diff options
| author | Luca <deri@ntop.org> | 2020-10-05 08:26:24 +0200 |
|---|---|---|
| committer | Luca <deri@ntop.org> | 2020-10-05 08:26:24 +0200 |
| commit | 05d93790e4d2b54d043bbb61b9978ccad64f2ab3 (patch) | |
| tree | df8c1c6c1413f70b59526e8ca3c3da014a0db06c | |
| parent | 32e4922c5aa203a3f250b3048cd5488c77ee1a04 (diff) | |
Added ndpi_quick_16_byte_hash
Warning fix
| -rw-r--r-- | example/reader_util.c | 2 | ||||
| -rw-r--r-- | src/include/ndpi_api.h.in | 1 | ||||
| -rw-r--r-- | src/lib/ndpi_utils.c | 30 |
3 files changed, 32 insertions, 1 deletions
diff --git a/example/reader_util.c b/example/reader_util.c index 7b1b6f271..eb87e8d2e 100644 --- a/example/reader_util.c +++ b/example/reader_util.c @@ -1075,7 +1075,7 @@ void process_ndpi_collected_info(struct ndpi_workflow * workflow, struct ndpi_fl } /* MDNS */ else if(is_ndpi_proto(flow, NDPI_PROTOCOL_MDNS)) { - char *name = flow->ndpi_flow->host_server_name; /* Trick to avoid warning(s) */ + char *name = (char*)flow->ndpi_flow->host_server_name; /* Trick to avoid warning(s) */ snprintf(flow->info, sizeof(flow->info), "%s", name); } /* UBNTAC2 */ diff --git a/src/include/ndpi_api.h.in b/src/include/ndpi_api.h.in index 14658962b..39fd6bfb3 100644 --- a/src/include/ndpi_api.h.in +++ b/src/include/ndpi_api.h.in @@ -1087,6 +1087,7 @@ extern "C" { u_int8_t num_clusters, u_int16_t *cluster_ids, struct ndpi_bin *centroids); + u_int32_t ndpi_quick_16_byte_hash(u_int8_t *in_16_bytes_long); #ifdef __cplusplus } #endif diff --git a/src/lib/ndpi_utils.c b/src/lib/ndpi_utils.c index b96f52531..634b02d59 100644 --- a/src/lib/ndpi_utils.c +++ b/src/lib/ndpi_utils.c @@ -1765,3 +1765,33 @@ ndpi_http_method ndpi_http_str2method(const char* method, ssize_t method_len) { return(NDPI_HTTP_METHOD_UNKNOWN); } + +/* ******************************************************************** */ + +#define ROR64(x,r) (((x)>>(r))|((x)<<(64-(r)))) + +/* + 'in_16_bytes_long` points to some 16 byte memory data to be hashed; + two independent 64-bit linear congruential generators are applied + results are mixed, scrambled and cast to 32-bit +*/ +u_int32_t ndpi_quick_16_byte_hash(u_int8_t *in_16_bytes_long) { + u_int64_t a = *(u_int64_t*)(in_16_bytes_long + 0); + u_int64_t c = *(u_int64_t*)(in_16_bytes_long + 8); + + // multipliers are taken from sprng.org, addends are prime + a = a * 0x2c6fe96ee78b6955 + 0x9af64480a3486659; + c = c * 0x369dea0f31a53f85 + 0xd0c6225445b76b5b; + + // mix results + a += c; + + // final scramble + a ^= ROR64(a, 13) ^ ROR64(a, 7); + + // down-casting, also taking advantage of upper half + a ^= a >> 32; + + return((u_int32_t)a); +} + |