always reject data >= n
[oweals/openssl.git] / crypto / rsa / rsa_eay.c
index e675d0a7b80fcb46ff4dac6baa5edf3ff3844431..cafdc419e26556bff814c2f48e6dacab0e74ea72 100644 (file)
 #include <openssl/bn.h>
 #include <openssl/rsa.h>
 #include <openssl/rand.h>
-#include <openssl/engine.h>
 
 #ifndef RSA_NULL
 
-static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
+static int RSA_eay_public_encrypt(int flen, unsigned char *from,
                unsigned char *to, RSA *rsa,int padding);
-static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
+static int RSA_eay_private_encrypt(int flen, unsigned char *from,
                unsigned char *to, RSA *rsa,int padding);
-static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
+static int RSA_eay_public_decrypt(int flen, unsigned char *from,
                unsigned char *to, RSA *rsa,int padding);
-static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
+static int RSA_eay_private_decrypt(int flen, unsigned char *from,
                unsigned char *to, RSA *rsa,int padding);
-static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa);
+static int RSA_eay_mod_exp(BIGNUM *r0, BIGNUM *i, RSA *rsa);
 static int RSA_eay_init(RSA *rsa);
 static int RSA_eay_finish(RSA *rsa);
 static RSA_METHOD rsa_pkcs1_eay_meth={
        "Eric Young's PKCS#1 RSA",
        RSA_eay_public_encrypt,
-       RSA_eay_public_decrypt,
-       RSA_eay_private_encrypt,
+       RSA_eay_public_decrypt, /* signature verification */
+       RSA_eay_private_encrypt, /* signing */
        RSA_eay_private_decrypt,
        RSA_eay_mod_exp,
        BN_mod_exp_mont,
@@ -90,21 +89,19 @@ static RSA_METHOD rsa_pkcs1_eay_meth={
        NULL,
        };
 
-const RSA_METHOD *RSA_PKCS1_SSLeay(void)
+RSA_METHOD *RSA_PKCS1_SSLeay(void)
        {
        return(&rsa_pkcs1_eay_meth);
        }
 
-static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
+static int RSA_eay_public_encrypt(int flen, unsigned char *from,
             unsigned char *to, RSA *rsa, int padding)
        {
-       const RSA_METHOD *meth;
        BIGNUM f,ret;
        int i,j,k,num=0,r= -1;
        unsigned char *buf=NULL;
        BN_CTX *ctx=NULL;
 
-       meth = ENGINE_get_RSA(rsa->engine);
        BN_init(&f);
        BN_init(&ret);
        if ((ctx=BN_CTX_new()) == NULL) goto err;
@@ -139,29 +136,38 @@ static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
 
        if (BN_bin2bn(buf,num,&f) == NULL) goto err;
        
+       if (BN_ucmp(&f, rsa->n) >= 0)
+               {       
+               /* usually the padding functions would catch this */
+               RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
+               goto err;
+               }
+
        if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
                {
-               CRYPTO_w_lock(CRYPTO_LOCK_RSA);
-               if (rsa->_method_mod_n == NULL)
+               BN_MONT_CTX* bn_mont_ctx;
+               if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
+                       goto err;
+               if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
                        {
-                       BN_MONT_CTX* bn_mont_ctx;
-                       if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
-                               {
-                               CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
-                               goto err;
-                               }
-                       if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
+                       BN_MONT_CTX_free(bn_mont_ctx);
+                       goto err;
+                       }
+               if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
+                       {
+                       CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+                       if (rsa->_method_mod_n == NULL)
                                {
-                               BN_MONT_CTX_free(bn_mont_ctx);
-                               CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
-                               goto err;
+                               rsa->_method_mod_n = bn_mont_ctx;
+                               bn_mont_ctx = NULL;
                                }
-                       rsa->_method_mod_n = bn_mont_ctx;
+                       CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
                        }
-               CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
+               if (bn_mont_ctx)
+                       BN_MONT_CTX_free(bn_mont_ctx);
                }
-
-       if (!meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
+               
+       if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
                rsa->_method_mod_n)) goto err;
 
        /* put in leading 0 bytes if the number is less than the
@@ -184,16 +190,15 @@ err:
        return(r);
        }
 
-static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
+/* signing */
+static int RSA_eay_private_encrypt(int flen, unsigned char *from,
             unsigned char *to, RSA *rsa, int padding)
        {
-       const RSA_METHOD *meth;
        BIGNUM f,ret;
        int i,j,k,num=0,r= -1;
        unsigned char *buf=NULL;
        BN_CTX *ctx=NULL;
 
