commit d0068be0ddad3113052b213f5eab4d17211c38b3 Author: Neel Chauhan neel@neelc.org Date: Sat Dec 14 13:16:59 2019 -0500
Allow ed25519 keys to be banned in approved-routers --- src/feature/dirauth/process_descs.c | 197 +++++++++++++++++++++++++----------- src/feature/dirauth/process_descs.h | 55 +++++++++- src/feature/nodelist/routerlist.c | 13 ++- src/feature/relay/router.c | 6 +- 4 files changed, 201 insertions(+), 70 deletions(-)
diff --git a/src/feature/dirauth/process_descs.c b/src/feature/dirauth/process_descs.c index 8dae4e933..37c33b2c7 100644 --- a/src/feature/dirauth/process_descs.c +++ b/src/feature/dirauth/process_descs.c @@ -12,6 +12,8 @@ * them make those decisions. **/
+#define PROCESS_DESCS_PRIVATE + #include "core/or/or.h" #include "feature/dirauth/process_descs.h"
@@ -23,6 +25,7 @@ #include "feature/dirclient/dlstatus.h" #include "feature/dircommon/directory.h" #include "feature/nodelist/describe.h" +#include "feature/nodelist/microdesc.h" #include "feature/nodelist/networkstatus.h" #include "feature/nodelist/nodelist.h" #include "feature/nodelist/routerinfo.h" @@ -34,44 +37,25 @@ #include "core/or/tor_version_st.h" #include "feature/nodelist/extrainfo_st.h" #include "feature/nodelist/node_st.h" +#include "feature/nodelist/microdesc_st.h" #include "feature/nodelist/routerinfo_st.h" #include "feature/nodelist/routerstatus_st.h" +#include "feature/nodelist/vote_routerstatus_st.h"
#include "lib/encoding/confline.h" +#include "lib/crypt_ops/crypto_format.h"
/** How far in the future do we allow a router to get? (seconds) */ #define ROUTER_ALLOW_SKEW (60*60*12)
static void directory_remove_invalid(void); -struct authdir_config_t; static was_router_added_t dirserv_add_extrainfo(extrainfo_t *ei, const char **msg); static uint32_t -dirserv_get_status_impl(const char *fp, const char *nickname, - uint32_t addr, uint16_t or_port, - const char *platform, const char **msg, - int severity); - -/* 1 Historically used to indicate Named */ -#define RTR_INVALID 2 /**< Believed invalid. */ -#define RTR_REJECT 4 /**< We will not publish this router. */ -/* 8 Historically used to avoid using this as a dir. */ -#define RTR_BADEXIT 16 /**< We'll tell clients not to use this as an exit. */ -/* 32 Historically used to indicade Unnamed */ - -/** Target of status_by_digest map. */ -typedef uint32_t rtr_flags_t; - -static void add_fingerprint_to_dir(const char *fp, - struct authdir_config_t *list, - rtr_flags_t add_status); - -/** List of nickname->identity fingerprint mappings for all the routers - * that we name. Used to prevent router impersonation. */ -typedef struct authdir_config_t { - strmap_t *fp_by_name; /**< Map from lc nickname to fingerprint. */ - digestmap_t *status_by_digest; /**< Map from digest to rtr_flags_t. */ -} authdir_config_t; +dirserv_get_status_impl(const char *id_digest, + const ed25519_public_key_t *ed25519_public_key, + const char *nickname, uint32_t addr, uint16_t or_port, + const char *platform, const char **msg, int severity);
/** Should be static; exposed for testing. */ static authdir_config_t *fingerprint_list = NULL; @@ -83,16 +67,35 @@ authdir_config_new(void) authdir_config_t *list = tor_malloc_zero(sizeof(authdir_config_t)); list->fp_by_name = strmap_new(); list->status_by_digest = digestmap_new(); + list->status_by_digest256 = digest256map_new(); return list; }
