March 2013 - tor-commits - lists.torproject.org

[tor/master] Use fds, not stdio, to manage microdescriptor files
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit d54ccbe9fd5c9ca6ff53ad7d0efc4d0e837062ab Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Mar 11 14:37:44 2013 -0400 Use fds, not stdio, to manage microdescriptor files This is part of an attempt to mitigate 8031. --- src/or/microdesc.c | 40 ++++++++++++++++++++-------------------- 1 files changed, 20 insertions(+), 20 deletions(-) diff --git a/src/or/microdesc.c b/src/or/microdesc.c index b4d22c1..0a9724f 100644 --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@ -70,7 +70,7 @@ HT_GENERATE(microdesc_map, microdesc_t, node, * *annotation_len_out to the number of bytes written as * annotations. */ static ssize_t -dump_microdescriptor(FILE *f, microdesc_t *md, size_t *annotation_len_out) +dump_microdescriptor(int fd, microdesc_t *md, size_t *annotation_len_out) { ssize_t r = 0; size_t written; @@ -80,10 +80,10 @@ dump_microdescriptor(FILE *f, microdesc_t *md, size_t *annotation_len_out) char annotation[ISO_TIME_LEN+32]; format_iso_time(buf, md->last_listed); tor_snprintf(annotation, sizeof(annotation), "@last-listed %s\n", buf); - if (fputs(annotation, f) < 0) { + if (write_all(fd, annotation, strlen(annotation), 0) < 0) { log_warn(LD_DIR, "Couldn't write microdescriptor annotation: %s", - strerror(ferror(f))); + strerror(errno)); return -1; } r += strlen(annotation); @@ -92,13 +92,13 @@ dump_microdescriptor(FILE *f, microdesc_t *md, size_t *annotation_len_out) *annotation_len_out = 0; } - md->off = (off_t) ftell(f); - written = fwrite(md->body, 1, md->bodylen, f); + md->off = tor_fd_getpos(fd); + written = write_all(fd, md->body, md->bodylen, 0); if (written != md->bodylen) { log_warn(LD_DIR, "Couldn't dump microdescriptor (wrote %lu out of %lu): %s", (unsigned long)written, (unsigned long)md->bodylen, - strerror(ferror(f))); + strerror(errno)); return -1; } r += md->bodylen; @@ -197,15 +197,15 @@ microdescs_add_list_to_cache(microdesc_cache_t *cache, { smartlist_t *added; open_file_t *open_file = NULL; - FILE *f = NULL; + int fd = -1; // int n_added = 0; ssize_t size = 0; if (where == SAVED_NOWHERE && !no_save) { - f = start_writing_to_stdio_file(cache->journal_fname, - OPEN_FLAGS_APPEND|O_BINARY, - 0600, &open_file); - if (!f) { + fd = start_writing_to_file(cache->journal_fname, + OPEN_FLAGS_APPEND|O_BINARY, + 0600, &open_file); + if (fd < 0) { log_warn(LD_DIR, "Couldn't append to journal in %s: %s", cache->journal_fname, strerror(errno)); return NULL; @@ -227,9 +227,9 @@ microdescs_add_list_to_cache(microdesc_cache_t *cache, } /* Okay, it's a new one. */ - if (f) { + if (fd >= 0) { size_t annotation_len; - size = dump_microdescriptor(f, md, &annotation_len); + size = dump_microdescriptor(fd, md, &annotation_len); if (size < 0) { /* we already warned in dump_microdescriptor; */ abort_writing_to_file(open_file); @@ -251,7 +251,7 @@ microdescs_add_list_to_cache(microdesc_cache_t *cache, cache->total_len_seen += md->bodylen; } SMARTLIST_FOREACH_END(md); - if (f) + if (fd >= 0) finish_writing_to_file(open_file); /*XXX Check me.*/ { @@ -405,7 +405,7 @@ int microdesc_cache_rebuild(microdesc_cache_t *cache, int force) { open_file_t *open_file; - FILE *f; + int fd = -1; microdesc_t **mdp; smartlist_t *wrote; ssize_t size; @@ -429,10 +429,10 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) orig_size = (int)(cache->cache_content ? cache->cache_content->size : 0); orig_size += (int)cache->journal_len; - f = start_writing_to_stdio_file(cache->cache_fname, - OPEN_FLAGS_REPLACE|O_BINARY, - 0600, &open_file); - if (!f) + fd = start_writing_to_file(cache->cache_fname, + OPEN_FLAGS_REPLACE|O_BINARY, + 0600, &open_file); + if (fd < 0) return -1; wrote = smartlist_new(); @@ -443,7 +443,7 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) if (md->no_save) continue; - size = dump_microdescriptor(f, md, &annotation_len); + size = dump_microdescriptor(fd, md, &annotation_len); if (size < 0) { /* XXX handle errors from dump_microdescriptor() */ /* log? return -1? die? coredump the universe? */

