1 | /* A much more complicated libtrace program designed to demonstrate combining |
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2 | * various elements of libtrace to create a useful tool. |
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3 | * |
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4 | * Specifically, this program calculates the amount of header overhead for |
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5 | * TCP and UDP traffic compared with the amount of application payload. It |
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6 | * writes the byte counts regularly to generate data suitable for a time series |
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7 | * graph. |
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8 | * |
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9 | */ |
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10 | #include "libtrace.h" |
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11 | #include <stdio.h> |
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12 | #include <inttypes.h> |
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13 | #include <err.h> |
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14 | #include <assert.h> |
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15 | #include <getopt.h> |
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16 | #include <string.h> |
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17 | #include <stdlib.h> |
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18 | |
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19 | uint64_t udp_header = 0; |
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20 | uint64_t udp_payload = 0; |
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21 | uint64_t tcp_header = 0; |
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22 | uint64_t tcp_payload = 0; |
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23 | uint64_t not_ip = 0; |
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24 | |
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25 | uint32_t next_report = 0; |
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26 | uint32_t interval = 10; /* Reporting interval defaults to 10 seconds. */ |
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27 | |
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28 | /* This enum defines values for all the possible protocol cases that this |
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29 | * program is interested in */ |
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30 | typedef enum { |
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31 | DEMO_PROTO_TCP, /* The packet is a TCP packet */ |
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32 | DEMO_PROTO_UDP, /* The packet is a UDP packet */ |
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33 | DEMO_PROTO_NOTIP, /* The packet is NOT an IP packet */ |
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34 | DEMO_PROTO_OTHER, /* The packet is none of the above */ |
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35 | DEMO_PROTO_UNKNOWN /* Haven't yet determined anything about the |
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36 | packet */ |
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37 | } demo_proto_t; |
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38 | |
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39 | static void print_stats() { |
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40 | printf("%u,%" PRIu64 ",%" PRIu64 ",%" PRIu64 ",%" PRIu64 ",%" PRIu64 "\n", |
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41 | next_report, tcp_header, tcp_payload, udp_header, |
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42 | udp_payload, not_ip); |
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43 | } |
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44 | |
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45 | static void check_report(libtrace_packet_t *packet) { |
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46 | struct timeval ts; |
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47 | |
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48 | /* Get the timestamp for the current packet */ |
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49 | ts = trace_get_timeval(packet); |
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50 | |
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51 | /* If next_report is zero, then this is the first packet from the |
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52 | * trace so we need to determine the time at which the first report |
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53 | * must occur, i.e. "interval" seconds from now. */ |
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54 | |
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55 | if (next_report == 0) { |
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56 | next_report = ts.tv_sec + interval; |
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57 | |
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58 | /* Good opportunity to print some column headings */ |
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59 | printf("Time,TCP Headers,TCP Payload,UDP Headers,UDP Payload,Not IP\n"); |
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60 | } |
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61 | |
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62 | /* Check whether we need to report our stats |
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63 | * |
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64 | * Compare the timestamp for the current packet against the time that |
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65 | * the next report is due, a la timedemo.c |
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66 | */ |
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67 | |
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68 | while ((uint32_t)ts.tv_sec > next_report) { |
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69 | /* Print all our stats */ |
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70 | print_stats(); |
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71 | |
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72 | /* Reset the counters */ |
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73 | tcp_header = 0; |
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74 | tcp_payload = 0; |
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75 | udp_header = 0; |
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76 | udp_payload = 0; |
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77 | not_ip = 0; |
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78 | |
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79 | /* Determine when the next report is due */ |
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80 | next_report += interval; |
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81 | } |
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82 | } |
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83 | |
