michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsDataSignatureVerifier.h"
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsString.h"
michael@0: 
michael@0: #include "seccomon.h"
michael@0: #include "nssb64.h"
michael@0: #include "certt.h"
michael@0: #include "keyhi.h"
michael@0: #include "cryptohi.h"
michael@0: 
michael@0: SEC_ASN1_MKSUB(SECOID_AlgorithmIDTemplate)
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(nsDataSignatureVerifier, nsIDataSignatureVerifier)
michael@0: 
michael@0: const SEC_ASN1Template CERT_SignatureDataTemplate[] =
michael@0: {
michael@0:     { SEC_ASN1_SEQUENCE,
michael@0:         0, nullptr, sizeof(CERTSignedData) },
michael@0:     { SEC_ASN1_INLINE | SEC_ASN1_XTRN,
michael@0:         offsetof(CERTSignedData,signatureAlgorithm),
michael@0:         SEC_ASN1_SUB(SECOID_AlgorithmIDTemplate), },
michael@0:     { SEC_ASN1_BIT_STRING,
michael@0:         offsetof(CERTSignedData,signature), },
michael@0:     { 0, }
michael@0: };
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsDataSignatureVerifier::VerifyData(const nsACString & aData,
michael@0:                                     const nsACString & aSignature,
michael@0:                                     const nsACString & aPublicKey,
michael@0:                                     bool *_retval)
michael@0: {
michael@0:     // Allocate an arena to handle the majority of the allocations
michael@0:     PLArenaPool *arena;
michael@0:     arena = PORT_NewArena(DER_DEFAULT_CHUNKSIZE);
michael@0:     if (!arena)
michael@0:         return NS_ERROR_OUT_OF_MEMORY;
michael@0: 
michael@0:     // Base 64 decode the key
michael@0:     SECItem keyItem;
michael@0:     PORT_Memset(&keyItem, 0, sizeof(SECItem));
michael@0:     if (!NSSBase64_DecodeBuffer(arena, &keyItem,
michael@0:                                 nsPromiseFlatCString(aPublicKey).get(),
michael@0:                                 aPublicKey.Length())) {
michael@0:         PORT_FreeArena(arena, false);
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0:     
michael@0:     // Extract the public key from the data
michael@0:     CERTSubjectPublicKeyInfo *pki = SECKEY_DecodeDERSubjectPublicKeyInfo(&keyItem);
michael@0:     if (!pki) {
michael@0:         PORT_FreeArena(arena, false);
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0:     SECKEYPublicKey *publicKey = SECKEY_ExtractPublicKey(pki);
michael@0:     SECKEY_DestroySubjectPublicKeyInfo(pki);
michael@0:     pki = nullptr;
michael@0:     
michael@0:     if (!publicKey) {
michael@0:         PORT_FreeArena(arena, false);
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0:     
michael@0:     // Base 64 decode the signature
michael@0:     SECItem signatureItem;
michael@0:     PORT_Memset(&signatureItem, 0, sizeof(SECItem));
michael@0:     if (!NSSBase64_DecodeBuffer(arena, &signatureItem,
michael@0:                                 nsPromiseFlatCString(aSignature).get(),
michael@0:                                 aSignature.Length())) {
michael@0:         SECKEY_DestroyPublicKey(publicKey);
michael@0:         PORT_FreeArena(arena, false);
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0:     
michael@0:     // Decode the signature and algorithm
michael@0:     CERTSignedData sigData;
michael@0:     PORT_Memset(&sigData, 0, sizeof(CERTSignedData));
michael@0:     SECStatus ss = SEC_QuickDERDecodeItem(arena, &sigData, 
michael@0:                                           CERT_SignatureDataTemplate,
michael@0:                                           &signatureItem);
michael@0:     if (ss != SECSuccess) {
michael@0:         SECKEY_DestroyPublicKey(publicKey);
michael@0:         PORT_FreeArena(arena, false);
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0:     
michael@0:     // Perform the final verification
michael@0:     DER_ConvertBitString(&(sigData.signature));
michael@0:     ss = VFY_VerifyDataWithAlgorithmID((const unsigned char*)nsPromiseFlatCString(aData).get(),
michael@0:                                        aData.Length(), publicKey,
michael@0:                                        &(sigData.signature),
michael@0:                                        &(sigData.signatureAlgorithm),
michael@0:                                        nullptr, nullptr);
michael@0:     
michael@0:     // Clean up remaining objects
michael@0:     SECKEY_DestroyPublicKey(publicKey);
michael@0:     PORT_FreeArena(arena, false);
michael@0:     
michael@0:     *_retval = (ss == SECSuccess);
michael@0: 
michael@0:     return NS_OK;
michael@0: }