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Diffstat (limited to 'openssl/doc/crypto/sha.pod')
| -rw-r--r-- | openssl/doc/crypto/sha.pod | 64 |
1 files changed, 49 insertions, 15 deletions
diff --git a/openssl/doc/crypto/sha.pod b/openssl/doc/crypto/sha.pod index 94ab7bc72..0c9dbf2f3 100644 --- a/openssl/doc/crypto/sha.pod +++ b/openssl/doc/crypto/sha.pod @@ -2,29 +2,58 @@ =head1 NAME -SHA1, SHA1_Init, SHA1_Update, SHA1_Final - Secure Hash Algorithm +SHA1, SHA1_Init, SHA1_Update, SHA1_Final, SHA224, SHA224_Init, SHA224_Update, +SHA224_Final, SHA256, SHA256_Init, SHA256_Update, SHA256_Final, SHA384, +SHA384_Init, SHA384_Update, SHA384_Final, SHA512, SHA512_Init, SHA512_Update, +SHA512_Final - Secure Hash Algorithm =head1 SYNOPSIS #include <openssl/sha.h> - unsigned char *SHA1(const unsigned char *d, unsigned long n, - unsigned char *md); - int SHA1_Init(SHA_CTX *c); - int SHA1_Update(SHA_CTX *c, const void *data, - unsigned long len); + int SHA1_Update(SHA_CTX *c, const void *data, size_t len); int SHA1_Final(unsigned char *md, SHA_CTX *c); + unsigned char *SHA1(const unsigned char *d, size_t n, + unsigned char *md); + + int SHA224_Init(SHA256_CTX *c); + int SHA224_Update(SHA256_CTX *c, const void *data, size_t len); + int SHA224_Final(unsigned char *md, SHA256_CTX *c); + unsigned char *SHA224(const unsigned char *d, size_t n, + unsigned char *md); + + int SHA256_Init(SHA256_CTX *c); + int SHA256_Update(SHA256_CTX *c, const void *data, size_t len); + int SHA256_Final(unsigned char *md, SHA256_CTX *c); + unsigned char *SHA256(const unsigned char *d, size_t n, + unsigned char *md); + + int SHA384_Init(SHA512_CTX *c); + int SHA384_Update(SHA512_CTX *c, const void *data, size_t len); + int SHA384_Final(unsigned char *md, SHA512_CTX *c); + unsigned char *SHA384(const unsigned char *d, size_t n, + unsigned char *md); + + int SHA512_Init(SHA512_CTX *c); + int SHA512_Update(SHA512_CTX *c, const void *data, size_t len); + int SHA512_Final(unsigned char *md, SHA512_CTX *c); + unsigned char *SHA512(const unsigned char *d, size_t n, + unsigned char *md); =head1 DESCRIPTION +Applications should use the higher level functions +L<EVP_DigestInit(3)|EVP_DigestInit(3)> etc. instead of calling the hash +functions directly. + SHA-1 (Secure Hash Algorithm) is a cryptographic hash function with a 160 bit output. SHA1() computes the SHA-1 message digest of the B<n> bytes at B<d> and places it in B<md> (which must have space for SHA_DIGEST_LENGTH == 20 bytes of output). If B<md> is NULL, the digest -is placed in a static array. +is placed in a static array. Note: setting B<md> to NULL is B<not thread safe>. The following functions may be used if the message is not completely stored in memory: @@ -37,24 +66,29 @@ be hashed (B<len> bytes at B<data>). SHA1_Final() places the message digest in B<md>, which must have space for SHA_DIGEST_LENGTH == 20 bytes of output, and erases the B<SHA_CTX>. -Applications should use the higher level functions -L<EVP_DigestInit(3)|EVP_DigestInit(3)> -etc. instead of calling the hash functions directly. +The SHA224, SHA256, SHA384 and SHA512 families of functions operate in the +same way as for the SHA1 functions. Note that SHA224 and SHA256 use a +B<SHA256_CTX> object instead of B<SHA_CTX>. SHA384 and SHA512 use B<SHA512_CTX>. +The buffer B<md> must have space for the output from the SHA variant being used +(defined by SHA224_DIGEST_LENGTH, SHA256_DIGEST_LENGTH, SHA384_DIGEST_LENGTH and +SHA512_DIGEST_LENGTH). Also note that, as for the SHA1() function above, the +SHA224(), SHA256(), SHA384() and SHA512() functions are not thread safe if +B<md> is NULL. The predecessor of SHA-1, SHA, is also implemented, but it should be used only when backward compatibility is required. =head1 RETURN VALUES -SHA1() returns a pointer to the hash value. +SHA1(), SHA224(), SHA256(), SHA384() and SHA512() return a pointer to the hash +value. -SHA1_Init(), SHA1_Update() and SHA1_Final() return 1 for success, 0 otherwise. +SHA1_Init(), SHA1_Update() and SHA1_Final() and equivalent SHA224, SHA256, +SHA384 and SHA512 functions return 1 for success, 0 otherwise. =head1 CONFORMING TO -SHA: US Federal Information Processing Standard FIPS PUB 180 (Secure Hash -Standard), -SHA-1: US Federal Information Processing Standard FIPS PUB 180-1 (Secure Hash +US Federal Information Processing Standard FIPS PUB 180-4 (Secure Hash Standard), ANSI X9.30 |