1*49a6e16fSderaadt /* $OpenBSD: mmap-sysctl-copyout.c,v 1.3 2021/12/13 16:56:50 deraadt Exp $ */
27db0f3fbSbluhm
3*49a6e16fSderaadt #include <sys/types.h>
401bde78aSbluhm #include <sys/mman.h>
501bde78aSbluhm #include <sys/queue.h>
601bde78aSbluhm #include <sys/socket.h>
701bde78aSbluhm #include <sys/sysctl.h>
801bde78aSbluhm
901bde78aSbluhm #include <netinet/in.h>
1001bde78aSbluhm #include <netinet/tcp.h>
1101bde78aSbluhm #include <netinet/tcp_seq.h>
1201bde78aSbluhm #include <netinet/tcp_timer.h>
1301bde78aSbluhm #include <netinet/tcp_var.h>
1401bde78aSbluhm
1501bde78aSbluhm #include <err.h>
1601bde78aSbluhm #include <fcntl.h>
1701bde78aSbluhm #include <stdlib.h>
18*49a6e16fSderaadt #include <limits.h>
1901bde78aSbluhm #include <stdio.h>
2001bde78aSbluhm #include <string.h>
2101bde78aSbluhm #include <unistd.h>
2201bde78aSbluhm
2301bde78aSbluhm #define FILE "sysctl-net.inet.tcp.stats"
247db0f3fbSbluhm #define CLIENT "/mnt/regress-nfs-client"
257db0f3fbSbluhm #define SERVER "/mnt/regress-nfs-server"
2601bde78aSbluhm
2701bde78aSbluhm int
main(void)2801bde78aSbluhm main(void)
2901bde78aSbluhm {
3001bde78aSbluhm char *p, path[PATH_MAX];
3101bde78aSbluhm int mib[] = { CTL_NET, PF_INET, IPPROTO_TCP, TCPCTL_STATS };
3201bde78aSbluhm u_int miblen = sizeof(mib) / sizeof(mib[0]);
3301bde78aSbluhm struct tcpstat stats;
3401bde78aSbluhm int fd;
3501bde78aSbluhm size_t len;
3601bde78aSbluhm ssize_t n;
3701bde78aSbluhm
3801bde78aSbluhm /*
3901bde78aSbluhm * Initialize file on NFS server.
4001bde78aSbluhm */
4101bde78aSbluhm snprintf(path, sizeof(path), "%s/%s", SERVER, FILE);
4201bde78aSbluhm if ((fd = open(path, O_RDWR|O_CREAT|O_TRUNC, 0777)) == -1)
4301bde78aSbluhm err(1, "open write '%s'", path);
4401bde78aSbluhm len = sizeof(struct tcpstat);
4501bde78aSbluhm memset(&stats, 0, len);
4601bde78aSbluhm if ((n = write(fd, &stats, len)) == -1)
4701bde78aSbluhm err(1, "write");
4801bde78aSbluhm if ((size_t)n != len)
4901bde78aSbluhm errx(1, "write not %zu: %zd", len, n);
5001bde78aSbluhm if (close(fd) == -1)
5101bde78aSbluhm err(1, "close read");
5201bde78aSbluhm
5301bde78aSbluhm /*
5401bde78aSbluhm * Map file on NFS client and write sysctl net.inet.tcp.stats into it.
5501bde78aSbluhm */
5601bde78aSbluhm snprintf(path, sizeof(path), "%s/%s", CLIENT, FILE);
5701bde78aSbluhm if ((fd = open(path, O_RDWR)) == -1)
5801bde78aSbluhm err(1, "open mmap '%s'", path);
5901bde78aSbluhm p = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
6001bde78aSbluhm if (p == MAP_FAILED)
6101bde78aSbluhm err(1, "mmap");
6201bde78aSbluhm if (sysctl(mib, miblen, p, &len, NULL, 0) == -1)
6301bde78aSbluhm err(1, "sysctl get stat");
6401bde78aSbluhm if (len != sizeof(struct tcpstat))
6501bde78aSbluhm errx(1, "len not %zu: %zu", sizeof(struct tcpstat), len);
6601bde78aSbluhm if (close(fd) == -1)
6701bde78aSbluhm err(1, "close mmap");
6801bde78aSbluhm
6901bde78aSbluhm /*
7001bde78aSbluhm * Read file from NFS server.
7101bde78aSbluhm */
7201bde78aSbluhm snprintf(path, sizeof(path), "%s/%s", SERVER, FILE);
7301bde78aSbluhm if ((fd = open(path, O_RDONLY)) == -1)
7401bde78aSbluhm err(1, "open read '%s'", path);
7501bde78aSbluhm if ((n = read(fd, &stats, len)) == -1)
7601bde78aSbluhm err(1, "read");
7701bde78aSbluhm if ((size_t)n != len)
7801bde78aSbluhm errx(1, "read not %zu: %zd", len, n);
7901bde78aSbluhm if (close(fd) == -1)
8001bde78aSbluhm err(1, "close read");
8101bde78aSbluhm
8201bde78aSbluhm return (0);
8301bde78aSbluhm }
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