diff options
-rw-r--r-- | src/common/crypto.c | 23 | ||||
-rw-r--r-- | src/common/crypto.h | 4 | ||||
-rw-r--r-- | src/or/dirserv.c | 25 | ||||
-rw-r--r-- | src/or/dirvote.c | 68 | ||||
-rw-r--r-- | src/or/router.c | 25 | ||||
-rw-r--r-- | src/or/routerparse.c | 59 | ||||
-rw-r--r-- | src/or/routerparse.h | 3 |
7 files changed, 122 insertions, 85 deletions
diff --git a/src/common/crypto.c b/src/common/crypto.c index 22d57c7c8a..aeef1e3c6b 100644 --- a/src/common/crypto.c +++ b/src/common/crypto.c @@ -1631,6 +1631,29 @@ crypto_digest_assign(crypto_digest_t *into, memcpy(into,from,sizeof(crypto_digest_t)); } + +/** Given a list of strings in <b>lst</b>, set the <b>len_out</b>-byte digest + * at <b>digest_out</b> to the hash of the concatenation of those strings, + * plus the optional string <b>append</b>, computed with the algorithm + * <b>alg</b>. */ +void +crypto_digest_smartlist(char *digest_out, size_t len_out, + const smartlist_t *lst, const char *append, + digest_algorithm_t alg) +{ + crypto_digest_t *d; + if (alg == DIGEST_SHA1) + d = crypto_digest_new(); + else + d = crypto_digest256_new(alg); + SMARTLIST_FOREACH(lst, const char *, cp, + crypto_digest_add_bytes(d, cp, strlen(cp))); + if (append) + crypto_digest_add_bytes(d, append, strlen(append)); + crypto_digest_get_digest(d, digest_out, len_out); + crypto_digest_free(d); +} + /** Compute the HMAC-SHA-1 of the <b>msg_len</b> bytes in <b>msg</b>, using * the <b>key</b> of length <b>key_len</b>. Store the DIGEST_LEN-byte result * in <b>hmac_out</b>. diff --git a/src/common/crypto.h b/src/common/crypto.h index 12fcfae27e..e8f6eace1a 100644 --- a/src/common/crypto.h +++ b/src/common/crypto.h @@ -206,6 +206,10 @@ int crypto_digest(char *digest, const char *m, size_t len); int crypto_digest256(char *digest, const char *m, size_t len, digest_algorithm_t algorithm); int crypto_digest_all(digests_t *ds_out, const char *m, size_t len); +struct smartlist_t; +void crypto_digest_smartlist(char *digest_out, size_t len_out, + const struct smartlist_t *lst, const char *append, + digest_algorithm_t alg); const char *crypto_digest_algorithm_get_name(digest_algorithm_t alg); int crypto_digest_algorithm_parse_name(const char *name); crypto_digest_t *crypto_digest_new(void); diff --git a/src/or/dirserv.c b/src/or/dirserv.c index d5b90b936a..2bbfc9a7c6 100644 --- a/src/or/dirserv.c +++ b/src/or/dirserv.c @@ -2911,7 +2911,6 @@ generate_v2_networkstatus_opinion(void) size_t identity_pkey_len; char *status = NULL, *client_versions = NULL, *server_versions = NULL, *identity_pkey = NULL, *hostname = NULL; - size_t status_len; const or_options_t *options = get_options(); char fingerprint[FINGERPRINT_LEN+1]; char published[ISO_TIME_LEN+1]; @@ -3032,23 +3031,21 @@ generate_v2_networkstatus_opinion(void) smartlist_add_asprintf(chunks, "directory-signature %s\n", options->Nickname); - status = smartlist_join_strings(chunks, "", 0, NULL); -#define MAX_V2_OPINION_SIGNATURE_LEN 4096 - status_len = strlen(status) + MAX_V2_OPINION_SIGNATURE_LEN + 1; - status = tor_realloc(status, status_len); - - if (router_get_networkstatus_v2_hash(status, digest)<0) { - log_warn(LD_BUG, "Unable to hash network status"); - goto done; - } + crypto_digest_smartlist(digest, DIGEST_LEN, chunks, "", DIGEST_SHA1); note_crypto_pk_op(SIGN_DIR); - if (router_append_dirobj_signature(status, status_len,digest,DIGEST_LEN, - private_key)<0) { - log_warn(LD_BUG, "Unable to sign router status."); - goto done; + { + char *sig; + if (!