| /*- |
| * Copyright (c) 2003 Lev Walkin <vlm@lionet.info>. All rights reserved. |
| * Redistribution and modifications are permitted subject to BSD license. |
| */ |
| #include <asn_internal.h> |
| #include <INTEGER.h> |
| #include <ber_codec_prim.h> /* Encoder and decoder of a primitive */ |
| #include <assert.h> |
| #include <errno.h> |
| |
| /* |
| * INTEGER basic type description. |
| */ |
| static ber_tlv_tag_t asn_DEF_INTEGER_tags[] = { |
| (ASN_TAG_CLASS_UNIVERSAL | (2 << 2)) |
| }; |
| asn_TYPE_descriptor_t asn_DEF_INTEGER = { |
| "INTEGER", |
| "INTEGER", |
| ASN__PRIMITIVE_TYPE_free, |
| INTEGER_print, |
| asn_generic_no_constraint, |
| ber_decode_primitive, |
| INTEGER_encode_der, |
| 0, /* Not implemented yet */ |
| INTEGER_encode_xer, |
| 0, /* Use generic outmost tag fetcher */ |
| asn_DEF_INTEGER_tags, |
| sizeof(asn_DEF_INTEGER_tags) / sizeof(asn_DEF_INTEGER_tags[0]), |
| asn_DEF_INTEGER_tags, /* Same as above */ |
| sizeof(asn_DEF_INTEGER_tags) / sizeof(asn_DEF_INTEGER_tags[0]), |
| 0, 0, /* No members */ |
| 0 /* No specifics */ |
| }; |
| |
| /* |
| * Encode INTEGER type using DER. |
| */ |
| asn_enc_rval_t |
| INTEGER_encode_der(asn_TYPE_descriptor_t *td, void *sptr, |
| int tag_mode, ber_tlv_tag_t tag, |
| asn_app_consume_bytes_f *cb, void *app_key) { |
| INTEGER_t *st = (INTEGER_t *)sptr; |
| |
| ASN_DEBUG("%s %s as INTEGER (tm=%d)", |
| cb?"Encoding":"Estimating", td->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) */ |
| |
| return der_encode_primitive(td, sptr, tag_mode, tag, cb, app_key); |
| } |
| |
| /* |
| * INTEGER specific human-readable output. |
| */ |
| static ssize_t |
| INTEGER__dump(const INTEGER_t *st, asn_app_consume_bytes_f *cb, void *app_key) { |
| char scratch[32]; /* Enough for 64-bit integer */ |
| uint8_t *buf = st->buf; |
| uint8_t *buf_end = st->buf + st->size; |
| signed long accum; |
| ssize_t wrote = 0; |
| char *p; |
| int ret; |
| |
| if(st->size == 0) { |
| return (cb("0", 1, app_key) < 0) ? -1 : 1; |
| } |
| |
| /* |
| * Advance buf pointer until the start of the value's body. |
| * This will make us able to process large integers using simple case, |
| * when the actual value is small |
| * (0x0000000000abcdef would yield a fine 0x00abcdef) |
| */ |
| /* Skip the insignificant leading bytes */ |
| for(; buf < buf_end-1; buf++) { |
| switch(*buf) { |
| case 0x00: if((buf[1] & 0x80) == 0) continue; break; |
| case 0xff: if((buf[1] & 0x80) != 0) continue; break; |
| } |
| break; |
| } |
| |
| /* Simple case: the integer size is small */ |
| if((size_t)(buf_end - buf) <= sizeof(accum)) { |
| accum = (*buf & 0x80) ? -1 : 0; |
| for(; buf < buf_end; buf++) |
| accum = (accum << 8) | *buf; |
| ret = snprintf(scratch, sizeof(scratch), "%ld", accum); |
| assert(ret > 0 && ret < (int)sizeof(scratch)); |
| return (cb(scratch, ret, app_key) < 0) ? -1 : ret; |
| } |
| |
| /* Output in the long xx:yy:zz... format */ |
| /* TODO: replace with generic algorithm (Knuth TAOCP Vol 2, 4.3.1) */ |
| for(p = scratch; buf < buf_end; buf++) { |
| static const char *h2c = "0123456789ABCDEF"; |
| if((p - scratch) >= (ssize_t)(sizeof(scratch) - 4)) { |
| /* Flush buffer */ |
| if(cb(scratch, p - scratch, app_key) < 0) |
| return -1; |
| wrote += p - scratch; |
| p = scratch; |
| } |
| *p++ = h2c[*buf >> 4]; |
| *p++ = h2c[*buf & 0x0F]; |
| *p++ = 0x3a; /* ":" */ |
| } |
| if(p != scratch) |
| p--; /* Remove the last ":" */ |
| |
| wrote += p - scratch; |
| return (cb(scratch, p - scratch, app_key) < 0) ? -1 : wrote; |
| } |
| |
| /* |
| * INTEGER specific human-readable output. |
| */ |
| int |
| INTEGER_print(asn_TYPE_descriptor_t *td, const void *sptr, int ilevel, |
| asn_app_consume_bytes_f *cb, void *app_key) { |
| const INTEGER_t *st = (const INTEGER_t *)sptr; |
| ssize_t ret; |
| |
| (void)td; |
| (void)ilevel; |
| |
| if(!st && !st->buf) |
| ret = cb("<absent>", 8, app_key); |
| else |
| ret = INTEGER__dump(st, cb, app_key); |
| |
| return (ret < 0) ? -1 : 0; |
| } |
| |
| asn_enc_rval_t |
| INTEGER_encode_xer(asn_TYPE_descriptor_t *td, void *sptr, |
| int ilevel, enum xer_encoder_flags_e flags, |
| asn_app_consume_bytes_f *cb, void *app_key) { |
| const INTEGER_t *st = (const INTEGER_t *)sptr; |
| asn_enc_rval_t er; |
| |
| (void)ilevel; |
| (void)flags; |
| |
| if(!st && !st->buf) |
| _ASN_ENCODE_FAILED; |
| |
| er.encoded = INTEGER__dump(st, cb, app_key); |
| if(er.encoded < 0) _ASN_ENCODE_FAILED; |
| |
| return er; |
| } |
| |
| int |
| asn_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; |
| } |