| /* |
| * Copyright (c) 2005-2014 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> |
| |
| char * |
| per_data_string(asn_per_data_t *pd) { |
| static char buf[2][32]; |
| static int n; |
| n = (n+1) % 2; |
| snprintf(buf[n], sizeof(buf[n]), |
| "{m=%ld span %+ld[%d..%d] (%d)}", |
| (long)pd->moved, |
| (((long)pd->buffer) & 0xf), |
| (int)pd->nboff, (int)pd->nbits, |
| (int)(pd->nbits - pd->nboff)); |
| return buf[n]; |
| } |
| |
| void |
| per_get_undo(asn_per_data_t *pd, int nbits) { |
| if((ssize_t)pd->nboff < nbits) { |
| assert((ssize_t)pd->nboff < nbits); |
| } else { |
| pd->nboff -= nbits; |
| pd->moved -= nbits; |
| } |
| } |
| |
| /* |
| * Extract a small number of bits (<= 31) from the specified PER data pointer. |
| */ |
| int32_t |
| per_get_few_bits(asn_per_data_t *pd, int nbits) { |
| size_t off; /* Next after last bit offset */ |
| ssize_t nleft; /* Number of bits left in this stream */ |
| uint32_t accum; |
| const uint8_t *buf; |
| |
| if(nbits < 0) |
| return -1; |
| |
| nleft = pd->nbits - pd->nboff; |
| if(nbits > nleft) { |
| int32_t tailv, vhead; |
| if(!pd->refill || nbits > 31) return -1; |
| /* Accumulate unused bytes before refill */ |
| ASN_DEBUG("Obtain the rest %d bits (want %d)", |
| (int)nleft, (int)nbits); |
| tailv = per_get_few_bits(pd, nleft); |
| if(tailv < 0) return -1; |
| /* Refill (replace pd contents with new data) */ |
| if(pd->refill(pd)) |
| return -1; |
| nbits -= nleft; |
| vhead = per_get_few_bits(pd, nbits); |
| /* Combine the rest of previous pd with the head of new one */ |
| tailv = (tailv << nbits) | vhead; /* Could == -1 */ |
| return tailv; |
| } |
| |
| /* |
| * Normalize position indicator. |
| */ |
| if(pd->nboff >= 8) { |
| pd->buffer += (pd->nboff >> 3); |
| pd->nbits -= (pd->nboff & ~0x07); |
| pd->nboff &= 0x07; |
| } |
| pd->moved += nbits; |
| pd->nboff += nbits; |
| off = pd->nboff; |
| buf = pd->buffer; |
| |
| /* |
| * Extract specified number of bits. |
| */ |
| if(off <= 8) |
| accum = nbits ? (buf[0]) >> (8 - off) : 0; |
| else if(off <= 16) |
| accum = ((buf[0] << 8) + buf[1]) >> (16 - off); |
| else if(off <= 24) |
| accum = ((buf[0] << 16) + (buf[1] << 8) + buf[2]) >> (24 - off); |
| else if(off <= 31) |
| accum = ((buf[0] << 24) + (buf[1] << 16) |
| + (buf[2] << 8) + (buf[3])) >> (32 - off); |
| else if(nbits <= 31) { |
| asn_per_data_t tpd = *pd; |
| /* Here are we with our 31-bits limit plus 1..7 bits offset. */ |
| per_get_undo(&tpd, nbits); |
| /* The number of available bits in the stream allow |
| * for the following operations to take place without |
| * invoking the ->refill() function */ |
| accum = per_get_few_bits(&tpd, nbits - 24) << 24; |
| accum |= per_get_few_bits(&tpd, 24); |
| } else { |
| per_get_undo(pd, nbits); |
| return -1; |
| } |
| |
| accum &= (((uint32_t)1 << nbits) - 1); |
| |
| ASN_DEBUG(" [PER got %2d<=%2d bits => span %d %+ld[%d..%d]:%02x (%d) => 0x%x]", |
| (int)nbits, (int)nleft, |
| (int)pd->moved, |
| (((long)pd->buffer) & 0xf), |
| (int)pd->nboff, (int)pd->nbits, |
| ((pd->buffer != NULL)?pd->buffer[0]:0), |
| (int)(pd->nbits - pd->nboff), |