+#ifdef TOR_UNIT_TESTS + +/** Initialize fingerprint_list to a new authdir_config_t. Used for tests. */ +void +authdir_init_fingerprint_list(void) +{ + fingerprint_list = authdir_config_new(); +} + +/* Return the current fingerprint_list. Used for tests. */ +authdir_config_t * +authdir_return_fingerprint_list(void) +{ + return fingerprint_list; +} + +#endif /* defined(TOR_UNIT_TESTS) */ + /** Add the fingerprint <b>fp</b> to the smartlist of fingerprint_entry_t's * <b>list</b>, or-ing the currently set status flags with * <b>add_status</b>. */ -/* static */ void -add_fingerprint_to_dir(const char *fp, authdir_config_t *list, - rtr_flags_t add_status) +int +add_rsa_fingerprint_to_dir(const char *fp, authdir_config_t *list, + rtr_flags_t add_status) { char *fingerprint; char d[DIGEST_LEN]; @@ -107,7 +110,7 @@ add_fingerprint_to_dir(const char *fp, authdir_config_t *list, log_warn(LD_DIRSERV, "Couldn't decode fingerprint "%s"", escaped(fp)); tor_free(fingerprint); - return; + return -1; }
status = digestmap_get(list->status_by_digest, d); @@ -118,13 +121,41 @@ add_fingerprint_to_dir(const char *fp, authdir_config_t *list,
tor_free(fingerprint); *status |= add_status; - return; + return 0; +} + +/** Add the ed25519 key <b>edkey</b> to the smartlist of fingerprint_entry_t's + * <b>list</b>, or-ing the currently set status flags with <b>add_status</b>. + * Return -1 if we were unable to decode the key, else return 0. + */ +int +add_ed25519_to_dir(const ed25519_public_key_t *edkey, authdir_config_t *list, + rtr_flags_t add_status) +{ + rtr_flags_t *status; + + tor_assert(edkey); + tor_assert(list); + + if (ed25519_validate_pubkey(edkey) < 0) { + log_warn(LD_DIRSERV, "Invalid ed25519 key "%s"", ed25519_fmt(edkey)); + return -1; + } + + status = digest256map_get(list->status_by_digest256, edkey->pubkey); + if (!status) { + status = tor_malloc_zero(sizeof(rtr_flags_t)); + digest256map_set(list->status_by_digest256, edkey->pubkey, status); + } + + *status |= add_status; + return 0; }
/** Add the fingerprint for this OR to the global list of recognized * identity key fingerprints. */ int -dirserv_add_own_fingerprint(crypto_pk_t *pk) +dirserv_add_own_fingerprint(crypto_pk_t *pk, const ed25519_public_key_t *edkey) { char fp[FINGERPRINT_LEN+1]; if (crypto_pk_get_fingerprint(pk, fp, 0)<0) { @@ -133,7 +164,14 @@ dirserv_add_own_fingerprint(crypto_pk_t *pk) } if (!fingerprint_list) fingerprint_list = authdir_config_new(); - add_fingerprint_to_dir(fp, fingerprint_list, 0); + if (add_rsa_fingerprint_to_dir(fp, fingerprint_list, 0) < 0) { + log_err(LD_BUG, "Error adding RSA fingerprint"); + return -1; + } + if (add_ed25519_to_dir(edkey, fingerprint_list, 0) < 0) { + log_err(LD_BUG, "Error adding ed25519 key"); + return -1; + } return 0; }
@@ -174,19 +212,11 @@ dirserv_load_fingerprint_file(void) fingerprint_list_new = authdir_config_new();
for (list=front; list; list=list->next) { - char digest_tmp[DIGEST_LEN]; rtr_flags_t add_status = 0; nickname = list->key; fingerprint = list->value; tor_strstrip(fingerprint, " "); /* remove spaces */ - if (strlen(fingerprint) != HEX_DIGEST_LEN || - base16_decode(digest_tmp, sizeof(digest_tmp), - fingerprint, HEX_DIGEST_LEN) != sizeof(digest_tmp)) { - log_notice(LD_CONFIG, - "Invalid fingerprint (nickname '%s', " - "fingerprint %s). Skipping.", - nickname, fingerprint); - continue; - } + + /* Determine what we should do with the relay with the