SSL_CIPHER lookup functions.

Add tables to convert between SSL_CIPHER fields and indices for ciphers
and MACs.

Reorganise ssl_ciph.c to use tables to lookup values and load them.

New functions SSL_CIPHER_get_cipher_nid and SSL_CIPHER_get_digest_nid.

Add documentation.

Reviewed-by: Rich Salz <rsalz@openssl.org>
This commit is contained in:
Dr. Stephen Henson 2015-04-21 15:48:02 +01:00
parent b95de5ecde
commit 98c9ce2f55
3 changed files with 107 additions and 125 deletions

View File

@ -12,6 +12,8 @@ SSL_CIPHER_get_name, SSL_CIPHER_get_bits, SSL_CIPHER_get_version, SSL_CIPHER_des
int SSL_CIPHER_get_bits(const SSL_CIPHER *cipher, int *alg_bits);
char *SSL_CIPHER_get_version(const SSL_CIPHER *cipher);
char *SSL_CIPHER_description(const SSL_CIPHER *cipher, char *buf, int size);
int SSL_CIPHER_get_cipher_nid(const SSL_CIPHER *c);
int SSL_CIPHER_get_digest_nid(const SSL_CIPHER *c);
=head1 DESCRIPTION
@ -37,6 +39,14 @@ returned. If B<buf> is NULL, a buffer of 128 bytes is allocated using
OPENSSL_malloc(). If the allocation fails, a pointer to the string
"OPENSSL_malloc Error" is returned.
SSL_CIPHER_get_cipher_nid() returns the cipher NID corresponding to B<c>.
If there is no cipher (e.g. for ciphersuites with no encryption) then
B<NID_undef> is returned.
SSL_CIPHER_get_digest_nid() returns the digest NID corresponding to the MAC
used by B<c>. If there is no digest (e.g. for AEAD ciphersuites) then
B<NID_undef> is returned.
=head1 NOTES
The number of bits processed can be different from the secret bits. An

View File

@ -1789,6 +1789,8 @@ __owur int SSL_COMP_add_compression_method(int id, void *cm);
# endif
const SSL_CIPHER *SSL_CIPHER_find(SSL *ssl, const unsigned char *ptr);
int SSL_CIPHER_get_cipher_nid(const SSL_CIPHER *c);
int SSL_CIPHER_get_digest_nid(const SSL_CIPHER *c);
/* TLS extensions functions */
__owur int SSL_set_session_ticket_ext(SSL *s, void *ext_data, int ext_len);

