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74f611581e
tor/src/or/routerparse.c
Nick Mathewson 80365b9897 Allow multiple exit policy lines; mostly add support for AP policies 
svn:r1905
2004-05-20 02:42:50 +00:00

1071 lines
31 KiB
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/* Copyright 2001-2003 Roger Dingledine, Matej Pfajfar. */
/* See LICENSE for licensing information */
/* $Id$ */
/**
* \file routerparse.c
*
* \brief Code to parse and validate router descriptors and directories.
**/
/* This is required on rh7 to make strptime not complain.
*/
#define _GNU_SOURCE
#include "or.h"
/****************************************************************************/
/** Enumeration of possible token types. The ones starting with K_
* correspond to directory 'keywords'. _UNRECOGNIZED is for an
* unrecognized keyword; _ERR is an error in the tokenizing process,
* _EOF is an end-of-file marker, and _NIL is used to encode
* not-a-token.
*/
typedef enum {
K_ACCEPT,
K_DIRECTORY_SIGNATURE,
K_RECOMMENDED_SOFTWARE,
K_REJECT,
K_ROUTER,
K_SIGNED_DIRECTORY,
K_SIGNING_KEY,
K_ONION_KEY,
K_LINK_KEY, /* XXXX obsolete; remove in June. */
K_ROUTER_SIGNATURE,
K_PUBLISHED,
K_RUNNING_ROUTERS,
K_PLATFORM,
K_OPT,
K_BANDWIDTH,
K_PORTS,
_UNRECOGNIZED,
_ERR,
_EOF,
_NIL
} directory_keyword;
/** Structure to hold a single directory token.
*
* We parse a directory by breaking it into "tokens", each consisting
* of a keyword, a line full of arguments, and a binary object. The
* arguments and object are both optional, depending on the keyword
* type.
*/
typedef struct directory_token_t {
directory_keyword tp; /**< Type of the token. */
int n_args; /**< Number of elements in args */
char **args; /**< Array of arguments from keyword line. */
char *object_type; /**< -----BEGIN [object_type]-----*/
int object_size; /**< Bytes in object_body */
char *object_body; /**< Contents of object, base64-decoded. */
crypto_pk_env_t *key; /**< For public keys only. */
char *error; /**< For _ERR tokens only. */
} directory_token_t;
/* ********************************************************************** */
/** We use a table of rules to decide how to parse each token type. */
/** Rules for how many arguments a keyword can take. */
typedef enum {
NO_ARGS, /**< (1) no arguments, ever */
ARGS, /**< (2) a list of arguments separated by spaces */
CONCAT_ARGS, /**< or (3) the rest of the line, treated as a single argument. */
} arg_syntax;
/** Rules for whether the keyword needs an object. */
typedef enum {
NO_OBJ, /**< (1) no object, ever */
NEED_OBJ, /**< (2) object is required */
NEED_KEY, /**< (3) object is required, and must be a public key. */
OBJ_OK, /**< or (4) object is optional. */
} obj_syntax;
/** Rules for where a keyword can appear. */
typedef enum {
ANY = 0, /**< Appears in router descriptor or in directory sections. */
DIR_ONLY, /**< Appears only in directory. */
RTR_ONLY, /**< Appears only in router descriptor. */
} where_syntax;
/** Table mapping keywords to token value and to argument rules. */
static struct {
char *t; int v; arg_syntax s; obj_syntax os; where_syntax ws;
} token_table[] = {
{ "accept", K_ACCEPT, ARGS, NO_OBJ, RTR_ONLY },
