The only current user of the DH KPP algorithm, the keyctl(KEYCTL_DH_COMPUTE) syscall, doesn't set the domain parameter ->q in struct dh. Remove it and any associated (de)serialization code in crypto_dh_encode_key() and crypto_dh_decode_key. Adjust the encoded ->secret values in testmgr's DH test vectors accordingly. Note that the dh-generic implementation would have initialized its struct dh_ctx's ->q from the decoded struct dh's ->q, if present. If this struct dh_ctx's ->q would ever have been non-NULL, it would have enabled a full key validation as specified in NIST SP800-56A in dh_is_pubkey_valid(). However, as outlined above, ->q is always NULL in practice and the full key validation code is effectively dead. A later patch will make dh_is_pubkey_valid() to calculate Q from P on the fly, if possible, so don't remove struct dh_ctx's ->q now, but leave it there until that has happened. Signed-off-by: Nicolai Stange <nstange@xxxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxx> --- crypto/dh.c | 6 ------ crypto/dh_helper.c | 17 ++++------------- crypto/testmgr.h | 16 ++++++---------- include/crypto/dh.h | 4 ---- 4 files changed, 10 insertions(+), 33 deletions(-) diff --git a/crypto/dh.c b/crypto/dh.c index 27e62a2a8027..abc2a72c8271 100644 --- a/crypto/dh.c +++ b/crypto/dh.c @@ -62,12 +62,6 @@ static int dh_set_params(struct dh_ctx *ctx, struct dh *params) if (!ctx->p) return -EINVAL; - if (params->q && params->q_size) { - ctx->q = mpi_read_raw_data(params->q, params->q_size); - if (!ctx->q) - return -EINVAL; - } - ctx->g = mpi_read_raw_data(params->g, params->g_size); if (!ctx->g) return -EINVAL; diff --git a/crypto/dh_helper.c b/crypto/dh_helper.c index 9fd5a42eea15..aabc91e4f63f 100644 --- a/crypto/dh_helper.c +++ b/crypto/dh_helper.c @@ -10,7 +10,7 @@ #include <crypto/dh.h> #include <crypto/kpp.h> -#define DH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 4 * sizeof(int)) +#define DH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 3 * sizeof(int)) static inline u8 *dh_pack_data(u8 *dst, u8 *end, const void *src, size_t size) { @@ -28,7 +28,7 @@ static inline const u8 *dh_unpack_data(void *dst, const void *src, size_t size) static inline unsigned int dh_data_size(const struct dh *p) { - return p->key_size + p->p_size + p->q_size + p->g_size; + return p->key_size + p->p_size + p->g_size; } unsigned int crypto_dh_key_len(const struct dh *p) @@ -53,11 +53,9 @@ int crypto_dh_encode_key(char *buf, unsigned int len, const struct dh *params) ptr = dh_pack_data(ptr, end, ¶ms->key_size, sizeof(params->key_size)); ptr = dh_pack_data(ptr, end, ¶ms->p_size, sizeof(params->p_size)); - ptr = dh_pack_data(ptr, end, ¶ms->q_size, sizeof(params->q_size)); ptr = dh_pack_data(ptr, end, ¶ms->g_size, sizeof(params->g_size)); ptr = dh_pack_data(ptr, end, params->key, params->key_size); ptr = dh_pack_data(ptr, end, params->p, params->p_size); - ptr = dh_pack_data(ptr, end, params->q, params->q_size); ptr = dh_pack_data(ptr, end, params->g, params->g_size); if (ptr != end) return -EINVAL; @@ -79,7 +77,6 @@ int crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params) ptr = dh_unpack_data(¶ms->key_size, ptr, sizeof(params->key_size)); ptr = dh_unpack_data(¶ms->p_size, ptr, sizeof(params->p_size)); - ptr = dh_unpack_data(¶ms->q_size, ptr, sizeof(params->q_size)); ptr = dh_unpack_data(¶ms->g_size, ptr, sizeof(params->g_size)); if (secret.len != crypto_dh_key_len(params)) return -EINVAL; @@ -89,7 +86,7 @@ int crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params) * some drivers assume otherwise. */ if (params->key_size > params->p_size || - params->g_size > params->p_size || params->q_size > params->p_size) + params->g_size > params->p_size) return -EINVAL; /* Don't allocate memory. Set pointers to data within @@ -97,9 +94,7 @@ int crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params) */ params->key = (void *)ptr; params->p = (void *)(ptr + params->key_size); - params->q = (void *)(ptr + params->key_size + params->p_size); - params->g = (void *)(ptr + params->key_size + params->p_size + - params->q_size); + params->g = (void *)(ptr + params->key_size + params->p_size); /* * Don't permit 'p' to be 0. It's not a prime number, and it's subject @@ -109,10 +104,6 @@ int crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params) if (memchr_inv(params->p, 0, params->p_size) == NULL) return -EINVAL; - /* It is permissible to not provide Q. */ - if (params->q_size == 0) - params->q = NULL; - return 0; } EXPORT_SYMBOL_GPL(crypto_dh_decode_key); diff --git a/crypto/testmgr.h b/crypto/testmgr.h index 85ccf811f5e7..31da6fd3cfe7 100644 --- a/crypto/testmgr.h +++ b/crypto/testmgr.h @@ -1246,17 +1246,15 @@ static const struct kpp_testvec dh_tv_template[] = { .secret = #ifdef __LITTLE_ENDIAN "\x01\x00" /* type */ - "\x15\x02" /* len */ + "\x11\x02" /* len */ "\x00\x01\x00\x00" /* key_size */ "\x00\x01\x00\x00" /* p_size */ - "\x00\x00\x00\x00" /* q_size */ "\x01\x00\x00\x00" /* g_size */ #else "\x00\x01" /* type */ - "\x02\x15" /* len */ + "\x02\x11" /* len */ "\x00\x00\x01\x00" /* key_size */ "\x00\x00\x01\x00" /* p_size */ - "\x00\x00\x00\x00" /* q_size */ "\x00\x00\x00\x01" /* g_size */ #endif /* xa */ @@ -1346,7 +1344,7 @@ static const struct kpp_testvec dh_tv_template[] = { "\xd3\x34\x49\xad\x64\xa6\xb1\xc0\x59\x28\x75\x60\xa7\x8a\xb0\x11" "\x56\x89\x42\x74\x11\xf5\xf6\x5e\x6f\x16\x54\x6a\xb1\x76\x4d\x50" "\x8a\x68\xc1\x5b\x82\xb9\x0d\x00\x32\x50\xed\x88\x87\x48\x92\x17", - .secret_size = 533, + .secret_size = 529, .b_public_size = 256, .expected_a_public_size = 256, .expected_ss_size = 256, @@ -1355,17 +1353,15 @@ static const struct kpp_testvec dh_tv_template[] = { .secret = #ifdef __LITTLE_ENDIAN "\x01\x00" /* type */ - "\x15\x02" /* len */ + "\x11\x02" /* len */ "\x00\x01\x00\x00" /* key_size */ "\x00\x01\x00\x00" /* p_size */ - "\x00\x00\x00\x00" /* q_size */ "\x01\x00\x00\x00" /* g_size */ #else "\x00\x01" /* type */ - "\x02\x15" /* len */ + "\x02\x11" /* len */ "\x00\x00\x01\x00" /* key_size */ "\x00\x00\x01\x00" /* p_size */ - "\x00\x00\x00\x00" /* q_size */ "\x00\x00\x00\x01" /* g_size */ #endif /* xa */ @@ -1455,7 +1451,7 @@ static const struct kpp_testvec dh_tv_template[] = { "\x5e\x5a\x64\xbd\xf6\x85\x04\xe8\x28\x6a\xac\xef\xce\x19\x8e\x9a" "\xfe\x75\xc0\x27\x69\xe3\xb3\x7b\x21\xa7\xb1\x16\xa4\x85\x23\xee" "\xb0\x1b\x04\x6e\xbd\xab\x16\xde\xfd\x86\x6b\xa9\x95\xd7\x0b\xfd", - .secret_size = 533, + .secret_size = 529, .b_public_size = 256, .expected_a_public_size = 256, .expected_ss_size = 256, diff --git a/include/crypto/dh.h b/include/crypto/dh.h index d71e9858ab86..2585f0e6bb69 100644 --- a/include/crypto/dh.h +++ b/include/crypto/dh.h @@ -24,21 +24,17 @@ * * @key: Private DH key * @p: Diffie-Hellman parameter P - * @q: Diffie-Hellman parameter Q * @g: Diffie-Hellman generator G * @key_size: Size of the private DH key * @p_size: Size of DH parameter P - * @q_size: Size of DH parameter Q * @g_size: Size of DH generator G */ struct dh { void *key; void *p; - void *q; void *g; unsigned int key_size; unsigned int p_size; - unsigned int q_size; unsigned int g_size; }; -- 2.26.2