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84 | /* Calculates the number of bytes consumed by meta-data headers such as |
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85 | * Linux SLL, RadioTap, etc. |
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86 | */ |
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87 | static uint64_t calc_meta_size(libtrace_packet_t *packet) { |
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88 | |
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89 | uint64_t meta_size = 0; |
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90 | void *meta_ptr = NULL; |
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91 | libtrace_linktype_t ltype; |
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92 | uint32_t remaining; |
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93 | uint32_t prev_rem; |
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94 | |
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95 | /* Get a pointer to the meta-data header */ |
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96 | meta_ptr = trace_get_packet_meta(packet, <ype, &remaining); |
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97 | |
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98 | /* If the result is NULL, there are no meta-data headers present */ |
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99 | if (meta_ptr == NULL) |
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100 | return meta_size; |
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101 | |
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102 | |
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103 | /* Skip over any subsequent meta-data headers */ |
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104 | while (remaining > 0) { |
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105 | prev_rem = remaining; |
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106 | void *nexthdr = trace_get_payload_from_meta(meta_ptr, |
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107 | <ype, &remaining); |
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108 | |
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109 | /* If nexthdr is NULL, the current header is NOT a meta-data |
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110 | * header (and is almost certainly a link layer header) */ |
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111 | if (nexthdr == NULL) |
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112 | break; |
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113 | |
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114 | /* Sanity check as remaining should never get larger! */ |
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115 | assert(prev_rem >= remaining); |
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116 | |
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117 | /* Otherwise the header we called get_payload on was a |
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118 | * meta-data header so we need to add its length to the total |
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119 | * meta header size */ |
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120 | meta_size += (prev_rem - remaining); |
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121 | |
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122 | /* Prepare ourselves for the next pass through the loop */ |
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123 | meta_ptr = nexthdr; |
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124 | } |
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125 | |
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126 | return meta_size; |
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127 | |
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128 | |
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129 | } |
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130 | |
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131 | /* Calculates the number of bytes consumed by link layer headers. Note that |
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132 | * this will include any "layer 2.5" headers such as MPLS, VLAN or PPP. |
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133 | */ |
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134 | static uint64_t calc_link_size(libtrace_packet_t *packet) { |
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135 | void *link_ptr; |
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136 | void *nexthdr; |
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137 | libtrace_linktype_t linktype; |
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138 | uint32_t remaining; |
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139 | uint32_t prev_rem; |
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140 | uint16_t ethertype; |
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141 | |
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142 | uint64_t link_size = 0; |
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143 | |
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144 | /* Start by finding the layer 2 header */ |
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145 | link_ptr = trace_get_layer2(packet, &linktype, &remaining); |
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146 | |
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147 | /* If there is no layer 2 header, the total link layer has to be |
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148 | * zero bytes in size */ |
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149 | if (link_ptr == NULL) |
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150 | return link_size; |
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151 | |
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152 | /* Calculate the size of the first layer 2 header by comparing |
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153 | * remaining before and after we call trace_get_payload_from_layer2 |
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154 | */ |
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155 | prev_rem = remaining; |
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156 | nexthdr = trace_get_payload_from_layer2(link_ptr, linktype, |
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157 | ðertype, &remaining); |
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158 | |
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159 | /* Sanity check - remaining should never get larger! */ |
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160 | assert(prev_rem >= remaining); |
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161 | /* Add the size of the layer 2 header to our overall link layer size */ |
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162 | link_size += (prev_rem - remaining); |
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163 | |
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164 | /* Skip over any layer 2.5 headers, adding their size to our total |
