| Message ID | 20211122112205.16752-2-fw@strlen.de (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Delegated to: | Matthieu Baerts |
| Headers | show |
| Series | [mptcp-next,1/2] mptcp: getsockopt: add support for IP_TOS | expand |
On 22/11/2021 12:22, Florian Westphal wrote: > Check that getsockopt(IP_TOS) returns what setsockopt(IP_TOS) did set > right before. Thank you for adding the new selftest! > +static void init_rng(void) That's really a detail but this function in the other MPTCP selftests always intrigued me. Do you mind me asking a few questions about it? :) > +{ > + int fd = open("/dev/urandom", O_RDONLY); > + unsigned int foo; > + > + if (fd > 0) { - Here, we do more if 'open()' succeeds or fails (0 is still a valid fd). I guess it is unlikely to have 0 here because we don't close fd 0 elsewhere if I'm not mistaken. - if open() "fails", 'foo' will be used later while undefined. Which is fine in this context but static code analysers might complain. > + int ret = read(fd, &foo, sizeof(foo)); > + > + if (ret < 0) > + srand(fd + foo); - Here we do this if 'read()' fails with an undefined 'foo'. Again it is fine in this context but strange :) > + close(fd); - should not happen: the 'fd' might not be closed if fd == 0. > + } > + > + srand(foo); The function looks strange but I don't see issue in this context. Anyway, why did we not use the typical: srand(time(NULL)) Cheers, Matt
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c index 417b11cafafe..87ed6d050e67 100644 --- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c +++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c @@ -4,6 +4,7 @@ #include <assert.h> #include <errno.h> +#include <fcntl.h> #include <limits.h> #include <string.h> #include <stdarg.h> @@ -594,6 +595,30 @@ static int server(int pipefd) return 0; } +static void test_ip_tos_sockopt(int fd) +{ + uint8_t tos_in, tos_out; + socklen_t s; + int r; + + tos_in = rand() & 0xfc; + r = setsockopt(fd, SOL_IP, IP_TOS, &tos_in, sizeof(tos_out)); + if (r != 0) + die_perror("setsockopt IP_TOS"); + + tos_out = 0; + s = sizeof(tos_out); + r = getsockopt(fd, SOL_IP, IP_TOS, &tos_out, &s); + if (r != 0) + die_perror("getsockopt IP_TOS"); + + if (tos_in != tos_out) + xerror("tos %x != %x\n", tos_in, tos_out); + + if (s != 1) + xerror("tos should be 1 byte"); +} + static int client(int pipefd) { int fd = -1; @@ -611,6 +636,8 @@ static int client(int pipefd) xerror("Unknown pf %d\n", pf); } + test_ip_tos_sockopt(fd); + connect_one_server(fd, pipefd); return 0; @@ -642,6 +669,22 @@ static int rcheck(int wstatus, const char *what) return 111; } +static void init_rng(void) +{ + int fd = open("/dev/urandom", O_RDONLY); + unsigned int foo; + + if (fd > 0) { + int ret = read(fd, &foo, sizeof(foo)); + + if (ret < 0) + srand(fd + foo); + close(fd); + } + + srand(foo); +} + int main(int argc, char *argv[]) { int e1, e2, wstatus; @@ -650,6 +693,8 @@ int main(int argc, char *argv[]) parse_opts(argc, argv); + init_rng(); + e1 = pipe(pipefds); if (e1 < 0) die_perror("pipe");
Check that getsockopt(IP_TOS) returns what setsockopt(IP_TOS) did set right before. Signed-off-by: Florian Westphal <fw@strlen.de> --- .../selftests/net/mptcp/mptcp_sockopt.c | 45 +++++++++++++++++++ 1 file changed, 45 insertions(+)