{ "directory-signature", K_DIRECTORY_SIGNATURE, ARGS, NEED_OBJ,DIR_ONLY},
{ "reject", K_REJECT, ARGS, NO_OBJ, RTR_ONLY },
{ "router", K_ROUTER, ARGS, NO_OBJ, RTR_ONLY },
{ "recommended-software",K_RECOMMENDED_SOFTWARE,ARGS, NO_OBJ, DIR_ONLY },
{ "signed-directory", K_SIGNED_DIRECTORY, NO_ARGS, NO_OBJ, DIR_ONLY },
{ "signing-key", K_SIGNING_KEY, NO_ARGS, NEED_KEY,RTR_ONLY },
{ "onion-key", K_ONION_KEY, NO_ARGS, NEED_KEY,RTR_ONLY },
{ "link-key", K_LINK_KEY, NO_ARGS, NEED_KEY,RTR_ONLY },
{ "router-signature", K_ROUTER_SIGNATURE, NO_ARGS, NEED_OBJ,RTR_ONLY },
{ "running-routers", K_RUNNING_ROUTERS, ARGS, NO_OBJ, DIR_ONLY },
{ "ports", K_PORTS, ARGS, NO_OBJ, RTR_ONLY },
{ "bandwidth", K_BANDWIDTH, ARGS, NO_OBJ, RTR_ONLY },
{ "platform", K_PLATFORM, CONCAT_ARGS, NO_OBJ, RTR_ONLY },
{ "published", K_PUBLISHED, CONCAT_ARGS, NO_OBJ, ANY },
{ "opt", K_OPT, CONCAT_ARGS, OBJ_OK, ANY },
{ NULL, -1 }
};
/* static function prototypes */
static int router_add_exit_policy(routerinfo_t *router,directory_token_t *tok);
static struct exit_policy_t *router_parse_exit_policy(directory_token_t *tok);
static int router_get_hash_impl(const char *s, char *digest,
const char *start_str, const char *end_str);
static void token_free(directory_token_t *tok);
static smartlist_t *find_all_exitpolicy(smartlist_t *s);
static directory_token_t *find_first_by_keyword(smartlist_t *s,
directory_keyword keyword);
static int tokenize_string(const char *start, const char *end,
smartlist_t *out, int is_dir);
static directory_token_t *get_next_token(const char **s, where_syntax where);
/** Set <b>digest</b> to the SHA-1 digest of the hash of the directory in
* <b>s</b>. Return 0 on success, nonzero on failure.
*/
int router_get_dir_hash(const char *s, char *digest)
{
return router_get_hash_impl(s,digest,
"signed-directory","directory-signature");
}
/** Set <b>digest</b> to the SHA-1 digest of the hash of the first router in
* <b>s</b>. Return 0 on success, nonzero on failure.
*/
int router_get_router_hash(const char *s, char *digest)
{
return router_get_hash_impl(s,digest,
"router ","router-signature");
}
/** Parse a date of the format "YYYY-MM-DD hh:mm:ss" and store the result into
* *<b>t</b>.
*/
/* XXX this should go in util.c, yes? -RD */
static int parse_time(const char *cp, time_t *t)
{
struct tm st_tm;
#ifdef HAVE_STRPTIME
if (!strptime(cp, "%Y-%m-%d %H:%M:%S", &st_tm)) {
log_fn(LOG_WARN, "Published time was unparseable"); return -1;
}
#else
unsigned int year=0, month=0, day=0, hour=100, minute=100, second=100;
if (sscanf(cp, "%u-%u-%u %u:%u:%u", &year, &month,
&day, &hour, &minute, &second) < 6) {
log_fn(LOG_WARN, "Published time was unparseable"); return -1;
}
if (year < 1970 || month < 1 || month > 12 || day < 1 || day > 31 ||
hour > 23 || minute > 59 || second > 61) {
log_fn(LOG_WARN, "Published time was nonsensical"); return -1;
}
st_tm.tm_year = year;
st_tm.tm_mon = month-1;
st_tm.tm_mday = day;
st_tm.tm_hour = hour;
st_tm.tm_min = minute;
st_tm.tm_sec = second;
#endif
*t = tor_timegm(&st_tm);
return 0;
}
/** Parse a directory from <b>s</b> and, when done, store the
* resulting routerlist in *<b>dest</b>, freeing the old value if necessary.
* If <b>pkey</b> is provided, we check the directory signature with pkey.
