Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 952 insertions, 0 deletions

diff --git a/security/nss/lib/cryptohi/secvfy.c b/security/nss/lib/cryptohi/secvfy.c
new file mode 100644
index 0000000000..8c9dc2d87d
--- /dev/null
+++ b/security/nss/lib/cryptohi/secvfy.c
@@ -0,0 +1,952 @@
+/*
+ * Verification stuff.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <stdio.h>
+#include "cryptohi.h"
+#include "sechash.h"
+#include "keyhi.h"
+#include "secasn1.h"
+#include "secoid.h"
+#include "pk11func.h"
+#include "pkcs1sig.h"
+#include "secdig.h"
+#include "secerr.h"
+#include "keyi.h"
+#include "nss.h"
+
+/*
+** Recover the DigestInfo from an RSA PKCS#1 signature.
+**
+** If givenDigestAlg != SEC_OID_UNKNOWN, copy givenDigestAlg to digestAlgOut.
+** Otherwise, parse the DigestInfo structure and store the decoded digest
+** algorithm into digestAlgOut.
+**
+** Store the encoded DigestInfo into digestInfo.
+** Store the DigestInfo length into digestInfoLen.
+**
+** This function does *not* verify that the AlgorithmIdentifier in the
+** DigestInfo identifies givenDigestAlg or that the DigestInfo is encoded
+** correctly; verifyPKCS1DigestInfo does that.
+**
+** XXX this is assuming that the signature algorithm has WITH_RSA_ENCRYPTION
+*/
+static SECStatus
+recoverPKCS1DigestInfo(SECOidTag givenDigestAlg,
+                       /*out*/ SECOidTag *digestAlgOut,
+                       /*out*/ unsigned char **digestInfo,
+                       /*out*/ unsigned int *digestInfoLen,
+                       SECKEYPublicKey *key,
+                       const SECItem *sig, void *wincx)
+{
+    SGNDigestInfo *di = NULL;
+    SECItem it;
+    PRBool rv = SECSuccess;
+
+    PORT_Assert(digestAlgOut);
+    PORT_Assert(digestInfo);
+    PORT_Assert(digestInfoLen);
+    PORT_Assert(key);
+    PORT_Assert(key->keyType == rsaKey);
+    PORT_Assert(sig);
+
+    it.data = NULL;
+    it.len = SECKEY_PublicKeyStrength(key);
+    if (it.len != 0) {
+        it.data = (unsigned char *)PORT_Alloc(it.len);
+    }
+    if (it.len == 0 || it.data == NULL) {
+        rv = SECFailure;
+    }
+
+    if (rv == SECSuccess) {
+        /* decrypt the block */
+        rv = PK11_VerifyRecover(key, sig, &it, wincx);
+    }
+
+    if (rv == SECSuccess) {
+        if (givenDigestAlg != SEC_OID_UNKNOWN) {
+            /* We don't need to parse the DigestInfo if the caller gave us the
+             * digest algorithm to use. Later verifyPKCS1DigestInfo will verify
+             * that the DigestInfo identifies the given digest algorithm and
+             * that the DigestInfo is encoded absolutely correctly.
+             */
+            *digestInfoLen = it.len;
+            *digestInfo = (unsigned char *)it.data;
+            *digestAlgOut = givenDigestAlg;
+            return SECSuccess;
+        }
+    }
+
+    if (rv == SECSuccess) {
+        /* The caller didn't specify a digest algorithm to use, so choose the
+         * digest algorithm by parsing the AlgorithmIdentifier within the
+         * DigestInfo.
+         */
+        di = SGN_DecodeDigestInfo(&it);
+        if (!di) {
+            rv = SECFailure;
+        }
+    }
+
+    if (rv == SECSuccess) {
+        *digestAlgOut = SECOID_GetAlgorithmTag(&di->digestAlgorithm);
+        if (*digestAlgOut == SEC_OID_UNKNOWN) {
+            rv = SECFailure;
+        }
+    }
+
+    if (di) {
+        SGN_DestroyDigestInfo(di);
+    }
+
+    if (rv == SECSuccess) {
+        *digestInfoLen = it.len;
+        *digestInfo = (unsigned char *)it.data;
+    } else {
+        if (it.data) {
+            PORT_Free(it.data);
+        }
+        *digestInfo = NULL;
+        *digestInfoLen = 0;
+        PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+    }
+
+    return rv;
+}
+
+struct VFYContextStr {
+    SECOidTag hashAlg; /* the hash algorithm */
+    SECKEYPublicKey *key;
+    /*
+     * This buffer holds either the digest or the full signature
+     * depending on the type of the signature (key->keyType).  It is
+     * defined as a union to make sure it always has enough space.
+     *
+     * Use the "buffer" union member to reference the buffer.
+     * Note: do not take the size of the "buffer" union member.  Take
+     * the size of the union or some other union member instead.
+     */
+    union {
+        unsigned char buffer[1];
+
+        /* the full DSA signature... 40 bytes */
+        unsigned char dsasig[DSA_MAX_SIGNATURE_LEN];
+        /* the full ECDSA signature */
+        unsigned char ecdsasig[2 * MAX_ECKEY_LEN];
+        /* the full RSA signature, only used in RSA-PSS */
+        unsigned char rsasig[(RSA_MAX_MODULUS_BITS + 7) / 8];
+    } u;
+    unsigned int pkcs1RSADigestInfoLen;
+    /* the encoded DigestInfo from a RSA PKCS#1 signature */
+    unsigned char *pkcs1RSADigestInfo;
+    void *wincx;
+    void *hashcx;
+    const SECHashObject *hashobj;
+    SECOidTag encAlg;    /* enc alg */
+    PRBool hasSignature; /* true if the signature was provided in the
+                          * VFY_CreateContext call.  If false, the
+                          * signature must be provided with a
+                          * VFY_EndWithSignature call. */
+    SECItem *params;
+};
+
+static SECStatus
+verifyPKCS1DigestInfo(const VFYContext *cx, const SECItem *digest)
+{
+    SECItem pkcs1DigestInfo;
+    pkcs1DigestInfo.data = cx->pkcs1RSADigestInfo;
+    pkcs1DigestInfo.len = cx->pkcs1RSADigestInfoLen;
+    return _SGN_VerifyPKCS1DigestInfo(
+        cx->hashAlg, digest, &pkcs1DigestInfo,
+        PR_FALSE /*XXX: unsafeAllowMissingParameters*/);
+}
+
+static unsigned int
+checkedSignatureLen(const SECKEYPublicKey *pubk)
+{
+    unsigned int sigLen = SECKEY_SignatureLen(pubk);
+    if (sigLen == 0) {
+        /* Error set by SECKEY_SignatureLen */
+        return sigLen;
+    }
+    unsigned int maxSigLen;
+    switch (pubk->keyType) {
+        case rsaKey:
+        case rsaPssKey:
+            maxSigLen = (RSA_MAX_MODULUS_BITS + 7) / 8;
+            break;
+        case dsaKey:
+            maxSigLen = DSA_MAX_SIGNATURE_LEN;
+            break;
+        case ecKey:
+            maxSigLen = 2 * MAX_ECKEY_LEN;
+            break;
+        default:
+            PORT_SetError(SEC_ERROR_UNSUPPORTED_KEYALG);
+            return 0;
+    }
+    if (sigLen > maxSigLen) {
+        PORT_SetError(SEC_ERROR_INVALID_KEY);
+        return 0;
+    }
+    return sigLen;
+}
+
+/*
+ * decode the ECDSA or DSA signature from it's DER wrapping.
+ * The unwrapped/raw signature is placed in the buffer pointed
+ * to by dsig and has enough room for len bytes.
+ */
+static SECStatus
+decodeECorDSASignature(SECOidTag algid, const SECItem *sig, unsigned char *dsig,
+                       unsigned int len)
+{
+    SECItem *dsasig = NULL; /* also used for ECDSA */
+
+    /* Safety: Ensure algId is as expected and that signature size is within maxmimums */
+    if (algid == SEC_OID_ANSIX9_DSA_SIGNATURE) {
+        if (len > DSA_MAX_SIGNATURE_LEN) {
+            goto loser;
+        }
+    } else if (algid == SEC_OID_ANSIX962_EC_PUBLIC_KEY) {
+        if (len > MAX_ECKEY_LEN * 2) {
+            goto loser;
+        }
+    } else {
+        goto loser;
+    }
+
+    /* Decode and pad to length */
+    dsasig = DSAU_DecodeDerSigToLen((SECItem *)sig, len);
+    if (dsasig == NULL) {
+        goto loser;
+    }
+    if (dsasig->len != len) {
+        SECITEM_FreeItem(dsasig, PR_TRUE);
+        goto loser;
+    }
+
+    PORT_Memcpy(dsig, dsasig->data, len);
+    SECITEM_FreeItem(dsasig, PR_TRUE);
+
+    return SECSuccess;
+
+loser:
+    PORT_SetError(SEC_ERROR_BAD_DER);
+    return SECFailure;
+}
+
+const SEC_ASN1Template hashParameterTemplate[] = {
+    { SEC_ASN1_SEQUENCE, 0, NULL, sizeof(SECItem) },
+    { SEC_ASN1_OBJECT_ID, 0 },
+    { SEC_ASN1_SKIP_REST },
+    { 0 }
+};
+
+/*
+ * Get just the encryption algorithm from the signature algorithm
+ */
+SECOidTag
+sec_GetEncAlgFromSigAlg(SECOidTag sigAlg)
+{
+    /* get the "encryption" algorithm */
+    switch (sigAlg) {
+        case SEC_OID_PKCS1_RSA_ENCRYPTION:
+        case SEC_OID_PKCS1_MD2_WITH_RSA_ENCRYPTION:
+        case SEC_OID_PKCS1_MD5_WITH_RSA_ENCRYPTION:
+        case SEC_OID_PKCS1_SHA1_WITH_RSA_ENCRYPTION:
+        case SEC_OID_ISO_SHA_WITH_RSA_SIGNATURE:
+        case SEC_OID_ISO_SHA1_WITH_RSA_SIGNATURE:
+        case SEC_OID_PKCS1_SHA224_WITH_RSA_ENCRYPTION:
+        case SEC_OID_PKCS1_SHA256_WITH_RSA_ENCRYPTION:
+        case SEC_OID_PKCS1_SHA384_WITH_RSA_ENCRYPTION:
+        case SEC_OID_PKCS1_SHA512_WITH_RSA_ENCRYPTION:
+            return SEC_OID_PKCS1_RSA_ENCRYPTION;
+        case SEC_OID_PKCS1_RSA_PSS_SIGNATURE:
+            return SEC_OID_PKCS1_RSA_PSS_SIGNATURE;
+
+        /* what about normal DSA? */
+        case SEC_OID_ANSIX9_DSA_SIGNATURE_WITH_SHA1_DIGEST:
+        case SEC_OID_BOGUS_DSA_SIGNATURE_WITH_SHA1_DIGEST:
+        case SEC_OID_NIST_DSA_SIGNATURE_WITH_SHA224_DIGEST:
+        case SEC_OID_NIST_DSA_SIGNATURE_WITH_SHA256_DIGEST:
+            return SEC_OID_ANSIX9_DSA_SIGNATURE;
+        case SEC_OID_MISSI_DSS:
+        case SEC_OID_MISSI_KEA_DSS:
+        case SEC_OID_MISSI_KEA_DSS_OLD:
+        case SEC_OID_MISSI_DSS_OLD:
+            return SEC_OID_MISSI_DSS;
+        case SEC_OID_ANSIX962_ECDSA_SHA1_SIGNATURE:
+        case SEC_OID_ANSIX962_ECDSA_SHA224_SIGNATURE:
+        case SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE:
+        case SEC_OID_ANSIX962_ECDSA_SHA384_SIGNATURE:
+        case SEC_OID_ANSIX962_ECDSA_SHA512_SIGNATURE:
+        case SEC_OID_ANSIX962_ECDSA_SIGNATURE_RECOMMENDED_DIGEST:
+        case SEC_OID_ANSIX962_ECDSA_SIGNATURE_SPECIFIED_DIGEST:
+            return SEC_OID_ANSIX962_EC_PUBLIC_KEY;
+        /* we don't implement MD4 hashes */
+        case SEC_OID_PKCS1_MD4_WITH_RSA_ENCRYPTION:
+        default:
+            PORT_SetError(SEC_ERROR_INVALID_ALGORITHM);
+            break;
+    }
+    return SEC_OID_UNKNOWN;
+}
+
+/*
+ * Pulls the hash algorithm, signing algorithm, and key type out of a
+ * composite algorithm.
+ *
+ * sigAlg: the composite algorithm to dissect.
+ * hashalg: address of a SECOidTag which will be set with the hash algorithm.
+ * encalg: address of a SECOidTag which will be set with the signing alg.
+ *
+ * Returns: SECSuccess if the algorithm was acceptable, SECFailure if the
+ *	algorithm was not found or was not a signing algorithm.
+ */
+SECStatus
+sec_DecodeSigAlg(const SECKEYPublicKey *key, SECOidTag sigAlg,
+                 const SECItem *param, SECOidTag *encalgp, SECOidTag *hashalg)
+{
+    unsigned int len;
+    PLArenaPool *arena;
+    SECStatus rv;
+    SECItem oid;
+    SECOidTag encalg;
+
+    PR_ASSERT(hashalg != NULL);
+    PR_ASSERT(encalgp != NULL);
+
+    switch (sigAlg) {
+        /* We probably shouldn't be generating MD2 signatures either */
+        case SEC_OID_PKCS1_MD2_WITH_RSA_ENCRYPTION:
+            *hashalg = SEC_OID_MD2;
+            break;
+        case SEC_OID_PKCS1_MD5_WITH_RSA_ENCRYPTION:
+            *hashalg = SEC_OID_MD5;
+            break;
+        case SEC_OID_PKCS1_SHA1_WITH_RSA_ENCRYPTION:
+        case SEC_OID_ISO_SHA_WITH_RSA_SIGNATURE:
+        case SEC_OID_ISO_SHA1_WITH_RSA_SIGNATURE:
+            *hashalg = SEC_OID_SHA1;
+            break;
+        case SEC_OID_PKCS1_RSA_ENCRYPTION:
+            *hashalg = SEC_OID_UNKNOWN; /* get it from the RSA signature */
+            break;
+        case SEC_OID_PKCS1_RSA_PSS_SIGNATURE:
+            if (param && param->data) {
+                PORTCheapArenaPool tmpArena;
+
+                PORT_InitCheapArena(&tmpArena, DER_DEFAULT_CHUNKSIZE);
+                rv = sec_DecodeRSAPSSParams(&tmpArena.arena, param,
+                                            hashalg, NULL, NULL);
+                PORT_DestroyCheapArena(&tmpArena);
+
+                /* only accept hash algorithms */
+                if (rv != SECSuccess || HASH_GetHashTypeByOidTag(*hashalg) == HASH_AlgNULL) {
+                    /* error set by sec_DecodeRSAPSSParams or HASH_GetHashTypeByOidTag */
+                    return SECFailure;
+                }
+            } else {
+                *hashalg = SEC_OID_SHA1; /* default, SHA-1 */
+            }
