Deprecate the low level Diffie-Hellman functions.

Use of the low level DH functions has been informally discouraged for a
long time.  We now formally deprecate them.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/11024)

2 files changed, 137 insertions, 111 deletions

diff --git a/include/openssl/dh.h b/include/openssl/dh.h
index e722ae42e1..b26e94e8e9 100644
--- a/include/openssl/dh.h
+++ b/include/openssl/dh.h
@@ -47,6 +47,7 @@ extern "C" {
 #   define DH_FLAG_NO_EXP_CONSTTIME 0x00
 #  endif
 
+#  ifndef OPENSSL_NO_DEPRECATED_3_0
 /*
  * If this flag is set the DH method is FIPS compliant and can be used in
  * FIPS mode. This is set in the validated module method. If an application
@@ -54,7 +55,7 @@ extern "C" {
  * result is compliant.
  */
 
-#  define DH_FLAG_FIPS_METHOD                     0x0400
+#   define DH_FLAG_FIPS_METHOD                     0x0400
 
 /*
  * If this flag is set the operations normally disabled in FIPS mode are
@@ -62,7 +63,8 @@ extern "C" {
  * usage is compliant.
  */
 
-#  define DH_FLAG_NON_FIPS_ALLOW                  0x0400
+#   define DH_FLAG_NON_FIPS_ALLOW                  0x0400
+#  endif
 
 /* Already defined in ossl_typ.h */
 /* typedef struct dh_st DH; */
@@ -70,29 +72,30 @@ extern "C" {
 
 DECLARE_ASN1_ITEM(DHparams)
 
-#  define DH_GENERATOR_2          2
-#  define DH_GENERATOR_3          3
-#  define DH_GENERATOR_5          5
+#  ifndef OPENSSL_NO_DEPRECATED_3_0
+#   define DH_GENERATOR_2          2
+#   define DH_GENERATOR_3          3
+#   define DH_GENERATOR_5          5
 
 /* DH_check error codes */
 /*
  * NB: These values must align with the equivalently named macros in
  * internal/ffc.h.
  */
-#  define DH_CHECK_P_NOT_PRIME            0x01
-#  define DH_CHECK_P_NOT_SAFE_PRIME       0x02
-#  define DH_UNABLE_TO_CHECK_GENERATOR    0x04
-#  define DH_NOT_SUITABLE_GENERATOR       0x08
-#  define DH_CHECK_Q_NOT_PRIME            0x10
-#  define DH_CHECK_INVALID_Q_VALUE        0x20
-#  define DH_CHECK_INVALID_J_VALUE        0x40
-#  define DH_MODULUS_TOO_SMALL            0x80
-#  define DH_MODULUS_TOO_LARGE            0x100
+#   define DH_CHECK_P_NOT_PRIME            0x01
+#   define DH_CHECK_P_NOT_SAFE_PRIME       0x02
+#   define DH_UNABLE_TO_CHECK_GENERATOR    0x04
+#   define DH_NOT_SUITABLE_GENERATOR       0x08
+#   define DH_CHECK_Q_NOT_PRIME            0x10
+#   define DH_CHECK_INVALID_Q_VALUE        0x20
+#   define DH_CHECK_INVALID_J_VALUE        0x40
+#   define DH_MODULUS_TOO_SMALL            0x80
+#   define DH_MODULUS_TOO_LARGE            0x100
 
 /* DH_check_pub_key error codes */
-#  define DH_CHECK_PUBKEY_TOO_SMALL       0x01
-#  define DH_CHECK_PUBKEY_TOO_LARGE       0x02
-#  define DH_CHECK_PUBKEY_INVALID         0x04
+#   define DH_CHECK_PUBKEY_TOO_SMALL       0x01
+#   define DH_CHECK_PUBKEY_TOO_LARGE       0x02
+#   define DH_CHECK_PUBKEY_INVALID         0x04
 
 /*
  * primes p where (p-1)/2 is prime too are called "safe"; we define this for
@@ -101,53 +104,58 @@ DECLARE_ASN1_ITEM(DHparams)
 #  define DH_CHECK_P_NOT_STRONG_PRIME     DH_CHECK_P_NOT_SAFE_PRIME
 
 /* DH parameter generation types used by EVP_PKEY_CTX_set_dh_paramgen_type() */
-#  define DH_PARAMGEN_TYPE_GENERATOR    0   /* Use a generator g */
-#  define DH_PARAMGEN_TYPE_FIPS_186_2   1   /* Use legacy FIPS186-2 standard */
-#  define DH_PARAMGEN_TYPE_FIPS_186_4   2   /* Use FIPS186-4 standard */
-
-#  define d2i_DHparams_fp(fp,x) \
-    (DH *)ASN1_d2i_fp((char *(*)())DH_new, \
-                      (char *(*)())d2i_DHparams, \
-                      (fp), \
-                      (unsigned char **)(x))
-#  define i2d_DHparams_fp(fp,x) \
-    ASN1_i2d_fp(i2d_DHparams,(fp), (unsigned char *)(x))
-#  define d2i_DHparams_bio(bp,x) \
-    ASN1_d2i_bio_of(DH, DH_new, d2i_DHparams, bp, x)
-#  define i2d_DHparams_bio(bp,x) \
-    ASN1_i2d_bio_of(DH,i2d_DHparams,bp,x)
-
-#  define d2i_DHxparams_fp(fp,x) \
-    (DH *)ASN1_d2i_fp((char *(*)())DH_new, \
-                      (char *(*)())d2i_DHxparams, \
-                      (fp), \
-                      (unsigned char **)(x))
-#  define i2d_DHxparams_fp(fp,x) \
-    ASN1_i2d_fp(i2d_DHxparams,(fp), (unsigned char *)(x))
-#  define d2i_DHxparams_bio(bp,x) \
-    ASN1_d2i_bio_of(DH, DH_new, d2i_DHxparams, bp, x)
-#  define i2d_DHxparams_bio(bp,x) \
-    ASN1_i2d_bio_of(DH, i2d_DHxparams, bp, x)
+#   define DH_PARAMGEN_TYPE_GENERATOR    0   /* Use a generator g */
+#   define DH_PARAMGEN_TYPE_FIPS_186_2   1   /* Use legacy FIPS186-2 standard */
+#   define DH_PARAMGEN_TYPE_FIPS_186_4   2   /* Use FIPS186-4 standard */
+
+#   define DH_CHECK_P_NOT_STRONG_PRIME     DH_CHECK_P_NOT_SAFE_PRIME
+
+#   define d2i_DHparams_fp(fp, x) \
+        (DH *)ASN1_d2i_fp((char *(*)())DH_new, \
+                          (char *(*)())d2i_DHparams, \
+                          (fp), \
+                          (unsigned char **)(x))
+#   define i2d_DHparams_fp(fp, x) \
+        ASN1_i2d_fp(i2d_DHparams,(fp), (unsigned char *)(x))
+#   define d2i_DHparams_bio(bp, x) \
+        ASN1_d2i_bio_of(DH, DH_new, d2i_DHparams, bp, x)
+#   define i2d_DHparams_bio(bp, x) \
+        ASN1_i2d_bio_of(DH, i2d_DHparams, bp, x)
+
+#   define d2i_DHxparams_fp(fp,x) \
+        (DH *)ASN1_d2i_fp((char *(*)())DH_new, \
+                          (char *(*)())d2i_DHxparams, \
+                          (fp), \
+                          (unsigned char **)(x))
+#   define i2d_DHxparams_fp(fp, x) \
+        ASN1_i2d_fp(i2d_DHxparams,(fp), (unsigned char *)(x))
+#   define d2i_DHxparams_bio(bp, x) \
+        ASN1_d2i_bio_of(DH, DH_new, d2i_DHxparams, bp, x)
+#   define i2d_DHxparams_bio(bp, x) \
+        ASN1_i2d_bio_of(DH, i2d_DHxparams, bp, x)
+#  endif
 
 DECLARE_ASN1_DUP_FUNCTION_name(DH, DHparams)
 
-const DH_METHOD *DH_OpenSSL(void);
+DEPRECATEDIN_3_0(const DH_METHOD *DH_OpenSSL(void))
 
-void DH_set_default_method(const DH_METHOD *meth);
-const DH_METHOD *DH_get_default_method(void);
-int DH_set_method(DH *dh, const DH_METHOD *meth);
-DH *DH_new_method(ENGINE *engine);
+DEPRECATEDIN_3_0(void DH_set_default_method(const DH_METHOD *meth))
+DEPRECATEDIN_3_0(const DH_METHOD *DH_get_default_method(void))
+DEPRECATEDIN_3_0(int DH_set_method(DH *dh, const DH_METHOD *meth))
+DEPRECATEDIN_3_0(DH *DH_new_method(ENGINE *engine))
 
