Adding upstream version 124.0.1.upstream/124.0.1

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

1 files changed, 1520 insertions, 0 deletions

diff --git a/security/nss/lib/softoken/kbkdf.c b/security/nss/lib/softoken/kbkdf.c
new file mode 100644
index 0000000000..c6021ef5e5
--- /dev/null
+++ b/security/nss/lib/softoken/kbkdf.c
@@ -0,0 +1,1520 @@
+#include "pkcs11i.h"
+#include "blapi.h"
+#include "secerr.h"
+#include "softoken.h"
+
+/* Overview:
+ *
+ * This file contains implementations of the three KDFs from NIST SP800-108
+ * "Recommendation for Key Derivation Using Pseudorandom Functions":
+ *
+ *  1. KDF in Counter Mode (section 5.1)
+ *  2. KDF in Feedback Mode (section 5.2)
+ *  3. KDF in Double-Pipeline Iteration Mode (section 5.3)
+ *
+ * These KDFs are a form of negotiable building blocks for KDFs: protocol
+ * designers can choose various fields, their endianness, and the underlying
+ * PRF. These constructs are generic enough to handle creation of arbitrary,
+ * (but known ahead of time) length outputs.
+ *
+ * The families of PRFs described here are used, among other places, in
+ * Kerberos and GlobalPlatform's Secure Channel Protocol 03. The PKCS#11 v3.0
+ * design for this KDF facilitates a wide range of uses.
+ *
+ * Implementation Details:
+ *
+ * We reuse the new sftk_MACCtx for handling the underlying MACing; with a few
+ * safe restrictions, we can reuse whatever it gives us to use as a PRF.
+ *
+ * We implement the core of the KDF in the *Raw(...) version of the function
+ * call. The PKCS#11 key handling happens in the non-Raw version. This means
+ * we need a single large allocation upfront (large enough to store the entire
+ * key stream), but means we can share key parsing logic and enable the
+ * creation of data objects.
+ */
+
+/* [ section: #define's ] */
+
+#define VALID_CK_BOOL(x) ((x) == CK_TRUE || (x) == CK_FALSE)
+#define IS_COUNTER(_mech) ((_mech) == CKM_SP800_108_COUNTER_KDF || (_mech) == CKM_NSS_SP800_108_COUNTER_KDF_DERIVE_DATA)
+#define DOES_DERIVE_DATA(_mech) ((_mech) == CKM_NSS_SP800_108_COUNTER_KDF_DERIVE_DATA || (_mech) == CKM_NSS_SP800_108_FEEDBACK_KDF_DERIVE_DATA || (_mech) == CKM_NSS_SP800_108_DOUBLE_PIPELINE_KDF_DERIVE_DATA)
+
+/* [ section: parameter validation ] */
+
+static CK_RV
+kbkdf_LoadParameters(CK_MECHANISM_TYPE mech, CK_MECHANISM_PTR pMechanism, CK_SP800_108_KDF_PARAMS_PTR kdf_params, CK_BYTE_PTR *initial_value, CK_ULONG_PTR initial_value_length)
+{
+    /* This function loads the parameters for the given mechanism into the
+     * specified kdf_params, splitting off the IV if present. In PKCS#11 v3.0,
+     * CK_SP800_108_FEEDBACK_KDF_PARAMS and CK_SP800_108_KDF_PARAMS have
+     * different ordering of internal parameters, which means that it isn't
+     * easy to reuse feedback parameters in the same functions as non-feedback
+     * parameters. Rather than duplicating the logic, split out the only
+     * Feedback-specific data (the IV) into a separate argument and repack it
+     * into the passed kdf_params struct instead. */
+    PR_ASSERT(pMechanism != NULL && kdf_params != NULL && initial_value != NULL && initial_value_length != NULL);
+
+    CK_SP800_108_KDF_PARAMS_PTR in_params;
+    CK_SP800_108_FEEDBACK_KDF_PARAMS_PTR feedback_params;
+
+    if (mech == CKM_SP800_108_FEEDBACK_KDF || mech == CKM_NSS_SP800_108_FEEDBACK_KDF_DERIVE_DATA) {
+        if (pMechanism->ulParameterLen != sizeof(CK_SP800_108_FEEDBACK_KDF_PARAMS)) {
+            return CKR_MECHANISM_PARAM_INVALID;
+        }
+
+        feedback_params = (CK_SP800_108_FEEDBACK_KDF_PARAMS *)pMechanism->pParameter;
+
+        if (feedback_params->pIV == NULL && feedback_params->ulIVLen > 0) {
+            return CKR_MECHANISM_PARAM_INVALID;
+        }
+
+        kdf_params->prfType = feedback_params->prfType;
+        kdf_params->ulNumberOfDataParams = feedback_params->ulNumberOfDataParams;
+        kdf_params->pDataParams = feedback_params->pDataParams;
+        kdf_params->ulAdditionalDerivedKeys = feedback_params->ulAdditionalDerivedKeys;
+        kdf_params->pAdditionalDerivedKeys = feedback_params->pAdditionalDerivedKeys;
+
+        *initial_value = feedback_params->pIV;
+        *initial_value_length = feedback_params->ulIVLen;
+    } else {
+        if (pMechanism->ulParameterLen != sizeof(CK_SP800_108_KDF_PARAMS)) {
+            return CKR_MECHANISM_PARAM_INVALID;
+        }
+
+        in_params = (CK_SP800_108_KDF_PARAMS *)pMechanism->pParameter;
+
+        (*kdf_params) = *in_params;
+    }
+
+    return CKR_OK;
+}
+
+static CK_RV
+kbkdf_ValidateParameter(CK_MECHANISM_TYPE mech, const CK_PRF_DATA_PARAM *data)
+{
+    /* This function validates that the passed data parameter (data) conforms
+     * to PKCS#11 v3.0's expectations for KDF parameters. This depends both on
+     * the type of this parameter (data->type) and on the KDF mechanism (mech)
+     * as certain parameters are context dependent (like Iteration Variable).
+     */
+
+    /* If the parameter is missing a value when one is expected, then this
+     * parameter is invalid. */
+    if ((data->pValue == NULL) != (data->ulValueLen == 0)) {
+        return CKR_MECHANISM_PARAM_INVALID;
+    }
+
+    switch (data->type) {
+        case CK_SP800_108_ITERATION_VARIABLE:
+        case CK_SP800_108_OPTIONAL_COUNTER: {
+            if (data->type == CK_SP800_108_ITERATION_VARIABLE && !IS_COUNTER(mech)) {
+                /* In Feedback and Double Pipeline KDFs, PKCS#11 v3.0 connotes the
+                 * iteration variable as the chaining value from the previous PRF
+                 * invocation. In contrast, counter mode treats this variable as a
+                 * COUNTER_FORMAT descriptor. Thus we can skip validation of
+                 * iteration variable parameters outside of counter mode. However,
+                 * PKCS#11 v3.0 technically mandates that pValue is NULL, so we
+                 * still have to validate that. */
+
+                if (data->pValue != NULL) {
+                    return CKR_MECHANISM_PARAM_INVALID;
+                }
+
+                return CKR_OK;
+            }
+
+            /* In counter mode, data->pValue should be a pointer to an instance of
+             * CK_SP800_108_COUNTER_FORMAT; validate its length. */
+            if (data->ulValueLen != sizeof(CK_SP800_108_COUNTER_FORMAT)) {
+                return CKR_MECHANISM_PARAM_INVALID;
+            }
+
+            CK_SP800_108_COUNTER_FORMAT_PTR param = (CK_SP800_108_COUNTER_FORMAT_PTR)data->pValue;
+
+            /* Validate the endian parameter. */
+            if (!VALID_CK_BOOL(param->bLittleEndian)) {
+                return CKR_MECHANISM_PARAM_INVALID;
+            }
+
+            /* Due to restrictions by our underlying hashes, we restrict bit
+             * widths to actually be byte widths by ensuring they're a multiple
+             * of eight. */
+            if ((param->ulWidthInBits % 8) != 0) {
+                return CKR_MECHANISM_PARAM_INVALID;
+            }
+
+            /* Note that section 5.1 denotes the maximum length of the counter
+             * to be 32. */
+            if (param->ulWidthInBits > 32) {
+                return CKR_MECHANISM_PARAM_INVALID;
+            }
+            break;
+        }
+        case CK_SP800_108_DKM_LENGTH: {
+            /* data->pValue should be a pointer to an instance of
+             * CK_SP800_108_DKM_LENGTH_FORMAT; validate its length. */
+            if (data->ulValueLen != sizeof(CK_SP800_108_DKM_LENGTH_FORMAT)) {
+                return CKR_MECHANISM_PARAM_INVALID;
+            }
+
+            CK_SP800_108_DKM_LENGTH_FORMAT_PTR param = (CK_SP800_108_DKM_LENGTH_FORMAT_PTR)data->pValue;
+
+            /* Validate the method parameter. */
+            if (param->dkmLengthMethod != CK_SP800_108_DKM_LENGTH_SUM_OF_KEYS &&
+                param->dkmLengthMethod != CK_SP800_108_DKM_LENGTH_SUM_OF_SEGMENTS) {
+                return CKR_MECHANISM_PARAM_INVALID;
+            }
+
+            /* Validate the endian parameter. */
+            if (!VALID_CK_BOOL(param->bLittleEndian)) {
+                return CKR_MECHANISM_PARAM_INVALID;
+            }
+
+            /* Validate the maximum width: we restrict it to being a byte width
+             * instead of a bit width due to restrictions by the underlying
+             * PRFs. */
+            if ((param->ulWidthInBits % 8) != 0) {
+                return CKR_MECHANISM_PARAM_INVALID;
+            }
+
+            /* Ensure that the width doesn't overflow a 64-bit int. This
+             * restriction is arbitrary but since the counters can't exceed
+             * 32-bits (and most PRFs output at most 1024 bits), you're unlikely
+             * to need all 64-bits of length indicator. */
+            if (param->ulWidthInBits > 64) {
+                return CKR_MECHANISM_PARAM_INVALID;
+            }
+            break;
+        }
+        case CK_SP800_108_BYTE_ARRAY:
+            /* There is no additional data to validate for byte arrays; we can
+             * only assume the byte array is of the specified size. */
+            break;
+        default:
+            /* Unexpected parameter type. */
+            return CKR_MECHANISM_PARAM_INVALID;
+    }
+
+    return CKR_OK;
+}
+
+static CK_RV
+kbkdf_ValidateDerived(CK_DERIVED_KEY_PTR key)
+{
+    CK_KEY_TYPE keyType = CKK_GENERIC_SECRET;
+    PRUint64 keySize = 0;
+
+    /* The pointer to the key handle shouldn't be NULL. If it is, we can't
+     * do anything else, so exit early. Every other failure case sets the
+     * key->phKey = CK_INVALID_HANDLE, so we can't use `goto failure` here. */
+    if (key->phKey == NULL) {
+        return CKR_MECHANISM_PARAM_INVALID;
+    }
+
+    /* Validate that we have no attributes if and only if pTemplate is NULL.
