diff options
Diffstat (limited to 'src/or/protover.c')
| -rw-r--r-- | src/or/protover.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/src/or/protover.c b/src/or/protover.c index 6532f09c2f..811f91410f 100644 --- a/src/or/protover.c +++ b/src/or/protover.c @@ -53,6 +53,11 @@ static const struct { #define N_PROTOCOL_NAMES ARRAY_LENGTH(PROTOCOL_NAMES) +/* Maximum allowed length of any single subprotocol name. */ +// C_RUST_COUPLED: src/rust/protover/protover.rs +// `MAX_PROTOCOL_NAME_LENGTH` +static const uint MAX_PROTOCOL_NAME_LENGTH = 100; + /** * Given a protocol_type_t, return the corresponding string used in * descriptors. @@ -198,6 +203,15 @@ parse_single_entry(const char *s, const char *end_of_entry) if (equals == s) goto error; + /* The name must not be longer than MAX_PROTOCOL_NAME_LENGTH. */ + if (equals - s > MAX_PROTOCOL_NAME_LENGTH) { + log_warn(LD_NET, "When parsing a protocol entry, I got a very large " + "protocol name. This is possibly an attack or a bug, unless " + "the Tor network truly supports protocol names larger than " + "%ud characters. The offending string was: %s", + MAX_PROTOCOL_NAME_LENGTH, escaped(out->name)); + goto error; + } out->name = tor_strndup(s, equals-s); tor_assert(equals < end_of_entry); @@ -263,6 +277,18 @@ parse_protocol_list(const char *s) } /** + * Return true if the unparsed protover in <b>s</b> would contain a protocol + * name longer than MAX_PROTOCOL_NAME_LENGTH, and false otherwise. + */ +bool +protover_contains_long_protocol_names(const char *s) +{ + if (!parse_protocol_list(s)) + return true; + return false; +} + +/** * Given a protocol type and version number, return true iff we know * how to speak that protocol. */ @@ -439,6 +465,14 @@ expand_protocol_list(const smartlist_t *protos) SMARTLIST_FOREACH_BEGIN(protos, const proto_entry_t *, ent) { const char *name = ent->name; + if (strlen(name) > MAX_PROTOCOL_NAME_LENGTH) { + log_warn(LD_NET, "When expanding a protocol entry, I got a very large " + "protocol name. This is possibly an attack or a bug, unless " + "the Tor network truly supports protocol names larger than " + "%ud characters. The offending string was: %s", + MAX_PROTOCOL_NAME_LENGTH, escaped(name)); + continue; + } SMARTLIST_FOREACH_BEGIN(ent->ranges, const proto_range_t *, range) { uint32_t u; for (u = range->low; u <= range->high; ++u) { |