66 lines
1 KiB
C
66 lines
1 KiB
C
#include <arpa/inet.h>
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#include <unistd.h>
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#include <stdint.h>
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#include <string.h>
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#include <stdlib.h>
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#include <stdio.h>
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enum tftp_opcode {
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RRQ = 1,
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WRQ = 2,
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DATA = 3,
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ACK = 4,
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ERR = 5,
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OACK = 6
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};
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static inline char *pkt_mknum(char *pkt, uint16_t n)
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{
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*(uint16_t*)pkt = htons(n);
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return pkt + 2;
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}
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static char *pkt_mkopt(char *pkt, const char *opt, const char* val)
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{
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strcpy(pkt, opt);
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pkt += strlen(opt) + 1;
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strcpy(pkt, val);
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pkt += strlen(val) + 1;
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return pkt;
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}
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int main(int argc, char** argv)
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{
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if (argc != 2) {
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return 1;
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}
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const size_t fsize = 4096;
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char pkt[1024 + 4];
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char* p;
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size_t len = 512;
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memset(pkt, 0, sizeof(pkt));
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if (argc == 2 && argv[1][0] == 'k') {
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len = 1024;
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p = pkt_mknum(pkt, OACK);
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pkt_mkopt(p, "blksize", "1024");
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} else {
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p = pkt_mknum(pkt, ACK);
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pkt_mknum(p, 0);
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}
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write(STDOUT_FILENO, pkt, len + 4);
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size_t i = 0;
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for (; i < (fsize/len + 1); ++i) {
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memset(pkt, 0, sizeof(pkt));
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p = pkt_mknum(pkt, ACK);
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pkt_mknum(p, i + 1);
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write(STDOUT_FILENO, pkt, len + 4);
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}
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}
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