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-rw-r--r--security/nss/lib/util/dersubr.c249
1 files changed, 249 insertions, 0 deletions
diff --git a/security/nss/lib/util/dersubr.c b/security/nss/lib/util/dersubr.c
new file mode 100644
index 0000000000..03d070ab2f
--- /dev/null
+++ b/security/nss/lib/util/dersubr.c
@@ -0,0 +1,249 @@
+/* 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 "secder.h"
+#include <limits.h>
+#include "secerr.h"
+
+int
+DER_LengthLength(PRUint32 len)
+{
+ if (len > 127) {
+ if (len > 255) {
+ if (len > 65535L) {
+ if (len > 16777215L) {
+ return 5;
+ } else {
+ return 4;
+ }
+ } else {
+ return 3;
+ }
+ } else {
+ return 2;
+ }
+ } else {
+ return 1;
+ }
+}
+
+unsigned char *
+DER_StoreHeader(unsigned char *buf, unsigned int code, PRUint32 len)
+{
+ unsigned char b[4];
+
+ b[0] = (unsigned char)(len >> 24);
+ b[1] = (unsigned char)(len >> 16);
+ b[2] = (unsigned char)(len >> 8);
+ b[3] = (unsigned char)len;
+ if ((code & DER_TAGNUM_MASK) == DER_SET || (code & DER_TAGNUM_MASK) == DER_SEQUENCE)
+ code |= DER_CONSTRUCTED;
+ *buf++ = code;
+ if (len > 127) {
+ if (len > 255) {
+ if (len > 65535) {
+ if (len > 16777215) {
+ *buf++ = 0x84;
+ *buf++ = b[0];
+ *buf++ = b[1];
+ *buf++ = b[2];
+ *buf++ = b[3];
+ } else {
+ *buf++ = 0x83;
+ *buf++ = b[1];
+ *buf++ = b[2];
+ *buf++ = b[3];
+ }
+ } else {
+ *buf++ = 0x82;
+ *buf++ = b[2];
+ *buf++ = b[3];
+ }
+ } else {
+ *buf++ = 0x81;
+ *buf++ = b[3];
+ }
+ } else {
+ *buf++ = b[3];
+ }
+ return buf;
+}
+
+/*
+ * XXX This should be rewritten, generalized, to take a long instead
+ * of a PRInt32.
+ */
+SECStatus
+DER_SetInteger(PLArenaPool *arena, SECItem *it, PRInt32 i)
+{
+ unsigned char bb[4];
+ unsigned len;
+
+ bb[0] = (unsigned char)(i >> 24);
+ bb[1] = (unsigned char)(i >> 16);
+ bb[2] = (unsigned char)(i >> 8);
+ bb[3] = (unsigned char)(i);
+
+ /*
+ ** Small integers are encoded in a single byte. Larger integers
+ ** require progressively more space.
+ */
+ if (i < -128) {
+ if (i < -32768L) {
+ if (i < -8388608L) {
+ len = 4;
+ } else {
+ len = 3;
+ }
+ } else {
+ len = 2;
+ }
+ } else if (i > 127) {
+ if (i > 32767L) {
+ if (i > 8388607L) {
+ len = 4;
+ } else {
+ len = 3;
+ }
+ } else {
+ len = 2;
+ }
+ } else {
+ len = 1;
+ }
+ it->data = (unsigned char *)PORT_ArenaAlloc(arena, len);
+ if (!it->data) {
+ return SECFailure;
+ }
+ it->len = len;
+ PORT_Memcpy(it->data, bb + (4 - len), len);
+ return SECSuccess;
+}
+
+/*
+ * XXX This should be rewritten, generalized, to take an unsigned long instead
+ * of a PRUint32.
+ */
+SECStatus
+DER_SetUInteger(PLArenaPool *arena, SECItem *it, PRUint32 ui)
+{
+ unsigned char bb[5];
+ int len;
+
+ bb[0] = 0;
+ bb[1] = (unsigned char)(ui >> 24);
+ bb[2] = (unsigned char)(ui >> 16);
+ bb[3] = (unsigned char)(ui >> 8);
+ bb[4] = (unsigned char)(ui);
+
+ /*
+ ** Small integers are encoded in a single byte. Larger integers
+ ** require progressively more space.
+ */
+ if (ui > 0x7f) {
+ if (ui > 0x7fff) {
+ if (ui > 0x7fffffL) {
+ if (ui >= 0x80000000L) {
+ len = 5;
+ } else {
+ len = 4;
+ }
+ } else {
+ len = 3;
+ }
+ } else {
+ len = 2;
+ }
+ } else {
+ len = 1;
+ }
+
+ it->data = (unsigned char *)PORT_ArenaAlloc(arena, len);
+ if (it->data == NULL) {
+ return SECFailure;
+ }
+
+ it->len = len;
+ PORT_Memcpy(it->data, bb + (sizeof(bb) - len), len);
+
+ return SECSuccess;
+}
+
+/*
+** Convert a der encoded *signed* integer into a machine integral value.
+** If an underflow/overflow occurs, sets error code and returns min/max.
+*/
+long
+DER_GetInteger(const SECItem *it)
+{
+ unsigned long ival;
+ PRBool negative;
+ unsigned int len = it->len;
+ unsigned char *cp = it->data;
+ size_t lsize = sizeof(ival);
+
+ PORT_Assert(len);
+ if (!len) {
+ PORT_SetError(SEC_ERROR_INPUT_LEN);
+ return 0;
+ }
+
+ negative = (PRBool)(*cp & 0x80);
+ ival = negative ? ~0 : 0;
+
+ /* Ignore leading zeros/ones. */
+ while (len && *cp == (unsigned char)ival) {
+ len--;
+ cp++;
+ }
+
+ /* Check for overflow/underflow. */
+ if (len > lsize || (len == lsize && (*cp & 0x80) != negative)) {
+ PORT_SetError(SEC_ERROR_BAD_DER);
+ return negative ? LONG_MIN : LONG_MAX;
+ }
+
+ while (len--) {
+ ival <<= 8;
+ ival |= *cp++;
+ }
+
+ return ival;
+}
+
+/*
+** Convert a der encoded *unsigned* integer into a machine integral value.
+** If an overflow occurs, sets error code and returns max.
+*/
+unsigned long
+DER_GetUInteger(SECItem *it)
+{
+ unsigned long ival = 0;
+ unsigned len = it->len;
+ unsigned char *cp = it->data;
+ unsigned long overflow = 0xffUL << ((sizeof(ival) - 1) * 8);
+
+ PORT_Assert(len);
+ if (!len) {
+ PORT_SetError(SEC_ERROR_INPUT_LEN);
+ return 0;
+ }
+
+ /* Cannot put a negative value into an unsigned container. */
+ if (*cp & 0x80) {
+ PORT_SetError(SEC_ERROR_BAD_DER);
+ return 0;
+ }
+
+ while (len) {
+ if (ival & overflow) {
+ PORT_SetError(SEC_ERROR_BAD_DER);
+ return ULONG_MAX;
+ }
+ ival = ival << 8;
+ ival |= *cp++;
+ --len;
+ }
+ return ival;
+}