This is a relatively simple set of changes: we mostly need to
remove a few "but not for IPv6" changes.  We also needed to tweak
the handling of DNS code to generate RESOLVED cells that could get
an IPv6 answer in return.

Add 'flags' argument to begin cells, per proposal 208.

We'd like these functions to be circuit-relative so that we can
implement a per-circuit DNS cache and per-circuit DNS cache rules for
proposal 205 or its successors.  I'm doing this now, as a part of the
IPv6 exits code, since there are about to be a few more instances
of code using this.

Apparently some compilers like to eliminate memset() operations on
data that's about to go out-of-scope.  I've gone with the safest
possible replacement, which might be a bit slow.  I don't think this
is critical path in any way that will affect performance, but if it
is, we can work on that in 0.2.4.

Fixes bug 7352.

When we merged the channel code, we made the 'address' field of linked
directory connections created with begindir (and their associated edge
connections) contain an address:port string, when they should only
have contained the address part.

This patch also tweaks the interface to the get_descr method of
channels so that it takes a set of flags rather than a single flag.

In 4768c0ef (not in any released
version of Tor), we removed a little block of code that set the addr
field of an exit connection used in making a tunneled directory
request.  Turns out that wasn't right.

For everything we declare that starts with _, make it end with _ instead.

This is a machine-generated patch.  To make it, start by getting the
list of reserved identifiers using:

     git ls-tree -r --name-only HEAD | grep  '\.[ch]$' | \
       xargs ctags --c-kinds=defglmpstuvx -o - | grep '^_' | \
       cut -f 1 | sort| uniq

You might need gnu ctags.

Then pipe the output through this script:
==============================

use strict;

BEGIN { print "#!/usr/bin/perl -w -i -p\n\n"; }

chomp;

next if (
     /^__attribute__/ or
     /^__func__/ or
     /^_FILE_OFFSET_BITS/ or
     /^_FORTIFY_SOURCE/ or
     /^_GNU_SOURCE/ or
     /^_WIN32/ or
     /^_DARWIN_UNLIMITED/ or
     /^_FILE_OFFSET_BITS/ or
     /^_LARGEFILE64_SOURCE/ or
     /^_LFS64_LARGEFILE/ or
     /^__cdecl/ or
     /^__attribute__/ or
     /^__func__/ or
    /^_WIN32_WINNT/);

my $ident = $_;

my $better = $ident;
$better =~ s/^_//;

$better = "${better}_";

print "s/(?<![A-Za-z0-9_])$ident(?![A-Za-z0-9_])/$better/g;\n";
==============================

Then run the resulting script on all the files you want to change.
(That is, all the C except that in src/ext.)  The resulting script was:

==============================

s/(?<![A-Za-z0-9_])_address(?![A-Za-z0-9_])/address_/g;
s/(?<![A-Za-z0-9_])_aes_fill_buf(?![A-Za-z0-9_])/aes_fill_buf_/g;
s/(?<![A-Za-z0-9_])_AllowInvalid(?![A-Za-z0-9_])/AllowInvalid_/g;
s/(?<![A-Za-z0-9_])_AP_CONN_STATE_MAX(?![A-Za-z0-9_])/AP_CONN_STATE_MAX_/g;
s/(?<![A-Za-z0-9_])_AP_CONN_STATE_MIN(?![A-Za-z0-9_])/AP_CONN_STATE_MIN_/g;
s/(?<![A-Za-z0-9_])_assert_cache_ok(?![A-Za-z0-9_])/assert_cache_ok_/g;
s/(?<![A-Za-z0-9_])_A_UNKNOWN(?![A-Za-z0-9_])/A_UNKNOWN_/g;
s/(?<![A-Za-z0-9_])_base(?![A-Za-z0-9_])/base_/g;
s/(?<![A-Za-z0-9_])_BridgePassword_AuthDigest(?![A-Za-z0-9_])/BridgePassword_AuthDigest_/g;
s/(?<![A-Za-z0-9_])_buffer_stats_compare_entries(?![A-Za-z0-9_])/buffer_stats_compare_entries_/g;
s/(?<![A-Za-z0-9_])_chan_circid_entries_eq(?![A-Za-z0-9_])/chan_circid_entries_eq_/g;
s/(?<![A-Za-z0-9_])_chan_circid_entry_hash(?![A-Za-z0-9_])/chan_circid_entry_hash_/g;
s/(?<![A-Za-z0-9_])_check_no_tls_errors(?![A-Za-z0-9_])/check_no_tls_errors_/g;
s/(?<![A-Za-z0-9_])_c_hist_compare(?![A-Za-z0-9_])/c_hist_compare_/g;
s/(?<![A-Za-z0-9_])_circ(?![A-Za-z0-9_])/circ_/g;
s/(?<![A-Za-z0-9_])_circuit_get_global_list(?![A-Za-z0-9_])/circuit_get_global_list_/g;
s/(?<![A-Za-z0-9_])_circuit_mark_for_close(?![A-Za-z0-9_])/circuit_mark_for_close_/g;
s/(?<![A-Za-z0-9_])_CIRCUIT_PURPOSE_C_MAX(?![A-Za-z0-9_])/CIRCUIT_PURPOSE_C_MAX_/g;
s/(?<![A-Za-z0-9_])_CIRCUIT_PURPOSE_MAX(?![A-Za-z0-9_])/CIRCUIT_PURPOSE_MAX_/g;
s/(?<![A-Za-z0-9_])_CIRCUIT_PURPOSE_MIN(?![A-Za-z0-9_])/CIRCUIT_PURPOSE_MIN_/g;
s/(?<![A-Za-z0-9_])_CIRCUIT_PURPOSE_OR_MAX(?![A-Za-z0-9_])/CIRCUIT_PURPOSE_OR_MAX_/g;
s/(?<![A-Za-z0-9_])_CIRCUIT_PURPOSE_OR_MIN(?![A-Za-z0-9_])/CIRCUIT_PURPOSE_OR_MIN_/g;
s/(?<![A-Za-z0-9_])_cmp_int_strings(?![A-Za-z0-9_])/cmp_int_strings_/g;
s/(?<![A-Za-z0-9_])_compare_cached_resolves_by_expiry(?![A-Za-z0-9_])/compare_cached_resolves_by_expiry_/g;
s/(?<![A-Za-z0-9_])_compare_digests(?![A-Za-z0-9_])/compare_digests_/g;
s/(?<![A-Za-z0-9_])_compare_digests256(?![A-Za-z0-9_])/compare_digests256_/g;
s/(?<![A-Za-z0-9_])_compare_dir_src_ents_by_authority_id(?![A-Za-z0-9_])/compare_dir_src_ents_by_authority_id_/g;
s/(?<![A-Za-z0-9_])_compare_duration_idx(?![A-Za-z0-9_])/compare_duration_idx_/g;
s/(?<![A-Za-z0-9_])_compare_int(?![A-Za-z0-9_])/compare_int_/g;
s/(?<![A-Za-z0-9_])_compare_networkstatus_v2_published_on(?![A-Za-z0-9_])/compare_networkstatus_v2_published_on_/g;