+     * Otherwise, there's an inconsistency somewhere. */
+    if ((key->ulAttributeCount == 0) != (key->pTemplate == NULL)) {
+        goto failure;
+    }
+
+    for (size_t offset = 0; offset < key->ulAttributeCount; offset++) {
+        CK_ATTRIBUTE_PTR template = key->pTemplate + offset;
+
+        /* We only look for the CKA_VALUE_LEN and CKA_KEY_TYPE attributes.
+         * Everything else we assume we can set on the key if it is passed
+         * here. However, if we can't inquire as to a length (and barring
+         * that, if we have a key type without a standard length), we're
+         * definitely stuck. This mirrors the logic at the top of
+         * NSC_DeriveKey(...). */
+        if (template->type == CKA_KEY_TYPE) {
+            if (template->ulValueLen != sizeof(CK_KEY_TYPE)) {
+                goto failure;
+            }
+
+            keyType = *(CK_KEY_TYPE *)template->pValue;
+        } else if (template->type == CKA_VALUE_LEN) {
+            if (template->ulValueLen != sizeof(CK_ULONG)) {
+                goto failure;
+            }
+
+            keySize = *(CK_ULONG *)template->pValue;
+        }
+    }
+
+    if (keySize == 0) {
+        /* When we lack a keySize, see if we can infer it from the type of the
+         * passed key. */
+        keySize = sftk_MapKeySize(keyType);
+    }
+
+    /* The main piece of information we validate is that we have a length for
+     * this key. */
+    if (keySize == 0 || keySize >= (1ull << 32ull)) {
+        goto failure;
+    }
+
+    return CKR_OK;
+
+failure:
+    /* PKCS#11 v3.0: If the failure was caused by the content of a specific
+     * key's template (ie the template defined by the content of pTemplate),
+     * the corresponding phKey value will be set to CK_INVALID_HANDLE to
+     * identify the offending template. */
+    *(key->phKey) = CK_INVALID_HANDLE;
+    return CKR_MECHANISM_PARAM_INVALID;
+}
+
+static CK_RV
+kbkdf_ValidateParameters(CK_MECHANISM_TYPE mech, const CK_SP800_108_KDF_PARAMS *params, CK_ULONG keySize)
+{
+    CK_RV ret = CKR_MECHANISM_PARAM_INVALID;
+    int param_type_count[5] = { 0, 0, 0, 0, 0 };
+    size_t offset = 0;
+
+    /* Start with checking the prfType as a mechanism against a list of
+     * PRFs allowed by PKCS#11 v3.0. */
+    if (!(/* The following types aren't defined in NSS yet. */
+          /* params->prfType != CKM_3DES_CMAC && */
+          params->prfType == CKM_AES_CMAC || /* allow */
+          /* We allow any HMAC except MD2 and MD5. */
+          params->prfType != CKM_MD2_HMAC ||                        /* disallow */
+          params->prfType != CKM_MD5_HMAC ||                        /* disallow */
+          sftk_HMACMechanismToHash(params->prfType) != HASH_AlgNULL /* Valid HMAC <-> HASH isn't NULL */
+          )) {
+        return CKR_MECHANISM_PARAM_INVALID;
+    }
+
+    /* We can't have a null pDataParams pointer: we always need at least one
+     * parameter to succeed. */
+    if (params->pDataParams == NULL) {
+        return CKR_HOST_MEMORY;
+    }
+
+    /* Validate each KDF parameter. */
+    for (offset = 0; offset < params->ulNumberOfDataParams; offset++) {
+        /* Validate this parameter has acceptable values. */
+        ret = kbkdf_ValidateParameter(mech, params->pDataParams + offset);
+        if (ret != CKR_OK) {
+            return CKR_MECHANISM_PARAM_INVALID;
+        }
+
+        /* Count that we have a parameter of this type. The above logic
+         * in ValidateParameter MUST validate that type is within the
+         * appropriate range. */
+        PR_ASSERT(params->pDataParams[offset].type < sizeof(param_type_count) / sizeof(param_type_count[0]));
+        param_type_count[params->pDataParams[offset].type] += 1;
+    }
+
+    if (IS_COUNTER(mech)) {
+        /* We have to have at least one iteration variable parameter. */
+        if (param_type_count[CK_SP800_108_ITERATION_VARIABLE] == 0) {
+            return CKR_MECHANISM_PARAM_INVALID;
+        }
+
+        /* We can't have any optional counters parameters -- these belong in
+         * iteration variable parameters instead. */
+        if (param_type_count[CK_SP800_108_OPTIONAL_COUNTER] != 0) {
+            return CKR_MECHANISM_PARAM_INVALID;
+        }
+    }
+
+    /* Validate basic assumptions about derived keys:
+     *      NULL <-> ulAdditionalDerivedKeys > 0
+     */
+    if ((params->ulAdditionalDerivedKeys == 0) != (params->pAdditionalDerivedKeys == NULL)) {
+        return CKR_MECHANISM_PARAM_INVALID;
+    }
+
+    /* Validate each derived key. */
+    for (offset = 0; offset < params->ulAdditionalDerivedKeys; offset++) {
+        ret = kbkdf_ValidateDerived(params->pAdditionalDerivedKeys + offset);
+        if (ret != CKR_OK) {
+            return CKR_MECHANISM_PARAM_INVALID;
+        }
+    }
+
+    /* Validate the length of our primary key. */
+    if (keySize == 0 || ((PRUint64)keySize) >= (1ull << 32ull)) {
+        return CKR_KEY_SIZE_RANGE;
+    }
+
+    return CKR_OK;
+}
+
+/* [ section: parameter helpers ] */
+
+static CK_VOID_PTR
+kbkdf_FindParameter(const CK_SP800_108_KDF_PARAMS *params, CK_PRF_DATA_TYPE type)
+{
+    for (size_t offset = 0; offset < params->ulNumberOfDataParams; offset++) {
+        if (params->pDataParams[offset].type == type) {
+            return params->pDataParams[offset].pValue;
+        }
+    }
+
+    return NULL;
+}
+
+size_t
+kbkdf_IncrementBuffer(size_t cur_offset, size_t consumed, size_t prf_length)
+{
+    return cur_offset + PR_ROUNDUP(consumed, prf_length);
+}
+
+CK_ULONG
+kbkdf_GetDerivedKeySize(CK_DERIVED_KEY_PTR derived_key)
+{
+    /* Precondition: kbkdf_ValidateDerived(...) returns CKR_OK for this key,
+     * which implies that keySize is defined. */
+
+    CK_KEY_TYPE keyType = CKK_GENERIC_SECRET;
+    CK_ULONG keySize = 0;
+
+    for (size_t offset = 0; offset < derived_key->ulAttributeCount; offset++) {
+        CK_ATTRIBUTE_PTR template = derived_key->pTemplate + offset;
+
+        /* Find the two attributes we care about. */
+        if (template->type == CKA_KEY_TYPE) {
+            keyType = *(CK_KEY_TYPE *)template->pValue;
+        } else if (template->type == CKA_VALUE_LEN) {
+            keySize = *(CK_ULONG *)template->pValue;
+        }
+    }
+
+    /* Prefer keySize, if we have it. */
+    if (keySize > 0) {
+        return keySize;
+    }
+
+    /* Else, fall back to this mapping. We know kbkdf_ValidateDerived(...)