*/
int /* Should be static; exposed for unit tests */
router_parse_routerlist_from_directory(const char *str,
routerlist_t **dest,
crypto_pk_env_t *pkey)
{
directory_token_t *tok;
char digest[20];
char signed_digest[128];
routerlist_t *new_dir = NULL;
char *versions = NULL;
time_t published_on;
char *good_nickname_lst[1024];
int n_good_nicknames = 0;
int i, r;
const char *end;
smartlist_t *tokens = NULL;
if (router_get_dir_hash(str, digest)) {
log_fn(LOG_WARN, "Unable to compute digest of directory");
goto err;
}
log(LOG_DEBUG,"Received directory hashes to %s",hex_str(digest,4));
if ((end = strstr(str,"\nrouter "))) {
++end;
} else if ((end = strstr(str, "\ndirectory-signature"))) {
++end;
} else {
end = str + strlen(str);
}
tokens = smartlist_create();
if (tokenize_string(str,end,tokens,1)) {
log_fn(LOG_WARN, "Error tokenizing directory"); goto err;
}
if (smartlist_len(tokens) < 1) {
log_fn(LOG_WARN, "Impossibly short directory header"); goto err;
}
if ((tok = find_first_by_keyword(tokens, _UNRECOGNIZED))) {
log_fn(LOG_WARN, "Unrecognized keyword in \"%s\"; can't parse directory.",
tok->args[0]);
goto err;
}
tok = smartlist_get(tokens,0);
if (tok->tp != K_SIGNED_DIRECTORY) {
log_fn(LOG_WARN, "Directory doesn't start with signed-directory.");
goto err;
}
if (!(tok = find_first_by_keyword(tokens, K_PUBLISHED))) {
log_fn(LOG_WARN, "Missing published time on directory.");
goto err;
}
tor_assert(tok->n_args == 1);
if (parse_time(tok->args[0], &published_on) < 0) {
goto err;
}
if (!(tok = find_first_by_keyword(tokens, K_RECOMMENDED_SOFTWARE))) {
log_fn(LOG_WARN, "Missing recommended-software line from directory.");
goto err;
}
if (tok->n_args != 1) {
log_fn(LOG_WARN, "Invalid recommended-software line"); goto err;
}
versions = tor_strdup(tok->args[0]);
if (!(tok = find_first_by_keyword(tokens, K_RUNNING_ROUTERS))) {
log_fn(LOG_WARN, "Missing running-routers line from directory.");
goto err;
}
n_good_nicknames = tok->n_args;
memcpy(good_nickname_lst, tok->args, n_good_nicknames*sizeof(char *));
tok->n_args = 0; /* Don't free the strings in good_nickname_lst yet. */
/* Read the router list from s, advancing s up past the end of the last
* router. */
str = end;
if (router_parse_list_from_string(&str, &new_dir,
n_good_nicknames,
(const char**)good_nickname_lst)) {
log_fn(LOG_WARN, "Error reading routers from directory");
goto err;
}
for (i = 0; i < n_good_nicknames; ++i) {
tor_free(good_nickname_lst[i]); /* now free them */
}
new_dir->software_versions = versions; versions = NULL;
new_dir->published_on = published_on;
SMARTLIST_FOREACH(tokens, directory_token_t *, tok, token_free(tok));
smartlist_free(tokens);
tokens = smartlist_create();
if (tokenize_string(str,str+strlen(str),tokens,1)<0) {
log_fn(LOG_WARN, "Error tokenizing signature"); goto err;
}
if (smartlist_len(tokens) != 1 ||
((directory_token_t*)smartlist_get(tokens,0))->tp != K_DIRECTORY_SIGNATURE){
log_fn(LOG_WARN,"Expected a single directory signature"); goto err;
}
tok = smartlist_get(tokens,0);
if (strcmp(tok->object_type, "SIGNATURE") || tok->object_size != 128) {
log_fn(LOG_WARN, "Bad object type or length on directory signature");
goto err;
}
if (pkey) {
if (crypto_pk_public_checksig(pkey, tok->object_body, 128, signed_digest)
!= 20) {
log_fn(LOG_WARN, "Error reading directory: invalid signature.");
goto err;
}
log(LOG_DEBUG,"Signed directory hash starts %s", hex_str(signed_digest,4));
if (memcmp(digest, signed_digest, 20)) {
log_fn(LOG_WARN, "Error reading directory: signature does not match.");
goto err;
}
}
if (*dest)
routerlist_free(*dest);
*dest = new_dir;
r = 0;
goto done;
err:
r = -1;
if (new_dir)
routerlist_free(new_dir);
tor_free(versions);
for (i = 0; i < n_good_nicknames; ++i) {
tor_free(good_nickname_lst[i]);
}
done:
if (tokens) {
SMARTLIST_FOREACH(tokens, directory_token_t *, tok, token_free(tok));
smartlist_free(tokens);
}
return r;
}
/** Given a string *<b>s</b> containing a concatenated
* sequence of router descriptors, parses them and stores the result
* in *<b>dest</b>. If good_nickname_lst is provided, then routers whose
* nicknames are not listed are marked as nonrunning. Advances *s to
* a point immediately following the last router entry. Returns 0 on
* success and -1 on failure.
