diff options
Diffstat (limited to 'src/libstrongswan/crypto/iv/iv_gen_seq.c')
| -rw-r--r-- | src/libstrongswan/crypto/iv/iv_gen_seq.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/src/libstrongswan/crypto/iv/iv_gen_seq.c b/src/libstrongswan/crypto/iv/iv_gen_seq.c index 4de13744d..9f99c5192 100644 --- a/src/libstrongswan/crypto/iv/iv_gen_seq.c +++ b/src/libstrongswan/crypto/iv/iv_gen_seq.c @@ -19,6 +19,7 @@ * Magic value for the initial IV state */ #define SEQ_IV_INIT_STATE (~(u_int64_t)0) +#define SEQ_IV_HIGH_MASK (1ULL << 63) typedef struct private_iv_gen_t private_iv_gen_t; @@ -33,9 +34,14 @@ struct private_iv_gen_t { iv_gen_t public; /** - * Previously passed sequence number to enforce uniqueness + * Previously passed sequence number in lower space to enforce uniqueness */ - u_int64_t prev; + u_int64_t prevl; + + /** + * Previously passed sequence number in upper space to enforce uniqueness + */ + u_int64_t prevh; /** * Salt to mask counter @@ -57,15 +63,26 @@ METHOD(iv_gen_t, get_iv, bool, { return FALSE; } - if (this->prev != SEQ_IV_INIT_STATE && seq <= this->prev) + if (this->prevl != SEQ_IV_INIT_STATE && seq <= this->prevl) { - return FALSE; + seq |= SEQ_IV_HIGH_MASK; + if (this->prevh != SEQ_IV_INIT_STATE && seq <= this->prevh) + { + return FALSE; + } } - if (seq == SEQ_IV_INIT_STATE) + if ((seq | SEQ_IV_HIGH_MASK) == SEQ_IV_INIT_STATE) { return FALSE; } - this->prev = seq; + if (seq & SEQ_IV_HIGH_MASK) + { + this->prevh = seq; + } + else + { + this->prevl = seq; + } if (len > sizeof(u_int64_t)) { len = sizeof(u_int64_t); @@ -107,7 +124,8 @@ iv_gen_t *iv_gen_seq_create() .allocate_iv = _allocate_iv, .destroy = _destroy, }, - .prev = SEQ_IV_INIT_STATE, + .prevl = SEQ_IV_INIT_STATE, + .prevh = SEQ_IV_INIT_STATE, ); rng = lib->crypto->create_rng(lib->crypto, RNG_STRONG); |