nickname field. */ if (!strcasecmp(nickname, "!reject")) { add_status = RTR_REJECT; } else if (!strcasecmp(nickname, "!badexit")) { @@ -194,7 +224,34 @@ dirserv_load_fingerprint_file(void) } else if (!strcasecmp(nickname, "!invalid")) { add_status = RTR_INVALID; } - add_fingerprint_to_dir(fingerprint, fingerprint_list_new, add_status); + + /* Check if fingerprint is RSA or ed25519 by verifying it. */ + int ed25519_not_ok = -1, rsa_not_ok = -1; + + /* Attempt to add the RSA key. */ + if (strlen(fingerprint) == HEX_DIGEST_LEN) { + rsa_not_ok = add_rsa_fingerprint_to_dir(fingerprint, + fingerprint_list_new, + add_status); + } + + /* Check ed25519 key. We check the size to prevent buffer overflows. + * If valid, attempt to add it, */ + ed25519_public_key_t ed25519_pubkey_tmp; + if (strlen(fingerprint) == BASE64_DIGEST256_LEN) { + if (!digest256_from_base64((char *) ed25519_pubkey_tmp.pubkey, + fingerprint)) { + ed25519_not_ok = add_ed25519_to_dir(&ed25519_pubkey_tmp, + fingerprint_list_new, add_status); + } + } + + /* If both keys are invalid (or missing), log and skip. */ + if (ed25519_not_ok && rsa_not_ok) { + log_warn(LD_CONFIG, "Invalid fingerprint (nickname '%s', " + "fingerprint %s). Skipping.", nickname, fingerprint); + continue; + } }
config_free_lines(front); @@ -233,6 +290,8 @@ dirserv_router_get_status(const routerinfo_t *router, const char **msg, { char d[DIGEST_LEN]; const int key_pinning = get_options()->AuthDirPinKeys; + uint32_t r; + ed25519_public_key_t *signing_key = NULL;
if (crypto_pk_get_digest(router->identity_pkey, d)) { log_warn(LD_BUG,"Error computing fingerprint"); @@ -241,10 +300,15 @@ dirserv_router_get_status(const routerinfo_t *router, const char **msg, return RTR_REJECT; }
- /* Check for the more common reasons to reject a router first. */ - const uint32_t r = dirserv_get_status_impl(d, router->nickname, - router->addr, router->or_port, - router->platform, msg, severity); + /* First, check for the more common reasons to reject a router. */ + if (router->cache_info.signing_key_cert) { + /* This has an ed25519 identity key. */ + signing_key = &router->cache_info.signing_key_cert->signing_key; + } + r = dirserv_get_status_impl(d, signing_key, router->nickname, router->addr, + router->or_port, router->platform, msg, + severity); + if (r) return r;
@@ -304,13 +368,15 @@ dirserv_router_get_status(const routerinfo_t *router, const char **msg, /** Return true if there is no point in downloading the router described by * <b>rs</b> because this directory would reject it. */ int -dirserv_would_reject_router(const routerstatus_t *rs) +dirserv_would_reject_router(const routerstatus_t *rs, + const vote_routerstatus_t *vrs) { uint32_t res; + struct ed25519_public_key_t pk; + memcpy(&pk.pubkey, vrs->ed25519_id, ED25519_PUBKEY_LEN);
- res = dirserv_get_status_impl(rs->identity_digest, rs->nickname, - rs->addr, rs->or_port, - NULL, NULL, LOG_DEBUG); + res = dirserv_get_status_impl(rs->identity_digest, &pk, rs->nickname, + rs->addr, rs->or_port, NULL, NULL, LOG_DEBUG);
return (res & RTR_REJECT) != 0; } @@ -357,15 +423,16 @@ dirserv_rejects_tor_version(const char *platform, }
