EVP_MD_CTX_init, EVP_MD_CTX_create, EVP_DigestInit_ex, EVP_DigestUpdate,
EVP_DigestFinal_ex, EVP_MD_CTX_cleanup, EVP_MD_CTX_destroy, EVP_MAX_MD_SIZE,
-EVP_MD_CTX_copy_ex EVP_MD_CTX_copy, EVP_MD_type, EVP_MD_pkey_type, EVP_MD_size,
-EVP_MD_block_size, EVP_MD_CTX_md, EVP_MD_CTX_size, EVP_MD_CTX_block_size, EVP_MD_CTX_type,
-EVP_md_null, EVP_md2, EVP_md5, EVP_sha, EVP_sha1, EVP_dss, EVP_dss1, EVP_mdc2,
+EVP_MD_CTX_copy_ex, EVP_DigestInit, EVP_DigestFinal, EVP_MD_CTX_copy, EVP_MD_type,
+EVP_MD_pkey_type, EVP_MD_size, EVP_MD_block_size, EVP_MD_CTX_md, EVP_MD_CTX_size,
+EVP_MD_CTX_block_size, EVP_MD_CTX_type, EVP_md_null, EVP_md2, EVP_md5, EVP_sha, EVP_sha1,
+EVP_sha224, EVP_sha256, EVP_sha384, EVP_sha512, EVP_dss, EVP_dss1, EVP_mdc2,
EVP_ripemd160, EVP_get_digestbyname, EVP_get_digestbynid, EVP_get_digestbyobj -
EVP digest routines
EVP_MD_CTX *EVP_MD_CTX_create(void);
int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl);
- int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *d, unsigned int cnt);
+ int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *d, size_t cnt);
int EVP_DigestFinal_ex(EVP_MD_CTX *ctx, unsigned char *md,
unsigned int *s);
int EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx);
void EVP_MD_CTX_destroy(EVP_MD_CTX *ctx);
- int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out,const EVP_MD_CTX *in);
+ int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out,const EVP_MD_CTX *in);
int EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type);
int EVP_DigestFinal(EVP_MD_CTX *ctx, unsigned char *md,
unsigned int *s);
- int EVP_MD_CTX_copy(EVP_MD_CTX *out,EVP_MD_CTX *in);
+ int EVP_MD_CTX_copy(EVP_MD_CTX *out,EVP_MD_CTX *in);
- #define EVP_MAX_MD_SIZE (16+20) /* The SSLv3 md5+sha1 type */
+ #define EVP_MAX_MD_SIZE 64 /* SHA512 */
+ int EVP_MD_type(const EVP_MD *md);
+ int EVP_MD_pkey_type(const EVP_MD *md);
+ int EVP_MD_size(const EVP_MD *md);
+ int EVP_MD_block_size(const EVP_MD *md);
- #define EVP_MD_type(e) ((e)->type)
- #define EVP_MD_pkey_type(e) ((e)->pkey_type)
- #define EVP_MD_size(e) ((e)->md_size)
- #define EVP_MD_block_size(e) ((e)->block_size)
-
- #define EVP_MD_CTX_md(e) (e)->digest)
- #define EVP_MD_CTX_size(e) EVP_MD_size((e)->digest)
+ const EVP_MD *EVP_MD_CTX_md(const EVP_MD_CTX *ctx);
+ #define EVP_MD_CTX_size(e) EVP_MD_size(EVP_MD_CTX_md(e))
#define EVP_MD_CTX_block_size(e) EVP_MD_block_size((e)->digest)
#define EVP_MD_CTX_type(e) EVP_MD_type((e)->digest)
const EVP_MD *EVP_mdc2(void);
const EVP_MD *EVP_ripemd160(void);
+ const EVP_MD *EVP_sha224(void);
+ const EVP_MD *EVP_sha256(void);
+ const EVP_MD *EVP_sha384(void);
+ const EVP_MD *EVP_sha512(void);
+
const EVP_MD *EVP_get_digestbyname(const char *name);
#define EVP_get_digestbynid(a) EVP_get_digestbyname(OBJ_nid2sn(a))
#define EVP_get_digestbyobj(a) EVP_get_digestbynid(OBJ_obj2nid(a))
The EVP digest routines are a high level interface to message digests.