*/
int
router_parse_list_from_string(const char **s, routerlist_t **dest,
int n_good_nicknames,
const char **good_nickname_lst)
{
routerinfo_t *router;
smartlist_t *routers;
int rarray_len = 0;
int i;
const char *end;
tor_assert(s && *s);
routers = smartlist_create();
while (1) {
*s = eat_whitespace(*s);
/* Don't start parsing the rest of *s unless it contains a router. */
if (strncmp(*s, "router ", 7)!=0)
break;
if ((end = strstr(*s+1, "\nrouter "))) {
end++;
} else if ((end = strstr(*s+1, "\ndirectory-signature"))) {
end++;
} else {
end = *s+strlen(*s);
}
router = router_parse_entry_from_string(*s, end);
*s = end;
if (!router) {
log_fn(LOG_WARN, "Error reading router; skipping");
continue;
}
if (n_good_nicknames>=0) {
router->is_running = 0;
for (i = 0; i < n_good_nicknames; ++i) {
if (0==strcasecmp(good_nickname_lst[i], router->nickname)) {
router->is_running = 1;
break;
}
}
} else {
router->is_running = 1; /* start out assuming all dirservers are up */
}
smartlist_add(routers, router);
log_fn(LOG_DEBUG,"just added router #%d.",rarray_len);
}
if (*dest)
routerlist_free(*dest);
*dest = tor_malloc(sizeof(routerlist_t));
(*dest)->routers = routers;
(*dest)->software_versions = NULL;
return 0;
}
/** Helper function: reads a single router entry from *<b>s</b> ...
* *<b>end</b>. Mallocs a new router and returns it if all goes well, else
* returns NULL.
*/
routerinfo_t *router_parse_entry_from_string(const char *s,
const char *end) {
routerinfo_t *router = NULL;
char signed_digest[128];
char digest[128];
smartlist_t *tokens = NULL, *exit_policy_tokens = NULL;
directory_token_t *tok;
int t;
int ports_set, bw_set;
if (!end) {
end = s + strlen(s);
}
if (router_get_router_hash(s, digest) < 0) {
log_fn(LOG_WARN, "Couldn't compute router hash.");
return NULL;
}
tokens = smartlist_create();
if (tokenize_string(s,end,tokens,0)) {
log_fn(LOG_WARN, "Error tokeninzing router descriptor."); goto err;
}
if (smartlist_len(tokens) < 2) {
log_fn(LOG_WARN, "Impossibly short router descriptor.");
goto err;
}
if ((tok = find_first_by_keyword(tokens, _UNRECOGNIZED))) {
log_fn(LOG_WARN, "Unrecognized keyword in \"%s\"; skipping descriptor.",
tok->args[0]);
goto err;
}
tok = smartlist_get(tokens,0);
if (tok->tp != K_ROUTER) {
log_fn(LOG_WARN,"Entry does not start with \"router\"");
goto err;
}
router = tor_malloc_zero(sizeof(routerinfo_t));
router->onion_pkey = router->identity_pkey = NULL;
ports_set = bw_set = 0;
if (tok->n_args == 2 || tok->n_args == 5 || tok->n_args == 6) {
router->nickname = tor_strdup(tok->args[0]);
if (strlen(router->nickname) > MAX_NICKNAME_LEN) {
log_fn(LOG_WARN,"Router nickname too long.");
goto err;
}
if (strspn(router->nickname, LEGAL_NICKNAME_CHARACTERS) !=
strlen(router->nickname)) {
log_fn(LOG_WARN, "Router nickname contains illegal characters.");
goto err;
}
router->address = tor_strdup(tok->args[1]);
router->addr = 0;
if (tok->n_args >= 5) {
router->or_port = atoi(tok->args[2]);
router->socks_port = atoi(tok->args[3]);
router->dir_port = atoi(tok->args[4]);
ports_set = 1;
/* XXXX Remove this after everyone has moved to 0.0.6 */
if (tok->n_args == 6) {
router->bandwidthrate = atoi(tok->args[5]);
router->bandwidthburst = router->bandwidthrate * 10;
bw_set = 1;
}
}
} else {
log_fn(LOG_WARN,"Wrong # of arguments to \"router\" (%d)",tok->n_args);