+     * passed, so this should return non-zero. */
+    return sftk_MapKeySize(keyType);
+}
+
+static CK_RV
+kbkdf_CalculateLength(const CK_SP800_108_KDF_PARAMS *params, sftk_MACCtx *ctx, CK_ULONG ret_key_size, PRUint64 *output_bitlen, size_t *buffer_length)
+{
+    /* Two cases: either we have additional derived keys or we don't. In the
+     * case that we don't, the length of the derivation is the size of the
+     * single derived key, and that is the length of the PRF buffer. Otherwise,
+     * we need to use the proper CK_SP800_108_DKM_LENGTH_METHOD to calculate
+     * the length of the output (in bits), with a separate value for the size
+     * of the PRF data buffer. This means that, under PKCS#11 with additional
+     * derived keys, we lie to the KDF about the _actual_ length of the PRF
+     * output.
+     *
+     * Note that *output_bitlen is the L parameter in NIST SP800-108 and is in
+     * bits. However, *buffer_length is in bytes.
+     */
+
+    if (params->ulAdditionalDerivedKeys == 0) {
+        /* When we have no additional derived keys, we get the keySize from
+         * the value passed to one of our KBKDF_* methods. */
+        *output_bitlen = ret_key_size;
+        *buffer_length = ret_key_size;
+    } else {
+        /* Offset in the additional derived keys array. */
+        size_t offset = 0;
+
+        /* Size of the derived key. */
+        CK_ULONG derived_size = 0;
+
+        /* In the below, we place the sum of the keys into *output_bitlen
+         * and the size of the buffer (with padding mandated by PKCS#11 v3.0)
+         * into *buffer_length. If the method is the segment sum, then we
+         * replace *output_bitlen with *buffer_length at the end. This ensures
+         * we always get a output buffer large enough to handle all derived
+         * keys, and *output_bitlen reflects the correct L value. */
+
+        /* Count the initial derived key. */
+        *output_bitlen = ret_key_size;
+        *buffer_length = kbkdf_IncrementBuffer(0, ret_key_size, ctx->mac_size);
+
+        /* Handle n - 1 keys. The last key is special. */
+        for (; offset < params->ulAdditionalDerivedKeys - 1; offset++) {
+            derived_size = kbkdf_GetDerivedKeySize(params->pAdditionalDerivedKeys + offset);
+
+            *output_bitlen += derived_size;
+            *buffer_length = kbkdf_IncrementBuffer(*buffer_length, derived_size, ctx->mac_size);
+        }
+
+        /* Handle the last key. */
+        derived_size = kbkdf_GetDerivedKeySize(params->pAdditionalDerivedKeys + offset);
+
+        *output_bitlen += derived_size;
+        *buffer_length = kbkdf_IncrementBuffer(*buffer_length, derived_size, ctx->mac_size);
+
+        /* Pointer to the DKM method parameter. Note that this implicit cast
+         * is safe since we've assumed we've been validated by
+         * kbkdf_ValidateParameters(...). When kdm_param is NULL, we don't
+         * use the output_bitlen parameter. */
+        CK_SP800_108_DKM_LENGTH_FORMAT_PTR dkm_param = kbkdf_FindParameter(params, CK_SP800_108_DKM_LENGTH);
+        if (dkm_param != NULL) {
+            if (dkm_param->dkmLengthMethod == CK_SP800_108_DKM_LENGTH_SUM_OF_SEGMENTS) {
+                *output_bitlen = *buffer_length;
+            }
+        }
+    }
+
+    /* Note that keySize is the size in bytes and ctx->mac_size is also
+     * the size in bytes. However, output_bitlen needs to be in bits, so
+     * multiply by 8 here. */
+    *output_bitlen *= 8;
+
+    return CKR_OK;
+}
+
+static CK_RV
+kbkdf_CalculateIterations(CK_MECHANISM_TYPE mech, const CK_SP800_108_KDF_PARAMS *params, sftk_MACCtx *ctx, size_t buffer_length, PRUint32 *num_iterations)
+{
+    CK_SP800_108_COUNTER_FORMAT_PTR param_ptr = NULL;
+    PRUint64 iteration_count;
+    PRUint64 r = 32;
+
+    /* We need to know how many full iterations are required. This is done
+     * by rounding up the division of the PRF length into buffer_length.
+     * However, we're not guaranteed that the last output is a full PRF
+     * invocation, so handle that here. */
+    iteration_count = buffer_length + (ctx->mac_size - 1);
+    iteration_count = iteration_count / ctx->mac_size;
+
+    /* NIST SP800-108, section 5.1, process step #2:
+     *
+     *      if n > 2^r - 1, then indicate an error and stop.
+     *
+     * In non-counter mode KDFs, r is set at 32, leaving behavior
+     * under-defined when the optional counter is included but fewer than
+     * 32 bits. This implementation assumes r is 32, but if the counter
+     * parameter is included, validates it against that. In counter-mode
+     * KDFs, this is in the ITERATION_VARIABLE parameter; in feedback- or
+     * pipeline-mode KDFs, this is in the COUNTER parameter.
+     *
+     * This is consistent with the supplied sample CAVP tests; none reuses the
+     * same counter value. In some configurations, this could result in
+     * duplicated KDF output. We seek to avoid that from happening.
+     */
+    if (IS_COUNTER(mech)) {
+        param_ptr = kbkdf_FindParameter(params, CK_SP800_108_ITERATION_VARIABLE);
+
+        /* Validated by kbkdf_ValidateParameters(...) above. */
+        PR_ASSERT(param_ptr != NULL);
+
+        r = ((CK_SP800_108_COUNTER_FORMAT_PTR)param_ptr)->ulWidthInBits;
+    } else {
+        param_ptr = kbkdf_FindParameter(params, CK_SP800_108_COUNTER);
+
+        /* Not guaranteed to exist, hence the default value of r=32. */
+        if (param_ptr != NULL) {
+            r = ((CK_SP800_108_COUNTER_FORMAT_PTR)param_ptr)->ulWidthInBits;
+        }
+    }
+
+    if (iteration_count >= (1ull << r) || r > 32) {
+        return CKR_MECHANISM_PARAM_INVALID;
+    }
+
+    *num_iterations = (PRUint32)iteration_count;
+
+    return CKR_OK;
+}
+
+static CK_RV
+kbkdf_AddParameters(CK_MECHANISM_TYPE mech, sftk_MACCtx *ctx, const CK_SP800_108_KDF_PARAMS *params, PRUint32 counter, PRUint64 length, const unsigned char *chaining_prf, size_t chaining_prf_len, CK_PRF_DATA_TYPE exclude)
+{
+    size_t offset = 0;
+    CK_RV ret = CKR_OK;
+
+    for (offset = 0; offset < params->ulNumberOfDataParams; offset++) {
+        CK_PRF_DATA_PARAM_PTR param = params->pDataParams + offset;
+
+        if (param->type == exclude) {
+            /* Necessary for Double Pipeline mode: when constructing the IV,
+             * we skip the  optional counter. */
+            continue;
+        }
+
+        switch (param->type) {
+            case CK_SP800_108_ITERATION_VARIABLE: {
+                /* When present in COUNTER mode, this signifies adding the counter
+                 * variable to the PRF. Otherwise, it signifies the chaining
+                 * value for other KDF modes. */
+                if (IS_COUNTER(mech)) {
+                    CK_SP800_108_COUNTER_FORMAT_PTR counter_format = (CK_SP800_108_COUNTER_FORMAT_PTR)param->pValue;
+                    CK_BYTE buffer[sizeof(PRUint64)];
+                    CK_ULONG num_bytes;
+                    sftk_EncodeInteger(counter, counter_format->ulWidthInBits, counter_format->bLittleEndian, buffer, &num_bytes);
+                    ret = sftk_MAC_Update(ctx, buffer, num_bytes);
+                } else {
+                    ret = sftk_MAC_Update(ctx, chaining_prf, chaining_prf_len);
+                }
+                break;
+            }
+            case CK_SP800_108_COUNTER: {
+                /* Only present in the case when not using COUNTER mode. */
+                PR_ASSERT(!IS_COUNTER(mech));
+
+                /* We should've already validated that this parameter is of
+                 * type COUNTER_FORMAT. */
+                CK_SP800_108_COUNTER_FORMAT_PTR counter_format = (CK_SP800_108_COUNTER_FORMAT_PTR)param->pValue;
+                CK_BYTE buffer[sizeof(PRUint64)];
+                CK_ULONG num_bytes;
+                sftk_EncodeInteger(counter, counter_format->ulWidthInBits, counter_format->bLittleEndian, buffer, &num_bytes);
+                ret = sftk_MAC_Update(ctx, buffer, num_bytes);
+                break;
+            }
+            case CK_SP800_108_BYTE_ARRAY:
+                ret = sftk_MAC_Update(ctx, (CK_BYTE_PTR)param->pValue, param->ulValueLen);
+                break;
+            case CK_SP800_108_DKM_LENGTH: {
+                /* We've already done the hard work of calculating the length in
+                 * the kbkdf_CalculateIterations function; we merely need to add
+                 * the length to the desired point in the input stream. */
+                CK_SP800_108_DKM_LENGTH_FORMAT_PTR length_format = (CK_SP800_108_DKM_LENGTH_FORMAT_PTR)param->pValue;
+                CK_BYTE buffer[sizeof(PRUint64)];
+                CK_ULONG num_bytes;
+                sftk_EncodeInteger(length, length_format->ulWidthInBits, length_format->bLittleEndian, buffer, &num_bytes);
+                ret = sftk_MAC_Update(ctx, buffer, num_bytes);
+                break;
+            }
+            default:
+                /* This should've been caught by kbkdf_ValidateParameters(...). */
+                PR_ASSERT(PR_FALSE);
+                return CKR_MECHANISM_PARAM_INVALID;
+        }
+
+        if (ret != CKR_OK) {
+            return ret;
+        }
+    }
+
+    return CKR_OK;
+}
+
+CK_RV
+kbkdf_SaveKey(SFTKObject *key, unsigned char *key_buffer, unsigned int key_len)
+{
+    return sftk_forceAttribute(key, CKA_VALUE, key_buffer, key_len);
+}
+
+CK_RV
+kbkdf_CreateKey(CK_MECHANISM_TYPE kdf_mech, CK_SESSION_HANDLE hSession, CK_DERIVED_KEY_PTR derived_key, SFTKObject **ret_key)
+{
+    /* Largely duplicated from NSC_DeriveKey(...) */
+    CK_RV ret = CKR_HOST_MEMORY;
+    SFTKObject *key = NULL;
+    SFTKSlot *slot = sftk_SlotFromSessionHandle(hSession);
+    size_t offset = 0;
+
+    /* Slot should be non-NULL because NSC_DeriveKey(...) has already
+     * performed a sftk_SlotFromSessionHandle(...) call on this session
+     * handle. However, Coverity incorrectly flagged this (see 1607955). */
+    PR_ASSERT(slot != NULL);
+    PR_ASSERT(ret_key != NULL);
+    PR_ASSERT(derived_key != NULL);
+    PR_ASSERT(derived_key->phKey != NULL);
+
+    if (slot == NULL) {
+        return CKR_SESSION_HANDLE_INVALID;
+    }
+
+    /* Create the new key object for this additional derived key. */
+    key = sftk_NewObject(slot);
+    if (key == NULL) {
+        return CKR_HOST_MEMORY;
+    }
+
+    /* Setup the key from the provided template. */
+    for (offset = 0; offset < derived_key->ulAttributeCount; offset++) {
+        ret = sftk_AddAttributeType(key, sftk_attr_expand(derived_key->pTemplate + offset));
+        if (ret != CKR_OK) {
+            sftk_FreeObject(key);
+            return ret;
+        }
+    }
+
+    /* When using the CKM_SP800_* series of mechanisms, the result must be a
+     * secret key, so its contents can be adequately protected in FIPS mode.