 DH *DH_new(void);
 void DH_free(DH *dh);
 int DH_up_ref(DH *dh);
-int DH_bits(const DH *dh);
-int DH_size(const DH *dh);
-int DH_security_bits(const DH *dh);
-#  define DH_get_ex_new_index(l, p, newf, dupf, freef) \
-    CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, l, p, newf, dupf, freef)
-int DH_set_ex_data(DH *d, int idx, void *arg);
-void *DH_get_ex_data(DH *d, int idx);
+DEPRECATEDIN_3_0(int DH_bits(const DH *dh))
+DEPRECATEDIN_3_0(int DH_size(const DH *dh))
+DEPRECATEDIN_3_0(int DH_security_bits(const DH *dh))
+#  ifndef OPENSSL_NO_DEPRECATED_3_0
+#   define DH_get_ex_new_index(l, p, newf, dupf, freef) \
+        CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, l, p, newf, dupf, freef)
+#  endif
+DEPRECATEDIN_3_0(int DH_set_ex_data(DH *d, int idx, void *arg))
+DEPRECATEDIN_3_0(void *DH_get_ex_data(DH *d, int idx))
 
 /* Deprecated version */
 DEPRECATEDIN_0_9_8(DH *DH_generate_parameters(int prime_len, int generator,
@@ -156,24 +164,30 @@ DEPRECATEDIN_0_9_8(DH *DH_generate_parameters(int prime_len, int generator,
                                               void *cb_arg))
 
 /* New version */
-int DH_generate_parameters_ex(DH *dh, int prime_len, int generator,
-                              BN_GENCB *cb);
+DEPRECATEDIN_3_0(int DH_generate_parameters_ex(DH *dh, int prime_len,
+                                               int generator, BN_GENCB *cb))
 
-int DH_check_params_ex(const DH *dh);
-int DH_check_ex(const DH *dh);
-int DH_check_pub_key_ex(const DH *dh, const BIGNUM *pub_key);
+DEPRECATEDIN_3_0(int DH_check_params_ex(const DH *dh))
+DEPRECATEDIN_3_0(int DH_check_ex(const DH *dh))
+DEPRECATEDIN_3_0(int DH_check_pub_key_ex(const DH *dh, const BIGNUM *pub_key))
+/*
+ * TODO(3.0): deprecate DH_check_params once ssl/statem/statem_clnt.c is fixed.
+ */
 int DH_check_params(const DH *dh, int *ret);
-int DH_check(const DH *dh, int *codes);
-int DH_check_pub_key(const DH *dh, const BIGNUM *pub_key, int *codes);
-int DH_generate_key(DH *dh);
-int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh);
-int DH_compute_key_padded(unsigned char *key, const BIGNUM *pub_key, DH *dh);
+DEPRECATEDIN_3_0(int DH_check(const DH *dh, int *codes))
+DEPRECATEDIN_3_0(int DH_check_pub_key(const DH *dh, const BIGNUM *pub_key,
+                                      int *codes))
+DEPRECATEDIN_3_0(int DH_generate_key(DH *dh))
+DEPRECATEDIN_3_0(int DH_compute_key(unsigned char *key, const BIGNUM *pub_key,
+                                    DH *dh))
+DEPRECATEDIN_3_0(int DH_compute_key_padded(unsigned char *key,
+                                           const BIGNUM *pub_key, DH *dh))
 DECLARE_ASN1_ENCODE_FUNCTIONS_only(DH, DHparams)
 DECLARE_ASN1_ENCODE_FUNCTIONS_only(DH, DHxparams)
 #  ifndef OPENSSL_NO_STDIO
-int DHparams_print_fp(FILE *fp, const DH *x);
+DEPRECATEDIN_3_0(int DHparams_print_fp(FILE *fp, const DH *x))
 #  endif
-int DHparams_print(BIO *bp, const DH *x);
+DEPRECATEDIN_3_0(int DHparams_print(BIO *bp, const DH *x))
 
 /* RFC 5114 parameters */
 DH *DH_get_1024_160(void);
@@ -181,15 +195,17 @@ DH *DH_get_2048_224(void);
 DH *DH_get_2048_256(void);
 