goto err;
}
tok = find_first_by_keyword(tokens, K_PORTS);
if (tok && ports_set) {
log_fn(LOG_WARN,"Redundant ports line");
goto err;
} else if (tok) {
if (tok->n_args != 3) {
log_fn(LOG_WARN,"Wrong # of arguments to \"ports\"");
goto err;
}
router->or_port = atoi(tok->args[0]);
router->socks_port = atoi(tok->args[1]);
router->dir_port = atoi(tok->args[2]);
ports_set = 1;
}
tok = find_first_by_keyword(tokens, K_BANDWIDTH);
if (tok && bw_set) {
log_fn(LOG_WARN,"Redundant bandwidth line");
goto err;
} else if (tok) {
if (tok->n_args < 2) {
log_fn(LOG_WARN,"Not enough arguments to \"bandwidth\"");
goto err;
}
router->bandwidthrate = atoi(tok->args[0]);
router->bandwidthburst = atoi(tok->args[1]);
bw_set = 1;
}
if (!(tok = find_first_by_keyword(tokens, K_PUBLISHED))) {
log_fn(LOG_WARN, "Missing published time"); goto err;
}
tor_assert(tok->n_args == 1);
if (parse_time(tok->args[0], &router->published_on) < 0)
goto err;
if (!(tok = find_first_by_keyword(tokens, K_ONION_KEY))) {
log_fn(LOG_WARN, "Missing onion key"); goto err;
}
/* XXX Check key length */
router->onion_pkey = tok->key;
tok->key = NULL; /* Prevent free */
if ((tok = find_first_by_keyword(tokens, K_LINK_KEY))) {
log_fn(LOG_INFO, "Skipping obsolete link-key");
}
if (!(tok = find_first_by_keyword(tokens, K_SIGNING_KEY))) {
log_fn(LOG_WARN, "Missing onion key"); goto err;
}
/* XXX Check key length */
router->identity_pkey = tok->key;
tok->key = NULL; /* Prevent free */
if ((tok = find_first_by_keyword(tokens, K_PLATFORM))) {
router->platform = tor_strdup(tok->args[0]);
}
exit_policy_tokens = find_all_exitpolicy(tokens);
SMARTLIST_FOREACH(exit_policy_tokens, directory_token_t *, t,
if (router_add_exit_policy(router,t)<0) {
log_fn(LOG_WARN,"Error in exit policy"); goto err;}
);
if (!(tok = find_first_by_keyword(tokens, K_ROUTER_SIGNATURE))) {
log_fn(LOG_WARN, "Missing router signature"); goto err;
}
if (strcmp(tok->object_type, "SIGNATURE") || tok->object_size != 128) {
log_fn(LOG_WARN, "Bad object type or length on router signature");
goto err;
}
if ((t=crypto_pk_public_checksig(router->identity_pkey, tok->object_body,
128, signed_digest)) != 20) {
log_fn(LOG_WARN, "Invalid signature %d",t); goto err;
}
if (memcmp(digest, signed_digest, 20)) {
log_fn(LOG_WARN, "Mismatched signature"); goto err;
}
if (!ports_set) {
log_fn(LOG_WARN,"No ports declared; failing."); goto err;
}
if (!bw_set) {
log_fn(LOG_WARN,"No bandwidth declared; failing."); goto err;
}
if(!router->or_port) {
log_fn(LOG_WARN,"or_port unreadable or 0. Failing.");
goto err;
}
if (!router->bandwidthrate) {
log_fn(LOG_WARN,"bandwidthrate unreadable or 0. Failing.");
goto err;
}
if (!router->platform) {
router->platform = tor_strdup("<unknown>");
}
log_fn(LOG_DEBUG,"or_port %d, socks_port %d, dir_port %d, bandwidthrate %u, bandwidthburst %u.",
router->or_port, router->socks_port, router->dir_port,
(unsigned) router->bandwidthrate, (unsigned) router->bandwidthburst);
goto done;
return router;
err:
routerinfo_free(router);
router = NULL;
done:
if (tokens) {
SMARTLIST_FOREACH(tokens, directory_token_t *, tok, token_free(tok));
smartlist_free(tokens);
}
if (exit_policy_tokens) {
smartlist_free(exit_policy_tokens);
}
return router;
}
/** Parse the exit policy in the string <b>s</b> and return it.
