From b2bea751aa3458e6cd2825cc2fa953c0d3157c7c Mon Sep 17 00:00:00 2001
From: csoler <retroshare.project@gmail.com>
Date: Sat, 7 Dec 2013 14:29:46 +0000
Subject: [PATCH] restriction to only accept self-signed certificates for
 friend keys

git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@6928 b45a01b8-16f6-495d-af2f-9b41ad6348cc
---
 libretroshare/src/pgp/pgphandler.cc           | 43 ++++++++++++++++++-
 .../src/tests/pgp/test_certificate.cc         |  6 +--
 2 files changed, 43 insertions(+), 6 deletions(-)

diff --git a/libretroshare/src/pgp/pgphandler.cc b/libretroshare/src/pgp/pgphandler.cc
index 6f9b0eaf1..d3cc9071c 100644
--- a/libretroshare/src/pgp/pgphandler.cc
+++ b/libretroshare/src/pgp/pgphandler.cc
@@ -954,12 +954,51 @@ bool PGPHandler::LoadCertificateFromString(const std::string& pgp_cert,PGPIdType
 	free(mem) ;
 	error_string.clear() ;
 
+	// Check that there is exactly one key in this data packet.
+	//
+	if(tmp_keyring->nkeys != 1)
+	{
+		std::cerr << "Loaded certificate contains more than one PGP key. This is not allowed." << std::endl;
+		error_string = "Loaded certificate contains more than one PGP key. This is not allowed." ;
+		return false ;
+	}
+
+	// Check that the key is correctly self-signed.
+	//
+	const ops_keydata_t *keydata = ops_keyring_get_key_by_index(tmp_keyring,0);
+
+	ops_validate_result_t* result=(ops_validate_result_t*)ops_mallocz(sizeof *result);
+
+	if(!ops_validate_key_signatures(result,keydata,tmp_keyring,cb_get_passphrase)) 
+	{
+		std::cerr << "Cannot validate self-signature for this certificate. Format error?" << std::endl;
+		error_string = "Cannot validate self signature for this certificate. Format error?" ;
+		return false ;
+	}
+
+	bool found = false ;
+
+	for(uint32_t i=0;i<result->valid_count;++i)
+		if(!memcmp((unsigned char*)result->valid_sigs[i].signer_id,keydata->key_id,KEY_ID_SIZE)) 
+		{
+			found = true ;
+			break ;
+		}
+
+	if(!found)
+	{
+		error_string = "This key is not self-signed. This is required by Retroshare." ;
+		std::cerr <<   "This key is not self-signed. This is required by Retroshare." << std::endl;
+		ops_validate_result_free(result);
+		return false ;
+	}
+	ops_validate_result_free(result);
+
 #ifdef DEBUG_PGPHANDLER
 	std::cerr << "  Key read correctly: " << std::endl;
-#endif
 	ops_keyring_list(tmp_keyring) ;
+#endif
 
-	const ops_keydata_t *keydata = NULL ;
 	int i=0 ;
 
 	while( (keydata = ops_keyring_get_key_by_index(tmp_keyring,i++)) != NULL )
diff --git a/libretroshare/src/tests/pgp/test_certificate.cc b/libretroshare/src/tests/pgp/test_certificate.cc
index b27c34de1..6659ea86a 100644
--- a/libretroshare/src/tests/pgp/test_certificate.cc
+++ b/libretroshare/src/tests/pgp/test_certificate.cc
@@ -85,6 +85,7 @@ int main(int argc,char *argv[])
 		std::string name ;
 		std::list<std::string> signers ;
 
+		PGPHandler::setPassphraseCallback(pgp_pwd_cb) ;
 		PGPHandler handler("toto1","toto2","toto3","toto4") ;
 		handler.getGPGDetailsFromBinaryBlock(cert.pgp_key(),cert.pgp_key_size(),key_id,name,signers) ;
 
@@ -114,10 +115,7 @@ int main(int argc,char *argv[])
 		std::string error_string ;
 		PGPIdType found_id ;
 
-		PGPHandler::setPassphraseCallback(pgp_pwd_cb) ;
-		PGPHandler pgph("pubring.pgp","secring.pgp","trustdb.pgp","lock") ;
-
-		bool result = pgph.LoadCertificateFromString(res,found_id,error_string) ;
+		bool result = handler.LoadCertificateFromString(res,found_id,error_string) ;
 
 		if(!result)
 			std::cerr << "Certificate error: " << error_string << std::endl;