/*
* Argument parser
* Copyright © Jan Engelhardt, 2011
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*/
#include <ctype.h>
#include <errno.h>
#include <getopt.h>
#include <limits.h>
#include <netdb.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <arpa/inet.h>
#include <netinet/ip.h>
#include "xtables.h"
#include "xshared.h"
#ifndef IPTOS_NORMALSVC
# define IPTOS_NORMALSVC 0
#endif
#define XTOPT_MKPTR(cb) \
((void *)((char *)(cb)->data + (cb)->entry->ptroff))
/**
* Simple key-value pairs for syslog levels
*/
struct syslog_level {
char name[8];
uint8_t level;
};
struct tos_value_mask {
uint8_t value, mask;
};
static const size_t xtopt_psize[] = {
/*
* All types not listed here, and thus essentially being initialized to
* zero have zero on purpose.
*/
[XTTYPE_UINT8] = sizeof(uint8_t),
[XTTYPE_UINT16] = sizeof(uint16_t),
[XTTYPE_UINT32] = sizeof(uint32_t),
[XTTYPE_UINT64] = sizeof(uint64_t),
[XTTYPE_UINT8RC] = sizeof(uint8_t[2]),
[XTTYPE_UINT16RC] = sizeof(uint16_t[2]),
[XTTYPE_UINT32RC] = sizeof(uint32_t[2]),
[XTTYPE_UINT64RC] = sizeof(uint64_t[2]),
[XTTYPE_DOUBLE] = sizeof(double),
[XTTYPE_STRING] = -1,
[XTTYPE_SYSLOGLEVEL] = sizeof(uint8_t),
[XTTYPE_HOST] = sizeof(union nf_inet_addr),
[XTTYPE_HOSTMASK] = sizeof(union nf_inet_addr),
[XTTYPE_PROTOCOL] = sizeof(uint8_t),
[XTTYPE_PORT] = sizeof(uint16_t),
[XTTYPE_PORTRC] = sizeof(uint16_t[2]),
[XTTYPE_PLENMASK] = sizeof(union nf_inet_addr),
[XTTYPE_ETHERMAC] = sizeof(uint8_t[6]),
};
/**
* Creates getopt options from the x6-style option map, and assigns each a
* getopt id.
*/
struct option *
xtables_options_xfrm(struct option *orig_opts, struct option *oldopts,
const struct xt_option_entry *entry, unsigned int *offset)
{
unsigned int num_orig, num_old = 0, num_new, i;
struct option *merge, *mp;
if (entry == NULL)
return oldopts;
for (num_orig = 0; orig_opts[num_orig].name != NULL; ++num_orig)
;
if (oldopts != NULL)
for (num_old = 0; oldopts[num_old].name != NULL; ++num_old)
;
for (num_new = 0; entry[num_new].name != NULL; ++num_new)
;
/*
* Since @oldopts also has @orig_opts already (and does so at the
* start), skip these entries.
*/
oldopts += num_orig;
num_old -= num_orig;
merge = malloc(sizeof(*mp) * (num_orig + num_old + num_new + 1));
if (merge == NULL)
return NULL;
/* Let the base options -[ADI...] have precedence over everything */
memcpy(merge, orig_opts, sizeof(*mp) * num_orig);
mp = merge + num_orig;
/* Second, the new options */
xt_params->option_offset += XT_OPTION_OFFSET_SCALE;
*offset = xt_params->option_offset;
for (i = 0; i < num_new; ++i, ++mp, ++entry) {
mp->name = entry->name;
mp->has_arg = entry->type != XTTYPE_NONE;
mp->flag = NULL;
mp->val = entry->id + *offset;
}
/* Third, the old options */
memcpy(mp, oldopts, sizeof(*mp) * num_old);
mp += num_old;
xtables_free_opts(0);
/* Clear trailing entry */
memset(mp, 0, sizeof(*mp));
return merge;
}
/**
* Give the upper limit for a certain type.
*/
static uintmax_t xtopt_max_by_type(enum xt_option_type type)
{
switch (type) {
case XTTYPE_UINT8:
case XTTYPE_UINT8RC:
return UINT8_MAX;
case XTTYPE_UINT16:
case XTTYPE_UINT16RC:
return UINT16_MAX;
case XTTYPE_UINT32:
case XTTYPE_UINT32RC:
return UINT32_MAX;
case XTTYPE_UINT64:
case XTTYPE_UINT64RC:
return UINT64_MAX;
default:
return 0;
}
}
/**
* Return the size of a single entity based upon a type - predominantly an
* XTTYPE_UINT*RC type.
*/
static size_t xtopt_esize_by_type(enum xt_option_type type)
{
switch (type) {
case XTTYPE_UINT8RC:
return xtopt_psize[XTTYPE_UINT8];
case XTTYPE_UINT16RC:
return xtopt_psize[XTTYPE_UINT16];
case XTTYPE_UINT32RC:
return xtopt_psize[XTTYPE_UINT32];
case XTTYPE_UINT64RC:
return xtopt_psize[XTTYPE_UINT64];
default:
return xtopt_psize[type];
}
}
/**
* Require a simple integer.
*/
static void xtopt_parse_int(struct xt_option_call *cb)
{
const struct xt_option_entry *entry = cb->entry;
uintmax_t lmin = 0, lmax = xtopt_max_by_type(entry->type);
uintmax_t value;
if (cb->entry->min != 0)
lmin = cb->entry->min;
if (cb->entry->max != 0)
lmax = cb->entry->max;
if (!xtables_strtoul(cb->arg, NULL, &value, lmin, lmax))
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: bad value for option \"--%s\", "
"or out of range (%ju-%ju).\n",
cb->ext_name, entry->name, lmin, lmax);
if (entry->type == XTTYPE_UINT8) {
cb->val.u8 = value;
if (entry->flags & XTOPT_PUT)
*(uint8_t *)XTOPT_MKPTR(cb) = cb->val.u8;
} else if (entry->type == XTTYPE_UINT16) {
cb->val.u16 = value;
if (entry->flags & XTOPT_PUT)
*(uint16_t *)XTOPT_MKPTR(cb) = cb->val.u16;
} else if (entry->type == XTTYPE_UINT32) {
cb->val.u32 = value;
if (entry->flags & XTOPT_PUT)
*(uint32_t *)XTOPT_MKPTR(cb) = cb->val.u32;
} else if (entry->type == XTTYPE_UINT64) {
cb->val.u64 = value;
if (entry->flags & XTOPT_PUT)
*(uint64_t *)XTOPT_MKPTR(cb) = cb->val.u64;
}
}
/**
* Require a simple floating point number.
*/
static void xtopt_parse_float(struct xt_option_call *cb)
{
const struct xt_option_entry *entry = cb->entry;
double value;
char *end;
value = strtod(cb->arg, &end);
if (end == cb->arg || *end != '\0' ||
(entry->min != entry->max &&
(value < entry->min || value > entry->max)))
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: bad value for option \"--%s\", "
"or out of range (%u-%u).\n",
cb->ext_name, entry->name, entry->min, entry->max);
cb->val.dbl = value;
if (entry->flags & XTOPT_PUT)
*(double *)XTOPT_MKPTR(cb) = cb->val.dbl;
}
/**
* Copy the parsed value to the appropriate entry in cb->val.
*/
static void xtopt_mint_value_to_cb(struct xt_option_call *cb, uintmax_t value)
{
const struct xt_option_entry *entry = cb->entry;
if (cb->nvals >= ARRAY_SIZE(cb->val.u32_range))
return;
if (entry->type == XTTYPE_UINT8RC)
cb->val.u8_range[cb->nvals] = value;
else if (entry->type == XTTYPE_UINT16RC)
cb->val.u16_range[cb->nvals] = value;
else if (entry->type == XTTYPE_UINT32RC)
cb->val.u32_range[cb->nvals] = value;
else if (entry->type == XTTYPE_UINT64RC)
cb->val.u64_range[cb->nvals] = value;
}
/**
* Copy the parsed value to the data area, using appropriate type access.
*/
static void xtopt_mint_value_to_ptr(struct xt_option_call *cb, void **datap,
uintmax_t value)
{
const struct xt_option_entry *entry = cb->entry;
void *data = *datap;
if (!(entry->flags & XTOPT_PUT))
return;
if (entry->type == XTTYPE_UINT8RC)
*(uint8_t *)data = value;
else if (entry->type == XTTYPE_UINT16RC)
*(uint16_t *)data = value;
else if (entry->type == XTTYPE_UINT32RC)
*(uint32_t *)data = value;
else if (entry->type == XTTYPE_UINT64RC)
*(uint64_t *)data = value;
data += xtopt_esize_by_type(entry->type);
*datap = data;
}
/**
* Multiple integer parse routine.
*
* This function is capable of parsing any number of fields. Only the first
* two values from the string will be put into @cb however (and as such,
* @cb->val.uXX_range is just that large) to cater for the few extensions that
* do not have a range[2] field, but {min, max}, and which cannot use
* XTOPT_POINTER.
