src/header.c

   1 /*======================================================================*
   2  * Copyright (c) 2008, Yahoo! Inc. All rights reserved.                 *
   3  *                                                                      *
   4  * Licensed under the New BSD License (the "License"); you may not use  *
   5  * this file except in compliance with the License.  Unless required    *
   6  * by applicable law or agreed to in writing, software distributed      *
   7  * under the License is distributed on an "AS IS" BASIS, WITHOUT        *
   8  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.     *
   9  * See the License for the specific language governing permissions and  *
  10  * limitations under the License. See accompanying LICENSE file.        *
  11  *======================================================================*/
  12
  13 #include "config.h"
  14
  15 #include "header.h"
  16
  17 #include "log.h"
  18 #include "opt.h"
  19 #include "stats.h"
  20
  21 #include "lwes.h"
  22 #include "marshal.h"
  23
  24 #include <sys/socket.h>
  25 #include <netinet/in.h>
  26 #include <arpa/inet.h>
  27
  28 #define ntohll(x) ( ( (uint64_t)(ntohl( (uint32_t)((x << 32) >> 32) )) << 32) | ntohl( ((uint32_t)(x >> 32)) ) )
  29
  30 void header_add(void* buf, int count, unsigned long long tm, unsigned long addr, unsigned short port)
  31 {
  32   unsigned char*     cp = (unsigned char*)buf;
  33
  34   marshal_short(cp, count);    /* Size of message body. */
  35   marshal_ulong_long(cp, tm);  /* Now in msec. */
  36   marshal_long(cp, addr);      /* Sender IP address. */
  37   marshal_short(cp, port);     /* Sender port number. */
  38   marshal_short(cp, arg_site); /* Site ID number */
  39   /* TODO: should be perfectly alright, but un-QA'd  marshal_long(cp, 0); */
  40   /* reserved */
  41 }
  42
  43 int header_is_rotate (void* buf)
  44 {
  45   return toknam_eq((unsigned char *)buf + HEADER_LENGTH,
  46                    (unsigned char *)ROTATE_COMMAND);
  47   LOG_PROG("Command::Rotate message received.\n");
  48 }
  49
  50 void header_fingerprint(void* buf, struct packet_check* pc)
  51 {
  52   unsigned char* cp = (unsigned char*)buf;
  53   long long zero = 0LL;
  54   unsigned long long tm;
  55   short length;
  56
  57   /* Extract the timestamp. */
  58   unmarshal_short(cp, length);
  59   unmarshal_ulong_long(cp, tm);
  60
  61   /* Add phony timestamp of zero. */
  62   cp -= 8;
  63   marshal_long_long(cp, zero);
  64
  65   pc->received = tm;
  66   /* pc->md5 = md5(); */
  67 }
  68
  69 /////////////////////////////////////////////////////////////////////////////
  70 // It's a small thing, but toknam_eq() is quicker than memcmp().
  71 //   * memcmp does a tremendous amount of setup before comparing the first
  72 //     character (it's designed to compare large strings efficently)
  73 //   * we don't care if greater-than or less-than, just equal or not
  74 //   * syntactically simpler (taking advantage of token's length byte)
  75 int toknam_eq(const unsigned char* toknam, const unsigned char* nam)
  76 {
  77   unsigned char len = *nam+1 ;
  78   while ( *toknam++ == *nam++ )
  79     if ( --len == 0 )
  80       return 1 ;
  81   return 0 ;
  82 }
  83
  84 /////////////////////////////////////////////////////////////////////////////
  85
  86 void header_print (const char* buf)
  87 {
  88   LOG_INF("header payload length: %u\n",   header_payload_length(buf));
  89   LOG_INF("receipt time:          %llu\n", header_receipt_time(buf));
  90   LOG_INF("now:                   %llu\n", time(NULL)*1000L);
  91   LOG_INF("sender IP text:        %s\n",   header_sender_ip_formatted(buf));
  92   LOG_INF("sender port:           %u\n",   header_sender_port(buf));
  93   LOG_INF("site id:               %u\n",   header_site_id(buf));
  94 }
  95
  96 static uint16_t header_uint16(const char* bytes) {
  97   return ntohs(*((uint16_t*) bytes));
  98 }
  99
 100 static uint32_t header_uint32(const char* bytes) {
 101   return ntohl(*((uint32_t*) bytes));
 102 }
 103
 104 static uint64_t header_uint64(const char* bytes) {
 105   return (((uint64_t)header_uint32(bytes))<<32) | header_uint32(bytes+4);
 106 }
 107
 108 uint16_t header_payload_length(const char* header)
 109 {
 110   return header_uint16(header);
 111 }
 112
 113 uint64_t header_receipt_time(const char* header) {
 114   return header_uint64(header+RECEIPT_TIME_OFFSET);
 115 }
 116
 117 const char* header_sender_ip_formatted(const char* header) {
 118   struct in_addr addr = { header_uint32(header+SENDER_IP_OFFSET) };
 119   return inet_ntoa(addr);
 120 }
 121
 122 uint16_t header_sender_port(const char* header) {
 123   return header_uint16(header+SENDER_PORT_OFFSET);
 124 }
 125
 126 uint16_t header_site_id(const char* header) {
 127   return header_uint16(header+SITE_ID_OFFSET);
 128 }
 129
 130 /* end-of-file */