s/(?<![A-Za-z0-9_])_compare_old_routers_by_identity(?![A-Za-z0-9_])/compare_old_routers_by_identity_/g;
s/(?<![A-Za-z0-9_])_compare_orports(?![A-Za-z0-9_])/compare_orports_/g;
s/(?<![A-Za-z0-9_])_compare_pairs(?![A-Za-z0-9_])/compare_pairs_/g;
s/(?<![A-Za-z0-9_])_compare_routerinfo_by_id_digest(?![A-Za-z0-9_])/compare_routerinfo_by_id_digest_/g;
s/(?<![A-Za-z0-9_])_compare_routerinfo_by_ip_and_bw(?![A-Za-z0-9_])/compare_routerinfo_by_ip_and_bw_/g;
s/(?<![A-Za-z0-9_])_compare_signed_descriptors_by_age(?![A-Za-z0-9_])/compare_signed_descriptors_by_age_/g;
s/(?<![A-Za-z0-9_])_compare_string_ptrs(?![A-Za-z0-9_])/compare_string_ptrs_/g;
s/(?<![A-Za-z0-9_])_compare_strings_for_pqueue(?![A-Za-z0-9_])/compare_strings_for_pqueue_/g;
s/(?<![A-Za-z0-9_])_compare_strs(?![A-Za-z0-9_])/compare_strs_/g;
s/(?<![A-Za-z0-9_])_compare_tor_version_str_ptr(?![A-Za-z0-9_])/compare_tor_version_str_ptr_/g;
s/(?<![A-Za-z0-9_])_compare_vote_rs(?![A-Za-z0-9_])/compare_vote_rs_/g;
s/(?<![A-Za-z0-9_])_compare_votes_by_authority_id(?![A-Za-z0-9_])/compare_votes_by_authority_id_/g;
s/(?<![A-Za-z0-9_])_compare_without_first_ch(?![A-Za-z0-9_])/compare_without_first_ch_/g;
s/(?<![A-Za-z0-9_])_connection_free(?![A-Za-z0-9_])/connection_free_/g;
s/(?<![A-Za-z0-9_])_connection_mark_and_flush(?![A-Za-z0-9_])/connection_mark_and_flush_/g;
s/(?<![A-Za-z0-9_])_connection_mark_for_close(?![A-Za-z0-9_])/connection_mark_for_close_/g;
s/(?<![A-Za-z0-9_])_connection_mark_unattached_ap(?![A-Za-z0-9_])/connection_mark_unattached_ap_/g;
s/(?<![A-Za-z0-9_])_connection_write_to_buf_impl(?![A-Za-z0-9_])/connection_write_to_buf_impl_/g;
s/(?<![A-Za-z0-9_])_ConnLimit(?![A-Za-z0-9_])/ConnLimit_/g;
s/(?<![A-Za-z0-9_])_CONN_TYPE_MAX(?![A-Za-z0-9_])/CONN_TYPE_MAX_/g;
s/(?<![A-Za-z0-9_])_CONN_TYPE_MIN(?![A-Za-z0-9_])/CONN_TYPE_MIN_/g;
s/(?<![A-Za-z0-9_])_CONTROL_CONN_STATE_MAX(?![A-Za-z0-9_])/CONTROL_CONN_STATE_MAX_/g;
s/(?<![A-Za-z0-9_])_CONTROL_CONN_STATE_MIN(?![A-Za-z0-9_])/CONTROL_CONN_STATE_MIN_/g;
s/(?<![A-Za-z0-9_])_CPUWORKER_STATE_MAX(?![A-Za-z0-9_])/CPUWORKER_STATE_MAX_/g;
s/(?<![A-Za-z0-9_])_CPUWORKER_STATE_MIN(?![A-Za-z0-9_])/CPUWORKER_STATE_MIN_/g;
s/(?<![A-Za-z0-9_])_crypto_dh_get_dh(?![A-Za-z0-9_])/crypto_dh_get_dh_/g;
s/(?<![A-Za-z0-9_])_crypto_global_initialized(?![A-Za-z0-9_])/crypto_global_initialized_/g;
s/(?<![A-Za-z0-9_])_crypto_new_pk_from_rsa(?![A-Za-z0-9_])/crypto_new_pk_from_rsa_/g;
s/(?<![A-Za-z0-9_])_crypto_pk_get_evp_pkey(?![A-Za-z0-9_])/crypto_pk_get_evp_pkey_/g;