+     * However, when using the special CKM_NSS_SP800_*_DERIVE_DATA series, the
+     * contents need not be protected, so we set CKO_DATA on these "keys". */
+    CK_OBJECT_CLASS classType = CKO_SECRET_KEY;
+    if (DOES_DERIVE_DATA(kdf_mech)) {
+        classType = CKO_DATA;
+    }
+
+    ret = sftk_forceAttribute(key, CKA_CLASS, &classType, sizeof(classType));
+    if (ret != CKR_OK) {
+        sftk_FreeObject(key);
+        return ret;
+    }
+
+    *ret_key = key;
+    return CKR_OK;
+}
+
+CK_RV
+kbkdf_FinalizeKey(CK_SESSION_HANDLE hSession, CK_DERIVED_KEY_PTR derived_key, SFTKObject *key)
+{
+    /* Largely duplicated from NSC_DeriveKey(...) */
+    CK_RV ret = CKR_HOST_MEMORY;
+    SFTKSession *session = NULL;
+
+    PR_ASSERT(derived_key != NULL && key != NULL);
+
+    SFTKSessionObject *sessionForKey = sftk_narrowToSessionObject(key);
+    PR_ASSERT(sessionForKey != NULL);
+    sessionForKey->wasDerived = PR_TRUE;
+
+    session = sftk_SessionFromHandle(hSession);
+
+    /* Session should be non-NULL because NSC_DeriveKey(...) has already
+     * performed a sftk_SessionFromHandle(...) call on this session handle. */
+    PR_ASSERT(session != NULL);
+
+    ret = sftk_handleObject(key, session);
+    if (ret != CKR_OK) {
+        goto done;
+    }
+
+    *(derived_key->phKey) = key->handle;
+
+done:
+    /* Guaranteed that key != NULL */
+    sftk_FreeObject(key);
+
+    /* Doesn't do anything. */
+    if (session) {
+        sftk_FreeSession(session);
+    }
+
+    return ret;
+}
+
+CK_RV
+kbkdf_SaveKeys(CK_MECHANISM_TYPE mech, CK_SESSION_HANDLE hSession, CK_SP800_108_KDF_PARAMS_PTR params, unsigned char *output_buffer, size_t buffer_len, size_t prf_length, SFTKObject *ret_key, CK_ULONG ret_key_size)
+{
+    CK_RV ret;
+    size_t key_offset = 0;
+    size_t buffer_offset = 0;
+
+    PR_ASSERT(output_buffer != NULL && buffer_len > 0 && ret_key != NULL);
+
+    /* First place key material into the main key. */
+    ret = kbkdf_SaveKey(ret_key, output_buffer + buffer_offset, ret_key_size);
+    if (ret != CKR_OK) {
+        return ret;
+    }
+
+    /* Then increment the offset based on PKCS#11 additional key guidelines:
+     * no two keys may share the key stream from the same PRF invocation. */
+    buffer_offset = kbkdf_IncrementBuffer(buffer_offset, ret_key_size, prf_length);
+
+    if (params->ulAdditionalDerivedKeys > 0) {
+        /* Note that the following code is technically incorrect: PKCS#11 v3.0
+         * says that _no_ key should be set in the event of failure to derive
+         * _any_ key. */
+        for (key_offset = 0; key_offset < params->ulAdditionalDerivedKeys; key_offset++) {
+            CK_DERIVED_KEY_PTR derived_key = params->pAdditionalDerivedKeys + key_offset;
+            SFTKObject *key_obj = NULL;
+            size_t key_size = kbkdf_GetDerivedKeySize(derived_key);
+
+            /* Create a new internal key object for this derived key. */
+            ret = kbkdf_CreateKey(mech, hSession, derived_key, &key_obj);
+            if (ret != CKR_OK) {
+                *(derived_key->phKey) = CK_INVALID_HANDLE;
+                return ret;
+            }
+
+            /* Save the underlying key bytes to the key object. */
+            ret = kbkdf_SaveKey(key_obj, output_buffer + buffer_offset, key_size);
+            if (ret != CKR_OK) {
+                /* When kbkdf_CreateKey(...) exits with an error, it will free
+                 * the constructed key object. kbkdf_FinalizeKey(...) also
+                 * always frees the key object. In the unlikely event that
+                 * kbkdf_SaveKey(...) _does_ fail, we thus need to free it
+                 * manually. */
+                sftk_FreeObject(key_obj);
+                *(derived_key->phKey) = CK_INVALID_HANDLE;
+                return ret;
+            }
+
+            /* Handle the increment. */
+            buffer_offset = kbkdf_IncrementBuffer(buffer_offset, key_size, prf_length);
+
+            /* Finalize this key. */
+            ret = kbkdf_FinalizeKey(hSession, derived_key, key_obj);
+            if (ret != CKR_OK) {
+                *(derived_key->phKey) = CK_INVALID_HANDLE;
+                return ret;
+            }
+        }
+    }
+
+    return CKR_OK;
+}
+
+/* [ section: KDFs ] */
+
+static CK_RV
+kbkdf_CounterRaw(const CK_SP800_108_KDF_PARAMS *params, sftk_MACCtx *ctx, unsigned char *ret_buffer, size_t buffer_length, PRUint64 output_bitlen)
+{
+    CK_RV ret = CKR_OK;
+
+    /* Counter variable for this KDF instance. */
+    PRUint32 counter;
+
+    /* Number of iterations required of this PRF necessary to reach the
+     * desired output length. */
+    PRUint32 num_iterations;
+
+    /* Offset in ret_buffer that we're at. */
+    size_t buffer_offset = 0;
+
+    /* Size of this block, in bytes. Defaults to ctx->mac_size except on
+     * the last iteration where it could be a partial block. */
+    size_t block_size = ctx->mac_size;
+
+    /* Calculate the number of iterations required based on the size of the
+     * output buffer. */
+    ret = kbkdf_CalculateIterations(CKM_SP800_108_COUNTER_KDF, params, ctx, buffer_length, &num_iterations);
+    if (ret != CKR_OK) {
+        return ret;
+    }
+
+    /*
+     * 5.1 - [ KDF in Counter Mode ]
+     *
+     * Fixed values:
+     *      1. h - the length of the PRF in bits (ctx->mac_size)
+     *      2. r - the length of the binary representation of the counter i
+     *          (params[k: params[k].type == CK_SP800_108_ITERATION_VARIABLE:].data->ulWidthInBits)
+     * Input:
+     *      1. K_I - the key for the PRF (base_key)
+     *      2. label - a binary data field, usually before the separator. Optional.
+     *      3. context - a binary data field, usually after the separator. Optional.