View File

@ -166,6 +166,31 @@
#define SSL_ENC_AES256GCM_IDX 13
#define SSL_ENC_NUM_IDX 14
/* NB: make sure indices in these tables match values above */
typedef struct {
unsigned long mask;
int nid;
} ssl_cipher_table;
/* Table of NIDs for each cipher */
static const ssl_cipher_table ssl_cipher_table_cipher[SSL_ENC_NUM_IDX] = {
{SSL_DES, NID_des_cbc}, /* SSL_ENC_DES_IDX 0 */
{SSL_3DES, NID_des_ede3_cbc}, /* SSL_ENC_3DES_IDX 1 */
{SSL_RC4, NID_rc4}, /* SSL_ENC_RC4_IDX 2 */
{SSL_RC2, NID_rc2_cbc}, /* SSL_ENC_RC2_IDX 3 */
{SSL_IDEA, NID_idea_cbc}, /* SSL_ENC_IDEA_IDX 4 */
{SSL_eNULL, NID_undef}, /* SSL_ENC_NULL_IDX 5 */
{SSL_AES128, NID_aes_128_cbc}, /* SSL_ENC_AES128_IDX 6 */
{SSL_AES256, NID_aes_256_cbc}, /* SSL_ENC_AES256_IDX 7 */
{SSL_CAMELLIA128, NID_camellia_128_cbc}, /* SSL_ENC_CAMELLIA128_IDX 8 */
{SSL_CAMELLIA256, NID_camellia_256_cbc}, /* SSL_ENC_CAMELLIA256_IDX 9 */
{SSL_eGOST2814789CNT, NID_gost89_cnt}, /* SSL_ENC_GOST89_IDX 10 */
{SSL_SEED, NID_seed_cbc}, /* SSL_ENC_SEED_IDX 11 */
{SSL_AES128GCM, NID_aes_128_gcm}, /* SSL_ENC_AES128GCM_IDX 12 */
{SSL_AES256GCM, NID_aes_256_gcm} /* SSL_ENC_AES256GCM_IDX 13 */
};
static const EVP_CIPHER *ssl_cipher_methods[SSL_ENC_NUM_IDX] = {
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL
@ -187,11 +212,38 @@ static STACK_OF(SSL_COMP) *ssl_comp_methods = NULL;
* Constant SSL_MAX_DIGEST equal to size of digests array should be defined
* in the ssl_locl.h
*/
#define SSL_MD_NUM_IDX SSL_MAX_DIGEST
/* NB: make sure indices in this table matches values above */
static const ssl_cipher_table ssl_cipher_table_mac[SSL_MD_NUM_IDX] = {
{SSL_MD5, NID_md5}, /* SSL_MD_MD5_IDX 0 */
{SSL_SHA1, NID_sha1}, /* SSL_MD_SHA1_IDX 1 */
{SSL_GOST94, NID_id_GostR3411_94}, /* SSL_MD_GOST94_IDX 2 */
{SSL_GOST89MAC, NID_id_Gost28147_89_MAC}, /* SSL_MD_GOST89MAC_IDX 3 */
{SSL_SHA256, NID_sha256}, /* SSL_MD_SHA256_IDX 4 */
{SSL_SHA384, NID_sha384} /* SSL_MD_SHA384_IDX 5 */
};
static const EVP_MD *ssl_digest_methods[SSL_MD_NUM_IDX] = {
NULL, NULL, NULL, NULL, NULL, NULL
};
/* Utility function for table lookup */
static int ssl_cipher_info_find(const ssl_cipher_table * table,
size_t table_cnt, unsigned long mask)
{
size_t i;
for (i = 0; i < table_cnt; i++, table++) {
if (table->mask == mask)
return i;
}
return -1;
}
#define ssl_cipher_info_lookup(table, x) \
ssl_cipher_info_find(table, sizeof(table)/sizeof(*table), x)
/*
* PKEY_TYPE for GOST89MAC is known in advance, but, because implementation
* is engine-provided, we'll fill it only if corresponding EVP_PKEY_METHOD is
@ -403,61 +455,25 @@ static int get_optional_pkey_id(const char *pkey_name)
void ssl_load_ciphers(void)
{