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165 | * link layer size. */ |
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166 | while (remaining > 0) { |
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167 | if (nexthdr == NULL) |
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168 | break; |
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169 | prev_rem = remaining; |
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170 | |
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171 | /* Ethertype will always contain the type of the current |
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172 | * header that we are up to, thanks to the efforts of the |
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173 | * trace_get_payload_from_* functions */ |
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174 | switch(ethertype) { |
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175 | case 0x8100: /* VLAN */ |
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176 | nexthdr = trace_get_payload_from_vlan( |
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177 | nexthdr, ðertype, &remaining); |
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178 | break; |
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179 | case 0x8847: /* MPLS */ |
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180 | nexthdr = trace_get_payload_from_mpls( |
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181 | nexthdr, ðertype, &remaining); |
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182 | break; |
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183 | case 0x8864: /* PPPoE */ |
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184 | /* This will also skip the PPP header */ |
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185 | nexthdr = trace_get_payload_from_pppoe( |
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186 | nexthdr, ðertype, &remaining); |
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187 | break; |
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188 | default: |
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189 | /* This is just to provide a stopping condition |
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190 | * for the while loop. */ |
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191 | nexthdr = NULL; |
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192 | } |
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193 | |
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194 | /* If we have reached a non-layer 2.5 header, i.e. IP, we |
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195 | * want to fall out and return the total size */ |
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196 | if (nexthdr == NULL) |
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197 | break; |
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198 | |
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199 | /* Otherwise, add the length of the skipped header to the |
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200 | * total, being sure to perform our usual sanity check first */ |
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201 | assert(prev_rem >= remaining); |
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202 | link_size += (prev_rem - remaining); |
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203 | |
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204 | } |
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205 | |
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206 | /* Return the total link layer size */ |
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207 | return link_size; |
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208 | } |
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209 | |
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210 | /* Calculates the number of bytes consumed by IP headers, including IPv6 */ |
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211 | static uint64_t calc_ip_size(libtrace_packet_t *packet, demo_proto_t *proto) { |
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212 | |
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213 | uint64_t ip_size = 0; |
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214 | |
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215 | void *ip_hdr; |
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216 | void *nexthdr = NULL;; |
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217 | uint16_t ethertype; |
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218 | uint8_t protocol; |
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219 | uint32_t remaining; |
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220 | uint32_t prev_rem; |
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221 | libtrace_ip6_t *ip6; |
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222 | |
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223 | /* Start by finding the first layer 3 header */ |
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224 | ip_hdr = trace_get_layer3(packet, ðertype, &remaining); |
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225 | |
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226 | /* If no layer 3 headers are present, be sure to set proto |
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227 | * appropriately so the total header length is added to the right |
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228 | * category */ |
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229 | if (ip_hdr == NULL) { |
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230 | *proto = DEMO_PROTO_NOTIP; |
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231 | return ip_size; |
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232 | } |
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233 | |
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234 | prev_rem = remaining; |
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235 | |
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236 | /* Unlike at the link layer, there is less scope for endlessly stacked |
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237 | * headers so we don't need a fancy while loop */ |
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238 | |
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239 | /* Remember, ethertype tells us the type of the layer 3 header so we |
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240 | * can cast appropriately */ |
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241 | switch(ethertype) { |
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242 | case 0x0800: /* IPv4 */ |
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243 | /* Skip past the IPv4 header */ |
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244 | nexthdr = trace_get_payload_from_ip(ip_hdr, &protocol, |
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245 | &remaining); |
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246 | |
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247 | /* Check for v6 over v4 and skip over it if present */ |
