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-rw-r--r--nss/cmd/lib/berparse.c388
1 files changed, 388 insertions, 0 deletions
diff --git a/nss/cmd/lib/berparse.c b/nss/cmd/lib/berparse.c
new file mode 100644
index 0000000..8cd1eba
--- /dev/null
+++ b/nss/cmd/lib/berparse.c
@@ -0,0 +1,388 @@
+/* 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 "secutil.h"
+
+typedef enum {
+ tagDone,
+ lengthDone,
+ leafDone,
+ compositeDone,
+ notDone,
+ parseError,
+ parseComplete
+} ParseState;
+
+typedef unsigned char Byte;
+typedef void (*ParseProc)(BERParse *h, unsigned char **buf, int *len);
+typedef struct {
+ SECArb arb;
+ int pos; /* length from global start to item start */
+ SECArb *parent;
+} ParseStackElem;
+
+struct BERParseStr {
+ PLArenaPool *his;
+ PLArenaPool *mine;
+ ParseProc proc;
+ int stackDepth;
+ ParseStackElem *stackPtr;
+ ParseStackElem *stack;
+ int pending; /* bytes remaining to complete this part */
+ int pos; /* running length of consumed characters */
+ ParseState state;
+ PRBool keepLeaves;
+ PRBool derOnly;
+ BERFilterProc filter;
+ void *filterArg;
+ BERNotifyProc before;
+ void *beforeArg;
+ BERNotifyProc after;
+ void *afterArg;
+};
+
+#define UNKNOWN -1
+
+static unsigned char
+NextChar(BERParse *h, unsigned char **buf, int *len)
+{
+ unsigned char c = *(*buf)++;
+ (*len)--;
+ h->pos++;
+ if (h->filter)
+ (*h->filter)(h->filterArg, &c, 1);
+ return c;
+}
+
+static void
+ParseTag(BERParse *h, unsigned char **buf, int *len)
+{
+ SECArb *arb = &(h->stackPtr->arb);
+ arb->tag = NextChar(h, buf, len);
+
+ PORT_Assert(h->state == notDone);
+
+ /*
+ * NOTE: This does not handle the high-tag-number form
+ */
+ if ((arb->tag & DER_HIGH_TAG_NUMBER) == DER_HIGH_TAG_NUMBER) {
+ PORT_SetError(SEC_ERROR_BAD_DER);
+ h->state = parseError;
+ return;
+ }
+
+ h->pending = UNKNOWN;
+ arb->length = UNKNOWN;
+ if (arb->tag & DER_CONSTRUCTED) {
+ arb->body.cons.numSubs = 0;
+ arb->body.cons.subs = NULL;
+ } else {
+ arb->body.item.len = UNKNOWN;
+ arb->body.item.data = NULL;
+ }
+
+ h->state = tagDone;
+}
+
+static void
+ParseLength(BERParse *h, unsigned char **buf, int *len)
+{
+ Byte b;
+ SECArb *arb = &(h->stackPtr->arb);
+
+ PORT_Assert(h->state == notDone);
+
+ if (h->pending == UNKNOWN) {
+ b = NextChar(h, buf, len);
+ if ((b & 0x80) == 0) { /* short form */
+ arb->length = b;
+ /*
+ * if the tag and the length are both zero bytes, then this
+ * should be the marker showing end of list for the
+ * indefinite length composite
+ */
+ if (arb->length == 0 && arb->tag == 0)
+ h->state = compositeDone;
+ else
+ h->state = lengthDone;
+ return;
+ }
+
+ h->pending = b & 0x7f;
+ /* 0 implies this is an indefinite length */
+ if (h->pending > 4) {
+ PORT_SetError(SEC_ERROR_BAD_DER);
+ h->state = parseError;
+ return;
+ }
+ arb->length = 0;
+ }
+
+ while ((*len > 0) && (h->pending > 0)) {
+ b = NextChar(h, buf, len);
+ arb->length = (arb->length << 8) + b;
+ h->pending--;
+ }
+ if (h->pending == 0) {
