pkey: additional EC related options

Add options to change the parameter encoding and point conversions for EC
public and private keys.  These options are present in the deprecated 'ec'
utility.
Reviewed-by: NDmitry Belyavskiy <beldmit@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/11113)

apps/pkey.c

@@ -15,11 +15,29 @@
 #include <openssl/err.h>
 #include <openssl/evp.h>
 
+#ifndef OPENSSL_NO_EC
+# include <openssl/ec.h>
+
+static OPT_PAIR ec_conv_forms[] = {
+    {"compressed", POINT_CONVERSION_COMPRESSED},
+    {"uncompressed", POINT_CONVERSION_UNCOMPRESSED},
+    {"hybrid", POINT_CONVERSION_HYBRID},
+    {NULL}
+};
+
+static OPT_PAIR ec_param_enc[] = {
+    {"named_curve", OPENSSL_EC_NAMED_CURVE},
+    {"explicit", 0},
+    {NULL}
+};
+#endif
+
 typedef enum OPTION_choice {
     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
     OPT_INFORM, OPT_OUTFORM, OPT_PASSIN, OPT_PASSOUT, OPT_ENGINE,
     OPT_IN, OPT_OUT, OPT_PUBIN, OPT_PUBOUT, OPT_TEXT_PUB,
-    OPT_TEXT, OPT_NOOUT, OPT_MD, OPT_TRADITIONAL, OPT_CHECK, OPT_PUB_CHECK
+    OPT_TEXT, OPT_NOOUT, OPT_MD, OPT_TRADITIONAL, OPT_CHECK, OPT_PUB_CHECK,
+    OPT_EC_PARAM_ENC, OPT_EC_CONV_FORM
 } OPTION_CHOICE;
 
 const OPTIONS pkey_options[] = {
@@ -31,6 +49,10 @@ const OPTIONS pkey_options[] = {
     {"check", OPT_CHECK, '-', "Check key consistency"},
     {"pubcheck", OPT_PUB_CHECK, '-', "Check public key consistency"},
     {"", OPT_MD, '-', "Any supported cipher"},
+    {"ec_param_enc", OPT_EC_PARAM_ENC, 's',
+     "Specifies the way the ec parameters are encoded"},
+    {"ec_conv_form", OPT_EC_CONV_FORM, 's',
+     "Specifies the point conversion form "},
 
     OPT_SECTION("Input"),
     {"in", OPT_IN, 's', "Input key"},
@@ -65,6 +87,12 @@ int pkey_main(int argc, char **argv)
     int informat = FORMAT_PEM, outformat = FORMAT_PEM;
     int pubin = 0, pubout = 0, pubtext = 0, text = 0, noout = 0, ret = 1;
     int private = 0, traditional = 0, check = 0, pub_check = 0;
+#ifndef OPENSSL_NO_EC
+    EC_KEY *eckey;
+    int ec_asn1_flag = OPENSSL_EC_NAMED_CURVE, new_ec_asn1_flag = 0;
+    int i, new_ec_form = 0;
+    point_conversion_form_t ec_form = POINT_CONVERSION_UNCOMPRESSED;
+#endif
 
     prog = opt_init(argc, argv, pkey_options);
     while ((o = opt_next()) != OPT_EOF) {
@@ -128,6 +156,27 @@ int pkey_main(int argc, char **argv)
         case OPT_MD:
             if (!opt_cipher(opt_unknown(), &cipher))
                 goto opthelp;
+            break;
+        case OPT_EC_CONV_FORM:
+#ifdef OPENSSL_NO_EC
+            goto opthelp;
+#else
+            if (!opt_pair(opt_arg(), ec_conv_forms, &i))
+                goto opthelp;
+            new_ec_form = 1;
+            ec_form = i;
+            break;
+#endif
+        case OPT_EC_PARAM_ENC:
+#ifdef OPENSSL_NO_EC
+            goto opthelp;
+#else
+            if (!opt_pair(opt_arg(), ec_param_enc, &i))
+                goto opthelp;
+            new_ec_asn1_flag = 1;
+            ec_asn1_flag = i;
+            break;
+#endif
         }
     }
     argc = opt_num_rest();
@@ -154,6 +203,24 @@ int pkey_main(int argc, char **argv)
     if (pkey == NULL)
         goto end;
 
+#ifndef OPENSSL_NO_EC
+    /*
+     * TODO: remove this and use a set params call with a 'pkeyopt' command
+     * line option instead.
+     */
+    if (new_ec_form || new_ec_asn1_flag) {
+        if ((eckey = EVP_PKEY_get0_EC_KEY(pkey)) == NULL) {
+            ERR_print_errors(bio_err);
+            goto end;
+        }
+        if (new_ec_form)
+            EC_KEY_set_conv_form(eckey, ec_form);
+
+        if (new_ec_asn1_flag)
+            EC_KEY_set_asn1_flag(eckey, ec_asn1_flag);
+    }
+#endif
+
     if (check || pub_check) {
         int r;
         EVP_PKEY_CTX *ctx;

doc/man1/openssl-pkey.pod.in

@@ -28,6 +28,8 @@ B<openssl> B<pkey>
 [B<-pubout>]
 [B<-check>]
 [B<-pubcheck>]
+[B<-ec_conv_form> I<arg>]
+[B<-ec_param_enc> I<arg>]
 {- $OpenSSL::safe::opt_engine_synopsis -}
 
 =for openssl ifdef engine
@@ -114,6 +116,30 @@ components.
 This option checks the correctness of either a public key or the public component
 of a key pair.
 
+=item B<-ec_conv_form> I<arg>
+
+This option only applies to elliptic curve based public and private keys.
+
+This specifies how the points on the elliptic curve are converted
+into octet strings. Possible values are: B<compressed> (the default
+value), B<uncompressed> and B<hybrid>. For more information regarding
+the point conversion forms please read the X9.62 standard.
+B<Note> Due to patent issues the B<compressed> option is disabled
+by default for binary curves and can be enabled by defining
+the preprocessor macro B<OPENSSL_EC_BIN_PT_COMP> at compile time.
+
+=item B<-ec_param_enc> I<arg>
+
+This option only applies to elliptic curve based public and private keys.
+
+This specifies how the elliptic curve parameters are encoded.
+Possible value are: B<named_curve>, i.e. the ec parameters are
+specified by an OID, or B<explicit> where the ec parameters are
+explicitly given (see RFC 3279 for the definition of the
+EC parameters structures). The default value is B<named_curve>.
+B<Note> the B<implicitlyCA> alternative, as specified in RFC 3279,
+is currently not implemented in OpenSSL.
+
 {- $OpenSSL::safe::opt_engine_item -}
 
 =back
@@ -144,6 +170,14 @@ To just output the public part of a private key:
 
  openssl pkey -in key.pem -pubout -out pubkey.pem
 
+To change the EC parameters encoding to B<explicit>:
+
+ openssl pkey -in key.pem -ec_param_enc explicit -out keyout.pem
+
+To change the EC point conversion form to B<compressed>:
+
+ openssl pkey -in key.pem -ec_conv_form compressed -out keyout.pem
+
 =head1 SEE ALSO
 
 L<openssl(1)>,