X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=libtomcrypt%2Fsrc%2Fpk%2Fasn1%2Fder%2Fsequence%2Fder_decode_subject_public_key_info.c;fp=libtomcrypt%2Fsrc%2Fpk%2Fasn1%2Fder%2Fsequence%2Fder_decode_subject_public_key_info.c;h=d2d0811727f0c6179e0b1d659e56a19bb61076ca;hb=66bc25938679f1d6a1d1200f329093d82a5e99b4;hp=0000000000000000000000000000000000000000;hpb=a52ee0733f420ca20224049260d6fc5cf7d8f621;p=zpackage diff --git a/libtomcrypt/src/pk/asn1/der/sequence/der_decode_subject_public_key_info.c b/libtomcrypt/src/pk/asn1/der/sequence/der_decode_subject_public_key_info.c new file mode 100644 index 0000000..d2d0811 --- /dev/null +++ b/libtomcrypt/src/pk/asn1/der/sequence/der_decode_subject_public_key_info.c @@ -0,0 +1,112 @@ +/* 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_decode_subject_public_key_info.c + ASN.1 DER, encode a Subject Public Key structure --nmav +*/ + +#ifdef LTC_DER + +/* AlgorithmIdentifier := SEQUENCE { + * algorithm OBJECT IDENTIFIER, + * parameters ANY DEFINED BY algorithm + * } + * + * SubjectPublicKeyInfo := SEQUENCE { + * algorithm AlgorithmIdentifier, + * subjectPublicKey BIT STRING + * } + */ +/** + Decode a subject public key info + @param in The input buffer + @param inlen The length of the input buffer + @param algorithm One out of the enum #public_key_algorithms + @param public_key The buffer for the public key + @param public_key_len [in/out] The length of the public key buffer and the written length + @param parameters_type The parameters' type out of the enum ltc_asn1_type + @param parameters The parameters to include + @param parameters_len The number of parameters to include + @return CRYPT_OK on success +*/ +int der_decode_subject_public_key_info(const unsigned char *in, unsigned long inlen, + unsigned int algorithm, void* public_key, unsigned long* public_key_len, + unsigned long parameters_type, ltc_asn1_list* parameters, unsigned long parameters_len) +{ + int err; + unsigned long len; + oid_st oid; + unsigned char *tmpbuf; + unsigned long tmpoid[16]; + ltc_asn1_list alg_id[2]; + ltc_asn1_list subject_pubkey[2]; + + LTC_ARGCHK(in != NULL); + LTC_ARGCHK(inlen != 0); + LTC_ARGCHK(public_key_len != NULL); + + err = pk_get_oid(algorithm, &oid); + if (err != CRYPT_OK) { + return err; + } + + /* see if the OpenSSL DER format RSA public key will work */ + tmpbuf = XCALLOC(1, inlen); + if (tmpbuf == NULL) { + err = CRYPT_MEM; + goto LBL_ERR; + } + + /* this includes the internal hash ID and optional params (NULL in this case) */ + LTC_SET_ASN1(alg_id, 0, LTC_ASN1_OBJECT_IDENTIFIER, tmpoid, sizeof(tmpoid)/sizeof(tmpoid[0])); + LTC_SET_ASN1(alg_id, 1, (ltc_asn1_type)parameters_type, parameters, parameters_len); + + /* the actual format of the SSL DER key is odd, it stores a RSAPublicKey + * in a **BIT** string ... so we have to extract it then proceed to convert bit to octet + */ + LTC_SET_ASN1(subject_pubkey, 0, LTC_ASN1_SEQUENCE, alg_id, 2); + LTC_SET_ASN1(subject_pubkey, 1, LTC_ASN1_RAW_BIT_STRING, tmpbuf, inlen*8U); + + err=der_decode_sequence(in, inlen, subject_pubkey, 2UL); + if (err != CRYPT_OK) { + goto LBL_ERR; + } + + if ((alg_id[0].size != oid.OIDlen) || + XMEMCMP(oid.OID, alg_id[0].data, oid.OIDlen * sizeof(oid.OID[0])) != 0) { + /* OID mismatch */ + err = CRYPT_PK_INVALID_TYPE; + goto LBL_ERR; + } + + len = subject_pubkey[1].size/8; + if (*public_key_len > len) { + XMEMCPY(public_key, subject_pubkey[1].data, len); + *public_key_len = len; + } else { + *public_key_len = len; + err = CRYPT_BUFFER_OVERFLOW; + goto LBL_ERR; + } + + err = CRYPT_OK; + +LBL_ERR: + + XFREE(tmpbuf); + + return err; +} + +#endif + +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */