Adds a modified copy of talk/base to webrtc/base. It is the first step in migrating talk/base to webrtc/base.

BUG=N/A
R=andrew@webrtc.org, wu@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/12199004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6107 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/base/sslidentity.h

@@ -0,0 +1,172 @@
+/*
+ *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// Handling of certificates and keypairs for SSLStreamAdapter's peer mode.
+
+#ifndef WEBRTC_BASE_SSLIDENTITY_H_
+#define WEBRTC_BASE_SSLIDENTITY_H_
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+#include "webrtc/base/buffer.h"
+#include "webrtc/base/messagedigest.h"
+
+namespace rtc {
+
+// Forward declaration due to circular dependency with SSLCertificate.
+class SSLCertChain;
+
+// Abstract interface overridden by SSL library specific
+// implementations.
+
+// A somewhat opaque type used to encapsulate a certificate.
+// Wraps the SSL library's notion of a certificate, with reference counting.
+// The SSLCertificate object is pretty much immutable once created.
+// (The OpenSSL implementation only does reference counting and
+// possibly caching of intermediate results.)
+class SSLCertificate {
+ public:
+  // Parses and build a certificate from a PEM encoded string.
+  // Returns NULL on failure.
+  // The length of the string representation of the certificate is
+  // stored in *pem_length if it is non-NULL, and only if
+  // parsing was successful.
+  // Caller is responsible for freeing the returned object.
+  static SSLCertificate* FromPEMString(const std::string& pem_string);
+  virtual ~SSLCertificate() {}
+
+  // Returns a new SSLCertificate object instance wrapping the same
+  // underlying certificate, including its chain if present.
+  // Caller is responsible for freeing the returned object.
+  virtual SSLCertificate* GetReference() const = 0;
+
+  // Provides the cert chain, or returns false.  The caller owns the chain.
+  // The chain includes a copy of each certificate, excluding the leaf.
+  virtual bool GetChain(SSLCertChain** chain) const = 0;
+
+  // Returns a PEM encoded string representation of the certificate.
+  virtual std::string ToPEMString() const = 0;
+
+  // Provides a DER encoded binary representation of the certificate.
+  virtual void ToDER(Buffer* der_buffer) const = 0;
+
+  // Gets the name of the digest algorithm that was used to compute this
+  // certificate's signature.
+  virtual bool GetSignatureDigestAlgorithm(std::string* algorithm) const = 0;
+
+  // Compute the digest of the certificate given algorithm
+  virtual bool ComputeDigest(const std::string& algorithm,
+                             unsigned char* digest,
+                             size_t size,
+                             size_t* length) const = 0;
+};
+
+// SSLCertChain is a simple wrapper for a vector of SSLCertificates. It serves
+// primarily to ensure proper memory management (especially deletion) of the
+// SSLCertificate pointers.
+class SSLCertChain {
+ public:
+  // These constructors copy the provided SSLCertificate(s), so the caller
+  // retains ownership.
+  explicit SSLCertChain(const std::vector<SSLCertificate*>& certs) {
+    ASSERT(!certs.empty());
+    certs_.resize(certs.size());
+    std::transform(certs.begin(), certs.end(), certs_.begin(), DupCert);
+  }
+  explicit SSLCertChain(const SSLCertificate* cert) {
+    certs_.push_back(cert->GetReference());
+  }
+
+  ~SSLCertChain() {
+    std::for_each(certs_.begin(), certs_.end(), DeleteCert);
+  }
+
+  // Vector access methods.
+  size_t GetSize() const { return certs_.size(); }
+
+  // Returns a temporary reference, only valid until the chain is destroyed.
+  const SSLCertificate& Get(size_t pos) const { return *(certs_[pos]); }
+
+  // Returns a new SSLCertChain object instance wrapping the same underlying
+  // certificate chain.  Caller is responsible for freeing the returned object.
+  SSLCertChain* Copy() const {
+    return new SSLCertChain(certs_);
+  }
+
+ private:
+  // Helper function for duplicating a vector of certificates.
+  static SSLCertificate* DupCert(const SSLCertificate* cert) {
+    return cert->GetReference();
+  }
+
+  // Helper function for deleting a vector of certificates.
+  static void DeleteCert(SSLCertificate* cert) { delete cert; }
+
+  std::vector<SSLCertificate*> certs_;
+
+  DISALLOW_COPY_AND_ASSIGN(SSLCertChain);
+};
+
+// Parameters for generating an identity for testing. If common_name is
+// non-empty, it will be used for the certificate's subject and issuer name,
+// otherwise a random string will be used. |not_before| and |not_after| are
+// offsets to the current time in number of seconds.
+struct SSLIdentityParams {
+  std::string common_name;
+  int not_before;  // in seconds.
+  int not_after;  // in seconds.
+};
+
+// Our identity in an SSL negotiation: a keypair and certificate (both
+// with the same public key).
+// This too is pretty much immutable once created.
+class SSLIdentity {
+ public:
+  // Generates an identity (keypair and self-signed certificate). If
+  // common_name is non-empty, it will be used for the certificate's
+  // subject and issuer name, otherwise a random string will be used.
+  // Returns NULL on failure.
+  // Caller is responsible for freeing the returned object.
+  static SSLIdentity* Generate(const std::string& common_name);
+
+  // Generates an identity with the specified validity period.
+  static SSLIdentity* GenerateForTest(const SSLIdentityParams& params);
+
+  // Construct an identity from a private key and a certificate.
+  static SSLIdentity* FromPEMStrings(const std::string& private_key,
+                                     const std::string& certificate);
+
+  virtual ~SSLIdentity() {}
+
+  // Returns a new SSLIdentity object instance wrapping the same
+  // identity information.
+  // Caller is responsible for freeing the returned object.
+  virtual SSLIdentity* GetReference() const = 0;
+
+  // Returns a temporary reference to the certificate.
+  virtual const SSLCertificate& certificate() const = 0;
+
+  // Helpers for parsing converting between PEM and DER format.
+  static bool PemToDer(const std::string& pem_type,
+                       const std::string& pem_string,
+                       std::string* der);
+  static std::string DerToPem(const std::string& pem_type,
+                              const unsigned char* data,
+                              size_t length);
+};
+
+extern const char kPemTypeCertificate[];
+extern const char kPemTypeRsaPrivateKey[];
+
+}  // namespace rtc
+
+#endif  // WEBRTC_BASE_SSLIDENTITY_H_