s/(?<![A-Za-z0-9_])_crypto_pk_get_rsa(?![A-Za-z0-9_])/crypto_pk_get_rsa_/g;
s/(?<![A-Za-z0-9_])_DIR_CONN_STATE_MAX(?![A-Za-z0-9_])/DIR_CONN_STATE_MAX_/g;
s/(?<![A-Za-z0-9_])_DIR_CONN_STATE_MIN(?![A-Za-z0-9_])/DIR_CONN_STATE_MIN_/g;
s/(?<![A-Za-z0-9_])_DIR_PURPOSE_MAX(?![A-Za-z0-9_])/DIR_PURPOSE_MAX_/g;
s/(?<![A-Za-z0-9_])_DIR_PURPOSE_MIN(?![A-Za-z0-9_])/DIR_PURPOSE_MIN_/g;
s/(?<![A-Za-z0-9_])_dirreq_map_get(?![A-Za-z0-9_])/dirreq_map_get_/g;
s/(?<![A-Za-z0-9_])_dirreq_map_put(?![A-Za-z0-9_])/dirreq_map_put_/g;
s/(?<![A-Za-z0-9_])_dns_randfn(?![A-Za-z0-9_])/dns_randfn_/g;
s/(?<![A-Za-z0-9_])_dummy(?![A-Za-z0-9_])/dummy_/g;
s/(?<![A-Za-z0-9_])_edge(?![A-Za-z0-9_])/edge_/g;
s/(?<![A-Za-z0-9_])_END_CIRC_REASON_MAX(?![A-Za-z0-9_])/END_CIRC_REASON_MAX_/g;
s/(?<![A-Za-z0-9_])_END_CIRC_REASON_MIN(?![A-Za-z0-9_])/END_CIRC_REASON_MIN_/g;
s/(?<![A-Za-z0-9_])_EOF(?![A-Za-z0-9_])/EOF_/g;
s/(?<![A-Za-z0-9_])_ERR(?![A-Za-z0-9_])/ERR_/g;
s/(?<![A-Za-z0-9_])_escaped_val(?![A-Za-z0-9_])/escaped_val_/g;
s/(?<![A-Za-z0-9_])_evdns_log(?![A-Za-z0-9_])/evdns_log_/g;
s/(?<![A-Za-z0-9_])_evdns_nameserver_add_impl(?![A-Za-z0-9_])/evdns_nameserver_add_impl_/g;
s/(?<![A-Za-z0-9_])_EVENT_MAX(?![A-Za-z0-9_])/EVENT_MAX_/g;
s/(?<![A-Za-z0-9_])_EVENT_MIN(?![A-Za-z0-9_])/EVENT_MIN_/g;
s/(?<![A-Za-z0-9_])_ExcludeExitNodesUnion(?![A-Za-z0-9_])/ExcludeExitNodesUnion_/g;
s/(?<![A-Za-z0-9_])_EXIT_CONN_STATE_MAX(?![A-Za-z0-9_])/EXIT_CONN_STATE_MAX_/g;
s/(?<![A-Za-z0-9_])_EXIT_CONN_STATE_MIN(?![A-Za-z0-9_])/EXIT_CONN_STATE_MIN_/g;
s/(?<![A-Za-z0-9_])_EXIT_PURPOSE_MAX(?![A-Za-z0-9_])/EXIT_PURPOSE_MAX_/g;
s/(?<![A-Za-z0-9_])_EXIT_PURPOSE_MIN(?![A-Za-z0-9_])/EXIT_PURPOSE_MIN_/g;
s/(?<![A-Za-z0-9_])_extrainfo_free(?![A-Za-z0-9_])/extrainfo_free_/g;
s/(?<![A-Za-z0-9_])_find_by_keyword(?![A-Za-z0-9_])/find_by_keyword_/g;
s/(?<![A-Za-z0-9_])_free_cached_dir(?![A-Za-z0-9_])/free_cached_dir_/g;
s/(?<![A-Za-z0-9_])_free_cached_resolve(?![A-Za-z0-9_])/free_cached_resolve_/g;
s/(?<![A-Za-z0-9_])_free_duplicate_routerstatus_entry(?![A-Za-z0-9_])/free_duplicate_routerstatus_entry_/g;
s/(?<![A-Za-z0-9_])_free_link_history(?![A-Za-z0-9_])/free_link_history_/g;
s/(?<![A-Za-z0-9_])_geoip_compare_entries(?![A-Za-z0-9_])/geoip_compare_entries_/g;
s/(?<![A-Za-z0-9_])_geoip_compare_key_to_entry(?![A-Za-z0-9_])/geoip_compare_key_to_entry_/g;
s/(?<![A-Za-z0-9_])_hex_decode_digit(?![A-Za-z0-9_])/hex_decode_digit_/g;