 /* Named parameters, currently RFC7919 and RFC3526 */
+/* TODO(3.0): deprecate DH_new_by_nid() after converting ssl/s3_lib.c */
 DH *DH_new_by_nid(int nid);
-int DH_get_nid(DH *dh);
+DEPRECATEDIN_3_0(int DH_get_nid(DH *dh))
 
 #  ifndef OPENSSL_NO_CMS
 /* RFC2631 KDF */
-int DH_KDF_X9_42(unsigned char *out, size_t outlen,
-                 const unsigned char *Z, size_t Zlen,
-                 ASN1_OBJECT *key_oid,
-                 const unsigned char *ukm, size_t ukmlen, const EVP_MD *md);
+DEPRECATEDIN_3_0(int DH_KDF_X9_42(unsigned char *out, size_t outlen,
+                                  const unsigned char *Z, size_t Zlen,
+                                  ASN1_OBJECT *key_oid,
+                                  const unsigned char *ukm,
+                                  size_t ukmlen, const EVP_MD *md))
 #  endif
 
 void DH_get0_pqg(const DH *dh,
@@ -206,40 +222,53 @@ const BIGNUM *DH_get0_pub_key(const DH *dh);
 void DH_clear_flags(DH *dh, int flags);
 int DH_test_flags(const DH *dh, int flags);
 void DH_set_flags(DH *dh, int flags);
-ENGINE *DH_get0_engine(DH *d);
-long DH_get_length(const DH *dh);
-int DH_set_length(DH *dh, long length);
-
-DH_METHOD *DH_meth_new(const char *name, int flags);
-void DH_meth_free(DH_METHOD *dhm);
-DH_METHOD *DH_meth_dup(const DH_METHOD *dhm);
-const char *DH_meth_get0_name(const DH_METHOD *dhm);
-int DH_meth_set1_name(DH_METHOD *dhm, const char *name);
-int DH_meth_get_flags(const DH_METHOD *dhm);
-int DH_meth_set_flags(DH_METHOD *dhm, int flags);
-void *DH_meth_get0_app_data(const DH_METHOD *dhm);
-int DH_meth_set0_app_data(DH_METHOD *dhm, void *app_data);
-int (*DH_meth_get_generate_key(const DH_METHOD *dhm)) (DH *);
-int DH_meth_set_generate_key(DH_METHOD *dhm, int (*generate_key) (DH *));
-int (*DH_meth_get_compute_key(const DH_METHOD *dhm))
-        (unsigned char *key, const BIGNUM *pub_key, DH *dh);
-int DH_meth_set_compute_key(DH_METHOD *dhm,
-        int (*compute_key) (unsigned char *key, const BIGNUM *pub_key, DH *dh));
-int (*DH_meth_get_bn_mod_exp(const DH_METHOD *dhm))
-    (const DH *, BIGNUM *, const BIGNUM *, const BIGNUM *, const BIGNUM *,
-     BN_CTX *, BN_MONT_CTX *);
-int DH_meth_set_bn_mod_exp(DH_METHOD *dhm,
-    int (*bn_mod_exp) (const DH *, BIGNUM *, const BIGNUM *, const BIGNUM *,
-                       const BIGNUM *, BN_CTX *, BN_MONT_CTX *));
-int (*DH_meth_get_init(const DH_METHOD *dhm))(DH *);
-int DH_meth_set_init(DH_METHOD *dhm, int (*init)(DH *));
-int (*DH_meth_get_finish(const DH_METHOD *dhm)) (DH *);
-int DH_meth_set_finish(DH_METHOD *dhm, int (*finish) (DH *));
-int (*DH_meth_get_generate_params(const DH_METHOD *dhm))
-        (DH *, int, int, BN_GENCB *);
-int DH_meth_set_generate_params(DH_METHOD *dhm,
-        int (*generate_params) (DH *, int, int, BN_GENCB *));
-
+DEPRECATEDIN_3_0(ENGINE *DH_get0_engine(DH *d))
+DEPRECATEDIN_3_0(long DH_get_length(const DH *dh))
+DEPRECATEDIN_3_0(int DH_set_length(DH *dh, long length))
+
+DEPRECATEDIN_3_0(DH_METHOD *DH_meth_new(const char *name, int flags))
+DEPRECATEDIN_3_0(void DH_meth_free(DH_METHOD *dhm))
+DEPRECATEDIN_3_0(DH_METHOD *DH_meth_dup(const DH_METHOD *dhm))
+DEPRECATEDIN_3_0(const char *DH_meth_get0_name(const DH_METHOD *dhm))
+DEPRECATEDIN_3_0(int DH_meth_set1_name(DH_METHOD *dhm, const char *name))
+DEPRECATEDIN_3_0(int DH_meth_get_flags(const DH_METHOD *dhm))
+DEPRECATEDIN_3_0(int DH_meth_set_flags(DH_METHOD *dhm, int flags))
+DEPRECATEDIN_3_0(void *DH_meth_get0_app_data(const DH_METHOD *dhm))