+            break;
+
+        case SEC_OID_ANSIX962_ECDSA_SHA224_SIGNATURE:
+        case SEC_OID_PKCS1_SHA224_WITH_RSA_ENCRYPTION:
+        case SEC_OID_NIST_DSA_SIGNATURE_WITH_SHA224_DIGEST:
+            *hashalg = SEC_OID_SHA224;
+            break;
+        case SEC_OID_ANSIX962_ECDSA_SHA256_SIGNATURE:
+        case SEC_OID_PKCS1_SHA256_WITH_RSA_ENCRYPTION:
+        case SEC_OID_NIST_DSA_SIGNATURE_WITH_SHA256_DIGEST:
+            *hashalg = SEC_OID_SHA256;
+            break;
+        case SEC_OID_ANSIX962_ECDSA_SHA384_SIGNATURE:
+        case SEC_OID_PKCS1_SHA384_WITH_RSA_ENCRYPTION:
+            *hashalg = SEC_OID_SHA384;
+            break;
+        case SEC_OID_ANSIX962_ECDSA_SHA512_SIGNATURE:
+        case SEC_OID_PKCS1_SHA512_WITH_RSA_ENCRYPTION:
+            *hashalg = SEC_OID_SHA512;
+            break;
+
+        /* what about normal DSA? */
+        case SEC_OID_ANSIX9_DSA_SIGNATURE_WITH_SHA1_DIGEST:
+        case SEC_OID_BOGUS_DSA_SIGNATURE_WITH_SHA1_DIGEST:
+        case SEC_OID_ANSIX962_ECDSA_SHA1_SIGNATURE:
+            *hashalg = SEC_OID_SHA1;
+            break;
+        case SEC_OID_MISSI_DSS:
+        case SEC_OID_MISSI_KEA_DSS:
+        case SEC_OID_MISSI_KEA_DSS_OLD:
+        case SEC_OID_MISSI_DSS_OLD:
+            *hashalg = SEC_OID_SHA1;
+            break;
+        case SEC_OID_ANSIX962_ECDSA_SIGNATURE_RECOMMENDED_DIGEST:
+            /* This is an EC algorithm. Recommended means the largest
+             * hash algorithm that is not reduced by the keysize of
+             * the EC algorithm. Note that key strength is in bytes and
+             * algorithms are specified in bits. Never use an algorithm
+             * weaker than sha1. */
+            len = SECKEY_PublicKeyStrength(key);
+            if (len < 28) { /* 28 bytes == 224 bits */
+                *hashalg = SEC_OID_SHA1;
+            } else if (len < 32) { /* 32 bytes == 256 bits */
+                *hashalg = SEC_OID_SHA224;
+            } else if (len < 48) { /* 48 bytes == 384 bits */
+                *hashalg = SEC_OID_SHA256;
+            } else if (len < 64) { /* 48 bytes == 512 bits */
+                *hashalg = SEC_OID_SHA384;
+            } else {
+                /* use the largest in this case */
+                *hashalg = SEC_OID_SHA512;
+            }
+            break;
+        case SEC_OID_ANSIX962_ECDSA_SIGNATURE_SPECIFIED_DIGEST:
+            if (param == NULL) {
+                PORT_SetError(SEC_ERROR_INVALID_ALGORITHM);
+                return SECFailure;
+            }
+            arena = PORT_NewArena(DER_DEFAULT_CHUNKSIZE);
+            if (arena == NULL) {
+                return SECFailure;
+            }
+            rv = SEC_QuickDERDecodeItem(arena, &oid, hashParameterTemplate, param);
+            if (rv == SECSuccess) {
+                *hashalg = SECOID_FindOIDTag(&oid);
+            }
+            PORT_FreeArena(arena, PR_FALSE);
+            if (rv != SECSuccess) {
+                return rv;
+            }
+            /* only accept hash algorithms */
+            if (HASH_GetHashTypeByOidTag(*hashalg) == HASH_AlgNULL) {
+                /* error set by HASH_GetHashTypeByOidTag */
+                return SECFailure;
+            }
+            break;
+        /* we don't implement MD4 hashes */
+        case SEC_OID_PKCS1_MD4_WITH_RSA_ENCRYPTION:
+        default:
+            PORT_SetError(SEC_ERROR_INVALID_ALGORITHM);
+            return SECFailure;
+    }
+
+    encalg = sec_GetEncAlgFromSigAlg(sigAlg);
+    if (encalg == SEC_OID_UNKNOWN) {
+        return SECFailure;
+    }
+    *encalgp = encalg;
+
+    return SECSuccess;
+}
+
+/*
+ * we can verify signatures that come from 2 different sources:
+ *  one in with the signature contains a signature oid, and the other
+ *  in which the signature is managed by a Public key (encAlg) oid
+ *  and a hash oid. The latter is the more basic, so that's what
+ *  our base vfyCreate function takes.
