X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=libtomcrypt%2Fsrc%2Fpk%2Fasn1%2Fder%2Futf8%2Fder_length_utf8_string.c;fp=libtomcrypt%2Fsrc%2Fpk%2Fasn1%2Fder%2Futf8%2Fder_length_utf8_string.c;h=88f4355e3532b65c9e3c2971c1e68528ec896431;hb=66bc25938679f1d6a1d1200f329093d82a5e99b4;hp=0000000000000000000000000000000000000000;hpb=a52ee0733f420ca20224049260d6fc5cf7d8f621;p=zpackage diff --git a/libtomcrypt/src/pk/asn1/der/utf8/der_length_utf8_string.c b/libtomcrypt/src/pk/asn1/der/utf8/der_length_utf8_string.c new file mode 100644 index 0000000..88f4355 --- /dev/null +++ b/libtomcrypt/src/pk/asn1/der/utf8/der_length_utf8_string.c @@ -0,0 +1,102 @@ +/* LibTomCrypt, modular cryptographic library -- Tom St Denis + * + * LibTomCrypt is a library that provides various cryptographic + * algorithms in a highly modular and flexible manner. + * + * The library is free for all purposes without any express + * guarantee it works. + */ +#include "tomcrypt.h" + +/** + @file der_length_utf8_string.c + ASN.1 DER, get length of UTF8 STRING, Tom St Denis +*/ + +#ifdef LTC_DER + +/** Return the size in bytes of a UTF-8 character + @param c The UTF-8 character to measure + @return The size in bytes +*/ +unsigned long der_utf8_charsize(const wchar_t c) +{ + if (c <= 0x7F) { + return 1; + } else if (c <= 0x7FF) { + return 2; +#if LTC_WCHAR_MAX == 0xFFFF + } else { + return 3; + } +#else + } else if (c <= 0xFFFF) { + return 3; + } else { + return 4; + } +#endif +} + +/** + Test whether the given code point is valid character + @param c The UTF-8 character to test + @return 1 - valid, 0 - invalid +*/ +int der_utf8_valid_char(const wchar_t c) +{ + LTC_UNUSED_PARAM(c); +#if !defined(LTC_WCHAR_MAX) || LTC_WCHAR_MAX > 0xFFFF + if (c > 0x10FFFF) return 0; +#endif +#if LTC_WCHAR_MAX != 0xFFFF && LTC_WCHAR_MAX != 0xFFFFFFFF + if (c < 0) return 0; +#endif + return 1; +} + +/** + Gets length of DER encoding of UTF8 STRING + @param in The characters to measure the length of + @param noctets The number of octets in the string to encode + @param outlen [out] The length of the DER encoding for the given string + @return CRYPT_OK if successful +*/ +int der_length_utf8_string(const wchar_t *in, unsigned long noctets, unsigned long *outlen) +{ + unsigned long x, len; + + LTC_ARGCHK(in != NULL); + LTC_ARGCHK(outlen != NULL); + + len = 0; + for (x = 0; x < noctets; x++) { + if (!der_utf8_valid_char(in[x])) return CRYPT_INVALID_ARG; + len += der_utf8_charsize(in[x]); + } + + if (len < 128) { + /* 0C LL DD DD DD ... */ + *outlen = 2 + len; + } else if (len < 256) { + /* 0C 81 LL DD DD DD ... */ + *outlen = 3 + len; + } else if (len < 65536UL) { + /* 0C 82 LL LL DD DD DD ... */ + *outlen = 4 + len; + } else if (len < 16777216UL) { + /* 0C 83 LL LL LL DD DD DD ... */ + *outlen = 5 + len; + } else { + return CRYPT_INVALID_ARG; + } + + return CRYPT_OK; +} + +#endif + + +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */