fix UPER decoding of large [bit-]strings of size a multiple of 16K

.gitignore

@@ -44,6 +44,7 @@ stamp-h*
 
 # /tests/tests-skeletons
 /tests/tests-skeletons/check-*
+!/tests/tests-skeletons/check-*.c
 
 # /doc/docsrc
 doc/docsrc/*.aux

ChangeLog

@@ -25,6 +25,8 @@
       (Severity: low; Security impact: medium)
     * Fix UPER string decoding constrained only by lower bound > 0
       (Severity: low; Security impact: none)
+    * Fix UPER decoding of large [bit-]strings of size a multiple of 16K
+      (Severity: low; Security impact: none)
     * Fix XER decoder crash on maliciously constructed ENUMERATED input.
       (Severity: medium; Security impact: medium)
 

skeletons/ANY.c

@@ -218,6 +218,7 @@ ANY_decode_uper(const asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
         /* Get the PER length */
         raw_len = uper_get_length(pd, -1, 0, &repeat);
         if(raw_len < 0) RETURN(RC_WMORE);
+        if(raw_len == 0 && st->buf) break;
 
         ASN_DEBUG("Got PER length len %zu, %s (%s)", raw_len,
                   repeat ? "repeat" : "once", td->name);
@@ -254,8 +255,9 @@ ANY_encode_uper(asn_TYPE_descriptor_t *td,
 
     buf = st->buf;
     size = st->size;
-    while(size) {
-        ssize_t may_save = uper_put_length(po, size);
+    do {
+        int need_eom = 0;
+        ssize_t may_save = uper_put_length(po, size, &need_eom);
         if(may_save < 0) ASN__ENCODE_FAILED;
 
         ret = per_put_many_bits(po, buf, may_save * 8);
@@ -264,7 +266,9 @@ ANY_encode_uper(asn_TYPE_descriptor_t *td,
         buf += may_save;
         size -= may_save;
         assert(!(may_save & 0x07) || !size);
-    }
+        if(need_eom && uper_put_length(po, 0, 0))
+            ASN__ENCODE_FAILED; /* End of Message length */
+    } while(size);
 
     ASN__ENCODED_OK(er);
 }

skeletons/BIT_STRING.c

@@ -396,6 +396,7 @@ BIT_STRING_decode_uper(const asn_codec_ctx_t *opt_codec_ctx,
 		raw_len = uper_get_length(pd, csiz->effective_bits, csiz->lower_bound,
 		                          &repeat);
 		if(raw_len < 0) RETURN(RC_WMORE);
+        if(raw_len == 0 && st->buf) break;
 
 		ASN_DEBUG("Got PER length eb %ld, len %ld, %s (%s)",
 			(long)csiz->effective_bits, (long)raw_len,
@@ -442,8 +443,6 @@ BIT_STRING_encode_uper(asn_TYPE_descriptor_t *td,
 	if(specs->subvariant == ASN_OSUBV_BIT) {
         if((st->size == 0 && st->bits_unused) || (st->bits_unused & ~7))
             ASN__ENCODE_FAILED;
-        ASN_DEBUG("BIT STRING of %zu bytes, %d bits unused", size_in_bits,
-                  st->bits_unused);
     } else {
 		ASN__ENCODE_FAILED;
     }
@@ -518,7 +517,8 @@ BIT_STRING_encode_uper(asn_TYPE_descriptor_t *td,
 
     buf = st->buf;
     do {
-        ssize_t maySave = uper_put_length(po, size_in_bits);
+        int need_eom = 0;
+        ssize_t maySave = uper_put_length(po, size_in_bits, &need_eom);
         if(maySave < 0) ASN__ENCODE_FAILED;
 
         ASN_DEBUG("Encoding %zd of %zu", maySave, size_in_bits);
@@ -529,6 +529,8 @@ BIT_STRING_encode_uper(asn_TYPE_descriptor_t *td,
         buf += maySave >> 3;
         size_in_bits -= maySave;
         assert(!(maySave & 0x07) || !size_in_bits);
+        if(need_eom && uper_put_length(po, 0, 0))
+            ASN__ENCODE_FAILED; /* End of Message length */
     } while(size_in_bits);
 
     ASN__ENCODED_OK(er);

skeletons/INTEGER.c

@@ -770,13 +770,15 @@ INTEGER_encode_uper(asn_TYPE_descriptor_t *td,
 	}
 
 	for(buf = st->buf, end = st->buf + st->size; buf < end;) {
-		ssize_t mayEncode = uper_put_length(po, end - buf);
-		if(mayEncode < 0)
+        int need_eom = 0;
+        ssize_t mayEncode = uper_put_length(po, end - buf, &need_eom);
+        if(mayEncode < 0)
 			ASN__ENCODE_FAILED;
 		if(per_put_many_bits(po, buf, 8 * mayEncode))
 			ASN__ENCODE_FAILED;
 		buf += mayEncode;
-	}
+        if(need_eom && uper_put_length(po, 0, 0)) ASN__ENCODE_FAILED;
+    }
 
