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-rw-r--r--security/nss/lib/pk11wrap/pk11sdr.c437
1 files changed, 437 insertions, 0 deletions
diff --git a/security/nss/lib/pk11wrap/pk11sdr.c b/security/nss/lib/pk11wrap/pk11sdr.c
new file mode 100644
index 0000000000..eb67bfba82
--- /dev/null
+++ b/security/nss/lib/pk11wrap/pk11sdr.c
@@ -0,0 +1,437 @@
+/* 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 "seccomon.h"
+#include "secoid.h"
+#include "secasn1.h"
+#include "pkcs11.h"
+#include "pk11func.h"
+#include "pk11sdr.h"
+
+/*
+ * Data structure and template for encoding the result of an SDR operation
+ * This is temporary. It should include the algorithm ID of the encryption mechanism
+ */
+struct SDRResult {
+ SECItem keyid;
+ SECAlgorithmID alg;
+ SECItem data;
+};
+typedef struct SDRResult SDRResult;
+
+SEC_ASN1_MKSUB(SECOID_AlgorithmIDTemplate)
+
+static SEC_ASN1Template template[] = {
+ { SEC_ASN1_SEQUENCE, 0, NULL, sizeof(SDRResult) },
+ { SEC_ASN1_OCTET_STRING, offsetof(SDRResult, keyid) },
+ { SEC_ASN1_INLINE | SEC_ASN1_XTRN, offsetof(SDRResult, alg),
+ SEC_ASN1_SUB(SECOID_AlgorithmIDTemplate) },
+ { SEC_ASN1_OCTET_STRING, offsetof(SDRResult, data) },
+ { 0 }
+};
+
+static unsigned char keyID[] = {
+ 0xF8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01
+};
+
+static SECItem keyIDItem = {
+ 0,
+ keyID,
+ sizeof keyID
+};
+
+/* local utility function for padding an incoming data block
+ * to the mechanism block size.
+ */
+static SECStatus
+padBlock(SECItem *data, int blockSize, SECItem *result)
+{
+ SECStatus rv = SECSuccess;
+ int padLength;
+ unsigned int i;
+
+ result->data = 0;
+ result->len = 0;
+
+ /* This algorithm always adds to the block (to indicate the number
+ * of pad bytes). So allocate a block large enough.
+ */
+ padLength = blockSize - (data->len % blockSize);
+ result->len = data->len + padLength;
+ result->data = (unsigned char *)PORT_Alloc(result->len);
+
+ /* Copy the data */
+ PORT_Memcpy(result->data, data->data, data->len);
+
+ /* Add the pad values */
+ for (i = data->len; i < result->len; i++)
+ result->data[i] = (unsigned char)padLength;
+
+ return rv;
+}
+
+static SECStatus
+unpadBlock(SECItem *data, int blockSize, SECItem *result)
+{
+ SECStatus rv = SECSuccess;
+ int padLength;
+ unsigned int i;
+
+ result->data = 0;
+ result->len = 0;
+
+ /* Remove the padding from the end if the input data */
+ if (data->len == 0 || data->len % blockSize != 0) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ padLength = data->data[data->len - 1];
+ if (padLength > blockSize) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ /* verify padding */
+ for (i = data->len - padLength; i < data->len; i++) {
+ if (data->data[i] != padLength) {
+ rv = SECFailure;
+ goto loser;
+ }
+ }
+
+ result->len = data->len - padLength;
+ result->data = (unsigned char *)PORT_Alloc(result->len);
+ if (!result->data) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ PORT_Memcpy(result->data, data->data, result->len);
+
+ if (padLength < 2) {
+ return SECWouldBlock;
+ }
+
+loser:
+ return rv;
+}
+
+static PRLock *pk11sdrLock = NULL;
+
+void
+pk11sdr_Init(void)
+{
+ pk11sdrLock = PR_NewLock();
+}
+
+void
+pk11sdr_Shutdown(void)
+{
+ if (pk11sdrLock) {
+ PR_DestroyLock(pk11sdrLock);
+ pk11sdrLock = NULL;
+ }
+}
+
+/*
+ * PK11SDR_Encrypt
+ * Encrypt a block of data using the symmetric key identified. The result
+ * is an ASN.1 (DER) encoded block of keyid, params and data.
+ */
+SECStatus
+PK11SDR_Encrypt(SECItem *keyid, SECItem *data, SECItem *result, void *cx)
+{
+ SECStatus rv = SECSuccess;
+ PK11SlotInfo *slot = 0;
+ PK11SymKey *key = 0;
+ SECItem *params = 0;
+ PK11Context *ctx = 0;
+ CK_MECHANISM_TYPE type;
+ SDRResult sdrResult;
+ SECItem paddedData;
+ SECItem *pKeyID;
+ PLArenaPool *arena = 0;
+
+ /* Initialize */
+ paddedData.len = 0;
+ paddedData.data = 0;
+
+ arena = PORT_NewArena(SEC_ASN1_DEFAULT_ARENA_SIZE);
+ if (!arena) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ /* 1. Locate the requested keyid, or the default key (which has a keyid)
+ * 2. Create an encryption context
+ * 3. Encrypt
+ * 4. Encode the results (using ASN.1)
+ */
+
+ slot = PK11_GetInternalKeySlot();
+ if (!slot) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ /* Use triple-DES */
+ type = CKM_DES3_CBC;
+
+ /*
+ * Login to the internal token before we look for the key, otherwise we
+ * won't find it.
+ */
+ rv = PK11_Authenticate(slot, PR_TRUE, cx);
+ if (rv != SECSuccess)
+ goto loser;
+
+ /* Find the key to use */
+ pKeyID = keyid;
+ if (pKeyID->len == 0) {
+ pKeyID = &keyIDItem; /* Use default value */
+
+ /* put in a course lock to prevent a race between not finding the
+ * key and creating one.
+ */
+
+ if (pk11sdrLock)
+ PR_Lock(pk11sdrLock);
+
+ /* Try to find the key */
+ key = PK11_FindFixedKey(slot, type, pKeyID, cx);
+
+ /* If the default key doesn't exist yet, try to create it */
+ if (!key)
+ key = PK11_GenDES3TokenKey(slot, pKeyID, cx);
+ if (pk11sdrLock)
+ PR_Unlock(pk11sdrLock);
+ } else {
+ key = PK11_FindFixedKey(slot, type, pKeyID, cx);
+ }
+
+ if (!key) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ params = PK11_GenerateNewParam(type, key);
+ if (!params) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ ctx = PK11_CreateContextBySymKey(type, CKA_ENCRYPT, key, params);
+ if (!ctx) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ rv = padBlock(data, PK11_GetBlockSize(type, 0), &paddedData);
+ if (rv != SECSuccess)
+ goto loser;
+
+ sdrResult.data.len = paddedData.len;
+ sdrResult.data.data = (unsigned char *)PORT_ArenaAlloc(arena, sdrResult.data.len);
+
+ rv = PK11_CipherOp(ctx, sdrResult.data.data, (int *)&sdrResult.data.len, sdrResult.data.len,
+ paddedData.data, paddedData.len);
+ if (rv != SECSuccess)
+ goto loser;
+
+ PK11_Finalize(ctx);
+
+ sdrResult.keyid = *pKeyID;
+
+ rv = PK11_ParamToAlgid(SEC_OID_DES_EDE3_CBC, params, arena, &sdrResult.alg);
+ if (rv != SECSuccess)
+ goto loser;
+
+ if (!SEC_ASN1EncodeItem(0, result, &sdrResult, template)) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+loser:
+ SECITEM_ZfreeItem(&paddedData, PR_FALSE);
+ if (arena)
+ PORT_FreeArena(arena, PR_TRUE);
+ if (ctx)
+ PK11_DestroyContext(ctx, PR_TRUE);
+ if (params)
+ SECITEM_ZfreeItem(params, PR_TRUE);
+ if (key)
+ PK11_FreeSymKey(key);
+ if (slot)
+ PK11_FreeSlot(slot);
+
+ return rv;
+}
+
+/* decrypt a block */
+static SECStatus
+pk11Decrypt(PK11SlotInfo *slot, PLArenaPool *arena,
+ CK_MECHANISM_TYPE type, PK11SymKey *key,
+ SECItem *params, SECItem *in, SECItem *result)
+{
+ PK11Context *ctx = 0;
+ SECItem paddedResult;
+ SECStatus rv;
+
+ paddedResult.len = 0;
+ paddedResult.data = 0;
+
+ ctx = PK11_CreateContextBySymKey(type, CKA_DECRYPT, key, params);
+ if (!ctx) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ paddedResult.len = in->len;
+ paddedResult.data = PORT_ArenaAlloc(arena, paddedResult.len);
+
+ rv = PK11_CipherOp(ctx, paddedResult.data,
+ (int *)&paddedResult.len, paddedResult.len,
+ in->data, in->len);
+ if (rv != SECSuccess)
+ goto loser;
+
+ PK11_Finalize(ctx);
+
+ /* Remove the padding */
+ rv = unpadBlock(&paddedResult, PK11_GetBlockSize(type, 0), result);
+ if (rv)
+ goto loser;
+
+loser:
+ if (ctx)
+ PK11_DestroyContext(ctx, PR_TRUE);
+ return rv;
+}
+
+/*
+ * PK11SDR_Decrypt
+ * Decrypt a block of data produced by PK11SDR_Encrypt. The key used is identified
+ * by the keyid field within the input.
