Backport bnotes needed by RHEL-46040 fix

bnotes are actually not bnotes, but it has been slightly modified for
2.4.37 purposes to use r->notes, since bnotes are not available in this
httpd version and we didn't want to break ABI.

Related: RHEL-46040 - httpd:2.4/httpd: Security issues via backend
applications whose response headers are malicious or exploitable (CVE-2024-38476)

httpd-2.4.37-CVE-2024-38476.patch

@@ -1,3 +1,8 @@
+
+-- backported bnotes needed by this CVE fix from https://svn.apache.org/viewvc?view=revision&revision=1887384
+-- modified it a little bit so it actually doesn't store bnotes into req structure to not brake compatibility
+-- but it stores AP_REQUEST_TRUSTED_CT info into r->notes
+
 diff --git a/include/http_protocol.h b/include/http_protocol.h
 index 8ed77ac..81949ca 100644
 --- a/include/http_protocol.h
@@ -21,22 +26,40 @@ index 8ed77ac..81949ca 100644
   * Set the Accept-Ranges header for this response
   * @param r The current request
 diff --git a/include/httpd.h b/include/httpd.h
-index 99f7f04..a82560c 100644
+index 99f7f04..d8746c1 100644
 --- a/include/httpd.h
 +++ b/include/httpd.h
-@@ -699,6 +699,8 @@ struct ap_method_list_t {
- #define REQUEST_CHUNKED_DECHUNK  2
- /** @} // values_request_rec_body */
+@@ -645,6 +645,7 @@ struct ap_method_list_t {
+     /** the array used for extension methods */
+     apr_array_header_t *method_list;
+ };
++/** @} */
  
-+#define AP_REQUEST_TRUSTED_CT  1 << 1
-+
  /**
-  * @defgroup values_request_rec_used_path_info Possible values for request_rec.used_path_info
-  * @ingroup APACHE_CORE_DAEMON
-@@ -715,6 +717,12 @@ struct ap_method_list_t {
+  * @defgroup module_magic Module Magic mime types
+@@ -715,6 +716,31 @@ struct ap_method_list_t {
  
  /** @} // values_request_rec_used_path_info */
  
++#define AP_REQUEST_TRUSTED_CT  "rh-bnotes-trusted-ct"
++
++/**
++ * This is a convenience macro to ease with getting specific request
++ * binary notes.
++ */
++#define AP_REQUEST_GET_BNOTE(r, mask) (apr_table_get(r->notes, mask) ? 1 : 0)
++
++/**
++ * This is a convenience macro to ease with setting specific request
++ * binary notes.
++ */
++#define AP_REQUEST_SET_BNOTE(r, mask, val) do { \
++    if (val)                                    \
++        apr_table_setn(r->notes, mask, "1");    \
++    else                                        \
++        apr_table_unset(r->notes, mask);        \
++} while (0)
++
 +/**
 + * Returns true if the content-type field is from a trusted source
 + */
@@ -47,7 +70,7 @@ index 99f7f04..a82560c 100644
  /*
   * Things which may vary per file-lookup WITHIN a request ---
 diff --git a/modules/http/http_protocol.c b/modules/http/http_protocol.c
-index dcafa9c..417fee6 100644
+index df862e0..d003aea 100644
 --- a/modules/http/http_protocol.c
 +++ b/modules/http/http_protocol.c
 @@ -1077,8 +1077,14 @@ AP_DECLARE(void) ap_set_content_type(request_rec *r, const char *ct)