The Tor Browser / file diff

     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/security/manager/ssl/src/nsDataSignatureVerifier.cpp	Wed Dec 31 06:09:35 2014 +0100
     1.3 @@ -0,0 +1,106 @@
     1.4 +/* This Source Code Form is subject to the terms of the Mozilla Public
     1.5 + * License, v. 2.0. If a copy of the MPL was not distributed with this
     1.6 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
     1.7 +
     1.8 +#include "nsDataSignatureVerifier.h"
     1.9 +#include "nsCOMPtr.h"
    1.10 +#include "nsString.h"
    1.11 +
    1.12 +#include "seccomon.h"
    1.13 +#include "nssb64.h"
    1.14 +#include "certt.h"
    1.15 +#include "keyhi.h"
    1.16 +#include "cryptohi.h"
    1.17 +
    1.18 +SEC_ASN1_MKSUB(SECOID_AlgorithmIDTemplate)
    1.19 +
    1.20 +NS_IMPL_ISUPPORTS(nsDataSignatureVerifier, nsIDataSignatureVerifier)
    1.21 +
    1.22 +const SEC_ASN1Template CERT_SignatureDataTemplate[] =
    1.23 +{
    1.24 +    { SEC_ASN1_SEQUENCE,
    1.25 +        0, nullptr, sizeof(CERTSignedData) },
    1.26 +    { SEC_ASN1_INLINE | SEC_ASN1_XTRN,
    1.27 +        offsetof(CERTSignedData,signatureAlgorithm),
    1.28 +        SEC_ASN1_SUB(SECOID_AlgorithmIDTemplate), },
    1.29 +    { SEC_ASN1_BIT_STRING,
    1.30 +        offsetof(CERTSignedData,signature), },
    1.31 +    { 0, }
    1.32 +};
    1.33 +
    1.34 +NS_IMETHODIMP
    1.35 +nsDataSignatureVerifier::VerifyData(const nsACString & aData,
    1.36 +                                    const nsACString & aSignature,
    1.37 +                                    const nsACString & aPublicKey,
    1.38 +                                    bool *_retval)
    1.39 +{
    1.40 +    // Allocate an arena to handle the majority of the allocations
    1.41 +    PLArenaPool *arena;
    1.42 +    arena = PORT_NewArena(DER_DEFAULT_CHUNKSIZE);
    1.43 +    if (!arena)
    1.44 +        return NS_ERROR_OUT_OF_MEMORY;
    1.45 +
    1.46 +    // Base 64 decode the key
    1.47 +    SECItem keyItem;
    1.48 +    PORT_Memset(&keyItem, 0, sizeof(SECItem));
    1.49 +    if (!NSSBase64_DecodeBuffer(arena, &keyItem,
    1.50 +                                nsPromiseFlatCString(aPublicKey).get(),
    1.51 +                                aPublicKey.Length())) {
    1.52 +        PORT_FreeArena(arena, false);
    1.53 +        return NS_ERROR_FAILURE;
    1.54 +    }
    1.55 +    
    1.56 +    // Extract the public key from the data
    1.57 +    CERTSubjectPublicKeyInfo *pki = SECKEY_DecodeDERSubjectPublicKeyInfo(&keyItem);
    1.58 +    if (!pki) {
    1.59 +        PORT_FreeArena(arena, false);
    1.60 +        return NS_ERROR_FAILURE;
    1.61 +    }
    1.62 +    SECKEYPublicKey *publicKey = SECKEY_ExtractPublicKey(pki);
    1.63 +    SECKEY_DestroySubjectPublicKeyInfo(pki);
    1.64 +    pki = nullptr;
    1.65 +    
    1.66 +    if (!publicKey) {
    1.67 +        PORT_FreeArena(arena, false);
    1.68 +        return NS_ERROR_FAILURE;
    1.69 +    }
    1.70 +    
    1.71 +    // Base 64 decode the signature
    1.72 +    SECItem signatureItem;
    1.73 +    PORT_Memset(&signatureItem, 0, sizeof(SECItem));
    1.74 +    if (!NSSBase64_DecodeBuffer(arena, &signatureItem,
    1.75 +                                nsPromiseFlatCString(aSignature).get(),
    1.76 +                                aSignature.Length())) {
    1.77 +        SECKEY_DestroyPublicKey(publicKey);
    1.78 +        PORT_FreeArena(arena, false);
    1.79 +        return NS_ERROR_FAILURE;
    1.80 +    }
    1.81 +    
    1.82 +    // Decode the signature and algorithm
    1.83 +    CERTSignedData sigData;
    1.84 +    PORT_Memset(&sigData, 0, sizeof(CERTSignedData));
    1.85 +    SECStatus ss = SEC_QuickDERDecodeItem(arena, &sigData, 
    1.86 +                                          CERT_SignatureDataTemplate,
    1.87 +                                          &signatureItem);
    1.88 +    if (ss != SECSuccess) {
    1.89 +        SECKEY_DestroyPublicKey(publicKey);
    1.90 +        PORT_FreeArena(arena, false);
    1.91 +        return NS_ERROR_FAILURE;
    1.92 +    }
    1.93 +    
    1.94 +    // Perform the final verification
    1.95 +    DER_ConvertBitString(&(sigData.signature));
    1.96 +    ss = VFY_VerifyDataWithAlgorithmID((const unsigned char*)nsPromiseFlatCString(aData).get(),
    1.97 +                                       aData.Length(), publicKey,
    1.98 +                                       &(sigData.signature),
    1.99 +                                       &(sigData.signatureAlgorithm),
   1.100 +                                       nullptr, nullptr);
   1.101 +    
   1.102 +    // Clean up remaining objects
   1.103 +    SECKEY_DestroyPublicKey(publicKey);
   1.104 +    PORT_FreeArena(arena, false);
   1.105 +    
   1.106 +    *_retval = (ss == SECSuccess);
   1.107 +
   1.108 +    return NS_OK;
   1.109 +}