=head1 NAME
-EVP_MD_CTX_new, EVP_MD_CTX_reset, EVP_MD_CTX_free, EVP_MD_CTX_copy_ex,
-EVP_MD_CTX_ctrl, EVP_DigestInit_ex, EVP_DigestUpdate, EVP_DigestFinal_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_sha1,
-EVP_sha224, EVP_sha256, EVP_sha384, EVP_sha512, EVP_mdc2,
-EVP_ripemd160, EVP_blake2b512, EVP_blake2s256, EVP_get_digestbyname,
-EVP_get_digestbynid, EVP_get_digestbyobj - EVP digest routines
+EVP_MD_CTX_new, EVP_MD_CTX_reset, EVP_MD_CTX_free, EVP_MD_CTX_copy,
+EVP_MD_CTX_copy_ex, EVP_MD_CTX_ctrl, EVP_MD_CTX_set_flags,
+EVP_MD_CTX_clear_flags, EVP_MD_CTX_test_flags,
+EVP_Digest, EVP_DigestInit_ex, EVP_DigestInit, EVP_DigestUpdate,
+EVP_DigestFinal_ex, EVP_DigestFinalXOF, EVP_DigestFinal,
+EVP_MD_type, EVP_MD_pkey_type, EVP_MD_size, EVP_MD_block_size, EVP_MD_flags,
+EVP_MD_CTX_md, EVP_MD_CTX_type, EVP_MD_CTX_size, EVP_MD_CTX_block_size,
+EVP_MD_CTX_md_data, EVP_MD_CTX_update_fn, EVP_MD_CTX_set_update_fn,
+EVP_md_null,
+EVP_get_digestbyname, EVP_get_digestbynid, EVP_get_digestbyobj,
+EVP_MD_CTX_pkey_ctx, EVP_MD_CTX_set_pkey_ctx - EVP digest routines
=head1 SYNOPSIS
int EVP_MD_CTX_reset(EVP_MD_CTX *ctx);
void EVP_MD_CTX_free(EVP_MD_CTX *ctx);
void EVP_MD_CTX_ctrl(EVP_MD_CTX *ctx, int cmd, int p1, void* p2);
+ void EVP_MD_CTX_set_flags(EVP_MD_CTX *ctx, int flags);
+ void EVP_MD_CTX_clear_flags(EVP_MD_CTX *ctx, int flags);
+ int EVP_MD_CTX_test_flags(const EVP_MD_CTX *ctx, int flags);
+ int EVP_Digest(const void *data, size_t count, unsigned char *md,
+ unsigned int *size, const EVP_MD *type, ENGINE *impl);
int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl);
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_DigestFinalXOF(EVP_MD_CTX *ctx, unsigned char *md, size_t len);
int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in);
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);
+ unsigned long EVP_MD_flags(const EVP_MD *md);
const EVP_MD *EVP_MD_CTX_md(const EVP_MD_CTX *ctx);
int EVP_MD_CTX_size(const EVP_MD *ctx);
int EVP_MD_CTX_block_size(const EVP_MD *ctx);
int EVP_MD_CTX_type(const EVP_MD *ctx);
+ void *EVP_MD_CTX_md_data(const EVP_MD_CTX *ctx);
+ int (*EVP_MD_CTX_update_fn(EVP_MD_CTX *ctx))(EVP_MD_CTX *ctx,
+ const void *data, size_t count);
+ void EVP_MD_CTX_set_update_fn(EVP_MD_CTX *ctx,
+ int (*update)(EVP_MD_CTX *ctx,
+ const void *data, size_t count));
const EVP_MD *EVP_md_null(void);
- const EVP_MD *EVP_md2(void);
- const EVP_MD *EVP_md5(void);
- const EVP_MD *EVP_sha1(void);
- const EVP_MD *EVP_mdc2(void);
- const EVP_MD *EVP_ripemd160(void);
- const EVP_MD *EVP_blake2b512(void);
- const EVP_MD *EVP_blake2s256(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);
const EVP_MD *EVP_get_digestbynid(int type);
const EVP_MD *EVP_get_digestbyobj(const ASN1_OBJECT *o);
+ EVP_PKEY_CTX *EVP_MD_CTX_pkey_ctx(const EVP_MD_CTX *ctx);
+ void EVP_MD_CTX_set_pkey_ctx(EVP_MD_CTX *ctx, EVP_PKEY_CTX *pctx);
+
=head1 DESCRIPTION
The EVP digest routines are a high level interface to message digests,
and should be used instead of the cipher-specific functions.
