reload HTTP proxy credentials when moving to the next connection profile

The HTTP proxy credentials are stored in a static variable that is possibly initialized before each connection attempt.

However, the variable is never "released" therefore get_user_pass() refuses to overwrite its content and leaves it as it is. Consequently, if the user config contains multiple connection profiles with different http-proxy, each having its own credentials, only the first user/pass couple is loaded and the others are all ignored. This leads to connection failures because the proper credentials are not associated with the right proxy server.

The root of the misbehaviour seems to be located in the fact that, despite the argument force passed to get_user_pass_http() being true, no action is taken to release the static object containing the credentials.

Fix the misbehaviour by releasing the http-proxy credential object when the reload is "forced".

Trac: #836

Signed-off-by Antonio Quartulli <[email protected]...>

---

v2:
- rebased on current master

 src/openvpn/proxy.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

src/openvpn/proxy.c +0 -0

index fdc73b4a..cfc1d11c 100644
@@ -255,7 +255,16 @@ username_password_as_base64(const struct http_proxy_info *p,
 static void
 get_user_pass_http(struct http_proxy_info *p, const bool force)

Hi,

Feature-ACK, but one implementation concern:

Quoted 44 lines · Antonio Quartulli

The HTTP proxy credentials are stored in a static variable that is possibly initialized before each connection attempt.

However, the variable is never "released" therefore get_user_pass() refuses to overwrite its content and leaves it as it is. Consequently, if the user config contains multiple connection profiles with different http-proxy, each having its own credentials, only the first user/pass couple is loaded and the others are all ignored. This leads to connection failures because the proper credentials are not associated with the right proxy server.

The root of the misbehaviour seems to be located in the fact that, despite the argument force passed to get_user_pass_http() being true, no action is taken to release the static object containing the credentials.

Fix the misbehaviour by releasing the http-proxy credential object when the reload is "forced".

Trac: #836

Signed-off-by Antonio Quartulli <[email protected]...>

---

v2:
- rebased on current master

 src/openvpn/proxy.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

src/openvpn/proxy.c +6 -1

index fdc73b4a..cfc1d11c 100644
@@ -255,7 +255,16 @@ username_password_as_base64(const struct http_proxy_info *p,
 static void
 get_user_pass_http(struct http_proxy_info *p, const bool force)
 {
-    if (!static_proxy_user_pass.defined || force)
+    /*
+     * in case of forced (re)load, make sure the static storage is set as
+     * undefined, otherwise get_user_pass() won't try to load any credential
+     */
+    if (force)
+    {

src/openvpn/proxy.c username_password_as_base64(const struct http_proxy_info *p, · line 265

Quoted 2 lines

src/openvpn/proxy.c +2 -0

+        static_proxy_user_pass.defined = false;
+    }

I'm wondering, shouldn't we clear the username/password in the struct if we set defined=false as a hardening measure? And shouldn't we then just replace this if(force) block with a call to purge_user_pass(up, force)? Or should we be careful to not clear the other members of static_proxy_user_pass?

-Steffan

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The HTTP proxy credentials are stored in a static variable that is possibly initialized before each connection attempt.

However, the variable is never "released" therefore get_user_pass() refuses to overwrite its content and leaves it as it is. Consequently, if the user config contains multiple connection profiles with different http-proxy, each having its own credentials, only the first user/pass couple is loaded and the others are all ignored. This leads to connection failures because the proper credentials are not associated with the right proxy server.

The root of the misbehaviour seems to be located in the fact that, despite the argument force passed to get_user_pass_http() being true, no action is taken to release the static object containing the credentials.

Fix the misbehaviour by releasing the http-proxy credential object when the reload is "forced".

Trac: #836

Signed-off-by Antonio Quartulli <[email protected]...>

---

v4:
- move clear_user_pass_http() above its invocation to prevent compile error

v3:
- call clear_user_pass_http() directly to clear user/pass object

v2:
- rebased on current master

 src/openvpn/proxy.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

src/openvpn/proxy.c +16 -1

index fdc73b4a..de0188a9 100644
@@ -252,10 +252,25 @@ username_password_as_base64(const struct http_proxy_info *p,
     return (const char *)make_base64_string((const uint8_t *)BSTR(&out), gc);
 }
 
+static void
+clear_user_pass_http(void)
+{
+    purge_user_pass(&static_proxy_user_pass, true);
+}
+
 static void
 get_user_pass_http(struct http_proxy_info *p, const bool force)
 {
-    if (!static_proxy_user_pass.defined || force)
+    /*
+     * in case of forced (re)load, make sure the static storage is set as
+     * undefined, otherwise get_user_pass() won't try to load any credential
+     */
+    if (force)
+    {
+        clear_user_pass_http();
+    }
+
+    if (!static_proxy_user_pass.defined)
     {
         unsigned int flags = GET_USER_PASS_MANAGEMENT;
         if (p->queried_creds)

@@ -274,11 +289,6 @@ get_user_pass_http(struct http_proxy_info *p, const bool force)
         p->up = static_proxy_user_pass;