+ *
+ * There is one noteworthy corner case, if we are using an RSA key, and the
+ * signature block is provided, then the hashAlg can be specified as
+ * SEC_OID_UNKNOWN. In this case, verify will use the hash oid supplied
+ * in the RSA signature block.
+ */
+static VFYContext *
+vfy_CreateContext(const SECKEYPublicKey *key, const SECItem *sig,
+                  SECOidTag encAlg, SECOidTag hashAlg, SECOidTag *hash, void *wincx)
+{
+    VFYContext *cx;
+    SECStatus rv;
+    unsigned int sigLen;
+    KeyType type;
+    PRUint32 policyFlags;
+    PRInt32 optFlags;
+
+    /* make sure the encryption algorithm matches the key type */
+    /* RSA-PSS algorithm can be used with both rsaKey and rsaPssKey */
+    type = seckey_GetKeyType(encAlg);
+    if ((key->keyType != type) &&
+        ((key->keyType != rsaKey) || (type != rsaPssKey))) {
+        PORT_SetError(SEC_ERROR_PKCS7_KEYALG_MISMATCH);
+        return NULL;
+    }
+    if (NSS_OptionGet(NSS_KEY_SIZE_POLICY_FLAGS, &optFlags) != SECFailure) {
+        if (optFlags & NSS_KEY_SIZE_POLICY_VERIFY_FLAG) {
+            rv = seckey_EnforceKeySize(key->keyType,
+                                       SECKEY_PublicKeyStrengthInBits(key),
+                                       SEC_ERROR_SIGNATURE_ALGORITHM_DISABLED);
+            if (rv != SECSuccess) {
+                return NULL;
+            }
+        }
+    }
+    /* check the policy on the encryption algorithm */
+    if ((NSS_GetAlgorithmPolicy(encAlg, &policyFlags) == SECFailure) ||
+        !(policyFlags & NSS_USE_ALG_IN_ANY_SIGNATURE)) {
+        PORT_SetError(SEC_ERROR_SIGNATURE_ALGORITHM_DISABLED);
+        return NULL;
+    }
+
+    cx = (VFYContext *)PORT_ZAlloc(sizeof(VFYContext));
+    if (cx == NULL) {
+        goto loser;
+    }
+
+    cx->wincx = wincx;
+    cx->hasSignature = (sig != NULL);
+    cx->encAlg = encAlg;
+    cx->hashAlg = hashAlg;
+    cx->key = SECKEY_CopyPublicKey(key);
+    cx->pkcs1RSADigestInfo = NULL;
+    rv = SECSuccess;
+    if (sig) {
+        rv = SECFailure;
+        if (type == rsaKey) {
+            rv = recoverPKCS1DigestInfo(hashAlg, &cx->hashAlg,
+                                        &cx->pkcs1RSADigestInfo,
+                                        &cx->pkcs1RSADigestInfoLen,
+                                        cx->key,
+                                        sig, wincx);
+        } else {
+            sigLen = checkedSignatureLen(key);
+            /* Check signature length is within limits */
+            if (sigLen == 0) {
+                /* error set by checkedSignatureLen */
+                rv = SECFailure;
+                goto loser;
+            }
+            if (sigLen > sizeof(cx->u)) {
+                PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                rv = SECFailure;
+                goto loser;
+            }
+            switch (type) {
+                case rsaPssKey:
+                    if (sig->len != sigLen) {
+                        PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                        rv = SECFailure;
+                        goto loser;
+                    }
+                    PORT_Memcpy(cx->u.buffer, sig->data, sigLen);
+                    rv = SECSuccess;
+                    break;
+                case ecKey:
+                case dsaKey:
+                    /* decodeECorDSASignature will check sigLen == sig->len after padding */
+                    rv = decodeECorDSASignature(encAlg, sig, cx->u.buffer, sigLen);
+                    break;
+                default:
+                    /* Unreachable */
+                    rv = SECFailure;
+                    goto loser;
+            }
+        }
+        if (rv != SECSuccess) {
+            goto loser;
+        }
+    }
+
+    /* check hash alg again, RSA may have changed it.*/
+    if (HASH_GetHashTypeByOidTag(cx->hashAlg) == HASH_AlgNULL) {
+        /* error set by HASH_GetHashTypeByOidTag */
+        goto loser;
+    }
+    /* check the policy on the hash algorithm. Do this after
+     * the rsa decode because some uses of this function get hash implicitly
+     * from the RSA signature itself. */
+    if ((NSS_GetAlgorithmPolicy(cx->hashAlg, &policyFlags) == SECFailure) ||
+        !(policyFlags & NSS_USE_ALG_IN_ANY_SIGNATURE)) {
+        PORT_SetError(SEC_ERROR_SIGNATURE_ALGORITHM_DISABLED);
+        goto loser;
+    }
+
+    if (hash) {
+        *hash = cx->hashAlg;
+    }
+    return cx;
+
+loser:
+    if (cx) {
+        VFY_DestroyContext(cx, PR_TRUE);
+    }
+    return 0;
+}
+
+VFYContext *
+VFY_CreateContext(SECKEYPublicKey *key, SECItem *sig, SECOidTag sigAlg,
+                  void *wincx)
+{
+    SECOidTag encAlg, hashAlg;
+    SECStatus rv = sec_DecodeSigAlg(key, sigAlg, NULL, &encAlg, &hashAlg);