+     *      4. L - length of the output in bits (output_bitlen)
+     *
+     * Process:
+     *      1. n := ceil(L / h) (num_iterations)
+     *      2. if n > 2^r - 1, then indicate an error and stop
+     *      3. result(0) = NULL
+     *      4. for i = 1 to n, do
+     *          a. K(i) = PRF(K_I, [i]_2 || Label || 0x00 || Context || [L]_2)
+     *          b. result(i) := result(i - 1) || K(i).
+     *      5. return K_O := the leftmost L bits of result(n).
+     */
+    for (counter = 1; counter <= num_iterations; counter++) {
+        if (counter == num_iterations) {
+            block_size = buffer_length - buffer_offset;
+
+            /* Assumption: if we've validated our arguments correctly, this
+             * should always be true. */
+            PR_ASSERT(block_size <= ctx->mac_size);
+        }
+
+        /* Add all parameters required by this instance of the KDF to the
+         * input stream of the underlying PRF. */
+        ret = kbkdf_AddParameters(CKM_SP800_108_COUNTER_KDF, ctx, params, counter, output_bitlen, NULL, 0 /* chaining_prf output */, 0 /* exclude */);
+        if (ret != CKR_OK) {
+            return ret;
+        }
+
+        /* Finalize this iteration of the PRF. */
+        ret = sftk_MAC_Finish(ctx, ret_buffer + buffer_offset, NULL, block_size);
+        if (ret != CKR_OK) {
+            return ret;
+        }
+
+        /* Increment our position in the key material. */
+        buffer_offset += block_size;
+
+        if (counter < num_iterations) {
+            /* Reset the underlying PRF for the next iteration. Only do this
+             * when we have a next iteration since it isn't necessary to do
+             * either before the first iteration (MAC is already initialized)
+             * or after the last iteration (we won't be called again). */
+            ret = sftk_MAC_Reset(ctx);
+            if (ret != CKR_OK) {
+                return ret;
+            }
+        }
+    }
+
+    return CKR_OK;
+}
+
+static CK_RV
+kbkdf_FeedbackRaw(const CK_SP800_108_KDF_PARAMS *params, const unsigned char *initial_value, CK_ULONG initial_value_length, sftk_MACCtx *ctx, unsigned char *ret_buffer, size_t buffer_length, PRUint64 output_bitlen)
+{
+    CK_RV ret = CKR_OK;
+
+    /* Counter variable for this KDF instance. */
+    PRUint32 counter;
+
+    /* Number of iterations required of this PRF necessary to reach the
+     * desired output length. */
+    PRUint32 num_iterations;
+
+    /* Offset in ret_buffer that we're at. */
+    size_t buffer_offset = 0;
+
+    /* Size of this block, in bytes. Defaults to ctx->mac_size except on
+     * the last iteration where it could be a partial block. */
+    size_t block_size = ctx->mac_size;
+
+    /* The last PRF invocation and/or the initial value; used for feedback
+     * chaining in this KDF. Note that we have to make it large enough to
+     * fit the output of the PRF, but we can delay its actual creation until
+     * the first PRF invocation. Until then, point to the IV value. */
+    unsigned char *chaining_value = (unsigned char *)initial_value;
+
+    /* Size of the chaining value discussed above. Defaults to the size of
+     * the IV value. */
+    size_t chaining_length = initial_value_length;
+
+    /* Calculate the number of iterations required based on the size of the
+     * output buffer. */
+    ret = kbkdf_CalculateIterations(CKM_SP800_108_FEEDBACK_KDF, params, ctx, buffer_length, &num_iterations);
+    if (ret != CKR_OK) {
+        goto finish;
+    }
+
+    /*
+     * 5.2 - [ KDF in Feedback Mode ]
+     *
+     * Fixed values:
+     *      1. h - the length of the PRF in bits (ctx->mac_size)
+     *      2. r - the length of the binary representation of the counter i
+     *          (params[k: params[k].type == CK_SP800_108_OPTIONAL_COUNTER:].data->ulWidthInBits)
+     *          Note that it is only specified when the optional counter is requested.
+     * Input:
+     *      1. K_I - the key for the PRF (base_key)
+     *      2. label - a binary data field, usually before the separator. Optional.
+     *      3. context - a binary data field, usually after the separator. Optional.
+     *      4. IV - a binary data field, initial PRF value. (params->pIV)
+     *      5. L - length of the output in bits (output_bitlen)
+     *
+     * Process:
+     *      1. n := ceil(L / h) (num_iterations)
+     *      2. if n > 2^32 - 1, then indicate an error and stop
+     *      3. result(0) = NULL, K(0) := IV (chaining_value)
+     *      4. for i = 1 to n, do
+     *          a. K(i) = PRF(K_I, K(i-1) {|| [i]_2} || Label || 0x00 || Context || [L]_2)
+     *          b. result(i) := result(i - 1) || K(i).
+     *      5. return K_O := the leftmost L bits of result(n).
+     */
+    for (counter = 1; counter <= num_iterations; counter++) {
+        if (counter == num_iterations) {
+            block_size = buffer_length - buffer_offset;
+
+            /* Assumption: if we've validated our arguments correctly, this
+             * should always be true. */
+            PR_ASSERT(block_size <= ctx->mac_size);
+        }
+
+        /* Add all parameters required by this instance of the KDF to the
+         * input stream of the underlying PRF. */
+        ret = kbkdf_AddParameters(CKM_SP800_108_FEEDBACK_KDF, ctx, params, counter, output_bitlen, chaining_value, chaining_length, 0 /* exclude */);
+        if (ret != CKR_OK) {
+            goto finish;
+        }
+
+        if (counter == 1) {
+            /* On the first iteration, chaining_value points to the IV from
+             * the caller and chaining_length is the length of that IV. We
+             * now need to allocate a buffer of suitable length to store the
+             * MAC output. */
+            chaining_value = PORT_ZNewArray(unsigned char, ctx->mac_size);
+            chaining_length = ctx->mac_size;
+
+            if (chaining_value == NULL) {
+                ret = CKR_HOST_MEMORY;
+                goto finish;
+            }
+        }
+
+        /* Finalize this iteration of the PRF. Unlike other KDF forms, we
+         * first save this to the chaining value so that we can reuse it
+         * in the next iteration before copying the necessary length to
+         * the output buffer. */
+        ret = sftk_MAC_Finish(ctx, chaining_value, NULL, chaining_length);
+        if (ret != CKR_OK) {
+            goto finish;
+        }
+
+        /* Save as much of the chaining value as we need for output. */
+        PORT_Memcpy(ret_buffer + buffer_offset, chaining_value, block_size);
+
+        /* Increment our position in the key material. */
+        buffer_offset += block_size;
+
+        if (counter < num_iterations) {
+            /* Reset the underlying PRF for the next iteration. Only do this
+             * when we have a next iteration since it isn't necessary to do
+             * either before the first iteration (MAC is already initialized)
+             * or after the last iteration (we won't be called again). */
+            ret = sftk_MAC_Reset(ctx);
+            if (ret != CKR_OK) {
+                goto finish;
+            }
+        }
+    }
+
+finish:
+    if (chaining_value != initial_value && chaining_value != NULL) {
+        PORT_ZFree(chaining_value, chaining_length);
+    }
+
+    return ret;
+}
+
+static CK_RV
+kbkdf_PipelineRaw(const CK_SP800_108_KDF_PARAMS *params, sftk_MACCtx *ctx, unsigned char *ret_buffer, size_t buffer_length, PRUint64 output_bitlen)
+{
+    CK_RV ret = CKR_OK;
+
+    /* Counter variable for this KDF instance. */
+    PRUint32 counter;
+
+    /* Number of iterations required of this PRF necessary to reach the
+     * desired output length. */
+    PRUint32 num_iterations;
+
+    /* Offset in ret_buffer that we're at. */
+    size_t buffer_offset = 0;
+
+    /* Size of this block, in bytes. Defaults to ctx->mac_size except on
+     * the last iteration where it could be a partial block. */
+    size_t block_size = ctx->mac_size;
+
+    /* The last PRF invocation. This is used for the first of the double
+     * PRF invocations this KDF is named after. This defaults to NULL,
+     * signifying that we have to calculate the initial value from params;
+     * when non-NULL, we directly add only this value to the PRF. */
+    unsigned char *chaining_value = NULL;
+
+    /* Size of the chaining value discussed above. Defaults to 0. */
+    size_t chaining_length = 0;
+
+    /* Calculate the number of iterations required based on the size of the
+     * output buffer. */
+    ret = kbkdf_CalculateIterations(CKM_SP800_108_DOUBLE_PIPELINE_KDF, params, ctx, buffer_length, &num_iterations);
+    if (ret != CKR_OK) {
+        goto finish;
+    }
+
+    /*
+     * 5.3 - [ KDF in Double-Pipeline Iteration Mode ]
+     *
+     * Fixed values:
+     *      1. h - the length of the PRF in bits (ctx->mac_size)
+     *      2. r - the length of the binary representation of the counter i
+     *          (params[k: params[k].type == CK_SP800_108_OPTIONAL_COUNTER:].data->ulWidthInBits)
+     *          Note that it is only specified when the optional counter is requested.
+     * Input:
+     *      1. K_I - the key for the PRF (base_key)
+     *      2. label - a binary data field, usually before the separator. Optional.