+DEPRECATEDIN_3_0(int DH_meth_set0_app_data(DH_METHOD *dhm, void *app_data))
+DEPRECATEDIN_3_0(int (*DH_meth_get_generate_key(const DH_METHOD *dhm)) (DH *))
+DEPRECATEDIN_3_0(int DH_meth_set_generate_key(DH_METHOD *dhm,
+                                              int (*generate_key) (DH *)))
+DEPRECATEDIN_3_0(int (*DH_meth_get_compute_key(const DH_METHOD *dhm))
+                                               (unsigned char *key,
+                                               const BIGNUM *pub_key, DH *dh))
+DEPRECATEDIN_3_0(int DH_meth_set_compute_key(DH_METHOD *dhm,
+                                             int (*compute_key)
+                                                (unsigned char *key,
+                                                 const BIGNUM *pub_key,
+                                                 DH *dh)))
+DEPRECATEDIN_3_0(int (*DH_meth_get_bn_mod_exp(const DH_METHOD *dhm))
+                                                  (const DH *, BIGNUM *,
+                                                   const BIGNUM *,
+                                                   const BIGNUM *,
+                                                   const BIGNUM *, BN_CTX *,
+                                                   BN_MONT_CTX *))
+DEPRECATEDIN_3_0(int DH_meth_set_bn_mod_exp(DH_METHOD *dhm,
+                                            int (*bn_mod_exp)
+                                                (const DH *, BIGNUM *,
+                                                 const BIGNUM *, const BIGNUM *,
+                                                 const BIGNUM *, BN_CTX *,
+                                                 BN_MONT_CTX *)))
+DEPRECATEDIN_3_0(int (*DH_meth_get_init(const DH_METHOD *dhm))(DH *))
+DEPRECATEDIN_3_0(int DH_meth_set_init(DH_METHOD *dhm, int (*init)(DH *)))
+DEPRECATEDIN_3_0(int (*DH_meth_get_finish(const DH_METHOD *dhm)) (DH *))
+DEPRECATEDIN_3_0(int DH_meth_set_finish(DH_METHOD *dhm, int (*finish) (DH *)))
+DEPRECATEDIN_3_0(int (*DH_meth_get_generate_params(const DH_METHOD *dhm))
+                                                       (DH *, int, int,
+                                                        BN_GENCB *))
+DEPRECATEDIN_3_0(int DH_meth_set_generate_params(DH_METHOD *dhm,
+                                                 int (*generate_params)
+                                                     (DH *, int, int,
+                                                      BN_GENCB *)))
 
 #  define EVP_PKEY_CTX_set_dh_paramgen_prime_len(ctx, len) \
         EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DH, EVP_PKEY_OP_PARAMGEN, \
@@ -335,7 +364,6 @@ int EVP_PKEY_CTX_set_dh_pad(EVP_PKEY_CTX *ctx, int pad);
 #   define EVP_PKEY_DH_KDF_X9_42                          2
 #  endif
 
-
 #  ifdef  __cplusplus
 }
 #  endif
diff --git a/include/openssl/dsa.h b/include/openssl/dsa.h
index 5fe87bee1a..ac4d221b2d 100644
--- a/include/openssl/dsa.h
+++ b/include/openssl/dsa.h
@@ -178,10 +178,8 @@ DEPRECATEDIN_3_0(int DSA_print_fp(FILE *bp, const DSA *x, int off))
 /*
  * Convert DSA structure (key or just parameters) into DH structure (be
  * careful to avoid small subgroup attacks when using this!)
- *
- * TODO(3.0): figure out how to remove this monstrosity
  */
-DH *DSA_dup_DH(const DSA *r);
+DEPRECATEDIN_3_0(DH *DSA_dup_DH(const DSA *r))
 #  endif
 
 #  define EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, nbits) \