| /*- |
| * Copyright (c) 2003, 2004 Lev Walkin <vlm@lionet.info>. All rights reserved. |
| * Redistribution and modifications are permitted subject to BSD license. |
| */ |
| #include <OBJECT_IDENTIFIER.h> |
| #include <limits.h> /* for CHAR_BIT */ |
| #include <assert.h> |
| #include <errno.h> |
| |
| /* |
| * OBJECT IDENTIFIER basic type description. |
| */ |
| static ber_tlv_tag_t asn1_DEF_OBJECT_IDENTIFIER_tags[] = { |
| (ASN_TAG_CLASS_UNIVERSAL | (6 << 2)) |
| }; |
| asn1_TYPE_descriptor_t asn1_DEF_OBJECT_IDENTIFIER = { |
| "OBJECT IDENTIFIER", |
| OBJECT_IDENTIFIER_constraint, |
| INTEGER_decode_ber, /* Implemented in terms of INTEGER type */ |
| OBJECT_IDENTIFIER_encode_der, |
| OBJECT_IDENTIFIER_print, |
| INTEGER_free, |
| 0, /* Use generic outmost tag fetcher */ |
| asn1_DEF_OBJECT_IDENTIFIER_tags, |
| sizeof(asn1_DEF_OBJECT_IDENTIFIER_tags) |
| / sizeof(asn1_DEF_OBJECT_IDENTIFIER_tags[0]), |
| 1, /* Single UNIVERSAL tag may be implicitly overriden */ |
| 0, /* Always in primitive form */ |
| 0, 0, /* No members */ |
| 0 /* No specifics */ |
| }; |
| |
| |
| /* |
| * Encode OBJECT IDENTIFIER type using DER. |
| */ |
| der_enc_rval_t |
| OBJECT_IDENTIFIER_encode_der(asn1_TYPE_descriptor_t *sd, void *ptr, |
| int tag_mode, ber_tlv_tag_t tag, |
| asn_app_consume_bytes_f *cb, void *app_key) { |
| der_enc_rval_t erval; |
| OBJECT_IDENTIFIER_t *st = (OBJECT_IDENTIFIER_t *)ptr; |
| |
| ASN_DEBUG("%s %s as OBJECT IDENTIFIER (tm=%d)", |
| cb?"Encoding":"Estimating", sd->name, tag_mode); |
| |
| erval.encoded = der_write_tags(sd, st->size, tag_mode, tag, |
| cb, app_key); |
| ASN_DEBUG("OBJECT IDENTIFIER %s wrote tags %d", |
| sd->name, (int)erval.encoded); |
| if(erval.encoded == -1) { |
| erval.failed_type = sd; |
| erval.structure_ptr = ptr; |
| return erval; |
| } |
| |
| if(cb && st->buf) { |
| ssize_t ret; |
| |
| ret = cb(st->buf, st->size, app_key); |
| if(ret == -1) { |
| erval.encoded = -1; |
| erval.failed_type = sd; |
| erval.structure_ptr = ptr; |
| return erval; |
| } |
| } else { |
| assert(st->buf || st->size == 0); |
| } |
| |
| erval.encoded += st->size; |
| |
| return erval; |
| } |
| |
| int |
| OBJECT_IDENTIFIER_constraint(asn1_TYPE_descriptor_t *td, const void *sptr, |
| asn_app_consume_bytes_f *app_errlog, void *app_key) { |
| const OBJECT_IDENTIFIER_t *st = (const OBJECT_IDENTIFIER_t *)sptr; |
| |
| if(st && st->buf) { |
| if(st->size < 1) { |
| _ASN_ERRLOG(app_errlog, app_key, |
| "%s: at least one numerical value " |
| "expected (%s:%d)", |
| td->name, __FILE__, __LINE__); |
| return -1; |
| } |
| } else { |
| _ASN_ERRLOG(app_errlog, app_key, |
| "%s: value not given (%s:%d)", |
| td->name, __FILE__, __LINE__); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| |
| int |
| OBJECT_IDENTIFIER_get_single_arc(uint8_t *arcbuf, unsigned int arclen, signed int add, void *rvbuf, unsigned int rvsize) { |
| unsigned LE = 1; /* Little endian (x86) */ |
| uint8_t *arcend = arcbuf + arclen; /* End of arc */ |
| void *rvstart = rvbuf; /* Original start of the value buffer */ |
| unsigned int cache = 0; /* No more than 14 significant bits */ |
| int inc; /* Return value growth direction */ |
| |
| rvsize *= CHAR_BIT; /* bytes to bits */ |