s/(?<![A-Za-z0-9_])_idxplus1(?![A-Za-z0-9_])/idxplus1_/g;
s/(?<![A-Za-z0-9_])__libc_enable_secure(?![A-Za-z0-9_])/_libc_enable_secure_/g;
s/(?<![A-Za-z0-9_])_log_debug(?![A-Za-z0-9_])/log_debug_/g;
s/(?<![A-Za-z0-9_])_log_err(?![A-Za-z0-9_])/log_err_/g;
s/(?<![A-Za-z0-9_])_log_fn(?![A-Za-z0-9_])/log_fn_/g;
s/(?<![A-Za-z0-9_])_log_fn_function_name(?![A-Za-z0-9_])/log_fn_function_name_/g;
s/(?<![A-Za-z0-9_])_log_global_min_severity(?![A-Za-z0-9_])/log_global_min_severity_/g;
s/(?<![A-Za-z0-9_])_log_info(?![A-Za-z0-9_])/log_info_/g;
s/(?<![A-Za-z0-9_])_log_notice(?![A-Za-z0-9_])/log_notice_/g;
s/(?<![A-Za-z0-9_])_log_prefix(?![A-Za-z0-9_])/log_prefix_/g;
s/(?<![A-Za-z0-9_])_log_warn(?![A-Za-z0-9_])/log_warn_/g;
s/(?<![A-Za-z0-9_])_magic(?![A-Za-z0-9_])/magic_/g;
s/(?<![A-Za-z0-9_])_MALLOC_LOCK(?![A-Za-z0-9_])/MALLOC_LOCK_/g;
s/(?<![A-Za-z0-9_])_MALLOC_LOCK_INIT(?![A-Za-z0-9_])/MALLOC_LOCK_INIT_/g;
s/(?<![A-Za-z0-9_])_MALLOC_UNLOCK(?![A-Za-z0-9_])/MALLOC_UNLOCK_/g;
s/(?<![A-Za-z0-9_])_microdesc_eq(?![A-Za-z0-9_])/microdesc_eq_/g;
s/(?<![A-Za-z0-9_])_microdesc_hash(?![A-Za-z0-9_])/microdesc_hash_/g;
s/(?<![A-Za-z0-9_])_MIN_TOR_TLS_ERROR_VAL(?![A-Za-z0-9_])/MIN_TOR_TLS_ERROR_VAL_/g;
s/(?<![A-Za-z0-9_])_mm_free(?![A-Za-z0-9_])/mm_free_/g;
s/(?<![A-Za-z0-9_])_NIL(?![A-Za-z0-9_])/NIL_/g;
s/(?<![A-Za-z0-9_])_n_openssl_mutexes(?![A-Za-z0-9_])/n_openssl_mutexes_/g;
s/(?<![A-Za-z0-9_])_openssl_dynlock_create_cb(?![A-Za-z0-9_])/openssl_dynlock_create_cb_/g;
s/(?<![A-Za-z0-9_])_openssl_dynlock_destroy_cb(?![A-Za-z0-9_])/openssl_dynlock_destroy_cb_/g;
s/(?<![A-Za-z0-9_])_openssl_dynlock_lock_cb(?![A-Za-z0-9_])/openssl_dynlock_lock_cb_/g;
s/(?<![A-Za-z0-9_])_openssl_locking_cb(?![A-Za-z0-9_])/openssl_locking_cb_/g;
s/(?<![A-Za-z0-9_])_openssl_mutexes(?![A-Za-z0-9_])/openssl_mutexes_/g;
s/(?<![A-Za-z0-9_])_option_abbrevs(?![A-Za-z0-9_])/option_abbrevs_/g;
s/(?<![A-Za-z0-9_])_option_vars(?![A-Za-z0-9_])/option_vars_/g;
s/(?<![A-Za-z0-9_])_OR_CONN_STATE_MAX(?![A-Za-z0-9_])/OR_CONN_STATE_MAX_/g;
s/(?<![A-Za-z0-9_])_OR_CONN_STATE_MIN(?![A-Za-z0-9_])/OR_CONN_STATE_MIN_/g;
s/(?<![A-Za-z0-9_])_OutboundBindAddressIPv4(?![A-Za-z0-9_])/OutboundBindAddressIPv4_/g;
s/(?<![A-Za-z0-9_])_OutboundBindAddressIPv6(?![A-Za-z0-9_])/OutboundBindAddressIPv6_/g;
s/(?<![A-Za-z0-9_])_PDS_PREFER_TUNNELED_DIR_CONNS(?![A-Za-z0-9_])/PDS_PREFER_TUNNELED_DIR_CONNS_/g;
s/(?<![A-Za-z0-9_])_port(?![A-Za-z0-9_])/port_/g;
