diff options
| -rw-r--r-- | sbin/dhclient/dhclient.c | 42 | ||||
| -rw-r--r-- | sbin/dhclient/options.c | 4 |
2 files changed, 24 insertions, 22 deletions
diff --git a/sbin/dhclient/dhclient.c b/sbin/dhclient/dhclient.c index 2a43082..b68f636 100644 --- a/sbin/dhclient/dhclient.c +++ b/sbin/dhclient/dhclient.c @@ -107,7 +107,11 @@ struct pidfh *pidfile; */ #define ASSERT_STATE(state_is, state_shouldbe) {} -#define TIME_MAX 2147483647 +/* + * We need to check that the expiry, renewal and rebind times are not beyond + * the end of time (~2038 when a 32-bit time_t is being used). + */ +#define TIME_MAX ((((time_t) 1 << (sizeof(time_t) * CHAR_BIT - 2)) - 1) * 2 + 1) int log_priority; int no_daemon; @@ -762,15 +766,17 @@ dhcpack(struct packet *packet) else ip->client->new->expiry = default_lease_time; /* A number that looks negative here is really just very large, - because the lease expiry offset is unsigned. */ - if (ip->client->new->expiry < 0) - ip->client->new->expiry = TIME_MAX; + because the lease expiry offset is unsigned. Also make sure that + the addition of cur_time below does not overflow (a 32 bit) time_t. */ + if (ip->client->new->expiry < 0 || + ip->client->new->expiry > TIME_MAX - cur_time) + ip->client->new->expiry = TIME_MAX - cur_time; /* XXX should be fixed by resetting the client state */ if (ip->client->new->expiry < 60) ip->client->new->expiry = 60; /* Unless overridden in the config, take the server-provided renewal - * time if there is one; otherwise figure it out according to the spec. + * time if there is one. Otherwise figure it out according to the spec. * Also make sure the renewal time does not exceed the expiry time. */ if (ip->client->config->default_actions[DHO_DHCP_RENEWAL_TIME] == @@ -782,7 +788,8 @@ dhcpack(struct packet *packet) ip->client->new->options[DHO_DHCP_RENEWAL_TIME].data); else ip->client->new->renewal = ip->client->new->expiry / 2; - if (ip->client->new->renewal > ip->client->new->expiry / 2) + if (ip->client->new->renewal < 0 || + ip->client->new->renewal > ip->client->new->expiry / 2) ip->client->new->renewal = ip->client->new->expiry / 2; /* Same deal with the rebind time. */ @@ -794,20 +801,15 @@ dhcpack(struct packet *packet) ip->client->new->rebind = getULong( ip->client->new->options[DHO_DHCP_REBINDING_TIME].data); else - ip->client->new->rebind = ip->client->new->renewal * 7 / 4; - if (ip->client->new->rebind > ip->client->new->renewal * 7 / 4) - ip->client->new->rebind = ip->client->new->renewal * 7 / 4; - - ip->client->new->expiry += cur_time; - /* Lease lengths can never be negative. */ - if (ip->client->new->expiry < cur_time) - ip->client->new->expiry = TIME_MAX; - ip->client->new->renewal += cur_time; - if (ip->client->new->renewal < cur_time) - ip->client->new->renewal = TIME_MAX; - ip->client->new->rebind += cur_time; - if (ip->client->new->rebind < cur_time) - ip->client->new->rebind = TIME_MAX; + ip->client->new->rebind = ip->client->new->renewal / 4 * 7; + if (ip->client->new->rebind < 0 || + ip->client->new->rebind > ip->client->new->renewal / 4 * 7) + ip->client->new->rebind = ip->client->new->renewal / 4 * 7; + + /* Convert the time offsets into seconds-since-the-epoch */ + ip->client->new->expiry += cur_time; + ip->client->new->renewal += cur_time; + ip->client->new->rebind += cur_time; bind_lease(ip); } diff --git a/sbin/dhclient/options.c b/sbin/dhclient/options.c index be073da..fe025e6 100644 --- a/sbin/dhclient/options.c +++ b/sbin/dhclient/options.c @@ -783,7 +783,7 @@ pretty_print_option(unsigned int code, unsigned char *data, int len, dp += 4; break; case 'L': - opcount = snprintf(op, opleft, "%ld", + opcount = snprintf(op, opleft, "%lu", (unsigned long)getULong(dp)); if (opcount >= opleft || opcount == -1) goto toobig; @@ -799,7 +799,7 @@ pretty_print_option(unsigned int code, unsigned char *data, int len, dp += 2; break; case 'S': - opcount = snprintf(op, opleft, "%d", + opcount = snprintf(op, opleft, "%u", getUShort(dp)); if (opcount >= opleft || opcount == -1) goto toobig; |