*/
static void xtopt_parse_mint(struct xt_option_call *cb)
{
const struct xt_option_entry *entry = cb->entry;
const char *arg = cb->arg;
size_t esize = xtopt_esize_by_type(entry->type);
const uintmax_t lmax = xtopt_max_by_type(entry->type);
void *put = XTOPT_MKPTR(cb);
unsigned int maxiter;
uintmax_t value;
char *end = "";
char sep = ':';
maxiter = entry->size / esize;
if (maxiter == 0)
maxiter = ARRAY_SIZE(cb->val.u32_range);
if (entry->size % esize != 0)
xt_params->exit_err(OTHER_PROBLEM, "%s: memory block does "
"not have proper size\n", __func__);
cb->nvals = 0;
for (arg = cb->arg, end = (char *)arg; ; arg = end + 1) {
if (cb->nvals == maxiter)
xt_params->exit_err(PARAMETER_PROBLEM, "%s: Too many "
"components for option \"--%s\" (max: %u)\n",
cb->ext_name, entry->name, maxiter);
if (*arg == '\0' || *arg == sep) {
/* Default range components when field not spec'd. */
end = (char *)arg;
value = (cb->nvals == 1) ? lmax : 0;
} else {
if (!xtables_strtoul(arg, &end, &value, 0, lmax))
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: bad value for option \"--%s\" near "
"\"%s\", or out of range (0-%ju).\n",
cb->ext_name, entry->name, arg, lmax);
if (*end != '\0' && *end != sep)
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: Argument to \"--%s\" has "
"unexpected characters near \"%s\".\n",
cb->ext_name, entry->name, end);
}
xtopt_mint_value_to_cb(cb, value);
++cb->nvals;
xtopt_mint_value_to_ptr(cb, &put, value);
if (*end == '\0')
break;
}
}
static void xtopt_parse_string(struct xt_option_call *cb)
{
const struct xt_option_entry *entry = cb->entry;
size_t z = strlen(cb->arg);
char *p;
if (entry->min != 0 && z < entry->min)
xt_params->exit_err(PARAMETER_PROBLEM,
"Argument must have a minimum length of "
"%u characters\n", entry->min);
if (entry->max != 0 && z > entry->max)
xt_params->exit_err(PARAMETER_PROBLEM,
"Argument must have a maximum length of "
"%u characters\n", entry->max);
if (!(entry->flags & XTOPT_PUT))
return;
if (z >= entry->size)
z = entry->size - 1;
p = XTOPT_MKPTR(cb);
strncpy(p, cb->arg, z);
p[z] = '\0';
}
static const struct tos_symbol_info {
unsigned char value;
const char *name;
} tos_symbol_names[] = {
{IPTOS_LOWDELAY, "Minimize-Delay"},
{IPTOS_THROUGHPUT, "Maximize-Throughput"},
{IPTOS_RELIABILITY, "Maximize-Reliability"},
{IPTOS_MINCOST, "Minimize-Cost"},
{IPTOS_NORMALSVC, "Normal-Service"},
{},
};
/*
* tos_parse_numeric - parse a string like "15/255"
*
* @str: input string
* @tvm: (value/mask) tuple
* @max: maximum allowed value (must be pow(2,some_int)-1)
*/
static bool tos_parse_numeric(const char *str, struct xt_option_call *cb,
unsigned int max)
{
unsigned int value;
char *end;
xtables_strtoui(str, &end, &value, 0, max);
cb->val.tos_value = value;
cb->val.tos_mask = max;
if (*end == '/') {
const char *p = end + 1;
if (!xtables_strtoui(p, &end, &value, 0, max))
xtables_error(PARAMETER_PROBLEM, "Illegal value: \"%s\"",
str);
cb->val.tos_mask = value;
}
if (*end != '\0')
xtables_error(PARAMETER_PROBLEM, "Illegal value: \"%s\"", str);
return true;
}
/**
* @str: input string
* @tvm: (value/mask) tuple
* @def_mask: mask to force when a symbolic name is used
*/
static void xtopt_parse_tosmask(struct xt_option_call *cb)
{
const struct tos_symbol_info *symbol;
char *tmp;
if (xtables_strtoui(cb->arg, &tmp, NULL, 0, UINT8_MAX)) {
tos_parse_numeric(cb->arg, cb, UINT8_MAX);
return;
}
/*
* This is our way we deal with different defaults
* for different revisions.
*/
cb->val.tos_mask = cb->entry->max;
for (symbol = tos_symbol_names; symbol->name != NULL; ++symbol)
if (strcasecmp(cb->arg, symbol->name) == 0) {
cb->val.tos_value = symbol->value;
return;
}
xtables_error(PARAMETER_PROBLEM, "Symbolic name \"%s\" is unknown",
cb->arg);
}
/**
* Validate the input for being conformant to "mark[/mask]".