| arclen *= 7; /* bytes to bits */ |
| |
| /* |
| * The arc has the number of bits |
| * cannot be represented using supplied return value type. |
| */ |
| if(arclen > rvsize) { |
| if(arclen > (rvsize + CHAR_BIT)) { |
| errno = ERANGE; /* Overflow */ |
| return -1; |
| } else { |
| /* |
| * Even if the number of bits in the arc representation |
| * is higher than the width of supplied * return value |
| * type, there is still possible to fit it when there |
| * are few unused high bits in the arc value |
| * representaion. |
| * |
| * Moreover, there is a possibility that the |
| * number could actually fit the arc space, given |
| * that add is negative, but we don't handle |
| * such "temporary lack of precision" situation here. |
| * May be considered as a bug. |
| */ |
| uint8_t mask = (0xff << (7-(arclen - rvsize))) & 0x7f; |
| if((*arcbuf & mask)) { |
| errno = ERANGE; /* Overflow */ |
| return -1; |
| } |
| /* Fool the routine computing unused bits */ |
| arclen -= 7; |
| cache = *arcbuf & 0x7f; |
| arcbuf++; |
| } |
| } |
| |
| /* Faster path for common size */ |
| if(rvsize == (CHAR_BIT * sizeof(unsigned long))) { |
| unsigned long accum; |
| /* Gather all bits into the accumulator */ |
| for(accum = cache; arcbuf < arcend; arcbuf++) |
| accum = (accum << 7) | (*arcbuf & ~0x80); |
| if(accum < (unsigned)-add) { |
| errno = ERANGE; /* Overflow */ |
| return -1; |
| } |
| *(unsigned long *)rvbuf = accum + add; |
| return 0; |
| } |
| |
| #ifndef WORDS_BIGENDIAN |
| if(*(unsigned char *)&LE) { /* Little endian (x86) */ |
| /* "Convert" to big endian */ |
| (unsigned char *)rvbuf += rvsize / CHAR_BIT - 1; |
| ((unsigned char *)rvstart)--; |
| inc = -1; /* Descending */ |
| } else |
| #endif /* !WORDS_BIGENDIAN */ |
| inc = +1; /* Big endian is known [at compile time] */ |
| |
| { |
| int bits; /* typically no more than 3-4 bits */ |
| |
| /* Clear the high unused bits */ |
| for(bits = rvsize - arclen; |
| bits > CHAR_BIT; |
| (unsigned char *)rvbuf += inc, bits -= CHAR_BIT) |
| *(unsigned char *)rvbuf = 0; |
| |
| /* Fill the body of a value */ |
| for(; arcbuf < arcend; arcbuf++) { |
| cache = (cache << 7) | (*arcbuf & 0x7f); |
| bits += 7; |
| if(bits >= CHAR_BIT) { |
| bits -= CHAR_BIT; |
| *(unsigned char *)rvbuf = (cache >> bits); |
| (unsigned char *)rvbuf += inc; |
| } |
| } |
| if(bits) { |
| *(unsigned char *)rvbuf = cache; |
| (unsigned char *)rvbuf += inc; |
| } |
| } |
| |
| if(add) { |
| for((unsigned char *)rvbuf -= inc; rvbuf != rvstart; (unsigned char *)rvbuf -= inc) { |
| int v = add + *(unsigned char *)rvbuf; |
| if(v & (-1 << CHAR_BIT)) { |
| *(unsigned char *)rvbuf |
| = (unsigned char)(v + (1 << CHAR_BIT)); |
| add = -1; |
| } else { |
| *(unsigned char *)rvbuf = v; |
| break; |
| } |
| } |
| if(rvbuf == rvstart) { |
| /* No space to carry over */ |
| errno = ERANGE; /* Overflow */ |
| return -1; |
| } |
| } |
| |
| return 0; |
| } |
| |
| |
| int |
| OBJECT_IDENTIFIER_print_arc(uint8_t *arcbuf, int arclen, int add, |
| asn_app_consume_bytes_f *cb, void *app_key) { |
| char scratch[64]; /* Conservative estimate */ |
| unsigned long accum; /* Bits accumulator */ |
| char *p; /* Position in the scratch buffer */ |