-       meth = ENGINE_get_RSA(rsa->engine);
        BN_init(&f);
        BN_init(&ret);
 
@@ -221,6 +226,13 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
        if (i <= 0) goto err;
 
        if (BN_bin2bn(buf,num,&f) == NULL) goto err;
+       
+       if (BN_ucmp(&f, rsa->n) >= 0)
+               {       
+               /* usually the padding functions would catch this */
+               RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
+               goto err;
+               }
 
        if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
                RSA_blinding_on(rsa,ctx);
@@ -233,10 +245,10 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
                (rsa->dmp1 != NULL) &&
                (rsa->dmq1 != NULL) &&
                (rsa->iqmp != NULL)) )
-               { if (!meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
+               { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
        else
                {
-               if (!meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) goto err;
+               if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) goto err;
                }
 
        if (rsa->flags & RSA_FLAG_BLINDING)
@@ -262,17 +274,15 @@ err:
        return(r);
        }
 
-static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
+static int RSA_eay_private_decrypt(int flen, unsigned char *from,
             unsigned char *to, RSA *rsa, int padding)
        {
-       const RSA_METHOD *meth;
        BIGNUM f,ret;
        int j,num=0,r= -1;
        unsigned char *p;
        unsigned char *buf=NULL;
        BN_CTX *ctx=NULL;
 
-       meth = ENGINE_get_RSA(rsa->engine);
        BN_init(&f);
        BN_init(&ret);
        ctx=BN_CTX_new();
@@ -297,6 +307,12 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
        /* make data into a big number */
        if (BN_bin2bn(from,(int)flen,&f) == NULL) goto err;
 
+       if (BN_ucmp(&f, rsa->n) >= 0)
+               {
+               RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
+               goto err;
+               }
+
        if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
                RSA_blinding_on(rsa,ctx);
        if (rsa->flags & RSA_FLAG_BLINDING)
@@ -309,10 +325,10 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
                (rsa->dmp1 != NULL) &&
                (rsa->dmq1 != NULL) &&
                (rsa->iqmp != NULL)) )
-               { if (!meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
+               { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
        else
                {
-               if (!meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL))
+               if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL))
                        goto err;
                }
 
@@ -357,17 +373,16 @@ err:
        return(r);
        }
 
-static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
+/* signature verification */
+static int RSA_eay_public_decrypt(int flen, unsigned char *from,
             unsigned char *to, RSA *rsa, int padding)
        {
-       const RSA_METHOD *meth;
        BIGNUM f,ret;
        int i,num=0,r= -1;
        unsigned char *p;
        unsigned char *buf=NULL;
        BN_CTX *ctx=NULL;
 
-       meth = ENGINE_get_RSA(rsa->engine);
        BN_init(&f);
        BN_init(&ret);
        ctx=BN_CTX_new();
@@ -390,30 +405,39 @@ static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
                }
 
        if (BN_bin2bn(from,flen,&f) == NULL) goto err;
+
+       if (BN_ucmp(&f, rsa->n) >= 0)
+               {
+               RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
+               goto err;
+               }
+
        /* do the decrypt */
        if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
                {
-               CRYPTO_w_lock(CRYPTO_LOCK_RSA);
-               if (rsa->_method_mod_n == NULL)
+               BN_MONT_CTX* bn_mont_ctx;
+               if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
+                       goto err;
+               if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
                        {
-                       BN_MONT_CTX* bn_mont_ctx;
-                       if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
-                               {
-                               CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
-                               goto err;
-                               }
-                       if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
+                       BN_MONT_CTX_free(bn_mont_ctx);
+                       goto err;
+                       }
+               if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
+                       {
+                       CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+                       if (rsa->_method_mod_n == NULL)
                                {
-                               BN_MONT_CTX_free(bn_mont_ctx);
-                               CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
-                               goto err;
+                               rsa->_method_mod_n = bn_mont_ctx;
+                               bn_mont_ctx = NULL;
                                }
-                       rsa->_method_mod_n = bn_mont_ctx;
+                       CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
                        }
-               CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
+               if (bn_mont_ctx)
+                       BN_MONT_CTX_free(bn_mont_ctx);
                }
-
-       if (!meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
+               
+       if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
                rsa->_method_mod_n)) goto err;
 
        p=buf;
@@ -446,70 +470,74 @@ err:
        return(r);
        }
 
-static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
+static int RSA_eay_mod_exp(BIGNUM *r0, BIGNUM *I, RSA *rsa)
        {
-       const RSA_METHOD *meth;
-       BIGNUM r1,m1;
+       BIGNUM r1,m1,vrfy;
        int ret=0;
        BN_CTX *ctx;
 