s/(?<![A-Za-z0-9_])__progname(?![A-Za-z0-9_])/_progname_/g;
s/(?<![A-Za-z0-9_])_PublishServerDescriptor(?![A-Za-z0-9_])/PublishServerDescriptor_/g;
s/(?<![A-Za-z0-9_])_remove_old_client_helper(?![A-Za-z0-9_])/remove_old_client_helper_/g;
s/(?<![A-Za-z0-9_])_rend_cache_entry_free(?![A-Za-z0-9_])/rend_cache_entry_free_/g;
s/(?<![A-Za-z0-9_])_routerlist_find_elt(?![A-Za-z0-9_])/routerlist_find_elt_/g;
s/(?<![A-Za-z0-9_])_SafeLogging(?![A-Za-z0-9_])/SafeLogging_/g;
s/(?<![A-Za-z0-9_])_SHORT_FILE_(?![A-Za-z0-9_])/SHORT_FILE__/g;
s/(?<![A-Za-z0-9_])_state_abbrevs(?![A-Za-z0-9_])/state_abbrevs_/g;
s/(?<![A-Za-z0-9_])_state_vars(?![A-Za-z0-9_])/state_vars_/g;
s/(?<![A-Za-z0-9_])_t(?![A-Za-z0-9_])/t_/g;
s/(?<![A-Za-z0-9_])_t32(?![A-Za-z0-9_])/t32_/g;
s/(?<![A-Za-z0-9_])_test_op_ip6(?![A-Za-z0-9_])/test_op_ip6_/g;
s/(?<![A-Za-z0-9_])_thread1_name(?![A-Za-z0-9_])/thread1_name_/g;
s/(?<![A-Za-z0-9_])_thread2_name(?![A-Za-z0-9_])/thread2_name_/g;
s/(?<![A-Za-z0-9_])_thread_test_func(?![A-Za-z0-9_])/thread_test_func_/g;
s/(?<![A-Za-z0-9_])_thread_test_mutex(?![A-Za-z0-9_])/thread_test_mutex_/g;
s/(?<![A-Za-z0-9_])_thread_test_start1(?![A-Za-z0-9_])/thread_test_start1_/g;
s/(?<![A-Za-z0-9_])_thread_test_start2(?![A-Za-z0-9_])/thread_test_start2_/g;
s/(?<![A-Za-z0-9_])_thread_test_strmap(?![A-Za-z0-9_])/thread_test_strmap_/g;
s/(?<![A-Za-z0-9_])_tor_calloc(?![A-Za-z0-9_])/tor_calloc_/g;
s/(?<![A-Za-z0-9_])_TOR_CHANNEL_INTERNAL(?![A-Za-z0-9_])/TOR_CHANNEL_INTERNAL_/g;
s/(?<![A-Za-z0-9_])_TOR_CIRCUITMUX_EWMA_C(?![A-Za-z0-9_])/TOR_CIRCUITMUX_EWMA_C_/g;
s/(?<![A-Za-z0-9_])_tor_free(?![A-Za-z0-9_])/tor_free_/g;
s/(?<![A-Za-z0-9_])_tor_malloc(?![A-Za-z0-9_])/tor_malloc_/g;
s/(?<![A-Za-z0-9_])_tor_malloc_zero(?![A-Za-z0-9_])/tor_malloc_zero_/g;
s/(?<![A-Za-z0-9_])_tor_memdup(?![A-Za-z0-9_])/tor_memdup_/g;
s/(?<![A-Za-z0-9_])_tor_realloc(?![A-Za-z0-9_])/tor_realloc_/g;
s/(?<![A-Za-z0-9_])_tor_strdup(?![A-Za-z0-9_])/tor_strdup_/g;
s/(?<![A-Za-z0-9_])_tor_strndup(?![A-Za-z0-9_])/tor_strndup_/g;
s/(?<![A-Za-z0-9_])_TOR_TLS_SYSCALL(?![A-Za-z0-9_])/TOR_TLS_SYSCALL_/g;
s/(?<![A-Za-z0-9_])_TOR_TLS_ZERORETURN(?![A-Za-z0-9_])/TOR_TLS_ZERORETURN_/g;
s/(?<![A-Za-z0-9_])__USE_ISOC99(?![A-Za-z0-9_])/_USE_ISOC99_/g;
s/(?<![A-Za-z0-9_])_UsingTestNetworkDefaults(?![A-Za-z0-9_])/UsingTestNetworkDefaults_/g;
s/(?<![A-Za-z0-9_])_val(?![A-Za-z0-9_])/val_/g;
s/(?<![A-Za-z0-9_])_void_for_alignment(?![A-Za-z0-9_])/void_for_alignment_/g;

