commit 6e4b10cf67d1ef39f8401b0bef3bc009584427c6 Author: Nick Mathewson nickm@torproject.org Date: Wed Feb 24 11:31:46 2021 -0500

Allow extra dirport URLs to be configured for authorities. --- src/app/config/config.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 92 insertions(+), 2 deletions(-)

diff --git a/src/app/config/config.c b/src/app/config/config.c index fa74907b3d..395da5e66a 100644 --- a/src/app/config/config.c +++ b/src/app/config/config.c @@ -5437,6 +5437,75 @@ pt_parse_transport_line(const or_options_t *options, return r; }

+/** + * Parse a flag describing an extra dirport for a directory authority. + * + * Right now, the supported format is exactly: + * `{upload,download,voting}=http://%5BIP:PORT%5D/%60. + * Other URL schemes, and other suffixes, might be supported in the future. + * + * Only call this function if `flag` starts with one of the above strings. + * + * Return 0 on success, and -1 on failure. + * + * If `ds` is provided, then add any parsed dirport to `ds`. If `ds` is NULL, + * take no action other than parsing. + **/ +static int +parse_dirauth_dirport(dir_server_t *ds, const char *flag) +{ + tor_assert(flag); + + auth_dirport_usage_t usage; + + if (!strcasecmpstart(flag, "upload=")) { + usage = AUTH_USAGE_UPLOAD; + } else if (!strcasecmpstart(flag, "download=")) { + usage = AUTH_USAGE_DOWNLOAD; + } else if (!strcasecmpstart(flag, "vote=")) { + usage = AUTH_USAGE_VOTING; + } else { + // We shouldn't get called with a flag that we don't recognize. + tor_assert_nonfatal_unreached(); + return -1; + } + + const char *eq = strchr(flag, '='); + tor_assert(eq); + const char *target = eq + 1; + + // Find the part inside the http://%7B....%7D/ + if (strcmpstart(target, "http://")) { + log_warn(LD_CONFIG, "Unsupported URL scheme in authority flag %s", flag); + return -1; + } + const char *addr = target + strlen("http://"); + + const char *eos = strchr(addr, '/'); + size_t addr_len; + if (eos && strcmp(eos, "/")) { + log_warn(LD_CONFIG, "Unsupported URL prefix in authority flag %s", flag); + return -1; + } else if (eos) { + addr_len = eos - addr; + } else { + addr_len = strlen(addr); + } + + // Finally, parse the addr:port part. + char *addr_string = tor_strndup(addr, addr_len); + tor_addr_port_t dirport; + memset(&dirport, 0, sizeof(dirport)); + int rv = tor_addr_port_parse(LOG_WARN, addr_string, + &dirport.addr, &dirport.port, -1); + if (ds != NULL && rv == 0) { + trusted_dir_server_add_dirport(ds, usage, &dirport); + } + + tor_free(addr_string); + return rv; +} + /** Read the contents of a DirAuthority line from <b>line</b>. If * <b>validate_only</b> is 0, and the line is well-formed, and it * shares any bits with <b>required_type</b> or <b>required_type</b> @@ -5457,6 +5526,7 @@ parse_dir_authority_line(const char *line, dirinfo_type_t required_type, char v3_digest[DIGEST_LEN]; dirinfo_type_t type = 0; double weight = 1.0; + smartlist_t *extra_dirports = smartlist_new();

memset(v3_digest, 0, sizeof(v3_digest));

@@ -5525,6 +5595,12 @@ parse_dir_authority_line(const char *line, dirinfo_type_t required_type, } ipv6_addrport_ptr = &ipv6_addrport; } + } else if (!strcasecmpstart(flag, "upload=") || + !strcasecmpstart(flag, "download=") || + !strcasecmpstart(flag, "vote=")) { + // We'll handle these after creating the authority object. + smartlist_add(extra_dirports, flag); + flag = NULL; // prevent double-free. } else { log_warn(LD_CONFIG, "Unrecognized flag '%s' on DirAuthority line", flag); @@ -5568,6 +5644,13 @@ parse_dir_authority_line(const char *line, dirinfo_type_t required_type, goto err; }

+ if (validate_only) { + SMARTLIST_FOREACH_BEGIN(extra_dirports, const char *, cp) { + if (parse_dirauth_dirport(NULL, cp) < 0) + goto err; + } SMARTLIST_FOREACH_END(cp); + } + if (!validate_only && (!required_type || required_type & type)) { dir_server_t *ds; if (required_type) @@ -5579,16 +5662,23 @@ parse_dir_authority_line(const char *line, dirinfo_type_t required_type, ipv6_addrport_ptr, digest, v3_digest, type, weight))) goto err; + + SMARTLIST_FOREACH_BEGIN(extra_dirports, const char *, cp) { + if (parse_dirauth_dirport(ds, cp) < 0) + goto err; + } SMARTLIST_FOREACH_END(cp); dir_server_add(ds); }

r = 0; goto done;

- err: + err: r = -1;

- done: + done: + SMARTLIST_FOREACH(extra_dirports, char*, s, tor_free(s)); + smartlist_free(extra_dirports); SMARTLIST_FOREACH(items, char*, s, tor_free(s)); smartlist_free(items); tor_free(addrport);