*/
struct exit_policy_t *
router_parse_exit_policy_from_string(const char *s)
{
directory_token_t *tok = NULL;
const char *cp;
char *tmp;
struct exit_policy_t *r;
int len, idx;
/* *s might not end with \n, so we need to extend it with one. */
len = strlen(s);
cp = tmp = tor_malloc(len+2);
for (idx = 0; idx < len; ++idx) {
tmp[idx] = tolower(s[idx]);
}
tmp[len]='\n';
tmp[len+1]='\0';
tok = get_next_token(&cp, RTR_ONLY);
if (tok->tp == _ERR) {
log_fn(LOG_WARN, "Error reading exit policy: %s", tok->error);
goto err;
}
if (tok->tp != K_ACCEPT && tok->tp != K_REJECT) {
log_fn(LOG_WARN, "Expected 'accept' or 'reject'.");
goto err;
}
/* Now that we've gotten an exit policy, add it to the router. */
r = router_parse_exit_policy(tok);
goto done;
err:
r = NULL;
done:
free(tmp);
token_free(tok);
return r;
}
int router_add_exit_policy_from_string(routerinfo_t *router, const char *s)
{
struct exit_policy_t *newe, *tmpe;
newe = router_parse_exit_policy_from_string(s);
if (!newe)
return -1;
for (tmpe = router->exit_policy; tmpe; tmpe=tmpe->next)
;
tmpe->next = newe;
return 0;
}
static int router_add_exit_policy(routerinfo_t *router,directory_token_t *tok)
{
struct exit_policy_t *newe, **tmpe;
newe = router_parse_exit_policy(tok);
if (!newe)
return -1;
for (tmpe = &router->exit_policy; *tmpe; tmpe=&((*tmpe)->next))
;
*tmpe = newe;
return 0;
}
/** Given a K_ACCEPT or K_REJECT token and a router, create a new exit_policy_t
* corresponding to the token, and add it to <b>router</b> */
static struct exit_policy_t *
router_parse_exit_policy(directory_token_t *tok) {
struct exit_policy_t*newe;
struct in_addr in;
char *arg, *address, *mask, *port, *endptr;
int bits;
tor_assert(tok->tp == K_REJECT || tok->tp == K_ACCEPT);
if (tok->n_args != 1)
return NULL;
arg = tok->args[0];
newe = tor_malloc_zero(sizeof(struct exit_policy_t));
newe->string = tor_malloc(8+strlen(arg));
if (tok->tp == K_REJECT) {
strcpy(newe->string, "reject ");
newe->policy_type = EXIT_POLICY_REJECT;
} else {
strcpy(newe->string, "accept ");
newe->policy_type = EXIT_POLICY_ACCEPT;
}
strcat(newe->string, arg); /* can't overflow */
address = arg;
mask = strchr(arg,'/');
port = strchr(mask?mask:arg,':');
/* Break 'arg' into separate strings. 'arg' was already strdup'd by
* _router_get_next_token, so it's safe to modify.
*/
if (mask)
*mask++ = 0;
if (port)
*port++ = 0;
if (strcmp(address, "*") == 0) {
newe->addr = 0;
} else if (tor_inet_aton(address, &in) != 0) {
newe->addr = ntohl(in.s_addr);
} else {
log_fn(LOG_WARN, "Malformed IP %s in exit policy; rejecting.",
address);
goto policy_read_failed;
}
if (!mask) {
if (strcmp(address, "*") == 0)
newe->msk = 0;
else
newe->msk = 0xFFFFFFFFu;
} else {
endptr = NULL;
bits = (int) strtol(mask, &endptr, 10);
if (!*endptr) {
/* strtol handled the whole mask. */
newe->msk = ~((1<<(32-bits))-1);
} else if (tor_inet_aton(mask, &in) != 0) {
newe->msk = ntohl(in.s_addr);
} else {
log_fn(LOG_WARN, "Malformed mask %s on exit policy; rejecting.",
mask);
goto policy_read_failed;
}
}
if (!port || strcmp(port, "*") == 0) {
newe->prt_min = 0;
newe->prt_max = 65535;
} else {
endptr = NULL;
newe->prt_min = (uint16_t) strtol(port, &endptr, 10);
if (*endptr == '-') {
port = endptr+1;
endptr = NULL;
newe->prt_max = (uint16_t) strtol(port, &endptr, 10);
if (*endptr) {
log_fn(LOG_WARN, "Malformed port %s on exit policy; rejecting.",
port);
}
} else if (*endptr) {
log_fn(LOG_WARN, "Malformed port %s on exit policy; rejecting.",
port);
goto policy_read_failed;
} else {
newe->prt_max = newe->prt_min;
}
}
in.s_addr = htonl(newe->addr);
address = tor_strdup(inet_ntoa(in));
in.s_addr = htonl(newe->msk);
log_fn(LOG_DEBUG,"%s %s/%s:%d-%d",
newe->policy_type == EXIT_POLICY_REJECT ? "reject" : "accept",
address, inet_ntoa(in), newe->prt_min, newe->prt_max);
tor_free(address);
newe->next = NULL;
return newe;
policy_read_failed:
tor_assert(newe->string);
log_fn(LOG_WARN,"Couldn't parse line '%s'. Dropping", newe->string);
tor_free(newe->string);
free(newe);
return NULL;
}
/*
* Low-level tokenizer for router descriptors and directories.
