1 files changed, 305 insertions, 0 deletions
diff --git a/skeletons/INTEGER.c b/skeletons/INTEGER.c
new file mode 100644
index 00000000..b1a8c29b
--- /dev/null
+++ b/skeletons/INTEGER.c
@@ -0,0 +1,305 @@
+/*-
+ * Copyright (c) 2003 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#include <INTEGER.h>
+#include <assert.h>
+#include <errno.h>
+
+/*
+ * INTEGER basic type description.
+ */
+static ber_tlv_tag_t asn1_DEF_INTEGER_tags[] = {
+	(ASN_TAG_CLASS_UNIVERSAL | (2 << 2))
+};
+asn1_TYPE_descriptor_t asn1_DEF_INTEGER = {
+	"INTEGER",
+	asn_generic_no_constraint,
+	INTEGER_decode_ber,
+	INTEGER_encode_der,
+	INTEGER_print,
+	INTEGER_free,
+	0, /* Use generic outmost tag fetcher */
+	asn1_DEF_INTEGER_tags,
+	sizeof(asn1_DEF_INTEGER_tags)/sizeof(asn1_DEF_INTEGER_tags[0]),
+	1,	/* Single UNIVERSAL tag may be implicitly overriden */
+	0	/* Always in primitive form */
+};
+
+/*
+ * Decode INTEGER type.
+ */
+ber_dec_rval_t
+INTEGER_decode_ber(asn1_TYPE_descriptor_t *td,
+	void **int_structure, void *buf_ptr, size_t size, int tag_mode) {
+	INTEGER_t *st = *int_structure;
+	ber_dec_rval_t rval;
+	ber_dec_ctx_t ctx = { 0 };
+	ber_tlv_len_t length;
+
+	/*
+	 * If the structure is not there, allocate it.
+	 */
+	if(st == NULL) {
+		st = *int_structure = CALLOC(1, sizeof(*st));
+		if(st == NULL) {
+			rval.code = RC_FAIL;
+			rval.consumed = 0;
+			return rval;
+		}
+	}
+
+	ASN_DEBUG("Decoding %s as INTEGER (tm=%d)",
+		td->name, tag_mode);
+
+	/*
+	 * Check tags.
+	 */
+	rval = ber_check_tags(td, &ctx,
+		buf_ptr, size, tag_mode, &length, 0);
+	if(rval.code != RC_OK)
+		return rval;
+
+	ASN_DEBUG("%s length is %d bytes", td->name, (int)length);
+
+	/*
+	 * Make sure we have this length.
+	 */
+	buf_ptr += rval.consumed;
+	size -= rval.consumed;
+	if(length > size) {
+		rval.code = RC_WMORE;
+		rval.consumed = 0;
+		return rval;
+	}
+
+	st->buf = MALLOC(length);
+	if(st->buf) {
+		st->size = length;
+	} else {
+		rval.code = RC_FAIL;
+		rval.consumed = 0;
+		return rval;
+	}
+
+	memcpy(st->buf, buf_ptr, st->size);
+
+	rval.code = RC_OK;
+	rval.consumed += length;
+
+	ASN_DEBUG("Took %ld/%ld bytes to encode %s",
+		(long)rval.consumed,
+		(long)length, td->name);
+
+	return rval;
+}
+
+/*
+ * Encode INTEGER type using DER.
+ */
+der_enc_rval_t
+INTEGER_encode_der(asn1_TYPE_descriptor_t *sd, void *ptr,
+	int tag_mode, ber_tlv_tag_t tag,
+	asn_app_consume_bytes_f *cb, void *app_key) {
+	der_enc_rval_t erval;
+	INTEGER_t *st = ptr;
+
+	ASN_DEBUG("%s %s as INTEGER (tm=%d)",
+		cb?"Encoding":"Estimating", sd->name, tag_mode);
+
+	/*
+	 * Canonicalize integer in the buffer.
+	 * (Remove too long sign extension, remove some first 0x00 bytes)
+	 */
+	if(st->buf) {
+		uint8_t *buf = st->buf;
+		uint8_t *end1 = buf + st->size - 1;
+		int shift;
+
+		/* Compute the number of superfluous leading bytes */
+		for(; buf < end1; buf++) {
+			/*
+			 * If the contents octets of an integer value encoding
+			 * consist of more than one octet, then the bits of the
+			 * first octet and bit 8 of the second octet:
+			 * a) shall not all be ones; and
+			 * b) shall not all be zero.
