From: Dr. Stephen Henson Date: Sun, 28 Mar 2004 17:38:00 +0000 (+0000) Subject: Enhance EVP code to generate random symmetric keys of the X-Git-Tag: OpenSSL_0_9_7e~130^2~7 X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff_plain;h=216659eb87485402a8e861a6de77233d1f5d7425 Enhance EVP code to generate random symmetric keys of the appropriate form, for example correct DES parity. Update S/MIME code and EVP_SealInit to use new functions. PR: 700 --- diff --git a/CHANGES b/CHANGES index c5c2ebba9b..a72d5d6eaa 100644 --- a/CHANGES +++ b/CHANGES @@ -4,6 +4,16 @@ Changes between 0.9.7c and 0.9.8 [xx XXX xxxx] + *) Add new EVP function EVP_CIPHER_CTX_rand_key and associated functionality. + This will generate a random key of the appropriate length based on the + cipher context. The EVP_CIPHER can provide its own random key generation + routine to support keys of a specific form. This is used in the des and + 3des routines to generate a key of the correct parity. Update S/MIME + code to use new functions and hence generate correct parity DES keys. + Add EVP_CHECK_DES_KEY #define to return an error if the key is not + valid (weak or incorrect parity). + [Steve Henson] + *) Add a local set of CRLs that can be used by X509_verify_cert() as well as looking them up. This is useful when the verified structure may contain CRLs, for example PKCS#7 signedData. Modify PKCS7_verify() to use any CRLs diff --git a/crypto/evp/e_des.c b/crypto/evp/e_des.c index f2554ecc6a..856323648c 100644 --- a/crypto/evp/e_des.c +++ b/crypto/evp/e_des.c @@ -63,9 +63,11 @@ #include #include "evp_locl.h" #include +#include static int des_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key, const unsigned char *iv, int enc); +static int des_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr); /* Because of various casts and different names can't use IMPLEMENT_BLOCK_CIPHER */ @@ -127,26 +129,48 @@ static int des_cfb8_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, } BLOCK_CIPHER_defs(des, DES_key_schedule, NID_des, 8, 8, 8, 64, - 0, des_init_key, NULL, + EVP_CIPH_RAND_KEY, des_init_key, NULL, EVP_CIPHER_set_asn1_iv, EVP_CIPHER_get_asn1_iv, - NULL) + des_ctrl) -BLOCK_CIPHER_def_cfb(des,DES_key_schedule,NID_des,8,8,1,0,des_init_key,NULL, +BLOCK_CIPHER_def_cfb(des,DES_key_schedule,NID_des,8,8,1, + EVP_CIPH_RAND_KEY, des_init_key,NULL, EVP_CIPHER_set_asn1_iv, - EVP_CIPHER_get_asn1_iv,NULL) + EVP_CIPHER_get_asn1_iv,des_ctrl) -BLOCK_CIPHER_def_cfb(des,DES_key_schedule,NID_des,8,8,8,0,des_init_key,NULL, +BLOCK_CIPHER_def_cfb(des,DES_key_schedule,NID_des,8,8,8, + EVP_CIPH_RAND_KEY,des_init_key,NULL, EVP_CIPHER_set_asn1_iv, - EVP_CIPHER_get_asn1_iv,NULL) + EVP_CIPHER_get_asn1_iv,des_ctrl) static int des_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key, const unsigned char *iv, int enc) { DES_cblock *deskey = (DES_cblock *)key; - +#ifdef EVP_CHECK_DES_KEY + if(DES_set_key_checked(deskey,ctx->cipher_data) != 0) + return 0; +#else DES_set_key_unchecked(deskey,ctx->cipher_data); +#endif return 1; } +static int des_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr) + { + + switch(type) + { + case EVP_CTRL_RAND_KEY: + if (RAND_bytes(ptr, 8) <= 0) + return 0; + DES_set_odd_parity((DES_cblock *)ptr); + return 1; + + default: + return -1; + } + } + #endif diff --git a/crypto/evp/e_des3.c b/crypto/evp/e_des3.c index 86342fb952..ac148efab2 100644 --- a/crypto/evp/e_des3.c +++ b/crypto/evp/e_des3.c @@ -63,6 +63,7 @@ #include #include "evp_locl.h" #include +#include static int des_ede_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key, const unsigned char *iv,int enc); @@ -70,6 +71,8 @@ static int des_ede_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key, static int des_ede3_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key, const unsigned char *iv,int enc); +static int des3_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr); + typedef struct { DES_key_schedule ks1;/* key schedule */ @@ -161,10 +164,10 @@ static int des_ede3_cfb8_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, } BLOCK_CIPHER_defs(des_ede, DES_EDE_KEY, NID_des_ede, 8, 16, 8, 64, - 0, des_ede_init_key, NULL, + EVP_CIPH_RAND_KEY, des_ede_init_key, NULL, EVP_CIPHER_set_asn1_iv, EVP_CIPHER_get_asn1_iv, - NULL) + des3_ctrl) #define des_ede3_cfb64_cipher des_ede_cfb64_cipher #define des_ede3_ofb_cipher des_ede_ofb_cipher @@ -172,28 +175,35 @@ BLOCK_CIPHER_defs(des_ede, DES_EDE_KEY, NID_des_ede, 8, 16, 8, 64, #define des_ede3_ecb_cipher des_ede_ecb_cipher BLOCK_CIPHER_defs(des_ede3, DES_EDE_KEY, NID_des_ede3, 8, 24, 8, 64, - 0, des_ede3_init_key, NULL, + EVP_CIPH_RAND_KEY, des_ede3_init_key, NULL, EVP_CIPHER_set_asn1_iv, EVP_CIPHER_get_asn1_iv, - NULL) + des3_ctrl) -BLOCK_CIPHER_def_cfb(des_ede3,DES_EDE_KEY,NID_des_ede3,24,8,1,0, - des_ede3_init_key,NULL, +BLOCK_CIPHER_def_cfb(des_ede3,DES_EDE_KEY,NID_des_ede3,24,8,1, + EVP_CIPH_RAND_KEY, des_ede3_init_key,NULL, EVP_CIPHER_set_asn1_iv, - EVP_CIPHER_get_asn1_iv,NULL) + EVP_CIPHER_get_asn1_iv, + des3_ctrl) -BLOCK_CIPHER_def_cfb(des_ede3,DES_EDE_KEY,NID_des_ede3,24,8,8,0, - des_ede3_init_key,NULL, +BLOCK_CIPHER_def_cfb(des_ede3,DES_EDE_KEY,NID_des_ede3,24,8,8, + EVP_CIPH_RAND_KEY, des_ede3_init_key,NULL, EVP_CIPHER_set_asn1_iv, - EVP_CIPHER_get_asn1_iv,NULL) + EVP_CIPHER_get_asn1_iv, + des3_ctrl) static int des_ede_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key, const unsigned char *iv, int enc) { DES_cblock *deskey = (DES_cblock *)key; - +#ifdef EVP_CHECK_DES_KEY + if (DES_set_key_checked(&deskey[0],&data(ctx)->ks1) + !! DES_set_key_checked(&deskey[1],&data(ctx)->ks2)) + return 0; +#else DES_set_key_unchecked(&deskey[0],&data(ctx)->ks1); DES_set_key_unchecked(&deskey[1],&data(ctx)->ks2); +#endif memcpy(&data(ctx)->ks3,&data(ctx)->ks1, sizeof(data(ctx)->ks1)); return 1; @@ -214,13 +224,41 @@ static int des_ede3_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key, } #endif /* KSSL_DEBUG */ +#ifdef EVP_CHECK_DES_KEY + if (DES_set_key_checked(&deskey[0],&data(ctx)->ks1) + || DES_set_key_checked(&deskey[1],&data(ctx)->ks2) + || DES_set_key_checked(&deskey[2],&data(ctx)->ks3)) + return 0; +#else DES_set_key_unchecked(&deskey[0],&data(ctx)->ks1); DES_set_key_unchecked(&deskey[1],&data(ctx)->ks2); DES_set_key_unchecked(&deskey[2],&data(ctx)->ks3); - +#endif return 1; } +static int des3_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr) + { + + DES_cblock *deskey = ptr; + + switch(type) + { + case EVP_CTRL_RAND_KEY: + if (RAND_bytes(ptr, c->key_len) <= 0) + return 0; + DES_set_odd_parity(deskey); + if (c->key_len >= 16) + DES_set_odd_parity(deskey + 1); + if (c->key_len >= 24) + DES_set_odd_parity(deskey + 2); + return 1; + + default: + return -1; + } + } + const EVP_CIPHER *EVP_des_ede(void) { return &des_ede_ecb; diff --git