 	ASN__ENCODED_OK(er);
 }

skeletons/OCTET_STRING.c

@@ -1253,8 +1253,8 @@ OCTET_STRING_per_get_characters(asn_per_data_t *po, uint8_t *buf,
 	}
 
 	for(; buf < end; buf += bpc) {
-		int code = per_get_few_bits(po, unit_bits);
-		int ch = code + lb;
+		int32_t code = per_get_few_bits(po, unit_bits);
+		int32_t ch = code + lb;
 		if(code < 0) return -1;	/* WMORE */
 		if(ch > ub) {
 			ASN_DEBUG("Code %d is out of range (%ld..%ld)",
@@ -1471,6 +1471,7 @@ OCTET_STRING_decode_uper(const asn_codec_ctx_t *opt_codec_ctx,
 		raw_len = uper_get_length(pd, csiz->effective_bits, csiz->lower_bound,
 		                          &repeat);
 		if(raw_len < 0) RETURN(RC_WMORE);
+		if(raw_len == 0 && st->buf) break;
 
 		ASN_DEBUG("Got PER length eb %ld, len %ld, %s (%s)",
 			(long)csiz->effective_bits, (long)raw_len,
@@ -1610,27 +1611,27 @@ OCTET_STRING_encode_uper(asn_TYPE_descriptor_t *td,
 
     ASN_DEBUG("Encoding %zu bytes", st->size);
 
-    if(size_in_units == 0) {
-        if(uper_put_length(po, 0)) ASN__ENCODE_FAILED;
-        ASN__ENCODED_OK(er);
-    }
-
     buf = st->buf;
-    while(size_in_units) {
-        ssize_t maySave = uper_put_length(po, size_in_units);
-        if(maySave < 0) ASN__ENCODE_FAILED;
+    ASN_DEBUG("Encoding %zu in units", size_in_units);
+    do {
+        int need_eom = 0;
+        ssize_t may_save = uper_put_length(po, size_in_units, &need_eom);
+        if(may_save < 0) ASN__ENCODE_FAILED;
 
-        ASN_DEBUG("Encoding %zd of %zu", maySave, size_in_units);
+        ASN_DEBUG("Encoding %zd of %zu%s", may_save, size_in_units,
+                  need_eom ? ",+EOM" : "");
 
-        ret = OCTET_STRING_per_put_characters(po, buf, maySave, bpc, unit_bits,
+        ret = OCTET_STRING_per_put_characters(po, buf, may_save, bpc, unit_bits,
                                               cval->lower_bound,
                                               cval->upper_bound, pc);
         if(ret) ASN__ENCODE_FAILED;
 
-        buf += maySave * bpc;
-        size_in_units -= maySave;
-        assert(!(maySave & 0x07) || !size_in_units);
-    }
+        buf += may_save * bpc;
+        size_in_units -= may_save;
+        assert(!(may_save & 0x07) || !size_in_units);
+        if(need_eom && uper_put_length(po, 0, 0))
+            ASN__ENCODE_FAILED; /* End of Message length */
+    } while(size_in_units);
 
     ASN__ENCODED_OK(er);
 }

skeletons/constr_SEQUENCE_OF.c

@@ -190,7 +190,7 @@ SEQUENCE_OF_encode_uper(asn_TYPE_descriptor_t *td,
 		if(ct && ct->effective_bits >= 0) {
 			mayEncode = list->count;
 		} else {
-			mayEncode = uper_put_length(po, list->count - seq);
+			mayEncode = uper_put_length(po, list->count - seq, 0);
 			if(mayEncode < 0) ASN__ENCODE_FAILED;
 		}
 