+     *      3. context - a binary data field, usually after the separator. Optional.
+     *      4. L - length of the output in bits (output_bitlen)
+     *
+     * Process:
+     *      1. n := ceil(L / h) (num_iterations)
+     *      2. if n > 2^32 - 1, then indicate an error and stop
+     *      3. result(0) = NULL
+     *      4. A(0) := IV := Label || 0x00 || Context || [L]_2
+     *      5. for i = 1 to n, do
+     *          a. A(i) := PRF(K_I, A(i-1))
+     *          b. K(i) := PRF(K_I, A(i) {|| [i]_2} || Label || 0x00 || Context || [L]_2
+     *          c. result(i) := result(i-1) || K(i)
+     *      6. return K_O := the leftmost L bits of result(n).
+     */
+    for (counter = 1; counter <= num_iterations; counter++) {
+        if (counter == num_iterations) {
+            block_size = buffer_length - buffer_offset;
+
+            /* Assumption: if we've validated our arguments correctly, this
+             * should always be true. */
+            PR_ASSERT(block_size <= ctx->mac_size);
+        }
+
+        /* ===== First pipeline: construct A(i) ===== */
+        if (counter == 1) {
+            /* On the first iteration, we have no chaining value so specify
+             * NULL for the pointer and 0 for the length, and exclude the
+             * optional counter if it exists. This is what NIST specifies as
+             * the IV for the KDF. */
+            ret = kbkdf_AddParameters(CKM_SP800_108_DOUBLE_PIPELINE_KDF, ctx, params, counter, output_bitlen, NULL, 0, CK_SP800_108_OPTIONAL_COUNTER);
+            if (ret != CKR_OK) {
+                goto finish;
+            }
+
+            /* Allocate the chaining value so we can save the PRF output. */
+            chaining_value = PORT_ZNewArray(unsigned char, ctx->mac_size);
+            chaining_length = ctx->mac_size;
+            if (chaining_value == NULL) {
+                ret = CKR_HOST_MEMORY;
+                goto finish;
+            }
+        } else {
+            /* On all other iterations, the next stage of the first pipeline
+             * comes directly from this stage. */
+            ret = sftk_MAC_Update(ctx, chaining_value, chaining_length);
+            if (ret != CKR_OK) {
+                goto finish;
+            }
+        }
+
+        /* Save the PRF output to chaining_value for use in the second
+         * pipeline. */
+        ret = sftk_MAC_Finish(ctx, chaining_value, NULL, chaining_length);
+        if (ret != CKR_OK) {
+            goto finish;
+        }
+
+        /* Reset the PRF so we can reuse it for the second pipeline. */
+        ret = sftk_MAC_Reset(ctx);
+        if (ret != CKR_OK) {
+            goto finish;
+        }
+
+        /* ===== Second pipeline: construct K(i) ===== */
+
+        /* Add all parameters required by this instance of the KDF to the
+         * input stream of the underlying PRF. Note that this includes the
+         * chaining value we calculated from the previous pipeline stage. */
+        ret = kbkdf_AddParameters(CKM_SP800_108_FEEDBACK_KDF, ctx, params, counter, output_bitlen, chaining_value, chaining_length, 0 /* exclude */);
+        if (ret != CKR_OK) {
+            goto finish;
+        }
+
+        /* Finalize this iteration of the PRF directly to the output buffer.
+         * Unlike Feedback mode, this pipeline doesn't influence the previous
+         * stage. */
+        ret = sftk_MAC_Finish(ctx, ret_buffer + buffer_offset, NULL, block_size);
+        if (ret != CKR_OK) {
+            goto finish;
+        }
+
+        /* Increment our position in the key material. */
+        buffer_offset += block_size;
+
+        if (counter < num_iterations) {
+            /* Reset the underlying PRF for the next iteration. Only do this
+             * when we have a next iteration since it isn't necessary to do
+             * either before the first iteration (MAC is already initialized)
+             * or after the last iteration (we won't be called again). */
+            ret = sftk_MAC_Reset(ctx);
+            if (ret != CKR_OK) {
+                goto finish;
+            }
+        }
+    }
+
+finish:
+    PORT_ZFree(chaining_value, chaining_length);
+
+    return ret;
+}
+
+static CK_RV
+kbkdf_RawDispatch(CK_MECHANISM_TYPE mech,
+                  const CK_SP800_108_KDF_PARAMS *kdf_params,
+                  const CK_BYTE *initial_value,
+                  CK_ULONG initial_value_length,
+                  SFTKObject *prf_key, const unsigned char *prf_key_bytes,
+                  unsigned int prf_key_length, unsigned char **out_key_bytes,
+                  size_t *out_key_length, unsigned int *mac_size,
+                  CK_ULONG ret_key_size)
+{
+    CK_RV ret;
+    /* Context for our underlying PRF function.
+     *
+     * Zeroing context required unconditional call of sftk_MAC_Destroy.
+     */
+    sftk_MACCtx ctx = { 0 };
+
+    /* We need one buffers large enough to fit the entire KDF key stream for
+     * all iterations of the PRF. This needs only include to the end of the
+     * last key, so it isn't an even multiple of the PRF output size. */
+    unsigned char *output_buffer = NULL;
+
+    /* Size of the above buffer, in bytes. Note that this is technically
+     * separate from the below output_bitlen variable due to the presence
+     * of additional derived keys. See commentary in kbkdf_CalculateLength.
+     */
+    size_t buffer_length = 0;
+
+    /* While NIST specifies a maximum length (in bits) for the counter, they
+     * don't for the maximum length. It is unlikely, but theoretically
+     * possible for output of the PRF to exceed 32 bits while keeping the
+     * counter under 2^32. Thus, use a 64-bit variable for the maximum
+     * output length.
+     *
+     * It is unlikely any caller will request this much data in practice.
+     * 2^32 invocations of the PRF (for a 512-bit PRF) would be 256GB of
+     * data in the KDF key stream alone. The bigger limit is the number of
+     * and size of keys (again, 2^32); this could easily exceed 256GB when
+     * counting the backing softoken key, the key data, template data, and
+     * the input parameters to this KDF.
+     *
+     * This is the L parameter in NIST SP800-108.
+     */
+    PRUint64 output_bitlen = 0;
+
+    /* First validate our passed input parameters against PKCS#11 v3.0
+     * and NIST SP800-108 requirements. */
+    ret = kbkdf_ValidateParameters(mech, kdf_params, ret_key_size);
+    if (ret != CKR_OK) {
+        goto finish;
+    }
+
+    /* Initialize the underlying PRF state. */
+    if (prf_key) {
+        ret = sftk_MAC_Init(&ctx, kdf_params->prfType, prf_key);
+    } else {
+        ret = sftk_MAC_InitRaw(&ctx, kdf_params->prfType, prf_key_bytes,
+                               prf_key_length, PR_TRUE);
+    }
+    if (ret != CKR_OK) {
+        goto finish;
+    }
+
+    /* Compute the size of our output buffer based on passed parameters and
+     * the output size of the underlying PRF. */
+    ret = kbkdf_CalculateLength(kdf_params, &ctx, ret_key_size, &output_bitlen, &buffer_length);
+    if (ret != CKR_OK) {
+        goto finish;
+    }
+