-EVP_MD_CTX_new() allocates, initializes and returns a digest context.
+=over 4
+
+=item EVP_MD_CTX_new()
+
+Allocates and returns a digest context.
+
+=item EVP_MD_CTX_reset()
+
+Resets the digest context B<ctx>. This can be used to reuse an already
+existing context.
+
+=item EVP_MD_CTX_free()
+
+Cleans up digest context B<ctx> and frees up the space allocated to it.
+
+=item EVP_MD_CTX_ctrl()
+
+Performs digest-specific control actions on context B<ctx>. The control command
+is indicated in B<cmd> and any additional arguments in B<p1> and B<p2>.
+EVP_MD_CTX_ctrl() must be called after EVP_DigestInit_ex(). Other restrictions
+may apply depending on the control type and digest implementation.
+See L</CONTROLS> below for more information.
+
+=item EVP_MD_CTX_set_flags(), EVP_MD_CTX_clear_flags(), EVP_MD_CTX_test_flags()
+
+Sets, clears and tests B<ctx> flags. See L</FLAGS> below for more information.
+
+=item EVP_Digest()
+
+A wrapper around the Digest Init_ex, Update and Final_ex functions.
+Hashes B<count> bytes of data at B<data> using a digest B<type> from ENGINE
+B<impl>. The digest value is placed in B<md> and its length is written at B<size>
+if the pointer is not NULL. At most B<EVP_MAX_MD_SIZE> bytes will be written.
+If B<impl> is NULL the default implementation of digest B<type> is used.
+
+=item EVP_DigestInit_ex()
+
+Sets up digest context B<ctx> to use a digest B<type> from ENGINE B<impl>.
+B<type> will typically be supplied by a function such as EVP_sha1(). If
+B<impl> is NULL then the default implementation of digest B<type> is used.
+
+=item EVP_DigestUpdate()
+
+Hashes B<cnt> bytes of data at B<d> into the digest context B<ctx>. This
+function can be called several times on the same B<ctx> to hash additional
+data.
+
+=item EVP_DigestFinal_ex()
+
+Retrieves the digest value from B<ctx> and places it in B<md>. If the B<s>
+parameter is not NULL then the number of bytes of data written (i.e. the
+length of the digest) will be written to the integer at B<s>, at most
+B<EVP_MAX_MD_SIZE> bytes will be written. After calling EVP_DigestFinal_ex()
+no additional calls to EVP_DigestUpdate() can be made, but
+EVP_DigestInit_ex() can be called to initialize a new digest operation.
+
+=item EVP_DigestFinalXOF()
+
+Interfaces to extendable-output functions, XOFs, such as SHAKE128 and SHAKE256.
+It retrieves the digest value from B<ctx> and places it in B<len>-sized <B>md.
+After calling this function no additional calls to EVP_DigestUpdate() can be
+made, but EVP_DigestInit_ex() can be called to initialize a new operation.
+
+=item EVP_MD_CTX_copy_ex()
+
+Can be used to copy the message digest state from B<in> to B<out>. This is
+useful if large amounts of data are to be hashed which only differ in the last
+few bytes.
+
+=item EVP_DigestInit()
+
+Behaves in the same way as EVP_DigestInit_ex() except it always uses the
+default digest implementation.
+
+=item EVP_DigestFinal()
+
+Similar to EVP_DigestFinal_ex() except the digest context B<ctx> is
+automatically cleaned up.
+
+=item EVP_MD_CTX_copy()
+
+Similar to EVP_MD_CTX_copy_ex() except the destination B<out> does not have to
+be initialized.
+
+=item EVP_MD_size(),
+EVP_MD_CTX_size()
+
+Return the size of the message digest when passed an B<EVP_MD> or an
+B<EVP_MD_CTX> structure, i.e. the size of the hash.
+
+=item EVP_MD_block_size(),
+EVP_MD_CTX_block_size()
+
+Return the block size of the message digest when passed an B<EVP_MD> or an
+B<EVP_MD_CTX> structure.
+
+=item EVP_MD_type(),
+EVP_MD_CTX_type()
+
+Return the NID of the OBJECT IDENTIFIER representing the given message digest
+when passed an B<EVP_MD> structure. For example, C<EVP_MD_type(EVP_sha1())>
+returns B<NID_sha1>. This function is normally used when setting ASN1 OIDs.