+ if (h->derOnly && (arb->length == 0))
+ h->state = parseError;
+ else
+ h->state = lengthDone;
+ }
+ return;
+}
+
+static void
+ParseLeaf(BERParse *h, unsigned char **buf, int *len)
+{
+ int count;
+ SECArb *arb = &(h->stackPtr->arb);
+
+ PORT_Assert(h->state == notDone);
+ PORT_Assert(h->pending >= 0);
+
+ if (*len < h->pending)
+ count = *len;
+ else
+ count = h->pending;
+
+ if (h->keepLeaves)
+ memcpy(arb->body.item.data + arb->body.item.len, *buf, count);
+ if (h->filter)
+ (*h->filter)(h->filterArg, *buf, count);
+ *buf += count;
+ *len -= count;
+ arb->body.item.len += count;
+ h->pending -= count;
+ h->pos += count;
+ if (h->pending == 0) {
+ h->state = leafDone;
+ }
+ return;
+}
+
+static void
+CreateArbNode(BERParse *h)
+{
+ SECArb *arb = PORT_ArenaAlloc(h->his, sizeof(SECArb));
+
+ *arb = h->stackPtr->arb;
+
+ /*
+ * Special case closing the root
+ */
+ if (h->stackPtr == h->stack) {
+ PORT_Assert(arb->tag & DER_CONSTRUCTED);
+ h->state = parseComplete;
+ } else {
+ SECArb *parent = h->stackPtr->parent;
+ parent->body.cons.subs = DS_ArenaGrow(
+ h->his, parent->body.cons.subs,
+ (parent->body.cons.numSubs) * sizeof(SECArb *),
+ (parent->body.cons.numSubs + 1) * sizeof(SECArb *));
+ parent->body.cons.subs[parent->body.cons.numSubs] = arb;
+ parent->body.cons.numSubs++;
+ h->proc = ParseTag;
+ h->state = notDone;
+ h->pending = UNKNOWN;
+ }
+ if (h->after)
+ (*h->after)(h->afterArg, arb, h->stackPtr - h->stack, PR_FALSE);
+}
+
+SECStatus
+BER_ParseSome(BERParse *h, unsigned char *buf, int len)
+{
+ if (h->state == parseError)
+ return PR_TRUE;
+
+ while (len) {
+ (*h->proc)(h, &buf, &len);
+ if (h->state == parseComplete) {
+ PORT_SetError(SEC_ERROR_BAD_DER);
+ h->state = parseError;
+ return PR_TRUE;
+ }
+ if (h->state == parseError)
+ return PR_TRUE;
+ PORT_Assert(h->state != parseComplete);
+
+ if (h->state <= compositeDone) {
+ if (h->proc == ParseTag) {
+ PORT_Assert(h->state == tagDone);
+ h->proc = ParseLength;
+ h->state = notDone;
+ } else if (h->proc == ParseLength) {
+ SECArb *arb = &(h->stackPtr->arb);
+ PORT_Assert(h->state == lengthDone || h->state == compositeDone);
+
+ if (h->before)
+ (*h->before)(h->beforeArg, arb,
+ h->stackPtr - h->stack, PR_TRUE);
+
+ /*
+ * Check to see if this is the end of an indefinite
+ * length composite
+ */
+ if (h->state == compositeDone) {
+ SECArb *parent = h->stackPtr->parent;
+ PORT_Assert(parent);
+ PORT_Assert(parent->tag & DER_CONSTRUCTED);
+ if (parent->length != 0) {
+ PORT_SetError(SEC_ERROR_BAD_DER);
+ h->state = parseError;
+ return PR_TRUE;
+ }
+ /*
+ * NOTE: This does not check for an indefinite length
+ * composite being contained inside a definite length
+ * composite. It is not clear that is legal.
+ */
+ h->stackPtr--;
+ CreateArbNode(h);
+ } else {
+ h->stackPtr->pos = h->pos;
+
+ if (arb->tag & DER_CONSTRUCTED) {
+ SECArb *parent;
+ /*
+ * Make sure there is room on the stack before we
+ * stick anything else there.
