Kea  2.1.7-git
dhcp4/parser_context.cc
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1 // Copyright (C) 2016-2021 Internet Systems Consortium, Inc. ("ISC")
2 //
3 // This Source Code Form is subject to the terms of the Mozilla Public
4 // License, v. 2.0. If a copy of the MPL was not distributed with this
5 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
6 
7 #include <config.h>
8 
9 #include <dhcp4/parser_context.h>
10 #include <dhcp4/dhcp4_parser.h>
11 #include <dhcp4/dhcp4_log.h>
12 #include <exceptions/exceptions.h>
13 #include <cc/data.h>
14 #include <boost/lexical_cast.hpp>
15 #include <fstream>
16 #include <sstream>
17 #include <limits>
18 
19 namespace isc {
20 namespace dhcp {
21 
23  : sfile_(nullptr), ctx_(NO_KEYWORD), trace_scanning_(false),
24  trace_parsing_(false) {
25 }
26 
28 }
29 
31 Parser4Context::parseString(const std::string& str, ParserType parser_type) {
32  scanStringBegin(str, parser_type);
33  return (parseCommon());
34 }
35 
37 Parser4Context::parseFile(const std::string& filename, ParserType parser_type) {
38  FILE* f = fopen(filename.c_str(), "r");
39  if (!f) {
40  isc_throw(Dhcp4ParseError, "Unable to open file " << filename);
41  }
42  scanFileBegin(f, filename, parser_type);
43  return (parseCommon());
44 }
45 
47 Parser4Context::parseCommon() {
48  isc::dhcp::Dhcp4Parser parser(*this);
49  // Uncomment this to get detailed parser logs.
50  // trace_parsing_ = true;
51  parser.set_debug_level(trace_parsing_);
52  try {
53  int res = parser.parse();
54  if (res != 0) {
55  isc_throw(Dhcp4ParseError, "Parser abort");
56  }
57  scanEnd();
58  }
59  catch (...) {
60  scanEnd();
61  throw;
62  }
63  if (stack_.size() == 1) {
64  return (stack_[0]);
65  } else {
66  isc_throw(Dhcp4ParseError, "Expected exactly one terminal Element expected, found "
67  << stack_.size());
68  }
69 }
70 
71 void
72 Parser4Context::error(const isc::dhcp::location& loc,
73  const std::string& what,
74  size_t pos) {
75  if (pos == 0) {
76  isc_throw(Dhcp4ParseError, loc << ": " << what);
77  } else {
78  isc_throw(Dhcp4ParseError, loc << " (near " << pos << "): " << what);
79  }
80 }
81 
82 void
83 Parser4Context::error(const std::string& what) {
85 }
86 
87 void
88 Parser4Context::fatal(const std::string& what) {
90 }
91 
93 Parser4Context::loc2pos(isc::dhcp::location& loc) {
94  const std::string& file = *loc.begin.filename;
95  const uint32_t line = loc.begin.line;
96  const uint32_t pos = loc.begin.column;
97  return (isc::data::Element::Position(file, line, pos));
98 }
99 
100 void
101 Parser4Context::require(const std::string& name,
103  isc::data::Element::Position close_loc) {
104  ConstElementPtr value = stack_.back()->get(name);
105  if (!value) {
107  "missing parameter '" << name << "' ("
108  << stack_.back()->getPosition() << ") ["
109  << contextName() << " map between "
110  << open_loc << " and " << close_loc << "]");
111  }
112 }
113 
114 void
115 Parser4Context::unique(const std::string& name,
117  ConstElementPtr value = stack_.back()->get(name);
118  if (value) {
119  if (ctx_ != NO_KEYWORD) {
120  isc_throw(Dhcp4ParseError, loc << ": duplicate " << name
121  << " entries in " << contextName()
122  << " map (previous at " << value->getPosition() << ")");
123  } else {
124  isc_throw(Dhcp4ParseError, loc << ": duplicate " << name
125  << " entries in JSON"