+
+=item EVP_MD_CTX_md_data()
+
+Return the digest method private data for the passed B<EVP_MD_CTX>.
+The space is allocated by OpenSSL and has the size originally set with
+EVP_MD_meth_set_app_datasize().
+
+=item EVP_MD_CTX_md()
-EVP_MD_CTX_reset() resets the digest context B<ctx>. This can be used
-to reuse an already existing context.
+Returns the B<EVP_MD> structure corresponding to the passed B<EVP_MD_CTX>. This
+will be the same B<EVP_MD> object originally passed to EVP_DigestInit_ex() (or
+other similar function) when the EVP_MD_CTX was first initialised. Note that
+where explicit fetch is in use (see L<EVP_MD_fetch(3)>) the value returned from
+this function will not have its reference count incremented and therefore it
+should not be used after the EVP_MD_CTX is freed.
-EVP_MD_CTX_free() cleans up digest context B<ctx> and frees up the
-space allocated to it.
+=item EVP_MD_CTX_set_update_fn()
-EVP_MD_CTX_ctrl() performs digest-specific control actions on context B<ctx>.
+Sets the update function for B<ctx> to B<update>.
+This is the function that is called by EVP_DigestUpdate. If not set, the
+update function from the B<EVP_MD> type specified at initialization is used.
-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
-function. B<type> will typically be supplied by a function such as EVP_sha1().
-If B<impl> is NULL then the default implementation of digest B<type> is used.
+=item EVP_MD_CTX_update_fn()
-EVP_DigestUpdate() hashes B<cnt> bytes of data at B<d> into the
-digest context B<ctx>. This function can be called several times on the
-same B<ctx> to hash additional data.
+Returns the update function for B<ctx>.
-EVP_DigestFinal_ex() retrieves the digest value from B<ctx> and places
-it in B<md>. If the B<s> parameter is not NULL then the number of
-bytes of data written (i.e. the length of the digest) will be written
-to the integer at B<s>, at most B<EVP_MAX_MD_SIZE> bytes will be written.
-After calling EVP_DigestFinal_ex() no additional calls to EVP_DigestUpdate()
-can be made, but EVP_DigestInit_ex() can be called to initialize a new
-digest operation.
+=item EVP_MD_flags()
-EVP_MD_CTX_copy_ex() can be used to copy the message digest state from
-B<in> to B<out>. This is useful if large amounts of data are to be
-hashed which only differ in the last few bytes. B<out> must be initialized
-before calling this function.
+Returns the B<md> flags. Note that these are different from the B<EVP_MD_CTX>
+ones. See L<EVP_MD_meth_set_flags(3)> for more information.
-EVP_DigestInit() behaves in the same way as EVP_DigestInit_ex() except
-the passed context B<ctx> does not have to be initialized, and it always
-uses the default digest implementation.
+=item EVP_MD_pkey_type()
-EVP_DigestFinal() is similar to EVP_DigestFinal_ex() except the digest
-context B<ctx> is automatically cleaned up.
+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>. Since digests and signature algorithms are no
+longer linked this function is only retained for compatibility reasons.
-EVP_MD_CTX_copy() is similar to EVP_MD_CTX_copy_ex() except the destination
-B<out> does not have to be initialized.
+=item EVP_md_null()
-EVP_MD_size() and EVP_MD_CTX_size() return the size of the message digest
-when passed an B<EVP_MD> or an B<EVP_MD_CTX> structure, i.e. the size of the
-hash.
+A "null" message digest that does nothing: i.e. the hash it returns is of zero
+length.
-EVP_MD_block_size() and EVP_MD_CTX_block_size() return the block size of the
-message digest when passed an B<EVP_MD> or an B<EVP_MD_CTX> structure.
+=item EVP_get_digestbyname(),
+EVP_get_digestbynid(),
+EVP_get_digestbyobj()
-EVP_MD_type() and EVP_MD_CTX_type() return the NID of the OBJECT IDENTIFIER
-representing the given message digest when passed an B<EVP_MD> structure.
-For example EVP_MD_type(EVP_sha1()) returns B<NID_sha1>. This function is
-normally used when setting ASN1 OIDs.
+Returns an B<EVP_MD> structure when passed a digest name, a digest B<NID> or an
+B<ASN1_OBJECT> structure respectively.