+ */
+ PORT_Assert(h->stackPtr - h->stack < h->stackDepth);
+ if (h->stackPtr - h->stack == h->stackDepth - 1) {
+ int newDepth = h->stackDepth * 2;
+ h->stack = DS_ArenaGrow(h->mine, h->stack,
+ sizeof(ParseStackElem) *
+ h->stackDepth,
+ sizeof(ParseStackElem) *
+ newDepth);
+ h->stackPtr = h->stack + h->stackDepth + 1;
+ h->stackDepth = newDepth;
+ }
+ parent = &(h->stackPtr->arb);
+ h->stackPtr++;
+ h->stackPtr->parent = parent;
+ h->proc = ParseTag;
+ h->state = notDone;
+ h->pending = UNKNOWN;
+ } else {
+ if (arb->length < 0) {
+ PORT_SetError(SEC_ERROR_BAD_DER);
+ h->state = parseError;
+ return PR_TRUE;
+ }
+ arb->body.item.len = 0;
+ if (arb->length > 0 && h->keepLeaves) {
+ arb->body.item.data =
+ PORT_ArenaAlloc(h->his, arb->length);
+ } else {
+ arb->body.item.data = NULL;
+ }
+ h->proc = ParseLeaf;
+ h->state = notDone;
+ h->pending = arb->length;
+ }
+ }
+ } else {
+ ParseStackElem *parent;
+ PORT_Assert(h->state = leafDone);
+ PORT_Assert(h->proc == ParseLeaf);
+
+ for (;;) {
+ CreateArbNode(h);
+ if (h->stackPtr == h->stack)
+ break;
+ parent = (h->stackPtr - 1);
+ PORT_Assert(parent->arb.tag & DER_CONSTRUCTED);
+ if (parent->arb.length == 0) /* need explicit end */
+ break;
+ if (parent->pos + parent->arb.length > h->pos)
+ break;
+ if (parent->pos + parent->arb.length < h->pos) {
+ PORT_SetError(SEC_ERROR_BAD_DER);
+ h->state = parseError;
+ return PR_TRUE;
+ }
+ h->stackPtr = parent;
+ }
+ }
+ }
+ }
+ return PR_FALSE;
+}
+BERParse *
+BER_ParseInit(PLArenaPool *arena, PRBool derOnly)
+{
+ BERParse *h;
+ PLArenaPool *temp = PORT_NewArena(DER_DEFAULT_CHUNKSIZE);
+ if (temp == NULL) {
+ PORT_SetError(SEC_ERROR_NO_MEMORY);
+ return NULL;
+ }
+ h = PORT_ArenaAlloc(temp, sizeof(BERParse));
+ if (h == NULL) {
+ PORT_FreeArena(temp, PR_FALSE);
+ PORT_SetError(SEC_ERROR_NO_MEMORY);
+ return NULL;
+ }
+ h->his = arena;
+ h->mine = temp;
+ h->proc = ParseTag;
+ h->stackDepth = 20;
+ h->stack = PORT_ArenaZAlloc(h->mine,
+ sizeof(ParseStackElem) * h->stackDepth);
+ h->stackPtr = h->stack;
+ h->state = notDone;
+ h->pos = 0;
+ h->keepLeaves = PR_TRUE;
+ h->before = NULL;
+ h->after = NULL;
+ h->filter = NULL;
+ h->derOnly = derOnly;
+ return h;
+}
+
+SECArb *
+BER_ParseFini(BERParse *h)
+{
+ PLArenaPool *myArena = h->mine;
+ SECArb *arb;
+
+ if (h->state != parseComplete) {
+ arb = NULL;
+ } else {
+ arb = PORT_ArenaAlloc(h->his, sizeof(SECArb));
+ *arb = h->stackPtr->arb;
+ }
+
+ PORT_FreeArena(myArena, PR_FALSE);
+
+ return arb;
+}
+
+void
+BER_SetFilter(BERParse *h, BERFilterProc proc, void *instance)
+{
+ h->filter = proc;
+ h->filterArg = instance;
+}
+
+void
+BER_SetLeafStorage(BERParse *h, PRBool keep)
+{
+ h->keepLeaves = keep;
+}
+
+void
+BER_SetNotifyProc(BERParse *h, BERNotifyProc proc, void *instance,
+ PRBool beforeData)
+{
+ if (beforeData) {
+ h->before = proc;
+ h->beforeArg = instance;
+ } else {
+ h->after = proc;
+ h->afterArg = instance;
+ }
+}
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