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[tor/master] Check more error codes when writing microdescriptors.
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit 6905c1f60d2d0e658481df70fdcaa73251becacc Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Mar 11 14:50:41 2013 -0400 Check more error codes when writing microdescriptors. Possible partial fix, or diagnosis tool, for bug 8031. --- changes/bug8031 | 7 +++++++ src/or/microdesc.c | 18 ++++++++++++++---- 2 files changed, 21 insertions(+), 4 deletions(-) diff --git a/changes/bug8031 b/changes/bug8031 new file mode 100644 index 0000000..17329ec --- /dev/null +++ b/changes/bug8031 @@ -0,0 +1,7 @@ + o Minor bugfixes: + - Use direct writes rather than stdio when building microdescriptor + caches, in an attempt to mitigate bug 8031, or at least make it + less common. + - Warn more aggressively when flushing microdescriptors to a + microdescriptor cache fails, in an attempt to mitegate bug 8031, + or at least make it more diagnosable. diff --git a/src/or/microdesc.c b/src/or/microdesc.c index 0a9724f..7d3f631 100644 --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@ -251,8 +251,14 @@ microdescs_add_list_to_cache(microdesc_cache_t *cache, cache->total_len_seen += md->bodylen; } SMARTLIST_FOREACH_END(md); - if (fd >= 0) - finish_writing_to_file(open_file); /*XXX Check me.*/ + if (fd >= 0) { + if (finish_writing_to_file(open_file) < 0) { + log_warn(LD_DIR, "Error appending to microdescriptor file: %s", + strerror(errno)); + smartlist_clear(added); + return added; + } + } { networkstatus_t *ns = networkstatus_get_latest_consensus(); @@ -459,11 +465,15 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) smartlist_add(wrote, md); } + if (finish_writing_to_file(open_file) < 0) { + log_warn(LD_DIR, "Error rebuilding microdescriptor cache: %s", + strerror(errno)); + return -1; + } + if (cache->cache_content) tor_munmap_file(cache->cache_content); - finish_writing_to_file(open_file); /*XXX Check me.*/ - cache->cache_content = tor_mmap_file(cache->cache_fname); if (!cache->cache_content && smartlist_len(wrote)) {

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[tor/master] Another possible diagnostic for 8031.
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit 1eebb566911380c22768a8d25061a8f917688349 Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Mar 11 14:52:56 2013 -0400 Another possible diagnostic for 8031. This time, I'm checking whether our calculated offset matches our real offset, in each case, as we go along. I don't think this is the bug, but it can't hurt to check. --- src/or/microdesc.c | 10 +++++++++- 1 files changed, 9 insertions(+), 1 deletions(-) diff --git a/src/or/microdesc.c b/src/or/microdesc.c index 7d3f631..bb9668d 100644 --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@ -415,7 +415,7 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) microdesc_t **mdp; smartlist_t *wrote; ssize_t size; - off_t off = 0; + off_t off = 0, off_real; int orig_size, new_size; if (cache == NULL) { @@ -458,6 +458,14 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) tor_assert(((size_t)size) == annotation_len + md->bodylen); md->off = off + annotation_len; off += size; + off_real = tor_fd_getpos(fd); + if (off_real != off) { + log_warn(LD_BUG, "Discontinuity in position in microdescriptor cache." + "By my count, I'm at "I64_FORMAT + ", but I should be at "I64_FORMAT, + I64_PRINTF_ARG(off), I64_PRINTF_ARG(off_real)); + off = off_real; + } if (md->saved_location != SAVED_IN_CACHE) { tor_free(md->body); md->saved_location = SAVED_IN_CACHE;