*/
/** Free all resources allocated for <b>tok</b> */
static void
token_free(directory_token_t *tok)
{
int i;
tor_assert(tok);
if (tok->args) {
for (i = 0; i < tok->n_args; ++i) {
tor_free(tok->args[i]);
}
tor_free(tok->args);
}
tor_free(tok->object_type);
tor_free(tok->object_body);
if (tok->key)
crypto_free_pk_env(tok->key);
tor_free(tok);
}
/** Helper function: read the next token from *s, advance *s to the end
* of the token, and return the parsed token. If 'where' is DIR_ONLY
* or RTR_ONLY, reject all tokens of the wrong type.
*/
static directory_token_t *
get_next_token(const char **s, where_syntax where) {
const char *next, *obstart;
int i, done, allocated;
directory_token_t *tok;
arg_syntax a_syn;
obj_syntax o_syn = NO_OBJ;
#define RET_ERR(msg) \
do { if (tok) token_free(tok); \
tok = tor_malloc_zero(sizeof(directory_token_t));\
tok->tp = _ERR; \
tok->error = msg; \
goto done_tokenizing; } while (0)
tok = tor_malloc_zero(sizeof(directory_token_t));
tok->tp = _ERR;
*s = eat_whitespace(*s);
if (!**s) {
tok->tp = _EOF;
return tok;
}
next = find_whitespace(*s);
if (!next) {
tok->error = "Unexpected EOF"; return tok;
}
/* It's a keyword... but which one? */
for (i = 0 ; token_table[i].t ; ++i) {
if (!strncmp(token_table[i].t, *s, next-*s)) {
/* We've found the keyword. */
tok->tp = token_table[i].v;
a_syn = token_table[i].s;
o_syn = token_table[i].os;
if (token_table[i].ws != ANY && token_table[i].ws != where) {
if (where == DIR_ONLY) {
RET_ERR("Found a router-only token in a directory section");
} else {
RET_ERR("Found a directory-only token in a router descriptor");
}
}
if (a_syn == ARGS) {
/* This keyword takes multiple arguments. */
i = 0;
done = (*next == '\n');
allocated = 32;
tok->args = tor_malloc(sizeof(char*)*32);
*s = eat_whitespace_no_nl(next);
while (**s != '\n' && !done) {
next = find_whitespace(*s);
if (*next == '\n')
done = 1;
if (i == allocated) {
allocated *= 2;
tok->args = tor_realloc(tok->args,sizeof(char*)*allocated);
}
tok->args[i++] = tor_strndup(*s,next-*s);
*s = eat_whitespace_no_nl(next+1);
}
tok->n_args = i;
} else if (a_syn == CONCAT_ARGS) {
/* The keyword takes the line as a single argument */
*s = eat_whitespace_no_nl(next);
next = strchr(*s, '\n');
if (!next)
RET_ERR("Unexpected EOF");
tok->args = tor_malloc(sizeof(char*));
tok->args[0] = tor_strndup(*s,next-*s);
tok->n_args = 1;
*s = eat_whitespace_no_nl(next+1);
} else {
/* The keyword takes no arguments. */
tor_assert(a_syn == NO_ARGS);
*s = eat_whitespace_no_nl(next);
if (**s != '\n') {
RET_ERR("Unexpected arguments");
}
tok->n_args = 0;
*s = eat_whitespace_no_nl(*s+1);
}
break;
}
}
if (tok->tp == _ERR) {
tok->tp = _UNRECOGNIZED;
next = strchr(*s, '\n');
if (!next) {
RET_ERR("Unexpected EOF");
}
tok->args = tor_malloc(sizeof(char*));
tok->args[0] = tor_strndup(*s,next-*s);
tok->n_args = 1;
*s = next+1;
o_syn = OBJ_OK;
}
*s = eat_whitespace(*s);
if (strncmp(*s, "-----BEGIN ", 11)) {
goto done_tokenizing;
}
obstart = *s;
*s += 11; /* length of "-----BEGIN ". */
next = strchr(*s, '\n');
if (next-*s < 6 || strncmp(next-5, "-----\n", 6)) {
RET_ERR("Malformed object: bad begin line");
}
tok->object_type = tor_strndup(*s, next-*s-5);
*s = next+1;
next = strstr(*s, "-----END ");
if (!next) {
RET_ERR("Malformed object: missing end line");
}
if (!strcmp(tok->object_type, "RSA PUBLIC KEY")) {
if (strncmp(next, "-----END RSA PUBLIC KEY-----\n", 29))
RET_ERR("Malformed object: mismatched end line");
next = strchr(next,'\n')+1;
tok->key = crypto_new_pk_env();
if (crypto_pk_read_public_key_from_string(tok->key, obstart, next-obstart))
RET_ERR("Couldn't parse public key.");