*/
static void xtopt_parse_markmask(struct xt_option_call *cb)
{
unsigned int mark = 0, mask = ~0U;
char *end;
if (!xtables_strtoui(cb->arg, &end, &mark, 0, UINT32_MAX))
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: bad mark value for option \"--%s\", "
"or out of range.\n",
cb->ext_name, cb->entry->name);
if (*end == '/' &&
!xtables_strtoui(end + 1, &end, &mask, 0, UINT32_MAX))
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: bad mask value for option \"--%s\", "
"or out of range.\n",
cb->ext_name, cb->entry->name);
if (*end != '\0')
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: trailing garbage after value "
"for option \"--%s\".\n",
cb->ext_name, cb->entry->name);
cb->val.mark = mark;
cb->val.mask = mask;
}
static int xtopt_sysloglvl_compare(const void *a, const void *b)
{
const char *name = a;
const struct syslog_level *entry = b;
return strcmp(name, entry->name);
}
static void xtopt_parse_sysloglevel(struct xt_option_call *cb)
{
static const struct syslog_level log_names[] = { /* must be sorted */
{"alert", LOG_ALERT},
{"crit", LOG_CRIT},
{"debug", LOG_DEBUG},
{"emerg", LOG_EMERG},
{"error", LOG_ERR}, /* deprecated */
{"info", LOG_INFO},
{"notice", LOG_NOTICE},
{"panic", LOG_EMERG}, /* deprecated */
{"warning", LOG_WARNING},
};
const struct syslog_level *e;
unsigned int num = 0;
if (!xtables_strtoui(cb->arg, NULL, &num, 0, 7)) {
e = bsearch(cb->arg, log_names, ARRAY_SIZE(log_names),
sizeof(*log_names), xtopt_sysloglvl_compare);
if (e == NULL)
xt_params->exit_err(PARAMETER_PROBLEM,
"log level \"%s\" unknown\n", cb->arg);
num = e->level;
}
cb->val.syslog_level = num;
if (cb->entry->flags & XTOPT_PUT)
*(uint8_t *)XTOPT_MKPTR(cb) = num;
}
static void *xtables_sa_host(const void *sa, unsigned int afproto)
{
if (afproto == AF_INET6)
return &((struct sockaddr_in6 *)sa)->sin6_addr;
else if (afproto == AF_INET)
return &((struct sockaddr_in *)sa)->sin_addr;
return (void *)sa;
}
static socklen_t xtables_sa_hostlen(unsigned int afproto)
{
if (afproto == AF_INET6)
return sizeof(struct in6_addr);
else if (afproto == AF_INET)
return sizeof(struct in_addr);
return 0;
}
/**
* Accepts: a hostname (DNS), or a single inetaddr - without any mask. The
* result is stored in @cb->val.haddr. Additionally, @cb->val.hmask and
* @cb->val.hlen are set for completeness to the appropriate values.
*/
static void xtopt_parse_host(struct xt_option_call *cb)
{
struct addrinfo hints = {.ai_family = afinfo->family};
unsigned int adcount = 0;
struct addrinfo *res, *p;
int ret;
ret = getaddrinfo(cb->arg, NULL, &hints, &res);
if (ret != 0)
xt_params->exit_err(PARAMETER_PROBLEM,
"getaddrinfo: %s\n", gai_strerror(ret));
memset(&cb->val.hmask, 0xFF, sizeof(cb->val.hmask));
cb->val.hlen = (afinfo->family == NFPROTO_IPV4) ? 32 : 128;
for (p = res; p != NULL; p = p->ai_next) {
if (adcount == 0) {
memset(&cb->val.haddr, 0, sizeof(cb->val.haddr));
memcpy(&cb->val.haddr,
xtables_sa_host(p->ai_addr, p->ai_family),
xtables_sa_hostlen(p->ai_family));
++adcount;
continue;
}
if (memcmp(&cb->val.haddr,
xtables_sa_host(p->ai_addr, p->ai_family),
xtables_sa_hostlen(p->ai_family)) != 0)
xt_params->exit_err(PARAMETER_PROBLEM,
"%s resolves to more than one address\n",
cb->arg);
}
freeaddrinfo(res);
if (cb->entry->flags & XTOPT_PUT)
/* Validation in xtables_option_metavalidate */
memcpy(XTOPT_MKPTR(cb), &cb->val.haddr,
sizeof(cb->val.haddr));
}
/**
* @name: port name, or number as a string (e.g. "http" or "80")
*
* Resolve a port name to a number. Returns the port number in integral
* form on success, or <0 on error. (errno will not be set.)
*/
static int xtables_getportbyname(const char *name)
{
struct addrinfo *res = NULL, *p;
int ret;
ret = getaddrinfo(NULL, name, NULL, &res);
if (ret != 0)
return -1;
ret = -1;
for (p = res; p != NULL; p = p->ai_next) {
if (p->ai_family == AF_INET6) {
ret = ((struct sockaddr_in6 *)p->ai_addr)->sin6_port;
break;
} else if (p->ai_family == AF_INET) {
ret = ((struct sockaddr_in *)p->ai_addr)->sin_port;
break;
}
}
freeaddrinfo(res);
if (ret < 0)
return ret;
return ntohs(ret);
}
/**
* Validate and parse a protocol specification (number or name) by use of
* /etc/protocols and put the result into @cb->val.protocol.
*/
static void xtopt_parse_protocol(struct xt_option_call *cb)
{
cb->val.protocol = xtables_parse_protocol(cb->arg);
if (cb->entry->flags & XTOPT_PUT)
*(uint8_t *)XTOPT_MKPTR(cb) = cb->val.protocol;
}
/**
* Validate and parse a port specification and put the result into
* @cb->val.port.