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[tor/master] Merge remote-tracking branch 'public/bug8031' into maint-0.2.4
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit de7e99f8bbc17bfaea260c6d8e2217678b5152af Merge: 4eaca17 1eebb56 Author: Nick Mathewson <nickm(a)torproject.org> Date: Tue Mar 19 14:18:07 2013 -0400 Merge remote-tracking branch 'public/bug8031' into maint-0.2.4 changes/bug8031 | 7 +++++ src/or/microdesc.c | 66 +++++++++++++++++++++++++++++++++------------------- 2 files changed, 49 insertions(+), 24 deletions(-) diff --cc src/or/microdesc.c index ac48930,bb9668d..f9dbcac --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@@ -228,11 -227,11 +228,11 @@@ microdescs_add_list_to_cache(microdesc_ } /* Okay, it's a new one. */ - if (f) { + if (fd >= 0) { size_t annotation_len; - size = dump_microdescriptor(f, md, &annotation_len); + size = dump_microdescriptor(fd, md, &annotation_len); if (size < 0) { - /* we already warned in dump_microdescriptor; */ + /* we already warned in dump_microdescriptor */ abort_writing_to_file(open_file); smartlist_clear(added); return added;

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[tor/master] Merge remote-tracking branch 'origin/maint-0.2.4'
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit 084c857704209572ca3dc9ffe8c1213189e35442 Merge: e6602f5 de7e99f Author: Nick Mathewson <nickm(a)torproject.org> Date: Tue Mar 19 14:19:19 2013 -0400 Merge remote-tracking branch 'origin/maint-0.2.4' changes/bug8031 | 7 +++++ src/or/microdesc.c | 66 +++++++++++++++++++++++++++++++++------------------- 2 files changed, 49 insertions(+), 24 deletions(-)

