PEM encoding for GMP RSA public and private keys
authorAndreas Steffen <andreas.steffen@strongswan.org>
Sun, 4 Apr 2010 17:11:18 +0000 (19:11 +0200)
committerAndreas Steffen <andreas.steffen@strongswan.org>
Sun, 4 Apr 2010 17:11:18 +0000 (19:11 +0200)
src/libstrongswan/plugins/gmp/gmp_rsa_private_key.c
src/libstrongswan/plugins/gmp/gmp_rsa_public_key.c
src/libstrongswan/plugins/pem/Makefile.am
src/libstrongswan/plugins/pem/pem_encoder.c [new file with mode: 0644]
src/libstrongswan/plugins/pem/pem_encoder.h [new file with mode: 0644]
src/libstrongswan/plugins/pem/pem_plugin.c

index 211ce41..ac2bad5 100644 (file)
@@ -404,7 +404,13 @@ static bool get_encoding(private_gmp_rsa_private_key_t *this,
                                                 key_encoding_type_t type, chunk_t *encoding)
 {
        chunk_t n, e, d, p, q, exp1, exp2, coeff;
-       bool success;
+       bool success, pem = FALSE;
+
+       if (type == KEY_PRIV_PEM)
+       {
+               pem = TRUE;
+               type = KEY_PRIV_ASN1_DER;
+       }
 
        n = gmp_mpz_to_chunk(this->n);
        e = gmp_mpz_to_chunk(this->e);
@@ -430,6 +436,15 @@ static bool get_encoding(private_gmp_rsa_private_key_t *this,
        chunk_clear(&exp2);
        chunk_clear(&coeff);
 
+       if (pem && success)
+       {
+               chunk_t asn1_encoding = *encoding;
+
+               success = lib->encoding->encode(lib->encoding, KEY_PRIV_PEM, NULL,
+                                                                       encoding, KEY_PART_RSA_PRIV_ASN1_DER,
+                                                                       asn1_encoding, KEY_PART_END);
+               chunk_clear(&asn1_encoding);
+       }
        return success;
 }
 
index d207671..111533b 100644 (file)
@@ -396,7 +396,13 @@ static bool get_encoding(private_gmp_rsa_public_key_t *this,
                                                 key_encoding_type_t type, chunk_t *encoding)
 {
        chunk_t n, e;
-       bool success;
+       bool success, pem = FALSE;
+
+       if (type == KEY_PUB_PEM)
+       {
+               pem = TRUE;
+               type = KEY_PUB_SPKI_ASN1_DER;
+       }
 
        n = gmp_mpz_to_chunk(this->n);
        e = gmp_mpz_to_chunk(this->e);
@@ -406,6 +412,15 @@ static bool get_encoding(private_gmp_rsa_public_key_t *this,
        chunk_free(&n);
        chunk_free(&e);
 
+       if (pem && success)
+       {
+               chunk_t asn1_encoding = *encoding;
+
+               success = lib->encoding->encode(lib->encoding, KEY_PUB_PEM, NULL,
+                                                                       encoding, KEY_PART_RSA_PUB_ASN1_DER,
+                                                                       asn1_encoding, KEY_PART_END);
+               chunk_clear(&asn1_encoding);
+       }
        return success;
 }
 
index f43423a..b815b1e 100644 (file)
@@ -11,6 +11,7 @@ endif
 
 libstrongswan_pem_la_SOURCES = \
        pem_plugin.h pem_plugin.c \
-       pem_builder.c pem_builder.h
+       pem_builder.c pem_builder.h \
+       pem_encoder.c pem_encoder.h
 
