diff options
Diffstat (limited to 'libtomcrypt/src/pk/asn1/der/octet')
3 files changed, 230 insertions, 0 deletions
diff --git a/libtomcrypt/src/pk/asn1/der/octet/der_decode_octet_string.c b/libtomcrypt/src/pk/asn1/der/octet/der_decode_octet_string.c new file mode 100644 index 0000000..b937e63 --- /dev/null +++ b/libtomcrypt/src/pk/asn1/der/octet/der_decode_octet_string.c @@ -0,0 +1,91 @@ +/* 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. + * + * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com + */ +#include "tomcrypt.h" + +/** + @file der_decode_octet_string.c + ASN.1 DER, encode a OCTET STRING, Tom St Denis +*/ + + +#ifdef LTC_DER + +/** + Store a OCTET STRING + @param in The DER encoded OCTET STRING + @param inlen The size of the DER OCTET STRING + @param out [out] The array of octets stored (one per char) + @param outlen [in/out] The number of octets stored + @return CRYPT_OK if successful +*/ +int der_decode_octet_string(const unsigned char *in, unsigned long inlen, + unsigned char *out, unsigned long *outlen) +{ + unsigned long x, y, len; + + LTC_ARGCHK(in != NULL); + LTC_ARGCHK(out != NULL); + LTC_ARGCHK(outlen != NULL); + + /* must have header at least */ + if (inlen < 2) { + return CRYPT_INVALID_PACKET; + } + + /* check for 0x04 */ + if ((in[0] & 0x1F) != 0x04) { + return CRYPT_INVALID_PACKET; + } + x = 1; + + /* decode the length */ + if (in[x] & 0x80) { + /* valid # of bytes in length are 1,2,3 */ + y = in[x] & 0x7F; + if ((y == 0) || (y > 3) || ((x + y) > inlen)) { + return CRYPT_INVALID_PACKET; + } + + /* read the length in */ + len = 0; + ++x; + while (y--) { + len = (len << 8) | in[x++]; + } + } else { + len = in[x++] & 0x7F; + } + + /* is it too long? */ + if (len > *outlen) { + *outlen = len; + return CRYPT_BUFFER_OVERFLOW; + } + + if (len + x > inlen) { + return CRYPT_INVALID_PACKET; + } + + /* read the data */ + for (y = 0; y < len; y++) { + out[y] = in[x++]; + } + + *outlen = y; + + return CRYPT_OK; +} + +#endif + +/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/octet/der_decode_octet_string.c,v $ */ +/* $Revision: 1.3 $ */ +/* $Date: 2006/06/16 21:53:41 $ */ diff --git a/libtomcrypt/src/pk/asn1/der/octet/der_encode_octet_string.c b/libtomcrypt/src/pk/asn1/der/octet/der_encode_octet_string.c new file mode 100644 index 0000000..fe0f163 --- /dev/null +++ b/libtomcrypt/src/pk/asn1/der/octet/der_encode_octet_string.c @@ -0,0 +1,86 @@ +/* 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. + * + * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com + */ +#include "tomcrypt.h" + +/** + @file der_encode_octet_string.c + ASN.1 DER, encode a OCTET STRING, Tom St Denis +*/ + + +#ifdef LTC_DER + +/** + Store an OCTET STRING + @param in The array of OCTETS to store (one per char) + @param inlen The number of OCTETS to store + @param out [out] The destination for the DER encoded OCTET STRING + @param outlen [in/out] The max size and resulting size of the DER OCTET STRING + @return CRYPT_OK if successful +*/ +int der_encode_octet_string(const unsigned char *in, unsigned long inlen, + unsigned char *out, unsigned long *outlen) +{ + unsigned long x, y, len; + int err; + + LTC_ARGCHK(in != NULL); + LTC_ARGCHK(out != NULL); + LTC_ARGCHK(outlen != NULL); + + /* get the size */ + if ((err = der_length_octet_string(inlen, &len)) != CRYPT_OK) { + return err; + } + + /* too big? */ + if (len > *outlen) { + *outlen = len; + return CRYPT_BUFFER_OVERFLOW; + } + + /* encode the header+len */ + x = 0; + out[x++] = 0x04; + if (inlen < 128) { + out[x++] = (unsigned char)inlen; + } else if (inlen < 256) { + out[x++] = 0x81; + out[x++] = (unsigned char)inlen; + } else if (inlen < 65536UL) { + out[x++] = 0x82; + out[x++] = (unsigned char)((inlen>>8)&255); + out[x++] = (unsigned char)(inlen&255); + } else if (inlen < 16777216UL) { + out[x++] = 0x83; + out[x++] = (unsigned char)((inlen>>16)&255); + out[x++] = (unsigned char)((inlen>>8)&255); + out[x++] = (unsigned char)(inlen&255); + } else { + return CRYPT_INVALID_ARG; + } + + /* store octets */ + for (y = 0; y < inlen; y++) { + out[x++] = in[y]; + } + + /* retun length */ + *outlen = x; + + return CRYPT_OK; +} + +#endif + +/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/octet/der_encode_octet_string.c,v $ */ +/* $Revision: 1.4 $ */ +/* $Date: 2006/12/04 21:34:03 $ */ diff --git a/libtomcrypt/src/pk/asn1/der/octet/der_length_octet_string.c b/libtomcrypt/src/pk/asn1/der/octet/der_length_octet_string.c new file mode 100644 index 0000000..3caf352 --- /dev/null +++ b/libtomcrypt/src/pk/asn1/der/octet/der_length_octet_string.c @@ -0,0 +1,53 @@ +/* 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. + * + * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com + */ +#include "tomcrypt.h" + +/** + @file der_length_octet_string.c + ASN.1 DER, get length of OCTET STRING, Tom St Denis +*/ + +#ifdef LTC_DER +/** + Gets length of DER encoding of OCTET STRING + @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_octet_string(unsigned long noctets, unsigned long *outlen) +{ + LTC_ARGCHK(outlen != NULL); + + if (noctets < 128) { + /* 04 LL DD DD DD ... */ + *outlen = 2 + noctets; + } else if (noctets < 256) { + /* 04 81 LL DD DD DD ... */ + *outlen = 3 + noctets; + } else if (noctets < 65536UL) { + /* 04 82 LL LL DD DD DD ... */ + *outlen = 4 + noctets; + } else if (noctets < 16777216UL) { + /* 04 83 LL LL LL DD DD DD ... */ + *outlen = 5 + noctets; + } else { + return CRYPT_INVALID_ARG; + } + + return CRYPT_OK; +} + +#endif + + +/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/octet/der_length_octet_string.c,v $ */ +/* $Revision: 1.2 $ */ +/* $Date: 2006/03/31 14:15:35 $ */ |