ssl_cipher_methods[SSL_ENC_DES_IDX] = EVP_get_cipherbyname(SN_des_cbc);
ssl_cipher_methods[SSL_ENC_3DES_IDX] =
EVP_get_cipherbyname(SN_des_ede3_cbc);
ssl_cipher_methods[SSL_ENC_RC4_IDX] = EVP_get_cipherbyname(SN_rc4);
ssl_cipher_methods[SSL_ENC_RC2_IDX] = EVP_get_cipherbyname(SN_rc2_cbc);
#ifndef OPENSSL_NO_IDEA
ssl_cipher_methods[SSL_ENC_IDEA_IDX] = EVP_get_cipherbyname(SN_idea_cbc);
#else
ssl_cipher_methods[SSL_ENC_IDEA_IDX] = NULL;
#endif
ssl_cipher_methods[SSL_ENC_AES128_IDX] =
EVP_get_cipherbyname(SN_aes_128_cbc);
ssl_cipher_methods[SSL_ENC_AES256_IDX] =
EVP_get_cipherbyname(SN_aes_256_cbc);
ssl_cipher_methods[SSL_ENC_CAMELLIA128_IDX] =
EVP_get_cipherbyname(SN_camellia_128_cbc);
ssl_cipher_methods[SSL_ENC_CAMELLIA256_IDX] =
EVP_get_cipherbyname(SN_camellia_256_cbc);
ssl_cipher_methods[SSL_ENC_GOST89_IDX] =
EVP_get_cipherbyname(SN_gost89_cnt);
ssl_cipher_methods[SSL_ENC_SEED_IDX] = EVP_get_cipherbyname(SN_seed_cbc);
ssl_cipher_methods[SSL_ENC_AES128GCM_IDX] =
EVP_get_cipherbyname(SN_aes_128_gcm);
ssl_cipher_methods[SSL_ENC_AES256GCM_IDX] =
EVP_get_cipherbyname(SN_aes_256_gcm);
ssl_digest_methods[SSL_MD_MD5_IDX] = EVP_get_digestbyname(SN_md5);
ssl_mac_secret_size[SSL_MD_MD5_IDX] =
EVP_MD_size(ssl_digest_methods[SSL_MD_MD5_IDX]);
OPENSSL_assert(ssl_mac_secret_size[SSL_MD_MD5_IDX] >= 0);
ssl_digest_methods[SSL_MD_SHA1_IDX] = EVP_get_digestbyname(SN_sha1);
ssl_mac_secret_size[SSL_MD_SHA1_IDX] =
EVP_MD_size(ssl_digest_methods[SSL_MD_SHA1_IDX]);
OPENSSL_assert(ssl_mac_secret_size[SSL_MD_SHA1_IDX] >= 0);
ssl_digest_methods[SSL_MD_GOST94_IDX] =
EVP_get_digestbyname(SN_id_GostR3411_94);
if (ssl_digest_methods[SSL_MD_GOST94_IDX]) {
ssl_mac_secret_size[SSL_MD_GOST94_IDX] =
EVP_MD_size(ssl_digest_methods[SSL_MD_GOST94_IDX]);
OPENSSL_assert(ssl_mac_secret_size[SSL_MD_GOST94_IDX] >= 0);
}
ssl_digest_methods[SSL_MD_GOST89MAC_IDX] =
EVP_get_digestbyname(SN_id_Gost28147_89_MAC);
ssl_mac_pkey_id[SSL_MD_GOST89MAC_IDX] = get_optional_pkey_id("gost-mac");
if (ssl_mac_pkey_id[SSL_MD_GOST89MAC_IDX]) {
ssl_mac_secret_size[SSL_MD_GOST89MAC_IDX] = 32;
size_t i;
const ssl_cipher_table *t;
for (i = 0, t = ssl_cipher_table_cipher; i < SSL_ENC_NUM_IDX; i++, t++) {
if (t->nid == NID_undef)
ssl_cipher_methods[i] = NULL;
else
ssl_cipher_methods[i] = EVP_get_cipherbynid(t->nid);
}
ssl_digest_methods[SSL_MD_SHA256_IDX] = EVP_get_digestbyname(SN_sha256);
ssl_mac_secret_size[SSL_MD_SHA256_IDX] =
EVP_MD_size(ssl_digest_methods[SSL_MD_SHA256_IDX]);
ssl_digest_methods[SSL_MD_SHA384_IDX] = EVP_get_digestbyname(SN_sha384);
ssl_mac_secret_size[SSL_MD_SHA384_IDX] =
EVP_MD_size(ssl_digest_methods[SSL_MD_SHA384_IDX]);
for (i = 0, t = ssl_cipher_table_mac; i < SSL_MD_NUM_IDX; i++, t++) {
