| Message ID | 20240916122230.114800-3-matthieu@buffet.re (mailing list archive) |
|---|---|
| State | RFC |
| Headers | show |
| Series | landlock: Add UDP access control support | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch, async |
On Mon, Sep 16, 2024 at 02:22:25PM +0200, Matthieu Buffet wrote: > - Clarify which environment variables are optional, which ones are > mandatory > - Clarify the difference between unset variables and empty ones > - Move the (larger) help message to a helper function > > Signed-off-by: Matthieu Buffet <matthieu@buffet.re> > --- > samples/landlock/sandboxer.c | 86 ++++++++++++++++++++---------------- > 1 file changed, 48 insertions(+), 38 deletions(-) > > diff --git a/samples/landlock/sandboxer.c b/samples/landlock/sandboxer.c > index a84ae3a15482..08704504dc51 100644 > --- a/samples/landlock/sandboxer.c > +++ b/samples/landlock/sandboxer.c > @@ -221,6 +221,53 @@ static int populate_ruleset_net(const char *const env_var, const int ruleset_fd, > > #define LANDLOCK_ABI_LAST 5 > > +static void print_help(const char *prog) > +{ > + fprintf(stderr, > + "usage: %s=\"...\" %s=\"...\" [other environment variables] %s " > + "<cmd> [args]...\n\n", > + ENV_FS_RO_NAME, ENV_FS_RW_NAME, prog); > + fprintf(stderr, > + "Execute a command in a restricted environment.\n\n"); > + fprintf(stderr, > + "Environment variables containing paths and ports " > + "can be multi-valued, with a colon delimiter.\n" > + "\n" > + "Mandatory settings:\n"); > + fprintf(stderr, > + "* %s: list of paths allowed to be used in a read-only way.\n", > + ENV_FS_RO_NAME); > + fprintf(stderr, > + "* %s: list of paths allowed to be used in a read-write way.\n", > + ENV_FS_RW_NAME); > + fprintf(stderr, > + "\n" > + "Optional settings (when not set, their associated access " > + "check is always allowed) (for lists, an empty string means " > + "to allow nothing, e.g. %s=\"\"):\n", > + ENV_TCP_BIND_NAME); > + fprintf(stderr, > + "* %s: list of ports allowed to bind (server).\n", > + ENV_TCP_BIND_NAME); > + fprintf(stderr, > + "* %s: list of ports allowed to connect (client).\n", > + ENV_TCP_CONNECT_NAME); > + fprintf(stderr, > + "\n" > + "Example:\n" > + "%s=\"${PATH}:/lib:/usr:/proc:/etc:/dev/urandom\" " > + "%s=\"/dev/null:/dev/full:/dev/zero:/dev/pts:/tmp\" " > + "%s=\"9418\" " > + "%s=\"80:443\" " > + "%s bash -i\n\n", > + ENV_FS_RO_NAME, ENV_FS_RW_NAME, ENV_TCP_BIND_NAME, > + ENV_TCP_CONNECT_NAME, prog); > + fprintf(stderr, > + "This sandboxer can use Landlock features " > + "up to ABI version %d.\n", > + LANDLOCK_ABI_LAST); > +} > + > int main(const int argc, char *const argv[], char *const *const envp) > { > const char *cmd_path; > @@ -237,44 +284,7 @@ int main(const int argc, char *const argv[], char *const *const envp) > }; > > if (argc < 2) { > - fprintf(stderr, > - "usage: %s=\"...\" %s=\"...\" %s=\"...\" %s=\"...\"%s " > - "<cmd> [args]...\n\n", > - ENV_FS_RO_NAME, ENV_FS_RW_NAME, ENV_TCP_BIND_NAME, > - ENV_TCP_CONNECT_NAME, argv[0]); > - fprintf(stderr, > - "Execute a command in a restricted environment.\n\n"); > - fprintf(stderr, > - "Environment variables containing paths and ports " > - "each separated by a colon:\n"); > - fprintf(stderr, > - "* %s: list of paths allowed to be used in a read-only way.\n", > - ENV_FS_RO_NAME); > - fprintf(stderr, > - "* %s: list of paths allowed to be used in a read-write way.\n\n", > - ENV_FS_RW_NAME); > - fprintf(stderr, > - "Environment variables containing ports are optional " > - "and could be skipped.\n"); > - fprintf(stderr, > - "* %s: list of ports allowed to bind (server).\n", > - ENV_TCP_BIND_NAME); > - fprintf(stderr, > - "* %s: list of ports allowed to connect (client).\n", > - ENV_TCP_CONNECT_NAME); > - fprintf(stderr, > - "\nexample:\n" > - "%s=\"${PATH}:/lib:/usr:/proc:/etc:/dev/urandom\" " > - "%s=\"/dev/null:/dev/full:/dev/zero:/dev/pts:/tmp\" " > - "%s=\"9418\" " > - "%s=\"80:443\" " > - "%s bash -i\n\n", > - ENV_FS_RO_NAME, ENV_FS_RW_NAME, ENV_TCP_BIND_NAME, > - ENV_TCP_CONNECT_NAME, argv[0]); > - fprintf(stderr, > - "This sandboxer can use Landlock features " > - "up to ABI version %d.\n", > - LANDLOCK_ABI_LAST); > + print_help(argv[0]); Looks good, please rebase on my "next" branch with the new LL_SCOPED variable and send it in a new series along with the previous fix: https://git.kernel.org/pub/scm/linux/kernel/git/mic/linux.git/log/?h=next > return 1; > } > > -- > 2.39.5 > >
