X-Git-Url: https://git.stg.codes/stg.git/blobdiff_plain/8c6fa3fbaccc22127280bf77a48fab5a3ee0716e..46b0747592074017ff0ea4b33d4a7194235886e5:/libs/smux/include/stg/ber_tlv_tag.h diff --git a/libs/smux/include/stg/ber_tlv_tag.h b/libs/smux/include/stg/ber_tlv_tag.h new file mode 100644 index 00000000..60e86686 --- /dev/null +++ b/libs/smux/include/stg/ber_tlv_tag.h @@ -0,0 +1,60 @@ +/*- + * Copyright (c) 2003, 2004 Lev Walkin . All rights reserved. + * Redistribution and modifications are permitted subject to BSD license. + */ +#ifndef _BER_TLV_TAG_H_ +#define _BER_TLV_TAG_H_ + +#ifdef __cplusplus +extern "C" { +#endif + +enum asn_tag_class { + ASN_TAG_CLASS_UNIVERSAL = 0, /* 0b00 */ + ASN_TAG_CLASS_APPLICATION = 1, /* 0b01 */ + ASN_TAG_CLASS_CONTEXT = 2, /* 0b10 */ + ASN_TAG_CLASS_PRIVATE = 3 /* 0b11 */ +}; +typedef unsigned ber_tlv_tag_t; /* BER TAG from Tag-Length-Value */ + +/* + * Tag class is encoded together with tag value for optimization purposes. + */ +#define BER_TAG_CLASS(tag) ((tag) & 0x3) +#define BER_TAG_VALUE(tag) ((tag) >> 2) +#define BER_TLV_CONSTRUCTED(tagptr) (((*(const uint8_t *)tagptr)&0x20)?1:0) + +#define BER_TAGS_EQUAL(tag1, tag2) ((tag1) == (tag2)) + +/* + * Several functions for printing the TAG in the canonical form + * (i.e. "[PRIVATE 0]"). + * Return values correspond to their libc counterparts (if any). + */ +ssize_t ber_tlv_tag_snprint(ber_tlv_tag_t tag, char *buf, size_t buflen); +ssize_t ber_tlv_tag_fwrite(ber_tlv_tag_t tag, FILE *); +char *ber_tlv_tag_string(ber_tlv_tag_t tag); + + +/* + * This function tries to fetch the tag from the input stream. + * RETURN VALUES: + * 0: More data expected than bufptr contains. + * -1: Fatal error deciphering tag. + * >0: Number of bytes used from bufptr. tag_r will contain the tag. + */ +ssize_t ber_fetch_tag(const void *bufptr, size_t size, ber_tlv_tag_t *tag_r); + +/* + * This function serializes the tag (T from TLV) in BER format. + * It always returns number of bytes necessary to represent the tag, + * it is a caller's responsibility to check the return value + * against the supplied buffer's size. + */ +size_t ber_tlv_tag_serialize(ber_tlv_tag_t tag, void *bufptr, size_t size); + +#ifdef __cplusplus +} +#endif + +#endif /* _BER_TLV_TAG_H_ */