| |
| if(OBJECT_IDENTIFIER_get_single_arc(arcbuf, arclen, add, |
| &accum, sizeof(accum))) |
| return -1; |
| |
| if(accum) { |
| /* Fill the scratch buffer in reverse. */ |
| p = scratch + sizeof(scratch); |
| for(; accum; accum /= 10) |
| *(--p) = (char)(accum % 10) + 0x30; |
| |
| return cb(p, sizeof(scratch) - (p - scratch), app_key); |
| } else { |
| *scratch = 0x30; |
| return cb(scratch, 1, app_key); |
| } |
| } |
| |
| int |
| OBJECT_IDENTIFIER_print(asn1_TYPE_descriptor_t *td, const void *sptr, |
| int ilevel, asn_app_consume_bytes_f *cb, void *app_key) { |
| const OBJECT_IDENTIFIER_t *st = (const OBJECT_IDENTIFIER_t *)sptr; |
| int startn; |
| int add = 0; |
| int i; |
| |
| (void)td; /* Unused argument */ |
| (void)ilevel; /* Unused argument */ |
| |
| if(!st || !st->buf) |
| return cb("<absent>", 8, app_key); |
| |
| /* Dump preamble */ |
| if(cb("{ ", 2, app_key)) |
| return -1; |
| |
| for(i = 0, startn = 0; i < st->size; i++) { |
| uint8_t b = st->buf[i]; |
| if((b & 0x80)) /* Continuation expected */ |
| continue; |
| |
| if(startn == 0) { |
| /* |
| * First two arcs are encoded through the backdoor. |
| */ |
| if(i) { |
| add = -80; |
| if(cb("2", 1, app_key)) return -1; |
| } else if(b <= 39) { |
| add = 0; |
| if(cb("0", 1, app_key)) return -1; |
| } else if(b < 79) { |
| add = -40; |
| if(cb("1", 1, app_key)) return -1; |
| } else { |
| add = -80; |
| if(cb("2", 1, app_key)) return -1; |
| } |
| } |
| |
| if(cb(" ", 1, app_key)) /* Separate arcs */ |
| return -1; |
| |
| if(OBJECT_IDENTIFIER_print_arc(&st->buf[startn], |
| i - startn + 1, add, |
| cb, app_key)) |
| return -1; |
| startn = i + 1; |
| add = 0; |
| } |
| |
| return cb(" }", 2, app_key); |
| } |
| |
| int |
| OBJECT_IDENTIFIER_get_arcs(OBJECT_IDENTIFIER_t *oid, void *arcs, |
| unsigned int arc_type_size, unsigned int arc_slots) { |
| void *arcs_end = (char *)arcs + (arc_type_size * arc_slots); |
| int num_arcs = 0; |
| int startn = 0; |
| int add = 0; |
| int i; |
| |
| if(!oid || !oid->buf || (arc_slots && arc_type_size <= 1)) { |
| errno = EINVAL; |
| return -1; |
| } |
| |
| for(i = 0; i < oid->size; i++) { |
| uint8_t b = oid->buf[i]; |
| if((b & 0x80)) /* Continuation expected */ |
| continue; |
| |
| if(num_arcs == 0) { |
| /* |
| * First two arcs are encoded through the backdoor. |
| */ |
| unsigned LE = 1; /* Little endian */ |
| int first_arc; |
| num_arcs++; |
| if(!arc_slots) { num_arcs++; continue; } |
| |
| if(i) first_arc = 2; |
| else if(b <= 39) first_arc = 0; |
| else if(b < 79) first_arc = 1; |
| else first_arc = 2; |
| |
| add = -40 * first_arc; |
| memset(arcs, 0, arc_type_size); |
| *(unsigned char *)((char *)arcs |
| + ((*(char *)&LE)?0:(arc_type_size - 1))) |
| = first_arc; |
| (char *)arcs += arc_type_size; |
| } |
| |
| /* Decode, if has space */ |
| if(arcs < arcs_end) { |
| if(OBJECT_IDENTIFIER_get_single_arc(&oid->buf[startn], |
| i - startn + 1, add, |
| arcs, arc_type_size)) |
| return -1; |
| startn = i + 1; |
| (char *)arcs += arc_type_size; |
| add = 0; |
| } |
| num_arcs++; |
| } |
| |
| return num_arcs; |
| } |
| |
| |
| /* |
| * Save the single value as an object identifier arc. |
| */ |
| int |
| OBJECT_IDENTIFIER_set_single_arc(uint8_t *arcbuf, void *arcval, unsigned int arcval_size, int prepared_order) { |
| /* |
| * The following conditions must hold: |
| * assert(arcval); |
| * assert(arcval_size > 0); |
| * assert(arcbuf); |
| */ |
| #ifdef WORDS_BIGENDIAN |
| const unsigned isLittleEndian = 0; |
| #else |
| unsigned LE = 1; |
| unsigned isLittleEndian = *(char *)&LE; |
| #endif |
| uint8_t *tp, *tend; |
| unsigned int cache; |
| uint8_t *bp = arcbuf; |
| int bits; |
| #ifdef __GNUC__ |
| uint8_t buffer[arcval_size]; |
| #else |
| uint8_t *buffer = alloca(arcval_size); |
| if(!buffer) { errno = ENOMEM; return -1; } |
| #endif |
| |
| if(isLittleEndian && !prepared_order) { |
| uint8_t *a = (unsigned char *)arcval + arcval_size - 1; |
| uint8_t *aend = (uint8_t *)arcval; |
| uint8_t *msb = buffer + arcval_size - 1; |
| for(tp = buffer; a >= aend; tp++, a--) |
| if((*tp = *a) && (tp < msb)) |
| msb = tp; |
| tend = &buffer[arcval_size]; |
| tp = msb; /* Most significant non-zero byte */ |
| } else { |
| /* Look for most significant non-zero byte */ |
| tend = (unsigned char *)arcval + arcval_size; |
| for(tp = (uint8_t *)arcval; tp < tend - 1; tp++) |
| if(*tp) break; |
| } |
| |
| /* |
| * Split the value in 7-bits chunks. |
| */ |
| bits = ((tend - tp) * CHAR_BIT) % 7; |
| if(bits) { |
| cache = *tp >> (CHAR_BIT - bits); |
| if(cache) { |
| *bp++ = cache | 0x80; |
| cache = *tp++; |
| bits = CHAR_BIT - bits; |
| } else { |
| bits = -bits; |
| } |
| } else { |
| cache = 0; |
| } |
| for(; tp < tend; tp++) { |
| cache = (cache << CHAR_BIT) + *tp; |
| bits += CHAR_BIT; |
| while(bits >= 7) { |
| bits -= 7; |
| *bp++ = 0x80 | (cache >> bits); |
| } |
| } |
| if(bits) *bp++ = cache; |
| bp[-1] &= 0x7f; /* Clear the last bit */ |
| |
| return bp - arcbuf; |
| } |
| |
| int |
| OBJECT_IDENTIFIER_set_arcs(OBJECT_IDENTIFIER_t *oid, void *arcs, unsigned int arc_type_size, unsigned int arc_slots) { |
| uint8_t *buf; |
| uint8_t *bp; |
| unsigned LE = 1; /* Little endian (x86) */ |
| unsigned isLittleEndian = *((char *)&LE); |
| unsigned int arc0; |
| unsigned int arc1; |
| unsigned size; |
| unsigned i; |
| |
| if(!oid || !arcs || arc_type_size < 1 || arc_slots < 2) { |
| errno = EINVAL; |
| return -1; |
| } |
| |
| switch(arc_type_size) { |
| case sizeof(char): |
| arc0 = ((unsigned char *)arcs)[0]; |
| arc1 = ((unsigned char *)arcs)[1]; |
| break; |
| case sizeof(short): |
| arc0 = ((unsigned short *)arcs)[0]; |
| arc1 = ((unsigned short *)arcs)[1]; |
| break; |
| case sizeof(int): |
| arc0 = ((unsigned int *)arcs)[0]; |
| arc1 = ((unsigned int *)arcs)[1]; |
| break; |
| default: |
| arc1 = arc0 = 0; |
| if(isLittleEndian) { /* Little endian (x86) */ |
| unsigned char *ps, *pe; |
| /* If more significant bytes are present, |
| * make them > 255 quick */ |
| for(ps = (unsigned char *)arcs + 1, pe = ps+arc_type_size; |
| ps < pe; ps++) |
| arc0 |= *ps, arc1 |= *(ps + arc_type_size); |
| arc0 <<= CHAR_BIT, arc1 <<= CHAR_BIT; |
| arc0 = *((unsigned char *)arcs + 0); |
| arc1 = *((unsigned char *)arcs + arc_type_size); |
| } else { |
| unsigned char *ps, *pe; |
| /* If more significant bytes are present, |
| * make them > 255 quick */ |
