Botan  2.18.2
Crypto and TLS for C++11
asn1_alt_name.cpp
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1 /*
2 * AlternativeName
3 * (C) 1999-2007 Jack Lloyd
4 * 2007 Yves Jerschow
5 *
6 * Botan is released under the Simplified BSD License (see license.txt)
7 */
8 
9 #include <botan/pkix_types.h>
10 #include <botan/der_enc.h>
11 #include <botan/ber_dec.h>
12 #include <botan/oids.h>
13 #include <botan/internal/stl_util.h>
14 #include <botan/parsing.h>
15 #include <botan/loadstor.h>
16 
17 #include <sstream>
18 
19 namespace Botan {
20 
21 /*
22 * Create an AlternativeName
23 */
24 AlternativeName::AlternativeName(const std::string& email_addr,
25  const std::string& uri,
26  const std::string& dns,
27  const std::string& ip)
28  {
29  add_attribute("RFC822", email_addr);
30  add_attribute("DNS", dns);
31  add_attribute("URI", uri);
32  add_attribute("IP", ip);
33  }
34 
35 /*
36 * Add an attribute to an alternative name
37 */
38 void AlternativeName::add_attribute(const std::string& type,
39  const std::string& value)
40  {
41  if(type.empty() || value.empty())
42  return;
43 
44  auto range = m_alt_info.equal_range(type);
45  for(auto j = range.first; j != range.second; ++j)
46  if(j->second == value)
47  return;
48 
49  multimap_insert(m_alt_info, type, value);
50  }
51 
52 /*
53 * Add an OtherName field
54 */
55 void AlternativeName::add_othername(const OID& oid, const std::string& value,
56  ASN1_Tag type)
57  {
58  if(value.empty())
59  return;
60  multimap_insert(m_othernames, oid, ASN1_String(value, type));
61  }
62 
63 /*
64 * Return all of the alternative names
65 */
66 std::multimap<std::string, std::string> AlternativeName::contents() const
67  {
68  std::multimap<std::string, std::string> names;
69 
70  for(auto i = m_alt_info.begin(); i != m_alt_info.end(); ++i)
71  {
72  multimap_insert(names, i->first, i->second);
73  }
74 
75  for(auto i = m_othernames.begin(); i != m_othernames.end(); ++i)
76  {
77  multimap_insert(names, i->first.to_formatted_string(), i->second.value());
78  }
79 
80  return names;
81  }
82 
83 bool AlternativeName::has_field(const std::string& attr) const
84  {
85  auto range = m_alt_info.equal_range(attr);
86  return (range.first != range.second);
87  }
88 
89 std::string AlternativeName::get_first_attribute(const std::string& attr) const
90  {
91  auto i = m_alt_info.lower_bound(attr);
92  if(i != m_alt_info.end() && i->first == attr)
93  return i->second;
94 
95  return "";
96  }
97 
98 std::vector<std::string> AlternativeName::get_attribute(const std::string& attr) const
99  {
100  std::vector<std::string> results;
101  auto range = m_alt_info.equal_range(attr);
102  for(auto i = range.first; i != range.second; ++i)
103  results.push_back(i->second);
104  return results;
105  }
106 
108  {
109  X509_DN dn;
110  auto range = m_alt_info.equal_range("DN");
111 
112  for(auto i = range.first; i != range.second; ++i)
113  {
114  std::istringstream strm(i->second);
115  strm >> dn;
116  }
117 
118  return dn;
119  }
120 
121 /*
122 * Return if this object has anything useful
123 */
125  {
126  return (m_alt_info.size() > 0 || m_othernames.size() > 0);
127  }
128 
129 namespace {
130 
131 /*
132 * DER encode an AlternativeName entry
133 */
134 void encode_entries(DER_Encoder& encoder,
135  const std::multimap<std::string, std::string>& attr,
136  const std::string& type, ASN1_Tag tagging)
137  {
138  auto range = attr.equal_range(type);
139 
140  for(auto i = range.first; i != range.second; ++i)
141  {
142  if(type == "RFC822" || type == "DNS" || type == "URI")
143  {
144  ASN1_String asn1_string(i->second, IA5_STRING);
145  encoder.add_object(tagging, CONTEXT_SPECIFIC, asn1_string.value());
146  }
147  else if(type == "IP")
148  {
149  const uint32_t ip = string_to_ipv4(i->second);
150  uint8_t ip_buf[4] = { 0 };
151  store_be(ip, ip_buf);
152  encoder.add_object(tagging, CONTEXT_SPECIFIC, ip_buf, 4);
153  }
154  else if (type == "DN")
155  {
156  std::stringstream ss(i->second);
157  X509_DN dn;
158  ss >> dn;
159  encoder.encode(dn);
160  }
161  }
162  }
163 
164 }
165 
166 /*
167 * DER encode an AlternativeName extension
168 */
170  {
171  der.start_cons(SEQUENCE);
172 
173  encode_entries(der, m_alt_info, "RFC822", ASN1_Tag(1));
174  encode_entries(der, m_alt_info, "DNS", ASN1_Tag(2));
175  encode_entries(der, m_alt_info, "DN", ASN1_Tag(4));
176  encode_entries(der, m_alt_info, "URI", ASN1_Tag(6));
177  encode_entries(der, m_alt_info, "IP", ASN1_Tag(7));