-       meth = ENGINE_get_RSA(rsa->engine);
        if ((ctx=BN_CTX_new()) == NULL) goto err;
        BN_init(&m1);
        BN_init(&r1);
+       BN_init(&vrfy);
 
        if (rsa->flags & RSA_FLAG_CACHE_PRIVATE)
                {
                if (rsa->_method_mod_p == NULL)
                        {
-                       CRYPTO_w_lock(CRYPTO_LOCK_RSA);
-                       if (rsa->_method_mod_p == NULL)
+                       BN_MONT_CTX* bn_mont_ctx;
+                       if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
+                               goto err;
+                       if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->p,ctx))
                                {
-                               BN_MONT_CTX* bn_mont_ctx;
-                               if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
-                                       {
-                                       CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
-                                       goto err;
-                                       }
-                               if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->p,ctx))
+                               BN_MONT_CTX_free(bn_mont_ctx);
+                               goto err;
+                               }
+                       if (rsa->_method_mod_p == NULL) /* other thread may have finished first */
+                               {
+                               CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+                               if (rsa->_method_mod_p == NULL)
                                        {
-                                       BN_MONT_CTX_free(bn_mont_ctx);
-                                       CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
-                                       goto err;
+                                       rsa->_method_mod_p = bn_mont_ctx;
+                                       bn_mont_ctx = NULL;
                                        }
-                               rsa->_method_mod_p = bn_mont_ctx;
-                               }
                                CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
+                               }
+                       if (bn_mont_ctx)
+                               BN_MONT_CTX_free(bn_mont_ctx);
                        }
+
                if (rsa->_method_mod_q == NULL)
                        {
-                       CRYPTO_w_lock(CRYPTO_LOCK_RSA);
-                       if (rsa->_method_mod_q == NULL)
+                       BN_MONT_CTX* bn_mont_ctx;
+                       if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
+                               goto err;
+                       if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->q,ctx))
                                {
-                               BN_MONT_CTX* bn_mont_ctx;
-                               if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
-                                       {
-                                       CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
-                                       goto err;
-                                       }
-                               if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->q,ctx))
+                               BN_MONT_CTX_free(bn_mont_ctx);
+                               goto err;
+                               }
+                       if (rsa->_method_mod_q == NULL) /* other thread may have finished first */
+                               {
+                               CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+                               if (rsa->_method_mod_q == NULL)
                                        {
-                                       BN_MONT_CTX_free(bn_mont_ctx);
-                                       CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
-                                       goto err;
+                                       rsa->_method_mod_q = bn_mont_ctx;
+                                       bn_mont_ctx = NULL;
                                        }
-                               rsa->_method_mod_q = bn_mont_ctx;
+                               CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
                                }
-                       CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
+                       if (bn_mont_ctx)
+                               BN_MONT_CTX_free(bn_mont_ctx);
                        }
                }
-
+               
        if (!BN_mod(&r1,I,rsa->q,ctx)) goto err;
-       if (!meth->bn_mod_exp(&m1,&r1,rsa->dmq1,rsa->q,ctx,
+       if (!rsa->meth->bn_mod_exp(&m1,&r1,rsa->dmq1,rsa->q,ctx,
                rsa->_method_mod_q)) goto err;
 
        if (!BN_mod(&r1,I,rsa->p,ctx)) goto err;
-       if (!meth->bn_mod_exp(r0,&r1,rsa->dmp1,rsa->p,ctx,
+       if (!rsa->meth->bn_mod_exp(r0,&r1,rsa->dmp1,rsa->p,ctx,
                rsa->_method_mod_p)) goto err;
 
        if (!BN_sub(r0,r0,&m1)) goto err;
@@ -532,10 +560,19 @@ static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
        if (!BN_mul(&r1,r0,rsa->q,ctx)) goto err;
        if (!BN_add(r0,&r1,&m1)) goto err;
 
+       if (rsa->e && rsa->n)
+               {
+               if (!rsa->meth->bn_mod_exp(&vrfy,r0,rsa->e,rsa->n,ctx,NULL)) goto err;
+               if (BN_cmp(I, &vrfy) != 0)
+                       {
+                       if (!rsa->meth->bn_mod_exp(r0,I,rsa->d,rsa->n,ctx,NULL)) goto err;
+                       }
+               }
        ret=1;
 err:
        BN_clear_free(&m1);
        BN_clear_free(&r1);
+       BN_clear_free(&vrfy);
        BN_CTX_free(ctx);
        return(ret);
        }