diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/lib/ndpi_main.c | 3 | ||||
| -rw-r--r-- | src/lib/ndpi_utils.c | 14 |
2 files changed, 9 insertions, 8 deletions
diff --git a/src/lib/ndpi_main.c b/src/lib/ndpi_main.c index c9ca62ea3..c1fb6fc1d 100644 --- a/src/lib/ndpi_main.c +++ b/src/lib/ndpi_main.c @@ -3064,9 +3064,8 @@ u_int16_t ndpi_guess_protocol_id(struct ndpi_detection_module_struct *ndpi_str, ndpi_set_risk(ndpi_str, flow, NDPI_SUSPICIOUS_ENTROPY); } - struct ndpi_icmphdr * const icmphdr = (struct ndpi_icmphdr *)packet->payload; u_int16_t chksm = ndpi_calculate_icmp4_checksum(packet->payload, packet->payload_packet_len); - if (icmphdr->checksum != chksm) { + if (chksm) { ndpi_set_risk(ndpi_str, flow, NDPI_MALFORMED_PACKET); } } diff --git a/src/lib/ndpi_utils.c b/src/lib/ndpi_utils.c index 313448c51..efb7d26f2 100644 --- a/src/lib/ndpi_utils.c +++ b/src/lib/ndpi_utils.c @@ -2300,24 +2300,26 @@ float ndpi_entropy(u_int8_t const * const buf, size_t len) { } /* ******************************************************************** */ +static inline uint16_t get_n16bit(uint8_t const * cbuf) { + uint16_t r = ((uint16_t)cbuf[0]) | (((uint16_t)cbuf[1]) << 8); + return r; +} -u_int16_t ndpi_calculate_icmp4_checksum(u_int8_t const * const buf, size_t len) { - u_int16_t const * sbuf = (u_int16_t *)buf; +u_int16_t ndpi_calculate_icmp4_checksum(const u_int8_t * buf, size_t len) { u_int32_t checksum = 0; /* * The first two bytes of the icmp header are required. * The next two bytes is the checksum, which we want to ignore. */ - checksum += *sbuf++; len -= 2; /* icmp->type, icmp->code */ - sbuf++; len -= 2; /* icmp->checksum */ for (; len > 1; len -= 2) { - checksum += *sbuf++; + checksum += get_n16bit(buf); + buf += 2; } if (len == 1) { - checksum += *(u_int8_t *)sbuf; + checksum += *buf; } checksum = (checksum >> 16) + (checksum & 0xFFFF); |