178 
179  for(auto i = m_othernames.begin(); i != m_othernames.end(); ++i)
180  {
181  der.start_explicit(0)
182  .encode(i->first)
183  .start_explicit(0)
184  .encode(i->second)
185  .end_explicit()
186  .end_explicit();
187  }
188 
189  der.end_cons();
190  }
191 
192 /*
193 * Decode a BER encoded AlternativeName
194 */
196  {
197  BER_Decoder names = source.start_cons(SEQUENCE);
198 
199  // FIXME this is largely a duplication of GeneralName::decode_from
200 
201  while(names.more_items())
202  {
203  BER_Object obj = names.get_next_object();
204 
205  if(obj.is_a(0, CONTEXT_SPECIFIC))
206  {
207  BER_Decoder othername(obj);
208 
209  OID oid;
210  othername.decode(oid);
211  if(othername.more_items())
212  {
213  BER_Object othername_value_outer = othername.get_next_object();
214  othername.verify_end();
215 
216  if(othername_value_outer.is_a(0, ASN1_Tag(CONTEXT_SPECIFIC | CONSTRUCTED)) == false)
217  throw Decoding_Error("Invalid tags on otherName value");
218 
219  BER_Decoder othername_value_inner(othername_value_outer);
220 
221  BER_Object value = othername_value_inner.get_next_object();
222  othername_value_inner.verify_end();
223 
224  if(ASN1_String::is_string_type(value.type()) && value.get_class() == UNIVERSAL)
225  {
226  add_othername(oid, ASN1::to_string(value), value.type());
227  }
228  }
229  }
230  if(obj.is_a(1, CONTEXT_SPECIFIC))
231  {
232  add_attribute("RFC822", ASN1::to_string(obj));
233  }
234  else if(obj.is_a(2, CONTEXT_SPECIFIC))
235  {
236  add_attribute("DNS", ASN1::to_string(obj));
237  }
238  else if(obj.is_a(6, CONTEXT_SPECIFIC))
239  {
240  add_attribute("URI", ASN1::to_string(obj));
241  }
242  else if(obj.is_a(4, ASN1_Tag(CONTEXT_SPECIFIC | CONSTRUCTED)))
243  {
244  BER_Decoder dec(obj);
245  X509_DN dn;
246  std::stringstream ss;
247 
248  dec.decode(dn);
249  ss << dn;
250 
251  add_attribute("DN", ss.str());
252  }
253  else if(obj.is_a(7, CONTEXT_SPECIFIC))
254  {
255  if(obj.length() == 4)
256  {
257  const uint32_t ip = load_be<uint32_t>(obj.bits(), 0);
258  add_attribute("IP", ipv4_to_string(ip));
259  }
260  }
261 
262  }
263  }
264 
265 }
DER_Encoder & add_object(ASN1_Tag type_tag, ASN1_Tag class_tag, const uint8_t rep[], size_t length)
Definition: der_enc.cpp:249
void decode_from(BER_Decoder &) override
static bool is_string_type(ASN1_Tag tag)
Definition: asn1_str.cpp:68
void add_othername(const OID &oid, const std::string &value, ASN1_Tag type)
void store_be(uint16_t in, uint8_t out[2])
Definition: loadstor.h:438
bool is_a(ASN1_Tag type_tag, ASN1_Tag class_tag) const
Definition: asn1_obj.cpp:71
void add_attribute(const std::string &type, const std::string &value)
uint32_t load_be< uint32_t >(const uint8_t in[], size_t off)
Definition: loadstor.h:179
std::multimap< std::string, std::string > contents() const
DER_Encoder & end_explicit()
Definition: der_enc.cpp:220
std::string to_string(const BER_Object &obj)
Definition: asn1_obj.cpp:213
ASN1_Tag
Definition: asn1_obj.h:25
MechanismType type
DER_Encoder & end_cons()
Definition: der_enc.cpp:191
BER_Decoder & decode(bool &out)
Definition: ber_dec.h:170
ASN1_Tag type() const
Definition: asn1_obj.h:116
DER_Encoder & encode(bool b)
Definition: der_enc.cpp:285
ASN1_Tag get_class() const
Definition: asn1_obj.h:117
std::string ipv4_to_string(uint32_t ip)
Definition: parsing.cpp:278
std::vector< std::string > get_attribute(const std::string &attr) const
AlternativeName(const std::string &email_addr="", const std::string &uri="", const std::string &dns="", const std::string &ip_address="")
BER_Decoder start_cons(ASN1_Tag type_tag, ASN1_Tag class_tag=UNIVERSAL)
Definition: ber_dec.cpp:290
size_t length() const
Definition: asn1_obj.h:121
Definition: alg_id.cpp:13
uint32_t string_to_ipv4(const std::string &str)
Definition: parsing.cpp:253
BER_Object get_next_object()
Definition: ber_dec.cpp:237
const uint8_t * bits() const
Definition: asn1_obj.h:119
std::string get_first_attribute(const std::string &attr) const
BER_Decoder & verify_end()
Definition: ber_dec.cpp:208
DER_Encoder & start_cons(ASN1_Tag type_tag, ASN1_Tag class_tag=UNIVERSAL)
Definition: der_enc.cpp:181
void multimap_insert(std::multimap< K, V > &multimap, const K &key, const V &value)
Definition: stl_util.h:76
bool has_field(const std::string &attr) const
bool more_items() const
Definition: ber_dec.cpp:198
void encode_into(DER_Encoder &) const override
DER_Encoder & start_explicit(uint16_t type_tag)
Definition: der_enc.cpp:206