*/
static void xtopt_parse_port(struct xt_option_call *cb)
{
const struct xt_option_entry *entry = cb->entry;
int ret;
ret = xtables_getportbyname(cb->arg);
if (ret < 0)
xt_params->exit_err(PARAMETER_PROBLEM,
"Port \"%s\" does not resolve to anything.\n",
cb->arg);
if (entry->flags & XTOPT_NBO)
ret = htons(ret);
cb->val.port = ret;
if (entry->flags & XTOPT_PUT)
*(uint16_t *)XTOPT_MKPTR(cb) = cb->val.port;
}
static void xtopt_parse_mport(struct xt_option_call *cb)
{
static const size_t esize = sizeof(uint16_t);
const struct xt_option_entry *entry = cb->entry;
char *lo_arg, *wp_arg, *arg;
unsigned int maxiter;
int value;
wp_arg = lo_arg = strdup(cb->arg);
if (lo_arg == NULL)
xt_params->exit_err(RESOURCE_PROBLEM, "strdup");
maxiter = entry->size / esize;
if (maxiter == 0)
maxiter = 2; /* ARRAY_SIZE(cb->val.port_range) */
if (entry->size % esize != 0)
xt_params->exit_err(OTHER_PROBLEM, "%s: memory block does "
"not have proper size\n", __func__);
cb->val.port_range[0] = 0;
cb->val.port_range[1] = UINT16_MAX;
cb->nvals = 0;
while ((arg = strsep(&wp_arg, ":")) != NULL) {
if (cb->nvals == maxiter)
xt_params->exit_err(PARAMETER_PROBLEM, "%s: Too many "
"components for option \"--%s\" (max: %u)\n",
cb->ext_name, entry->name, maxiter);
if (*arg == '\0') {
++cb->nvals;
continue;
}
value = xtables_getportbyname(arg);
if (value < 0)
xt_params->exit_err(PARAMETER_PROBLEM,
"Port \"%s\" does not resolve to "
"anything.\n", arg);
if (entry->flags & XTOPT_NBO)
value = htons(value);
if (cb->nvals < ARRAY_SIZE(cb->val.port_range))
cb->val.port_range[cb->nvals] = value;
++cb->nvals;
}
if (cb->nvals == 1) {
cb->val.port_range[1] = cb->val.port_range[0];
++cb->nvals;
}
if (entry->flags & XTOPT_PUT)
memcpy(XTOPT_MKPTR(cb), cb->val.port_range, sizeof(uint16_t) *
(cb->nvals <= maxiter ? cb->nvals : maxiter));
free(lo_arg);
}
static int xtopt_parse_mask(struct xt_option_call *cb)
{
struct addrinfo hints = {.ai_family = afinfo->family,
.ai_flags = AI_NUMERICHOST };
struct addrinfo *res;
int ret;
ret = getaddrinfo(cb->arg, NULL, &hints, &res);
if (ret != 0)
return 0;
memcpy(&cb->val.hmask, xtables_sa_host(res->ai_addr, res->ai_family),
xtables_sa_hostlen(res->ai_family));
switch(afinfo->family) {
case AF_INET:
cb->val.hlen = xtables_ipmask_to_cidr(&cb->val.hmask.in);
break;
case AF_INET6:
cb->val.hlen = xtables_ip6mask_to_cidr(&cb->val.hmask.in6);
break;
}
freeaddrinfo(res);
return 1;
}
/**
* Parse an integer and ensure it is within the address family's prefix length
* limits. The result is stored in @cb->val.hlen.
*/
static void xtopt_parse_plen(struct xt_option_call *cb)
{
const struct xt_option_entry *entry = cb->entry;
unsigned int prefix_len = 128; /* happiness is a warm gcc */
cb->val.hlen = (afinfo->family == NFPROTO_IPV4) ? 32 : 128;
if (!xtables_strtoui(cb->arg, NULL, &prefix_len, 0, cb->val.hlen)) {
/* Is this mask expressed in full format? e.g. 255.255.255.0 */
if (xtopt_parse_mask(cb))
return;
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: bad value for option \"--%s\", "
"neither a valid network mask "
"nor valid CIDR (%u-%u).\n",
cb->ext_name, entry->name, 0, cb->val.hlen);
}
cb->val.hlen = prefix_len;
}
/**
* Reuse xtopt_parse_plen for testing the integer. Afterwards convert this to
* a bitmask, and make it available through @cb->val.hmask (hlen remains
* valid). If %XTOPT_PUT is used, hmask will be copied to the target area.