+ */
+SECStatus
+PK11SDR_Decrypt(SECItem *data, SECItem *result, void *cx)
+{
+ SECStatus rv = SECSuccess;
+ PK11SlotInfo *slot = 0;
+ PK11SymKey *key = 0;
+ CK_MECHANISM_TYPE type;
+ SDRResult sdrResult;
+ SECItem *params = 0;
+ SECItem possibleResult = { 0, NULL, 0 };
+ PLArenaPool *arena = 0;
+
+ arena = PORT_NewArena(SEC_ASN1_DEFAULT_ARENA_SIZE);
+ if (!arena) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ /* Decode the incoming data */
+ memset(&sdrResult, 0, sizeof sdrResult);
+ rv = SEC_QuickDERDecodeItem(arena, &sdrResult, template, data);
+ if (rv != SECSuccess)
+ goto loser; /* Invalid format */
+
+ /* Find the slot and key for the given keyid */
+ slot = PK11_GetInternalKeySlot();
+ if (!slot) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ rv = PK11_Authenticate(slot, PR_TRUE, cx);
+ if (rv != SECSuccess)
+ goto loser;
+
+ /* Get the parameter values from the data */
+ params = PK11_ParamFromAlgid(&sdrResult.alg);
+ if (!params) {
+ rv = SECFailure;
+ goto loser;
+ }
+
+ /* Use triple-DES (Should look up the algorithm) */
+ type = CKM_DES3_CBC;
+ key = PK11_FindFixedKey(slot, type, &sdrResult.keyid, cx);
+ if (!key) {
+ rv = SECFailure;
+ } else {
+ rv = pk11Decrypt(slot, arena, type, key, params,
+ &sdrResult.data, result);
+ }
+
+ /*
+ * if the pad value was too small (1 or 2), then it's statistically
+ * 'likely' that (1 in 256) that we may not have the correct key.
+ * Check the other keys for a better match. If we find none, use
+ * this result.
+ */
+ if (rv == SECWouldBlock) {
+ possibleResult = *result;
+ }
+
+ /*
+ * handle the case where your key indicies may have been broken
+ */
+ if (rv != SECSuccess) {
+ PK11SymKey *keyList = PK11_ListFixedKeysInSlot(slot, NULL, cx);
+ PK11SymKey *testKey = NULL;
+ PK11SymKey *nextKey = NULL;
+
+ for (testKey = keyList; testKey;
+ testKey = PK11_GetNextSymKey(testKey)) {
+ rv = pk11Decrypt(slot, arena, type, testKey, params,
+ &sdrResult.data, result);
+ if (rv == SECSuccess) {
+ break;
+ }
+ /* found a close match. If it's our first remember it */
+ if (rv == SECWouldBlock) {
+ if (possibleResult.data) {
+ /* this is unlikely but possible. If we hit this condition,
+ * we have no way of knowing which possibility to prefer.
+ * in this case we just match the key the application
+ * thought was the right one */
+ SECITEM_ZfreeItem(result, PR_FALSE);
+ } else {
+ possibleResult = *result;
+ }
+ }
+ }
+
+ /* free the list */
+ for (testKey = keyList; testKey; testKey = nextKey) {
+ nextKey = PK11_GetNextSymKey(testKey);
+ PK11_FreeSymKey(testKey);
+ }
+ }
+
+ /* we didn't find a better key, use the one with a small pad value */
+ if ((rv != SECSuccess) && (possibleResult.data)) {
+ *result = possibleResult;
+ possibleResult.data = NULL;
+ rv = SECSuccess;
+ }
+
+loser:
+ if (arena)
+ PORT_FreeArena(arena, PR_TRUE);
+ if (key)
+ PK11_FreeSymKey(key);
+ if (params)
+ SECITEM_ZfreeItem(params, PR_TRUE);
+ if (slot)
+ PK11_FreeSlot(slot);
+ if (possibleResult.data)
+ SECITEM_ZfreeItem(&possibleResult, PR_FALSE);
+
+ return rv;
+}