octet_string.c

RSA加密/解密算法源码 asn1c-0.9.12

			*buf |= (ch&1) << bits_unused;
			break;
		default:
			st->bits_unused = bits_unused;
			return -1;
		}
	}

	if(bits_unused == 8) {
		st->size = buf - st->buf;
		st->bits_unused = 0;
	} else {
		st->size = buf - st->buf + 1;
		st->bits_unused = bits_unused;
	}

	assert(st->size <= _ns);
	st->buf[st->size] = 0;		/* Courtesy termination */

	return chunk_size;	/* Converted in full */
}

/*
 * Something like strtod(), but with stricter rules.
 */
static int
OS__strtoent(int base, const char *buf, const char *end, int32_t *ret_value) {
	int32_t val = 0;
	const char *p;

	for(p = buf; p < end; p++) {
		int ch = *p;
		if((val * base + base) < 0) return -1;	/* Strange huge value */
		switch(ch) {
		case 0x30: case 0x31: case 0x32: case 0x33: case 0x34: /*01234*/
		case 0x35: case 0x36: case 0x37: case 0x38: case 0x39: /*56789*/
			val = val * base + (ch - 0x30);
			break;
		case 0x41: case 0x42: case 0x43:	/* ABC */
		case 0x44: case 0x45: case 0x46:	/* DEF */
			val = val * base + (ch - 0x41 + 10);
			break;
		case 0x61: case 0x62: case 0x63:	/* abc */
		case 0x64: case 0x65: case 0x66:	/* def */
			val = val * base + (ch - 0x61 + 10);
			break;
		case 0x3b:	/* ';' */
			*ret_value = val;
			return (p - buf) + 1;
		default:
			return -1;	/* Character set error */
		}
	}

	/* Do not return value. It's an error we're talking about here. */
	return (p - buf);
}

/*
 * Convert from the plain UTF-8 format, expanding entity references: "2 &lt; 3"
 */
static ssize_t OCTET_STRING__convert_entrefs(void *sptr, const void *chunk_buf, size_t chunk_size, int have_more) {
	OCTET_STRING_t *st = (OCTET_STRING_t *)sptr;
	const char *p = (const char *)chunk_buf;
	const char *pend = p + chunk_size;
	uint8_t *buf;

	/* Reallocate buffer */
	ssize_t _ns = st->size + chunk_size;
	void *nptr = REALLOC(st->buf, _ns + 1);
	if(!nptr) return -1;
	st->buf = (uint8_t *)nptr;
	buf = st->buf + st->size;

	/*
	 * Convert series of 0 and 1 into the octet string.
	 */
	for(; p < pend; p++) {
		int ch = *(const unsigned char *)p;
		int len;	/* Length of the rest of the chunk */

		if(ch != 0x26 /* '&' */) {
			*buf++ = ch;
			continue;	/* That was easy... */
		}

		/*
		 * Process entity reference.
		 */
		len = chunk_size - (p - (const char *)chunk_buf);
		if(len == 1 /* "&" */) goto want_more;
		if(p[1] == 0x23 /* '#' */) {
			const char *pval;	/* Pointer to start of digits */
			int32_t val;		/* Entity reference value */
			int base;

			if(len == 2 /* "&#" */) goto want_more;
			if(p[2] == 0x78 /* 'x' */)
				pval = p + 3, base = 16;
			else
				pval = p + 2, base = 10;
			len = OS__strtoent(base, pval, p + len, &val);
			if(len == -1) {
				/* Invalid charset. Just copy verbatim. */
				*buf++ = ch;
				continue;
			}
			if(!len || pval[len-1] != 0x3b) goto want_more;
			assert(val > 0);
			p += (pval - p) + len - 1; /* Advance past entref */