| (int)accum); |
| |
| return accum; |
| } |
| |
| /* |
| * Extract a large number of bits from the specified PER data pointer. |
| */ |
| int |
| per_get_many_bits(asn_per_data_t *pd, uint8_t *dst, int alright, int nbits) { |
| int32_t value; |
| |
| if(alright && (nbits & 7)) { |
| /* Perform right alignment of a first few bits */ |
| value = per_get_few_bits(pd, nbits & 0x07); |
| if(value < 0) return -1; |
| *dst++ = value; /* value is already right-aligned */ |
| nbits &= ~7; |
| } |
| |
| while(nbits) { |
| if(nbits >= 24) { |
| value = per_get_few_bits(pd, 24); |
| if(value < 0) return -1; |
| *(dst++) = value >> 16; |
| *(dst++) = value >> 8; |
| *(dst++) = value; |
| nbits -= 24; |
| } else { |
| value = per_get_few_bits(pd, nbits); |
| if(value < 0) return -1; |
| if(nbits & 7) { /* implies left alignment */ |
| value <<= 8 - (nbits & 7), |
| nbits += 8 - (nbits & 7); |
| if(nbits > 24) |
| *dst++ = value >> 24; |
| } |
| if(nbits > 16) |
| *dst++ = value >> 16; |
| if(nbits > 8) |
| *dst++ = value >> 8; |
| *dst++ = value; |
| break; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * 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, int *repeat) { |
| ssize_t value; |
| |
| *repeat = 0; |
| |
| /* #11.9.4.1 Encoding if constrained (according to effective bits) */ |
| if(ebits >= 0 && ebits <= 16) { |
| return per_get_few_bits(pd, ebits); |
| } |
| |
| 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) { |
| 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, &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_s(asn_per_outp_t *po, long v, int nbits) { |
| /* |
| * Assume signed number can be safely coerced into |
| * unsigned of the same range. |
| * The following testing code will likely be optimized out |
| * by compiler if it is true. |
| */ |
| unsigned long uvalue1 = ULONG_MAX; |
| long svalue = uvalue1; |
| unsigned long uvalue2 = svalue; |
| assert(uvalue1 == uvalue2); |
| return uper_put_constrained_whole_number_u(po, v, nbits); |
| } |
| |
| 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); |
| } |
| } |
| |
| int |
| per_put_aligned_flush(asn_per_outp_t *po) { |
| uint32_t unused_bits = (0x7 & (8 - (po->nboff & 0x07))); |
| size_t complete_bytes = |
| (po->buffer ? po->buffer - po->tmpspace : 0) + ((po->nboff + 7) >> 3); |
| |
| if(unused_bits) { |
| po->buffer[po->nboff >> 3] &= ~0 << unused_bits; |
| } |
| |
| if(po->outper(po->tmpspace, complete_bytes, po->op_key) < 0) { |
| return -1; |
| } else { |
| po->buffer = po->tmpspace; |
| po->nboff = 0; |
| po->nbits = 8 * sizeof(po->tmpspace); |
| po->flushed_bytes += complete_bytes; |
| return 0; |
| } |
| } |
| |
| /* |
| * Put a small number of bits (<= 31). |
| */ |
| int |
| per_put_few_bits(asn_per_outp_t *po, uint32_t bits, int obits) { |
| size_t off; /* Next after last bit offset */ |
| size_t omsk; /* Existing last byte meaningful bits mask */ |
| uint8_t *buf; |
| |
| if(obits <= 0 || obits >= 32) return obits ? -1 : 0; |
| |
| ASN_DEBUG("[PER put %d bits %x to %p+%d bits]", |
| obits, (int)bits, po->buffer, (int)po->nboff); |
| |
| /* |
| * Normalize position indicator. |