-EVP_MD_CTX_md() returns the B<EVP_MD> structure corresponding to the passed
-B<EVP_MD_CTX>.
+=item EVP_MD_CTX_pkey_ctx()
-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>. Since digests and signature algorithms
-are no longer linked this function is only retained for compatibility
-reasons.
+Returns the B<EVP_PKEY_CTX> assigned to B<ctx>. The returned pointer should not
+be freed by the caller.
-EVP_md2(), EVP_md5(), EVP_sha1(), EVP_sha224(), EVP_sha256(),
-EVP_sha384(), EVP_sha512(), EVP_mdc2(), EVP_ripemd160(), EVP_blake2b512(), and
-EVP_blake2s256() return B<EVP_MD> structures for the MD2, MD5, SHA1, SHA224,
-SHA256, SHA384, SHA512, MDC2, RIPEMD160, BLAKE2b-512, and BLAKE2s-256 digest
-algorithms respectively.
+=item EVP_MD_CTX_set_pkey_ctx()
-EVP_md_null() is a "null" message digest that does nothing: i.e. the hash it
-returns is of zero length.
+Assigns an B<EVP_PKEY_CTX> to B<EVP_MD_CTX>. This is usually used to provide
+a customized B<EVP_PKEY_CTX> to L<EVP_DigestSignInit(3)> or
+L<EVP_DigestVerifyInit(3)>. The B<pctx> passed to this function should be freed
+by the caller. A NULL B<pctx> pointer is also allowed to clear the B<EVP_PKEY_CTX>
+assigned to B<ctx>. In such case, freeing the cleared B<EVP_PKEY_CTX> or not
+depends on how the B<EVP_PKEY_CTX> is created.
-EVP_get_digestbyname(), EVP_get_digestbynid() and EVP_get_digestbyobj()
-return an B<EVP_MD> structure when passed a digest name, a digest NID or
-an ASN1_OBJECT structure respectively.
+=back
+
+=head1 CONTROLS
+
+EVP_MD_CTX_ctrl() can be used to send the following standard controls:
+
+=over 4
+
+=item EVP_MD_CTRL_MICALG
+
+Gets the digest Message Integrity Check algorithm string. This is used when
+creating S/MIME multipart/signed messages, as specified in RFC 3851.
+The string value is written to B<p2>.
+
+=item EVP_MD_CTRL_XOF_LEN
+
+This control sets the digest length for extendable output functions to B<p1>.
+Sending this control directly should not be necessary, the use of
+C<EVP_DigestFinalXOF()> is preferred.
+Currently used by SHAKE.
+
+=back
+
+=head1 FLAGS
+
+EVP_MD_CTX_set_flags(), EVP_MD_CTX_clear_flags() and EVP_MD_CTX_test_flags()
+can be used the manipulate and test these B<EVP_MD_CTX> flags:
+
+=over 4
+
+=item EVP_MD_CTX_FLAG_ONESHOT
+
+This flag instructs the digest to optimize for one update only, if possible.
+
+=for comment EVP_MD_CTX_FLAG_CLEANED is internal, don't mention it
+
+=for comment EVP_MD_CTX_FLAG_REUSE is internal, don't mention it
+
+=for comment We currently avoid documenting flags that are only bit holder:
+EVP_MD_CTX_FLAG_NON_FIPS_ALLOW, EVP_MD_CTX_FLAGS_PAD_*
+
+=item EVP_MD_CTX_FLAG_NO_INIT
+
+This flag instructs EVP_DigestInit() and similar not to initialise the
+implementation specific data.
+
+=item EVP_MD_CTX_FLAG_FINALISE
+
+Some functions such as EVP_DigestSign only finalise copies of internal
+contexts so additional data can be included after the finalisation call.
+This is inefficient if this functionality is not required, and can be
+disabled with this flag.
+
+=back
=head1 RETURN VALUES
-EVP_DigestInit_ex(), EVP_DigestUpdate() and EVP_DigestFinal_ex() return 1 for
+=over 4
+
+=item EVP_DigestInit_ex(),
+EVP_DigestUpdate(),
+EVP_DigestFinal_ex()
+
+Returns 1 for
success and 0 for failure.
-EVP_MD_CTX_ctrl() returns 1 if successful or 0 for failure.
+=item EVP_MD_CTX_ctrl()
+
+Returns 1 if successful or 0 for failure.
