| /*- |
| * Copyright (c) 2004 Lev Walkin <vlm@lionet.info>. All rights reserved. |
| * Redistribution and modifications are permitted subject to BSD license. |
| */ |
| /* |
| * Please read the NativeInteger.h for the explanation wrt. differences between |
| * INTEGER and NativeInteger. |
| * Basically, both are decoders and encoders of ASN.1 INTEGER type, but this |
| * implementation deals with the standard (machine-specific) representation |
| * of them instead of using the platform-independent buffer. |
| */ |
| #include <NativeInteger.h> |
| #include <INTEGER.h> |
| #include <assert.h> |
| |
| /* |
| * NativeInteger basic type description. |
| */ |
| static ber_tlv_tag_t asn1_DEF_NativeInteger_tags[] = { |
| (ASN_TAG_CLASS_UNIVERSAL | (2 << 2)) |
| }; |
| asn1_TYPE_descriptor_t asn1_DEF_NativeInteger = { |
| "INTEGER", /* The ASN.1 type is still INTEGER */ |
| asn_generic_no_constraint, |
| NativeInteger_decode_ber, |
| NativeInteger_encode_der, |
| NativeInteger_print, |
| NativeInteger_free, |
| 0, /* Use generic outmost tag fetcher */ |
| asn1_DEF_NativeInteger_tags, |
| sizeof(asn1_DEF_NativeInteger_tags)/sizeof(asn1_DEF_NativeInteger_tags[0]), |
| 1, /* Single UNIVERSAL tag may be implicitly overriden */ |
| 0, /* Always in primitive form */ |
| 0, 0, /* No members */ |
| 0 /* No specifics */ |
| }; |
| |
| /* |
| * Decode INTEGER type. |
| */ |
| ber_dec_rval_t |
| NativeInteger_decode_ber(asn1_TYPE_descriptor_t *td, |
| void **int_ptr, void *buf_ptr, size_t size, int tag_mode) { |
| int *Int = (int *)*int_ptr; |
| ber_dec_rval_t rval; |
| ber_dec_ctx_t ctx = { 0, 0, 0, 0 }; |
| ber_tlv_len_t length; |
| |
| /* |
| * If the structure is not there, allocate it. |
| */ |
| if(Int == NULL) { |
| (void *)Int = *int_ptr = CALLOC(1, sizeof(*Int)); |
| if(Int == NULL) { |
| rval.code = RC_FAIL; |
| rval.consumed = 0; |
| return rval; |
| } |
| } |
| |
| ASN_DEBUG("Decoding %s as INTEGER (tm=%d)", |
| td->name, tag_mode); |
| |
| /* |
| * Check tags. |
| */ |
| rval = ber_check_tags(td, &ctx, |
| buf_ptr, size, tag_mode, &length, 0); |
| if(rval.code != RC_OK) |
| return rval; |
| |
| ASN_DEBUG("%s length is %d bytes", td->name, (int)length); |
| |
| /* |
| * Make sure we have this length. |
| */ |
| buf_ptr = ((char *)buf_ptr) + rval.consumed; |
| size -= rval.consumed; |
| if(length > (ber_tlv_len_t)size) { |
| rval.code = RC_WMORE; |
| rval.consumed = 0; |
| return rval; |
| } |
| |
| /* |
| * ASN.1 encoded INTEGER: buf_ptr, length |
| * Fill the Int, at the same time checking for overflow. |
| * If overflow occured, return with RC_FAIL. |
| */ |
| { |
| INTEGER_t tmp; |
| long l; |
| tmp.buf = (uint8_t *)buf_ptr; |
| tmp.size = length; |
| |
| if(asn1_INTEGER2long(&tmp, &l)) { |
| rval.code = RC_FAIL; |
| rval.consumed = 0; |
| return rval; |
| } |
| |
| *Int = l; |
| |
| /* |
| * Note that int might be shorter than long. |
| * This expression hopefully will be optimized away |
| * by compiler. |
| */ |
| if(sizeof(int) != sizeof(long) && (*Int != l)) { |
| *Int = 0; /* Safe value */ |
| rval.code = RC_FAIL; |
| rval.consumed = 0; |
| return rval; |
| } |
| } |
| |
| rval.code = RC_OK; |
| rval.consumed += length; |
| |
| ASN_DEBUG("Took %ld/%ld bytes to encode %s (%d)", |
| (long)rval.consumed, (long)length, td->name, *Int); |
| |
| return rval; |
| } |
| |
| /* |
| * Encode the NativeInteger using the standard INTEGER type DER encoder. |
| */ |
| der_enc_rval_t |
| NativeInteger_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) { |
| unsigned int Int = *(unsigned int *)ptr; /* Disable sign ext. */ |
| der_enc_rval_t erval; |
| INTEGER_t tmp; |
| |
| #ifdef WORDS_BIGENDIAN /* Opportunistic optimization */ |
| |
| tmp.buf = ∬ |
| tmp.size = sizeof(Int); |
| |
| #else /* Works even if WORDS_BIGENDIAN is not set where should've been */ |
| uint8_t buf[sizeof(int)]; |
| uint8_t *p; |
| |
| /* Prepare fake INTEGER */ |
| for(p = buf + sizeof(buf) - 1; p >= buf; p--, Int >>= 8) |
| *p = Int & 0xff; |
| |
| tmp.buf = buf; |
| tmp.size = sizeof(buf); |
| #endif /* WORDS_BIGENDIAN */ |
| |
| /* Encode fake INTEGER */ |
| erval = INTEGER_encode_der(sd, &tmp, tag_mode, tag, cb, app_key); |
| if(erval.encoded == -1) { |
| assert(erval.structure_ptr == &tmp); |
| erval.structure_ptr = ptr; |
| } |
| return erval; |
| } |
| |
| /* |
| * INTEGER specific human-readable output. |
| */ |
| int |
| NativeInteger_print(asn1_TYPE_descriptor_t *td, const void *sptr, int ilevel, |
| asn_app_consume_bytes_f *cb, void *app_key) { |
| const int *Int = (const int *)sptr; |
| char scratch[32]; /* Enough for 64-bit int */ |
| int ret; |
| |
| (void)td; /* Unused argument */ |
| (void)ilevel; /* Unused argument */ |
| |
| if(Int) { |
| ret = snprintf(scratch, sizeof(scratch), "%d", *Int); |
| assert(ret > 0 && ret < (int)sizeof(scratch)); |
| return cb(scratch, ret, app_key); |
| } else { |
| return cb("<absent>", 8, app_key); |
| } |
| } |
| |
| void |
| NativeInteger_free(asn1_TYPE_descriptor_t *td, void *ptr, int contents_only) { |
| |
| if(!td || !ptr) |
| return; |
| |
| ASN_DEBUG("Freeing %s as INTEGER (%d, %p, Native)", |
| td->name, contents_only, ptr); |
| |
| if(!contents_only) { |
| FREEMEM(ptr); |
| } |
| } |
| |