Support generation of EC keys using P256 curve and support ECDSA certs.

webrtc/base/opensslidentity.cc

Index: webrtc/base/opensslidentity.cc
diff --git a/webrtc/base/opensslidentity.cc b/webrtc/base/opensslidentity.cc
index dbb040ecf41d6ceaf7ca64f5ead6b000a40612f8..de4e6a771e04f5f0c1924ba83313f790a16988a2 100644
--- a/webrtc/base/opensslidentity.cc
+++ b/webrtc/base/opensslidentity.cc
@@ -46,23 +46,40 @@ static const int CERTIFICATE_LIFETIME = 60*60*24*30;  // 30 days, arbitrarily
 static const int CERTIFICATE_WINDOW = -60*60*24;
 
 // Generate a key pair. Caller is responsible for freeing the returned object.
-static EVP_PKEY* MakeKey() {
+static EVP_PKEY* MakeKey(KeyType key_type) {
   LOG(LS_INFO) << "Making key pair";
   EVP_PKEY* pkey = EVP_PKEY_new();
-  // RSA_generate_key is deprecated. Use _ex version.
-  BIGNUM* exponent = BN_new();
-  RSA* rsa = RSA_new();
-  if (!pkey || !exponent || !rsa ||
-      !BN_set_word(exponent, 0x10001) ||  // 65537 RSA exponent
-      !RSA_generate_key_ex(rsa, KEY_LENGTH, exponent, NULL) ||
-      !EVP_PKEY_assign_RSA(pkey, rsa)) {
-    EVP_PKEY_free(pkey);
+  if (key_type == KT_RSA) {
+    BIGNUM* exponent = BN_new();
+    RSA* rsa = RSA_new();
+    if (!pkey || !exponent || !rsa ||
+        !BN_set_word(exponent, 0x10001) ||  // 65537 RSA exponent
+        !RSA_generate_key_ex(rsa, KEY_LENGTH, exponent, NULL) ||
+        !EVP_PKEY_assign_RSA(pkey, rsa)) {
+      EVP_PKEY_free(pkey);
+      BN_free(exponent);
+      RSA_free(rsa);
+      LOG(LS_ERROR) << "Failed to make RSA key pair";
+      return NULL;
+    }
+    // ownership of rsa struct was assigned, don't free it.
     BN_free(exponent);
-    RSA_free(rsa);
+  } else if (key_type == KT_ECDSA) {
+    EC_KEY* ec_key = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
+    if (!pkey || !ec_key || !EC_KEY_generate_key(ec_key) ||
+        !EVP_PKEY_assign_EC_KEY(pkey, ec_key)) {
+      EVP_PKEY_free(pkey);
+      EC_KEY_free(ec_key);
+      LOG(LS_ERROR) << "Failed to make EC key pair";
+      return NULL;
+    }
+    // ownership of ec_key struct was assigned, don't free it.
+  } else {
+    EVP_PKEY_free(pkey);
+    LOG(LS_ERROR) << "Key type requested not understood";
     return NULL;
   }
-  // ownership of rsa struct was assigned, don't free it.
-  BN_free(exponent);
+
   LOG(LS_INFO) << "Returning key pair";
   return pkey;
 }
@@ -138,8 +155,8 @@ static void LogSSLErrors(const std::string& prefix) {
   }
 }
 
-OpenSSLKeyPair* OpenSSLKeyPair::Generate() {
-  EVP_PKEY* pkey = MakeKey();
+OpenSSLKeyPair* OpenSSLKeyPair::Generate(KeyType key_type) {
+  EVP_PKEY* pkey = MakeKey(key_type);
   if (!pkey) {
     LogSSLErrors("Generating key pair");
     return NULL;
@@ -207,8 +224,7 @@ OpenSSLCertificate* OpenSSLCertificate::FromPEMString(
   if (!bio)
     return NULL;
   BIO_set_mem_eof_return(bio, 0);
-  X509 *x509 = PEM_read_bio_X509(bio, NULL, NULL,
-                                 const_cast<char*>("\0"));
+  X509* x509 = PEM_read_bio_X509(bio, NULL, NULL, const_cast<char*>("\0"));
   BIO_free(bio);  // Frees the BIO, but not the pointed-to string.
 
   if (!x509)
@@ -283,7 +299,7 @@ bool OpenSSLCertificate::ComputeDigest(const X509* x509,
                                        unsigned char* digest,
                                        size_t size,
                                        size_t* length) {
-  const EVP_MD *md;
+  const EVP_MD* md;
   unsigned int n;
 
   if (!OpenSSLDigest::GetDigestEVP(algorithm, &md))
@@ -363,10 +379,10 @@ OpenSSLIdentity::~OpenSSLIdentity() = default;
 
 OpenSSLIdentity* OpenSSLIdentity::GenerateInternal(
     const SSLIdentityParams& params) {
-  OpenSSLKeyPair *key_pair = OpenSSLKeyPair::Generate();
+  OpenSSLKeyPair* key_pair = OpenSSLKeyPair::Generate(params.key_type);
   if (key_pair) {
-    OpenSSLCertificate *certificate = OpenSSLCertificate::Generate(
-        key_pair, params);
+    OpenSSLCertificate* certificate =
+        OpenSSLCertificate::Generate(key_pair, params);
     if (certificate)
       return new OpenSSLIdentity(key_pair, certificate);
     delete key_pair;
@@ -375,11 +391,13 @@ OpenSSLIdentity* OpenSSLIdentity::GenerateInternal(
   return NULL;
 }
 
-OpenSSLIdentity* OpenSSLIdentity::Generate(const std::string& common_name) {
+OpenSSLIdentity* OpenSSLIdentity::Generate(const std::string& common_name,
+                                           KeyType key_type) {
   SSLIdentityParams params;
   params.common_name = common_name;
   params.not_before = CERTIFICATE_WINDOW;
   params.not_after = CERTIFICATE_LIFETIME;
+  params.key_type = key_type;
   return GenerateInternal(params);
 }
 
@@ -404,8 +422,8 @@ SSLIdentity* OpenSSLIdentity::FromPEMStrings(
     return NULL;
   }
   BIO_set_mem_eof_return(bio, 0);
-  EVP_PKEY *pkey = PEM_read_bio_PrivateKey(bio, NULL, NULL,
-                                           const_cast<char*>("\0"));
+  EVP_PKEY* pkey =
+      PEM_read_bio_PrivateKey(bio, NULL, NULL, const_cast<char*>("\0"));
   BIO_free(bio);  // Frees the BIO, but not the pointed-to string.
 
   if (!pkey) {