->passwd, check->passwd))
++            continue;
++        }
++        else if(check->ntlm.state != NTLMSTATE_NONE) {
++          /* Connection is using NTLM auth but we don't want NTLM */
++          continue;
++        }
+
++        /* Same for Proxy NTLM authentication */
++        if(wantProxyNTLMhttp) {
++          if(!strequal(needle->proxyuser, check->proxyuser) ||
++             !strequal(needle->proxypasswd, check->proxypasswd))
++            continue;
++        }
++        else if(check->proxyntlm.state != NTLMSTATE_NONE) {
++          /* Proxy connection is using NTLM auth but we don't want NTLM */
++          continue;
++        }
++
++        if(wantNTLMhttp || wantProxyNTLMhttp) {
++          /* Credentials are already checked, we can use this connection */
++          chosen = check;
++
++          if((wantNTLMhttp &&
++             (check->ntlm.state != NTLMSTATE_NONE)) ||
++              (wantProxyNTLMhttp &&
++               (check->proxyntlm.state != NTLMSTATE_NONE))) {
+             /* We must use this connection, no other */
+             *force_reuse = TRUE;
+             break;
+           }
+-          else if(credentialsMatch)
+-            /* this is a backup choice */
+-            chosen = check;
++
++          /* Continue look up for a better connection */
+           continue;
+         }
+ #endif
+-
+         if(canPipeline) {
+           /* We can pipeline if we want to. Let's continue looking for
+              the optimal connection to use, i.e the shortest pipe that is not