*/
static void xtopt_parse_plenmask(struct xt_option_call *cb)
{
const struct xt_option_entry *entry = cb->entry;
uint32_t *mask = cb->val.hmask.all;
xtopt_parse_plen(cb);
memset(mask, 0xFF, sizeof(union nf_inet_addr));
/* This shifting is AF-independent. */
if (cb->val.hlen == 0) {
mask[0] = mask[1] = mask[2] = mask[3] = 0;
} else if (cb->val.hlen <= 32) {
mask[0] <<= 32 - cb->val.hlen;
mask[1] = mask[2] = mask[3] = 0;
} else if (cb->val.hlen <= 64) {
mask[1] <<= 32 - (cb->val.hlen - 32);
mask[2] = mask[3] = 0;
} else if (cb->val.hlen <= 96) {
mask[2] <<= 32 - (cb->val.hlen - 64);
mask[3] = 0;
} else if (cb->val.hlen <= 128) {
mask[3] <<= 32 - (cb->val.hlen - 96);
}
mask[0] = htonl(mask[0]);
mask[1] = htonl(mask[1]);
mask[2] = htonl(mask[2]);
mask[3] = htonl(mask[3]);
if (entry->flags & XTOPT_PUT)
memcpy(XTOPT_MKPTR(cb), mask, sizeof(union nf_inet_addr));
}
static void xtopt_parse_hostmask(struct xt_option_call *cb)
{
const char *orig_arg = cb->arg;
char *work, *p;
if (strchr(cb->arg, '/') == NULL) {
xtopt_parse_host(cb);
return;
}
work = strdup(orig_arg);
if (work == NULL)
xt_params->exit_err(PARAMETER_PROBLEM, "strdup");
p = strchr(work, '/'); /* by def this can't be NULL now */
*p++ = '\0';
/*
* Because xtopt_parse_host and xtopt_parse_plenmask would store
* different things in the same target area, XTTYPE_HOSTMASK must
* disallow XTOPT_PUT, which it does by forcing its absence,
* cf. not being listed in xtopt_psize.
*/
cb->arg = work;
xtopt_parse_host(cb);
cb->arg = p;
xtopt_parse_plenmask(cb);
cb->arg = orig_arg;
}
static void xtopt_parse_ethermac(struct xt_option_call *cb)
{
const char *arg = cb->arg;
unsigned int i;
char *end;
for (i = 0; i < ARRAY_SIZE(cb->val.ethermac) - 1; ++i) {
cb->val.ethermac[i] = strtoul(arg, &end, 16);
if (*end != ':' || end - arg > 2)
goto out;
arg = end + 1;
}
i = ARRAY_SIZE(cb->val.ethermac) - 1;
cb->val.ethermac[i] = strtoul(arg, &end, 16);
if (*end != '\0' || end - arg > 2)
goto out;
if (cb->entry->flags & XTOPT_PUT)
memcpy(XTOPT_MKPTR(cb), cb->val.ethermac,
sizeof(cb->val.ethermac));
return;
out:
xt_params->exit_err(PARAMETER_PROBLEM, "Invalid MAC address specified.");
}
static void (*const xtopt_subparse[])(struct xt_option_call *) = {
[XTTYPE_UINT8] = xtopt_parse_int,
[XTTYPE_UINT16] = xtopt_parse_int,
[XTTYPE_UINT32] = xtopt_parse_int,
[XTTYPE_UINT64] = xtopt_parse_int,
[XTTYPE_UINT8RC] = xtopt_parse_mint,
[XTTYPE_UINT16RC] = xtopt_parse_mint,
[XTTYPE_UINT32RC] = xtopt_parse_mint,
[XTTYPE_UINT64RC] = xtopt_parse_mint,
[XTTYPE_DOUBLE] = xtopt_parse_float,
[XTTYPE_STRING] = xtopt_parse_string,
[XTTYPE_TOSMASK] = xtopt_parse_tosmask,
[XTTYPE_MARKMASK32] = xtopt_parse_markmask,
[XTTYPE_SYSLOGLEVEL] = xtopt_parse_sysloglevel,
[XTTYPE_HOST] = xtopt_parse_host,
[XTTYPE_HOSTMASK] = xtopt_parse_hostmask,
[XTTYPE_PROTOCOL] = xtopt_parse_protocol,
[XTTYPE_PORT] = xtopt_parse_port,
[XTTYPE_PORTRC] = xtopt_parse_mport,
[XTTYPE_PLEN] = xtopt_parse_plen,
[XTTYPE_PLENMASK] = xtopt_parse_plenmask,
[XTTYPE_ETHERMAC] = xtopt_parse_ethermac,
};
/**
* The master option parsing routine. May be used for the ".x6_parse"
* function pointer in extensions if fully automatic parsing is desired.
* It may be also called manually from a custom x6_parse function.
*/
void xtables_option_parse(struct xt_option_call *cb)
{
const struct xt_option_entry *entry = cb->entry;
unsigned int eflag = 1 << cb->entry->id;
/*
* With {.id = P_FOO, .excl = P_FOO} we can have simple double-use
* prevention. Though it turned out that this is too much typing (most
* of the options are one-time use only), so now we also have
* %XTOPT_MULTI.
*/
if ((!(entry->flags & XTOPT_MULTI) || (entry->excl & eflag)) &&
cb->xflags & eflag)
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: option \"--%s\" can only be used once.\n",
cb->ext_name, cb->entry->name);
if (cb->invert && !(entry->flags & XTOPT_INVERT))
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: option \"--%s\" cannot be inverted.\n",
cb->ext_name, entry->name);
if (entry->type != XTTYPE_NONE && optarg == NULL)
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: option \"--%s\" requires an argument.\n",
cb->ext_name, entry->name);
/*
* Fill in fallback value for "nvals", in case an extension (as it
* happened with libxt_conntrack.2) tries to read it, despite not using
* a *RC option type.