126  << " map (previous at " << value->getPosition() << ")");
127  }
128 
129  }
130 }
131 
132 void
134  cstack_.push_back(ctx_);
135  ctx_ = ctx;
136 }
137 
138 void
140 #if 1
141  if (cstack_.empty()) {
142  fatal("unbalanced syntactic context");
143  }
144 #endif
145  ctx_ = cstack_.back();
146  cstack_.pop_back();
147 }
148 
149 const std::string
151  switch (ctx_) {
152  case NO_KEYWORD:
153  return ("__no keyword__");
154  case CONFIG:
155  return ("toplevel");
156  case DHCP4:
157  return ("Dhcp4");
158  case INTERFACES_CONFIG:
159  return ("interfaces-config");
160  case DHCP_SOCKET_TYPE:
161  return ("dhcp-socket-type");
162  case OUTBOUND_INTERFACE:
163  return ("outbound-interface");
164  case LEASE_DATABASE:
165  return ("lease-database");
166  case HOSTS_DATABASE:
167  return ("hosts-database");
168  case DATABASE_TYPE:
169  return ("database-type");
170  case DATABASE_ON_FAIL:
171  return ("database-on-fail");
173  return ("host-reservation-identifiers");
174  case HOOKS_LIBRARIES:
175  return ("hooks-libraries");
176  case SUBNET4:
177  return ("subnet4");
178  case RESERVATION_MODE:
179  return ("reservation-mode");
180  case OPTION_DEF:
181  return ("option-def");
182  case OPTION_DATA:
183  return ("option-data");
184  case CLIENT_CLASSES:
185  return ("client-classes");
187  return ("expired-leases-processing");
188  case SERVER_ID:
189  return ("server-id");
190  case CONTROL_SOCKET:
191  return ("control-socket");
192  case DHCP_QUEUE_CONTROL:
193  return ("dhcp-queue-control");
195  return ("multi-threading");
196  case POOLS:
197  return ("pools");
198  case RESERVATIONS:
199  return ("reservations");
200  case RELAY:
201  return ("relay");
202  case LOGGERS:
203  return ("loggers");
204  case OUTPUT_OPTIONS:
205  return ("output-options");
206  case DHCP_DDNS:
207  return ("dhcp-ddns");
208  case NCR_PROTOCOL:
209  return ("ncr-protocol");
210  case NCR_FORMAT:
211  return ("ncr-format");
212  case REPLACE_CLIENT_NAME:
213  return ("replace-client-name");
214  case SHARED_NETWORK:
215  return ("shared-networks");
216  case SANITY_CHECKS:
217  return ("sanity-checks");
218  case CONFIG_CONTROL:
219  return ("config-control");
220  case CONFIG_DATABASE:
221  return ("config-database");
222  case COMPATIBILITY:
223  return ("compatibility");
224  default:
225  return ("__unknown__");
226  }
227 }
228 
229 void
230 Parser4Context::warning(const isc::dhcp::location& loc,
231  const std::string& what) {
232  std::ostringstream msg;
233  msg << loc << ": " << what;
235  .arg(msg.str());
236 }
237 
238 void
239 Parser4Context::warnAboutExtraCommas(const isc::dhcp::location& loc) {
240  warning(loc, "Extraneous comma. A piece of configuration may have been omitted.");
241 }
242 
243 } // namespace dhcp
244 } // namespace isc
Used while parsing Dhcp4/hosts-database[s] structures.
Used while parsing Dhcp4/*-database/on-fail.
#define LOG_WARN(LOGGER, MESSAGE)
Macro to conveniently test warn output and log it.
Definition: macros.h:26
Used while parsing Dhcp4/dhcp-ddns/ncr-protocol.
Used while parsing Dhcp4/hooks-libraries.
ParserContext
Defines syntactic contexts for lexical tie-ins.
void leave()
Leave a syntactic context.
Used while parsing Dhcp4/dhcp-ddns/ncr-format.
isc::data::ElementPtr parseFile(const std::string &filename, ParserType parser_type)
Run the parser on the file specified.
