xref: /aosp_15_r20/external/cronet/net/spdy/header_coalescer.cc (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b)
1 // Copyright 2016 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "net/spdy/header_coalescer.h"
6 
7 #include <memory>
8 #include <string>
9 #include <string_view>
10 #include <utility>
11 
12 #include "base/ranges/algorithm.h"
13 #include "base/strings/string_util.h"
14 #include "base/strings/stringprintf.h"
15 #include "base/trace_event/memory_usage_estimator.h"
16 #include "base/values.h"
17 #include "net/http/http_log_util.h"
18 #include "net/http/http_util.h"
19 #include "net/log/net_log_values.h"
20 
21 namespace net {
22 namespace {
23 
NetLogInvalidHeader(const NetLogWithSource & net_log,std::string_view header_name,std::string_view header_value,const char * error_message)24 void NetLogInvalidHeader(const NetLogWithSource& net_log,
25                          std::string_view header_name,
26                          std::string_view header_value,
27                          const char* error_message) {
28   net_log.AddEvent(NetLogEventType::HTTP2_SESSION_RECV_INVALID_HEADER,
29                    [&](NetLogCaptureMode capture_mode) {
30                      return base::Value::Dict()
31                          .Set("header_name", NetLogStringValue(header_name))
32                          .Set("header_value",
33                               NetLogStringValue(ElideHeaderValueForNetLog(
34                                   capture_mode, std::string(header_name),
35                                   std::string(header_value))))
36                          .Set("error", error_message);
37                    });
38 }
39 
ContainsUppercaseAscii(std::string_view str)40 bool ContainsUppercaseAscii(std::string_view str) {
41   return base::ranges::any_of(str, base::IsAsciiUpper<char>);
42 }
43 
44 }  // namespace
45 
HeaderCoalescer(uint32_t max_header_list_size,const NetLogWithSource & net_log)46 HeaderCoalescer::HeaderCoalescer(uint32_t max_header_list_size,
47                                  const NetLogWithSource& net_log)
48     : max_header_list_size_(max_header_list_size), net_log_(net_log) {}
49 
OnHeader(std::string_view key,absl::string_view value)50 void HeaderCoalescer::OnHeader(std::string_view key, absl::string_view value) {
51   if (error_seen_)
52     return;
53   if (!AddHeader(key, value)) {
54     error_seen_ = true;
55   }
56 }
57 
release_headers()58 spdy::Http2HeaderBlock HeaderCoalescer::release_headers() {
59   DCHECK(headers_valid_);
60   headers_valid_ = false;
61   return std::move(headers_);
62 }
63 
AddHeader(std::string_view key,std::string_view value)64 bool HeaderCoalescer::AddHeader(std::string_view key, std::string_view value) {
65   if (key.empty()) {
66     NetLogInvalidHeader(net_log_, key, value, "Header name must not be empty.");
67     return false;
68   }
69 
70   std::string_view key_name = key;
71   if (key[0] == ':') {
72     if (regular_header_seen_) {
73       NetLogInvalidHeader(net_log_, key, value,
74                           "Pseudo header must not follow regular headers.");
75       return false;
76     }
77     key_name.remove_prefix(1);
78   } else if (!regular_header_seen_) {
79     regular_header_seen_ = true;
80   }
81 
82   if (!HttpUtil::IsValidHeaderName(key_name)) {
83     NetLogInvalidHeader(net_log_, key, value,
84                         "Invalid character in header name.");
85     return false;
86   }
87 
88   if (ContainsUppercaseAscii(key_name)) {
89     NetLogInvalidHeader(net_log_, key, value,
90                         "Upper case characters in header name.");
91     return false;
92   }
93 
94   // 32 byte overhead according to RFC 7540 Section 6.5.2.
95   header_list_size_ += key.size() + value.size() + 32;
96   if (header_list_size_ > max_header_list_size_) {
97     NetLogInvalidHeader(net_log_, key, value, "Header list too large.");
98     return false;
99   }
100 
101   // RFC 7540 Section 10.3: "Any request or response that contains a character
102   // not permitted in a header field value MUST be treated as malformed (Section
103   // 8.1.2.6). Valid characters are defined by the field-content ABNF rule in
104   // Section 3.2 of [RFC7230]." RFC 7230 Section 3.2 says:
105   // field-content  = field-vchar [ 1*( SP / HTAB ) field-vchar ]
106   // field-vchar    = VCHAR / obs-text
107   // RFC 5234 Appendix B.1 defines |VCHAR|:
108   // VCHAR          =  %x21-7E
109   // RFC 7230 Section 3.2.6 defines |obs-text|:
110   // obs-text       = %x80-FF
111   // Therefore allowed characters are '\t' (HTAB), x20 (SP), x21-7E, and x80-FF.
112   for (const unsigned char c : value) {
113     if (c < '\t' || ('\t' < c && c < 0x20) || c == 0x7f) {
114       std::string error_line;
115       base::StringAppendF(&error_line,
116                           "Invalid character 0x%02X in header value.", c);
117       NetLogInvalidHeader(net_log_, key, value, error_line.c_str());
118       return false;
119     }
120   }
121 
122   headers_.AppendValueOrAddHeader(key, value);
123   return true;
124 }
125 
126 }  // namespace net
127