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248 | if (nexthdr && protocol == 41) { |
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249 | ip6 = (libtrace_ip6_t *)nexthdr; |
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250 | nexthdr = trace_get_payload_from_ip6( |
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251 | ip6, &protocol, &remaining); |
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252 | } |
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253 | break; |
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254 | case 0x86DD: /* IPv6 */ |
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255 | /* Skip past the IPv6 header */ |
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256 | ip6 = (libtrace_ip6_t *)ip_hdr; |
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257 | nexthdr = trace_get_payload_from_ip6(ip6, &protocol, |
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258 | &remaining); |
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259 | break; |
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260 | default: |
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261 | /* Somehow we managed to get a layer 3 header that is |
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262 | * neither v4 nor v6 */ |
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263 | *proto = DEMO_PROTO_NOTIP; |
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264 | return ip_size; |
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265 | } |
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266 | |
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267 | /* Update our layer 3 size with the number of bytes we just skipped |
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268 | * past */ |
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269 | assert(prev_rem >= remaining); |
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270 | ip_size += (prev_rem - remaining); |
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271 | |
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272 | /* We can also use the protocol value from the get_payload function |
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273 | * to determine the transport layer protocol */ |
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274 | if (protocol == 6) |
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275 | *proto = DEMO_PROTO_TCP; |
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276 | else if (protocol == 17) |
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277 | *proto = DEMO_PROTO_UDP; |
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278 | else |
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279 | *proto = DEMO_PROTO_OTHER; |
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280 | |
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281 | /* Return our total layer 3 size */ |
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282 | return ip_size; |
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283 | |
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284 | } |
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285 | |
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286 | /* Calculates the number of bytes consumed by the transport header, including |
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287 | * options etc. */ |
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288 | static uint64_t calc_transport_size(libtrace_packet_t *packet) { |
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289 | |
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290 | uint64_t trans_size = 0; |
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291 | |
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292 | void *transport; |
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293 | void *nexthdr; |
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294 | uint8_t proto; |
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295 | uint32_t remaining; |
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296 | uint32_t prev_rem; |
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297 | libtrace_tcp_t *tcp; |
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298 | libtrace_udp_t *udp; |
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299 | |
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300 | /* Start by finding the transport header */ |
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301 | transport = trace_get_transport(packet, &proto, &remaining); |
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302 | |
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303 | /* No transport header makes our life very easy - we can just return |
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304 | * zero */ |
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305 | if (transport == NULL) |
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306 | return trans_size; |
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307 | |
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308 | prev_rem = remaining; |
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309 | |
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310 | /* Skip past the transport header. Transport headers (at least the ones |
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311 | * we're interested in) can't be stacked so we only ever need to skip |
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312 | * past the one header */ |
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313 | |
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314 | /* Switch based on the protocol value set by trace_get_transport */ |
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315 | switch (proto) { |
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316 | case 6: /* TCP */ |
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317 | tcp = (libtrace_tcp_t *)transport; |
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318 | nexthdr = trace_get_payload_from_tcp(tcp, &remaining); |
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319 | break; |
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320 | case 17: /* UDP */ |
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321 | udp = (libtrace_udp_t *)transport; |
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322 | nexthdr = trace_get_payload_from_udp(udp, &remaining); |
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323 | break; |
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324 | default: |
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325 | /* We have no interest in ICMP, GRE etc, and we |
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326 | * should never have entered this function if the |
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327 | * packet is using those protocols anyway! */ |
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328 | fprintf(stderr, "Unexpected protocol: %u\n", proto); |
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329 | return 0; |
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330 | } |
