diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/kobject_uevent.c | 167 |
1 files changed, 154 insertions, 13 deletions
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index 9a2b811966eb..719c155fce20 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -23,6 +23,8 @@ #include <linux/socket.h> #include <linux/skbuff.h> #include <linux/netlink.h> +#include <linux/uuid.h> +#include <linux/ctype.h> #include <net/sock.h> #include <net/net_namespace.h> @@ -52,19 +54,13 @@ static const char *kobject_actions[] = { [KOBJ_OFFLINE] = "offline", }; -/** - * kobject_action_type - translate action string to numeric type - * - * @buf: buffer containing the action string, newline is ignored - * @count: length of buffer - * @type: pointer to the location to store the action type - * - * Returns 0 if the action string was recognized. - */ -int kobject_action_type(const char *buf, size_t count, - enum kobject_action *type) +static int kobject_action_type(const char *buf, size_t count, + enum kobject_action *type, + const char **args) { enum kobject_action action; + size_t count_first; + const char *args_start; int ret = -EINVAL; if (count && (buf[count-1] == '\n' || buf[count-1] == '\0')) @@ -73,11 +69,20 @@ int kobject_action_type(const char *buf, size_t count, if (!count) goto out; + args_start = strnchr(buf, count, ' '); + if (args_start) { + count_first = args_start - buf; + args_start = args_start + 1; + } else + count_first = count; + for (action = 0; action < ARRAY_SIZE(kobject_actions); action++) { - if (strncmp(kobject_actions[action], buf, count) != 0) + if (strncmp(kobject_actions[action], buf, count_first) != 0) continue; - if (kobject_actions[action][count] != '\0') + if (kobject_actions[action][count_first] != '\0') continue; + if (args) + *args = args_start; *type = action; ret = 0; break; @@ -86,6 +91,142 @@ out: return ret; } +static const char *action_arg_word_end(const char *buf, const char *buf_end, + char delim) +{ + const char *next = buf; + + while (next <= buf_end && *next != delim) + if (!isalnum(*next++)) + return NULL; + + if (next == buf) + return NULL; + + return next; +} + +static int kobject_action_args(const char *buf, size_t count, + struct kobj_uevent_env **ret_env) +{ + struct kobj_uevent_env *env = NULL; + const char *next, *buf_end, *key; + int key_len; + int r = -EINVAL; + + if (count && (buf[count - 1] == '\n' || buf[count - 1] == '\0')) + count--; + + if (!count) + return -EINVAL; + + env = kzalloc(sizeof(*env), GFP_KERNEL); + if (!env) + return -ENOMEM; + + /* first arg is UUID */ + if (count < UUID_STRING_LEN || !uuid_is_valid(buf) || + add_uevent_var(env, "SYNTH_UUID=%.*s", UUID_STRING_LEN, buf)) + goto out; + + /* + * the rest are custom environment variables in KEY=VALUE + * format with ' ' delimiter between each KEY=VALUE pair + */ + next = buf + UUID_STRING_LEN; + buf_end = buf + count - 1; + + while (next <= buf_end) { + if (*next != ' ') + goto out; + + /* skip the ' ', key must follow */ + key = ++next; + if (key > buf_end) + goto out; + + buf = next; + next = action_arg_word_end(buf, buf_end, '='); + if (!next || next > buf_end || *next != '=') + goto out; + key_len = next - buf; + + /* skip the '=', value must follow */ + if (++next > buf_end) + goto out; + + buf = next; + next = action_arg_word_end(buf, buf_end, ' '); + if (!next) + goto out; + + if (add_uevent_var(env, "SYNTH_ARG_%.*s=%.*s", + key_len, key, (int) (next - buf), buf)) + goto out; + } + + r = 0; +out: + if (r) + kfree(env); + else + *ret_env = env; + return r; +} + +/** + * kobject_synth_uevent - send synthetic uevent with arguments + * + * @kobj: struct kobject for which synthetic uevent is to be generated + * @buf: buffer containing action type and action args, newline is ignored + * @count: length of buffer + * + * Returns 0 if kobject_synthetic_uevent() is completed with success or the + * corresponding error when it fails. + */ +int kobject_synth_uevent(struct kobject *kobj, const char *buf, size_t count) +{ + char *no_uuid_envp[] = { "SYNTH_UUID=0", NULL }; + enum kobject_action action; + const char *action_args; + struct kobj_uevent_env *env; + const char *msg = NULL, *devpath; + int r; + + r = kobject_action_type(buf, count, &action, &action_args); + if (r) { + msg = "unknown uevent action string\n"; + goto out; + } + + if (!action_args) { + r = kobject_uevent_env(kobj, action, no_uuid_envp); + goto out; + } + + r = kobject_action_args(action_args, + count - (action_args - buf), &env); + if (r == -EINVAL) { + msg = "incorrect uevent action arguments\n"; + goto out; + } + + if (r) + goto out; + + r = kobject_uevent_env(kobj, action, env->envp); + kfree(env); +out: + if (r) { + devpath = kobject_get_path(kobj, GFP_KERNEL); + printk(KERN_WARNING "synth uevent: %s: %s", + devpath ?: "unknown device", + msg ?: "failed to send uevent"); + kfree(devpath); + } + return r; +} + #ifdef CONFIG_NET static int kobj_bcast_filter(struct sock *dsk, struct sk_buff *skb, void *data) { |