FIPS mode RSA changes:
[openssl.git] / crypto / rsa / rsa_gen.c
index aed2351cfbfdd94689267254713cc2a325a88703..b8676ad020dc6303dca33ae52aef5d8382c56daf 100644 (file)
  * [including the GNU Public Licence.]
  */
 
+
+/* NB: these functions have been "upgraded", the deprecated versions (which are
+ * compatibility wrappers using these functions) are in rsa_depr.c.
+ * - Geoff
+ */
+
 #include <stdio.h>
 #include <time.h>
 #include "cryptlib.h"
-#include "bn.h"
-#include "rsa.h"
-
-RSA *RSA_generate_key(bits, e_value, callback,cb_arg)
-int bits;
-unsigned long e_value;
-void (*callback)(P_I_I_P);
-char *cb_arg;
+#include <openssl/bn.h>
+#include <openssl/rsa.h>
+
+#ifdef OPENSSL_FIPS
+
+#include <openssl/fips.h>
+#include <openssl/evp.h>
+
+static int fips_rsa_pairwise_fail = 0;
+
+void FIPS_corrupt_rsa_keygen(void)
+       {
+       fips_rsa_pairwise_fail = 1;
+       }
+
+int fips_check_rsa(RSA *rsa)
+       {
+       const unsigned char tbs[] = "RSA Pairwise Check Data";
+       unsigned char *ctbuf = NULL, *ptbuf = NULL;
+       int len, ret = 0;
+       EVP_PKEY pk;
+       pk.type = EVP_PKEY_RSA;
+       pk.pkey.rsa = rsa;
+
+       /* Perform pairwise consistency signature test */
+       if (!fips_pkey_signature_test(&pk, tbs, -1,
+                       NULL, 0, EVP_sha1(), RSA_PKCS1_PADDING, NULL)
+               || !fips_pkey_signature_test(&pk, tbs, -1,
+                       NULL, 0, EVP_sha1(), RSA_X931_PADDING, NULL)
+               || !fips_pkey_signature_test(&pk, tbs, -1,
+                       NULL, 0, EVP_sha1(), RSA_PKCS1_PSS_PADDING, NULL))
+               goto err;
+       /* Now perform pairwise consistency encrypt/decrypt test */
+       ctbuf = OPENSSL_malloc(RSA_size(rsa));
+       if (!ctbuf)
+               goto err;
+
+       len = RSA_public_encrypt(sizeof(tbs) - 1, tbs, ctbuf, rsa, RSA_PKCS1_PADDING);
+       if (len <= 0)
+               goto err;
+       /* Check ciphertext doesn't match plaintext */
+       if ((len == (sizeof(tbs) - 1)) && !memcmp(tbs, ctbuf, len))
+               goto err;
+       ptbuf = OPENSSL_malloc(RSA_size(rsa));
+
+       if (!ptbuf)
+               goto err;
+       len = RSA_private_decrypt(len, ctbuf, ptbuf, rsa, RSA_PKCS1_PADDING);
+       if (len != (sizeof(tbs) - 1))
+               goto err;
+       if (memcmp(ptbuf, tbs, len))
+               goto err;
+
+       ret = 1;
+
+       if (!ptbuf)
+               goto err;
+       
+       err:
+       if (ret == 0)
+               {
+               fips_set_selftest_fail();
+               FIPSerr(FIPS_F_FIPS_CHECK_RSA,FIPS_R_PAIRWISE_TEST_FAILED);
+               }
+
+       if (ctbuf)
+               OPENSSL_free(ctbuf);
+       if (ptbuf)
+               OPENSSL_free(ptbuf);
+
+       return ret;
+       }
+#endif
+
+static int rsa_builtin_keygen(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb);
+
+/* NB: this wrapper would normally be placed in rsa_lib.c and the static
+ * implementation would probably be in rsa_eay.c. Nonetheless, is kept here so
+ * that we don't introduce a new linker dependency. Eg. any application that
+ * wasn't previously linking object code related to key-generation won't have to
+ * now just because key-generation is part of RSA_METHOD. */
+int RSA_generate_key_ex(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb)
+       {
+       if(rsa->meth->rsa_keygen)
+               return rsa->meth->rsa_keygen(rsa, bits, e_value, cb);
+       return rsa_builtin_keygen(rsa, bits, e_value, cb);
+       }
+
+static int rsa_builtin_keygen(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb)
        {
-       RSA *rsa=NULL;
        BIGNUM *r0=NULL,*r1=NULL,*r2=NULL,*r3=NULL,*tmp;
+       BIGNUM local_r0,local_d,local_p;
+       BIGNUM *pr0,*d,*p;
        int bitsp,bitsq,ok= -1,n=0;
-       BN_CTX *ctx=NULL,*ctx2=NULL;
+       BN_CTX *ctx=NULL;
+
+#ifdef OPENSSL_FIPS
+       if(FIPS_selftest_failed())
+           {
+           FIPSerr(FIPS_F_RSA_BUILTIN_KEYGEN,FIPS_R_FIPS_SELFTEST_FAILED);
+           return 0;
+           }
+
+       if (FIPS_mode() && (bits < OPENSSL_RSA_FIPS_MIN_MODULUS_BITS))
+           {
+           FIPSerr(FIPS_F_RSA_BUILTIN_KEYGEN,FIPS_R_KEY_TOO_SHORT);
+           return 0;
+           }
+#endif
 
        ctx=BN_CTX_new();
        if (ctx == NULL) goto err;
-       ctx2=BN_CTX_new();
-       if (ctx2 == NULL) goto err;
-       r0=ctx->bn[0];
-       r1=ctx->bn[1];
-       r2=ctx->bn[2];
-       r3=ctx->bn[3];
-       ctx->tos+=4;
+       BN_CTX_start(ctx);
+       r0 = BN_CTX_get(ctx);
+       r1 = BN_CTX_get(ctx);
+       r2 = BN_CTX_get(ctx);
+       r3 = BN_CTX_get(ctx);
+       if (r3 == NULL) goto err;
 
        bitsp=(bits+1)/2;
        bitsq=bits-bitsp;
-       rsa=RSA_new();
-       if (rsa == NULL) goto err;
 
-       /* set e */ 
-       rsa->e=BN_new();
-       if (rsa->e == NULL) goto err;
-       if (!BN_set_word(rsa->e,e_value)) goto err;
+       /* We need the RSA components non-NULL */
+       if(!rsa->n && ((rsa->n=BN_new()) == NULL)) goto err;
+       if(!rsa->d && ((rsa->d=BN_new()) == NULL)) goto err;
+       if(!rsa->e && ((rsa->e=BN_new()) == NULL)) goto err;
+       if(!rsa->p && ((rsa->p=BN_new()) == NULL)) goto err;
+       if(!rsa->q && ((rsa->q=BN_new()) == NULL)) goto err;
+       if(!rsa->dmp1 && ((rsa->dmp1=BN_new()) == NULL)) goto err;
+       if(!rsa->dmq1 && ((rsa->dmq1=BN_new()) == NULL)) goto err;
+       if(!rsa->iqmp && ((rsa->iqmp=BN_new()) == NULL)) goto err;
+
+       BN_copy(rsa->e, e_value);
 
        /* generate p and q */
        for (;;)
                {
-               rsa->p=BN_generate_prime(bitsp,0,NULL,NULL,callback,cb_arg);
-               if (rsa->p == NULL) goto err;
+               if(!BN_generate_prime_ex(rsa->p, bitsp, 0, NULL, NULL, cb))
+                       goto err;
                if (!BN_sub(r2,rsa->p,BN_value_one())) goto err;
                if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
                if (BN_is_one(r1)) break;
-               if (callback != NULL) callback(2,n++,cb_arg);
-               BN_free(rsa->p);
+               if(!BN_GENCB_call(cb, 2, n++))
+                       goto err;
                }
-       if (callback != NULL) callback(3,0,cb_arg);
+       if(!BN_GENCB_call(cb, 3, 0))
+               goto err;
        for (;;)
                {
-               rsa->q=BN_generate_prime(bitsq,0,NULL,NULL,callback,cb_arg);
-               if (rsa->q == NULL) goto err;
+               /* When generating ridiculously small keys, we can get stuck
+                * continually regenerating the same prime values. Check for
+                * this and bail if it happens 3 times. */
+               unsigned int degenerate = 0;
+               do
+                       {
+                       if(!BN_generate_prime_ex(rsa->q, bitsq, 0, NULL, NULL, cb))
+                               goto err;
+                       } while((BN_cmp(rsa->p, rsa->q) == 0) && (++degenerate < 3));
+               if(degenerate == 3)
+                       {
+                       ok = 0; /* we set our own err */
+                       RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,RSA_R_KEY_SIZE_TOO_SMALL);
+                       goto err;
+                       }
                if (!BN_sub(r2,rsa->q,BN_value_one())) goto err;
                if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
-               if (BN_is_one(r1) && (BN_cmp(rsa->p,rsa->q) != 0))
+               if (BN_is_one(r1))
                        break;
-               if (callback != NULL) callback(2,n++,cb_arg);
-               BN_free(rsa->q);
+               if(!BN_GENCB_call(cb, 2, n++))
+                       goto err;
                }
-       if (callback != NULL) callback(3,1,cb_arg);
+       if(!BN_GENCB_call(cb, 3, 1))
+               goto err;
        if (BN_cmp(rsa->p,rsa->q) < 0)
                {
                tmp=rsa->p;
@@ -125,63 +246,67 @@ char *cb_arg;
                }
 