skeletons/per_opentype.c

@@ -27,33 +27,38 @@ static asn_dec_rval_t uper_sot_suck(const asn_codec_ctx_t *,
  */
 int
 uper_open_type_put(asn_TYPE_descriptor_t *td, const asn_per_constraints_t *constraints, void *sptr, asn_per_outp_t *po) {
-	void *buf;
-	void *bptr;
-	ssize_t size;
-	size_t toGo;
-
-	ASN_DEBUG("Open type put %s ...", td->name);
-
-	size = uper_encode_to_new_buffer(td, constraints, sptr, &buf);
-	if(size <= 0) return -1;
-
-	for(bptr = buf, toGo = size; toGo;) {
-		ssize_t maySave = uper_put_length(po, toGo);
-		ASN_DEBUG("Prepending length %d to %s and allowing to save %d",
-			(int)size, td->name, (int)maySave);
-		if(maySave < 0) break;
-		if(per_put_many_bits(po, bptr, maySave * 8)) break;
-		bptr = (char *)bptr + maySave;
-		toGo -= maySave;
-	}
-
-	FREEMEM(buf);
-	if(toGo) return -1;
-
-	ASN_DEBUG("Open type put %s of length %ld + overhead (1byte?)",
-		td->name, (long)size);
-
-	return 0;
+    void *buf;
+    void *bptr;
+    ssize_t size;
+
+    ASN_DEBUG("Open type put %s ...", td->name);
+
+    size = uper_encode_to_new_buffer(td, constraints, sptr, &buf);
+    if(size <= 0) return -1;
+
+    ASN_DEBUG("Open type put %s of length %zd + overhead (1byte?)", td->name,
+              size);
+
+    bptr = buf;
+    do {
+        int need_eom = 0;
+        ssize_t maySave = uper_put_length(po, size, &need_eom);
+        ASN_DEBUG("Prepending length %zd to %s and allowing to save %d", size,
+                  td->name, (int)maySave);
+        if(maySave < 0) break;
+        if(per_put_many_bits(po, bptr, maySave * 8)) break;
+        bptr = (char *)bptr + maySave;
+        size -= maySave;
+        if(need_eom && uper_put_length(po, 0, 0)) {
+            FREEMEM(buf);
+            return -1;
+        }
+    } while(size);
+
+    FREEMEM(buf);
+    if(size) return -1;
+
+    return 0;
 }
 
 static asn_dec_rval_t

skeletons/per_support.c

@@ -177,17 +177,26 @@ int uper_put_constrained_whole_number_u(asn_per_outp_t *po, unsigned long v, int
  * Put the length "n" (or part of it) into the stream.
  */
 ssize_t
-uper_put_length(asn_per_outp_t *po, size_t length) {
+uper_put_length(asn_per_outp_t *po, size_t length, int *need_eom) {
+    int dummy = 0;
+    if(!need_eom) need_eom = &dummy;
 
-    if(length <= 127)	/* #11.9.3.6 */
+    if(length <= 127) {	/* #11.9.3.6 */
+        *need_eom = 0;
         return per_put_few_bits(po, length, 8)
             ? -1 : (ssize_t)length;
-    else if(length < 16384)	/* #10.9.3.7 */
+    } else if(length < 16384) { /* #10.9.3.7 */
+        *need_eom = 0;
         return per_put_few_bits(po, length|0x8000, 16)
             ? -1 : (ssize_t)length;
+    }
 
+    *need_eom = 0 == (length & 16383);
     length >>= 14;
-    if(length > 4) length = 4;
+    if(length > 4) {
+        *need_eom = 0;
+        length = 4;
+    }
 
     return per_put_few_bits(po, 0xC0 | length, 8)
             ? -1 : (ssize_t)(length << 14);
@@ -202,18 +211,19 @@ uper_put_length(asn_per_outp_t *po, size_t length) {
  */
 int
 uper_put_nslength(asn_per_outp_t *po, size_t length) {
+    if(length <= 64) {
+        /* #11.9.3.4 */
+        if(length == 0) return -1;
+        return per_put_few_bits(po, length - 1, 7) ? -1 : 0;
+    } else {
+        int need_eom = 0;
+        if(uper_put_length(po, length, &need_eom) != (ssize_t)length
+           || need_eom) {
+            /* This might happen in case of >16K extensions */
+            return -1;
+        }
+    }
 
-	if(length <= 64) {
-		/* #11.9.3.4 */
-		if(length == 0) return -1;
-		return per_put_few_bits(po, length-1, 7) ? -1 : 0;
-	} else {
-		if(uper_put_length(po, length) != (ssize_t)length) {
-			/* This might happen in case of >16K extensions */
-			return -1;
-		}
-	}
-
-	return 0;
+    return 0;
 }
 

skeletons/per_support.h

@@ -75,11 +75,14 @@ int uper_put_constrained_whole_number_u(asn_per_outp_t *po, unsigned long v, int
 
 /*
  * X.691 (08/2015) #11.9 "General rules for encoding a length determinant"
- * Put the length "n" to the Unaligned PER stream.
+ * Put the length "whole_length" to the Unaligned PER stream.
+ * If (opt_need_eom) is given, it will be set to 1 if final 0-length is needed.
+ * In that case, invoke uper_put_length(po, 0, 0) after encoding the last block.
  * This function returns the number of units which may be flushed
  * in the next units saving iteration.
  */
-ssize_t uper_put_length(asn_per_outp_t *po, size_t whole_length);
+ssize_t uper_put_length(asn_per_outp_t *po, size_t whole_length,
+                        int *opt_need_eom);
 