+    if (rv != SECSuccess) {
+        return NULL;
+    }
+    return vfy_CreateContext(key, sig, encAlg, hashAlg, NULL, wincx);
+}
+
+VFYContext *
+VFY_CreateContextDirect(const SECKEYPublicKey *key, const SECItem *sig,
+                        SECOidTag encAlg, SECOidTag hashAlg,
+                        SECOidTag *hash, void *wincx)
+{
+    return vfy_CreateContext(key, sig, encAlg, hashAlg, hash, wincx);
+}
+
+VFYContext *
+VFY_CreateContextWithAlgorithmID(const SECKEYPublicKey *key, const SECItem *sig,
+                                 const SECAlgorithmID *sigAlgorithm, SECOidTag *hash, void *wincx)
+{
+    VFYContext *cx;
+    SECOidTag encAlg, hashAlg;
+    SECStatus rv = sec_DecodeSigAlg(key,
+                                    SECOID_GetAlgorithmTag((SECAlgorithmID *)sigAlgorithm),
+                                    &sigAlgorithm->parameters, &encAlg, &hashAlg);
+    if (rv != SECSuccess) {
+        return NULL;
+    }
+
+    cx = vfy_CreateContext(key, sig, encAlg, hashAlg, hash, wincx);
+    if (sigAlgorithm->parameters.data) {
+        cx->params = SECITEM_DupItem(&sigAlgorithm->parameters);
+    }
+
+    return cx;
+}
+
+void
+VFY_DestroyContext(VFYContext *cx, PRBool freeit)
+{
+    if (cx) {
+        if (cx->hashcx != NULL) {
+            (*cx->hashobj->destroy)(cx->hashcx, PR_TRUE);
+            cx->hashcx = NULL;
+        }
+        if (cx->key) {
+            SECKEY_DestroyPublicKey(cx->key);
+        }
+        if (cx->pkcs1RSADigestInfo) {
+            PORT_Free(cx->pkcs1RSADigestInfo);
+        }
+        if (cx->params) {
+            SECITEM_FreeItem(cx->params, PR_TRUE);
+        }
+        if (freeit) {
+            PORT_ZFree(cx, sizeof(VFYContext));
+        }
+    }
+}
+
+SECStatus
+VFY_Begin(VFYContext *cx)
+{
+    if (cx->hashcx != NULL) {
+        (*cx->hashobj->destroy)(cx->hashcx, PR_TRUE);
+        cx->hashcx = NULL;
+    }
+
+    cx->hashobj = HASH_GetHashObjectByOidTag(cx->hashAlg);
+    if (!cx->hashobj)
+        return SECFailure; /* error code is set */
+
+    cx->hashcx = (*cx->hashobj->create)();
+    if (cx->hashcx == NULL)
+        return SECFailure;
+
+    (*cx->hashobj->begin)(cx->hashcx);
+    return SECSuccess;
+}
+
+SECStatus
+VFY_Update(VFYContext *cx, const unsigned char *input, unsigned inputLen)
+{
+    if (cx->hashcx == NULL) {
+        PORT_SetError(SEC_ERROR_INVALID_ARGS);
+        return SECFailure;
+    }
+    (*cx->hashobj->update)(cx->hashcx, input, inputLen);
+    return SECSuccess;
+}
+
+SECStatus
+VFY_EndWithSignature(VFYContext *cx, SECItem *sig)
+{
+    unsigned char final[HASH_LENGTH_MAX];
+    unsigned part;
+    SECItem hash, rsasig, dsasig; /* dsasig is also used for ECDSA */
+    SECStatus rv;
+
+    if ((cx->hasSignature == PR_FALSE) && (sig == NULL)) {
+        PORT_SetError(SEC_ERROR_INVALID_ARGS);
+        return SECFailure;
+    }
+
+    if (cx->hashcx == NULL) {
+        PORT_SetError(SEC_ERROR_INVALID_ARGS);
+        return SECFailure;
+    }
+    (*cx->hashobj->end)(cx->hashcx, final, &part, sizeof(final));
+    switch (cx->key->keyType) {
+        case ecKey:
+        case dsaKey:
+            dsasig.len = checkedSignatureLen(cx->key);
+            if (dsasig.len == 0) {
+                return SECFailure;
+            }
+            if (dsasig.len > sizeof(cx->u)) {
+                PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                return SECFailure;
+            }
+            dsasig.data = cx->u.buffer;
+
+            if (sig) {
+                rv = decodeECorDSASignature(cx->encAlg, sig, dsasig.data,
+                                            dsasig.len);
+                if (rv != SECSuccess) {
+                    PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                    return SECFailure;
+                }
+            }
+            hash.data = final;
+            hash.len = part;
+            if (PK11_Verify(cx->key, &dsasig, &hash, cx->wincx) != SECSuccess) {
+                PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                return SECFailure;
+            }
+            break;
+        case rsaKey:
+            if (cx->encAlg == SEC_OID_PKCS1_RSA_PSS_SIGNATURE) {
+                CK_RSA_PKCS_PSS_PARAMS mech;
+                SECItem mechItem = { siBuffer, (unsigned char *)&mech, sizeof(mech) };
+                PORTCheapArenaPool tmpArena;
+
+                PORT_InitCheapArena(&tmpArena, DER_DEFAULT_CHUNKSIZE);
+                rv = sec_DecodeRSAPSSParamsToMechanism(&tmpArena.arena,
+                                                       cx->params,
+                                                       &mech);
+                PORT_DestroyCheapArena(&tmpArena);
+                if (rv != SECSuccess) {
+                    return SECFailure;