			if(val < 0x80) {
				*buf++ = (char)val;
			} else if(val < 0x800) {
				*buf++ = 0xc0 | ((val >> 6));
				*buf++ = 0x80 | ((val & 0x3f));
			} else if(val < 0x10000) {
				*buf++ = 0xe0 | ((val >> 12));
				*buf++ = 0x80 | ((val >> 6) & 0x3f);
				*buf++ = 0x80 | ((val & 0x3f));
			} else if(val < 0x200000) {
				*buf++ = 0xf0 | ((val >> 18));
				*buf++ = 0x80 | ((val >> 12) & 0x3f);
				*buf++ = 0x80 | ((val >> 6) & 0x3f);
				*buf++ = 0x80 | ((val & 0x3f));
			} else if(val < 0x4000000) {
				*buf++ = 0xf8 | ((val >> 24));
				*buf++ = 0x80 | ((val >> 18) & 0x3f);
				*buf++ = 0x80 | ((val >> 12) & 0x3f);
				*buf++ = 0x80 | ((val >> 6) & 0x3f);
				*buf++ = 0x80 | ((val & 0x3f));
			} else {
				*buf++ = 0xfc | ((val >> 30) & 0x1);
				*buf++ = 0x80 | ((val >> 24) & 0x3f);
				*buf++ = 0x80 | ((val >> 18) & 0x3f);
				*buf++ = 0x80 | ((val >> 12) & 0x3f);
				*buf++ = 0x80 | ((val >> 6) & 0x3f);
				*buf++ = 0x80 | ((val & 0x3f));
			}
		} else {
			/*
			 * Ugly, limited parsing of &amp; &gt; &lt;
			 */
			char *sc = (char *)memchr(p, 0x3b, len > 5 ? 5 : len);
			if(!sc) goto want_more;
			if((sc - p) == 4
				&& p[1] == 0x61	/* 'a' */
				&& p[2] == 0x6d	/* 'm' */
				&& p[3] == 0x70	/* 'p' */) {
				*buf++ = 0x26;
				p = sc;
				continue;
			}
			if((sc - p) == 3) {
				if(p[1] == 0x6c) {
					*buf = 0x3c;	/* '<' */
				} else if(p[1] == 0x67) {
					*buf = 0x3e;	/* '>' */
				} else {
					/* Unsupported entity reference */
					*buf++ = ch;
					continue;
				}
				if(p[2] != 0x74) {
					/* Unsupported entity reference */
					*buf++ = ch;
					continue;
				}
				buf++;
				p = sc;
				continue;
			}
			/* Unsupported entity reference */
			*buf++ = ch;
		}

		continue;
	want_more:
		if(have_more) {
			/*
			 * We know that no more data (of the same type)
			 * is coming. Copy the rest verbatim.
			 */
			*buf++ = ch;
			continue;
		}
		chunk_size = (p - (const char *)chunk_buf);
		/* Processing stalled: need more data */
		break;
	}

	st->size = buf - st->buf;
	assert(st->size <= _ns);
	st->buf[st->size] = 0;		/* Courtesy termination */

	return chunk_size;	/* Converted in full */
}

/*
 * Decode OCTET STRING from the XML element's body.
 */
static asn_dec_rval_t
OCTET_STRING__decode_xer(asn_codec_ctx_t *opt_codec_ctx,
	asn_TYPE_descriptor_t *td, void **sptr,
	const char *opt_mname, void *buf_ptr, size_t size,
	int (*opt_unexpected_tag_decoder)
		(void *struct_ptr, const void *chunk_buf, size_t chunk_size),
	ssize_t (*body_receiver)
		(void *struct_ptr, const void *chunk_buf, size_t chunk_size,
			int have_more)
) {
	OCTET_STRING_t *st = (OCTET_STRING_t *)*sptr;
	asn_OCTET_STRING_specifics_t *specs = td->specifics
				? (asn_OCTET_STRING_specifics_t *)td->specifics
				: &asn_DEF_OCTET_STRING_specs;
	const char *xml_tag = opt_mname ? opt_mname : td->xml_tag;
	asn_struct_ctx_t *ctx;		/* Per-structure parser context */
	asn_dec_rval_t rval;		/* Return value from the decoder */
	int st_allocated;

	/*
	 * Create the string if does not exist.
	 */
	if(!st) {
		st = (OCTET_STRING_t *)CALLOC(1, specs->struct_size);
		*sptr = (void *)st;
		if(!st) goto sta_failed;
		st_allocated = 1;
	} else {
		st_allocated = 0;
	}
	if(!st->buf) {
		/* This is separate from above section */
		st->buf = (uint8_t *)CALLOC(1, 1);
		if(!st->buf) {
			if(st_allocated) {
				*sptr = 0;
				goto stb_failed;
			} else {
				goto sta_failed;
			}
		}
	}

	/* Restore parsing context */
	ctx = (asn_struct_ctx_t *)(((char *)*sptr) + specs->ctx_offset);

	return xer_decode_general(opt_codec_ctx, ctx, *sptr, xml_tag,
		buf_ptr, size, opt_unexpected_tag_decoder, body_receiver);

stb_failed:
	FREEMEM(st);
sta_failed:
	rval.code = RC_FAIL;
	rval.consumed = 0;
	return rval;
}

/*
 * Decode OCTET STRING from the hexadecimal data.
 */
asn_dec_rval_t
OCTET_STRING_decode_xer_hex(asn_codec_ctx_t *opt_codec_ctx,
	asn_TYPE_descriptor_t *td, void **sptr,
		const char *opt_mname, void *buf_ptr, size_t size) {
	return OCTET_STRING__decode_xer(opt_codec_ctx, td, sptr, opt_mname,
		buf_ptr, size, 0, OCTET_STRING__convert_hexadecimal);
}

/*
 * Decode OCTET STRING from the binary (0/1) data.
 */
asn_dec_rval_t
OCTET_STRING_decode_xer_binary(asn_codec_ctx_t *opt_codec_ctx,
	asn_TYPE_descriptor_t *td, void **sptr,
		const char *opt_mname, void *buf_ptr, size_t size) {
	return OCTET_STRING__decode_xer(opt_codec_ctx, td, sptr, opt_mname,
		buf_ptr, size, 0, OCTET_STRING__convert_binary);
}

