+#include "internal/cryptlib.h"
+#include "internal/numbers.h"
+#include <limits.h>
+#include <openssl/asn1.h>
+#include <openssl/bn.h>
+#include "asn1_locl.h"
+
+ASN1_INTEGER *ASN1_INTEGER_dup(const ASN1_INTEGER *x)
+{
+ return ASN1_STRING_dup(x);
+}
+
+int ASN1_INTEGER_cmp(const ASN1_INTEGER *x, const ASN1_INTEGER *y)
+{
+ int neg, ret;
+ /* Compare signs */
+ neg = x->type & V_ASN1_NEG;
+ if (neg != (y->type & V_ASN1_NEG)) {
+ if (neg)
+ return -1;
+ else
+ return 1;
+ }
+
+ ret = ASN1_STRING_cmp(x, y);
+
+ if (neg)
+ return -ret;
+ else
+ return ret;
+}
+
+/*-
+ * This converts a big endian buffer and sign into its content encoding.
+ * This is used for INTEGER and ENUMERATED types.
+ * The internal representation is an ASN1_STRING whose data is a big endian
+ * representation of the value, ignoring the sign. The sign is determined by
+ * the type: if type & V_ASN1_NEG is true it is negative, otherwise positive.
+ *
+ * Positive integers are no problem: they are almost the same as the DER
+ * encoding, except if the first byte is >= 0x80 we need to add a zero pad.
+ *
+ * Negative integers are a bit trickier...
+ * The DER representation of negative integers is in 2s complement form.
+ * The internal form is converted by complementing each octet and finally
+ * adding one to the result. This can be done less messily with a little trick.
+ * If the internal form has trailing zeroes then they will become FF by the
+ * complement and 0 by the add one (due to carry) so just copy as many trailing
+ * zeros to the destination as there are in the source. The carry will add one
+ * to the last none zero octet: so complement this octet and add one and finally
+ * complement any left over until you get to the start of the string.
+ *
+ * Padding is a little trickier too. If the first bytes is > 0x80 then we pad
+ * with 0xff. However if the first byte is 0x80 and one of the following bytes
+ * is non-zero we pad with 0xff. The reason for this distinction is that 0x80
+ * followed by optional zeros isn't padded.
+ */
+
+static size_t i2c_ibuf(const unsigned char *b, size_t blen, int neg,
+ unsigned char **pp)
+{
+ int pad = 0;
+ size_t ret, i;
+ unsigned char *p, pb = 0;
+ const unsigned char *n;
+
+ if (b == NULL || blen == 0)
+ ret = 1;
+ else {
+ ret = blen;
+ i = b[0];
+ if (ret == 1 && i == 0)
+ neg = 0;
+ if (!neg && (i > 127)) {
+ pad = 1;
+ pb = 0;
+ } else if (neg) {
+ if (i > 128) {
+ pad = 1;
+ pb = 0xFF;
+ } else if (i == 128) {
+ /*
+ * Special case: if any other bytes non zero we pad:
+ * otherwise we don't.
+ */
+ for (i = 1; i < blen; i++)
+ if (b[i]) {
+ pad = 1;
+ pb = 0xFF;
+ break;
+ }
+ }
+ }
+ ret += pad;
+ }
+ if (pp == NULL)
+ return ret;
+ p = *pp;
+
+ if (pad)
+ *(p++) = pb;
+ if (b == NULL || blen == 0)
+ *p = 0;
+ else if (!neg)
+ memcpy(p, b, blen);
+ else {
+ /* Begin at the end of the encoding */
+ n = b + blen - 1;
+ p += blen - 1;
+ i = blen;
+ /* Copy zeros to destination as long as source is zero */
+ while (!*n && i > 1) {
+ *(p--) = 0;
+ n--;
+ i--;
+ }
+ /* Complement and increment next octet */
+ *(p--) = ((*(n--)) ^ 0xff) + 1;
+ i--;
+ /* Complement any octets left */
+ for (; i > 0; i--)
+ *(p--) = *(n--) ^ 0xff;
+ }
+
+ *pp += ret;
+ return ret;
+}
+
+/*
+ * convert content octets into a big endian buffer. Returns the length
+ * of buffer or 0 on error: for malformed INTEGER. If output buffer is
+ * NULL just return length.
