Add version 0.5.0

Change-Id: Ic052ea806f728c7e437038b1809f84a47af90011
Signed-off-by: Peter Szilagyi <peter.3.szilagyi@nokia.com>
diff --git a/e2ap/lib/per_support.c b/e2ap/lib/per_support.c
new file mode 100644
index 0000000..2285677
--- /dev/null
+++ b/e2ap/lib/per_support.c
@@ -0,0 +1,489 @@
+/*
+ * Copyright (c) 2005-2017 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#include <asn_system.h>
+#include <asn_internal.h>
+#include <per_support.h>
+
+/*
+ * X.691-201508 #10.9 General rules for encoding a length determinant.
+ * Get the optionally constrained length "n" from the stream.
+ */
+ssize_t
+uper_get_length(asn_per_data_t *pd, int ebits, size_t lower_bound,
+                int *repeat) {
+    ssize_t value;
+
+    *repeat = 0;
+
+    /* #11.9.4.1 Encoding if constrained (according to effective bits) */
+    if(ebits >= 0 && ebits <= 16) {
+        value = per_get_few_bits(pd, ebits);
+        if(value >= 0) value += lower_bound;
+        return value;
+    }
+
+	value = per_get_few_bits(pd, 8);
+    if((value & 0x80) == 0) { /* #11.9.3.6 */
+        return (value & 0x7F);
+    } else if((value & 0x40) == 0) { /* #11.9.3.7 */
+        /* bit 8 ... set to 1 and bit 7 ... set to zero */
+        value = ((value & 0x3f) << 8) | per_get_few_bits(pd, 8);
+        return value; /* potential -1 from per_get_few_bits passes through. */
+    } else if(value < 0) {
+        ASN_DEBUG("END of stream reached for PER");
+        return -1;
+    }
+    value &= 0x3f; /* this is "m" from X.691, #11.9.3.8 */
+    if(value < 1 || value > 4) {
+        return -1; /* Prohibited by #11.9.3.8 */
+    }
+    *repeat = 1;
+    return (16384 * value);
+}
+
+/*
+ * Get the normally small length "n".
+ * This procedure used to decode length of extensions bit-maps
+ * for SET and SEQUENCE types.
+ */
+ssize_t
+uper_get_nslength(asn_per_data_t *pd) {
+	ssize_t length;
+
+	ASN_DEBUG("Getting normally small length");
+
+	if(per_get_few_bits(pd, 1) == 0) {
+		length = per_get_few_bits(pd, 6) + 1;
+		if(length <= 0) return -1;
+		ASN_DEBUG("l=%d", (int)length);
+		return length;
+	} else {
+		int repeat;
+		length = uper_get_length(pd, -1, 0, &repeat);
+		if(length >= 0 && !repeat) return length;
+		return -1; /* Error, or do not support >16K extensions */
+	}
+}
+
+/*
+ * Get the normally small non-negative whole number.
+ * X.691, #10.6
+ */
+ssize_t
+uper_get_nsnnwn(asn_per_data_t *pd) {
+	ssize_t value;
+
+	value = per_get_few_bits(pd, 7);
+	if(value & 64) {	/* implicit (value < 0) */
+		value &= 63;
+		value <<= 2;
+		value |= per_get_few_bits(pd, 2);
+		if(value & 128)	/* implicit (value < 0) */
+			return -1;
+		if(value == 0)
+			return 0;
+		if(value >= 3)
+			return -1;
+		value = per_get_few_bits(pd, 8 * value);
+		return value;
+	}
+
+	return value;
+}
+
+/*
+ * X.691-11/2008, #11.6
+ * Encoding of a normally small non-negative whole number
+ */
+int
+uper_put_nsnnwn(asn_per_outp_t *po, int n) {
+	int bytes;
+
+	if(n <= 63) {
+		if(n < 0) return -1;
+		return per_put_few_bits(po, n, 7);
+	}
+	if(n < 256)
+		bytes = 1;
+	else if(n < 65536)
+		bytes = 2;
+	else if(n < 256 * 65536)
+		bytes = 3;
+	else
+		return -1;	/* This is not a "normally small" value */
+	if(per_put_few_bits(po, bytes, 8))
+		return -1;
+
+	return per_put_few_bits(po, n, 8 * bytes);
+}
+
+
+/* X.691-2008/11, #11.5.6 -> #11.3 */
+int uper_get_constrained_whole_number(asn_per_data_t *pd, unsigned long *out_value, int nbits) {
+	unsigned long lhalf;    /* Lower half of the number*/
+	long half;
+
+	if(nbits <= 31) {
+		half = per_get_few_bits(pd, nbits);
+		if(half < 0) return -1;
+		*out_value = half;
+		return 0;
+	}
+
+	if((size_t)nbits > 8 * sizeof(*out_value))
+		return -1;  /* RANGE */
+
+	half = per_get_few_bits(pd, 31);
+	if(half < 0) return -1;
+
+	if(uper_get_constrained_whole_number(pd, &lhalf, nbits - 31))
+		return -1;
+
+	*out_value = ((unsigned long)half << (nbits - 31)) | lhalf;
+	return 0;
+}
+
+
+/* X.691-2008/11, #11.5.6 -> #11.3 */
+int
+uper_put_constrained_whole_number_u(asn_per_outp_t *po, unsigned long v,
+                                    int nbits) {
+    if(nbits <= 31) {
+        return per_put_few_bits(po, v, nbits);
+    } else {
+        /* Put higher portion first, followed by lower 31-bit */
+        if(uper_put_constrained_whole_number_u(po, v >> 31, nbits - 31))
+            return -1;
+        return per_put_few_bits(po, v, 31);
+    }
+}
+
+/*
+ * X.691 (08/2015) #11.9 "General rules for encoding a length determinant"
+ * Put the length "n" (or part of it) into the stream.