-EVP_MD_CTX_init() initializes digest contet B<ctx>.
+EVP_MD_CTX_init() initializes digest context B<ctx>.
-EVP_MD_CTX_create() allocates, initializes and returns a digest contet.
+EVP_MD_CTX_create() allocates, initializes and returns a digest context.
EVP_DigestInit_ex() sets up digest context B<ctx> to use a digest
B<type> from ENGINE B<impl>. B<ctx> must be initialized before calling this
uses the default digest implementation.
EVP_DigestFinal() is similar to EVP_DigestFinal_ex() except the digest
-contet B<ctx> is automatically cleaned up.
+context B<ctx> is automatically cleaned up.
EVP_MD_CTX_copy() is similar to EVP_MD_CTX_copy_ex() except the destination
B<out> does not have to be initialized.
EVP_MD_pkey_type() returns the NID of the public key signing algorithm associated
with this digest. For example EVP_sha1() is associated with RSA so this will
-return B<NID_sha1WithRSAEncryption>. This "link" between digests and signature
-algorithms may not be retained in future versions of OpenSSL.
+return B<NID_sha1WithRSAEncryption>. Since digests and signature algorithms
+are no longer linked this function is only retained for compatibility
+reasons.
-EVP_md2(), EVP_md5(), EVP_sha(), EVP_sha1(), EVP_mdc2() and EVP_ripemd160()
-return B<EVP_MD> structures for the MD2, MD5, SHA, SHA1, MDC2 and RIPEMD160 digest
-algorithms respectively. The associated signature algorithm is RSA in each case.
+EVP_md2(), EVP_md5(), EVP_sha(), EVP_sha1(), EVP_sha224(), EVP_sha256(),
+EVP_sha384(), EVP_sha512(), EVP_mdc2() and EVP_ripemd160() return B<EVP_MD>
+structures for the MD2, MD5, SHA, SHA1, SHA224, SHA256, SHA384, SHA512, MDC2
+and RIPEMD160 digest algorithms respectively.
EVP_dss() and EVP_dss1() return B<EVP_MD> structures for SHA and SHA1 digest
-algorithms but using DSS (DSA) for the signature algorithm.
+algorithms but using DSS (DSA) for the signature algorithm. Note: there is
+no need to use these pseudo-digests in OpenSSL 1.0.0 and later, they are
+however retained for compatibility.
EVP_md_null() is a "null" message digest that does nothing: i.e. the hash it
returns is of zero length.
EVP_MD_type(), EVP_MD_pkey_type() and EVP_MD_type() return the NID of the
corresponding OBJECT IDENTIFIER or NID_undef if none exists.
-EVP_MD_size(), EVP_MD_block_size(), EVP_MD_CTX_size(e), EVP_MD_size(),
-EVP_MD_CTX_block_size() and EVP_MD_block_size() return the digest or block
-size in bytes.
+EVP_MD_size(), EVP_MD_block_size(), EVP_MD_CTX_size() and
+EVP_MD_CTX_block_size() return the digest or block size in bytes.
EVP_md_null(), EVP_md2(), EVP_md5(), EVP_sha(), EVP_sha1(), EVP_dss(),
EVP_dss1(), EVP_mdc2() and EVP_ripemd160() return pointers to the
preference to the low level interfaces. This is because the code then becomes
transparent to the digest used and much more flexible.
-SHA1 is the digest of choice for new applications. The other digest algorithms
-are still in common use.
+New applications should use the SHA2 digest algorithms such as SHA256.
+The other digest algorithms are still in common use.
For most applications the B<impl> parameter to EVP_DigestInit_ex() will be
set to NULL to use the default digest implementation.
