src/proxyp/Elements.cc

   1 /*
   2  * Copyright (C) 1996-2020 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #include "squid.h"
  10 #include "parser/Tokenizer.h"
  11 #include "proxyp/Elements.h"
  12 #include "sbuf/Stream.h"
  13
  14 #include <algorithm>
  15 #include <limits>
  16 #include <vector>
  17
  18 namespace ProxyProtocol {
  19 namespace Two {
  20
  21 /// a mapping between pseudo header names and ids
  22 typedef std::vector< std::pair<SBuf, FieldType> > FieldMap;
  23 static const FieldMap PseudoHeaderFields = {
  24     { SBuf(":version"), htPseudoVersion },
  25     { SBuf(":command"), htPseudoCommand },
  26     { SBuf(":src_addr"), htPseudoSrcAddr },
  27     { SBuf(":dst_addr"), htPseudoDstAddr },
  28     { SBuf(":src_port"), htPseudoSrcPort },
  29     { SBuf(":dst_port"), htPseudoDstPort }
  30 };
  31
  32 } // namespace Two
  33
  34 static Two::FieldType NameToFieldType(const SBuf &);
  35 static Two::FieldType IntegerToFieldType(const SBuf &);
  36
  37 } // namespace ProxyProtocol
  38
  39 const SBuf &
  40 ProxyProtocol::PseudoFieldTypeToFieldName(const Two::FieldType fieldType)
  41 {
  42     const auto it = std::find_if(Two::PseudoHeaderFields.begin(), Two::PseudoHeaderFields.end(),
  43     [fieldType](const Two::FieldMap::value_type &item) {
  44         return item.second == fieldType;
  45     });
  46
  47     assert(it != Two::PseudoHeaderFields.end());
  48     return it->first;
  49 }
  50
  51 /// FieldNameToFieldType() helper that handles pseudo headers
  52 ProxyProtocol::Two::FieldType
  53 ProxyProtocol::NameToFieldType(const SBuf &name)
  54 {
  55     const auto it = std::find_if(Two::PseudoHeaderFields.begin(), Two::PseudoHeaderFields.end(),
  56     [&name](const Two::FieldMap::value_type &item) {
  57         return item.first == name;
  58     });
  59
  60     if (it != Two::PseudoHeaderFields.end())
  61         return it->second;
  62
  63     static const SBuf pseudoMark(":");
  64     if (name.startsWith(pseudoMark))
  65         throw TexcHere(ToSBuf("Unsupported PROXY protocol pseudo header: ", name));
  66
  67     throw TexcHere(ToSBuf("Invalid PROXY protocol pseudo header or TLV type name. ",
  68                           "Expected a pseudo header like :src_addr but got '", name, "'"));
  69 }
  70
  71 /// FieldNameToFieldType() helper that handles integer TLV types
  72 ProxyProtocol::Two::FieldType
  73 ProxyProtocol::IntegerToFieldType(const SBuf &rawInteger)
  74 {
  75     int64_t tlvType = 0;
  76
  77     Parser::Tokenizer ptok(rawInteger);
  78     if (ptok.skip('0')) {
  79         if (!ptok.atEnd())
  80             throw TexcHere(ToSBuf("Invalid PROXY protocol TLV type value. ",
  81                                   "Expected a decimal integer without leading zeros but got '",
  82                                   rawInteger, "'")); // e.g., 077, 0xFF, or 0b101
  83         // tlvType stays zero
  84     } else {
  85         Must(ptok.int64(tlvType, 10, false)); // the first character is a DIGIT
  86         if (!ptok.atEnd())
  87             throw TexcHere(ToSBuf("Invalid PROXY protocol TLV type value. ",
  88                                   "Trailing garbage after ", tlvType, " in '",
  89                                   rawInteger, "'")); // e.g., 1.0 or 5e0
  90     }
  91
  92     const auto limit = std::numeric_limits<uint8_t>::max();
  93     if (tlvType > limit)
  94         throw TexcHere(ToSBuf("Invalid PROXY protocol TLV type value. ",
  95                               "Expected an integer less than ", limit,
  96                               " but got '", tlvType, "'"));
  97
  98     return Two::FieldType(tlvType);
  99 }
 100
 101 ProxyProtocol::Two::FieldType
 102 ProxyProtocol::FieldNameToFieldType(const SBuf &tlvTypeRaw)
 103 {
 104     // we could branch on ":" instead of DIGIT but then field names that lack a
 105     // leading ":" (like "version") would get a less accurate error message
 106     return Parser::Tokenizer(tlvTypeRaw).skipOne(CharacterSet::DIGIT) ?
 107            IntegerToFieldType(tlvTypeRaw):
 108            NameToFieldType(tlvTypeRaw);
 109 }
 110