 /*
  * Put the normally small length "n" to the Unaligned PER stream.

tests/tests-randomized/bundles/03-BIT-STRING-bundle.txt

@@ -17,3 +17,9 @@ T ::= BIT STRING { foo(2147483648), baz(2147483647) } (SIZE(32))
 T ::= BIT STRING { foo(2147483648), baz(2147483647) } (SIZE(31,...))
 T ::= BIT STRING { foo(2147483648), baz(2147483647) } (SIZE(0..32))
 T ::= BIT STRING { foo(2147483648), baz(2147483647) } (SIZE(0..31,...))
+T ::= BIT STRING { foo(0) } (SIZE(65535))       -- RMAX=65540
+T ::= BIT STRING { foo(0) } (SIZE(65536))       -- RMAX=65540
+T ::= BIT STRING { foo(0) } (SIZE(65537))       -- RMAX=65540
+T ::= BIT STRING { foo(0) } (SIZE(65535,...))   -- RMAX=65540
+T ::= BIT STRING { foo(0) } (SIZE(65536,...))   -- RMAX=65540
+T ::= BIT STRING { foo(0) } (SIZE(65537,...))   -- RMAX=65540

tests/tests-randomized/bundles/04-VisibleString-bundle.txt

@@ -16,11 +16,12 @@ T ::= VisibleString (SIZE(1..127))
 T ::= VisibleString (SIZE(1..128))
 T ::= VisibleString (SIZE(1..129))
 T ::= VisibleString (SIZE(5) INTERSECTION FROM("A".."Z"))
-RMAX=64000 VisibleString (SIZE(64000))   -- Length is not encoded, #11.9.3.3
-RMAX=33000 T ::= VisibleString (SIZE(32000..32002))
-RMAX=33000 T ::= VisibleString (SIZE(32000..32002)) (FROM("A".."B"))
-RMAX=33000 T ::= VisibleString (SIZE(32000..32002,...)) (FROM("A".."B"))
-RMAX=65536 T ::= VisibleString (SIZE(65530..65535))
-RMAX=65536 T ::= VisibleString (SIZE(65530..65536))
 T ::= VisibleString (SIZE(4..6) INTERSECTION (FROM("A".."B")))
 T ::= VisibleString (SIZE(4..6,...) INTERSECTION (FROM("A".."B")))
+VisibleString (SIZE(64000))                 -- RMAX=64000, #11.9.3.3
+T ::= VisibleString (SIZE(32000..32002))    -- RMAX=33000
+T ::= VisibleString (SIZE(32000..32002)) (FROM("A".."B"))       -- RMAX=33000
+T ::= VisibleString (SIZE(32000..32002,...)) (FROM("A".."B"))   -- RMAX=33000
+T ::= VisibleString (SIZE(65530..65535))    -- RMAX=65536
+T ::= VisibleString (SIZE(65530..65536))    -- RMAX=65536
+T ::= VisibleString (SIZE(65535..65550))    -- RMAX=66000

tests/tests-randomized/bundles/README

@@ -14,9 +14,9 @@ contstraints that are intended to affect encoding and parsing.
 
  * By default, the random value generator attempts to generate values
    limited to very roughly to around 128 bytes. If huge values are desired
-   (perhaps due to large constraints), the RMAX=<size> prefix can be specified
-   on a line:
+   (perhaps due to large constraints), the RMAX=<size> setting can be specified
+   in the ASN.1 comments:
 
-        RMAX=64000 T ::= VisibleString (SIZE(64000))
+        T ::= VisibleString (SIZE(64000))    -- RMAX=64000
    
 

tests/tests-randomized/check-bundles.sh

@@ -148,12 +148,11 @@ asn_compile() {
     local asn="$1"
     shift
 
-    # Create "INTEGER (1..2)" from "RMAX=5 T ::= INTEGER (1..2) -- Comment"
+    # Create "INTEGER (1..2)" from "T ::= INTEGER (1..2) -- RMAX=5"
     local short_asn=$(echo "$asn" | sed -e 's/ *--.*//;s/RMAX=[^ ]* //;')
     if [ $(echo "$short_asn" | grep -c "::=") = 1 ]; then
         short_asn=$(echo "$short_asn" | sed -e 's/.*::= *//')
     fi
-    asn=$(echo "$asn" | sed -e 's/RMAX=[^ ]* //;')
 
     test ! -f Makefile.am   # Protection from accidental clobbering
     echo "Test DEFINITIONS ::= BEGIN $asn" > test.asn1