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[tor/maint-0.2.4] Use fds, not stdio, to manage microdescriptor files
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit d54ccbe9fd5c9ca6ff53ad7d0efc4d0e837062ab Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Mar 11 14:37:44 2013 -0400 Use fds, not stdio, to manage microdescriptor files This is part of an attempt to mitigate 8031. --- src/or/microdesc.c | 40 ++++++++++++++++++++-------------------- 1 files changed, 20 insertions(+), 20 deletions(-) diff --git a/src/or/microdesc.c b/src/or/microdesc.c index b4d22c1..0a9724f 100644 --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@ -70,7 +70,7 @@ HT_GENERATE(microdesc_map, microdesc_t, node, * *annotation_len_out to the number of bytes written as * annotations. */ static ssize_t -dump_microdescriptor(FILE *f, microdesc_t *md, size_t *annotation_len_out) +dump_microdescriptor(int fd, microdesc_t *md, size_t *annotation_len_out) { ssize_t r = 0; size_t written; @@ -80,10 +80,10 @@ dump_microdescriptor(FILE *f, microdesc_t *md, size_t *annotation_len_out) char annotation[ISO_TIME_LEN+32]; format_iso_time(buf, md->last_listed); tor_snprintf(annotation, sizeof(annotation), "@last-listed %s\n", buf); - if (fputs(annotation, f) < 0) { + if (write_all(fd, annotation, strlen(annotation), 0) < 0) { log_warn(LD_DIR, "Couldn't write microdescriptor annotation: %s", - strerror(ferror(f))); + strerror(errno)); return -1; } r += strlen(annotation); @@ -92,13 +92,13 @@ dump_microdescriptor(FILE *f, microdesc_t *md, size_t *annotation_len_out) *annotation_len_out = 0; } - md->off = (off_t) ftell(f); - written = fwrite(md->body, 1, md->bodylen, f); + md->off = tor_fd_getpos(fd); + written = write_all(fd, md->body, md->bodylen, 0); if (written != md->bodylen) { log_warn(LD_DIR, "Couldn't dump microdescriptor (wrote %lu out of %lu): %s", (unsigned long)written, (unsigned long)md->bodylen, - strerror(ferror(f))); + strerror(errno)); return -1; } r += md->bodylen; @@ -197,15 +197,15 @@ microdescs_add_list_to_cache(microdesc_cache_t *cache, { smartlist_t *added; open_file_t *open_file = NULL; - FILE *f = NULL; + int fd = -1; // int n_added = 0; ssize_t size = 0; if (where == SAVED_NOWHERE && !no_save) { - f = start_writing_to_stdio_file(cache->journal_fname, - OPEN_FLAGS_APPEND|O_BINARY, - 0600, &open_file); - if (!f) { + fd = start_writing_to_file(cache->journal_fname, + OPEN_FLAGS_APPEND|O_BINARY, + 0600, &open_file); + if (fd < 0) { log_warn(LD_DIR, "Couldn't append to journal in %s: %s", cache->journal_fname, strerror(errno)); return NULL; @@ -227,9 +227,9 @@ microdescs_add_list_to_cache(microdesc_cache_t *cache, } /* Okay, it's a new one. */ - if (f) { + if (fd >= 0) { size_t annotation_len; - size = dump_microdescriptor(f, md, &annotation_len); + size = dump_microdescriptor(fd, md, &annotation_len); if (size < 0) { /* we already warned in dump_microdescriptor; */ abort_writing_to_file(open_file); @@ -251,7 +251,7 @@ microdescs_add_list_to_cache(microdesc_cache_t *cache, cache->total_len_seen += md->bodylen; } SMARTLIST_FOREACH_END(md); - if (f) + if (fd >= 0) finish_writing_to_file(open_file); /*XXX Check me.*/ { @@ -405,7 +405,7 @@ int microdesc_cache_rebuild(microdesc_cache_t *cache, int force) { open_file_t *open_file; - FILE *f; + int fd = -1; microdesc_t **mdp; smartlist_t *wrote; ssize_t size; @@ -429,10 +429,10 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) orig_size = (int)(cache->cache_content ? cache->cache_content->size : 0); orig_size += (int)cache->journal_len; - f = start_writing_to_stdio_file(cache->cache_fname, - OPEN_FLAGS_REPLACE|O_BINARY, - 0600, &open_file); - if (!f) + fd = start_writing_to_file(cache->cache_fname, + OPEN_FLAGS_REPLACE|O_BINARY, + 0600, &open_file); + if (fd < 0) return -1; wrote = smartlist_new(); @@ -443,7 +443,7 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) if (md->no_save) continue; - size = dump_microdescriptor(f, md, &annotation_len); + size = dump_microdescriptor(fd, md, &annotation_len); if (size < 0) { /* XXX handle errors from dump_microdescriptor() */ /* log? return -1? die? coredump the universe? */

