remove libasn1c dependency and use asn1c without libasn1c
TODO: re-introduce talloc integration for asn1 runtime
Change-Id: I2140509c5359727f304470249be2a726b9a8deb1
diff --git a/src/rspro/ber_tlv_length.c b/src/rspro/ber_tlv_length.c
new file mode 100644
index 0000000..b87e75e
--- /dev/null
+++ b/src/rspro/ber_tlv_length.c
@@ -0,0 +1,178 @@
+/*-
+ * Copyright (c) 2003, 2004 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#include <asn_internal.h>
+#include <ber_tlv_length.h>
+#include <ber_tlv_tag.h>
+
+ssize_t
+ber_fetch_length(int _is_constructed, const void *bufptr, size_t size,
+ ber_tlv_len_t *len_r) {
+ const uint8_t *buf = (const uint8_t *)bufptr;
+ unsigned oct;
+
+ if(size == 0)
+ return 0; /* Want more */
+
+ oct = *(const uint8_t *)buf;
+ if((oct & 0x80) == 0) {
+ /*
+ * Short definite length.
+ */
+ *len_r = oct; /* & 0x7F */
+ return 1;
+ } else {
+ ber_tlv_len_t len;
+ size_t skipped;
+
+ if(_is_constructed && oct == 0x80) {
+ *len_r = -1; /* Indefinite length */
+ return 1;
+ }
+
+ if(oct == 0xff) {
+ /* Reserved in standard for future use. */
+ return -1;
+ }
+
+ oct &= 0x7F; /* Leave only the 7 LS bits */
+ for(len = 0, buf++, skipped = 1;
+ oct && (++skipped <= size); buf++, oct--) {
+
+ len = (len << 8) | *buf;
+ if(len < 0
+ || (len >> ((8 * sizeof(len)) - 8) && oct > 1)) {
+ /*
+ * Too large length value.
+ */
+ return -1;
+ }
+ }
+
+ if(oct == 0) {
+ ber_tlv_len_t lenplusepsilon = (size_t)len + 1024;
+ /*
+ * Here length may be very close or equal to 2G.
+ * However, the arithmetics used in some decoders
+ * may add some (small) quantities to the length,
+ * to check the resulting value against some limits.
+ * This may result in integer wrap-around, which
+ * we try to avoid by checking it earlier here.
+ */
+ if(lenplusepsilon < 0) {
+ /* Too large length value */
+ return -1;
+ }
+
+ *len_r = len;
+ return skipped;
+ }
+
+ return 0; /* Want more */
+ }
+
+}
+
+ssize_t
+ber_skip_length(asn_codec_ctx_t *opt_codec_ctx,
+ int _is_constructed, const void *ptr, size_t size) {
+ ber_tlv_len_t vlen; /* Length of V in TLV */
+ ssize_t tl; /* Length of L in TLV */
+ ssize_t ll; /* Length of L in TLV */
+ size_t skip;
+
+ /*
+ * Make sure we didn't exceed the maximum stack size.
+ */
+ if(_ASN_STACK_OVERFLOW_CHECK(opt_codec_ctx))
+ return -1;
+
+ /*
+ * Determine the size of L in TLV.
+ */
+ ll = ber_fetch_length(_is_constructed, ptr, size, &vlen);
+ if(ll <= 0) return ll;
+
+ /*
+ * Definite length.
+ */
+ if(vlen >= 0) {
+ skip = ll + vlen;
+ if(skip > size)
+ return 0; /* Want more */
+ return skip;
+ }
+
+ /*
+ * Indefinite length!
+ */
+ ASN_DEBUG("Skipping indefinite length");
+ for(skip = ll, ptr = ((const char *)ptr) + ll, size -= ll;;) {
+ ber_tlv_tag_t tag;
+
+ /* Fetch the tag */
+ tl = ber_fetch_tag(ptr, size, &tag);
+ if(tl <= 0) return tl;
+
+ ll = ber_skip_length(opt_codec_ctx,
+ BER_TLV_CONSTRUCTED(ptr),
+ ((const char *)ptr) + tl, size - tl);
+ if(ll <= 0) return ll;
+
+ skip += tl + ll;
+
+ /*
+ * This may be the end of the indefinite length structure,
+ * two consecutive 0 octets.
+ * Check if it is true.
+ */
+ if(((const uint8_t *)ptr)[0] == 0
+ && ((const uint8_t *)ptr)[1] == 0)
+ return skip;
+
+ ptr = ((const char *)ptr) + tl + ll;
+ size -= tl + ll;
+ }
+
+ /* UNREACHABLE */
+}
+
+size_t
+der_tlv_length_serialize(ber_tlv_len_t len, void *bufp, size_t size) {
+ size_t required_size; /* Size of len encoding */
+ uint8_t *buf = (uint8_t *)bufp;
+ uint8_t *end;
+ size_t i;
+
+ if(len <= 127) {
+ /* Encoded in 1 octet */
+ if(size) *buf = (uint8_t)len;
+ return 1;
+ }
+
+ /*
+ * Compute the size of the subsequent bytes.
+ */
+ for(required_size = 1, i = 8; i < 8 * sizeof(len); i += 8) {
+ if(len >> i)
+ required_size++;
+ else
+ break;
+ }
+
+ if(size <= required_size)
+ return required_size + 1;
+
+ *buf++ = (uint8_t)(0x80 | required_size); /* Length of the encoding */
+
+ /*
+ * Produce the len encoding, space permitting.
+ */
+ end = buf + required_size;
+ for(i -= 8; buf < end; i -= 8, buf++)
+ *buf = (uint8_t)(len >> i);
+
+ return required_size + 1;
+}
+