X-Git-Url: https://git.stg.codes/stg.git/blobdiff_plain/20d4dd0571e75d254444acf755a01b48a691c7c2..4271ab433cd55bbd2612292bcf39e4dc3d7274f1:/libs/smux/per_decoder.c

diff --git a/libs/smux/per_decoder.c b/libs/smux/per_decoder.c
index 16dee369..461b7262 100644
--- a/libs/smux/per_decoder.c
+++ b/libs/smux/per_decoder.c
@@ -2,6 +2,40 @@
 #include <asn_internal.h>
 #include <per_decoder.h>
 
+/*
+ * Decode a "Production of a complete encoding", X.691#10.1.
+ * The complete encoding contains at least one byte, and is an integral
+ * multiple of 8 bytes.
+ */
+asn_dec_rval_t
+uper_decode_complete(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td, void **sptr, const void *buffer, size_t size) {
+	asn_dec_rval_t rval;
+
+	rval = uper_decode(opt_codec_ctx, td, sptr, buffer, size, 0, 0);
+	if(rval.consumed) {
+		/*
+		 * We've always given 8-aligned data,
+		 * so convert bits to integral bytes.
+		 */
+		rval.consumed += 7;
+		rval.consumed >>= 3;
+	} else if(rval.code == RC_OK) {
+		if(size) {
+			if(((const uint8_t *)buffer)[0] == 0) {
+				rval.consumed = 1;	/* 1 byte */
+			} else {
+				ASN_DEBUG("Expecting single zeroed byte");
+				rval.code = RC_FAIL;
+			}
+		} else {
+			/* Must contain at least 8 bits. */
+			rval.code = RC_WMORE;
+		}
+	}
+
+	return rval;
+}
+
 asn_dec_rval_t
 uper_decode(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td, void **sptr, const void *buffer, size_t size, int skip_bits, int unused_bits) {
 	asn_codec_ctx_t s_codec_ctx;
@@ -11,7 +45,7 @@ uper_decode(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td, void **sp
 	if(skip_bits < 0 || skip_bits > 7
 	|| unused_bits < 0 || unused_bits > 7
 	|| (unused_bits > 0 && !size))
-		_ASN_DECODE_FAILED;
+		ASN__DECODE_FAILED;
 
 	/*
 	 * Stack checker requires that the codec context
@@ -25,27 +59,31 @@ uper_decode(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td, void **sp
 	} else {
 		/* If context is not given, be security-conscious anyway */
 		memset(&s_codec_ctx, 0, sizeof(s_codec_ctx));
-		s_codec_ctx.max_stack_size = _ASN_DEFAULT_STACK_MAX;
+		s_codec_ctx.max_stack_size = ASN__DEFAULT_STACK_MAX;
 		opt_codec_ctx = &s_codec_ctx;
 	}
 
 	/* Fill in the position indicator */
+	memset(&pd, 0, sizeof(pd));
 	pd.buffer = (const uint8_t *)buffer;
 	pd.nboff = skip_bits;
 	pd.nbits = 8 * size - unused_bits; /* 8 is CHAR_BIT from <limits.h> */
 	if(pd.nboff > pd.nbits)
-		_ASN_DECODE_FAILED;
+		ASN__DECODE_FAILED;
 
 	/*
 	 * Invoke type-specific decoder.
 	 */
 	if(!td->uper_decoder)
-		_ASN_DECODE_FAILED;	/* PER is not compiled in */
+		ASN__DECODE_FAILED;	/* PER is not compiled in */
 	rval = td->uper_decoder(opt_codec_ctx, td, 0, sptr, &pd);
 	if(rval.code == RC_OK) {
 		/* Return the number of consumed bits */
 		rval.consumed = ((pd.buffer - (const uint8_t *)buffer) << 3)
 					+ pd.nboff - skip_bits;
+		ASN_DEBUG("PER decoding consumed %ld, counted %ld",
+			(long)rval.consumed, (long)pd.moved);
+		assert(rval.consumed == pd.moved);
 	} else {
 		/* PER codec is not a restartable */
 		rval.consumed = 0;