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dhcpd: remember and record hostnames; optimize get_option

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dumpleases: show hostnames

function                                             old     new   delta
add_lease                                            230     292     +62
send_offer                                           403     421     +18
send_ACK                                             232     249     +17
read_leases                                          249     258      +9
dumpleases_main                                      604     609      +5
nobody_responds_to_arp                                84      86      +2
udhcp_end_option                                      32      30      -2
udhcp_get_option                                     222     171     -51
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 6/2 up/down: 113/-53)            Total: 60 bytes
This commit is contained in:
Denis Vlasenko
2009-04-01 12:36:09 +00:00
parent 3266aa9ec2
commit bd79c3d337
8 changed files with 145 additions and 120 deletions
Download Patch File Download Diff File Expand all files Collapse all files

94
networking/udhcp/options.c
View File

@@ -119,58 +119,61 @@ const uint8_t dhcp_option_lengths[] ALIGN1 = {
};
/* get an option with bounds checking (warning, not aligned). */
/* get an option with bounds checking (warning, result is not aligned). */
uint8_t* FAST_FUNC get_option(struct dhcpMessage *packet, int code)
{
int i, length;
uint8_t *optionptr;
int over = 0;
int curr = OPTION_FIELD;
int len;
int rem;
int overload = 0;
enum {
FILE_FIELD101 = FILE_FIELD * 0x101,
SNAME_FIELD101 = SNAME_FIELD * 0x101,
};
/* option bytes: [code][len][data1][data2]..[dataLEN] */
optionptr = packet->options;
i = 0;
length = sizeof(packet->options);
rem = sizeof(packet->options);
while (1) {
if (i >= length) {
bb_error_msg("bogus packet, option fields too long");
if (rem <= 0) {
bb_error_msg("bogus packet, malformed option field");
return NULL;
}
if (optionptr[i + OPT_CODE] == code) {
if (i + 1 + optionptr[i + OPT_LEN] >= length) {
bb_error_msg("bogus packet, option fields too long");
return NULL;
}
return optionptr + i + 2;
if (optionptr[OPT_CODE] == DHCP_PADDING) {
rem--;
optionptr++;
continue;
}
switch (optionptr[i + OPT_CODE]) {
case DHCP_PADDING:
i++;
break;
case DHCP_OPTION_OVER:
if (i + 1 + optionptr[i + OPT_LEN] >= length) {
bb_error_msg("bogus packet, option fields too long");
return NULL;
}
over = optionptr[i + 3];
i += optionptr[OPT_LEN] + 2;
break;
case DHCP_END:
if (curr == OPTION_FIELD && (over & FILE_FIELD)) {
if (optionptr[OPT_CODE] == DHCP_END) {
if ((overload & FILE_FIELD101) == FILE_FIELD) {
/* can use packet->file, and didn't look at it yet */
overload |= FILE_FIELD101; /* "we looked at it" */
optionptr = packet->file;
i = 0;
length = sizeof(packet->file);
curr = FILE_FIELD;
} else if (curr == FILE_FIELD && (over & SNAME_FIELD)) {
rem = sizeof(packet->file);
continue;
}
if ((overload & SNAME_FIELD101) == SNAME_FIELD) {
/* can use packet->sname, and didn't look at it yet */
overload |= SNAME_FIELD101; /* "we looked at it" */
optionptr = packet->sname;
i = 0;
length = sizeof(packet->sname);
curr = SNAME_FIELD;
} else
return NULL;
break;
default:
i += optionptr[OPT_LEN + i] + 2;
rem = sizeof(packet->sname);
continue;
}
return NULL;
}
len = 2 + optionptr[OPT_LEN];
rem -= len;
if (rem < 0)
continue; /* complain and return NULL */
if (optionptr[OPT_CODE] == code)
return optionptr + OPT_DATA;
if (optionptr[OPT_CODE] == DHCP_OPTION_OVERLOAD) {
overload |= optionptr[OPT_DATA];
/* fall through */
}
optionptr += len;
}
return NULL;
}
@@ -182,17 +185,16 @@ int FAST_FUNC end_option(uint8_t *optionptr)
int i = 0;
while (optionptr[i] != DHCP_END) {
if (optionptr[i] == DHCP_PADDING)
i++;
else
i += optionptr[i + OPT_LEN] + 2;
if (optionptr[i] != DHCP_PADDING)
i += optionptr[i + OPT_LEN] + 1;
i++;
}
return i;
}
/* add an option string to the options (an option string contains an option code,
* length, then data) */
/* add an option string to the options */
/* option bytes: [code][len][data1][data2]..[dataLEN] */
int FAST_FUNC add_option_string(uint8_t *optionptr, uint8_t *string)
{
int end = end_option(optionptr);