/*- * Copyright (c) 2003 Lev Walkin . All rights reserved. * Redistribution and modifications are permitted subject to BSD license. */ #include #include #include /* Encoder and decoder of a primitive */ #include #include /* * 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", 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("", 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; }