blob: 4aba95c863ea10fb85e3e643208fba548337083b [file] [log] [blame]
/*
* plugin.c: plugin handling
*
* Copyright (c) 2011 Cisco and/or its affiliates.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <vlib/unix/plugin.h>
#include <vppinfra/elf.h>
#include <dlfcn.h>
#include <dirent.h>
plugin_main_t vlib_plugin_main;
char *vlib_plugin_path __attribute__ ((weak));
char *vlib_plugin_path = "";
char *vlib_plugin_app_version __attribute__ ((weak));
char *vlib_plugin_app_version = "";
void *
vlib_get_plugin_symbol (char *plugin_name, char *symbol_name)
{
plugin_main_t *pm = &vlib_plugin_main;
uword *p;
plugin_info_t *pi;
if ((p = hash_get_mem (pm->plugin_by_name_hash, plugin_name)) == 0)
return 0;
pi = vec_elt_at_index (pm->plugin_info, p[0]);
return dlsym (pi->handle, symbol_name);
}
static char *
str_array_to_vec (char *array, int len)
{
char c, *r = 0;
int n = 0;
do
{
c = array[n];
vec_add1 (r, c);
}
while (c && ++n < len);
if (c)
vec_add1 (r, 0);
return r;
}
static int
load_one_plugin (plugin_main_t * pm, plugin_info_t * pi, int from_early_init)
{
void *handle;
clib_error_t *error;
elf_main_t em = { 0 };
elf_section_t *section;
u8 *data;
char *version_required;
vlib_plugin_registration_t *reg;
plugin_config_t *pc = 0;
uword *p;
if (elf_read_file (&em, (char *) pi->filename))
return -1;
error = elf_get_section_by_name (&em, ".vlib_plugin_registration",
&section);
if (error)
{
clib_warning ("Not a plugin: %s\n", (char *) pi->name);
return -1;
}
data = elf_get_section_contents (&em, section->index, 1);
reg = (vlib_plugin_registration_t *) data;
if (vec_len (data) != sizeof (*reg))
{
clib_warning ("vlib_plugin_registration size mismatch in plugin %s\n",
(char *) pi->name);
goto error;
}
p = hash_get_mem (pm->config_index_by_name, pi->name);
if (p)
{
pc = vec_elt_at_index (pm->configs, p[0]);
if (pc->is_disabled)
{
clib_warning ("Plugin disabled: %s", pi->name);
goto error;
}
if (reg->default_disabled && pc->is_enabled == 0)
{
clib_warning ("Plugin disabled: %s (default)", pi->name);
goto error;
}
}
else if (reg->default_disabled)
{
clib_warning ("Plugin disabled: %s (default)", pi->name);
goto error;
}
version_required = str_array_to_vec ((char *) &reg->version_required,
sizeof (reg->version_required));
if ((strlen (version_required) > 0) &&
(strncmp (vlib_plugin_app_version, version_required,
strlen (version_required))))
{
clib_warning ("Plugin %s version mismatch: %s != %s",
pi->name, vlib_plugin_app_version, reg->version_required);
if (!(pc && pc->skip_version_check == 1))
{
vec_free (version_required);
goto error;
}
}
vec_free (version_required);
vec_free (data);
elf_main_free (&em);
handle = dlopen ((char *) pi->filename, RTLD_LAZY);
/*
* Note: this can happen if the plugin has an undefined symbol reference,
* so print a warning. Otherwise, the poor slob won't know what happened.
* Ask me how I know that...