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331 | |
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332 | /* If we don't have any post-transport payload, just return the |
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333 | * transport header size */ |
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334 | if (!nexthdr) |
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335 | return trans_size; |
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336 | |
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337 | /* Determine how many bytes we just skipped over and add it to the |
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338 | * total transport size */ |
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339 | assert(prev_rem >= remaining); |
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340 | trans_size += (prev_rem - remaining); |
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341 | |
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342 | /* Return the total size */ |
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343 | return trans_size; |
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344 | } |
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345 | |
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346 | static uint64_t calc_header_size(libtrace_packet_t *packet, demo_proto_t *proto) { |
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347 | |
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348 | uint64_t size = 0; |
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349 | |
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350 | /* Start with any meta-data headers */ |
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351 | size += calc_meta_size(packet); |
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352 | |
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353 | /* Work out the size of link layer headers */ |
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354 | size += calc_link_size(packet); |
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355 | |
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356 | /* Determine the size of the IP headers */ |
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357 | size += calc_ip_size(packet, proto); |
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358 | |
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359 | /* If the previous function call determined we were not an IP packet, |
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360 | * we can drop out now and return the current size */ |
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361 | if (*proto == DEMO_PROTO_NOTIP) |
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362 | return size; |
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363 | |
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364 | /* We can also drop out if the packet is not using a protocol that we |
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365 | * are interested in */ |
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366 | if (*proto == DEMO_PROTO_OTHER || *proto == DEMO_PROTO_UNKNOWN) |
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367 | return 0; |
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368 | |
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369 | /* Add on the transport headers */ |
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370 | size += calc_transport_size(packet); |
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371 | |
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372 | /* Return the total amount of headers */ |
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373 | return size; |
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374 | } |
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375 | |
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376 | static uint64_t calc_payload_size(libtrace_packet_t *packet, demo_proto_t proto) |
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377 | { |
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378 | |
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379 | uint64_t ip_plen = 0; |
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380 | uint64_t headers = 0; |
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381 | |
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382 | void *layer3; |
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383 | uint16_t ethertype; |
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384 | uint32_t remaining; |
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385 | |
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386 | layer3 = trace_get_layer3(packet, ðertype, &remaining); |
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387 | |
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388 | /* This should NEVER happen, but it's a good habit to check it anyway */ |
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389 | if (layer3 == NULL) |
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390 | return 0; |
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391 | |
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392 | /* Find the payload length in the IP header |
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393 | * |
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394 | * We also determine the size of the IP header (again!) as the payload |
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395 | * length includes the IP and transport headers */ |
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396 | |
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397 | if (ethertype == 0x0800) { /* IPv4 header */ |
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398 | libtrace_ip_t *ip = (libtrace_ip_t *)layer3; |
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399 | |
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400 | /* Remember to byte swap! */ |
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401 | ip_plen = ntohs(ip->ip_len); |
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402 | /* This value is only 4 bits so byteswapping is unnecessary */ |
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403 | headers += (4 * ip->ip_hl); |
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404 | |
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405 | |
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406 | } else if (ethertype == 0x86DD) { /* IPv6 header */ |
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407 | libtrace_ip6_t *ip = (libtrace_ip6_t *)layer3; |
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408 | |
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409 | /* Remember to byte swap! */ |
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410 | ip_plen = ntohs(ip->plen); |
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411 | /* IPv6 does not have a variable length header */ |
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412 | headers += sizeof(libtrace_ip6_t); |
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413 | |
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414 | |
