http_client: rewrite header parsing manually for speed

boost::regex is stupendously atrocious at parsing malformed data

1 files changed, 95 insertions, 74 deletions

diff --git a/contrib/epee/include/net/http_client.h b/contrib/epee/include/net/http_client.h
index 5c448fcb3..1edf65928 100644
--- a/contrib/epee/include/net/http_client.h
+++ b/contrib/epee/include/net/http_client.h
@@ -27,6 +27,7 @@
 
 
 #pragma once
+#include <ctype.h>
 #include <boost/shared_ptr.hpp>
 #include <boost/regex.hpp>
 #include <boost/lexical_cast.hpp>
@@ -752,87 +753,107 @@ namespace net_utils
 				return true;
 			}
 			//---------------------------------------------------------------------------
-			inline
-				bool parse_header(http_header_info& body_info, const std::string& m_cache_to_process)
-			{ 
+			inline bool parse_header(http_header_info& body_info, const std::string& m_cache_to_process)
+			{
 				MTRACE("http_stream_filter::parse_cached_header(*)");
-				
-				STATIC_REGEXP_EXPR_1(rexp_mach_field, 
-					"\n?((Connection)|(Referer)|(Content-Length)|(Content-Type)|(Transfer-Encoding)|(Content-Encoding)|(Host)|(Cookie)|(User-Agent)|(Origin)"
-					//  12            3         4                5              6                   7                  8      9        10            11
-					"|([\\w-]+?)) ?: ?((.*?)(\r?\n))[^\t ]",	
-					//12             13 14   15
-					boost::regex::icase | boost::regex::normal);
-
-				boost::smatch		result;
-				std::string::const_iterator it_current_bound = m_cache_to_process.begin();
-				std::string::const_iterator it_end_bound = m_cache_to_process.end();
 