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[tor/maint-0.2.4] Check more error codes when writing microdescriptors.
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit 6905c1f60d2d0e658481df70fdcaa73251becacc Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Mar 11 14:50:41 2013 -0400 Check more error codes when writing microdescriptors. Possible partial fix, or diagnosis tool, for bug 8031. --- changes/bug8031 | 7 +++++++ src/or/microdesc.c | 18 ++++++++++++++---- 2 files changed, 21 insertions(+), 4 deletions(-) diff --git a/changes/bug8031 b/changes/bug8031 new file mode 100644 index 0000000..17329ec --- /dev/null +++ b/changes/bug8031 @@ -0,0 +1,7 @@ + o Minor bugfixes: + - Use direct writes rather than stdio when building microdescriptor + caches, in an attempt to mitigate bug 8031, or at least make it + less common. + - Warn more aggressively when flushing microdescriptors to a + microdescriptor cache fails, in an attempt to mitegate bug 8031, + or at least make it more diagnosable. diff --git a/src/or/microdesc.c b/src/or/microdesc.c index 0a9724f..7d3f631 100644 --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@ -251,8 +251,14 @@ microdescs_add_list_to_cache(microdesc_cache_t *cache, cache->total_len_seen += md->bodylen; } SMARTLIST_FOREACH_END(md); - if (fd >= 0) - finish_writing_to_file(open_file); /*XXX Check me.*/ + if (fd >= 0) { + if (finish_writing_to_file(open_file) < 0) { + log_warn(LD_DIR, "Error appending to microdescriptor file: %s", + strerror(errno)); + smartlist_clear(added); + return added; + } + } { networkstatus_t *ns = networkstatus_get_latest_consensus(); @@ -459,11 +465,15 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) smartlist_add(wrote, md); } + if (finish_writing_to_file(open_file) < 0) { + log_warn(LD_DIR, "Error rebuilding microdescriptor cache: %s", + strerror(errno)); + return -1; + } + if (cache->cache_content) tor_munmap_file(cache->cache_content); - finish_writing_to_file(open_file); /*XXX Check me.*/ - cache->cache_content = tor_mmap_file(cache->cache_fname); if (!cache->cache_content && smartlist_len(wrote)) {

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[tor/maint-0.2.4] Another possible diagnostic for 8031.
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit 1eebb566911380c22768a8d25061a8f917688349 Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Mar 11 14:52:56 2013 -0400 Another possible diagnostic for 8031. This time, I'm checking whether our calculated offset matches our real offset, in each case, as we go along. I don't think this is the bug, but it can't hurt to check. --- src/or/microdesc.c | 10 +++++++++- 1 files changed, 9 insertions(+), 1 deletions(-) diff --git a/src/or/microdesc.c b/src/or/microdesc.c index 7d3f631..bb9668d 100644 --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@ -415,7 +415,7 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) microdesc_t **mdp; smartlist_t *wrote; ssize_t size; - off_t off = 0; + off_t off = 0, off_real; int orig_size, new_size; if (cache == NULL) { @@ -458,6 +458,14 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force) tor_assert(((size_t)size) == annotation_len + md->bodylen); md->off = off + annotation_len; off += size; + off_real = tor_fd_getpos(fd); + if (off_real != off) { + log_warn(LD_BUG, "Discontinuity in position in microdescriptor cache." + "By my count, I'm at "I64_FORMAT + ", but I should be at "I64_FORMAT, + I64_PRINTF_ARG(off), I64_PRINTF_ARG(off_real)); + off = off_real; + } if (md->saved_location != SAVED_IN_CACHE) { tor_free(md->body); md->saved_location = SAVED_IN_CACHE;

1 0

[tor/maint-0.2.4] Merge remote-tracking branch 'public/bug8031' into maint-0.2.4
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit de7e99f8bbc17bfaea260c6d8e2217678b5152af Merge: 4eaca17 1eebb56 Author: Nick Mathewson <nickm(a)torproject.org> Date: Tue Mar 19 14:18:07 2013 -0400 Merge remote-tracking branch 'public/bug8031' into maint-0.2.4 changes/bug8031 | 7 +++++ src/or/microdesc.c | 66 +++++++++++++++++++++++++++++++++------------------- 2 files changed, 49 insertions(+), 24 deletions(-) diff --cc src/or/microdesc.c index ac48930,bb9668d..f9dbcac --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@@ -228,11 -227,11 +228,11 @@@ microdescs_add_list_to_cache(microdesc_ } /* Okay, it's a new one. */ - if (f) { + if (fd >= 0) { size_t annotation_len; - size = dump_microdescriptor(f, md, &annotation_len); + size = dump_microdescriptor(fd, md, &annotation_len); if (size < 0) { - /* we already warned in dump_microdescriptor; */ + /* we already warned in dump_microdescriptor */ abort_writing_to_file(open_file); smartlist_clear(added); return added;

