diff options
author | Ben Laurie <ben@openssl.org> | 2001-12-09 21:53:31 +0000 |
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committer | Ben Laurie <ben@openssl.org> | 2001-12-09 21:53:31 +0000 |
commit | ff3fa48fc79029d46f5285bdf9347b96f2262ce2 (patch) | |
tree | f74a1f8ddd6ecf86c7f217742f10dea32a3b89bb /doc/crypto/hmac.pod | |
parent | 87166e1fb6941280fc0827909d944b806461727d (diff) | |
download | openssl-new-ff3fa48fc79029d46f5285bdf9347b96f2262ce2.tar.gz |
Improve back compatibility.
Diffstat (limited to 'doc/crypto/hmac.pod')
-rw-r--r-- | doc/crypto/hmac.pod | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/doc/crypto/hmac.pod b/doc/crypto/hmac.pod index f86e7d7ddf..579bf9e8a0 100644 --- a/doc/crypto/hmac.pod +++ b/doc/crypto/hmac.pod @@ -13,11 +13,16 @@ authentication code int key_len, const unsigned char *d, int n, unsigned char *md, unsigned int *md_len); + void HMAC_CTX_init(HMAC_CTX *ctx); + void HMAC_Init(HMAC_CTX *ctx, const void *key, int key_len, const EVP_MD *md); + void HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int key_len, + const EVP_MD *md); void HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, int len); void HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len); + void HMAC_CTX_cleanup(HMAC_CTX *ctx); void HMAC_cleanup(HMAC_CTX *ctx); =head1 DESCRIPTION @@ -39,13 +44,31 @@ B<evp_md> can be EVP_sha1(), EVP_ripemd160() etc. B<key> and B<evp_md> may be B<NULL> if a key and hash function have been set in a previous call to HMAC_Init() for that B<HMAC_CTX>. -HMAC_cleanup() erases the key and other data from the B<HMAC_CTX>. +HMAC_CTX_init() initialises a B<HMAC_CTX> before first use. It must be +called. + +HMAC_CTX_cleanup() erases the key and other data from the B<HMAC_CTX> +and releases any associated resources. It must be called when an +B<HMAC_CTX> is no longer required. + +HMAC_cleanup() is an alias for HMAC_CTX_cleanup() included for back +compatibility with 0.9.6b, it is deprecated. The following functions may be used if the message is not completely stored in memory: HMAC_Init() initializes a B<HMAC_CTX> structure to use the hash -function B<evp_md> and the key B<key> which is B<key_len> bytes long. +function B<evp_md> and the key B<key> which is B<key_len> bytes +long. It is deprecated and only included for backward compatibility +with OpenSSL 0.9.6b. + +HMAC_Init_ex() initializes or reuses a B<HMAC_CTX> structure to use +the function B<evp_md> and key B<key>. Either can be NULL, in which +case the existing one will be reused. HMAC_CTX_init() must have been +called before the first use of an B<HMAC_CTX> in this +function. B<N.B. HMAC_Init() had this undocumented behaviour in +previous versions of OpenSSL - failure to switch to HMAC_Init_ex() in +programs that expect it will cause them to stop working>. HMAC_Update() can be called repeatedly with chunks of the message to be authenticated (B<len> bytes at B<data>). @@ -57,8 +80,8 @@ must have space for the hash function output. HMAC() returns a pointer to the message authentication code. -HMAC_Init(), HMAC_Update(), HMAC_Final() and HMAC_cleanup() do not -return values. +HMAC_CTX_init(), HMAC_Init_ex(), HMAC_Update(), HMAC_Final() and +HMAC_CTX_cleanup() do not return values. =head1 CONFORMING TO |