| for(ps = (unsigned char *)arcs, pe = ps+arc_type_size - 1; ps < pe; ps++) |
| arc0 |= *ps, arc1 |= *(ps + arc_type_size); |
| arc0 = *((unsigned char *)arcs + arc_type_size - 1); |
| arc1 = *((unsigned char *)arcs +(arc_type_size<< 1)-1); |
| } |
| } |
| |
| /* |
| * The previous chapter left us with the first and the second arcs. |
| * The values are not precise (that is, they are valid only if |
| * they're less than 255), but OK for the purposes of making |
| * the sanity test below. |
| */ |
| if(arc0 <= 1) { |
| if(arc1 >= 39) { |
| /* 8.19.4: At most 39 subsequent values (including 0) */ |
| errno = ERANGE; |
| return -1; |
| } |
| } else if(arc0 > 2) { |
| /* 8.19.4: Only three values are allocated from the root node */ |
| errno = ERANGE; |
| return -1; |
| } |
| /* |
| * After above tests it is known that the value of arc0 is completely |
| * trustworthy (0..2). However, the arc1's value is still meaningless. |
| */ |
| |
| /* |
| * Roughly estimate the maximum size necessary to encode these arcs. |
| * This estimation implicitly takes in account the following facts, |
| * that cancel each other: |
| * * the first two arcs are encoded in a single value. |
| * * the first value may require more space (+1 byte) |
| * * the value of the first arc which is in range (0..2) |
| */ |
| size = ((arc_type_size * CHAR_BIT + 6) / 7) * arc_slots; |
| bp = buf = (uint8_t *)MALLOC(size + 1); |
| if(!buf) { |
| /* ENOMEM */ |
| return -1; |
| } |
| |
| /* |
| * Encode the first two arcs. |
| * These require special treatment. |
| */ |
| { |
| uint8_t *tp; |
| #ifdef __GNUC__ |
| uint8_t first_value[1 + arc_type_size]; /* of two arcs */ |
| uint8_t *fv = first_value; |
| #else |
| uint8_t *first_value = alloca(1 + arc_type_size); |
| uint8_t *fv = first_value; |
| if(!first_value) { |
| errno = ENOMEM; |
| return -1; |
| } |
| #endif |
| |
| /* |
| * Simulate first_value = arc0 * 40 + arc1; |
| */ |
| /* Copy the second (1'st) arcs[1] into the first_value */ |
| *fv++ = 0; |
| (char *)arcs += arc_type_size; |
| if(isLittleEndian) { |
| uint8_t *aend = (unsigned char *)arcs - 1; |
| uint8_t *a1 = (unsigned char *)arcs + arc_type_size - 1; |
| for(; a1 > aend; fv++, a1--) *fv = *a1; |
| } else { |
| uint8_t *a1 = (uint8_t *)arcs; |
| uint8_t *aend = a1 + arc_type_size; |
| for(; a1 < aend; fv++, a1++) *fv = *a1; |
| } |
| /* Increase the first_value by arc0 */ |
| arc0 *= 40; /* (0..80) */ |
| for(tp = first_value + arc_type_size; tp >= first_value; tp--) { |
| unsigned int v = *tp; |
| v += arc0; |
| *tp = v; |
| if(v >= (1 << CHAR_BIT)) arc0 = v >> CHAR_BIT; |
| else break; |
| } |
| |
| assert(tp >= first_value); |
| |
| bp += OBJECT_IDENTIFIER_set_single_arc(bp, first_value, |
| fv - first_value, 1); |
| } |
| |
| /* |
| * Save the rest of arcs. |
| */ |
| for((char *)arcs += arc_type_size, i = 2; |
| i < arc_slots; i++, (char *)arcs += arc_type_size) { |
| bp += OBJECT_IDENTIFIER_set_single_arc(bp, |
| arcs, arc_type_size, 0); |
| } |
| |
| assert((unsigned)(bp - buf) <= size); |
| |
| /* |
| * Replace buffer. |
| */ |
| oid->size = bp - buf; |
| bp = oid->buf; |
| oid->buf = buf; |
| if(bp) FREEMEM(bp); |
| |
| return 0; |
| } |
| |