commit 3ca5fe81e33ab7848c848b683bffe12e743398f3
Author: Karsten Loesing <karsten.loesing(a)gmx.net>
Date: Wed Feb 26 10:44:55 2014 +0100
Write hashed bridge fingerprint to logs and to disk.
Implements #10884.
---
changes/bug10884 | 5 +++
doc/tor.1.txt | 4 +++
src/common/crypto.c | 22 ++++++++++++
src/common/crypto.h | 1 +
src/or/main.c | 2 ++
src/or/router.c | 100 ++++++++++++++++++++++++++++++++++-----------------
6 files changed, 101 insertions(+), 33 deletions(-)
diff --git a/changes/bug10884 b/changes/bug10884
new file mode 100644
index 0000000..815d893
--- /dev/null
+++ b/changes/bug10884
@@ -0,0 +1,5 @@
+ o Minor features:
+ - Bridges write the SHA1 digest of their identity key fingerprint to
+ notice-level logs and to hashed-fingerprint, so that bridge
+ operators can look up their bridge in Globe and similar tools.
+
diff --git a/doc/tor.1.txt b/doc/tor.1.txt
index f2960af..dc67889 100644
--- a/doc/tor.1.txt
+++ b/doc/tor.1.txt
@@ -2305,6 +2305,10 @@ __DataDirectory__**/keys/***::
__DataDirectory__**/fingerprint**::
Only used by servers. Holds the fingerprint of the server's identity key.
+__DataDirectory__**/hashed-fingerprint**::
+ Only used by bridges. Holds the hashed fingerprint of the bridge's
+ identity key. (That is, the hash of the hash of the identity key.)
+
__DataDirectory__**/approved-routers**::
Only for naming authoritative directory servers (see
**NamingAuthoritativeDirectory**). This file lists nickname to identity
diff --git a/src/common/crypto.c b/src/common/crypto.c
index 49dc55a..80d8351 100644
--- a/src/common/crypto.c
+++ b/src/common/crypto.c
@@ -1374,6 +1374,28 @@ crypto_pk_get_fingerprint(crypto_pk_t *pk, char *fp_out, int add_space)
return 0;
}
+/** Given a private or public key <b>pk</b>, put a hashed fingerprint of
+ * the public key into <b>fp_out</b> (must have at least FINGERPRINT_LEN+1
+ * bytes of space). Return 0 on success, -1 on failure.
+ *
+ * Hashed fingerprints are computed as the SHA1 digest of the SHA1 digest
+ * of the ASN.1 encoding of the public key, converted to hexadecimal, in
+ * upper case.
+ */
+int
+crypto_pk_get_hashed_fingerprint(crypto_pk_t *pk, char *fp_out)
+{
+ char digest[DIGEST_LEN], hashed_digest[DIGEST_LEN];
+ if (crypto_pk_get_digest(pk, digest)) {
+ return -1;
+ }
+ if (crypto_digest(hashed_digest, digest, DIGEST_LEN)) {
+ return -1;
+ }
+ base16_encode(fp_out, FINGERPRINT_LEN + 1, hashed_digest, DIGEST_LEN);
+ return 0;
+}
+
/* symmetric crypto */
/** Return a pointer to the key set for the cipher in <b>env</b>.
diff --git a/src/common/crypto.h b/src/common/crypto.h
index 3666d5f..4f0f1c1 100644
--- a/src/common/crypto.h
+++ b/src/common/crypto.h
@@ -182,6 +182,7 @@ crypto_pk_t *crypto_pk_asn1_decode(const char *str, size_t len);
int crypto_pk_get_digest(crypto_pk_t *pk, char *digest_out);
int crypto_pk_get_all_digests(crypto_pk_t *pk, digests_t *digests_out);
int crypto_pk_get_fingerprint(crypto_pk_t *pk, char *fp_out,int add_space);
+int crypto_pk_get_hashed_fingerprint(crypto_pk_t *pk, char *fp_out);
/* symmetric crypto */
const char *crypto_cipher_get_key(crypto_cipher_t *env);
diff --git a/src/or/main.c b/src/or/main.c
index 5404e96..b0529cd 100644
--- a/src/or/main.c
+++ b/src/or/main.c
@@ -2764,6 +2764,8 @@ sandbox_init_filter(void)
get_datadir_fname2("keys", "secret_id_key.tmp"), 1,
get_datadir_fname("fingerprint"), 1,
get_datadir_fname("fingerprint.tmp"), 1,
+ get_datadir_fname("hashed-fingerprint"), 1,
+ get_datadir_fname("hashed-fingerprint.tmp"), 1,
get_datadir_fname("cached-consensus"), 1,
get_datadir_fname("cached-consensus.tmp"), 1,
"/etc/resolv.conf", 0,
diff --git a/src/or/router.c b/src/or/router.c
index c22f4c3..b7d96ea 100644
--- a/src/or/router.c
+++ b/src/or/router.c
@@ -684,6 +684,68 @@ router_initialize_tls_context(void)
(unsigned int)lifetime);
}
+/** Compute fingerprint (or hashed fingerprint if hashed is 1) and write
+ * it to 'fingerprint' (or 'hashed-fingerprint'). Return 0 on success, or
