summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDavid Decotigny2018-05-24 08:30:15 -0700
committerDenys Vlasenko2018-05-24 18:34:56 +0200
commit8f48fc01e9e43d16bf5860fa37252b43c76cb395 (patch)
tree8762e416ece3a9f6c80c5760f5054de9b491c5e2
parenta174c791ece5d7f2869e9efd338d91c8ea10f609 (diff)
downloadbusybox-8f48fc01e9e43d16bf5860fa37252b43c76cb395.zip
busybox-8f48fc01e9e43d16bf5860fa37252b43c76cb395.tar.gz
udhcpc6: carry along length of packet when parsing it.
This is to avoid parsing garbage past packet's actual end. Also const-ize params to a few functions. function old new delta d6_run_script_no_option - 12 +12 option_to_env 791 798 +7 d6_run_script 253 255 +2 perform_d6_release 95 93 -2 udhcpc6_main 2596 2592 -4 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 2/2 up/down: 21/-6) Total: 15 bytes Signed-off-by: David Decotigny <ddecotig@gmail.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r--networking/udhcp/d6_dhcpc.c39
1 files changed, 24 insertions, 15 deletions
diff --git a/networking/udhcp/d6_dhcpc.c b/networking/udhcp/d6_dhcpc.c
index 2ff9c56..4dbc2b1 100644
--- a/networking/udhcp/d6_dhcpc.c
+++ b/networking/udhcp/d6_dhcpc.c
@@ -215,7 +215,8 @@ static char** new_env(void)
return &client6_data.env_ptr[client6_data.env_idx++];
}
-static char *string_option_to_env(uint8_t *option, uint8_t *option_end)
+static char *string_option_to_env(const uint8_t *option,
+ const uint8_t *option_end)
{
const char *ptr, *name = NULL;
unsigned val_len;
@@ -244,7 +245,7 @@ static char *string_option_to_env(uint8_t *option, uint8_t *option_end)
}
/* put all the parameters into the environment */
-static void option_to_env(uint8_t *option, uint8_t *option_end)
+static void option_to_env(const uint8_t *option, const uint8_t *option_end)
{
#if ENABLE_FEATURE_UDHCPC6_RFC3646
int addrs, option_offset;
@@ -422,7 +423,7 @@ static void option_to_env(uint8_t *option, uint8_t *option_end)
}
}
-static char **fill_envp(struct d6_packet *packet)
+static char **fill_envp(const uint8_t *option, const uint8_t *option_end)
{
char **envp, **curr;
@@ -431,8 +432,8 @@ static char **fill_envp(struct d6_packet *packet)
*new_env() = xasprintf("interface=%s", client_config.interface);
- if (packet)
- option_to_env(packet->d6_options, packet->d6_options + sizeof(packet->d6_options));
+ if (option)
+ option_to_env(option, option_end);
envp = curr = client6_data.env_ptr;
while (*curr)
@@ -442,12 +443,13 @@ static char **fill_envp(struct d6_packet *packet)
}
/* Call a script with a par file and env vars */
-static void d6_run_script(struct d6_packet *packet, const char *name)
+static void d6_run_script(const uint8_t *option, const uint8_t *option_end,
+ const char *name)
{
char **envp, **curr;
char *argv[3];
- envp = fill_envp(packet);
+ envp = fill_envp(option, option_end);
/* call script */
log1("executing %s %s", client_config.script, name);
@@ -463,6 +465,11 @@ static void d6_run_script(struct d6_packet *packet, const char *name)
free(envp);
}
+/* Call a script with a par file and no env var */
+static void d6_run_script_no_option(const char *name)
+{
+ d6_run_script(NULL, NULL, name);
+}
/*** Sending/receiving packets ***/
@@ -1038,7 +1045,7 @@ static void perform_renew(void)
state = RENEW_REQUESTED;
break;
case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
- d6_run_script(NULL, "deconfig");
+ d6_run_script_no_option("deconfig");
case REQUESTING:
case RELEASED:
change_listen_mode(LISTEN_RAW);
@@ -1067,7 +1074,7 @@ static void perform_d6_release(struct in6_addr *server_ipv6, struct in6_addr *ou
* Users requested to be notified in all cases, even if not in one
* of the states above.
*/
- d6_run_script(NULL, "deconfig");
+ d6_run_script_no_option("deconfig");
change_listen_mode(LISTEN_NONE);
state = RELEASED;
}
@@ -1276,7 +1283,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
udhcp_sp_setup();
state = INIT_SELECTING;
- d6_run_script(NULL, "deconfig");
+ d6_run_script_no_option("deconfig");
change_listen_mode(LISTEN_RAW);
packet_num = 0;
timeout = 0;
@@ -1357,7 +1364,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
continue;
}
leasefail:
- d6_run_script(NULL, "leasefail");
+ d6_run_script_no_option("leasefail");
#if BB_MMU /* -b is not supported on NOMMU */
if (opt & OPT_b) { /* background if no lease */
bb_error_msg("no lease, forking to background");
@@ -1431,7 +1438,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
}
/* Timed out, enter init state */
bb_error_msg("lease lost, entering init state");
- d6_run_script(NULL, "deconfig");
+ d6_run_script_no_option("deconfig");
state = INIT_SELECTING;
client_config.first_secs = 0; /* make secs field count from 0 */
/*timeout = 0; - already is */
@@ -1538,9 +1545,10 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
if (option && (option->data[0] | option->data[1]) != 0) {
/* return to init state */
bb_error_msg("received DHCP NAK (%u)", option->data[4]);
- d6_run_script(&packet, "nak");
+ d6_run_script(packet.d6_options,
+ packet_end, "nak");
if (state != REQUESTING)
- d6_run_script(NULL, "deconfig");
+ d6_run_script_no_option("deconfig");
change_listen_mode(LISTEN_RAW);
sleep(3); /* avoid excessive network traffic */
state = INIT_SELECTING;
@@ -1737,7 +1745,8 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
if (timeout < 0x10)
timeout = 0x10;
/* enter bound state */
- d6_run_script(&packet, state == REQUESTING ? "bound" : "renew");
+ d6_run_script(packet.d6_options, packet_end,
+ (state == REQUESTING ? "bound" : "renew"));
state = BOUND;
change_listen_mode(LISTEN_NONE);