+                }
+
+                rsasig.data = cx->u.buffer;
+                rsasig.len = checkedSignatureLen(cx->key);
+                if (rsasig.len == 0) {
+                    /* Error set by checkedSignatureLen */
+                    return SECFailure;
+                }
+                if (rsasig.len > sizeof(cx->u)) {
+                    PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                    return SECFailure;
+                }
+                if (sig) {
+                    if (sig->len != rsasig.len) {
+                        PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                        return SECFailure;
+                    }
+                    PORT_Memcpy(rsasig.data, sig->data, rsasig.len);
+                }
+                hash.data = final;
+                hash.len = part;
+                if (PK11_VerifyWithMechanism(cx->key, CKM_RSA_PKCS_PSS, &mechItem,
+                                             &rsasig, &hash, cx->wincx) != SECSuccess) {
+                    PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                    return SECFailure;
+                }
+            } else {
+                SECItem digest;
+                digest.data = final;
+                digest.len = part;
+                if (sig) {
+                    SECOidTag hashid;
+                    PORT_Assert(cx->hashAlg != SEC_OID_UNKNOWN);
+                    rv = recoverPKCS1DigestInfo(cx->hashAlg, &hashid,
+                                                &cx->pkcs1RSADigestInfo,
+                                                &cx->pkcs1RSADigestInfoLen,
+                                                cx->key,
+                                                sig, cx->wincx);
+                    if (rv != SECSuccess) {
+                        return SECFailure;
+                    }
+                    PORT_Assert(cx->hashAlg == hashid);
+                }
+                return verifyPKCS1DigestInfo(cx, &digest);
+            }
+            break;
+        default:
+            PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+            return SECFailure; /* shouldn't happen */
+    }
+    return SECSuccess;
+}
+
+SECStatus
+VFY_End(VFYContext *cx)
+{
+    return VFY_EndWithSignature(cx, NULL);
+}
+
+/************************************************************************/
+/*
+ * Verify that a previously-computed digest matches a signature.
+ */
+static SECStatus
+vfy_VerifyDigest(const SECItem *digest, const SECKEYPublicKey *key,
+                 const SECItem *sig, SECOidTag encAlg, SECOidTag hashAlg,
+                 void *wincx)
+{
+    SECStatus rv;
+    VFYContext *cx;
+    SECItem dsasig; /* also used for ECDSA */
+    rv = SECFailure;
+
+    cx = vfy_CreateContext(key, sig, encAlg, hashAlg, NULL, wincx);
+    if (cx != NULL) {
+        switch (key->keyType) {
+            case rsaKey:
+                rv = verifyPKCS1DigestInfo(cx, digest);
+                /* Error (if any) set by verifyPKCS1DigestInfo */
+                break;
+            case ecKey:
+            case dsaKey:
+                dsasig.data = cx->u.buffer;
+                dsasig.len = checkedSignatureLen(cx->key);
+                if (dsasig.len == 0) {
+                    /* Error set by checkedSignatureLen */
+                    rv = SECFailure;
+                    break;
+                }
+                if (dsasig.len > sizeof(cx->u)) {
+                    PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                    rv = SECFailure;
+                    break;
+                }
+                rv = PK11_Verify(cx->key, &dsasig, (SECItem *)digest, cx->wincx);
+                if (rv != SECSuccess) {
+                    PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+                }
+                break;
+            default:
+                break;
+        }
+        VFY_DestroyContext(cx, PR_TRUE);
+    }
+    return rv;
+}
+
+SECStatus
+VFY_VerifyDigestDirect(const SECItem *digest, const SECKEYPublicKey *key,
+                       const SECItem *sig, SECOidTag encAlg,
+                       SECOidTag hashAlg, void *wincx)
+{
+    return vfy_VerifyDigest(digest, key, sig, encAlg, hashAlg, wincx);
+}
+
+SECStatus
+VFY_VerifyDigest(SECItem *digest, SECKEYPublicKey *key, SECItem *sig,
+                 SECOidTag algid, void *wincx)
+{
+    SECOidTag encAlg, hashAlg;
+    SECStatus rv = sec_DecodeSigAlg(key, algid, NULL, &encAlg, &hashAlg);
+    if (rv != SECSuccess) {
+        return SECFailure;
+    }
+    return vfy_VerifyDigest(digest, key, sig, encAlg, hashAlg, wincx);
+}
+
+/*
+ * this function takes an optional hash oid, which the digest function
+ * will be compared with our target hash value.