1 0

[tor/master] On END_REASON_EXITPOLICY, mark circuit as unusable for that address.
by nickm＠torproject.org 19 Mar '13

19 Mar '13

commit 2b22c0aeef6e71d56b12411d10484aaece769178 Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Mar 11 23:37:47 2013 -0400 On END_REASON_EXITPOLICY, mark circuit as unusable for that address. Also, don't call the exit node 'reject *' unless our decision to pick that node was based on a non-summarized version of that node's exit policy. rransom and arma came up with the ideas for this fix. Fix for 7582; the summary-related part is a bugfix on 0.2.3.2-alpha. --- changes/bug7582 | 9 ++++++ src/or/circuituse.c | 13 +++++++-- src/or/nodelist.c | 18 +++++++++++++ src/or/nodelist.h | 1 + src/or/or.h | 4 +++ src/or/policies.c | 18 +++++++++++++ src/or/policies.h | 2 + src/or/relay.c | 68 ++++++++++++++++++++++++++++++++++++++++---------- 8 files changed, 116 insertions(+), 17 deletions(-) diff --git a/changes/bug7582 b/changes/bug7582 new file mode 100644 index 0000000..f3b0635 --- /dev/null +++ b/changes/bug7582 @@ -0,0 +1,9 @@ + o Major bugfixes: + + - When an exit node tells us that it is rejecting because of its + exit policy a stream we expected it to accept (because of its exit + policy), do not mark the node as useless for exiting if our + expectation was only based on an exit policy summary. Instead, + mark the circuit as unsuitable for that particular address. Fixes + part of bug 7582; bugfix on 0.2.3.2-alpha. + diff --git a/src/or/circuituse.c b/src/or/circuituse.c index 51d8716..6b5ca90 100644 --- a/src/or/circuituse.c +++ b/src/or/circuituse.c @@ -105,6 +105,8 @@ circuit_is_acceptable(const origin_circuit_t *origin_circ, return 0; if (purpose == CIRCUIT_PURPOSE_C_GENERAL) { + tor_addr_t addr; + const int family = tor_addr_parse(&addr, conn->socks_request->address); if (!exitnode && !build_state->onehop_tunnel) { log_debug(LD_CIRC,"Not considering circuit with unknown router."); return 0; /* this circuit is screwed and doesn't know it yet, @@ -125,9 +127,7 @@ circuit_is_acceptable(const origin_circuit_t *origin_circ, return 0; /* this is a circuit to somewhere else */ if (tor_digest_is_zero(digest)) { /* we don't know the digest; have to compare addr:port */ - tor_addr_t addr; - int r = tor_addr_parse(&addr, conn->socks_request->address); - if (r < 0 || + if (family < 0 || !tor_addr_eq(&build_state->chosen_exit->addr, &addr) || build_state->chosen_exit->port != conn->socks_request->port) return 0; @@ -139,6 +139,13 @@ circuit_is_acceptable(const origin_circuit_t *origin_circ, return 0; } } + if (origin_circ->prepend_policy && family != -1) { + int r = compare_tor_addr_to_addr_policy(&addr, + conn->socks_request->port, + origin_circ->prepend_policy); + if (r == ADDR_POLICY_REJECTED) + return 0; + } if (exitnode && !connection_ap_can_use_exit(conn, exitnode)) { /* can't exit from this router */ return 0; diff --git a/src/or/nodelist.c b/src/or/nodelist.c index ee1bc39..5f3b843 100644 --- a/src/or/nodelist.c +++ b/src/or/nodelist.c @@ -688,6 +688,24 @@ node_exit_policy_rejects_all(const node_t *node) return 1; } +/** Return true iff the exit policy for node is such that we can treat + * rejecting an address of type family unexpectedly as a sign of that + * node's failure. */ +int +node_exit_policy_is_exact(const node_t *node, sa_family_t