diff options
Diffstat (limited to 'src/libstrongswan/crypto/iv/iv_gen_seq.c')
| -rw-r--r-- | src/libstrongswan/crypto/iv/iv_gen_seq.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/src/libstrongswan/crypto/iv/iv_gen_seq.c b/src/libstrongswan/crypto/iv/iv_gen_seq.c index 98d0c15a6..4de13744d 100644 --- a/src/libstrongswan/crypto/iv/iv_gen_seq.c +++ b/src/libstrongswan/crypto/iv/iv_gen_seq.c @@ -15,6 +15,11 @@ #include "iv_gen_seq.h" +/** + * Magic value for the initial IV state + */ +#define SEQ_IV_INIT_STATE (~(u_int64_t)0) + typedef struct private_iv_gen_t private_iv_gen_t; /** @@ -28,6 +33,11 @@ struct private_iv_gen_t { iv_gen_t public; /** + * Previously passed sequence number to enforce uniqueness + */ + u_int64_t prev; + + /** * Salt to mask counter */ u_int8_t *salt; @@ -43,6 +53,19 @@ METHOD(iv_gen_t, get_iv, bool, { return FALSE; } + if (size < sizeof(u_int64_t)) + { + return FALSE; + } + if (this->prev != SEQ_IV_INIT_STATE && seq <= this->prev) + { + return FALSE; + } + if (seq == SEQ_IV_INIT_STATE) + { + return FALSE; + } + this->prev = seq; if (len > sizeof(u_int64_t)) { len = sizeof(u_int64_t); @@ -84,6 +107,7 @@ iv_gen_t *iv_gen_seq_create() .allocate_iv = _allocate_iv, .destroy = _destroy, }, + .prev = SEQ_IV_INIT_STATE, ); rng = lib->crypto->create_rng(lib->crypto, RNG_STRONG); |