/** Helper: As dirserv_router_get_status, but takes the router fingerprint - * (hex, no spaces), nickname, address (used for logging only), IP address, OR - * port and platform (logging only) as arguments. + * (hex, no spaces), ed25519 key, nickname, address (used for logging only), + * IP address, OR port and platform (logging only) as arguments. * * Log messages at 'severity'. (There's not much point in * logging that we're rejecting servers we'll not download.) */ static uint32_t -dirserv_get_status_impl(const char *id_digest, const char *nickname, - uint32_t addr, uint16_t or_port, +dirserv_get_status_impl(const char *id_digest, + const ed25519_public_key_t *ed25519_public_key, + const char *nickname, uint32_t addr, uint16_t or_port, const char *platform, const char **msg, int severity) { uint32_t result = 0; @@ -398,16 +465,23 @@ dirserv_get_status_impl(const char *id_digest, const char *nickname, if (status_by_digest) result |= *status_by_digest;
+ if (ed25519_public_key) { + status_by_digest = digest256map_get(fingerprint_list->status_by_digest256, + ed25519_public_key->pubkey); + if (status_by_digest) + result |= *status_by_digest; + } + if (result & RTR_REJECT) { if (msg) - *msg = "Fingerprint is marked rejected -- if you think this is a " - "mistake please set a valid email address in ContactInfo and " - "send an email to bad-relays@lists.torproject.org mentioning " - "your fingerprint(s)?"; + *msg = "Fingerprint and/or ed25519 identity is marked rejected -- if " + "you think this is a mistake please set a valid email address " + "in ContactInfo and send an email to " + "bad-relays@lists.torproject.org mentioning your fingerprint(s)?"; return RTR_REJECT; } else if (result & RTR_INVALID) { if (msg) - *msg = "Fingerprint is marked invalid"; + *msg = "Fingerprint and/or ed25519 identity is marked invalid"; }
if (authdir_policy_badexit_address(addr, or_port)) { @@ -446,6 +520,7 @@ dirserv_free_fingerprint_list(void)
strmap_free(fingerprint_list->fp_by_name, tor_free_); digestmap_free(fingerprint_list->status_by_digest, tor_free_); + digest256map_free(fingerprint_list->status_by_digest256, tor_free_); tor_free(fingerprint_list); }
diff --git a/src/feature/dirauth/process_descs.h b/src/feature/dirauth/process_descs.h index e504daa7b..269a95044 100644 --- a/src/feature/dirauth/process_descs.h +++ b/src/feature/dirauth/process_descs.h @@ -15,6 +15,48 @@ // for was_router_added_t. #include "feature/nodelist/routerlist.h"
+#include "src/lib/crypt_ops/crypto_ed25519.h" + +struct authdir_config_t; + +/** Target of status_by_digest map. */ +typedef uint32_t rtr_flags_t; + +int add_rsa_fingerprint_to_dir(const char *fp, struct authdir_config_t *list, + rtr_flags_t add_status); + +int add_ed25519_to_dir(const ed25519_public_key_t *edkey, + struct authdir_config_t *list, + rtr_flags_t add_status); + +/** List of nickname->identity fingerprint mappings for all the routers + * that we name. Used to prevent router impersonation. */ +typedef struct authdir_config_t { + strmap_t *fp_by_name; /**< Map from lc nickname to fingerprint. */ + digestmap_t *status_by_digest; /**< Map from digest to router_status_t. */ + digest256map_t *status_by_digest256; /**< Map from digest256 to + * router_status_t. */ +} authdir_config_t; + +#if defined(PROCESS_DESCS_PRIVATE) || defined(TOR_UNIT_TESTS) + +/* 1 Historically used to indicate Named */ +#define RTR_INVALID 2 /**< Believed invalid. */ +#define RTR_REJECT 4 /**< We will not publish this router. */ +/* 8 Historically used to avoid using this as a dir. */ +#define RTR_BADEXIT 16 /**< We'll tell clients not to use this as an exit. */ +/* 32 Historically used to indicade Unnamed */ + +#endif /* defined(TOR_UNIT_TESTS) */ + +#ifdef TOR_UNIT_TESTS + +void authdir_init_fingerprint_list(void); + +authdir_config_t *authdir_return_fingerprint_list(void); + +#endif /* defined(PROCESS_DESCS_PRIVATE) || defined(TOR_UNIT_TESTS) */ + void dirserv_free_fingerprint_list(void);