+ */
+SECStatus
+VFY_VerifyDigestWithAlgorithmID(const SECItem *digest,
+                                const SECKEYPublicKey *key, const SECItem *sig,
+                                const SECAlgorithmID *sigAlgorithm,
+                                SECOidTag hashCmp, void *wincx)
+{
+    SECOidTag encAlg, hashAlg;
+    SECStatus rv = sec_DecodeSigAlg(key,
+                                    SECOID_GetAlgorithmTag((SECAlgorithmID *)sigAlgorithm),
+                                    &sigAlgorithm->parameters, &encAlg, &hashAlg);
+    if (rv != SECSuccess) {
+        return rv;
+    }
+    if (hashCmp != SEC_OID_UNKNOWN &&
+        hashAlg != SEC_OID_UNKNOWN &&
+        hashCmp != hashAlg) {
+        PORT_SetError(SEC_ERROR_BAD_SIGNATURE);
+        return SECFailure;
+    }
+    return vfy_VerifyDigest(digest, key, sig, encAlg, hashAlg, wincx);
+}
+
+static SECStatus
+vfy_VerifyData(const unsigned char *buf, int len, const SECKEYPublicKey *key,
+               const SECItem *sig, SECOidTag encAlg, SECOidTag hashAlg,
+               const SECItem *params, SECOidTag *hash, void *wincx)
+{
+    SECStatus rv;
+    VFYContext *cx;
+
+    cx = vfy_CreateContext(key, sig, encAlg, hashAlg, hash, wincx);
+    if (cx == NULL)
+        return SECFailure;
+    if (params) {
+        cx->params = SECITEM_DupItem(params);
+    }
+
+    rv = VFY_Begin(cx);
+    if (rv == SECSuccess) {
+        rv = VFY_Update(cx, (unsigned char *)buf, len);
+        if (rv == SECSuccess)
+            rv = VFY_End(cx);
+    }
+
+    VFY_DestroyContext(cx, PR_TRUE);
+    return rv;
+}
+
+SECStatus
+VFY_VerifyDataDirect(const unsigned char *buf, int len,
+                     const SECKEYPublicKey *key, const SECItem *sig,
+                     SECOidTag encAlg, SECOidTag hashAlg,
+                     SECOidTag *hash, void *wincx)
+{
+    return vfy_VerifyData(buf, len, key, sig, encAlg, hashAlg, NULL, hash, wincx);
+}
+
+SECStatus
+VFY_VerifyData(const unsigned char *buf, int len, const SECKEYPublicKey *key,
+               const SECItem *sig, SECOidTag algid, void *wincx)
+{
+    SECOidTag encAlg, hashAlg;
+    SECStatus rv = sec_DecodeSigAlg(key, algid, NULL, &encAlg, &hashAlg);
+    if (rv != SECSuccess) {
+        return rv;
+    }
+    return vfy_VerifyData(buf, len, key, sig, encAlg, hashAlg, NULL, NULL, wincx);
+}
+
+SECStatus
+VFY_VerifyDataWithAlgorithmID(const unsigned char *buf, int len,
+                              const SECKEYPublicKey *key,
+                              const SECItem *sig,
+                              const SECAlgorithmID *sigAlgorithm,
+                              SECOidTag *hash, void *wincx)
+{
+    SECOidTag encAlg, hashAlg;
+    SECOidTag sigAlg = SECOID_GetAlgorithmTag((SECAlgorithmID *)sigAlgorithm);
+    SECStatus rv = sec_DecodeSigAlg(key, sigAlg,
+                                    &sigAlgorithm->parameters, &encAlg, &hashAlg);
+    if (rv != SECSuccess) {
+        return rv;
+    }
+    return vfy_VerifyData(buf, len, key, sig, encAlg, hashAlg,
+                          &sigAlgorithm->parameters, hash, wincx);
+}