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415 | } else { |
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416 | /* Not an IP packet - this should also never happen */ |
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417 | return 0; |
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418 | } |
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419 | |
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420 | |
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421 | /* Now we need to subtract the size of the transport header from the |
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422 | * IP payload length. */ |
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423 | if (proto == DEMO_PROTO_TCP) { |
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424 | |
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425 | /* Determine the size of the TCP header so we can subtract |
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426 | * that from our total payload length */ |
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427 | |
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428 | /* Since I already know the protocol and only need to |
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429 | * access a single value inside the TCP header, I can use |
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430 | * the trace_get_tcp() helper function instead of the more |
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431 | * verbose trace_get_transport() . */ |
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432 | libtrace_tcp_t *tcp = trace_get_tcp(packet); |
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433 | if (tcp == NULL) |
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434 | return 0; |
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435 | |
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436 | /* Again, byteswapping not required because the doff field is |
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437 | * only a single byte in size*/ |
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438 | headers += (tcp->doff * 4); |
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439 | } |
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440 | |
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441 | if (proto == DEMO_PROTO_UDP) { |
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442 | /* UDP has a fixed length header so we don't even need to use |
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443 | * trace_get_udp() */ |
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444 | headers += sizeof(libtrace_udp_t); |
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445 | } |
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446 | |
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447 | assert(headers <= ip_plen); |
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448 | |
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449 | /* Subtract the length of the IP and transport headers from the |
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450 | * payload length contained within the IP header */ |
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451 | return ip_plen - headers; |
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452 | |
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453 | } |
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454 | |
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455 | static void per_packet(libtrace_packet_t *packet) |
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456 | { |
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457 | uint64_t header_size = 0; |
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458 | uint64_t payload_size = 0; |
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459 | demo_proto_t protocol = DEMO_PROTO_UNKNOWN; |
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460 | |
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461 | /* Check if we're due to report some stats */ |
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462 | check_report(packet); |
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463 | |
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464 | /* We need to determine the amount of header in this packet */ |
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465 | header_size = calc_header_size(packet, &protocol); |
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466 | |
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467 | /* Now determine the payload size, if necessary */ |
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468 | if (protocol == DEMO_PROTO_TCP || protocol == DEMO_PROTO_UDP) { |
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469 | payload_size = calc_payload_size(packet, protocol); |
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470 | } |
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471 | |
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472 | /* Update the appropriate counters */ |
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473 | switch(protocol) { |
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474 | case DEMO_PROTO_TCP: |
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475 | tcp_header += header_size; |
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476 | tcp_payload += payload_size; |
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477 | break; |
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478 | |
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479 | case DEMO_PROTO_UDP: |
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480 | udp_header += header_size; |
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481 | udp_payload += payload_size; |
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482 | break; |
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483 | |
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484 | case DEMO_PROTO_NOTIP: |
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485 | not_ip += header_size; |
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486 | break; |
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487 | |
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488 | case DEMO_PROTO_OTHER: |
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489 | break; |
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490 | |
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491 | case DEMO_PROTO_UNKNOWN: |
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492 | break; |
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493 | } |
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494 | |
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495 | |
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496 | } |
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497 | |
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498 | /* Due to the amount of error checking required in our main function, it |
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499 | * is a lot simpler and tidier to place all the calls to various libtrace |