        /* calculate n */
-       rsa->n=BN_new();
-       if (rsa->n == NULL) goto err;
-       if (!BN_mul(rsa->n,rsa->p,rsa->q)) goto err;
+       if (!BN_mul(rsa->n,rsa->p,rsa->q,ctx)) goto err;
 
        /* calculate d */
        if (!BN_sub(r1,rsa->p,BN_value_one())) goto err;        /* p-1 */
        if (!BN_sub(r2,rsa->q,BN_value_one())) goto err;        /* q-1 */
-       if (!BN_mul(r0,r1,r2)) goto err;        /* (p-1)(q-1) */
-
-/* should not be needed, since gcd(p-1,e) == 1 and gcd(q-1,e) == 1 */
-/*     for (;;)
+       if (!BN_mul(r0,r1,r2,ctx)) goto err;    /* (p-1)(q-1) */
+       if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
                {
-               if (!BN_gcd(r3,r0,rsa->e,ctx)) goto err;
-               if (BN_is_one(r3)) break;
+                 pr0 = &local_r0;
+                 BN_with_flags(pr0, r0, BN_FLG_CONSTTIME);
+               }
+       else
+         pr0 = r0;
+       if (!BN_mod_inverse(rsa->d,rsa->e,pr0,ctx)) goto err;   /* d */
 
-               if (1)
-                       {
-                       if (!BN_add_word(rsa->e,2L)) goto err;
-                       continue;
-                       }
-               RSAerr(RSA_F_RSA_GENERATE_KEY,RSA_R_BAD_E_VALUE);
-               goto err;
+       /* set up d for correct BN_FLG_CONSTTIME flag */
+       if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
+               {
+               d = &local_d;
+               BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
                }
-*/
-       rsa->d=(BIGNUM *)BN_mod_inverse(rsa->e,r0,ctx2);        /* d */
-       if (rsa->d == NULL) goto err;
+       else
+               d = rsa->d;
 
        /* calculate d mod (p-1) */
-       rsa->dmp1=BN_new();
-       if (rsa->dmp1 == NULL) goto err;
-       if (!BN_mod(rsa->dmp1,rsa->d,r1,ctx)) goto err;
+       if (!BN_mod(rsa->dmp1,d,r1,ctx)) goto err;
 
        /* calculate d mod (q-1) */
-       rsa->dmq1=BN_new();
-       if (rsa->dmq1 == NULL) goto err;
-       if (!BN_mod(rsa->dmq1,rsa->d,r2,ctx)) goto err;
+       if (!BN_mod(rsa->dmq1,d,r2,ctx)) goto err;
 
        /* calculate inverse of q mod p */
-       rsa->iqmp=BN_mod_inverse(rsa->q,rsa->p,ctx2);
-       if (rsa->iqmp == NULL) goto err;
+       if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
+               {
+               p = &local_p;
+               BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
+               }
+       else
+               p = rsa->p;
+       if (!BN_mod_inverse(rsa->iqmp,rsa->q,p,ctx)) goto err;
+
+#ifdef OPENSSL_FIPS
+       if (fips_rsa_pairwise_fail)
+               BN_add_word(rsa->n, 1);
+
+       if(!fips_check_rsa(rsa))
+           goto err;
+#endif
 
        ok=1;
 err:
        if (ok == -1)
                {
-               RSAerr(RSA_F_RSA_GENERATE_KEY,ERR_LIB_BN);
+               RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,ERR_LIB_BN);
                ok=0;
                }
-       BN_CTX_free(ctx);
-       BN_CTX_free(ctx2);
-       
-       if (!ok)
+       if (ctx != NULL)
                {
-               if (rsa != NULL) RSA_free(rsa);
-               return(NULL);
+               BN_CTX_end(ctx);
+               BN_CTX_free(ctx);
                }
-       else
-               return(rsa);
+
+       return ok;
        }