/*
 * Decode OCTET STRING from the string (ASCII/UTF-8) data.
 */
asn_dec_rval_t
OCTET_STRING_decode_xer_utf8(asn_codec_ctx_t *opt_codec_ctx,
	asn_TYPE_descriptor_t *td, void **sptr,
		const char *opt_mname, void *buf_ptr, size_t size) {
	return OCTET_STRING__decode_xer(opt_codec_ctx, td, sptr, opt_mname,
		buf_ptr, size,
		OCTET_STRING__handle_control_chars,
		OCTET_STRING__convert_entrefs);
}


int
OCTET_STRING_print(asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
	asn_app_consume_bytes_f *cb, void *app_key) {
	static const char *h2c = "0123456789ABCDEF";
	const OCTET_STRING_t *st = (const OCTET_STRING_t *)sptr;
	char scratch[16 * 3 + 4];
	char *p = scratch;
	uint8_t *buf;
	uint8_t *end;
	size_t i;

	(void)td;	/* Unused argument */

	if(!st || !st->buf) return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;

	/*
	 * Dump the contents of the buffer in hexadecimal.
	 */
	buf = st->buf;
	end = buf + st->size;
	for(i = 0; buf < end; buf++, i++) {
		if(!(i % 16) && (i || st->size > 16)) {
			if(cb(scratch, p - scratch, app_key) < 0)
				return -1;
			_i_INDENT(1);
			p = scratch;
		}
		*p++ = h2c[(*buf >> 4) & 0x0F];
		*p++ = h2c[*buf & 0x0F];
		*p++ = 0x20;
	}

	if(p > scratch) {
		p--;	/* Remove the tail space */
		if(cb(scratch, p - scratch, app_key) < 0)
			return -1;
	}

	return 0;
}

int
OCTET_STRING_print_utf8(asn_TYPE_descriptor_t *td, const void *sptr,
		int ilevel, asn_app_consume_bytes_f *cb, void *app_key) {
	const OCTET_STRING_t *st = (const OCTET_STRING_t *)sptr;

	(void)td;	/* Unused argument */
	(void)ilevel;	/* Unused argument */

	if(st && st->buf) {
		return (cb(st->buf, st->size, app_key) < 0) ? -1 : 0;
	} else {
		return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;
	}
}

void
OCTET_STRING_free(asn_TYPE_descriptor_t *td, void *sptr, int contents_only) {
	OCTET_STRING_t *st = (OCTET_STRING_t *)sptr;
	asn_OCTET_STRING_specifics_t *specs = td->specifics
				? (asn_OCTET_STRING_specifics_t *)td->specifics
				: &asn_DEF_OCTET_STRING_specs;
	asn_struct_ctx_t *ctx = (asn_struct_ctx_t *)
					((char *)st + specs->ctx_offset);
	struct _stack *stck;

	if(!td || !st)
		return;

	ASN_DEBUG("Freeing %s as OCTET STRING", td->name);

	if(st->buf) {
		FREEMEM(st->buf);
	}

	/*
	 * Remove decode-time stack.
	 */
	stck = (struct _stack *)ctx->ptr;
	if(stck) {
		while(stck->tail) {
			struct _stack_el *sel = stck->tail;
			stck->tail = sel->prev;
			FREEMEM(sel);
		}
		FREEMEM(stck);
	}

	if(!contents_only) {
		FREEMEM(st);
	}
}

/*
 * Conversion routines.
 */
int
OCTET_STRING_fromBuf(OCTET_STRING_t *st, const char *str, int len) {
	void *buf;

	if(st == 0 || (str == 0 && len)) {
		errno = EINVAL;
		return -1;
	}

	/*
	 * Clear the OCTET STRING.
	 */
	if(str == NULL) {
		if(st->buf)
			FREEMEM(st->buf);
		st->size = 0;
		return 0;
	}

	/* Determine the original string size, if not explicitly given */
	if(len < 0)
		len = strlen(str);

	/* Allocate and fill the memory */
	buf = MALLOC(len + 1);
	if(buf == NULL) {
		return -1;
	} else {
		st->buf = (uint8_t *)buf;
		st->size = len;
	}

	memcpy(buf, str, len);
	st->buf[st->size] = '\0';	/* Couldn't use memcpy(len+1)! */

	return 0;
}

OCTET_STRING_t *
OCTET_STRING_new_fromBuf(asn_TYPE_descriptor_t *td, const char *str, int len) {
	asn_OCTET_STRING_specifics_t *specs = td->specifics
				? (asn_OCTET_STRING_specifics_t *)td->specifics
				: &asn_DEF_OCTET_STRING_specs;
	OCTET_STRING_t *st;

	st = (OCTET_STRING_t *)CALLOC(1, specs->struct_size);
	if(st && str && OCTET_STRING_fromBuf(st, str, len)) {
		free(st);
		st = NULL;
	}

	return st;
}