==============================

The SMARTLIST_FOREACH macro is more convenient than BEGIN/END when
you have a nice short loop body, but using it for long bodies makes
your preprocessor tell the compiler that all the code is on the same
line.  That causes grief, since compiler warnings and debugger lines
will all refer to that one line.

So, here's a new style rule: SMARTLIST_FOREACH blocks need to be
short.

The code that detected the source of a remapped address checked that
an address mapping's source was a given rewrite rule if addr_orig had
no .exit, and addr did have a .exit after processing that rule.  But
addr_orig was formatted for logging: it was not the original address
at all, but rather was the address escaped for logging and possibly
replaced with "[scrubbed]".

This new logic will correctly set ADDRMAPSRC_NONE in the case when the
address starts life as a .exit address, so that AllowDotExit can work
again.

Fixes bug 6211; bugfix on 0.2.3.17-beta

Also, try to resolve some doxygen issues.  First, define a magic
"This is doxygen!" macro so that we take the correct branch in
various #if/#else/#endifs in order to get the right documentation.
Second, add in a few grouping @{ and @} entries in order to get some
variables and fields to get grouped together.

Fabian Keil authored Sep 25, 2011 and Nick Mathewson committed May 16, 2012

In connection_ap_handshake_process_socks(), mark the socks request as finished if a reply is send after a parse error

Silences the log message:
[warn] {BUG} _connection_mark_unattached_ap(): Bug: stream (marked at connection_edge.c:2224) sending two socks replies?
after the client triggered the "Tor is not an HTTP Proxy" response.

No additional socks reply was sent, though.