+ */
+
+static size_t c2i_ibuf(unsigned char *b, int *pneg,
+ const unsigned char *p, size_t plen)
+{
+ size_t i;
+ int neg, pad;
+ /* Zero content length is illegal */
+ if (plen == 0) {
+ ASN1err(ASN1_F_C2I_IBUF, ASN1_R_ILLEGAL_ZERO_CONTENT);
+ return 0;
+ }
+ neg = p[0] & 0x80;
+ if (pneg)
+ *pneg = neg;
+ /* Handle common case where length is 1 octet separately */
+ if (plen == 1) {
+ if (b) {
+ if (neg)
+ b[0] = (p[0] ^ 0xFF) + 1;
+ else
+ b[0] = p[0];
+ }
+ return 1;
+ }
+ if (p[0] == 0 || p[0] == 0xFF)
+ pad = 1;
+ else
+ pad = 0;
+ /* reject illegal padding: first two octets MSB can't match */
+ if (pad && (neg == (p[1] & 0x80))) {
+ ASN1err(ASN1_F_C2I_IBUF, ASN1_R_ILLEGAL_PADDING);
+ return 0;
+ }
+ /* If positive just copy across */
+ if (neg == 0) {
+ if (b)
+ memcpy(b, p + pad, plen - pad);
+ return plen - pad;
+ }
+
+ if (neg && pad) {
+ /* check is any following octets are non zero */
+ for (i = 1; i < plen; i++) {
+ if (p[i] != 0)
+ break;
+ }
+ /* if all bytes are zero handle as special case */
+ if (i == plen) {
+ if (b) {
+ b[0] = 1;
+ memset(b + 1, 0, plen - 1);
+ }
+ return plen;
+ }
+ }
+
+ plen -= pad;
+ /* Must be negative: calculate twos complement */
+ if (b) {
+ const unsigned char *from = p + plen - 1 + pad;
+ unsigned char *to = b + plen - 1;
+ i = plen;
+ while (*from == 0 && i) {
+ *to-- = 0;
+ i--;
+ from--;
+ }
+ *to-- = (*from-- ^ 0xff) + 1;
+ OPENSSL_assert(i != 0);
+ i--;
+ for (; i > 0; i--)
+ *to-- = *from-- ^ 0xff;
+ }
+ return plen;
+}
+
+int i2c_ASN1_INTEGER(ASN1_INTEGER *a, unsigned char **pp)
+{
+ return i2c_ibuf(a->data, a->length, a->type & V_ASN1_NEG, pp);
+}
+
+/* Convert big endian buffer into uint64_t, return 0 on error */
+static int asn1_get_uint64(uint64_t *pr, const unsigned char *b, size_t blen)
+{
+ size_t i;
+ if (blen > sizeof(*pr)) {
+ ASN1err(ASN1_F_ASN1_GET_UINT64, ASN1_R_TOO_LARGE);
+ return 0;
+ }
+ *pr = 0;
+ if (b == NULL)
+ return 0;
+ for (i = 0; i < blen; i++) {
+ *pr <<= 8;
+ *pr |= b[i];
+ }
+ return 1;
+}
+
+static size_t asn1_put_uint64(unsigned char *b, uint64_t r)
+{
+ if (r >= 0x100) {
+ unsigned char *p;
+ uint64_t rtmp = r;
+ size_t i = 0;
+
+ /* Work out how many bytes we need */
+ while (rtmp) {
+ rtmp >>= 8;
+ i++;
+ }
+
+ /* Copy from end to beginning */
+ p = b + i - 1;
+
+ do {
+ *p-- = r & 0xFF;
+ r >>= 8;
+ } while (p >= b);
+
+ return i;
+ }
+
+ b[0] = (unsigned char)r;
+ return 1;
+
+}
+
+/*
+ * Absolute value of INT64_MIN: we can't just use -INT64_MIN as it produces
+ * overflow warnings.
+ */
+
+#define ABS_INT64_MIN \
+ ((uint64_t)INT64_MAX + (uint64_t)(-(INT64_MIN + INT64_MAX)))
+
+/* signed version of asn1_get_uint64 */
+static int asn1_get_int64(int64_t *pr, const unsigned char *b, size_t blen,
+ int neg)
+{
+ uint64_t r;
+ if (asn1_get_uint64(&r, b, blen) == 0)
+ return 0;
+ if (neg) {
+ if (r > ABS_INT64_MIN) {
+ ASN1err(ASN1_F_ASN1_GET_INT64, ASN1_R_TOO_SMALL);
+ return 0;
+ }
+ *pr = -(int64_t)r;
+ } else {
+ if (r > INT64_MAX) {
+ ASN1err(ASN1_F_ASN1_GET_INT64, ASN1_R_TOO_LARGE);
+ return 0;
+ }
+ *pr = (int64_t)r;
+ }
+ return 1;
+}
+
+/* Convert ASN1 INTEGER content octets to ASN1_INTEGER structure */
+ASN1_INTEGER *c2i_ASN1_INTEGER(ASN1_INTEGER **a, const unsigned char **pp,
+ long len)
+{
+ ASN1_INTEGER *ret = NULL;
+ size_t r;
+ int neg;
+
+ r = c2i_ibuf(NULL, NULL, *pp, len);
+
+ if (r == 0)
+ return NULL;