signer-filter.cpp
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21 
24 #include "ndn-cxx/security/impl/openssl-helper.hpp"
25 
26 #include <boost/lexical_cast.hpp>
27 
28 namespace ndn {
29 namespace security {
30 namespace transform {
31 
32 class SignerFilter::Impl
33 {
34 public:
35  detail::EvpMdCtx ctx;
36 };
37 
38 
40  : m_impl(make_unique<Impl>())
41 {
42  const EVP_MD* md = detail::digestAlgorithmToEvpMd(algo);
43  if (md == nullptr)
44  NDN_THROW(Error(getIndex(), "Unsupported digest algorithm " +
45  boost::lexical_cast<std::string>(algo)));
46 
47  if (EVP_DigestSignInit(m_impl->ctx, nullptr, md, nullptr,
48  reinterpret_cast<EVP_PKEY*>(key.getEvpPkey())) != 1)
49  NDN_THROW(Error(getIndex(), "Failed to initialize signing context with " +
50  boost::lexical_cast<std::string>(algo) + " digest and " +
51  boost::lexical_cast<std::string>(key.getKeyType()) + " key"));
52 }
53 
54 SignerFilter::~SignerFilter() = default;
55 
56 size_t
57 SignerFilter::convert(span<const uint8_t> buf)
58 {
59  if (EVP_DigestSignUpdate(m_impl->ctx, buf.data(), buf.size()) != 1)
60  NDN_THROW(Error(getIndex(), "Failed to accept more input"));
61 
62  return buf.size();
63 }
64 
65 void
66 SignerFilter::finalize()
67 {
68  size_t sigLen = 0;
69  if (EVP_DigestSignFinal(m_impl->ctx, nullptr, &sigLen) != 1)
70  NDN_THROW(Error(getIndex(), "Failed to estimate buffer length"));
71 
72  auto buffer = make_unique<OBuffer>(sigLen);
73  if (EVP_DigestSignFinal(m_impl->ctx, buffer->data(), &sigLen) != 1)
74  NDN_THROW(Error(getIndex(), "Failed to finalize signature"));
75 
76  buffer->erase(buffer->begin() + sigLen, buffer->end());
77  setOutputBuffer(std::move(buffer));
78 
80 }
81 
82 unique_ptr<Transform>
84 {
85  return make_unique<SignerFilter>(algo, key);
86 }
87 
88 } // namespace transform
89 } // namespace security
90 } // namespace ndn
size_t getIndex() const
Get the module index.
Base class of transformation error.
Abstraction of private key in crypto transformation.
Definition: private-key.hpp:39
KeyType getKeyType() const
Returns the type of the private key.
Definition: private-key.cpp:81
SignerFilter(DigestAlgorithm algo, const PrivateKey &key)
Create a module to sign using digest algorithm algo and private key key.
void setOutputBuffer(unique_ptr< OBuffer > buffer)
Set output buffer to buffer.
void flushAllOutput()
Read the all the content from output buffer and write it into next module.
#define NDN_THROW(e)
Definition: exception.hpp:61
unique_ptr< Transform > signerFilter(DigestAlgorithm algo, const PrivateKey &key)
Definition: data.cpp:25