Add ecdsa example program

include/polarssl/ecdsa.h

@@ -84,7 +84,8 @@ int ecdsa_verify( const ecp_group *grp,
                   const ecp_point *Q, const mpi *r, const mpi *s);
 
 /**
- * \brief           Compute ECDSA signature and write it to buffer
+ * \brief           Compute ECDSA signature and write it to buffer,
+ *                  serialized as defined in RFC 4492 page 20.
  *
  * \param ctx       ECDSA context
  * \param hash      Message hash

programs/.gitignore

@@ -9,6 +9,7 @@ hash/sha2sum
 pkey/dh_client
 pkey/dh_genprime
 pkey/dh_server
+pkey/ecdsa
 pkey/key_app
 pkey/key_app_writer
 pkey/mpi_demo

programs/Makefile

@@ -91,6 +91,10 @@ pkey/dh_server: pkey/dh_server.c ../library/libpolarssl.a
 	echo   "  CC    pkey/dh_server.c"
 	$(CC) $(CFLAGS) $(OFLAGS) pkey/dh_server.c   $(LDFLAGS) -o $@
 
+pkey/ecdsa: pkey/ecdsa.c ../library/libpolarssl.a
+	echo   "  CC    pkey/ecdsa.c"
+	$(CC) $(CFLAGS) $(OFLAGS) pkey/ecdsa.c       $(LDFLAGS) -o $@
+
 pkey/key_app: pkey/key_app.c ../library/libpolarssl.a
 	echo   "  CC    pkey/key_app.c"
 	$(CC) $(CFLAGS) $(OFLAGS) pkey/key_app.c   $(LDFLAGS) -o $@

programs/pkey/CMakeLists.txt

@@ -7,6 +7,9 @@ target_link_libraries(dh_genprime polarssl)
 add_executable(dh_server dh_server.c)
 target_link_libraries(dh_server polarssl)
 
+add_executable(ecdsa ecdsa.c)
+target_link_libraries(ecdsa polarssl)
+
 add_executable(key_app key_app.c)
 target_link_libraries(key_app polarssl)
 

