[PATCH v6] tests: extend for decoding of udev_monitor_netlink_header

[Harsha Sharma]

On Sun, Apr 8, 2018 at 5:30 PM, Harsha Sharma
<harshasharmaiitr at gmail.com> wrote:
> * tests/netlink_kobject_uevent.c: Add test_nlmsg_type_udev.
> ---
> Changes in v6:
> * invoke sprintrc before printf call in existing testcases
> * change argument of print_quoted_memory to DEFAULT_STRLEN
> * Add case for len == offset

Code coverage is 100 % now for netlink_kobject_uevent.c.
(https://codecov.io/gh/hs256/strace/src/HarshaSharma%2FNETLINK_KOBJECT_UEVENT/netlink_kobject_uevent.c).
Thanks for your time.

> Changes in v5:
> * invoke sprintrc before first printf call
>
> Changes in v4:
> * invoke sprintrc before first printf call
> * minor fix
>
> Changes in v3:
> * change format type
>
> Changes in v2:
> * Add decoding of kernel messages
> * initialize udev_monitor_netlink_header with non-zero values
> * cover case for length exceeding size of structure
>
>  tests/netlink_kobject_uevent.c | 92 +++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 90 insertions(+), 2 deletions(-)
>
> diff --git a/tests/netlink_kobject_uevent.c b/tests/netlink_kobject_uevent.c
> index cacab5fd..2c83324c 100644
> --- a/tests/netlink_kobject_uevent.c
> +++ b/tests/netlink_kobject_uevent.c
> @@ -27,9 +27,92 @@
>   */
>
>  #include "tests.h"
> +#include <string.h>
>  #include <stdio.h>
>  #include <sys/socket.h>
> +#include <arpa/inet.h>
>  #include "netlink.h"
> +#include "netlink_kobject_uevent.h"
> +
> +static void
> +test_nlmsg_type_udev(const int fd)
> +{
> +       long ret;
> +       const char *err_rc;
> +       unsigned int offset = 8;
> +       struct udev_monitor_netlink_header uh = {
> +               .prefix = "libudev",
> +               .magic = htonl(0xfeedcafe),
> +               .header_size = sizeof(uh),
> +               .properties_off = 40,
> +               .properties_len = 299,
> +               .filter_subsystem_hash = htonl(0xc370b302),
> +               .filter_devtype_hash = htonl(0x10800000),
> +               .filter_tag_bloom_hi = htonl(0x2000400),
> +               .filter_tag_bloom_lo = htonl(0x10800000),
> +       };
> +       unsigned int len = sizeof(uh);
> +       char buf[len + offset];
> +       memcpy(buf, &uh, len);
> +       memcpy(buf + len, "12345678", offset);
> +
> +       ret = sendto(fd, &uh, len, MSG_DONTWAIT, NULL, 0);
> +       err_rc = sprintrc(ret);
> +       printf("sendto(%d, {{prefix=\"%s\", magic=htonl(%#x)"
> +              ", header_size=%u, properties_off=%u, properties_len=%u"
> +              ", filter_subsystem_hash=htonl(%#x)"
> +              ", filter_devtype_hash=htonl(%#x)"
> +              ", filter_tag_bloom_hi=htonl(%#x)"
> +              ", filter_tag_bloom_lo=htonl(%#x)}}, %u, MSG_DONTWAIT, NULL, "
> +              "0) = %s\n"
> +              , fd, uh.prefix,
> +              ntohl(uh.magic), uh.header_size, uh.properties_off,
> +              uh.properties_len, ntohl(uh.filter_subsystem_hash),
> +              ntohl(uh.filter_devtype_hash), ntohl(uh.filter_tag_bloom_hi),
> +              ntohl(uh.filter_tag_bloom_lo), len, err_rc);