*s = next;
} else {
tok->object_body = tor_malloc(next-*s); /* really, this is too much RAM. */
i = base64_decode(tok->object_body, 256, *s, next-*s);
if (i<0) {
RET_ERR("Malformed object: bad base64-encoded data");
}
tok->object_size = i;
*s = next + 9; /* length of "-----END ". */
i = strlen(tok->object_type);
if (strncmp(*s, tok->object_type, i) || strncmp(*s+i, "-----\n", 6)) {
RET_ERR("Malformed object: mismatched end tag");
}
*s += i+6;
}
switch(o_syn)
{
case NO_OBJ:
if (tok->object_body)
RET_ERR("Unexpected object for keyword");
if (tok->key)
RET_ERR("Unexpected public key for keyword");
break;
case NEED_OBJ:
if (!tok->object_body)
RET_ERR("Missing object for keyword");
break;
case NEED_KEY:
if (!tok->key)
RET_ERR("Missing publid key for keyword");
break;
case OBJ_OK:
break;
}
done_tokenizing:
#if 0
for (i = 0; token_table[i].t ; ++i) {
if (token_table[i].v == tok->tp) {
fputs(token_table[i].t, stdout);
break;
i = -1;
}
}
if (i) {
if (tok->tp == _UNRECOGNIZED) fputs("UNRECOGNIZED", stdout);
if (tok->tp == _ERR) fputs("ERR",stdout);
if (tok->tp == _EOF) fputs("EOF",stdout);
if (tok->tp == _NIL) fputs("_NIL",stdout);
}
for(i = 0; i < tok->n_args; ++i) {
fprintf(stdout," \"%s\"", tok->args[i]);
}
if (tok->error) { fprintf(stdout," *%s*", tok->error); }
fputs("\n",stdout);
#endif
return tok;
#undef RET_ERR
}
/** Read all tokens from a string between <b>start</b> and <b>end</b>, and add
* them to <b>out</b>. If <b>is_dir</b> is true, reject all non-directory
* tokens; else reject all non-routerdescriptor tokens.
*/
static int
tokenize_string(const char *start, const char *end, smartlist_t *out,
int is_dir)
{
const char **s;
directory_token_t *tok = NULL;
where_syntax where = is_dir ? DIR_ONLY : RTR_ONLY;
s = &start;
while (*s < end && (!tok || tok->tp != _EOF)) {
tok = get_next_token(s, where);
if (tok->tp == _ERR) {
log_fn(LOG_WARN, "parse error: %s", tok->error);
return -1;
}
smartlist_add(out, tok);
*s = eat_whitespace(*s);
}
return 0;
}
/** Find the first token in <b>s</b> whose keyword is <b>keyword</b>; return
* NULL if no such keyword is found.
*/
static directory_token_t *
find_first_by_keyword(smartlist_t *s, directory_keyword keyword)
{
SMARTLIST_FOREACH(s, directory_token_t *, t, if (t->tp == keyword) return t);
return NULL;
}
/** Return a newly allocated smartlist of all accept or reject tokens in
* <b>s</b>.
*/
static smartlist_t *
find_all_exitpolicy(smartlist_t *s)
{
smartlist_t *out = smartlist_create();
SMARTLIST_FOREACH(s, directory_token_t *, t,
if (t->tp == K_ACCEPT || t->tp == K_REJECT)
smartlist_add(out,t));
return out;
}
/** Compute the SHA digest of the substring of <b>s</b> taken from the first
* occurrence of <b>start_str</b> through the first newline after the first
* subsequent occurrence of <b>end_str</b>; store the 20-byte result in
* <b>digest</b>; return 0 on success.
*
* If no such substring exists, return -1.
*/
static int router_get_hash_impl(const char *s, char *digest,
const char *start_str,
const char *end_str)
{
char *start, *end;
start = strstr(s, start_str);
if (!start) {
log_fn(LOG_WARN,"couldn't find \"%s\"",start_str);
return -1;
}
end = strstr(start+strlen(start_str), end_str);
if (!end) {
log_fn(LOG_WARN,"couldn't find \"%s\"",end_str);
return -1;
}
end = strchr(end, '\n');
if (!end) {
log_fn(LOG_WARN,"couldn't find EOL");
return -1;
}
++end;
if (crypto_digest(start, end-start, digest)) {
log_fn(LOG_WARN,"couldn't compute digest");
return -1;
}
return 0;
}
/*
Local Variables:
mode:c
indent-tabs-mode:nil
c-basic-offset:2
End:
*/
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