+			 */
+			switch(*buf) {
+			case 0x00: if((buf[1] & 0x80) == 0)
+					continue;
+				break;
+			case 0xff: if((buf[1] & 0x80))
+					continue;
+				break;
+			}
+			break;
+		}
+
+		/* Remove leading superfluous bytes from the integer */
+		shift = buf - st->buf;
+		if(shift) {
+			uint8_t *nb = st->buf;
+			uint8_t *end;
+
+			st->size -= shift;	/* New size, minus bad bytes */
+			end = nb + st->size;
+
+			for(; nb < end; nb++, buf++)
+				*nb = *buf;
+		}
+
+	} /* if(1) */
+
+	erval.encoded = der_write_tags(sd, st->size, tag_mode, tag,
+		cb, app_key);
+	ASN_DEBUG("INTEGER %s wrote tags %d", sd->name, (int)erval.encoded);
+	if(erval.encoded == -1) {
+		erval.failed_type = sd;
+		erval.structure_ptr = ptr;
+		return erval;
+	}
+
+	if(cb && st->buf) {
+		ssize_t ret;
+
+		ret = cb(st->buf, st->size, app_key);
+		if(ret == -1) {
+			erval.encoded = -1;
+			erval.failed_type = sd;
+			erval.structure_ptr = ptr;
+			return erval;
+		}
+	} else {
+		assert(st->buf || st->size == 0);
+	}
+
+	erval.encoded += st->size;
+
+	return erval;
+}
+
+/*
+ * INTEGER specific human-readable output.
+ */
+int
+INTEGER_print(asn1_TYPE_descriptor_t *td, const void *sptr, int ilevel,
+	asn_app_consume_bytes_f *cb, void *app_key) {
+	const INTEGER_t *st = sptr;
+	char scratch[32];
+	uint8_t *buf = st->buf;
+	uint8_t *buf_end = st->buf + st->size;
+	signed long accum;
+	char *p;
+	int ret;
+
+	if(!st && !st->buf) return cb("<absent>", 8, app_key);
+
+	if(st->size == 0)
+		return cb("0", 1, app_key);
+
+	/* Simple case: the integer size is small */
+	if(st->size < sizeof(accum) || (st->buf[0] & 0x80)) {
+		accum = (st->buf[0] & 0x80) ? -1 : 0;
+		for(; buf < buf_end; buf++)
+			accum = (accum << 8) | *buf;
+		ret = snprintf(scratch, sizeof(scratch), "%ld", accum);
+		assert(ret > 0 && ret < sizeof(scratch));
+		return cb(scratch, ret, app_key);
+	}
+
+	/* Output in the long xx:yy:zz... format */
+	for(p = scratch; buf < buf_end; buf++) {
+		static char h2c[16] = "0123456789ABCDEF";
+		if((p - scratch) >= (sizeof(scratch) / 2)) {
+			/* Flush buffer */
+			if(cb(scratch, p - scratch, app_key))
+				return -1;
+			p = scratch;
+		}
+		*p++ = h2c[*buf >> 4];
+		*p++ = h2c[*buf & 0x0F];
+		*p++ = ':';
+	}
+
+	return cb(scratch, p - scratch, app_key);
+}
+
+void
+INTEGER_free(asn1_TYPE_descriptor_t *td, void *ptr, int contents_only) {
+	INTEGER_t *st = ptr;
+
+	if(!td || !st)
+		return;
+
+	ASN_DEBUG("Freeing %s as INTEGER (%d, %p, %p)",
+		td->name, contents_only, st, st->buf);
+
+	if(st->buf) {
+		FREEMEM(st->buf);
+	}
+
+	if(!contents_only) {
+		FREEMEM(st);
+	}
+}
+
+int
+asn1_INTEGER2long(const INTEGER_t *iptr, long *lptr) {
+	uint8_t *b, *end;
+	size_t size;
+	long l;
+
+	/* Sanity checking */
+	if(!iptr || !iptr->buf || !lptr) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	/* Cache the begin/end of the buffer */
+	b = iptr->buf;	/* Start of the INTEGER buffer */
+	size = iptr->size;
+	end = b + size;	/* Where to stop */
+
+	if(size > sizeof(long)) {
+		uint8_t *end1 = end - 1;
+		/*
+		 * Slightly more advanced processing,
+		 * able to >sizeof(long) bytes,
+		 * when the actual value is small
+		 * (0x0000000000abcdef would yield a fine 0x00abcdef)
+		 */
+		/* Skip out the insignificant leading bytes */
+		for(; b < end1; b++) {
+			switch(*b) {
+			case 0x00: if((b[1] & 0x80) == 0) continue; break;
+			case 0xff: if((b[1] & 0x80) != 0) continue; break;
+			}
+			break;
+		}
+
+		size = end - b;
+		if(size > sizeof(long)) {
+			/* Still cannot fit the long */
+			errno = ERANGE;
+			return -1;
+		}
+	}
+
+	/* Shortcut processing of a corner case */
+	if(end == b) {
+		*lptr = 0;
+		return 0;
+	}
+
+	/* Perform the sign initialization */
+	/* Actually l = -(*b >> 7); gains nothing, yet unreadable! */
+	if((*b >> 7)) l = -1; else l = 0;
+
+	/* Conversion engine */
+	for(; b < end; b++)
+		l = (l << 8) | *b;
+
+	*lptr = l;
+	return 0;
+}