ssl_digest_methods[i] = EVP_get_digestbynid(t->nid);
if (ssl_digest_methods[i]) {
ssl_mac_secret_size[i] = EVP_MD_size(ssl_digest_methods[i]);
OPENSSL_assert(ssl_mac_secret_size[i] >= 0);
}
}
/* Make sure we can access MD5 and SHA1 */
OPENSSL_assert(ssl_digest_methods[SSL_MD_MD5_IDX] != NULL);
OPENSSL_assert(ssl_digest_methods[SSL_MD_SHA1_IDX] != NULL);
}
#ifndef OPENSSL_NO_COMP
@ -540,55 +556,9 @@ int ssl_cipher_get_evp(const SSL_SESSION *s, const EVP_CIPHER **enc,
if ((enc == NULL) || (md == NULL))
return 0;
switch (c->algorithm_enc) {
case SSL_DES:
i = SSL_ENC_DES_IDX;
break;
case SSL_3DES:
i = SSL_ENC_3DES_IDX;
break;
case SSL_RC4:
i = SSL_ENC_RC4_IDX;
break;
case SSL_RC2:
i = SSL_ENC_RC2_IDX;
break;
case SSL_IDEA:
i = SSL_ENC_IDEA_IDX;
break;
case SSL_eNULL:
i = SSL_ENC_NULL_IDX;
break;
case SSL_AES128:
i = SSL_ENC_AES128_IDX;
break;
case SSL_AES256:
i = SSL_ENC_AES256_IDX;
break;
case SSL_CAMELLIA128:
i = SSL_ENC_CAMELLIA128_IDX;
break;
case SSL_CAMELLIA256:
i = SSL_ENC_CAMELLIA256_IDX;
break;
case SSL_eGOST2814789CNT:
i = SSL_ENC_GOST89_IDX;
break;
case SSL_SEED:
i = SSL_ENC_SEED_IDX;
break;
case SSL_AES128GCM:
i = SSL_ENC_AES128GCM_IDX;
break;
case SSL_AES256GCM:
i = SSL_ENC_AES256GCM_IDX;
break;
default:
i = -1;
break;
}
i = ssl_cipher_info_lookup(ssl_cipher_table_cipher, c->algorithm_enc);
if ((i < 0) || (i >= SSL_ENC_NUM_IDX))
if (i == -1)
*enc = NULL;
else {
if (i == SSL_ENC_NULL_IDX)
@ -597,30 +567,8 @@ int ssl_cipher_get_evp(const SSL_SESSION *s, const EVP_CIPHER **enc,
*enc = ssl_cipher_methods[i];
}
switch (c->algorithm_mac) {
case SSL_MD5:
i = SSL_MD_MD5_IDX;
break;
case SSL_SHA1:
i = SSL_MD_SHA1_IDX;
break;
case SSL_SHA256:
i = SSL_MD_SHA256_IDX;
break;
case SSL_SHA384:
i = SSL_MD_SHA384_IDX;
break;
case SSL_GOST94:
i = SSL_MD_GOST94_IDX;
break;
case SSL_GOST89MAC:
i = SSL_MD_GOST89MAC_IDX;
break;
default:
i = -1;
break;
}
if ((i < 0) || (i >= SSL_MD_NUM_IDX)) {
i = ssl_cipher_info_lookup(ssl_cipher_table_mac, c->algorithm_mac);
if (i == -1) {
*md = NULL;
if (mac_pkey_type != NULL)
*mac_pkey_type = NID_undef;
@ -2073,3 +2021,25 @@ const SSL_CIPHER *SSL_CIPHER_find(SSL *ssl, const unsigned char *ptr)
{
return ssl->method->get_cipher_by_char(ptr);
}
int SSL_CIPHER_get_cipher_nid(const SSL_CIPHER *c)
{
int i;
if (c == NULL)
return -1;
i = ssl_cipher_info_lookup(ssl_cipher_table_cipher, c->algorithm_enc);
if (i == -1)
return -1;
return ssl_cipher_table_cipher[i].nid;
}
int SSL_CIPHER_get_digest_nid(const SSL_CIPHER *c)
{
int i;
if (c == NULL)
return -1;
i = ssl_cipher_info_lookup(ssl_cipher_table_mac, c->algorithm_mac);
if (i == -1)
return -1;
return ssl_cipher_table_mac[i].nid;
}