+
+=item EVP_MD_CTX_copy_ex()
+
+Returns 1 if successful or 0 for failure.
+
+=item EVP_MD_type(),
+EVP_MD_pkey_type()
+
+Returns the NID of the corresponding OBJECT IDENTIFIER or NID_undef if none
+exists.
-EVP_MD_CTX_copy_ex() returns 1 if successful or 0 for failure.
+=item EVP_MD_size(),
+EVP_MD_block_size(),
+EVP_MD_CTX_size(),
+EVP_MD_CTX_block_size()
-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.
+Returns 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.
+=item EVP_md_null()
-EVP_md_null(), EVP_md2(), EVP_md5(), EVP_sha1(),
-EVP_mdc2(), EVP_ripemd160(), EVP_blake2b512(), and EVP_blake2s256() return
-pointers to the corresponding EVP_MD structures.
+Returns a pointer to the B<EVP_MD> structure of the "null" message digest.
-EVP_get_digestbyname(), EVP_get_digestbynid() and EVP_get_digestbyobj()
-return either an B<EVP_MD> structure or NULL if an error occurs.
+=item EVP_get_digestbyname(),
+EVP_get_digestbynid(),
+EVP_get_digestbyobj()
+
+Returns either an B<EVP_MD> structure or NULL if an error occurs.
+
+=item EVP_MD_CTX_set_pkey_ctx()
+
+This function has no return value.
+
+=back
=head1 NOTES
preference to the low level interfaces. This is because the code then becomes
transparent to the digest used and much more flexible.
-New applications should use the SHA2 digest algorithms such as SHA256.
-The other digest algorithms are still in common use.
+New applications should use the SHA-2 (such as L<EVP_sha256(3)>) or the SHA-3
+digest algorithms (such as L<EVP_sha3_512(3)>). 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.
instead of initializing and cleaning it up on each call and allow non default
implementations of digests to be specified.
-If digest contexts are not cleaned up after use
+If digest contexts are not cleaned up after use,
memory leaks will occur.
EVP_MD_CTX_size(), EVP_MD_CTX_block_size(), EVP_MD_CTX_type(),
digest name passed on the command line.
#include <stdio.h>
+ #include <string.h>
#include <openssl/evp.h>
- main(int argc, char *argv[])
+ int main(int argc, char *argv[])
{
EVP_MD_CTX *mdctx;
const EVP_MD *md;
char mess1[] = "Test Message\n";
char mess2[] = "Hello World\n";
unsigned char md_value[EVP_MAX_MD_SIZE];
- int md_len, i;
+ unsigned int md_len, i;
if (argv[1] == NULL) {
printf("Usage: mdtest digestname\n");
=head1 SEE ALSO
+L<EVP_MD_meth_new(3)>,
L<dgst(1)>,
L<evp(7)>
-=head1 HISTORY
+The full list of digest algorithms are provided below.
-B<EVP_MD_CTX> became opaque in OpenSSL 1.1. Consequently, stack
-allocated B<EVP_MD_CTX>s are no longer supported.
+L<EVP_blake2b512(3)>,
+L<EVP_md2(3)>,
+L<EVP_md4(3)>,
+L<EVP_md5(3)>,
+L<EVP_mdc2(3)>,
+L<EVP_ripemd160(3)>,
+L<EVP_sha1(3)>,
+L<EVP_sha224(3)>,
+L<EVP_sha3_224(3)>,
+L<EVP_sm3(3)>,
+L<EVP_whirlpool(3)>
-EVP_MD_CTX_create() and EVP_MD_CTX_destroy() were renamed to
-EVP_MD_CTX_new() and EVP_MD_CTX_free() in OpenSSL 1.1.
+=head1 HISTORY
+
+The EVP_MD_CTX_create() and EVP_MD_CTX_destroy() functions were renamed to
+EVP_MD_CTX_new() and EVP_MD_CTX_free() in OpenSSL 1.1.0, respectively.
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. The legacy EVP_dss1()
-was removed in OpenSSL 1.1.0
+later, so now EVP_sha1() can be used with RSA and DSA.
+
+The EVP_dss1() function was removed in OpenSSL 1.1.0.
+
+The EVP_MD_CTX_set_pkey_ctx() function was added in 1.1.1.
=head1 COPYRIGHT
-Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
-Licensed under the OpenSSL license (the "License"). You may not use
+Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.
projects / openssl.git / blobdiff