tests/tests-skeletons/Makefile.am

@@ -15,6 +15,7 @@ check_PROGRAMS =            \
     check-OER-support       \
     check-OER-INTEGER       \
     check-OER-NativeEnumerated \
+    check-PER-support       \
     check-PER-UniversalString  \
     check-PER-INTEGER
 

tests/tests-skeletons/check-PER-support.c

+#include <assert.h>
+#include <per_support.h>
+
+static void put(asn_per_outp_t *po, size_t length) {
+    fprintf(stderr, "put(%zd)\n", length);
+    do {
+        int need_eom = 123;
+        ssize_t may_write = uper_put_length(po, length, &need_eom);
+        fprintf(stderr, "  put %zu\n", may_write);
+        assert(may_write >= 0);
+        assert(may_write <= length);
+        assert(need_eom != 123);
+        length -= may_write;
+        if(need_eom) {
+            assert(length == 0);
+            if(uper_put_length(po, 0, 0)) {
+                assert(!"Unreachable");
+            }
+            fprintf(stderr, "  put EOM 0\n");
+        }
+    } while(length);
+    fprintf(stderr, "put(...) in %zu bits\n", po->nboff);
+    assert(po->nboff != 0);
+    assert(po->flushed_bytes == 0);
+}
+
+static size_t get(asn_per_outp_t *po) {
+    asn_bit_data_t data;
+    memset(&data, 0, sizeof(data));
+    data.buffer = po->tmpspace;
+    data.nboff = 0;
+    data.nbits = 8 * (po->buffer - po->tmpspace) + po->nboff;
+
+    fprintf(stderr, "get(): %s\n", asn_bit_data_string(&data));
+
+    size_t length = 0;
+    int repeat = 0;
+    do {
+        ssize_t n = uper_get_length(&data, -1, 0, &repeat);
+        fprintf(stderr, "  get = %zu +%zd\n", length, n);
+        assert(n >= 0);
+        length += n;
+    } while(repeat);
+    fprintf(stderr, "get() = %zu\n", length);
+
+    return length;
+}
+
+static void
+check_round_trip(size_t length) {
+    fprintf(stderr, "\nRound-trip for %zu\n", length);
+    asn_per_outp_t po;
+
+    memset(&po, 0, sizeof(po));
+    po.buffer = po.tmpspace;
+    po.nbits = 8 * sizeof(po.tmpspace);
+
+    put(&po, length);
+    size_t recovered = get(&po);
+
+    assert(recovered == length);
+}
+
+int main() {
+
+    check_round_trip(0);
+    check_round_trip(1);
+    check_round_trip(127);
+    check_round_trip(128);
+    check_round_trip(129);
+    check_round_trip(255);
+    check_round_trip(256);
+    check_round_trip(65534);
+    check_round_trip(65535);
+    check_round_trip(65536);
+    check_round_trip(65538);
+    check_round_trip(128000);
+    for(size_t i = 1; i < 10; i++) {
+        check_round_trip(i*16384 - 1);
+        check_round_trip(i*16384);
+        check_round_trip(i*16384 + 1);
+    }
+
+}
+

tests/tests-skeletons/check-PER.c

-#include <stdio.h>
-#include <assert.h>
-
-#include <asn_bit_data.c>
-#include <per_support.c>
-#include <per_support.h>
-
-static void
-check_per_decoding() {
-	uint8_t buf[] = { 0xB7, 0x19, 0x2F, 0xEE, 0xAD };
-	uint8_t tmpbuf[10];
-	int32_t z;
-	asn_per_data_t pos;
-	memset(&pos, 0, sizeof(pos));
-
-	pos.buffer = buf;
-	pos.nboff = 0;
-	pos.nbits = sizeof(buf) * 8;
-
-	z = per_get_few_bits(&pos, 32);
-	assert(z == -1);
-	assert(pos.nbits == sizeof(buf) * 8);
-
-	z = per_get_few_bits(&pos, 0);
-	assert(z == 0);
-	assert(pos.nboff == 0);
-	assert(pos.nbits == sizeof(buf) * 8);
-
-	z = per_get_few_bits(&pos, 1);
-	assert(z == 1);
-	assert(pos.nboff == 1);
-	assert(pos.nbits == sizeof(buf) * 8);
-
-	z = per_get_few_bits(&pos, 2);
-	assert(z == 1);
-	assert(pos.nboff == 3);
-	assert(pos.nbits == sizeof(buf) * 8);
-
-	z = per_get_few_bits(&pos, 2);
-	assert(z == 2);
-	assert(pos.nboff == 5);
-	assert(pos.nbits == sizeof(buf) * 8);
-
-	z = per_get_few_bits(&pos, 3);
-	assert(z == 7);
-	assert(pos.nboff == 8);
-	assert(pos.nbits == sizeof(buf) * 8);
-
-	z = per_get_few_bits(&pos, 8);
-	assert(z == 0x19);
-	assert(pos.nboff == 8);
-	assert(pos.nbits == (sizeof(buf) - 1) * 8);
-
-	z = per_get_few_bits(&pos, 1);
-	assert(z == 0);
-	assert(pos.nboff == 1);
-	assert(pos.nbits == (sizeof(buf) - 2) * 8);
-
-	z = per_get_few_bits(&pos, 3);
-	assert(z == 2);
-	assert(pos.nboff == 4);
-	assert(pos.nbits == (sizeof(buf) - 2) * 8);
-
-	z = per_get_few_bits(&pos, 8);
-	assert(z == 254);
-	assert(pos.nboff == 12);
-
-	pos.buffer = buf;
-	pos.nboff = 2;
-	pos.nbits = sizeof(buf) * 8;
-	z = per_get_few_bits(&pos, 24);
-	assert(z == 14443711);
-
-	pos.buffer = (unsigned char *)"\001";
-	pos.nboff = 7;
-	pos.nbits = 7;
-	z = per_get_few_bits(&pos, 1);
-	assert(pos.nboff == 7);
-	assert(pos.nbits == 7);
-	assert(z == -1);
-
-	pos.buffer = (unsigned char *)"\001";
-	pos.nboff = 7;
-	pos.nbits = 8;
-	z = per_get_few_bits(&pos, 1);
-	assert(pos.nboff == 8);
-	assert(pos.nbits == 8);
-	assert(z == 1);
-
-	pos.buffer = (unsigned char *)"\000";
-	pos.nboff = 7;
-	pos.nbits = 8;
-	z = per_get_few_bits(&pos, 1);
-	assert(pos.nboff == 8);
-	assert(pos.nbits == 8);
-	assert(z == 0);
-	z = per_get_few_bits(&pos, 1);
-	assert(pos.nboff == 8);
-	assert(pos.nbits == 8);
-	assert(z == -1);
-
-	pos.buffer = (unsigned char *)"\000";
-	pos.nboff = 7;
-	pos.nbits = 9;
-	z = per_get_few_bits(&pos, 1);
-	assert(pos.nboff == 8);
-	assert(pos.nbits == 9);
-	assert(z == 0);
-	z = per_get_few_bits(&pos, 1);
-	assert(pos.nboff == 1);
-	assert(pos.nbits == 1);
-	assert(z == 0);
-
-	pos.buffer = (unsigned char *)"\001";
-	pos.nboff = 7;
-	pos.nbits = 9;
-	z = per_get_few_bits(&pos, 1);
-	assert(pos.nboff == 8);
-	assert(pos.nbits == 9);
-	assert(z == 1);
-	z = per_get_few_bits(&pos, 1);
-	assert(pos.nboff == 1);
-	assert(pos.nbits == 1);
-	assert(z == 0);
-
-	/* Get full 31-bit range */
-	pos.buffer = buf;
-	pos.nboff = 7;
-	pos.nbits = sizeof(buf) * 8;
-	z = per_get_few_bits(&pos, 31);
-	assert(z == 1179384747);
-
-	/* Get a bit shifted range */
-	pos.buffer = buf;
-	pos.nboff = 6;
-	pos.nbits = sizeof(buf) * 8;
-	z = per_get_few_bits(&pos, 31);
-	assert(z == 1663434197);
-
-	pos.buffer = buf;
-	pos.nboff = 0;
-	pos.nbits = sizeof(buf) * 8;
-	z = per_get_many_bits(&pos, tmpbuf, 0, sizeof(buf) * 8);