*/
cb->nvals = 1;
if (entry->type <= ARRAY_SIZE(xtopt_subparse) &&
xtopt_subparse[entry->type] != NULL)
xtopt_subparse[entry->type](cb);
/* Exclusion with other flags tested later in finalize. */
cb->xflags |= 1 << entry->id;
}
/**
* Verifies that an extension's option map descriptor is valid, and ought to
* be called right after the extension has been loaded, and before option
* merging/xfrm.
*/
void xtables_option_metavalidate(const char *name,
const struct xt_option_entry *entry)
{
for (; entry->name != NULL; ++entry) {
if (entry->id >= CHAR_BIT * sizeof(unsigned int) ||
entry->id >= XT_OPTION_OFFSET_SCALE)
xt_params->exit_err(OTHER_PROBLEM,
"Extension %s uses invalid ID %u\n",
name, entry->id);
if (!(entry->flags & XTOPT_PUT)) {
if (entry->ptroff != 0)
xt_params->exit_err(OTHER_PROBLEM,
"%s: ptroff for \"--%s\" is non-"
"zero but no XTOPT_PUT is specified. "
"Oversight?", name, entry->name);
continue;
}
if (entry->type >= ARRAY_SIZE(xtopt_psize) ||
xtopt_psize[entry->type] == 0)
xt_params->exit_err(OTHER_PROBLEM,
"%s: entry type of option \"--%s\" cannot be "
"combined with XTOPT_PUT\n",
name, entry->name);
if (xtopt_psize[entry->type] != -1 &&
xtopt_psize[entry->type] != entry->size)
xt_params->exit_err(OTHER_PROBLEM,
"%s: option \"--%s\" points to a memory block "
"of wrong size (expected %zu, got %zu)\n",
name, entry->name,
xtopt_psize[entry->type], entry->size);
}
}
/**
* Find an option entry by its id.
*/
static const struct xt_option_entry *
xtables_option_lookup(const struct xt_option_entry *entry, unsigned int id)
{
for (; entry->name != NULL; ++entry)
if (entry->id == id)
return entry;
return NULL;
}
/**
* @c: getopt id (i.e. with offset)
* @fw: struct ipt_entry or ip6t_entry
*
* Dispatch arguments to the appropriate parse function, based upon the
* extension's choice of API.
*/
void xtables_option_tpcall(unsigned int c, char **argv, bool invert,
struct xtables_target *t, void *fw)
{
struct xt_option_call cb;
if (t->x6_parse == NULL) {
if (t->parse != NULL)
t->parse(c - t->option_offset, argv, invert,
&t->tflags, fw, &t->t);
return;
}
c -= t->option_offset;
cb.entry = xtables_option_lookup(t->x6_options, c);
if (cb.entry == NULL)
xtables_error(OTHER_PROBLEM,
"Extension does not know id %u\n", c);
cb.arg = optarg;
cb.invert = invert;
cb.ext_name = t->name;
cb.data = t->t->data;
cb.xflags = t->tflags;
cb.target = &t->t;
cb.xt_entry = fw;
cb.udata = t->udata;
t->x6_parse(&cb);
t->tflags = cb.xflags;
}
/**
* @c: getopt id (i.e. with offset)
* @fw: struct ipt_entry or ip6t_entry
*
* Dispatch arguments to the appropriate parse function, based upon the
* extension's choice of API.
*/
void xtables_option_mpcall(unsigned int c, char **argv, bool invert,
struct xtables_match *m, void *fw)
{
struct xt_option_call cb;
if (m->x6_parse == NULL) {
if (m->parse != NULL)
m->parse(c - m->option_offset, argv, invert,
&m->mflags, fw, &m->m);
return;
}
c -= m->option_offset;
cb.entry = xtables_option_lookup(m->x6_options, c);
if (cb.entry == NULL)
xtables_error(OTHER_PROBLEM,
"Extension does not know id %u\n", c);
cb.arg = optarg;
cb.invert = invert;
cb.ext_name = m->name;
cb.data = m->m->data;
cb.xflags = m->mflags;
cb.match = &m->m;
cb.xt_entry = fw;
cb.udata = m->udata;
m->x6_parse(&cb);
m->mflags = cb.xflags;
}
/**
* @name: name of extension
* @entry: current option (from all ext's entries) being validated
* @xflags: flags the extension has collected
* @i: conflicting option (id) to test for
*/
static void
xtables_option_fcheck2(const char *name, const struct xt_option_entry *entry,
const struct xt_option_entry *other,
unsigned int xflags)
{
unsigned int ef = 1 << entry->id, of = 1 << other->id;
if (entry->also & of && !(xflags & of))
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: option \"--%s\" also requires \"--%s\".\n",
name, entry->name, other->name);
if (!(entry->excl & of))
/* Use of entry does not collide with other option, good. */
return;
if ((xflags & (ef | of)) != (ef | of))
/* Conflicting options were not used. */
return;
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: option \"--%s\" cannot be used together with \"--%s\".\n",
name, entry->name, other->name);
}
/**
* @name: name of extension
* @xflags: accumulated flags
* @entry: extension's option table
*
* Check that all option constraints have been met. This effectively replaces
* ->final_check of the older API.