-The functions EVP_DigestInit(), EVP_DigestFinal() and EVP_MD_CTX_copy() are
+The functions EVP_DigestInit(), EVP_DigestFinal() and EVP_MD_CTX_copy() are
obsolete but are retained to maintain compatibility with existing code. New
-applications should use EVP_DigestInit_ex(), EVP_DigestFinal_ex() and
+applications should use EVP_DigestInit_ex(), EVP_DigestFinal_ex() and
EVP_MD_CTX_copy_ex() because they can efficiently reuse a digest context
instead of initializing and cleaning it up on each call and allow non default
implementations of digests to be specified.
In OpenSSL 0.9.7 and later if digest contexts are not cleaned up after use
-memory leaks will occur.
+memory leaks will occur.
+
+Stack allocation of EVP_MD_CTX structures is common, for example:
+
+ EVP_MD_CTX mctx;
+ EVP_MD_CTX_init(&mctx);
+
+This will cause binary compatibility issues if the size of EVP_MD_CTX
+structure changes (this will only happen with a major release of OpenSSL).
+Applications wishing to avoid this should use EVP_MD_CTX_create() instead:
+
+ EVP_MD_CTX *mctx;
+ mctx = EVP_MD_CTX_create();
+
=head1 EXAMPLE
main(int argc, char *argv[])
{
- EVP_MD_CTX mdctx;
+ EVP_MD_CTX *mdctx;
const EVP_MD *md;
char mess1[] = "Test Message\n";
char mess2[] = "Hello World\n";
exit(1);
}
- EVP_MD_CTX_init(&mdctx);
- EVP_DigestInit_ex(&mdctx, md, NULL);
- EVP_DigestUpdate(&mdctx, mess1, strlen(mess1));
- EVP_DigestUpdate(&mdctx, mess2, strlen(mess2));
- EVP_DigestFinal_ex(&mdctx, md_value, &md_len);
- EVP_MD_CTX_cleanup(&mdctx);
+ mdctx = EVP_MD_CTX_create();
+ EVP_DigestInit_ex(mdctx, md, NULL);
+ EVP_DigestUpdate(mdctx, mess1, strlen(mess1));
+ EVP_DigestUpdate(mdctx, mess2, strlen(mess2));
+ EVP_DigestFinal_ex(mdctx, md_value, &md_len);
+ EVP_MD_CTX_destroy(mdctx);
printf("Digest is: ");
- for(i = 0; i < md_len; i++) printf("%02x", md_value[i]);
+ for(i = 0; i < md_len; i++)
+ printf("%02x", md_value[i]);
printf("\n");
- }
-
-=head1 BUGS
-The link between digests and signing algorithms results in a situation where
-EVP_sha1() must be used with RSA and EVP_dss1() must be used with DSS
-even though they are identical digests.
+ /* Call this once before exit. */
+ EVP_cleanup();
+ exit(0);
+ }
=head1 SEE ALSO
-L<evp(3)|evp(3)>, L<hmac(3)|hmac(3)>, L<md2(3)|md2(3)>,
-L<md5(3)|md5(3)>, L<mdc2(3)|mdc2(3)>, L<ripemd(3)|ripemd(3)>,
-L<sha(3)|sha(3)>, L<dgst(1)|dgst(1)>
+L<dgst(1)|dgst(1)>,
+L<evp(3)|evp(3)>
=head1 HISTORY
EVP_md_null(), EVP_md2(), EVP_md5(), EVP_sha(), EVP_sha1(),
EVP_dss(), EVP_dss1(), EVP_mdc2() and EVP_ripemd160() were
-changed to return truely const EVP_MD * in OpenSSL 0.9.7.
+changed to return truly const EVP_MD * in OpenSSL 0.9.7.
+
+The link between digests and signing algorithms was fixed in OpenSSL 1.0 and
+later, so now EVP_sha1() can be used with RSA and DSA; there is no need to
+use EVP_dss1() any more.
+
+OpenSSL 1.0 and later does not include the MD2 digest algorithm in the
+default configuration due to its security weaknesses.
=cut
projects / openssl.git / blobdiff