+ */
+ssize_t
+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 */
+        *need_eom = 0;
+        return per_put_few_bits(po, length, 8)
+            ? -1 : (ssize_t)length;
+    } 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) {
+        *need_eom = 0;
+        length = 4;
+    }
+
+    return per_put_few_bits(po, 0xC0 | length, 8)
+            ? -1 : (ssize_t)(length << 14);
+
+}
+
+
+/*
+ * Put the normally small length "n" into the stream.
+ * This procedure used to encode length of extensions bit-maps
+ * for SET and SEQUENCE types.
+ */
+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;
+        }
+    }
+
+    return 0;
+}
+
+static int
+per__long_range(long lb, long ub, unsigned long *range_r) {
+    unsigned long bounds_range;
+    if((ub < 0) == (lb < 0)) {
+        bounds_range = ub - lb;
+    } else if(lb < 0) {
+        assert(ub >= 0);
+        bounds_range = 1 + ((unsigned long)ub + (unsigned long)-(lb + 1));
+    } else {
+        assert(!"Unreachable");
+        return -1;
+    }
+    *range_r = bounds_range;
+    return 0;
+}
+
+int
+per_long_range_rebase(long v, long lb, long ub, unsigned long *output) {
+    unsigned long range;
+
+    assert(lb <= ub);
+
+    if(v < lb || v > ub || per__long_range(lb, ub, &range) < 0) {
+        /* Range error. */
+        return -1;
+    }
+
+    /*
+     * Fundamentally what we're doing is returning (v-lb).
+     * However, this triggers undefined behavior when the word width
+     * of signed (v) is the same as the size of unsigned (*output).
+     * In practice, it triggers the UndefinedSanitizer. Therefore we shall
+     * compute the ranges accurately to avoid C's undefined behavior.
+     */
+    if((v < 0) == (lb < 0)) {
+        *output = v-lb;
+        return 0;
+    } else if(v < 0) {
+        unsigned long rebased = 1 + (unsigned long)-(v+1) + (unsigned long)lb;
+        assert(rebased <= range);   /* By construction */
+        *output = rebased;
+        return 0;
+    } else if(lb < 0) {
+        unsigned long rebased = 1 + (unsigned long)-(lb+1) + (unsigned long)v;
+        assert(rebased <= range);   /* By construction */
+        *output = rebased;
+        return 0;
+    } else {
+        assert(!"Unreachable");
+        return -1;
+    }
+}
+
+int
+per_long_range_unrebase(unsigned long inp, long lb, long ub, long *outp) {
+    unsigned long range;
+
+    if(per__long_range(lb, ub, &range) != 0) {
+        return -1;
+    }
+
+    if(inp > range) {
+        /*
+         * We can encode something in the given number of bits that technically
+         * exceeds the range. This is an avenue for security errors,
+         * so we don't allow that.