-	assert(z == 0);
-	assert(buf[0] == tmpbuf[0]);
-	assert(buf[1] == tmpbuf[1]);
-	assert(buf[2] == tmpbuf[2]);
-	assert(buf[3] == tmpbuf[3]);
-	assert(buf[4] == tmpbuf[4]);
-
-	pos.buffer = buf;
-	pos.nboff = 1;
-	pos.nbits = sizeof(buf) * 8;
-	z = per_get_many_bits(&pos, tmpbuf, 0, sizeof(buf) * 8);
-	assert(z == -1);
-
-	pos.buffer = buf;
-	pos.nboff = 1;
-	pos.nbits = sizeof(buf) * 8;
-	z = per_get_many_bits(&pos, tmpbuf, 0, sizeof(buf) * 8 - 1);
-	assert(z == 0);
-	assert(tmpbuf[0] == 110);
-	assert(tmpbuf[1] == 50);
-	assert(tmpbuf[2] == 95);
-	assert(tmpbuf[3] == 221);
-	assert(tmpbuf[4] == 90);
-
-	pos.buffer = buf;
-	pos.nboff = 1;
-	pos.nbits = sizeof(buf) * 8;
-	z = per_get_many_bits(&pos, tmpbuf, 1, sizeof(buf) * 8 - 1);
-	assert(z == 0);
-	assert(tmpbuf[0] == 55);
-	assert(tmpbuf[0] != buf[0]);
-	assert(tmpbuf[1] == buf[1]);
-	assert(tmpbuf[2] == buf[2]);
-	assert(tmpbuf[3] == buf[3]);
-	assert(tmpbuf[4] == buf[4]);
-}
-
-static int Ignore(const void *data, size_t size, void *op_key) {
-    (void)data;
-    (void)size;
-    (void)op_key;
-	return 0;
-}
-
-static void
-check_per_encoding() {
-	asn_per_outp_t po;
-	int ret;
-
-	po.buffer = po.tmpspace;
-	po.nboff = 0;
-	po.nbits = 0;
-	po.output = Ignore;
-	po.op_key = 0;
-	po.tmpspace[0] = 0xff;
-
-	ret = per_put_few_bits(&po, 0, 0);
-	assert(ret == 0);
-	assert(po.nboff == 0);
-	assert(po.buffer == po.tmpspace);
-	assert(po.tmpspace[0] == 0xff);
-
-	ret = per_put_few_bits(&po, 0, 1);
-	assert(ret == 0);
-	assert(po.nboff == 1);
-	assert(po.nbits == 8 * sizeof(po.tmpspace));
-	assert(po.buffer == po.tmpspace);
-	assert(po.tmpspace[0] == 0x00);
-
-	ret = per_put_few_bits(&po, 1, 1);
-	assert(ret == 0);
-	assert(po.nboff == 2);
-	assert(po.nbits == 8 * sizeof(po.tmpspace));
-	assert(po.buffer == po.tmpspace);
-	assert(po.tmpspace[0] == 0x40);
-
-	ret = per_put_few_bits(&po, 1, 1);
-	assert(ret == 0);
-	assert(po.nboff == 3);
-	assert(po.nbits == 8 * sizeof(po.tmpspace));
-	assert(po.buffer == po.tmpspace);
-	assert(po.tmpspace[0] == 0x60);
-
-	ret = per_put_few_bits(&po, 15, 5);
-	assert(ret == 0);
-	assert(po.nboff == 8);
-	assert(po.nbits == 8 * sizeof(po.tmpspace));
-	assert(po.buffer == po.tmpspace);
-	assert(po.tmpspace[0] == 0x6F);
-
-	ret = per_put_few_bits(&po, 0xf0ff, 16);
-	assert(ret == 0);
-	assert(po.nboff == 16);
-	assert(po.nbits == 8 * sizeof(po.tmpspace) - 8);
-	assert(po.buffer == po.tmpspace + 1);
-	assert(po.tmpspace[0] == 0x6F);
-	assert(po.tmpspace[1] == 0xf0);
-	assert(po.tmpspace[2] == 0xff);
-
-	po.nboff--;
-
-	ret = per_put_few_bits(&po, 2, 1);
-	assert(ret == 0);
-	assert(po.nboff == 8);
-	assert(po.nbits == 8 * sizeof(po.tmpspace) - 16);
-	assert(po.buffer == po.tmpspace + 2);
-	assert(po.tmpspace[0] == 0x6F);
-	assert(po.tmpspace[1] == 0xf0);
-	assert(po.tmpspace[2] == 0xfe);
-
-	ret = per_put_few_bits(&po, 2, 32);
-	assert(ret == -1);
-
-	ret = per_put_few_bits(&po, 2, -1);
-	assert(ret == -1);
-
-	ret = per_put_few_bits(&po, -1, 31);
-	assert(ret == 0);
-	assert(po.nboff == 31);
-	assert(po.nbits == 8 * sizeof(po.tmpspace) - 24);
-	assert(po.buffer == po.tmpspace + 3);
-	assert(po.tmpspace[0] == 0x6F);
-	assert(po.tmpspace[1] == 0xf0);
-	assert(po.tmpspace[2] == 0xfe);
-	assert(po.tmpspace[3] == 0xff);
-	assert(po.tmpspace[4] == 0xff);
-	assert(po.tmpspace[5] == 0xff);
-	assert(po.tmpspace[6] == 0xfe);
