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-rw-r--r--third_party/heimdal/lib/krb5/n-fold.c150
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diff --git a/third_party/heimdal/lib/krb5/n-fold.c b/third_party/heimdal/lib/krb5/n-fold.c
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+/*
+ * Copyright (c) 1999 Kungliga Tekniska Högskolan
+ * (Royal Institute of Technology, Stockholm, Sweden).
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of KTH nor the names of its contributors may be
+ * used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY KTH AND ITS CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL KTH OR ITS CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
+
+#include "krb5_locl.h"
+
+static void
+rr13(uint8_t *dst1, uint8_t *dst2, uint8_t *src, size_t len)
+{
+ int bytes = (len + 7) / 8;
+ int i;
+ const int bits = 13 % len;
+
+ for (i = 0; i < bytes; i++) {
+ int bb;
+ int b1, s1, b2, s2;
+ /* calculate first bit position of this byte */
+ bb = 8 * i - bits;
+ while(bb < 0)
+ bb += len;
+ /* byte offset and shift count */
+ b1 = bb / 8;
+ s1 = bb % 8;
+
+ if (bb + 8 > bytes * 8)
+ /* watch for wraparound */
+ s2 = (len + 8 - s1) % 8;
+ else
+ s2 = 8 - s1;
+ b2 = (b1 + 1) % bytes;
+ dst1[i] = (src[b1] << s1) | (src[b2] >> s2);
+ dst2[i] = dst1[i];
+ }
+
+ return;
+}
+
+/*
+ * Add `b' to `a', both being one's complement numbers.
+ * This function assumes that inputs *a, *b are aligned
+ * to 4 bytes.
+ */
+static void
+add1(uint8_t *a, uint8_t *b, size_t len)
+{
+ int i;
+ int carry = 0;
+ uint32_t x;
+ uint32_t left, right;
+
+ for (i = len - 1; (i+1) % 4; i--) {
+ x = a[i] + b[i] + carry;
+ carry = x > 0xff;
+ a[i] = x & 0xff;
+ }
+
+ for (i = len / 4 - 1; i >= 0; i--) {
+ left = ntohl(((uint32_t *)a)[i]);
+ right = ntohl(((uint32_t *)b)[i]);
+ x = left + right + carry;
+ carry = x < left || x < right;
+ ((uint32_t *)a)[i] = x;
+ }
+
+ for (i = len - 1; (i+1) % 4; i--) {
+ x = a[i] + carry;
+ carry = x > 0xff;
+ a[i] = x & 0xff;
+ }
+
+ for (i = len / 4 - 1; carry && i >= 0; i--) {
+ left = ((uint32_t *)a)[i];
+ x = left + carry;
+ carry = x < left;
+ ((uint32_t *)a)[i] = x;
+ }
+
+ for (i = len / 4 - 1; i >=0; i--)
+ ((uint32_t *)a)[i] = htonl(((uint32_t *)a)[i]);
+}
+
+KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
+_krb5_n_fold(const void *str, size_t len, void *key, size_t size)
+{
+ /* if len < size we need at most N * len bytes, ie < 2 * size;
+ if len > size we need at most 2 * len */
+ size_t maxlen = 2 * max(size, len);
+ size_t l = 0;
+ uint8_t *tmp;
+ uint8_t *tmpbuf;
+ uint8_t *buf1;
+ uint8_t *buf2;
+
+ tmp = malloc(maxlen + 2 * len);
+ if (tmp == NULL)
+ return ENOMEM;
+
+ buf1 = tmp + maxlen;
+ buf2 = tmp + maxlen + len;
+
+ memset(key, 0, size);
+ memcpy(buf1, str, len);
+ memcpy(tmp, buf1, len);
+ do {
+ l += len;
+ while(l >= size) {
+ add1(key, tmp, size);
+ l -= size;
+ if(l == 0)
+ break;
+ memmove(tmp, tmp + size, l);
+ }
+ rr13(tmp + l, buf2, buf1, len * 8);
+ tmpbuf = buf1;
+ buf1 = buf2;
+ buf2 = tmpbuf;
+ } while(l != 0);
+
+ memset(tmp, 0, maxlen + 2 * len);
+ free(tmp);
+ return 0;
+}