AI_MD5_BER

AI_MD5_BER

Purpose:

This AI is similar to AI_MD5 except that it uses the ASN.1 BER format. This AI allows you to parse and create ASN.1 algorithm identifiers such as those used in PKCS #7 and other protocols. You call B_SetAlgorithmInfo to initialize an algorithm object from the encoded algorithm identifier. You call B_GetAlgorithmInfo with this AI to create an encoded algorithm identifier from an algorithm object that was created using AI_MD5, AI_MD5_BER, or AI_MD5_PEM. The OID for this algorithm, excluding the tag and length bytes, in decimal is “42, 134, 72, 134, 247, 13, 2, 5””.

Type of information this allows you to use:

the encoding of an algorithm identifier that specifies the MD5 message digest algorithm as defined in RFC 1321.

Format of info supplied to B_SetAlgorithmInfo:

pointer to an ITEM structure that gives the address and length of the BER-encoded algorithm identifier. The encoding is converted to DER before it is copied to the algorithm object. B_SetAlgorithmInfo returns BE_WRONG_ALGORITHM_INFO if the algorithm identifier specifies a message digest algorithm other than MD5.

Format of info returned by B_GetAlgorithmInfo:

pointer to an ITEM structure that gives the address and length of the DER-encoded algorithm identifier.

Crypto-C procedures to use with algorithm object:

B_DigestInit, B_DigestUpdate, and B_DigestFinal. Supply NULL_PTR for the keyObject argument in B_DigestInit.

Algorithm methods to include in application’s algorithm chooser:

AM_MD5.

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R S A B S A F E C r y p t o - C L i b r a r y R e f e r e n c e M a n u a l

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RSA Security manual AIMD5BER