+    /* Allocate memory for the PRF output */
+    output_buffer = PORT_ZNewArray(unsigned char, buffer_length);
+    if (output_buffer == NULL) {
+        ret = CKR_HOST_MEMORY;
+        goto finish;
+    }
+
+    /* Call into the underlying KDF */
+    switch (mech) {
+        case CKM_NSS_SP800_108_COUNTER_KDF_DERIVE_DATA: /* fall through */
+        case CKM_SP800_108_COUNTER_KDF:
+            ret = kbkdf_CounterRaw(kdf_params, &ctx, output_buffer, buffer_length, output_bitlen);
+            break;
+        case CKM_NSS_SP800_108_FEEDBACK_KDF_DERIVE_DATA: /* fall through */
+        case CKM_SP800_108_FEEDBACK_KDF:
+            ret = kbkdf_FeedbackRaw(kdf_params, initial_value, initial_value_length, &ctx, output_buffer, buffer_length, output_bitlen);
+            break;
+        case CKM_NSS_SP800_108_DOUBLE_PIPELINE_KDF_DERIVE_DATA: /* fall through */
+        case CKM_SP800_108_DOUBLE_PIPELINE_KDF:
+            ret = kbkdf_PipelineRaw(kdf_params, &ctx, output_buffer, buffer_length, output_bitlen);
+            break;
+        default:
+            /* Shouldn't happen unless NIST introduces a new KBKDF type. */
+            PR_ASSERT(PR_FALSE);
+            ret = CKR_FUNCTION_FAILED;
+    }
+
+    /* Validate the above KDF succeeded. */
+    if (ret != CKR_OK) {
+        goto finish;
+    }
+
+    *out_key_bytes = output_buffer;
+    *out_key_length = buffer_length;
+    *mac_size = ctx.mac_size;
+
+    output_buffer = NULL; /* returning the buffer, don't zero and free it */
+
+finish:
+    PORT_ZFree(output_buffer, buffer_length);
+
+    /* Free the PRF. This should handle clearing all sensitive information. */
+    sftk_MAC_Destroy(&ctx, PR_FALSE);
+    return ret;
+}
+
+/* [ section: PKCS#11 entry ] */
+
+CK_RV
+kbkdf_Dispatch(CK_MECHANISM_TYPE mech, CK_SESSION_HANDLE hSession, CK_MECHANISM_PTR pMechanism, SFTKObject *prf_key, SFTKObject *ret_key, CK_ULONG ret_key_size)
+{
+    /* This handles boilerplate common to all KBKDF types. Instead of placing
+     * this in pkcs11c.c, place it here to reduce clutter. */
+
+    CK_RV ret;
+
+    /* Assumptions about our calling environment. */
+    PR_ASSERT(pMechanism != NULL && prf_key != NULL && ret_key != NULL);
+
+    /* Validate that the caller passed parameters. */
+    if (pMechanism->pParameter == NULL) {
+        return CKR_MECHANISM_PARAM_INVALID;
+    }
+
+    /* Create a common set of parameters to use for all KDF types. This
+     * separates out the KDF parameters from the Feedback-specific IV,
+     * allowing us to use a common type for all calls. */
+    CK_SP800_108_KDF_PARAMS kdf_params = { 0 };
+    CK_BYTE_PTR initial_value = NULL;
+    CK_ULONG initial_value_length = 0;
+    unsigned char *output_buffer = NULL;
+    size_t buffer_length = 0;
+    unsigned int mac_size = 0;
+
+    /* Split Feedback-specific IV from remaining KDF parameters. */
+    ret = kbkdf_LoadParameters(mech, pMechanism, &kdf_params, &initial_value, &initial_value_length);
+    if (ret != CKR_OK) {
+        goto finish;
+    }
+    /* let rawDispatch handle the rest. We split this out so we could
+     * handle the POST test without accessing pkcs #11 objects. */
+    ret = kbkdf_RawDispatch(mech, &kdf_params, initial_value,
+                            initial_value_length, prf_key, NULL, 0,
+                            &output_buffer, &buffer_length, &mac_size,
+                            ret_key_size);
+    if (ret != CKR_OK) {
+        goto finish;
+    }
+
+    /* Write the output of the PRF into the appropriate keys. */
+    ret = kbkdf_SaveKeys(mech, hSession, &kdf_params, output_buffer, buffer_length, mac_size, ret_key, ret_key_size);
+    if (ret != CKR_OK) {
+        goto finish;
+    }
+
+finish:
+    PORT_ZFree(output_buffer, buffer_length);
+
+    return ret;
+}
+
+struct sftk_SP800_Test_struct {
+    CK_MECHANISM_TYPE mech;
+    CK_SP800_108_KDF_PARAMS kdf_params;
+    unsigned int expected_mac_size;
+    unsigned int ret_key_length;
+    const unsigned char expected_key_bytes[64];
+};
+
+static const CK_SP800_108_COUNTER_FORMAT counter_32 = { 0, 32 };
+static const CK_PRF_DATA_PARAM counter_32_data = { CK_SP800_108_ITERATION_VARIABLE, (CK_VOID_PTR)&counter_32, sizeof(counter_32) };
+
+#ifdef NSS_FULL_POST
+static const CK_SP800_108_COUNTER_FORMAT counter_16 = { 0, 16 };
+static const CK_PRF_DATA_PARAM counter_16_data = { CK_SP800_108_ITERATION_VARIABLE, (CK_VOID_PTR)&counter_16, sizeof(counter_16) };
+static const CK_PRF_DATA_PARAM counter_null_data = { CK_SP800_108_ITERATION_VARIABLE, NULL, 0 };
+#endif
+
+static const struct sftk_SP800_Test_struct sftk_SP800_Tests[] = {
+#ifdef NSS_FULL_POST
+    {
+        CKM_SP800_108_COUNTER_KDF,
+        { CKM_AES_CMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_16_data, 0, NULL },
+        16,
+        64,
+        { 0x7b, 0x1c, 0xe7, 0xf3, 0x14, 0x67, 0x15, 0xdd,
+          0xde, 0x0c, 0x09, 0x46, 0x3f, 0x47, 0x7b, 0xa6,
+          0xb8, 0xba, 0x40, 0x07, 0x7c, 0xe3, 0x19, 0x53,
+          0x26, 0xac, 0x4c, 0x2e, 0x2b, 0x37, 0x41, 0xe4,
+          0x1b, 0x01, 0x3f, 0x2f, 0x2d, 0x16, 0x95, 0xee,
+          0xeb, 0x7e, 0x72, 0x7d, 0xa4, 0xab, 0x2e, 0x67,
+          0x1d, 0xef, 0x6f, 0xa2, 0xc6, 0xee, 0x3c, 0xcf,
+          0xef, 0x88, 0xfd, 0x5c, 0x1d, 0x7b, 0xa0, 0x5a },
+    },
+    {
+        CKM_SP800_108_COUNTER_KDF,
+        { CKM_SHA384_HMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_32_data, 0, NULL },
+        48,
+        64,
+        { 0xe6, 0x62, 0xa4, 0x32, 0x5c, 0xe4, 0xc2, 0x28,
+          0x73, 0x8a, 0x5d, 0x94, 0xe7, 0x05, 0xe0, 0x5a,
+          0x71, 0x61, 0xb2, 0x3c, 0x51, 0x28, 0x03, 0x1d,
+          0xa7, 0xf5, 0x10, 0x83, 0x34, 0xdb, 0x11, 0x73,
+          0x92, 0xa6, 0x79, 0x74, 0x81, 0x5d, 0x22, 0x7e,
+          0x8d, 0xf2, 0x59, 0x14, 0x56, 0x60, 0xcf, 0xb2,
+          0xb3, 0xfd, 0x46, 0xfd, 0x9b, 0x74, 0xfe, 0x4a,
+          0x09, 0x30, 0x4a, 0xdf, 0x07, 0x43, 0xfe, 0x85 },
+    },
+    {
+        CKM_SP800_108_COUNTER_KDF,
+        { CKM_SHA512_HMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_32_data, 0, NULL },
+        64,
+        64,
+        { 0xb0, 0x78, 0x36, 0xe1, 0x15, 0xd6, 0xf0, 0xac,
+          0x68, 0x7b, 0x42, 0xd3, 0xb6, 0x82, 0x51, 0xad,
+          0x95, 0x0a, 0x69, 0x88, 0x84, 0xc2, 0x2e, 0x07,
+          0x34, 0x62, 0x8d, 0x42, 0x72, 0x0f, 0x22, 0xe6,
+          0xd5, 0x7f, 0x80, 0x15, 0xe6, 0x84, 0x00, 0x65,
+          0xef, 0x64, 0x77, 0x29, 0xd6, 0x3b, 0xc7, 0x9a,
+          0x15, 0x6d, 0x36, 0xf3, 0x96, 0xc9, 0x14, 0x3f,
+          0x2d, 0x4a, 0x7c, 0xdb, 0xc3, 0x6c, 0x3d, 0x6a },
+    },
+    {
+        CKM_SP800_108_FEEDBACK_KDF,
+        { CKM_AES_CMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_null_data, 0, NULL },
+        16,
+        64,
+        { 0xc0, 0xa0, 0x23, 0x96, 0x16, 0x4d, 0xd6, 0xbd,
+          0x2a, 0x75, 0x8e, 0x72, 0xf5, 0xc3, 0xa0, 0xb8,
+          0x78, 0x83, 0x15, 0x21, 0x34, 0xd3, 0xd8, 0x71,
+          0xc9, 0xe7, 0x4b, 0x20, 0xb7, 0x65, 0x5b, 0x13,
+          0xbc, 0x85, 0x54, 0xe3, 0xb6, 0xee, 0x73, 0xd5,
+          0xf2, 0xa0, 0x94, 0x1a, 0x79, 0x66, 0x3b, 0x1e,
+          0x67, 0x3e, 0x69, 0xa4, 0x12, 0x40, 0xa9, 0xda,
+          0x8d, 0x14, 0xb1, 0xce, 0xf1, 0x4b, 0x79, 0x4e },
+    },
+    {
+        CKM_SP800_108_FEEDBACK_KDF,
+        { CKM_SHA256_HMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_null_data, 0, NULL },
+        32,
+        64,
+        { 0x99, 0x9b, 0x08, 0x79, 0x14, 0x2e, 0x58, 0x34,
+          0xd7, 0x92, 0xa7, 0x7e, 0x7f, 0xc2, 0xf0, 0x34,
+          0xa3, 0x4e, 0x33, 0xf0, 0x63, 0x95, 0x2d, 0xad,
+          0xbf, 0x3b, 0xcb, 0x6d, 0x4e, 0x07, 0xd9, 0xe9,
+          0xbd, 0xbd, 0x77, 0x54, 0xe1, 0xa3, 0x36, 0x26,
+          0xcd, 0xb1, 0xf9, 0x2d, 0x80, 0x68, 0xa2, 0x01,
+          0x4e, 0xbf, 0x35, 0xec, 0x65, 0xae, 0xfd, 0x71,
+          0xa6, 0xd7, 0x62, 0x26, 0x2c, 0x3f, 0x73, 0x63 },
+    },
+    {
+        CKM_SP800_108_FEEDBACK_KDF,
+        { CKM_SHA384_HMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_null_data, 0, NULL },
+        48,
+        64,
+        { 0xc8, 0x7a, 0xf8, 0xd9, 0x6b, 0x90, 0x82, 0x35,
+          0xea, 0xf5, 0x2c, 0x8f, 0xce, 0xaa, 0x3b, 0xa5,
+          0x68, 0xd3, 0x7f, 0xae, 0x31, 0x93, 0xe6, 0x69,
+          0x0c, 0xd1, 0x74, 0x7f, 0x8f, 0xc2, 0xe2, 0x33,
+          0x93, 0x45, 0x23, 0xba, 0xb3, 0x73, 0xc9, 0x2c,
+          0xd6, 0xd2, 0x10, 0x16, 0xe9, 0x9f, 0x9e, 0xe8,
+          0xc1, 0x0e, 0x29, 0x95, 0x3d, 0x16, 0x68, 0x24,
+          0x40, 0x4d, 0x40, 0x21, 0x41, 0xa6, 0xc8, 0xdb },
+    },
+    {
+        CKM_SP800_108_FEEDBACK_KDF,
+        { CKM_SHA512_HMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_null_data, 0, NULL },
+        64,
+        64,
+        { 0x81, 0x39, 0x12, 0xc2, 0xf9, 0x31, 0x24, 0x7c,
+          0x71, 0x12, 0x97, 0x08, 0x82, 0x76, 0x83, 0x55,
+          0x8c, 0x82, 0xf3, 0x09, 0xd6, 0x1b, 0x7a, 0xa2,
+          0x6e, 0x71, 0x6b, 0xad, 0x46, 0x57, 0x60, 0x89,
+          0x38, 0xcf, 0x63, 0xfa, 0xf4, 0x38, 0x27, 0xef,
+          0xf0, 0xaf, 0x75, 0x4e, 0xc2, 0xe0, 0x31, 0xdb,
+          0x59, 0x7d, 0x19, 0xc9, 0x6d, 0xbb, 0xed, 0x95,
+          0xaf, 0x3e, 0xd8, 0x33, 0x76, 0xab, 0xec, 0xfa },
+    },
+    {
+        CKM_SP800_108_DOUBLE_PIPELINE_KDF,
+        { CKM_AES_CMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_null_data, 0, NULL },
+        16,
+        64,
+        { 0x3e, 0xa8, 0xbf, 0x77, 0x84, 0x90, 0xb0, 0x3a,
+          0x89, 0x16, 0x32, 0x01, 0x92, 0xd3, 0x1f, 0x1b,
+          0xc1, 0x06, 0xc5, 0x32, 0x62, 0x03, 0x50, 0x16,
+          0x3b, 0xb9, 0xa7, 0xdc, 0xb5, 0x68, 0x6a, 0xbb,
+          0xbb, 0x7d, 0x63, 0x69, 0x24, 0x6e, 0x09, 0xd6,
+          0x6f, 0x80, 0x57, 0x65, 0xc5, 0x62, 0x33, 0x96,
+          0x69, 0xe6, 0xab, 0x65, 0x36, 0xd0, 0xe2, 0x5c,
+          0xd7, 0xbd, 0xe4, 0x68, 0x13, 0xd6, 0xb1, 0x46 },
+    },
+    {
+        CKM_SP800_108_DOUBLE_PIPELINE_KDF,
+        { CKM_SHA256_HMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_null_data, 0, NULL },
+        32,
+        64,
+        { 0xeb, 0x28, 0xd9, 0x2c, 0x19, 0x33, 0xb9, 0x2a,
+          0xf9, 0xac, 0x85, 0xbd, 0xf4, 0xdb, 0xfa, 0x88,
+          0x73, 0xf4, 0x36, 0x08, 0xdb, 0xfe, 0x13, 0xd1,
+          0x5a, 0xec, 0x7b, 0x68, 0x13, 0x53, 0xb3, 0xd1,
+          0x31, 0xf2, 0x83, 0xae, 0x9f, 0x75, 0x47, 0xb6,
+          0x6d, 0x3c, 0x20, 0x16, 0x47, 0x9c, 0x27, 0x66,
+          0xec, 0xa9, 0xdf, 0x0c, 0xda, 0x2a, 0xf9, 0xf4,
+          0x55, 0x74, 0xde, 0x9d, 0x3f, 0xe3, 0x5e, 0x14 },
+    },
+    {
+        CKM_SP800_108_DOUBLE_PIPELINE_KDF,
+        { CKM_SHA384_HMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_null_data, 0, NULL },
+        48,
+        64,
+        { 0xa5, 0xca, 0x32, 0x40, 0x00, 0x93, 0xb2, 0xcc,
+          0x78, 0x3c, 0xa6, 0xc4, 0xaf, 0xa8, 0xb3, 0xd0,
+          0xa4, 0x6b, 0xb5, 0x31, 0x35, 0x87, 0x33, 0xa2,
+          0x6a, 0x6b, 0xe1, 0xff, 0xea, 0x1d, 0x6e, 0x9e,
+          0x0b, 0xde, 0x8b, 0x92, 0x15, 0xd6, 0x56, 0x2f,
+          0xb6, 0x1a, 0xd7, 0xd2, 0x01, 0x3e, 0x28, 0x2e,
+          0xfa, 0x84, 0x3c, 0xc0, 0xe8, 0xbe, 0x94, 0xc0,
+          0x06, 0xbd, 0xbf, 0x87, 0x1f, 0xb8, 0x64, 0xc2 },
+    },
+    {
+        CKM_SP800_108_DOUBLE_PIPELINE_KDF,
+        { CKM_SHA512_HMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_null_data, 0, NULL },
+        64,
+        64,
+        { 0x3f, 0xd9, 0x4e, 0x80, 0x58, 0x21, 0xc8, 0xea,
+          0x22, 0x17, 0xcf, 0x7d, 0xce, 0xfd, 0xec, 0x03,
+          0xb9, 0xe4, 0xa2, 0xf7, 0xc0, 0xf1, 0x68, 0x81,
+          0x53, 0x71, 0xb7, 0x42, 0x14, 0x4e, 0x5b, 0x09,
+          0x05, 0x31, 0xb9, 0x27, 0x18, 0x2d, 0x23, 0xf8,
+          0x9c, 0x3d, 0x4e, 0xd0, 0xdd, 0xf3, 0x1e, 0x4b,
+          0xf2, 0xf9, 0x1a, 0x5d, 0x00, 0x66, 0x22, 0x83,
+          0xae, 0x3c, 0x53, 0xd2, 0x54, 0x4b, 0x06, 0x4c },
+    },
+#endif
+    {
+        CKM_SP800_108_COUNTER_KDF,
+        { CKM_SHA256_HMAC, 1, (CK_PRF_DATA_PARAM_PTR)&counter_32_data, 0, NULL },
+        32,
+        64,
+        { 0xfb, 0x2b, 0xb5, 0xde, 0xce, 0x5a, 0x2b, 0xdc,
+          0x25, 0x8f, 0x54, 0x17, 0x4b, 0x5a, 0xa7, 0x90,
+          0x64, 0x36, 0xeb, 0x43, 0x1f, 0x1d, 0xf9, 0x23,
+          0xb2, 0x22, 0x29, 0xa0, 0xfa, 0x2e, 0x21, 0xb6,
+          0xb7, 0xfb, 0x27, 0x0a, 0x1c, 0xa6, 0x58, 0x43,
+          0xa1, 0x16, 0x44, 0x29, 0x4b, 0x1c, 0xb3, 0x72,
+          0xd5, 0x98, 0x9d, 0x27, 0xd5, 0x75, 0x25, 0xbf,
+          0x23, 0x61, 0x40, 0x48, 0xbb, 0x0b, 0x49, 0x8e },
+    }
+};
+
+SECStatus
+sftk_fips_SP800_108_PowerUpSelfTests(void)
+{
+    int i;
+    CK_RV crv;
+
+    const unsigned char prf_key[] = {
+        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
+        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18,
+        0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28,
+        0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38,
+        0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
+        0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
+        0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
+        0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78
+    };
+    for (i = 0; i < PR_ARRAY_SIZE(sftk_SP800_Tests); i++) {
+        const struct sftk_SP800_Test_struct *test = &sftk_SP800_Tests[i];
+        unsigned char *output_buffer;
+        size_t buffer_length;
+        unsigned int mac_size;
+
+        crv = kbkdf_RawDispatch(test->mech, &test->kdf_params,
+                                prf_key, test->expected_mac_size,
+                                NULL, prf_key, test->expected_mac_size,
+                                &output_buffer, &buffer_length, &mac_size,
+                                test->ret_key_length);
+        if (crv != CKR_OK) {
+            PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
+            return SECFailure;
+        }
+        if ((mac_size != test->expected_mac_size) ||
+            (buffer_length != test->ret_key_length) ||
+            (output_buffer == NULL) ||
+            (PORT_Memcmp(output_buffer, test->expected_key_bytes, buffer_length) != 0)) {
+            PORT_ZFree(output_buffer, buffer_length);
+            return SECFailure;
+        }
+        PORT_ZFree(output_buffer, buffer_length);
+    }
+    return SECSuccess;
+}