-
-}
-
-/*
- * Add N bits after P bits. Should result in N+P bits added.
- */
-static void
-check_per_encoding_auto() {
-    int prior, next;
-    int ret, i;
-
-    for(prior = 0; prior <= 31; prior++) {
-      for(next = 0; next <= 31; next++) {
-        asn_per_outp_t po;
-        po.buffer = po.tmpspace;
-        po.nboff = 0;
-        po.nbits = 0;
-        po.output = Ignore;
-        po.op_key = 0;
-        po.tmpspace[0] = 0xff;
-
-        ret = per_put_few_bits(&po, -1, prior);
-        assert(ret == 0);
-
-		ASN_DEBUG(" (out{nboff=%d,nbits=%d,buf_offset=%d})", (int)po.nboff, (int)po.nbits, (int)(po.buffer - po.tmpspace));
-
-        ret = per_put_few_bits(&po, -1, next);
-        assert(ret == 0);
-
-		ASN_DEBUG(" (out{nboff=%d,nbits=%d,buf_offset=%d})", (int)po.nboff, (int)po.nbits, (int)(po.buffer - po.tmpspace));
-
-		ASN_DEBUG("Putting %d + %d bits (%d/%d), got %d bytes and %d bits",
-            prior, next, (prior + next) / 8, (prior + next) % 8,
-            (int)(po.buffer - po.tmpspace), (int)po.nboff);
-        assert((po.buffer - po.tmpspace) * 8 + po.nboff == (size_t)(prior + next));
-        for(i = 0; i < (po.buffer - po.tmpspace); i++)
-            assert(po.tmpspace[0] == (unsigned char)-1);
-      }
-    }
-}
-
-static void
-check_per_encoding_sweep_with(uint8_t buf[], int already_bits, int add_bits) {
-	size_t buf_size = 8;
-	asn_per_data_t pos;
-	asn_per_outp_t out;
-	int32_t d_already;
-	int32_t d_add;
-	int32_t d_left;
-	int left_bits;
-
-	memset(&pos, 0, sizeof(pos));
-	pos.buffer = buf;
-	pos.nboff = 0;
-	pos.nbits = buf_size * 8;
-
-	memset(&out, 0, sizeof(out));
-	out.buffer = out.tmpspace;
-	out.nbits = 8 * sizeof(out.tmpspace);
-	assert(sizeof(out.tmpspace) >= buf_size);
-	memcpy(out.buffer, buf, buf_size);
-
-	d_already = per_get_few_bits(&pos, already_bits);
-	d_add = per_get_few_bits(&pos, add_bits);
-
-	per_put_few_bits(&out, d_already, already_bits);
-	per_put_few_bits(&out, d_add, add_bits);
-	if(out.nboff % 8) {
-		left_bits = 8 - (out.nboff % 8);
-		d_left = per_get_few_bits(&pos, left_bits);
-	} else {
-		left_bits = 0;
-		d_left = 0;
-	}
-	per_put_few_bits(&out, d_left, left_bits);
-	assert(0 == (out.nboff % 8));
-
-	if(0 != memcmp(out.tmpspace, buf, buf_size)) {
-		printf("IN: ");
-		for(size_t i = 0; i < buf_size; i++)
-			printf(" %02x", buf[i]);
-		printf("\nOUT:");
-		for(size_t i = 0; i < buf_size; i++)
-			printf(" %02x", out.tmpspace[i]);
-		printf(" (out{nboff=%d,left=%d,%02x})\n", (int)out.nboff, left_bits, (int)d_left);
-		assert(0 == memcmp(out.tmpspace, buf, buf_size));
-	}
-}
-
-static void
-check_per_encoding_sweep() {
-	uint8_t buf[3][8] = {
-		{ 0x55, 0xAA, 0x55, 0xAA, 0x55, 0xAA, 0x55, 0xAA },
-		{ 0xB7, 0x19, 0x2F, 0xEE, 0xAD, 0x11, 0xAA, 0x55 },
-		{ 0xEE, 0xAD, 0x11, 0xAA, 0x55, 0xB7, 0x19, 0x2F }
-	};
-	int already_bits;
-	int add_bits;
-	int buf_idx;
-
-	for(buf_idx = 0; buf_idx < 3; buf_idx++) {
-	 for(already_bits = 0; already_bits < 24; already_bits++) {
-	  for(add_bits = 0; add_bits <= 31; add_bits++) {
-	   /*fprintf(stderr, "PER %d += %d\n", already_bits, add_bits);*/
-	   check_per_encoding_sweep_with(buf[buf_idx], already_bits, add_bits);
-	  }
-	 }
-	}
-}
-
-int
-main() {
-	check_per_decoding();
-	check_per_encoding();
-	check_per_encoding_auto();
-	check_per_encoding_sweep();
-	return 0;
-}