a/crypto/evp/evp.h b/crypto/evp/evp.h index ce5c210f61..6adbe891a0 100644 --- a/crypto/evp/evp.h +++ b/crypto/evp/evp.h @@ -332,6 +332,8 @@ struct evp_cipher_st #define EVP_CIPH_CUSTOM_KEY_LENGTH 0x80 /* Don't use standard block padding */ #define EVP_CIPH_NO_PADDING 0x100 +/* cipher handles random key generation */ +#define EVP_CIPH_RAND_KEY 0x200 /* ctrl() values */ @@ -341,6 +343,7 @@ struct evp_cipher_st #define EVP_CTRL_SET_RC2_KEY_BITS 0x3 #define EVP_CTRL_GET_RC5_ROUNDS 0x4 #define EVP_CTRL_SET_RC5_ROUNDS 0x5 +#define EVP_CTRL_RAND_KEY 0x6 typedef struct evp_cipher_info_st { @@ -567,6 +570,7 @@ int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *a); int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *x, int keylen); int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *c, int pad); int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr); +int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key); #ifndef OPENSSL_NO_BIO BIO_METHOD *BIO_f_md(void); diff --git a/crypto/evp/evp_enc.c b/crypto/evp/evp_enc.c index cecb09cbe7..b5236b9766 100644 --- a/crypto/evp/evp_enc.c +++ b/crypto/evp/evp_enc.c @@ -534,3 +534,13 @@ int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr) } return ret; } + +int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key) + { + if (ctx->cipher->flags & EVP_CIPH_RAND_KEY) + return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key); + if (RAND_bytes(key, ctx->key_len) <= 0) + return 0; + return 1; + } + diff --git a/crypto/evp/p_seal.c b/crypto/evp/p_seal.c index 37e547fe72..8cc8fcb0bd 100644 --- a/crypto/evp/p_seal.c +++ b/crypto/evp/p_seal.c @@ -78,7 +78,7 @@ int EVP_SealInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type, unsigned char **ek } if ((npubk <= 0) || !pubk) return 1; - if (RAND_bytes(key,EVP_MAX_KEY_LENGTH) <= 0) + if (EVP_CIPHER_CTX_rand_key(ctx, key) <= 0) return 0; if (EVP_CIPHER_CTX_iv_length(ctx)) RAND_pseudo_bytes(iv,EVP_CIPHER_CTX_iv_length(ctx)); diff --git a/crypto/pkcs7/pk7_doit.c b/crypto/pkcs7/pk7_doit.c index 0b262fa065..25483bc156 100644 --- a/crypto/pkcs7/pk7_doit.c +++ b/crypto/pkcs7/pk7_doit.c @@ -215,11 +215,14 @@ BIO *PKCS7_dataInit(PKCS7 *p7, BIO *bio) BIO_get_cipher_ctx(btmp, &ctx); keylen=EVP_CIPHER_key_length(evp_cipher); ivlen=EVP_CIPHER_iv_length(evp_cipher); - if (RAND_bytes(key,keylen) <= 0) - goto err; xalg->algorithm = OBJ_nid2obj(EVP_CIPHER_type(evp_cipher)); if (ivlen > 0) RAND_pseudo_bytes(iv,ivlen); - EVP_CipherInit_ex(ctx, evp_cipher, NULL, key, iv, 1); + if (EVP_CipherInit_ex(ctx, evp_cipher, NULL, NULL, NULL, 1)<=0) + goto err; + if (EVP_CIPHER_CTX_rand_key(ctx, key) <= 0) + goto err; + if (EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, 1) <= 0) + goto err; if (ivlen > 0) { if (xalg->parameter == NULL) @@ -440,7 +443,8 @@ BIO *PKCS7_dataDecode(PKCS7 *p7, EVP_PKEY *pkey, BIO *in_bio, X509 *pcert) evp_ctx=NULL; BIO_get_cipher_ctx(etmp,&evp_ctx); - EVP_CipherInit_ex(evp_ctx,evp_cipher,NULL,NULL,NULL,0); + if (EVP_CipherInit_ex(evp_ctx,evp_cipher,NULL,NULL,NULL,0) <= 0) + goto err; if (EVP_CIPHER_asn1_to_param(evp_ctx,enc_alg->parameter) < 0) goto err; @@ -456,7 +460,8 @@ BIO *PKCS7_dataDecode(PKCS7 *p7, EVP_PKEY *pkey, BIO *in_bio, X509 *pcert) goto err; } } - EVP_CipherInit_ex(evp_ctx,NULL,NULL,tmp,NULL,0); + if (EVP_CipherInit_ex(evp_ctx,NULL,NULL,tmp,NULL,0) <= 0) + goto err; OPENSSL_cleanse(tmp,jj);