This time, I follow grarpamp's suggestion and move the check for
.exit+AllowDotExit 0 to the top of connection_ap_rewrite_and_attach,
before any rewriting occurs.  This way, .exit addresses are
forbidden as they arrive from a socks connection or a DNSPort
request, and not otherwise.

It _is_ a little more complicated than that, though.  We need to
treat any .exit addresses whose source is TrackHostExits as meaning
that we can retry without that exit.  We also need to treat any
.exit address that comes from an AutomapHostsOnResolve operation as
user-provided (and thus forbidden if AllowDotExits==0), so that
transitioning from AllowDotExits==1 to AllowDotExits==0 will
actually turn off automapped .exit addresses.

Nick Mathewson authored May 01, 2012 and Roger Dingledine committed May 01, 2012

Fix for bug 5723; bugfix on 0.2.3.1-alpha (commit 22f723e4)

fixes bug 5623.

Sending them on is futile, since we will be told "127.0.0.1" and then
think we've been lied to.  Partial fix for 2822.

Partial fix for ticket 2822.

These were found by looking for tor_snprintf() instances that were
preceeded closely by tor_malloc(), though I probably converted some
more snprintfs as well.

(In every case, make sure that the length variable (if any) is
removed, renamed, or lowered, so that anything else that might have
assumed a longer buffer doesn't exist.)

These were found by looking for tor_snprintf() instances that were
followed closely by tor_strdup(), though I probably converted some
other snprintfs as well.

This fixes bug 3325, where a bad .exit would get logged as a bad .onion

Robert Ransom authored May 31, 2011 and Nick Mathewson committed Nov 30, 2011

The client's anonymity when accessing a non-HS address in tor2web-mode
would be easily nuked by inserting an inline image with a .onion URL, so
don't even pretend to access non-HS addresses through Tor.

This resolves a loop warning on "MapAddress *.example.com
example.com", makes the rewrite log messages correct, and fixes the
behavior of "MapAddress *.a *.b" when just given "a" as an input.

MapAddress *.torproject.org torproject.org would have been interpreted
as a map from a domain to itself, and would have cleared the mapping.
Now we require not only a match of domains, but of wildcards.

In this new representation for wildcarded addresses, there are no
longer any 'magic addresses': rather, "a.b c.d", "*.a.b c.d" and
"*.a.b *.c.d" are all represented by a mapping from "a.b" to "c.d". we
now distinguish them by setting bits in the addressmap_entry_t
structure, where src_wildcard is set if the source address had a
wildcard, and dst_wildcard is set if the target address had a
wildcard.

This lets the case where "*.a.b *.c.d" or "*.a.b c.d" remap the
address "a.b" get handled trivially, and lets us simplify and improve
the addressmap_match_superdomains implementation: we can now have it
run in O(parts of address) rather than O(entries in addressmap).

Robert Hogan authored Dec 27, 2010 and Nick Mathewson committed Nov 30, 2011

    1. Only allow '*.' in MapAddress expressions. Ignore '*ample.com' and '.example.com'.
       This has resulted in a slight refactoring of config_register_addressmaps.
    2. Add some more detail to the man page entry for AddressMap.
    3. Fix initialization of a pointer to NULL rather than 0.
    4. Update the unit tests to cater for the changes in 1 and test more explicitly for
       recursive mapping.

Robert Hogan authored Dec 13, 2010 and Nick Mathewson committed Nov 30, 2011

1. Implement the following mapping rules:

   MapAddress a.b.c d.e.f # This is what we have now
   MapAddress .a.b.c d.e.f # Replaces any address ending with .a.b.c with d.e.f
   MapAddress .a.b.c .d.e.f # Replaces the .a.b.c at the end of any addr with .d.e.f

   (Note that 'a.b.c .d.e.f' is invalid, and will be rejected.)

2. Add tests for the new rules.

3. Allow proper wildcard annotation, i.e. '*.d.e' '.d.e' will still work.

4. Update addressmap_entry_t with an is_wildcard member.