(sig = router_get_dirobj_signature(digest,DIGEST_LEN, + private_key))) { + log_warn(LD_BUG, "Unable to sign router status."); + goto done; + } + smartlist_add(chunks, sig); } + status = smartlist_join_strings(chunks, "", 0, NULL); + { networkstatus_v2_t *ns; if (!(ns = networkstatus_v2_parse_from_string(status))) { diff --git a/src/or/dirvote.c b/src/or/dirvote.c index a7876701af..6ae4944369 100644 --- a/src/or/dirvote.c +++ b/src/or/dirvote.c @@ -75,7 +75,6 @@ format_networkstatus_vote(crypto_pk_t *private_signing_key, char *client_versions_line = NULL, *server_versions_line = NULL; networkstatus_voter_info_t *voter; char *status = NULL; - size_t status_len; tor_assert(private_signing_key); tor_assert(v3_ns->type == NS_TYPE_VOTE || v3_ns->type == NS_TYPE_OPINION); @@ -185,6 +184,11 @@ format_networkstatus_vote(crypto_pk_t *private_signing_key, smartlist_add(chunks, tor_strdup("directory-footer\n")); + /* The digest includes everything up through the space after + * directory-signature. (Yuck.) */ + crypto_digest_smartlist(digest, DIGEST_LEN, chunks, + "directory-signature ", DIGEST_SHA1); + { char signing_key_fingerprint[FINGERPRINT_LEN+1]; if (crypto_pk_get_fingerprint(private_signing_key, @@ -197,22 +201,19 @@ format_networkstatus_vote(crypto_pk_t *private_signing_key, signing_key_fingerprint); } - status = smartlist_join_strings(chunks, "", 0, NULL); -#define MAX_VOTE_SIGNATURE_LEN 4096 - status_len = strlen(status) + MAX_VOTE_SIGNATURE_LEN + 1; - status = tor_realloc(status, status_len); - - if (router_get_networkstatus_v3_hash(status, digest, DIGEST_SHA1)<0) - goto err; note_crypto_pk_op(SIGN_DIR); - if (router_append_dirobj_signature(status+strlen(status), - status_len, - digest, DIGEST_LEN, - private_signing_key)<0) { - log_warn(LD_BUG, "Unable to sign networkstatus vote."); - goto err; + { + char *sig = router_get_dirobj_signature(digest, DIGEST_LEN, + private_signing_key); + if (!sig) { + log_warn(LD_BUG, "Unable to sign networkstatus vote."); + goto err; + } + smartlist_add(chunks, sig); } + status = smartlist_join_strings(chunks, "", 0, NULL); + { networkstatus_t *v; if (!(v = networkstatus_parse_vote_from_string(status, NULL, @@ -479,24 +480,6 @@ compute_routerstatus_consensus(smartlist_t *votes, int consensus_method, return most; } -/** Given a list of strings in <b>lst</b>, set the <b>len_out</b>-byte digest - * at <b>digest_out</b> to the hash of the concatenation of those strings, - * computed with the algorithm <b>alg</b>. */ -static void -hash_list_members(char *digest_out, size_t len_out, - smartlist_t *lst, digest_algorithm_t alg) -{ - crypto_digest_t *d; - if (alg == DIGEST_SHA1) - d = crypto_digest_new(); - else - d = crypto_digest256_new(alg); - SMARTLIST_FOREACH(lst, const char *, cp, - crypto_digest_add_bytes(d, cp, strlen(cp))); - crypto_digest_get_digest(d, digest_out, len_out); - crypto_digest_free(d); -} - /** Sorting helper: compare two strings based on their values as base-ten * positive integers. (Non-integers are treated as prior to all integers, and * compared lexically.) */ @@ -2095,12 +2078,12 @@ networkstatus_compute_consensus(smartlist_t *votes, size_t digest_len = flavor == FLAV_NS ? DIGEST_LEN : DIGEST256_LEN; const char *algname = crypto_digest_algorithm_get_name(digest_alg); - char sigbuf[4096]; + char *signature; smartlist_add(chunks, tor_strdup("directory-signature ")); /* Compute the hash of the chunks. */ - hash_list_members(digest, digest_len, chunks, digest_alg); + crypto_digest_smartlist(digest, digest_len, chunks, "", digest_alg); /* Get the fingerprints */ crypto_pk_get_fingerprint(identity_key, fingerprint, 0); @@ -2116,14 +2099,12 @@ networkstatus_compute_consensus(smartlist_t *votes, signing_key_fingerprint); } /* And the signature. */ - sigbuf[0] = '\0'; - if (router_append_dirobj_signature(sigbuf, sizeof(sigbuf), - digest, digest_len, - signing_key)) { + if (!(signature = router_get_dirobj_signature(digest, digest_len, + signing_key))) { log_warn(LD_BUG, "Couldn't sign consensus networkstatus."); goto done; } - smartlist_add(chunks, tor_strdup(sigbuf)); + smartlist_add(chunks, signature); if (legacy_id_key_digest && legacy_signing_key && consensus_method >= 3) { smartlist_add(chunks, tor_strdup("directory-signature ")); @@ -2139,14 +2120,13 @@ networkstatus_compute_consensus(smartlist_t *votes, algname, fingerprint, signing_key_fingerprint); } - sigbuf[0] = '\0'; - if (router_append_dirobj_signature(sigbuf, sizeof(sigbuf), - digest, digest_len, - legacy_signing_key)) { + + if (!(signature = router_get_dirobj_signature(digest, digest_len, + legacy_signing_key))) { log_warn(LD_BUG, "Couldn't sign consensus networkstatus."); goto done; } - smartlist_add(chunks, tor_strdup(sigbuf)); + smartlist_add(chunks, signature); } } diff --git a/src/or/router.c b/src/or/router.c index 1b5909eb10..a391cddec3 100644 --- a/src/or/router.c +++ b/src/or/router.c @@ -2248,7 +2248,6 @@ router_dump_router_to_string(routerinfo_t *router, const or_options_t *options = get_options(); smartlist_t *chunks = NULL; char *output = NULL; - size_t output_len; /* Make sure the identity key matches the one in the routerinfo. */ if (!crypto_pk_eq_keys(ident_key, router->identity_pkey)) { @@ -2395,24 +2394,22 @@ router_dump_router_to_string(routerinfo_t *router, /* Sign the descriptor */ smartlist_add(chunks, tor_strdup("router-signature\n")); - output = smartlist_join_strings(chunks, "", 0, NULL); -#define MAX_DESC_SIGNATURE_LEN 4096 - output_len = strlen(output) + MAX_DESC_SIGNATURE_LEN + 1; - output = tor_realloc(output, output_len); - - if (router_get_router_hash(output, strlen(output), digest) < 0) { - goto err; - } + crypto_digest_smartlist(digest, DIGEST_LEN, chunks, "", DIGEST_SHA1); note_crypto_pk_op(SIGN_RTR); - if (router_append_dirobj_signature(output, output_len, - digest,DIGEST_LEN,ident_key)<0) { - log_warn(LD_BUG, "Couldn't sign router descriptor"); - goto err; + { + char *sig; + if (!(sig = router_get_dirobj_signature(digest, DIGEST_LEN, ident_key))) { + log_warn(LD_BUG, "Couldn't sign router descriptor"); + goto err; + } + smartlist_add(chunks, sig); } /* include a last '\n' */ - strlcat(output, "\n", output_len); + smartlist_add(chunks, tor_strdup("\n")); + + output = smartlist_join_strings(chunks, "", 0, NULL); #ifdef DEBUG_ROUTER_DUMP_ROUTER_TO_STRING { diff --git a/src/or/routerparse.c b/src/or/routerparse.c index ce2cd5c513..63f8fab104 100644 --- a/src/or/routerparse.c +++ b/src/or/routerparse.c @@ -683,20 +683,19 @@ router_get_extrainfo_hash(const char *s, size_t s_len, char *digest) "\nrouter-signature",'\n', DIGEST_SHA1); } -/** Helper: used to generate signatures for routers, directories and - * network-status objects. Given a digest in <b>digest</b> and a secret - * <b>private_key</b>, generate an PKCS1-padded signature, BASE64-encode it, - * surround it with -----BEGIN/END----- pairs, and write it to the - * <b>buf_len</b>-byte buffer at <b>buf</b>. Return 0 on success, -1 on - * failure. - */ -int -router_append_dirobj_signature(char *buf, size_t buf_len, const char *digest, - size_t digest_len, crypto_pk_t *private_key) +/** DOCDOC */ +char * +router_get_dirobj_signature(const char *digest, + size_t digest_len, + crypto_pk_t *private_key) { char *signature; size_t i, keysize; int siglen; + char *buf = NULL; + size_t buf_len; + /* overestimate of BEGIN/END lines total len. */ +#define BEGIN_END_OVERHEAD_LEN 64 keysize = crypto_pk_keysize(private_key); signature = tor_malloc(keysize); @@ -706,7 +705,12 @@ router_append_dirobj_signature(char *buf, size_t buf_len, const char *digest, log_warn(LD_BUG,"Couldn't sign digest."); goto err; } - if (strlcat(buf, "-----BEGIN SIGNATURE-----\n", buf_len) >= buf_len) + + /* The *2 here is a ridiculous overestimate of base-64 overhead. */ + buf_len = (siglen * 2) + BEGIN_END_OVERHEAD_LEN; + buf = tor_malloc(buf_len); + + if (strlcpy(buf, "-----BEGIN SIGNATURE-----\n", buf_len) >= buf_len) goto truncated; i = strlen(buf); @@ -719,13 +723,42 @@ router_append_dirobj_signature(char *buf, size_t buf_len, const char *digest, goto truncated; tor_free(signature); - return 0; + return buf; truncated: log_warn(LD_BUG,"tried to exceed string length."); err: tor_free(signature); - return -1; + tor_free(buf); + return NULL; +} + +/** Helper: used to generate signatures for routers, directories and + * network-status objects. Given a digest in <b>digest</b> and a secret + * <b>private_key</b>, generate an PKCS1-padded signature, BASE64-encode it, + * surround it with -----BEGIN/END----- pairs, and write it to the + * <b>buf_len</b>-byte buffer at <b>buf</b>. Return 0 on success, -1 on + * failure. + */ +int +router_append_dirobj_signature(char *buf, size_t buf_len, const char *digest, + size_t digest_len, crypto_pk_t *private_key) +{ + size_t sig_len, s_len; + char *sig = router_get_dirobj_signature(digest, digest_len, private_key); + if (!sig) { + log_warn(LD_BUG, "No signature generated"); + return -1; + } + sig_len = strlen(sig); + s_len = strlen(buf); + if (sig_len + s_len + 1 > buf_len) { + log_warn(LD_BUG, "Not enough room for signature"); + tor_free(sig); + return -1; + } + memcpy(buf+s_len, sig, sig_len+1); + return 0; } /** Return VS_RECOMMENDED if <b>myversion</b> is contained in diff --git a/src/or/routerparse.h b/src/or/routerparse.h index 859a691e2a..8eac3a2aa9 100644 --- a/src/or/routerparse.h +++ b/src/or/routerparse.h @@ -21,6 +21,9 @@ int router_get_networkstatus_v3_hash(const char *s, char *digest, int router_get_networkstatus_v3_hashes(const char *s, digests_t *digests); int router_get_extrainfo_hash(const char *s, size_t s_len, char *digest); #define DIROBJ_MAX_SIG_LEN 256 +char *router_get_dirobj_signature(const char *digest, + size_t digest_len, + crypto_pk_t *private_key); int router_append_dirobj_signature(char *buf, size_t buf_len, const char *digest, size_t digest_len, |