-
-
-				//lookup all fields and fill well-known fields
-				while( boost::regex_search( it_current_bound, it_end_bound, result, rexp_mach_field, boost::match_default) && result[0].matched) 
+				const char *ptr = m_cache_to_process.c_str();
+				while (ptr[0] != '\r' || ptr[1] != '\n')
 				{
-					const size_t field_val = 14;
-					//const size_t field_etc_name = 11;
-
-					int i = 2; //start position = 2
-					if(result[i++].matched)//"Connection"
-						body_info.m_connection = result[field_val];
-					else if(result[i++].matched)//"Referrer"
-						body_info.m_referer = result[field_val];
-					else if(result[i++].matched)//"Content-Length"
-						body_info.m_content_length = result[field_val];
-					else if(result[i++].matched)//"Content-Type"
-						body_info.m_content_type = result[field_val];
-					else if(result[i++].matched)//"Transfer-Encoding"
-						body_info.m_transfer_encoding = result[field_val];
-					else if(result[i++].matched)//"Content-Encoding"
-						body_info.m_content_encoding = result[field_val];
-					else if(result[i++].matched)//"Host"
-					{	body_info.m_host = result[field_val];
-					string_tools::trim(body_info.m_host);
+					// optional \n
+					if (*ptr == '\n')
+						++ptr;
+					// an identifier composed of letters or -
+					const char *key_pos = ptr;
+					while (isalnum(*ptr) || *ptr == '_' || *ptr == '-')
+						++ptr;
+					const char *key_end = ptr;
+					// optional space (not in RFC, but in previous code)
+					if (*ptr == ' ')
+						++ptr;
+					CHECK_AND_ASSERT_MES(*ptr == ':', true, "http_stream_filter::parse_cached_header() invalid header in: " << m_cache_to_process);
+					++ptr;
+					// optional whitespace, but not newlines - line folding is obsolete, let's ignore it
+					while (isblank(*ptr))
+						++ptr;
+					const char *value_pos = ptr;
+					while (*ptr != '\r' && *ptr != '\n')
+						++ptr;
+					const char *value_end = ptr;
+					// optional trailing whitespace
+					while (value_end > value_pos && isblank(*(value_end-1)))
+						--value_end;
+					if (*ptr == '\r')
+						++ptr;
+					CHECK_AND_ASSERT_MES(*ptr == '\n', true, "http_stream_filter::parse_cached_header() invalid header in: " << m_cache_to_process);
+					++ptr;
+
+					const std::string key = std::string(key_pos, key_end - key_pos);
+					const std::string value = std::string(value_pos, value_end - value_pos);
+					if (!key.empty())
+					{
+						if (!string_tools::compare_no_case(key, "Connection"))
+							body_info.m_connection = value;
+						else if(!string_tools::compare_no_case(key, "Referrer"))
+							body_info.m_referer = value;
+						else if(!string_tools::compare_no_case(key, "Content-Length"))
+							body_info.m_content_length = value;
+						else if(!string_tools::compare_no_case(key, "Content-Type"))
+							body_info.m_content_type = value;
+						else if(!string_tools::compare_no_case(key, "Transfer-Encoding"))
+							body_info.m_transfer_encoding = value;
+						else if(!string_tools::compare_no_case(key, "Content-Encoding"))
+							body_info.m_content_encoding = value;
+						else if(!string_tools::compare_no_case(key, "Host"))
+							body_info.m_host = value;
+						else if(!string_tools::compare_no_case(key, "Cookie"))
+							body_info.m_cookie = value;
+						else if(!string_tools::compare_no_case(key, "User-Agent"))
+							body_info.m_user_agent = value;
+						else if(!string_tools::compare_no_case(key, "Origin"))
+							body_info.m_origin = value;
+						else
+							body_info.m_etc_fields.emplace_back(key, value);
 					}
-					else if(result[i++].matched)//"Cookie"
-						body_info.m_cookie = result[field_val];
-					else if(result[i++].matched)//"User-Agent"
-						body_info.m_user_agent = result[field_val];
-					else if(result[i++].matched)//"Origin"
-						body_info.m_origin = result[field_val];
-					else if(result[i++].matched)//e.t.c (HAVE TO BE MATCHED!)
-						body_info.m_etc_fields.emplace_back(result[12], result[field_val]);
-					else
-					{CHECK_AND_ASSERT_MES(false, false, "http_stream_filter::parse_cached_header() not matched last entry in:"<<m_cache_to_process);}
-
-					it_current_bound = result[(int)result.size()-1]. first;
 				}
-				return  true;
-
+				return true;
 			}
-			inline
-				bool analize_first_response_line()
+			//---------------------------------------------------------------------------
+			inline bool analize_first_response_line()
 			{
-
-				//First line response, look like this:  "HTTP/1.1 200 OK"
-				STATIC_REGEXP_EXPR_1(rexp_match_first_response_line, "^HTTP/(\\d+).(\\d+) ((\\d)\\d{2})( [^\n]*)?\r?\n", boost::regex::icase | boost::regex::normal);
-				//															1      2      34           5        
-				//size_t match_len = 0;
-				boost::smatch result;
-				if(boost::regex_search( m_header_cache, result, rexp_match_first_response_line, boost::match_default) && result[0].matched)
-				{
-					CHECK_AND_ASSERT_MES(result[1].matched&&result[2].matched, false, "http_stream_filter::handle_invoke_reply_line() assert failed...");
-					m_response_info.m_http_ver_hi   = boost::lexical_cast<int>(result[1]);
-					m_response_info.m_http_ver_lo   = boost::lexical_cast<int>(result[2]);
-					m_response_info.m_response_code = boost::lexical_cast<int>(result[3]);
-					
-					m_header_cache.erase(to_nonsonst_iterator(m_header_cache, result[0].first), to_nonsonst_iterator(m_header_cache, result[0].second));
-					return true;
-				}else
-				{
-					LOG_ERROR("http_stream_filter::handle_invoke_reply_line(): Failed to match first response line:" << m_header_cache);
-					return false;
-				}
-
+				//First line response, look like this:	"HTTP/1.1 200 OK"
+				const char *ptr = m_header_cache.c_str();
+				CHECK_AND_ASSERT_MES(!memcmp(ptr, "HTTP/", 5), false, "Invalid first response line: " + m_header_cache);
+				ptr += 5;
+				CHECK_AND_ASSERT_MES(isdigit(*ptr), false, "Invalid first response line: " + m_header_cache);
+				unsigned long ul;
+				char *end;
+				ul = strtoul(ptr, &end, 10);
+				CHECK_AND_ASSERT_MES(ul <= INT_MAX && *end =='.', false, "Invalid first response line: " + m_header_cache);
+				m_response_info.m_http_ver_hi = ul;
+				ptr = end + 1;
+				CHECK_AND_ASSERT_MES(isdigit(*ptr), false, "Invalid first response line: " + m_header_cache + ", ptr: " << ptr);
+				ul = strtoul(ptr, &end, 10);
+				CHECK_AND_ASSERT_MES(ul <= INT_MAX && isblank(*end), false, "Invalid first response line: " + m_header_cache + ", ptr: " << ptr);
+				m_response_info.m_http_ver_lo = ul;
+				ptr = end + 1;
+				while (isblank(*ptr))
+					++ptr;
+				CHECK_AND_ASSERT_MES(isdigit(*ptr), false, "Invalid first response line: " + m_header_cache);
+				ul = strtoul(ptr, &end, 10);
+				CHECK_AND_ASSERT_MES(ul >= 100 && ul <= 999 && isspace(*end), false, "Invalid first response line: " + m_header_cache);
+				m_response_info.m_response_code = ul;
+				ptr = end;
+				// ignore the optional text, till the end
+				while (*ptr != '\r' && *ptr != '\n')
+					++ptr;
+				if (*ptr == '\r')
+					++ptr;
+				CHECK_AND_ASSERT_MES(*ptr == '\n', false, "Invalid first response line: " << m_header_cache);
+				++ptr;
+
+				m_header_cache.erase(0, ptr - m_header_cache.c_str());
+				return true;
 			}
 			inline
 				bool set_reply_content_encoder()