 libstrongswan_pem_la_LDFLAGS = -module -avoid-version
diff --git a/src/libstrongswan/plugins/pem/pem_encoder.c b/src/libstrongswan/plugins/pem/pem_encoder.c
new file mode 100644 (file)
index 0000000..65073f5
--- /dev/null
@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2010 Andreas Steffen
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+#include "pem_encoder.h"
+
+#define BYTES_PER_LINE 48
+
+/**
+ * See header.
+ */
+bool pem_encoder_encode(key_encoding_type_t type, chunk_t *encoding,
+                                               va_list args)
+{
+       chunk_t asn1;
+       char *label;
+       u_char *pos;
+       size_t len, written, pem_chars, pem_lines;
+
+       switch (type)
+       {
+               case KEY_PUB_PEM:
+                       if (!key_encoding_args(args, KEY_PART_RSA_PUB_ASN1_DER,
+                                                                  &asn1, KEY_PART_END))
+                       {
+                               return FALSE;
+                       }
+                       label ="PUBLIC KEY";
+                       break;
+               case KEY_PRIV_PEM:
+                       if (!key_encoding_args(args, KEY_PART_RSA_PRIV_ASN1_DER,
+                                                                  &asn1, KEY_PART_END))
+                       {
+                               return FALSE;
+                       }
+                       label ="RSA PRIVATE KEY";
+                       break;
+               default:
+                       return FALSE;
+       }
+
+       /* compute and allocate maximum size of PEM object */
+       pem_chars = 4*(asn1.len + 2)/3;
+       pem_lines = (asn1.len + BYTES_PER_LINE - 1) / BYTES_PER_LINE; 
+       *encoding = chunk_alloc(5 + 2*(6 + strlen(label) + 6) + 3 + pem_chars + pem_lines);
+       pos = encoding->ptr;
+       len = encoding->len;
+
+       /* write PEM header */
+       written = snprintf(pos, len, "-----BEGIN %s-----\n", label);
+       pos += written;
+       len -= written; 
+
+       /* write PEM body */
+       while (pem_lines--)
+       {
+               chunk_t asn1_line, pem_line;
+
+               asn1_line = chunk_create(asn1.ptr, min(asn1.len, BYTES_PER_LINE));
+               asn1.ptr += asn1_line.len;
+               asn1.len -= asn1_line.len;
+               pem_line =  chunk_to_base64(asn1_line, pos);
+               pos += pem_line.len;
+               len -= pem_line.len;
+               *pos = '\n';
+               pos++;
+               len--;
+       }
+
+       /* write PEM trailer */
+       written = snprintf(pos, len, "-----END %s-----", label);
+       pos += written;
+       len -= written; 
+
+       /* replace termination null character with newline */
+    *pos = '\n';
+       pos++;
+       len--;
+
+       /* compute effective length of PEM object */
+       encoding->len = pos - encoding->ptr;
+       return TRUE;
+}
+
diff --git a/src/libstrongswan/plugins/pem/pem_encoder.h b/src/libstrongswan/plugins/pem/pem_encoder.h
new file mode 100644 (file)
index 0000000..a181133
--- /dev/null
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2010 Andreas Steffen
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup pem_encoder pem_encoder
+ * @{ @ingroup pem_p
+ */
+
+#ifndef PEM_ENCODER_H_
+#define PEM_ENCODER_H_
+
+#include <credentials/keys/key_encoding.h>
+
+/**
+ * Encoding from ASN.1 to PEM format.
+ */
+bool pem_encoder_encode(key_encoding_type_t type, chunk_t *encoding,
+                                               va_list args);
+
+#endif /** PEM_ENCODER_H_ @}*/
+
index b769872..810901b 100644 (file)
@@ -16,7 +16,9 @@
 #include "pem_plugin.h"
 
 #include <library.h>
+
 #include "pem_builder.h"
+#include "pem_encoder.h"
 
 typedef struct private_pem_plugin_t private_pem_plugin_t;
 
@@ -100,6 +102,9 @@ plugin_t *pem_plugin_create()
        lib->creds->add_builder(lib->creds, CRED_CERTIFICATE, CERT_PLUTO_CRL,
                                                        (builder_function_t)pem_certificate_load);
 
+       /* register PEM encoder */
+       lib->encoding->add_encoder(lib->encoding, pem_encoder_encode);
+
        return &this->public.plugin;
 }