diff options
Diffstat (limited to 'src/llc.cpp')
| -rw-r--r-- | src/llc.cpp | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/src/llc.cpp b/src/llc.cpp index b1609617..9c5581fb 100644 --- a/src/llc.cpp +++ b/src/llc.cpp @@ -160,3 +160,18 @@ bool gprs_llc::is_frame_expired(struct timeval *tv_now, struct timeval *tv) return timercmp(tv_now, tv, >); } + +bool gprs_llc::is_user_data_frame(uint8_t *data, size_t len) +{ + if (len < 2) + return false; + + if ((data[0] & 0x0f) == 1 /* GPRS_SAPI_GMM */) + return false; + + if ((data[0] & 0x0e) != 0xc0 /* LLC UI */) + /* It is not an LLC UI frame */ + return false; + + return true; +} |