+         */
+        return -1;
+    }
+
+    if(inp <= LONG_MAX) {
+        *outp = (long)inp + lb;
+    } else {
+        *outp = (lb + LONG_MAX + 1) + (long)((inp - LONG_MAX) - 1);
+    }
+
+    return 0;
+}
+
+int32_t
+aper_get_align(asn_per_data_t *pd) {
+
+	if(pd->nboff & 0x7) {
+		ASN_DEBUG("Aligning %ld bits", 8 - ((unsigned long)pd->nboff & 0x7));
+		return per_get_few_bits(pd, 8 - (pd->nboff & 0x7));
+	}
+	return 0;
+}
+
+ssize_t
+aper_get_length(asn_per_data_t *pd, int range, int ebits, int *repeat) {
+	ssize_t value;
+
+	*repeat = 0;
+
+	if (range <= 65536 && range >= 0)
+		return aper_get_nsnnwn(pd, range);
+
+	if (aper_get_align(pd) < 0)
+		return -1;
+
+	if(ebits >= 0) return per_get_few_bits(pd, ebits);
+
+	value = per_get_few_bits(pd, 8);
+	if(value < 0) return -1;
+	if((value & 128) == 0)  /* #10.9.3.6 */
+		return (value & 0x7F);
+	if((value & 64) == 0) { /* #10.9.3.7 */
+		value = ((value & 63) << 8) | per_get_few_bits(pd, 8);
+		if(value < 0) return -1;
+		return value;
+	}
+	value &= 63;	/* this is "m" from X.691, #10.9.3.8 */
+	if(value < 1 || value > 4)
+		return -1;
+	*repeat = 1;
+	return (16384 * value);
+}
+
+ssize_t
+aper_get_nslength(asn_per_data_t *pd) {
+	ssize_t length;
+
+	ASN_DEBUG("Getting normally small length");
+
+	if(per_get_few_bits(pd, 1) == 0) {
+		length = per_get_few_bits(pd, 6) + 1;
+		if(length <= 0) return -1;
+		ASN_DEBUG("l=%ld", length);
+		return length;
+	} else {
+		int repeat;
+		length = aper_get_length(pd, -1, -1, &repeat);
+		if(length >= 0 && !repeat) return length;
+		return -1; /* Error, or do not support >16K extensions */
+	}
+}
+
+ssize_t
+aper_get_nsnnwn(asn_per_data_t *pd, int range) {
+	ssize_t value;
+	int bytes = 0;
+
+	ASN_DEBUG("getting nsnnwn with range %d", range);
+
+	if(range <= 255) {
+		int i;
+
+		if (range < 0) return -1;
+		/* 1 -> 8 bits */
+		for (i = 1; i <= 8; i++) {
+			int upper = 1 << i;
+			if (upper >= range)
+				break;
+		}
+		value = per_get_few_bits(pd, i);
+		return value;
+	} else if (range == 256){
+		/* 1 byte */
+		bytes = 1;
+	} else if (range <= 65536) {
+		/* 2 bytes */
+		bytes = 2;
+	} else {
+		return -1;
+	}
+	if (aper_get_align(pd) < 0)
+		return -1;
+	value = per_get_few_bits(pd, 8 * bytes);
+	return value;
+}
+
+int aper_put_align(asn_per_outp_t *po) {
+
+	if(po->nboff & 0x7) {
+		ASN_DEBUG("Aligning %ld bits", 8 - ((unsigned long)po->nboff & 0x7));
+		if(per_put_few_bits(po, 0x00, (8 - (po->nboff & 0x7))))
+			return -1;
+	}
+	return 0;
+}
+
+ssize_t
+aper_put_length(asn_per_outp_t *po, int range, size_t length) {
+
+	ASN_DEBUG("APER put length %zu with range %d", length, range);
+
+	/* 10.9 X.691 Note 2 */
+	if (range <= 65536 && range >= 0)
+		return aper_put_nsnnwn(po, range, length);
+
+	if (aper_put_align(po) < 0)
+		return -1;
+
+	if(length <= 127)	   /* #10.9.3.6 */{
+		return per_put_few_bits(po, length, 8)
+		? -1 : (ssize_t)length;
+	}
+	else if(length < 16384) /* #10.9.3.7 */
+		return per_put_few_bits(po, length|0x8000, 16)
+		? -1 : (ssize_t)length;
+
+	length >>= 14;
+	if(length > 4) length = 4;
+
+	return per_put_few_bits(po, 0xC0 | length, 8)
+	? -1 : (ssize_t)(length << 14);
+}
+
+
+int
+aper_put_nslength(asn_per_outp_t *po, size_t length) {
+
+	if(length <= 64) {
+		/* #10.9.3.4 */
+		if(length == 0) return -1;
+		return per_put_few_bits(po, length-1, 7) ? -1 : 0;
+	} else {
+		if(aper_put_length(po, -1, length) != (ssize_t)length) {
+			/* This might happen in case of >16K extensions */
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+int
+aper_put_nsnnwn(asn_per_outp_t *po, int range, int number) {
+	int bytes;
+
+    ASN_DEBUG("aper put nsnnwn %d with range %d", number, range);
+	/* 10.5.7.1 X.691 */
+	if(range < 0) {
+		int i;
+		for (i = 1; ; i++) {
+			int bits = 1 << (8 * i);
+			if (number <= bits)
+				break;
+		}
+		bytes = i;
+		assert(i <= 4);
+	}
+	if(range <= 255) {
+		int i;
+		for (i = 1; i <= 8; i++) {
+			int bits = 1 << i;
+			if (range <= bits)
+				break;
+		}
+		return per_put_few_bits(po, number, i);
+	} else if(range == 256) {
+		bytes = 1;
+	} else if(range <= 65536) {
+		bytes = 2;
+	} else { /* Ranges > 64K */
+		int i;
+		for (i = 1; ; i++) {
+			int bits = 1 << (8 * i);
+			if (range <= bits)
+				break;
+		}
+		assert(i <= 4);
+		bytes = i;
+	}
+	if(aper_put_align(po) < 0) /* Aligning on octet */
+		return -1;
+/* 	if(per_put_few_bits(po, bytes, 8))
+		return -1;
+*/
+    return per_put_few_bits(po, number, 8 * bytes);
+}