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500 | * destroy functions into a separate function. |
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501 | */ |
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502 | static void libtrace_cleanup(libtrace_t *trace, libtrace_packet_t *packet, |
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503 | libtrace_filter_t *filter) { |
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504 | |
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505 | /* It's very important to ensure that we aren't trying to destroy |
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506 | * a NULL structure, so each of the destroy calls will only occur |
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507 | * if the structure exists */ |
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508 | if (trace) |
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509 | trace_destroy(trace); |
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510 | |
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511 | if (packet) |
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512 | trace_destroy_packet(packet); |
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513 | |
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514 | if (filter) |
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515 | trace_destroy_filter(filter); |
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516 | } |
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517 | |
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518 | static void usage(char *prog) { |
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519 | fprintf(stderr, "Usage: %s [-i interval] [-f filter] inputURI\n", |
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520 | prog); |
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521 | } |
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522 | |
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523 | |
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524 | int main(int argc, char *argv[]) |
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525 | { |
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526 | libtrace_t *trace = NULL; |
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527 | libtrace_packet_t *packet = NULL; |
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528 | libtrace_filter_t *filter = NULL; |
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529 | |
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530 | int opt; |
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531 | char *filterstring = NULL; |
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532 | |
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533 | /* Ensure we have at least one argument after the program name */ |
---|
534 | if (argc < 2) { |
---|
535 | usage(argv[0]); |
---|
536 | return 1; |
---|
537 | } |
---|
538 | |
---|
539 | /* Using getopt to handle any command line flags that would set the |
---|
540 | * reporting interval and a filter */ |
---|
541 | while ((opt = getopt(argc, argv, "i:f:")) != EOF) { |
---|
542 | switch (opt) { |
---|
543 | case 'i': |
---|
544 | interval = atoi(optarg); |
---|
545 | break; |
---|
546 | case 'f': |
---|
547 | filterstring = optarg; |
---|
548 | break; |
---|
549 | default: |
---|
550 | usage(argv[0]); |
---|
551 | return 1; |
---|
552 | } |
---|
553 | } |
---|
554 | |
---|
555 | /* After processing the options, we still need an argument to define |
---|
556 | * the input URI */ |
---|
557 | if (optind + 1 > argc) { |
---|
558 | usage(argv[0]); |
---|
559 | return 1; |
---|
560 | } |
---|
561 | |
---|
562 | /* Create the filter if a filter string was provided */ |
---|
563 | if (filterstring != NULL) { |
---|
564 | filter = trace_create_filter(filterstring); |
---|
565 | if (filter == NULL) { |
---|
566 | fprintf(stderr, "Failed to create filter (%s)\n", |
---|
567 | filterstring); |
---|
568 | libtrace_cleanup(trace, packet, filter); |
---|
569 | return 1; |
---|
570 | } |
---|
571 | } |
---|
572 | |
---|
573 | /* Creating and initialising a packet structure to store the packets |
---|
574 | * that we're going to read from the trace */ |
---|
575 | packet = trace_create_packet(); |
---|
576 | |
---|
577 | if (packet == NULL) { |
---|
578 | /* Unfortunately, trace_create_packet doesn't use the libtrace |
---|
579 | * error system. This is because libtrace errors are associated |
---|
580 | * with the trace structure, not the packet. In our case, we |
---|
581 | * haven't even created a trace at this point so we can't |
---|
582 | * really expect libtrace to set an error on it for us, can |
---|
583 | * we? |
---|
584 | */ |
---|
585 | perror("Creating libtrace packet"); |
---|
586 | libtrace_cleanup(trace, packet, filter); |
---|
587 | return 1; |
---|
588 | } |
---|
589 | |
---|
590 | /* Opening and starting the input trace. Note that unlike the other |
---|
591 | * examples, we can't just use argv[1] as we may have seen command |
---|
592 | * line options. Instead we should use optind which will be set to |
---|
593 | * the index of the first non-getopt argument */ |
---|
594 | trace = trace_create(argv[optind]); |
---|
595 | |
---|
596 | if (trace_is_err(trace)) { |
---|
597 | trace_perror(trace,"Opening trace file"); |
---|
598 | libtrace_cleanup(trace, packet, filter); |
---|
599 | return 1; |
---|
600 | } |
---|
601 | |
---|
602 | /* Apply a filter, if one was created */ |
---|
603 | if (filter != NULL) { |
---|
604 | if (trace_config(trace, TRACE_OPTION_FILTER, filter) == -1) { |
---|
605 | trace_perror(trace, "Configuring filter"); |
---|
606 | libtrace_cleanup(trace, packet, filter); |
---|
607 | return 1; |
---|
608 | } |
---|
609 | } |
---|
610 | |
---|
611 | if (trace_start(trace) == -1) { |
---|
612 | trace_perror(trace,"Starting trace"); |
---|
613 | libtrace_cleanup(trace, packet, filter); |
---|
614 | return 1; |
---|
615 | } |
---|
616 | |
---|
617 | /* This loop will read packets from the trace until either EOF is |
---|
618 | * reached or an error occurs (hopefully the former!) |
---|
619 | * |
---|
620 | * Remember, EOF will return 0 so we only want to continue looping |
---|
621 | * as long as the return value is greater than zero |
---|
622 | */ |
---|
623 | while (trace_read_packet(trace,packet)>0) { |
---|
624 | /* Call our per_packet function for every packet */ |
---|
625 | per_packet(packet); |
---|
626 | } |
---|
627 | |
---|
628 | /* If the trace is in an error state, then we know that we fell out of |
---|
629 | * the above loop because an error occurred rather than EOF being |
---|
630 | * reached. Therefore, we should probably tell the user that something |
---|
631 | * went wrong |
---|
632 | */ |
---|
633 | if (trace_is_err(trace)) { |
---|
634 | trace_perror(trace,"Reading packets"); |
---|
635 | libtrace_cleanup(trace, packet, filter); |
---|
636 | return 1; |
---|
637 | } |
---|
638 | |
---|
639 | /* Print out the contents of the counters before exiting */ |
---|
640 | print_stats(); |
---|
641 | |
---|
642 | libtrace_cleanup(trace, packet, filter); |
---|
643 | |
---|
644 | return 0; |
---|
645 | } |
---|