validation-policy.cpp
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21 
24 
25 namespace ndn {
26 namespace security {
27 inline namespace v2 {
28 
29 void
30 ValidationPolicy::setInnerPolicy(unique_ptr<ValidationPolicy> innerPolicy)
31 {
32  if (innerPolicy == nullptr) {
33  NDN_THROW(std::invalid_argument("Inner policy argument cannot be nullptr"));
34  }
35 
36  if (m_validator != nullptr) {
37  innerPolicy->setValidator(*m_validator);
38  }
39 
40  if (m_innerPolicy == nullptr) {
41  m_innerPolicy = std::move(innerPolicy);
42  }
43  else {
44  m_innerPolicy->setInnerPolicy(std::move(innerPolicy));
45  }
46 }
47 
50 {
51  return *m_innerPolicy;
52 }
53 
54 void
56 {
57  m_validator = &validator;
58  if (m_innerPolicy != nullptr) {
59  m_innerPolicy->setValidator(validator);
60  }
61 }
62 
63 Name
65 {
66  if (si.getSignatureType() == tlv::DigestSha256) {
68  }
69 
70  if (!si.hasKeyLocator()) {
71  state.fail({ValidationError::INVALID_KEY_LOCATOR, "KeyLocator is missing"});
72  return {};
73  }
74 
75  const KeyLocator& kl = si.getKeyLocator();
76  if (kl.getType() != tlv::Name) {
77  state.fail({ValidationError::INVALID_KEY_LOCATOR, "KeyLocator type is not Name"});
78  return {};
79  }
80 
81  return kl.getName();
82 }
83 
85 getSignatureInfo(const Interest& interest, ValidationState& state)
86 {
87  auto fmt = state.getTag<SignedInterestFormatTag>();
88  BOOST_ASSERT(fmt);
89 
90  if (*fmt == SignedInterestFormat::V03) {
91  BOOST_ASSERT(interest.getSignatureInfo().has_value());
92  return *interest.getSignatureInfo();
93  }
94 
95  // Try the old Signed Interest format from Packet Specification v0.2
96  const Name& name = interest.getName();
97  if (name.size() < signed_interest::MIN_SIZE) {
99  "Interest name too short `" + name.toUri() + "`"});
100  return {};
101  }
102 
103  try {
104  return SignatureInfo(name[signed_interest::POS_SIG_INFO].blockFromValue());
105  }
106  catch (const tlv::Error& e) {
108  "Malformed SignatureInfo in `" + name.toUri() + "`: " + e.what()});
109  return {};
110  }
111 }
112 
113 Name
115 {
116  // handling special cases
117  if (keyLocator == SigningInfo::getDigestSha256Identity() ||
118  keyLocator == SigningInfo::getHmacIdentity()) {
119  return keyLocator;
120  }
121 
122  auto len = static_cast<ssize_t>(keyLocator.size());
123  // note that KEY_COMPONENT_OFFSET is negative
124  auto lowerBound = std::max<ssize_t>(len + Certificate::KEY_COMPONENT_OFFSET, 0);
125  for (ssize_t i = len - 1; i >= lowerBound; --i) {
126  if (keyLocator[i] == Certificate::KEY_COMPONENT) {
127  return keyLocator.getPrefix(i);
128  }
129  }
130 
131  NDN_THROW(KeyLocator::Error("KeyLocator `" + keyLocator.toUri() +
132  "` does not respect the naming conventions"));
133 }
134 
135 } // inline namespace v2
136 } // namespace security
137 } // namespace ndn
Represents an Interest packet.
Definition: interest.hpp:50
const Name & getName() const noexcept
Definition: interest.hpp:173
optional< SignatureInfo > getSignatureInfo() const
Get the InterestSignatureInfo element.
Definition: interest.cpp:531
const Name & getName() const
Get nested Name element.
uint32_t getType() const
Represents an absolute name.
Definition: name.hpp:44
PartialName getPrefix(ssize_t nComponents) const
Returns a prefix of the name.
Definition: name.hpp:216
size_t size() const noexcept
Returns the number of components.
Definition: name.hpp:155
void toUri(std::ostream &os, name::UriFormat format=name::UriFormat::DEFAULT) const
Write URI representation of the name to the output stream.
Definition: name.cpp:349
Represents a SignatureInfo or InterestSignatureInfo TLV element.
int32_t getSignatureType() const noexcept
Get the SignatureType.
bool hasKeyLocator() const noexcept
Check if KeyLocator is present.
const KeyLocator & getKeyLocator() const
Get the KeyLocator element.
Provides a tag type for simple types.
Definition: tag.hpp:56
shared_ptr< T > getTag() const
Get a tag item.
Definition: tag-host.hpp:67
static const Name & getDigestSha256Identity()
A localhost identity to indicate that the signature is generated using SHA-256.
static const Name & getHmacIdentity()
A localhost identity to indicate that the signature is generated using an HMAC key.
static const name::Component KEY_COMPONENT
static const ssize_t KEY_COMPONENT_OFFSET
@ MALFORMED_SIGNATURE
The signature (e.g., SignatureInfo element) is missing or malformed.
@ INVALID_KEY_LOCATOR
The KeyLocator element is missing or has an invalid format.
Abstraction that implements a validation policy for Interest and Data packets.
ValidationPolicy & getInnerPolicy()
Return the inner policy.
void setValidator(Validator &validator)
Set validator to which the policy is associated.
unique_ptr< ValidationPolicy > m_innerPolicy
void setInnerPolicy(unique_ptr< ValidationPolicy > innerPolicy)
Set inner policy.
virtual void fail(const ValidationError &error)=0
Call the failure callback.
Interface for validating data and interest packets.
Definition: validator.hpp:62
Represents an error in TLV encoding or decoding.
Definition: tlv.hpp:54
#define NDN_THROW(e)
Definition: exception.hpp:61
Name getKeyLocatorName(const SignatureInfo &si, ValidationState &state)
Extract the KeyLocator name from a SignatureInfo element.
SignatureInfo getSignatureInfo(const Interest &interest, ValidationState &state)
Extract SignatureInfo from a signed Interest.
Name extractIdentityNameFromKeyLocator(const Name &keyLocator)
Extract identity name from key, version-less certificate, or certificate name.
@ V03
Sign Interest using Packet Specification v0.3 semantics.
const size_t MIN_SIZE
Minimum number of name components for an old-style Signed Interest.
const ssize_t POS_SIG_INFO
@ Name
Definition: tlv.hpp:71
@ SignatureInfo
Definition: tlv.hpp:94
@ DigestSha256
Definition: tlv.hpp:128
Definition: data.cpp:25