+ * -1 if Tor should die,
+ */
+static int
+router_write_fingerprint(int hashed)
+{
+ char *keydir, *cp;
+ const char *fname = hashed ? "hashed-fingerprint" :
+ "fingerprint";
+ char fingerprint[FINGERPRINT_LEN+1];
+ const or_options_t *options = get_options();
+ /*nickname<space>fp\n\0 */
+ char fingerprint_line[MAX_NICKNAME_LEN+FINGERPRINT_LEN+3];
+ keydir = get_datadir_fname(fname);
+ log_info(LD_GENERAL,"Dumping %sfingerprint to \"%s\"...",
+ hashed ? "hashed " : "", keydir);
+ if (!hashed) {
+ if (crypto_pk_get_fingerprint(get_server_identity_key(),
+ fingerprint, 0) < 0) {
+ log_err(LD_GENERAL,"Error computing fingerprint");
+ tor_free(keydir);
+ return -1;
+ }
+ } else {
+ if (crypto_pk_get_hashed_fingerprint(get_server_identity_key(),
+ fingerprint) < 0) {
+ log_err(LD_GENERAL,"Error computing hashed fingerprint");
+ tor_free(keydir);
+ return -1;
+ }
+ }
+ tor_assert(strlen(options->Nickname) <= MAX_NICKNAME_LEN);
+ if (tor_snprintf(fingerprint_line, sizeof(fingerprint_line),
+ "%s %s\n",options->Nickname, fingerprint) < 0) {
+ log_err(LD_GENERAL,"Error writing %sfingerprint line",
+ hashed ? "hashed " : "");
+ tor_free(keydir);
+ return -1;
+ }
+ /* Check whether we need to write the (hashed-)fingerprint file. */
+ cp = NULL;
+ if (file_status(keydir) == FN_FILE)
+ cp = read_file_to_str(keydir, 0, NULL);
+ if (!cp || strcmp(cp, fingerprint_line)) {
+ if (write_str_to_file(keydir, fingerprint_line, 0)) {
+ log_err(LD_FS, "Error writing %sfingerprint line to file",
+ hashed ? "hashed " : "");
+ tor_free(keydir);
+ tor_free(cp);
+ return -1;
+ }
+ }
+ tor_free(cp);
+ tor_free(keydir);
+
+ log_notice(LD_GENERAL, "Your Tor %s identity key fingerprint is '%s %s'",
+ hashed ? "bridge's hashed" : "server's", options->Nickname,
+ fingerprint);
+ return 0;
+}
+
/** Initialize all OR private keys, and the TLS context, as necessary.
* On OPs, this only initializes the tls context. Return 0 on success,
* or -1 if Tor should die.
@@ -692,14 +754,10 @@ int
init_keys(void)
{
char *keydir;
- char fingerprint[FINGERPRINT_LEN+1];
- /*nickname<space>fp\n\0 */
- char fingerprint_line[MAX_NICKNAME_LEN+FINGERPRINT_LEN+3];
const char *mydesc;
crypto_pk_t *prkey;
char digest[DIGEST_LEN];
char v3_digest[DIGEST_LEN];
- char *cp;
const or_options_t *options = get_options();
dirinfo_type_t type;
time_t now = time(NULL);
@@ -889,40 +947,16 @@ init_keys(void)
}
}
- /* 5. Dump fingerprint to 'fingerprint' */
- keydir = get_datadir_fname("fingerprint");
- log_info(LD_GENERAL,"Dumping fingerprint to \"%s\"...",keydir);
- if (crypto_pk_get_fingerprint(get_server_identity_key(),
- fingerprint, 0) < 0) {
- log_err(LD_GENERAL,"Error computing fingerprint");
- tor_free(keydir);
+ /* 5. Dump fingerprint and possibly hashed fingerprint to files. */
+ if (router_write_fingerprint(0)) {
+ log_err(LD_FS, "Error writing fingerprint to file");
return -1;
}
- tor_assert(strlen(options->Nickname) <= MAX_NICKNAME_LEN);
- if (tor_snprintf(fingerprint_line, sizeof(fingerprint_line),
- "%s %s\n",options->Nickname, fingerprint) < 0) {
- log_err(LD_GENERAL,"Error writing fingerprint line");
- tor_free(keydir);
+ if (!public_server_mode(options) && router_write_fingerprint(1)) {
+ log_err(LD_FS, "Error writing hashed fingerprint to file");
return -1;
}
- /* Check whether we need to write the fingerprint file. */
- cp = NULL;
- if (file_status(keydir) == FN_FILE)
- cp = read_file_to_str(keydir, 0, NULL);
- if (!cp || strcmp(cp, fingerprint_line)) {
- if (write_str_to_file(keydir, fingerprint_line, 0)) {
- log_err(LD_FS, "Error writing fingerprint line to file");
- tor_free(keydir);
- tor_free(cp);
- return -1;
- }
- }
- tor_free(cp);
- tor_free(keydir);
- log_notice(LD_GENERAL,
- "Your Tor server's identity key fingerprint is '%s %s'",
- options->Nickname, fingerprint);
if (!authdir_mode(options))
return 0;
/* 6. [authdirserver only] load approved-routers file */