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-rw-r--r--src/pk/asn1/der/set/der_encode_setof.c162
1 files changed, 162 insertions, 0 deletions
diff --git a/src/pk/asn1/der/set/der_encode_setof.c b/src/pk/asn1/der/set/der_encode_setof.c
new file mode 100644
index 0000000..6c12eb4
--- /dev/null
+++ b/src/pk/asn1/der/set/der_encode_setof.c
@@ -0,0 +1,162 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
+ */
+#include "tomcrypt.h"
+
+/**
+ @file der_encode_setof.c
+ ASN.1 DER, Encode SET OF, Tom St Denis
+*/
+
+#ifdef LTC_DER
+
+struct edge {
+ unsigned char *start;
+ unsigned long size;
+};
+
+static int qsort_helper(const void *a, const void *b)
+{
+ struct edge *A = (struct edge *)a, *B = (struct edge *)b;
+ int r;
+ unsigned long x;
+
+ /* compare min length */
+ r = XMEMCMP(A->start, B->start, MIN(A->size, B->size));
+
+ if (r == 0 && A->size != B->size) {
+ if (A->size > B->size) {
+ for (x = B->size; x < A->size; x++) {
+ if (A->start[x]) {
+ return 1;
+ }
+ }
+ } else {
+ for (x = A->size; x < B->size; x++) {
+ if (B->start[x]) {
+ return -1;
+ }
+ }
+ }
+ }
+
+ return r;
+}
+
+/**
+ Encode a SETOF stucture
+ @param list The list of items to encode
+ @param inlen The number of items in the list
+ @param out [out] The destination
+ @param outlen [in/out] The size of the output
+ @return CRYPT_OK on success
+*/
+int der_encode_setof(ltc_asn1_list *list, unsigned long inlen,
+ unsigned char *out, unsigned long *outlen)
+{
+ unsigned long x, y, z, hdrlen;
+ int err;
+ struct edge *edges;
+ unsigned char *ptr, *buf;
+
+ /* check that they're all the same type */
+ for (x = 1; x < inlen; x++) {
+ if (list[x].type != list[x-1].type) {
+ return CRYPT_INVALID_ARG;
+ }
+ }
+
+ /* alloc buffer to store copy of output */
+ buf = XCALLOC(1, *outlen);
+ if (buf == NULL) {
+ return CRYPT_MEM;
+ }
+
+ /* encode list */
+ if ((err = der_encode_sequence_ex(list, inlen, buf, outlen, LTC_ASN1_SETOF)) != CRYPT_OK) {
+ XFREE(buf);
+ return err;
+ }
+
+ /* allocate edges */
+ edges = XCALLOC(inlen, sizeof(*edges));
+ if (edges == NULL) {
+ XFREE(buf);
+ return CRYPT_MEM;
+ }
+
+ /* skip header */
+ ptr = buf + 1;
+
+ /* now skip length data */
+ x = *ptr++;
+ if (x >= 0x80) {
+ ptr += (x & 0x7F);
+ }
+
+ /* get the size of the static header */
+ hdrlen = ((unsigned long)ptr) - ((unsigned long)buf);
+
+
+ /* scan for edges */
+ x = 0;
+ while (ptr < (buf + *outlen)) {
+ /* store start */
+ edges[x].start = ptr;
+
+ /* skip type */
+ z = 1;
+
+ /* parse length */
+ y = ptr[z++];
+ if (y < 128) {
+ edges[x].size = y;
+ } else {
+ y &= 0x7F;
+ edges[x].size = 0;
+ while (y--) {
+ edges[x].size = (edges[x].size << 8) | ((unsigned long)ptr[z++]);
+ }
+ }
+
+ /* skip content */
+ edges[x].size += z;
+ ptr += edges[x].size;
+ ++x;
+ }
+
+ /* sort based on contents (using edges) */
+ XQSORT(edges, inlen, sizeof(*edges), &qsort_helper);
+
+ /* copy static header */
+ XMEMCPY(out, buf, hdrlen);
+
+ /* copy+sort using edges+indecies to output from buffer */
+ for (y = hdrlen, x = 0; x < inlen; x++) {
+ XMEMCPY(out+y, edges[x].start, edges[x].size);
+ y += edges[x].size;
+ }
+
+#ifdef LTC_CLEAN_STACK
+ zeromem(buf, *outlen);
+#endif
+
+ /* free buffers */
+ XFREE(edges);
+ XFREE(buf);
+
+ return CRYPT_OK;
+}
+
+#endif
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/set/der_encode_setof.c,v $ */
+/* $Revision: 1.11 $ */
+/* $Date: 2006/03/31 14:15:35 $ */