1 /*
2 * Copyright 2016, The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 // Simple program to try running an APF program against a packet.
18
19 #include <libgen.h>
20 #include <stdint.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24
25 #include "apf_interpreter.h"
26
27 // Parses hex in "input". Allocates and fills "*output" with parsed bytes.
28 // Returns length in bytes of "*output".
parse_hex(char * input,uint8_t ** output)29 int parse_hex(char* input, uint8_t** output) {
30 int length = strlen(input);
31 if (length & 1) {
32 fprintf(stderr, "Argument not even number of characters: %s\n", input);
33 exit(1);
34 }
35 length >>= 1;
36 *output = malloc(length);
37 if (*output == NULL) {
38 fprintf(stderr, "Out of memory, tried to allocate %d\n", length);
39 exit(1);
40 }
41 for (int i = 0; i < length; i++) {
42 char byte[3] = { input[i*2], input[i*2+1], 0 };
43 char* end_ptr;
44 (*output)[i] = strtol(byte, &end_ptr, 16);
45 if (end_ptr != byte + 2) {
46 fprintf(stderr, "Failed to parse hex %s\n", byte);
47 exit(1);
48 }
49 }
50 return length;
51 }
52
print_hex(uint8_t * input,int len)53 void print_hex(uint8_t* input, int len) {
54 for (int i = 0; i < len; ++i) {
55 printf("%02x", input[i]);
56 }
57 }
58
main(int argc,char * argv[])59 int main(int argc, char* argv[]) {
60 if (argc < 3 || argc > 5) {
61 fprintf(stderr,
62 "Usage: %s <program> <packet> [<data>] [<age>]\n"
63 " program: APF program, in hex\n"
64 " packet: Packet to run through program, in hex\n"
65 " data: Data memory contents, in hex\n"
66 " age: Age of program in seconds (default: 0)\n",
67 basename(argv[0]));
68 exit(1);
69 }
70 uint8_t* program;
71 uint32_t program_len = parse_hex(argv[1], &program);
72 uint8_t* packet;
73 uint32_t packet_len = parse_hex(argv[2], &packet);
74 uint8_t* data = NULL;
75 uint32_t data_len = argc > 3 ? parse_hex(argv[3], &data) : 0;
76 uint32_t filter_age = argc > 4 ? atoi(argv[4]) : 0;
77
78 // Combine the program and data into the unified APF buffer.
79 if (data) {
80 program = realloc(program, program_len + data_len);
81 memcpy(program + program_len, data, data_len);
82 free(data);
83 }
84
85 uint32_t ram_len = program_len + data_len;
86 int ret = accept_packet(program, program_len, ram_len, packet, packet_len,
87 filter_age);
88 printf("Packet %sed\n", ret ? "pass" : "dropp");
89 if (data_len) {
90 printf("Data: ");
91 print_hex(program + program_len, data_len);
92 printf("\n");
93 }
94 free(program);
95 free(packet);
96 return ret;
97 }
98