diff --git a/samples/landlock/sandboxer.c b/samples/landlock/sandboxer.c index a84ae3a15482..08704504dc51 100644 --- a/samples/landlock/sandboxer.c +++ b/samples/landlock/sandboxer.c @@ -221,6 +221,53 @@ static int populate_ruleset_net(const char *const env_var, const int ruleset_fd, #define LANDLOCK_ABI_LAST 5 +static void print_help(const char *prog) +{ + fprintf(stderr, + "usage: %s=\"...\" %s=\"...\" [other environment variables] %s " + "<cmd> [args]...\n\n", + ENV_FS_RO_NAME, ENV_FS_RW_NAME, prog); + fprintf(stderr, + "Execute a command in a restricted environment.\n\n"); + fprintf(stderr, + "Environment variables containing paths and ports " + "can be multi-valued, with a colon delimiter.\n" + "\n" + "Mandatory settings:\n"); + fprintf(stderr, + "* %s: list of paths allowed to be used in a read-only way.\n", + ENV_FS_RO_NAME); + fprintf(stderr, + "* %s: list of paths allowed to be used in a read-write way.\n", + ENV_FS_RW_NAME); + fprintf(stderr, + "\n" + "Optional settings (when not set, their associated access " + "check is always allowed) (for lists, an empty string means " + "to allow nothing, e.g. %s=\"\"):\n", + ENV_TCP_BIND_NAME); + fprintf(stderr, + "* %s: list of ports allowed to bind (server).\n", + ENV_TCP_BIND_NAME); + fprintf(stderr, + "* %s: list of ports allowed to connect (client).\n", + ENV_TCP_CONNECT_NAME); + fprintf(stderr, + "\n" + "Example:\n" + "%s=\"${PATH}:/lib:/usr:/proc:/etc:/dev/urandom\" " + "%s=\"/dev/null:/dev/full:/dev/zero:/dev/pts:/tmp\" " + "%s=\"9418\" " + "%s=\"80:443\" " + "%s bash -i\n\n", + ENV_FS_RO_NAME, ENV_FS_RW_NAME, ENV_TCP_BIND_NAME, + ENV_TCP_CONNECT_NAME, prog); + fprintf(stderr, + "This sandboxer can use Landlock features " + "up to ABI version %d.\n", + LANDLOCK_ABI_LAST); +} + int main(const int argc, char *const argv[], char *const *const envp) { const char *cmd_path; @@ -237,44 +284,7 @@ int main(const int argc, char *const argv[], char *const *const envp) }; if (argc < 2) { - fprintf(stderr, - "usage: %s=\"...\" %s=\"...\" %s=\"...\" %s=\"...\"%s " - "<cmd> [args]...\n\n", - ENV_FS_RO_NAME, ENV_FS_RW_NAME, ENV_TCP_BIND_NAME, - ENV_TCP_CONNECT_NAME, argv[0]); - fprintf(stderr, - "Execute a command in a restricted environment.\n\n"); - fprintf(stderr, - "Environment variables containing paths and ports " - "each separated by a colon:\n"); - fprintf(stderr, - "* %s: list of paths allowed to be used in a read-only way.\n", - ENV_FS_RO_NAME); - fprintf(stderr, - "* %s: list of paths allowed to be used in a read-write way.\n\n", - ENV_FS_RW_NAME); - fprintf(stderr, - "Environment variables containing ports are optional " - "and could be skipped.\n"); - fprintf(stderr, - "* %s: list of ports allowed to bind (server).\n", - ENV_TCP_BIND_NAME); - fprintf(stderr, - "* %s: list of ports allowed to connect (client).\n", - ENV_TCP_CONNECT_NAME); - fprintf(stderr, - "\nexample:\n" - "%s=\"${PATH}:/lib:/usr:/proc:/etc:/dev/urandom\" " - "%s=\"/dev/null:/dev/full:/dev/zero:/dev/pts:/tmp\" " - "%s=\"9418\" " - "%s=\"80:443\" " - "%s bash -i\n\n", - ENV_FS_RO_NAME, ENV_FS_RW_NAME, ENV_TCP_BIND_NAME, - ENV_TCP_CONNECT_NAME, argv[0]); - fprintf(stderr, - "This sandboxer can use Landlock features " - "up to ABI version %d.\n", - LANDLOCK_ABI_LAST); + print_help(argv[0]); return 1; }
- Clarify which environment variables are optional, which ones are mandatory - Clarify the difference between unset variables and empty ones - Move the (larger) help message to a helper function Signed-off-by: Matthieu Buffet <matthieu@buffet.re> --- samples/landlock/sandboxer.c | 86 ++++++++++++++++++++---------------- 1 file changed, 48 insertions(+), 38 deletions(-)