*/
if (handle == 0)
{
clib_warning ("%s", dlerror ());
return -1;
}
pi->handle = handle;
reg = dlsym (pi->handle, "vlib_plugin_registration");
if (reg == 0)
{
/* This should never happen unless somebody chagnes registration macro */
clib_warning ("Missing plugin registration in plugin '%s'", pi->name);
os_exit (1);
}
pi->reg = reg;
pi->version = str_array_to_vec ((char *) &reg->version,
sizeof (reg->version));
if (reg && reg->early_init)
{
clib_error_t *(*ei) (vlib_main_t *);
void *h;
h = dlsym (pi->handle, reg->early_init);
if (h)
{
ei = h;
error = (*ei) (pm->vlib_main);
if (error)
{
clib_error_report (error);
os_exit (1);
}
}
else
clib_warning ("Plugin %s: early init function %s set but not found",
(char *) pi->name, reg->early_init);
}
clib_warning ("Loaded plugin: %s", pi->name);
return 0;
error:
vec_free (data);
elf_main_free (&em);
return -1;
}
static u8 **
split_plugin_path (plugin_main_t * pm)
{
int i;
u8 **rv = 0;
u8 *path = pm->plugin_path;
u8 *this = 0;
for (i = 0; i < vec_len (pm->plugin_path); i++)
{
if (path[i] != ':')
{
vec_add1 (this, path[i]);
continue;
}
vec_add1 (this, 0);
vec_add1 (rv, this);
this = 0;
}
if (this)
{
vec_add1 (this, 0);
vec_add1 (rv, this);
}
return rv;
}
int
vlib_load_new_plugins (plugin_main_t * pm, int from_early_init)
{
DIR *dp;
struct dirent *entry;
struct stat statb;
uword *p;
plugin_info_t *pi;
u8 **plugin_path;
int i;
plugin_path = split_plugin_path (pm);
for (i = 0; i < vec_len (plugin_path); i++)
{
dp = opendir ((char *) plugin_path[i]);
if (dp == 0)
continue;
while ((entry = readdir (dp)))
{
u8 *plugin_name;
u8 *filename;
if (pm->plugin_name_filter)
{
int j;
for (j = 0; j < vec_len (pm->plugin_name_filter); j++)
if (entry->d_name[j] != pm->plugin_name_filter[j])
goto next;
}
filename = format (0, "%s/%s%c", plugin_path[i], entry->d_name, 0);
/* Only accept .so */
char *ext = strrchr ((const char *) filename, '.');
/* unreadable */
if (!ext || (strcmp (ext, ".so") != 0) ||
stat ((char *) filename, &statb) < 0)
{
ignore:
vec_free (filename);
continue;
}
/* a dir or other things which aren't plugins */
if (!S_ISREG (statb.st_mode))
goto ignore;
plugin_name = format (0, "%s%c", entry->d_name, 0);
p = hash_get_mem (pm->plugin_by_name_hash, plugin_name);
if (p == 0)
{
vec_add2 (pm->plugin_info, pi, 1);
pi->name = plugin_name;
pi->filename = filename;
pi->file_info = statb;
if (load_one_plugin (pm, pi, from_early_init))
{
vec_free (plugin_name);
vec_free (filename);
_vec_len (pm->plugin_info) = vec_len (pm->plugin_info) - 1;
memset (pi, 0, sizeof (*pi));
continue;
}
hash_set_mem (pm->plugin_by_name_hash, plugin_name,
pi - pm->plugin_info);
}
next:
;
}
closedir (dp);
vec_free (plugin_path[i]);
}
vec_free (plugin_path);
return 0;
}
int
vlib_plugin_early_init (vlib_main_t * vm)
{
plugin_main_t *pm = &vlib_plugin_main;
if (pm->plugin_path == 0)
pm->plugin_path = format (0, "%s%c", vlib_plugin_path, 0);
clib_warning ("plugin path %s", pm->plugin_path);
pm->plugin_by_name_hash = hash_create_string (0, sizeof (uword));
pm->vlib_main = vm;
return vlib_load_new_plugins (pm, 1 /* from_early_init */ );
}
static clib_error_t *
vlib_plugins_show_cmd_fn (vlib_main_t * vm,
unformat_input_t * input, vlib_cli_command_t * cmd)
{
plugin_main_t *pm = &vlib_plugin_main;
u8 *s = 0;
u8 *key = 0;
uword value = 0;
int index = 1;
plugin_info_t *pi;
s = format (s, " Plugin path is: %s\n\n", pm->plugin_path);
