1*49a6e16fSderaadt /* $OpenBSD: mmap-sysctl-copyin.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.always_keepalive"
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_ALWAYS_KEEPALIVE };
3201bde78aSbluhm u_int miblen = sizeof(mib) / sizeof(mib[0]);
3301bde78aSbluhm int fd, val;
3401bde78aSbluhm size_t len;
3501bde78aSbluhm
3601bde78aSbluhm /*
3701bde78aSbluhm * Get current value of sysctl net.inet.tcp.always_keepalive
3801bde78aSbluhm * and write it into a file on the NFS server.
3901bde78aSbluhm */
4001bde78aSbluhm snprintf(path, sizeof(path), "%s/%s", SERVER, FILE);
4101bde78aSbluhm if ((fd = open(path, O_WRONLY|O_CREAT|O_TRUNC, 0777)) == -1)
4201bde78aSbluhm err(1, "open write '%s'", path);
4301bde78aSbluhm len = sizeof(int);
4401bde78aSbluhm if (sysctl(mib, miblen, &val, &len, NULL, 0) == -1)
4501bde78aSbluhm err(1, "sysctl get keepalive");
4601bde78aSbluhm if (len != sizeof(int))
4701bde78aSbluhm errx(1, "len is not %zu: %zu", sizeof(int), len);
4801bde78aSbluhm if (write(fd, &val, len) == -1)
4901bde78aSbluhm err(1, "write");
5001bde78aSbluhm if (close(fd) == -1)
5101bde78aSbluhm err(1, "close write");
5201bde78aSbluhm
5301bde78aSbluhm /*
5401bde78aSbluhm * Map file on NFS client and read value to
5501bde78aSbluhm * sysctl net.inet.tcp.always_keepalive.
5601bde78aSbluhm */
5701bde78aSbluhm snprintf(path, sizeof(path), "%s/%s", CLIENT, FILE);
5801bde78aSbluhm if ((fd = open(path, O_RDWR)) == -1)
5901bde78aSbluhm err(1, "open mmap '%s'", path);
6001bde78aSbluhm p = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
6101bde78aSbluhm if (p == MAP_FAILED)
6201bde78aSbluhm err(1, "mmap");
6301bde78aSbluhm if (sysctl(mib, miblen, NULL, 0, p, sizeof(int)) == -1)
6401bde78aSbluhm err(1, "sysctl set keepalive");
6501bde78aSbluhm if (close(fd) == -1)
6601bde78aSbluhm err(1, "close mmap");
6701bde78aSbluhm
6801bde78aSbluhm return (0);
6901bde78aSbluhm }
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