family) +{ + if (family == AF_UNSPEC) { + return 1; /* Rejecting an address but not telling us what address + * is a bad sign. */ + } else if (family == AF_INET) { + return node->ri != NULL; + } else if (family == AF_INET6) { + return 0; + } + tor_fragile_assert(); + return 1; +} + /** Return list of tor_addr_port_t with all OR ports (in the sense IP * addr + TCP port) for node. Caller must free all elements * using tor_free() and free the list using smartlist_free(). diff --git a/src/or/nodelist.h b/src/or/nodelist.h index 65cf0d0..8a4665a 100644 --- a/src/or/nodelist.h +++ b/src/or/nodelist.h @@ -41,6 +41,7 @@ int node_get_purpose(const node_t *node); (node_get_purpose((node)) == ROUTER_PURPOSE_BRIDGE) int node_is_me(const node_t *node); int node_exit_policy_rejects_all(const node_t *node); +int node_exit_policy_is_exact(const node_t *node, sa_family_t family); smartlist_t *node_get_all_orports(const node_t *node); int node_allows_single_hop_exits(const node_t *node); const char *node_get_nickname(const node_t *node); diff --git a/src/or/or.h b/src/or/or.h index c7d2598..c893fba 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -3059,6 +3059,10 @@ typedef struct origin_circuit_t { * ISO_STREAM. */ uint64_t associated_isolated_stream_global_id; /**@}*/ + /** A list of addr_policy_t for this circuit in particular. Used by + * adjust_exit_policy_from_exitpolicy_failure. + */ + smartlist_t *prepend_policy; } origin_circuit_t; struct onion_queue_t; diff --git a/src/or/policies.c b/src/or/policies.c index 9696b81..be4da55 100644 --- a/src/or/policies.c +++ b/src/or/policies.c @@ -837,6 +837,24 @@ append_exit_policy_string(smartlist_t **policy, const char *more) } } +/** Add "reject addr:*" to dest, creating the list as needed. */ +void +addr_policy_append_reject_addr(smartlist_t **dest, const tor_addr_t *addr) +{ + addr_policy_t p, *add; + memset(&p, 0, sizeof(p)); + p.policy_type = ADDR_POLICY_REJECT; + p.maskbits = tor_addr_family(addr) == AF_INET6 ? 128 : 32; + tor_addr_copy(&p.addr, addr); + p.prt_min = 1; + p.prt_max = 65535; + + add = addr_policy_get_canonical_entry(&p); + if (!*dest) + *dest = smartlist_new(); + smartlist_add(*dest, add); +} + /** Detect and excise "dead code" from the policy *dest. */ static void exit_policy_remove_redundancies(smartlist_t *dest) diff --git a/src/or/policies.h b/src/or/policies.h index da375c4..c0e7a9e 100644 --- a/src/or/policies.h +++ b/src/or/policies.h @@ -47,6 +47,8 @@ int policies_parse_exit_policy(config_line_t *cfg, smartlist_t **dest, int rejectprivate, const char *local_address, int add_default_policy); void policies_exit_policy_append_reject_star(smartlist_t **dest); +void addr_policy_append_reject_addr(smartlist_t **dest, + const tor_addr_t *addr); void policies_set_node_exitpolicy_to_reject_all(node_t *exitrouter); int exit_policy_is_general_exit(smartlist_t *policy); int policy_is_reject_star(const smartlist_t *policy, sa_family_t family); diff --git a/src/or/relay.c b/src/or/relay.c index 9ff9e1e..a4f402d 100644 --- a/src/or/relay.c +++ b/src/or/relay.c @@ -53,6 +53,10 @@ static int circuit_resume_edge_reading_helper(edge_connection_t *conn, static int circuit_consider_stop_edge_reading(circuit_t *circ, crypt_path_t *layer_hint); static int circuit_queue_streams_are_blocked(circuit_t *circ); +static void