*/
void xtables_options_fcheck(const char *name, unsigned int xflags,
const struct xt_option_entry *table)
{
const struct xt_option_entry *entry, *other;
unsigned int i;
for (entry = table; entry->name != NULL; ++entry) {
if (entry->flags & XTOPT_MAND &&
!(xflags & (1 << entry->id)))
xt_params->exit_err(PARAMETER_PROBLEM,
"%s: option \"--%s\" must be specified\n",
name, entry->name);
if (!(xflags & (1 << entry->id)))
/* Not required, not specified, thus skip. */
continue;
for (i = 0; i < CHAR_BIT * sizeof(entry->id); ++i) {
if (entry->id == i)
/*
* Avoid conflict with self. Multi-use check
* was done earlier in xtables_option_parse.
*/
continue;
other = xtables_option_lookup(table, i);
if (other == NULL)
continue;
xtables_option_fcheck2(name, entry, other, xflags);
}
}
}
/**
* Dispatch arguments to the appropriate final_check function, based upon the
* extension's choice of API.
*/
void xtables_option_tfcall(struct xtables_target *t)
{
if (t->x6_fcheck != NULL) {
struct xt_fcheck_call cb;
cb.ext_name = t->name;
cb.data = t->t->data;
cb.xflags = t->tflags;
cb.udata = t->udata;
t->x6_fcheck(&cb);
} else if (t->final_check != NULL) {
t->final_check(t->tflags);
}
if (t->x6_options != NULL)
xtables_options_fcheck(t->name, t->tflags, t->x6_options);
}
/**
* Dispatch arguments to the appropriate final_check function, based upon the
* extension's choice of API.
*/
void xtables_option_mfcall(struct xtables_match *m)
{
if (m->x6_fcheck != NULL) {
struct xt_fcheck_call cb;
cb.ext_name = m->name;
cb.data = m->m->data;
cb.xflags = m->mflags;
cb.udata = m->udata;
m->x6_fcheck(&cb);
} else if (m->final_check != NULL) {
m->final_check(m->mflags);
}
if (m->x6_options != NULL)
xtables_options_fcheck(m->name, m->mflags, m->x6_options);
}
struct xtables_lmap *xtables_lmap_init(const char *file)
{
struct xtables_lmap *lmap_head = NULL, *lmap_prev = NULL, *lmap_this;
char buf[512];
FILE *fp;
char *cur, *nxt;
int id;
fp = fopen(file, "re");
if (fp == NULL)
return NULL;
while (fgets(buf, sizeof(buf), fp) != NULL) {
cur = buf;
while (isspace(*cur))
++cur;
if (*cur == '#' || *cur == '\n' || *cur == '\0')
continue;
/* iproute2 allows hex and dec format */
errno = 0;
id = strtoul(cur, &nxt, strncmp(cur, "0x", 2) == 0 ? 16 : 10);
if (nxt == cur || errno != 0)
continue;
/* same boundaries as in iproute2 */
if (id < 0 || id > 255)
continue;
cur = nxt;
if (!isspace(*cur))
continue;
while (isspace(*cur))
++cur;
if (*cur == '#' || *cur == '\n' || *cur == '\0')
continue;
nxt = cur;
while (*nxt != '\0' && !isspace(*nxt))
++nxt;
if (nxt == cur)
continue;
*nxt = '\0';
/* found valid data */
lmap_this = malloc(sizeof(*lmap_this));
if (lmap_this == NULL) {
perror("malloc");
goto out;
}
lmap_this->id = id;
lmap_this->name = strdup(cur);
if (lmap_this->name == NULL) {
free(lmap_this);
goto out;
}
lmap_this->next = NULL;
if (lmap_prev != NULL)
lmap_prev->next = lmap_this;
else
lmap_head = lmap_this;
lmap_prev = lmap_this;
}
fclose(fp);
return lmap_head;
out:
fclose(fp);
xtables_lmap_free(lmap_head);
return NULL;
}
void xtables_lmap_free(struct xtables_lmap *head)
{
struct xtables_lmap *next;
for (; head != NULL; head = next) {
next = head->next;
free(head->name);
free(head);
}
}
int xtables_lmap_name2id(const struct xtables_lmap *head, const char *name)
{
for (; head != NULL; head = head->next)
if (strcmp(head->name, name) == 0)
return head->id;
return -1;
}
const char *xtables_lmap_id2name(const struct xtables_lmap *head, int id)
{
for (; head != NULL; head = head->next)
if (head->id == id)
return head->name;
return NULL;
}