version 0.3.33

[fms.git] / libs / libtomcrypt / pk / rsa / rsa_import.c

diff --git a/libs/libtomcrypt/pk/rsa/rsa_import.c b/libs/libtomcrypt/pk/rsa/rsa_import.c
new file mode 100644 (file)
index 0000000..7b12fd9
--- /dev/null
+++ b/libs/libtomcrypt/pk/rsa/rsa_import.c
@@ -0,0 +1,143 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
+ */
+#include "tomcrypt.h"
+
+/**
+  @file rsa_import.c
+  Import a PKCS RSA key, Tom St Denis
+*/  
+
+#ifdef MRSA
+
+/**
+  Import an RSAPublicKey or RSAPrivateKey [two-prime only, only support >= 1024-bit keys, defined in PKCS #1 v2.1]
+  @param in      The packet to import from
+  @param inlen   It's length (octets)
+  @param key     [out] Destination for newly imported key
+  @return CRYPT_OK if successful, upon error allocated memory is freed
+*/
+int rsa_import(const unsigned char *in, unsigned long inlen, rsa_key *key)
+{
+   int           err;
+   void         *zero;
+   unsigned char *tmpbuf;
+   unsigned long  t, x, y, z, tmpoid[16];
+   ltc_asn1_list ssl_pubkey_hashoid[2];
+   ltc_asn1_list ssl_pubkey[2];
+
+   LTC_ARGCHK(in          != NULL);
+   LTC_ARGCHK(key         != NULL);
+   LTC_ARGCHK(ltc_mp.name != NULL);
+
+   /* init key */
+   if ((err = mp_init_multi(&key->e, &key->d, &key->N, &key->dQ, 
+                            &key->dP, &key->qP, &key->p, &key->q, NULL)) != CRYPT_OK) {
+      return err;
+   }
+
+   /* see if the OpenSSL DER format RSA public key will work */
+   tmpbuf = XCALLOC(1, MAX_RSA_SIZE*8);
+   if (tmpbuf == NULL) {
+       err = CRYPT_MEM;
+       goto LBL_ERR;
+   }
+
+   /* this includes the internal hash ID and optional params (NULL in this case) */
+   LTC_SET_ASN1(ssl_pubkey_hashoid, 0, LTC_ASN1_OBJECT_IDENTIFIER, tmpoid,                sizeof(tmpoid)/sizeof(tmpoid[0]));   
+   LTC_SET_ASN1(ssl_pubkey_hashoid, 1, LTC_ASN1_NULL,              NULL,                  0);
+
+   /* the actual format of the SSL DER key is odd, it stores a RSAPublicKey in a **BIT** string ... so we have to extract it
+      then proceed to convert bit to octet 
+    */
+   LTC_SET_ASN1(ssl_pubkey, 0,         LTC_ASN1_SEQUENCE,          &ssl_pubkey_hashoid,   2);
+   LTC_SET_ASN1(ssl_pubkey, 1,         LTC_ASN1_BIT_STRING,        tmpbuf,                MAX_RSA_SIZE*8);
+
+   if (der_decode_sequence(in, inlen,
+                           ssl_pubkey, 2UL) == CRYPT_OK) {
+
+      /* ok now we have to reassemble the BIT STRING to an OCTET STRING.  Thanks OpenSSL... */
+      for (t = y = z = x = 0; x < ssl_pubkey[1].size; x++) {
+          y = (y << 1) | tmpbuf[x];
+          if (++z == 8) {
+             tmpbuf[t++] = (unsigned char)y;
+             y           = 0;
+             z           = 0;
+          }
+      }
+
+      /* now it should be SEQUENCE { INTEGER, INTEGER } */
+      if ((err = der_decode_sequence_multi(tmpbuf, t,
+                                           LTC_ASN1_INTEGER, 1UL, key->N, 
+                                           LTC_ASN1_INTEGER, 1UL, key->e, 
+                                           LTC_ASN1_EOL,     0UL, NULL)) != CRYPT_OK) {
+         XFREE(tmpbuf);
+         goto LBL_ERR;
+      }
+      XFREE(tmpbuf);
+      key->type = PK_PUBLIC;
+      return CRYPT_OK;
+   }
+   XFREE(tmpbuf);
+
+   /* not SSL public key, try to match against PKCS #1 standards */
+   if ((err = der_decode_sequence_multi(in, inlen, 
+                                  LTC_ASN1_INTEGER, 1UL, key->N, 
+                                  LTC_ASN1_EOL,     0UL, NULL)) != CRYPT_OK) {
+      goto LBL_ERR;
+   }
+
+   if (mp_cmp_d(key->N, 0) == LTC_MP_EQ) {
+      if ((err = mp_init(&zero)) != CRYPT_OK) { 
+         goto LBL_ERR;
+      }
+      /* it's a private key */
+      if ((err = der_decode_sequence_multi(in, inlen, 
+                          LTC_ASN1_INTEGER, 1UL, zero, 
+                          LTC_ASN1_INTEGER, 1UL, key->N, 
+                          LTC_ASN1_INTEGER, 1UL, key->e,
+                          LTC_ASN1_INTEGER, 1UL, key->d, 
+                          LTC_ASN1_INTEGER, 1UL, key->p, 
+                          LTC_ASN1_INTEGER, 1UL, key->q, 
+                          LTC_ASN1_INTEGER, 1UL, key->dP,
+                          LTC_ASN1_INTEGER, 1UL, key->dQ, 
+                          LTC_ASN1_INTEGER, 1UL, key->qP, 
+                          LTC_ASN1_EOL,     0UL, NULL)) != CRYPT_OK) {
+         mp_clear(zero);
+         goto LBL_ERR;
+      }
+      mp_clear(zero);
+      key->type = PK_PRIVATE;
+   } else if (mp_cmp_d(key->N, 1) == LTC_MP_EQ) {
+      /* we don't support multi-prime RSA */
+      err = CRYPT_PK_INVALID_TYPE;
+      goto LBL_ERR;
+   } else {
+      /* it's a public key and we lack e */
+      if ((err = der_decode_sequence_multi(in, inlen, 
+                                     LTC_ASN1_INTEGER, 1UL, key->N, 
+                                     LTC_ASN1_INTEGER, 1UL, key->e, 
+                                     LTC_ASN1_EOL,     0UL, NULL)) != CRYPT_OK) {
+         goto LBL_ERR;
+      }
+      key->type = PK_PUBLIC;
+   }
+   return CRYPT_OK;
+LBL_ERR:
+   mp_clear_multi(key->d,  key->e, key->N, key->dQ, key->dP, key->qP, key->p, key->q, NULL);
+   return err;
+}
+
+#endif /* MRSA */
+
+
+/* $Source: /cvs/libtom/libtomcrypt/src/pk/rsa/rsa_import.c,v $ */
+/* $Revision: 1.21 $ */
+/* $Date: 2006/12/04 22:23:27 $ */