| */ |
| if(po->nboff >= 8) { |
| po->buffer += (po->nboff >> 3); |
| po->nbits -= (po->nboff & ~0x07); |
| po->nboff &= 0x07; |
| } |
| |
| /* |
| * Flush whole-bytes output, if necessary. |
| */ |
| if(po->nboff + obits > po->nbits) { |
| size_t complete_bytes; |
| if(!po->buffer) po->buffer = po->tmpspace; |
| complete_bytes = (po->buffer - po->tmpspace); |
| ASN_DEBUG("[PER output %ld complete + %ld]", |
| (long)complete_bytes, (long)po->flushed_bytes); |
| if(po->outper(po->tmpspace, complete_bytes, po->op_key) < 0) |
| return -1; |
| if(po->nboff) |
| po->tmpspace[0] = po->buffer[0]; |
| po->buffer = po->tmpspace; |
| po->nbits = 8 * sizeof(po->tmpspace); |
| po->flushed_bytes += complete_bytes; |
| } |
| |
| /* |
| * Now, due to sizeof(tmpspace), we are guaranteed large enough space. |
| */ |
| buf = po->buffer; |
| omsk = ~((1 << (8 - po->nboff)) - 1); |
| off = (po->nboff + obits); |
| |
| /* Clear data of debris before meaningful bits */ |
| bits &= (((uint32_t)1 << obits) - 1); |
| |
| ASN_DEBUG("[PER out %d %u/%x (t=%d,o=%d) %x&%x=%x]", obits, |
| (int)bits, (int)bits, |
| (int)po->nboff, (int)off, |
| buf[0], (int)(omsk&0xff), |
| (int)(buf[0] & omsk)); |
| |
| if(off <= 8) /* Completely within 1 byte */ |
| po->nboff = off, |
| bits <<= (8 - off), |
| buf[0] = (buf[0] & omsk) | bits; |
| else if(off <= 16) |
| po->nboff = off, |
| bits <<= (16 - off), |
| buf[0] = (buf[0] & omsk) | (bits >> 8), |
| buf[1] = bits; |
| else if(off <= 24) |
| po->nboff = off, |
| bits <<= (24 - off), |
| buf[0] = (buf[0] & omsk) | (bits >> 16), |
| buf[1] = bits >> 8, |
| buf[2] = bits; |
| else if(off <= 31) |
| po->nboff = off, |
| bits <<= (32 - off), |
| buf[0] = (buf[0] & omsk) | (bits >> 24), |
| buf[1] = bits >> 16, |
| buf[2] = bits >> 8, |
| buf[3] = bits; |
| else { |
| if(per_put_few_bits(po, bits >> (obits - 24), 24)) return -1; |
| if(per_put_few_bits(po, bits, obits - 24)) return -1; |
| } |
| |
| ASN_DEBUG("[PER out %u/%x => %02x buf+%ld]", |
| (int)bits, (int)bits, buf[0], |
| (long)(po->buffer - po->tmpspace)); |
| |
| return 0; |
| } |
| |
| |
| /* |
| * Output a large number of bits. |
| */ |
| int |
| per_put_many_bits(asn_per_outp_t *po, const uint8_t *src, int nbits) { |
| |
| while(nbits) { |
| uint32_t value; |
| |
| if(nbits >= 24) { |
| value = (src[0] << 16) | (src[1] << 8) | src[2]; |
| src += 3; |
| nbits -= 24; |
| if(per_put_few_bits(po, value, 24)) |
| return -1; |
| } else { |
| value = src[0]; |
| if(nbits > 8) |
| value = (value << 8) | src[1]; |
| if(nbits > 16) |
| value = (value << 8) | src[2]; |
| if(nbits & 0x07) |
| value >>= (8 - (nbits & 0x07)); |
| if(per_put_few_bits(po, value, nbits)) |
| return -1; |
| break; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Put the length "n" (or part of it) into the stream. |
| */ |
| ssize_t |
| uper_put_length(asn_per_outp_t *po, size_t length) { |
| |
| 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); |
| } |
| |
| |
| /* |
| * 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) { |
| /* #10.9.3.4 */ |
| 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; |
| } |
| |