lib: Rewrite ipv6 prefix matcher

Simplify ipv6 prefix matcher / validator to use standard Linux
networking functions instead of a state machine.

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>
Reviewed-by: Donald Sharp <sharpd@cumulusnetworks.com>
Reviewed-by: Don Slice <dslice@cumulusnetworks.com>
This commit is contained in:
Quentin Young 2016-06-27 13:14:18 +00:00
parent 2caa9b3957
commit 4c58c70dcb

View File

@ -1001,15 +1001,8 @@ cmd_ipv4_prefix_match (const char *str)
return exact_match;
}
#define IPV6_ADDR_STR "0123456789abcdefABCDEF:.%"
#define IPV6_PREFIX_STR "0123456789abcdefABCDEF:.%/"
#define STATE_START 1
#define STATE_COLON 2
#define STATE_DOUBLE 3
#define STATE_ADDR 4
#define STATE_DOT 5
#define STATE_SLASH 6
#define STATE_MASK 7
#define IPV6_ADDR_STR "0123456789abcdefABCDEF:.%"
#define IPV6_PREFIX_STR "0123456789abcdefABCDEF:.%/"
#ifdef HAVE_IPV6
@ -1040,11 +1033,10 @@ cmd_ipv6_match (const char *str)
static enum match_type
cmd_ipv6_prefix_match (const char *str)
{
int state = STATE_START;
int colons = 0, nums = 0, double_colon = 0;
int mask;
const char *sp = NULL;
char *endptr = NULL;
struct sockaddr_in6 sin6_dummy;
const char *delim = "/\0";
char *dupe, *prefix, *mask, *context, *endptr;
int nmask = -1;
if (str == NULL)
return partly_match;
@ -1052,116 +1044,26 @@ cmd_ipv6_prefix_match (const char *str)
if (strspn (str, IPV6_PREFIX_STR) != strlen (str))
return no_match;
while (*str != '\0' && state != STATE_MASK)
{
switch (state)
{
case STATE_START:
if (*str == ':')
{
if (*(str + 1) != ':' && *(str + 1) != '\0')
return no_match;
colons--;
state = STATE_COLON;
}
else
{
sp = str;
state = STATE_ADDR;
}
/* tokenize to address + mask */
dupe = XMALLOC(MTYPE_TMP, strlen(str)+1);
strncpy(dupe, str, strlen(str)+1);
prefix = strtok_r(dupe, delim, &context);
mask = strtok_r(NULL, delim, &context);
continue;
case STATE_COLON:
colons++;
if (*(str + 1) == '/')
return no_match;
else if (*(str + 1) == ':')
state = STATE_DOUBLE;
else
{
sp = str + 1;
state = STATE_ADDR;
}
break;
case STATE_DOUBLE:
if (double_colon)
return no_match;
if (*(str + 1) == ':')
return no_match;
else
{
if (*(str + 1) != '\0' && *(str + 1) != '/')
colons++;
sp = str + 1;
if (*(str + 1) == '/')
state = STATE_SLASH;
else
state = STATE_ADDR;
}
double_colon++;
nums += 1;
break;
case STATE_ADDR:
if (*(str + 1) == ':' || *(str + 1) == '.'
|| *(str + 1) == '\0' || *(str + 1) == '/')
{
if (str - sp > 3)
return no_match;
for (; sp <= str; sp++)
if (*sp == '/')
return no_match;
nums++;
if (*(str + 1) == ':')
state = STATE_COLON;
else if (*(str + 1) == '.')
{
if (colons || double_colon)
state = STATE_DOT;
else
return no_match;
}
else if (*(str + 1) == '/')
state = STATE_SLASH;
}
break;
case STATE_DOT:
state = STATE_ADDR;
break;
case STATE_SLASH:
if (*(str + 1) == '\0')
return partly_match;
state = STATE_MASK;
break;
default:
break;
}
if (nums > 11)
return no_match;
if (colons > 7)
return no_match;
str++;
}
if (state < STATE_MASK)
if (!mask)
return partly_match;
mask = strtol (str, &endptr, 10);
if (*endptr != '\0')
/* validate prefix */
if (inet_pton(AF_INET6, prefix, &sin6_dummy.sin6_addr) != 1)
return no_match;
if (mask < 0 || mask > 128)
/* validate mask */
nmask = strtol (mask, &endptr, 10);
if (*endptr != '\0' || nmask < 0 || nmask > 128)
return no_match;
XFREE(MTYPE_TMP, dupe);
return exact_match;
}