programs/pkey/ecdsa.c

@@ -0,0 +1,196 @@
+/*
+ *  Example ECDSA program
+ *
+ *  Copyright (C) 2013, Brainspark B.V.
+ *
+ *  This file is part of PolarSSL (http://www.polarssl.org)
+ *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
+ *
+ *  All rights reserved.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "polarssl/config.h"
+
+#include "polarssl/entropy.h"
+#include "polarssl/ctr_drbg.h"
+#include "polarssl/ecdsa.h"
+
+#include <string.h>
+#include <stdio.h>
+
+/*
+ * Uncomment to force use of a specific curve
+#define ECPARAMS    POLARSSL_ECP_DP_SECP256R1
+ */
+
+#if !defined(ECPARAMS)
+#if defined(POLARSSL_ECP_DP_SECP192R1_ENABLED)
+#define ECPARAMS    POLARSSL_ECP_DP_SECP192R1
+#elif defined(POLARSSL_ECP_DP_SECP224R1_ENABLED)
+#define ECPARAMS    POLARSSL_ECP_DP_SECP224R1
+#elif defined(POLARSSL_ECP_DP_SECP256R1_ENABLED)
+#define ECPARAMS    POLARSSL_ECP_DP_SECP256R1
+#elif defined(POLARSSL_ECP_DP_SECP384R1_ENABLED)
+#define ECPARAMS    POLARSSL_ECP_DP_SECP384R1
+#elif defined(POLARSSL_ECP_DP_SECP521R1_ENABLED)
+#define ECPARAMS    POLARSSL_ECP_DP_SECP521R1
+#endif
+#endif /* !defined(ECPARAMS) */
+
+#if !defined(POLARSSL_BIGNUM_C) || !defined(POLARSSL_ECDSA_C) || \
+    !defined(POLARSSL_ENTROPY_C) || !defined(POLARSSL_CTR_DRBG_C) || \
+    !defined(ECPARAMS)
+int main( int argc, char *argv[] )
+{
+    ((void) argc);
+    ((void) argv);
+
+    printf("POLARSSL_BIGNUM_C and/or POLARSSL_ECDSA_C and/or "
+           "POLARSSL_ENTROPY_C and/or POLARSSL_CTR_DRBG_C not defined,"
+           "and/or not EC domain parameter available\n" );
+    return( 0 );
+}
+#else
+int main( int argc, char *argv[] )
+{
+    int ret;
+    ecdsa_context ctx_sign, ctx_verify;
+    entropy_context entropy;
+    ctr_drbg_context ctr_drbg;
+    unsigned char hash[] = "This should be the hash of a message.";
+    unsigned char sig[512];
+    size_t sig_len;
+    const char *pers = "ecdsa";
+    ((void) argv);
+
+    ecdsa_init( &ctx_sign );
+    ecdsa_init( &ctx_verify );
+
+    memset(sig, 0, sizeof( sig ) );
+    ret = 1;
+
+    if( argc != 1 )
+    {
+        printf( "usage: ecdsa\n" );
+
+#if defined(_WIN32)
+        printf( "\n" );
+#endif
+
+        goto exit;
+    }
+
+    /*
+     * Generate a key pair for signing
+     */
+    printf( "\n  . Seeding the random number generator..." );
+    fflush( stdout );
+
+    entropy_init( &entropy );
+    if( ( ret = ctr_drbg_init( &ctr_drbg, entropy_func, &entropy,
+                               (const unsigned char *) pers,
+                               strlen( pers ) ) ) != 0 )
+    {
+        printf( " failed\n  ! ctr_drbg_init returned %d\n", ret );
+        goto exit;
+    }
+
+    printf( " ok\n  . Generating key pair..." );
+    fflush( stdout );
+
+    if( ( ret = ecdsa_genkey( &ctx_sign, ECPARAMS,
+                              ctr_drbg_random, &ctr_drbg ) ) != 0 )
+    {
+        printf( " failed\n  ! ecdsa_genkey returned %d\n", ret );
+        goto exit;
+    }
+
+    printf( " ok (key size: %d bits)\n", (int) ctx_sign.grp.pbits );
+
+    /*
+     * Sign some message hash
+     */
+    printf( "  . Signing message..." );
+    fflush( stdout );
+
+    if( ( ret = ecdsa_write_signature( &ctx_sign,
+                                       hash, sizeof( hash ),
+                                       sig, &sig_len,
+                                       ctr_drbg_random, &ctr_drbg ) ) != 0 )
+    {
+        printf( " failed\n  ! ecdsa_genkey returned %d\n", ret );
+        goto exit;
+    }
+    printf( " ok\n" );
+
+    /*
+     * Signature is serialized as defined by RFC 4492 p. 20,
+     * but one can also access 'r' and 's' directly from the context
+     */
+#ifdef POLARSSL_FS_IO
+    mpi_write_file( "    r = ", &ctx_sign.r, 16, NULL );
+    mpi_write_file( "    s = ", &ctx_sign.s, 16, NULL );
+#endif
+
+    /*
+     * Transfer public information to verifying context
+     */
+    printf( "  . Preparing verification context..." );
+    fflush( stdout );
+
+    if( ( ret = ecp_use_known_dp( &ctx_verify.grp, ctx_sign.grp.id ) ) != 0 )
+    {
+        printf( " failed\n  ! ecp_use_known_dp returned %d\n", ret );
+        goto exit;
+    }
+
+    if( ( ret = ecp_copy( &ctx_verify.Q, &ctx_sign.Q ) ) != 0 )
+    {
+        printf( " failed\n  ! ecp_copy returned %d\n", ret );
+        goto exit;
+    }
+
+    ret = 0;
+
+    /*
+     * Verify signature
+     */
+    printf( " ok\n  . Verifying signature..." );
+    fflush( stdout );
+
+    if( ( ret = ecdsa_read_signature( &ctx_verify,
+                                      hash, sizeof( hash ),
+                                      sig, sig_len ) ) != 0 )
+    {
+        printf( " failed\n  ! ecdsa_read_signature returned %d\n", ret );
+        goto exit;
+    }
+
+    printf( " ok\n" );
+
+exit:
+
+#if defined(_WIN32)
+    printf( "  + Press Enter to exit this program.\n" );
+    fflush( stdout ); getchar();
+#endif
+
+    return( ret );
+}
+#endif /* POLARSSL_BIGNUM_C && POLARSSL_ECDSA_C &&
+          POLARSSL_ENTROPY_C && POLARSSL_CTR_DRBG_C &&
+          ECPARAMS */