diff options
Diffstat (limited to 'crypto/dh_helper.c')
| -rw-r--r-- | crypto/dh_helper.c | 43 |
1 files changed, 27 insertions, 16 deletions
diff --git a/crypto/dh_helper.c b/crypto/dh_helper.c index 24fdb2ecaa85..edacda5f6a4d 100644 --- a/crypto/dh_helper.c +++ b/crypto/dh_helper.c @@ -14,10 +14,12 @@ #include <crypto/dh.h> #include <crypto/kpp.h> -#define DH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 3 * sizeof(int)) +#define DH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 4 * sizeof(int)) -static inline u8 *dh_pack_data(void *dst, const void *src, size_t size) +static inline u8 *dh_pack_data(u8 *dst, u8 *end, const void *src, size_t size) { + if (!dst || size > end - dst) + return NULL; memcpy(dst, src, size); return dst + size; } @@ -30,7 +32,7 @@ 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->g_size; + return p->key_size + p->p_size + p->q_size + p->g_size; } unsigned int crypto_dh_key_len(const struct dh *p) @@ -42,25 +44,27 @@ EXPORT_SYMBOL_GPL(crypto_dh_key_len); int crypto_dh_encode_key(char *buf, unsigned int len, const struct dh *params) { u8 *ptr = buf; + u8 * const end = ptr + len; struct kpp_secret secret = { .type = CRYPTO_KPP_SECRET_TYPE_DH, .len = len }; - if (unlikely(!buf)) + if (unlikely(!len)) return -EINVAL; - if (len != crypto_dh_key_len(params)) + ptr = dh_pack_data(ptr, end, &secret, sizeof(secret)); + 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; - - ptr = dh_pack_data(ptr, &secret, sizeof(secret)); - ptr = dh_pack_data(ptr, ¶ms->key_size, sizeof(params->key_size)); - ptr = dh_pack_data(ptr, ¶ms->p_size, sizeof(params->p_size)); - ptr = dh_pack_data(ptr, ¶ms->g_size, sizeof(params->g_size)); - ptr = dh_pack_data(ptr, params->key, params->key_size); - ptr = dh_pack_data(ptr, params->p, params->p_size); - dh_pack_data(ptr, params->g, params->g_size); - return 0; } EXPORT_SYMBOL_GPL(crypto_dh_encode_key); @@ -79,6 +83,7 @@ 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; @@ -88,7 +93,7 @@ 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->g_size > params->p_size || params->q_size > params->p_size) return -EINVAL; /* Don't allocate memory. Set pointers to data within @@ -96,7 +101,9 @@ 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->g = (void *)(ptr + params->key_size + params->p_size); + params->q = (void *)(ptr + params->key_size + params->p_size); + params->g = (void *)(ptr + params->key_size + params->p_size + + params->q_size); /* * Don't permit 'p' to be 0. It's not a prime number, and it's subject @@ -106,6 +113,10 @@ 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); |