Fixes#209. A WS client socket closure could cause Webdis to schedule
the send of a closing frame, leading to both EV_READ and EV_WRITE
scheduled events. They would both fail and each lead to a call to
ws_client_free, causing a double free that ends in a crash.
http_parser.c has a table named "unhex" that it uses to convert hex
characters to their numeric values, e.g. 'F' -> 15. For non-hex
characters, the value is -1 but while the table contains int8_t values,
the extraction is done using a char. On ARMv8, char is *unsigned*, which
means it can't be compared to -1 as this is always false. Comparing to
(char)-1 instead will work.
Almost all header entries are guaranteed to be added only once, so we
don't need to check for duplicates all the time. In the current code
base only Content-Length has the potential for being added twice, and
even then it seems highly unlikely. For all others, we can now bypass
this check.
This commit also changes the header_copy flags to be 1-bit flags, so
that they can be combined.
Allocate the headers array once with the default number of entries
sufficient for most requests, and only re-allocate if needed instead of
re-allocating with each header.
http_response has an array of http_header key/value pairs, and most of
the time these use constant strings that do not need to be copied and
re-allocated. This change adds a flag tracking which values need to be
copied, were copied and need to be freed.
New feature: support for SSL connections to Redis.
Webdis can now connect securely to Redis, thanks to the Hiredis
client library. Docker images for Webdis will now contain two binaries,
"webdis" and "webdis-ssl", the latter depending on OpenSSL.
See Webdis README for details: https://github.com/nicolasff/webdis#configuring-webdis-with-ssl
Two binaries are built and packaged:
* /usr/local/bin/webdis -- still without SSL and does not depend on
OpenSSL
* /usr/local/bin/webdis-ssl -- supports SSL, depends on OpenSSL but has
to be used with the webdis image as a base image or in a container
injecting the webdis config and certs.
Security update: upgrading the version of Redis bundled in
the Webdis image to fix a number of severe vulnerabilities.
* Low severity vulnerability found in redis/redis
Description: Integer Overflow or Wraparound
Info: https://snyk.io/vuln/SNYK-ALPINE314-REDIS-1727801
Introduced through: redis/redis@6.2.5-r0
From: redis/redis@6.2.5-r0
Fixed in: 6.2.6-r0
* Medium severity vulnerability found in redis/redis
Description: Out-of-bounds Read
Info: https://snyk.io/vuln/SNYK-ALPINE314-REDIS-1727803
Introduced through: redis/redis@6.2.5-r0
From: redis/redis@6.2.5-r0
Fixed in: 6.2.6-r0
* High severity vulnerability found in redis/redis
Description: Allocation of Resources Without Limits or Throttling
Info: https://snyk.io/vuln/SNYK-ALPINE314-REDIS-1727783
Introduced through: redis/redis@6.2.5-r0
From: redis/redis@6.2.5-r0
Fixed in: 6.2.6-r0
* High severity vulnerability found in redis/redis
Description: CVE-2021-32626
Info: https://snyk.io/vuln/SNYK-ALPINE314-REDIS-1727820
Introduced through: redis/redis@6.2.5-r0
From: redis/redis@6.2.5-r0
Fixed in: 6.2.6-r0
* High severity vulnerability found in redis/redis
Description: Integer Overflow or Wraparound
Info: https://snyk.io/vuln/SNYK-ALPINE314-REDIS-1727822
Introduced through: redis/redis@6.2.5-r0
From: redis/redis@6.2.5-r0
Fixed in: 6.2.6-r0
* High severity vulnerability found in redis/redis
Description: Integer Overflow or Wraparound
Info: https://snyk.io/vuln/SNYK-ALPINE314-REDIS-1727823
Introduced through: redis/redis@6.2.5-r0
From: redis/redis@6.2.5-r0
Fixed in: 6.2.6-r0
* High severity vulnerability found in redis/redis
Description: Integer Overflow or Wraparound
Info: https://snyk.io/vuln/SNYK-ALPINE314-REDIS-1727825
Introduced through: redis/redis@6.2.5-r0
From: redis/redis@6.2.5-r0
Fixed in: 6.2.6-r0
* High severity vulnerability found in redis/redis
Description: Integer Overflow or Wraparound
Info: https://snyk.io/vuln/SNYK-ALPINE314-REDIS-1727826
Introduced through: redis/redis@6.2.5-r0
From: redis/redis@6.2.5-r0
Fixed in: 6.2.6-r0
* Many improvements to WebSocket implementation (#198, #199). WebSocket
support is now much more stable, and better tested. The feature is
still disabled by default, but is recommended for testing.
* Base image updated from Alpine 3.12.7 to 3.14.2 to resolve
vulnerabilities found in Alpine. Webdis itself is not at risk, but
images *based* on Webdis could be using vulnerable software if they
use packages from Alpine 3.12.7.
This is not really uninitialized, it would only happen if the string
dumped with dump_string was empty of contained invalid UTF-8. Setting
an initial value has no effect since codepoint is used as an "out"
value in utf8_iterate.
Also mark the WS client as closing before we close the Redis connection,
to avoid its last error callback (if sent) trying to send out data while
we're in the middle of freeing the client.
1. Introduce ws_client struct
2. Handle all communications from websocket.c for WS clients
3. Always use a dedicated Redis connection for WS clients
4. Add rbuf & wbuf evbuffers for incoming & outgoing WS data
5. Use event_base_once to control R/W events
6. WS test: make sure to read complete HTTP response
For WS clients, reuse a persistent cmd struct attached to the
http_client object: take the cmd built from the WS frame, and copy it to
the persistent cmd.
Jessie Murray
Nicolas Favre-Felix