adjust_exit_policy_from_exitpolicy_failure(origin_circuit_t *circ, + entry_connection_t *conn, + node_t *node, + const tor_addr_t *addr); /** Stop reading on edge connections when we have this many cells * waiting on the appropriate queue. */ @@ -710,7 +714,6 @@ connection_ap_process_end_not_open( relay_header_t *rh, cell_t *cell, origin_circuit_t *circ, entry_connection_t *conn, crypt_path_t *layer_hint) { - struct in_addr in; node_t *exitrouter; int reason = *(cell->payload+RELAY_HEADER_SIZE); int control_reason; @@ -753,10 +756,10 @@ connection_ap_process_end_not_open( stream_end_reason_to_string(reason)); exitrouter = node_get_mutable_by_id(chosen_exit_digest); switch (reason) { - case END_STREAM_REASON_EXITPOLICY: + case END_STREAM_REASON_EXITPOLICY: { + tor_addr_t addr; + tor_addr_make_unspec(&addr); if (rh->length >= 5) { - tor_addr_t addr; - int ttl = -1; tor_addr_make_unspec(&addr); if (rh->length == 5 || rh->length == 9) { @@ -808,16 +811,11 @@ connection_ap_process_end_not_open( } } /* check if he *ought* to have allowed it */ - if (exitrouter && - (rh->length < 5 || - (tor_inet_aton(conn->socks_request->address, &in) && - !conn->chosen_exit_name))) { - log_info(LD_APP, - "Exitrouter %s seems to be more restrictive than its exit " - "policy. Not using this router as exit for now.", - node_describe(exitrouter)); - policies_set_node_exitpolicy_to_reject_all(exitrouter); - } + + adjust_exit_policy_from_exitpolicy_failure(circ, + conn, + exitrouter, + &addr); if (conn->chosen_exit_optional || conn->chosen_exit_retries) { @@ -837,6 +835,7 @@ connection_ap_process_end_not_open( return 0; /* else, conn will get closed below */ break; + } case END_STREAM_REASON_CONNECTREFUSED: if (!conn->chosen_exit_optional) break; /* break means it'll close, below */ @@ -901,6 +900,47 @@ connection_ap_process_end_not_open( return 0; } +/** Called when we have gotten an END_REASON_EXITPOLICY failure on circ + * for conn, while attempting to connect via node. If the node + * told us which address it rejected, then addr is that address; + * otherwise it is AF_UNSPEC. + * + * If we are sure the node should have allowed this address, mark the node as + * having a reject *:* exit policy. Otherwise, mark the circuit as unusable + * for this particular address. + **/ +static void +adjust_exit_policy_from_exitpolicy_failure(origin_circuit_t *circ, + entry_connection_t *conn, + node_t *node, + const tor_addr_t *addr) +{ + int make_reject_all = 0; + const sa_family_t family = tor_addr_family(addr); + + if (node) { + tor_addr_t tmp; + int asked_for_family = tor_addr_parse(&tmp, conn->socks_request->address); + if (family == AF_UNSPEC) { + make_reject_all = 1; + } else if (node_exit_policy_is_exact(node, family) && + asked_for_family != -1 && !conn->chosen_exit_name) { + make_reject_all = 1; + } + + if (make_reject_all) { + log_info(LD_APP, + "Exitrouter %s seems to be more restrictive than its exit " + "policy. Not using this router as exit for now.", + node_describe(node)); + policies_set_node_exitpolicy_to_reject_all(node); + } + } + + if (family != AF_UNSPEC) + addr_policy_append_reject_addr(&circ->prepend_policy, addr); +} + /** Helper: change the socks_request->address field on conn to the * dotted-quad representation of new_addr, * and send an appropriate REMAP event. */

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