diff options
Diffstat (limited to 'Userland/ntpquery.cpp')
| -rw-r--r-- | Userland/ntpquery.cpp | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/Userland/ntpquery.cpp b/Userland/ntpquery.cpp index 413aa9ea9e..1d8b94a0dc 100644 --- a/Userland/ntpquery.cpp +++ b/Userland/ntpquery.cpp @@ -58,6 +58,10 @@ struct [[gnu::packed]] NtpPacket NtpTimestamp origin_timestamp; NtpTimestamp receive_timestamp; NtpTimestamp transmit_timestamp; + + uint8_t leap_information() const { return li_vn_mode >> 6; } + uint8_t version_number() const { return (li_vn_mode >> 3) & 7; } + uint8_t mode() const { return li_vn_mode & 7; } }; static_assert(sizeof(NtpPacket) == 48); @@ -218,10 +222,27 @@ int main(int argc, char** argv) timeval kernel_receive_time; memcpy(&kernel_receive_time, CMSG_DATA(cmsg), sizeof(kernel_receive_time)); + // Checks 3 and 4 from end of section 5 of rfc4330. + if (packet.version_number() != 3 && packet.version_number() != 4) { + fprintf(stderr, "unexpected version number %d\n", packet.version_number()); + return 1; + } + if (packet.mode() != 4) { // 4 means "server", which should be the reply to our 3 ("client") request. + fprintf(stderr, "unexpected mode %d\n", packet.mode()); + return 1; + } + if (packet.stratum == 0 || packet.stratum >= 16) { + fprintf(stderr, "unexpected stratum value %d\n", packet.stratum); + return 1; + } if (packet.origin_timestamp != random_transmit_timestamp) { fprintf(stderr, "expected %#016llx as origin timestamp, got %#016llx\n", random_transmit_timestamp, packet.origin_timestamp); return 1; } + if (packet.transmit_timestamp == 0) { + fprintf(stderr, "got transmit_timestamp 0\n"); + return 1; + } NtpTimestamp origin_timestamp = ntp_timestamp_from_timeval(local_transmit_time); NtpTimestamp receive_timestamp = be64toh(packet.receive_timestamp); @@ -242,9 +263,9 @@ int main(int argc, char** argv) if (verbose) { printf("NTP response from %s:\n", inet_ntoa(peer_address.sin_addr)); - printf("Leap Information: %d\n", packet.li_vn_mode >> 6); - printf("Version Number: %d\n", (packet.li_vn_mode >> 3) & 7); - printf("Mode: %d\n", packet.li_vn_mode & 7); + printf("Leap Information: %d\n", packet.leap_information()); + printf("Version Number: %d\n", packet.version_number()); + printf("Mode: %d\n", packet.mode()); printf("Stratum: %d\n", packet.stratum); printf("Poll: %d\n", packet.stratum); printf("Precision: %d\n", packet.precision); |