Used while parsing Dhcp4/interfaces/outbound-interface structures.
Used while parsing Dhcp4/client-classes structures.
const std::string contextName()
Get the syntactic context name.
isc::data::Element::Position loc2pos(isc::dhcp::location &loc)
Converts bison&#39;s position to one understandable by isc::data::Element.
Used while parsing Dhcp4/*-database/type.
Used while parsing Dhcp4/host-reservation-identifiers.
Used while parsing Dhcp4/multi-threading structures.
boost::shared_ptr< Element > ElementPtr
Definition: data.h:24
void enter(const ParserContext &ctx)
Enter a new syntactic context.
Used while parsing Dhcp4/reservations structures.
Used while parsing Dhcp4/lease-database structures.
void scanEnd()
Method called after the last tokens are scanned.
Used while parsing Dhcp4/dhcp-ddns.
Used while parsing Dhcp4/interfaces/dhcp-socket-type structures.
Used while parsing Dhcp4/server-id structures.
isc::data::ElementPtr parseString(const std::string &str, ParserType parser_type)
Run the parser on the string specified.
Define the isc::dhcp::parser class.
Used while parsing Dhcp4/control-socket structures.
virtual int parse()
Parse.
isc::log::Logger dhcp4_logger(DHCP4_APP_LOGGER_NAME)
Base logger for DHCPv4 server.
Definition: dhcp4_log.h:90
Used while parsing Dhcp4/subnet4/pools structures.
Parser4Context()
Default constructor.
Used while parsing Dhcp4/dhcp-queue-control structures.
Used while parsing shared-networks structures.
#define isc_throw(type, stream)
A shortcut macro to insert known values into exception arguments.
ParserContext ctx_
Current syntactic context.
std::vector< isc::data::ElementPtr > stack_
JSON elements being parsed.
Used while parsing Dhcp4/dhcp-ddns/replace-client-name.
Used while parsing Dhcp4/loggers/output_options structures.
ParserType
Defines currently supported scopes.
boost::shared_ptr< const Element > ConstElementPtr
Definition: data.h:27
Used while parsing Dhcp4/Subnet4 structures.
void scanFileBegin(FILE *f, const std::string &filename, ParserType type)
Method called before scanning starts on a file.
Evaluation error exception raised when trying to parse.
Used while parsing Dhcp4/option-def structures.
Used while parsing Dhcp4/option-data, Dhcp4/subnet4/option-data or anywhere option-data is present (c...
Used while parsing Dhcp4/interfaces structures.
Used while parsing content of Dhcp4.
Represents the position of the data element within a configuration string.
Definition: data.h:92
Used while parsing Dhcp4/subnet4relay structures.
void require(const std::string &name, isc::data::Element::Position open_loc, isc::data::Element::Position close_loc)
Check if a required parameter is present.
Defines the logger used by the top-level component of kea-lfc.
A Bison parser.
Definition: dhcp4_parser.h:215
void set_debug_level(debug_level_type l)
Set the current debugging level.
void warnAboutExtraCommas(const isc::dhcp::location &loc)
Warning for extra commas.
Used while parsing Dhcp4/loggers structures.
This one is used in pure JSON mode.
Used while parsing compatibility parameters.
void scanStringBegin(const std::string &str, ParserType type)
Method called before scanning starts on a string.
void unique(const std::string &name, isc::data::Element::Position loc)
Check if a parameter is already present.
void error(const isc::dhcp::location &loc, const std::string &what, size_t pos=0)
Error handler.
Used while parsing Dhcp4/expired-leases-processing.
Used while parsing config-control/config-databases.
static void fatal(const std::string &what)
Fatal error handler.
Contains declarations for loggers used by the DHCPv4 server component.
virtual ~Parser4Context()
destructor
Used while parsing Dhcp4/config-control.
Used while parsing Dhcp4/reservation-mode.
void warning(const isc::dhcp::location &loc, const std::string &what)
Warning handler.
const isc::log::MessageID DHCP4_CONFIG_SYNTAX_WARNING