> +
> +       ret = sendto(fd, &buf, len + offset, MSG_DONTWAIT, NULL, 0);
> +       err_rc = sprintrc(ret);
> +       printf("sendto(%d, {{prefix=\"%s\", magic=htonl(%#x)"
> +              ", header_size=%u, properties_off=%u, properties_len=%u"
> +              ", filter_subsystem_hash=htonl(%#x)"
> +              ", filter_devtype_hash=htonl(%#x)"
> +              ", filter_tag_bloom_hi=htonl(%#x)"
> +              ", filter_tag_bloom_lo=htonl(%#x)}, "
> +              , fd, uh.prefix,
> +              ntohl(uh.magic), uh.header_size, uh.properties_off,
> +              uh.properties_len, ntohl(uh.filter_subsystem_hash),
> +              ntohl(uh.filter_devtype_hash), ntohl(uh.filter_tag_bloom_hi),
> +              ntohl(uh.filter_tag_bloom_lo));
> +       print_quoted_memory(buf + len, offset);
> +       printf("}, %u, MSG_DONTWAIT, NULL, 0) = %s\n",
> +              len + offset, err_rc);
> +
> +}
> +
> +static void
> +test_nlmsg_type_kernel(const int fd)
> +{
> +       long ret;
> +       const char *err_rc;
> +       struct udev_monitor_netlink_header uh = {
> +               .prefix = "change@",
> +               .magic = htonl(0xfeedcafe),
> +               .header_size = sizeof(uh),
> +               .properties_off = 10,
> +               .properties_len = 299,
> +               .filter_subsystem_hash = htonl(0xfffffff),
> +               .filter_devtype_hash = htonl(0x10000000),
> +               .filter_tag_bloom_hi = htonl(0x2000400),
> +       };
> +
> +       ret = sendto(fd, &uh, sizeof(uh), MSG_DONTWAIT, NULL, 0);
> +       err_rc = sprintrc(ret);
> +       printf("sendto(%d, ", fd);
> +       print_quoted_memory(&uh, DEFAULT_STRLEN);
> +       printf("..., %u, MSG_DONTWAIT, NULL, 0) = %s\n",
> +              (unsigned) sizeof(uh), err_rc);
> +}
>
>  int
>  main(void)
> @@ -37,24 +120,29 @@ main(void)
>         skip_if_unavailable("/proc/self/fd/");
>
>         long rc;
> +       const char *err_rc;
>         int fd = create_nl_socket(NETLINK_KOBJECT_UEVENT);
>
> +       test_nlmsg_type_udev(fd);
> +       test_nlmsg_type_kernel(fd);
>         /* test using data that looks like a zero-length C string */
>         char *const buf = tail_alloc(DEFAULT_STRLEN + 1);
>         buf[0] = '=';
>         fill_memory_ex(buf + 1, DEFAULT_STRLEN, 0, DEFAULT_STRLEN);
>
>         rc = sendto(fd, buf + 1, DEFAULT_STRLEN, MSG_DONTWAIT, NULL, 0);
> +       err_rc = sprintrc(rc);
>         printf("sendto(%d, ", fd);
>         print_quoted_memory(buf + 1, DEFAULT_STRLEN);
>         printf(", %u, MSG_DONTWAIT, NULL, 0) = %s\n",
> -              DEFAULT_STRLEN, sprintrc(rc));
> +              DEFAULT_STRLEN, err_rc);
>
>         rc = sendto(fd, buf, DEFAULT_STRLEN + 1, MSG_DONTWAIT, NULL, 0);
> +       err_rc = sprintrc(rc);
>         printf("sendto(%d, ", fd);
>         print_quoted_memory(buf, DEFAULT_STRLEN);
>         printf("..., %u, MSG_DONTWAIT, NULL, 0) = %s\n",
> -              DEFAULT_STRLEN + 1, sprintrc(rc));
> +              DEFAULT_STRLEN + 1, err_rc);
>
>         puts("+++ exited with 0 +++");
>         return 0;
> --
> 2.14.1
>