s = format (s, " %-41s%s\n", "Plugin", "Version");
/* *INDENT-OFF* */
hash_foreach_mem (key, value, pm->plugin_by_name_hash,
{
if (key != 0)
{
pi = vec_elt_at_index (pm->plugin_info, value);
s = format (s, "%3d. %-40s %s\n", index, key, pi->version);
index++;
}
});
/* *INDENT-ON* */
vlib_cli_output (vm, "%v", s);
vec_free (s);
return 0;
}
/* *INDENT-OFF* */
VLIB_CLI_COMMAND (plugins_show_cmd, static) =
{
.path = "show plugins",
.short_help = "show loaded plugins",
.function = vlib_plugins_show_cmd_fn,
};
/* *INDENT-ON* */
static clib_error_t *
config_one_plugin (vlib_main_t * vm, char *name, unformat_input_t * input)
{
plugin_main_t *pm = &vlib_plugin_main;
plugin_config_t *pc;
clib_error_t *error = 0;
uword *p;
int is_enable = 0;
int is_disable = 0;
int skip_version_check = 0;
if (pm->config_index_by_name == 0)
pm->config_index_by_name = hash_create_string (0, sizeof (uword));
p = hash_get_mem (pm->config_index_by_name, name);
if (p)
{
error = clib_error_return (0, "plugin '%s' already configured", name);
goto done;
}
while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
{
if (unformat (input, "enable"))
is_enable = 1;
else if (unformat (input, "disable"))
is_disable = 1;
else if (unformat (input, "skip-version-check"))
skip_version_check = 1;
else
{
error = clib_error_return (0, "unknown input '%U'",
format_unformat_error, input);
goto done;
}
}
if (is_enable && is_disable)
{
error = clib_error_return (0, "please specify either enable or disable"
" for plugin '%s'", name);
goto done;
}
vec_add2 (pm->configs, pc, 1);
hash_set_mem (pm->config_index_by_name, name, pc - pm->configs);
pc->is_enabled = is_enable;
pc->is_disabled = is_disable;
pc->skip_version_check = skip_version_check;
pc->name = name;
done:
return error;
}
clib_error_t *
vlib_plugin_config (vlib_main_t * vm, unformat_input_t * input)
{
plugin_main_t *pm = &vlib_plugin_main;
clib_error_t *error = 0;
unformat_input_t in;
unformat_init (&in, 0, 0);
while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
{
u8 *s, *v;
if (unformat (input, "%s %v", &s, &v))
{
if (strncmp ((const char *) s, "plugins", 8) == 0)
{
if (vec_len (in.buffer) > 0)
vec_add1 (in.buffer, ' ');
vec_add (in.buffer, v, vec_len (v));
}
}
else
{
error = clib_error_return (0, "unknown input '%U'",
format_unformat_error, input);
goto done;
}
vec_free (v);
vec_free (s);
}
done:
input = &in;
while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
{
unformat_input_t sub_input;
u8 *s = 0;
if (unformat (input, "path %s", &s))
pm->plugin_path = s;
else if (unformat (input, "plugin %s %U", &s,
unformat_vlib_cli_sub_input, &sub_input))
{
error = config_one_plugin (vm, (char *) s, &sub_input);
unformat_free (&sub_input);
if (error)
goto done2;
}
else
{
error = clib_error_return (0, "unknown input '%U'",
format_unformat_error, input);
{
vec_free (s);
goto done2;
}
}
}
done2:
unformat_free (&in);
return error;
}
/* discard whole 'plugins' section, as it is already consumed prior to
plugin load */
static clib_error_t *
plugins_config (vlib_main_t * vm, unformat_input_t * input)
{
u8 *junk;
while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
{
if (unformat (input, "%s", &junk))
{
vec_free (junk);
return 0;
}
else
return clib_error_return (0, "unknown input '%U'",
format_unformat_error, input);
}
return 0;
}
VLIB_CONFIG_FUNCTION (plugins_config, "plugins");
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/