#ifdef HAVE_MODULE_DIRAUTH @@ -28,11 +70,13 @@ enum was_router_added_t dirserv_add_descriptor(routerinfo_t *ri, const char **msg, const char *source);
-int dirserv_would_reject_router(const routerstatus_t *rs); +int dirserv_would_reject_router(const routerstatus_t *rs, + const vote_routerstatus_t *vrs); int authdir_wants_to_reject_router(routerinfo_t *ri, const char **msg, int complain, int *valid_out); -int dirserv_add_own_fingerprint(crypto_pk_t *pk); +int dirserv_add_own_fingerprint(crypto_pk_t *pk, + const ed25519_public_key_t *edkey); uint32_t dirserv_router_get_status(const routerinfo_t *router, const char **msg, int severity); @@ -68,9 +112,11 @@ dirserv_add_descriptor(routerinfo_t *ri, return (enum was_router_added_t)0; } static inline int -dirserv_would_reject_router(const routerstatus_t *rs) +dirserv_would_reject_router(const routerstatus_t *rs, + const vote_routerstatus_t *vrs) { (void)rs; + (void)vrs; return 0; } static inline int @@ -85,9 +131,10 @@ authdir_wants_to_reject_router(routerinfo_t *ri, const char **msg, return 0; } static inline int -dirserv_add_own_fingerprint(crypto_pk_t *pk) +dirserv_add_own_fingerprint(crypto_pk_t *pk, const ed25519_public_key_t *edkey) { (void)pk; + (void)edkey; return 0; } static inline uint32_t diff --git a/src/feature/nodelist/routerlist.c b/src/feature/nodelist/routerlist.c index 0709a3bbe..59d421da6 100644 --- a/src/feature/nodelist/routerlist.c +++ b/src/feature/nodelist/routerlist.c @@ -2558,8 +2558,15 @@ update_consensus_router_descriptor_downloads(time_t now, int is_vote, map = digestmap_new(); list_pending_descriptor_downloads(map, 0); SMARTLIST_FOREACH_BEGIN(consensus->routerstatus_list, void *, rsp) { - routerstatus_t *rs = - is_vote ? &(((vote_routerstatus_t *)rsp)->status) : rsp; + routerstatus_t *rs; + vote_routerstatus_t *vrs; + if (is_vote) { + rs = &(((vote_routerstatus_t *)rsp)->status); + vrs = rsp; + } else { + rs = rsp; + vrs = NULL; + } signed_descriptor_t *sd; if ((sd = router_get_by_descriptor_digest(rs->descriptor_digest))) { const routerinfo_t *ri; @@ -2584,7 +2591,7 @@ update_consensus_router_descriptor_downloads(time_t now, int is_vote, ++n_delayed; /* Not ready for retry. */ continue; } - if (authdir && dirserv_would_reject_router(rs)) { + if (authdir && is_vote && dirserv_would_reject_router(rs, vrs)) { ++n_would_reject; continue; /* We would throw it out immediately. */ } diff --git a/src/feature/relay/router.c b/src/feature/relay/router.c index 410ed8c2f..1915c020e 100644 --- a/src/feature/relay/router.c +++ b/src/feature/relay/router.c @@ -1074,8 +1074,10 @@ init_keys(void) if (authdir_mode_v3(options)) { const char *m = NULL; routerinfo_t *ri; - /* We need to add our own fingerprint so it gets recognized. */ - if (dirserv_add_own_fingerprint(get_server_identity_key())) { + /* We need to add our own fingerprint and ed25519 key so it gets + * recognized. */ + if (dirserv_add_own_fingerprint(get_server_identity_key(), + get_master_identity_key())) { log_err(LD_GENERAL,"Error adding own fingerprint to set of relays"); return -1; }