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Posted to commits@mina.apache.org by lg...@apache.org on 2021/03/05 09:26:13 UTC
[mina-sshd] 03/07: [SSHD-1133] Added capability to specify a custom
charset for returning environment variables related data from the ScpShell
This is an automated email from the ASF dual-hosted git repository.
lgoldstein pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/mina-sshd.git
commit 88aa3129b2336e0bfb9156cc4b71bd2bfc1196b4
Author: Lyor Goldstein <lg...@apache.org>
AuthorDate: Fri Feb 26 10:53:05 2021 +0200
[SSHD-1133] Added capability to specify a custom charset for returning environment variables related data from the ScpShell
---
CHANGES.md | 3 ++-
docs/scp.md | 2 ++
.../main/java/org/apache/sshd/scp/ScpModuleProperties.java | 7 +++++++
.../src/main/java/org/apache/sshd/scp/server/ScpShell.java | 13 +++++++++----
4 files changed, 20 insertions(+), 5 deletions(-)
diff --git a/CHANGES.md b/CHANGES.md
index 6de775d..df0eb3e 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -45,4 +45,5 @@
* [SSHD-1114](https://issues.apache.org/jira/browse/SSHD-1114) Added capability for interactive key based authentication participation via UserInteraction
* [SSHD-1125](https://issues.apache.org/jira/browse/SSHD-1125) Added mechanism to throttle pending write requests in BufferedIoOutputStream
* [SSHD-1127](https://issues.apache.org/jira/browse/SSHD-1127) Added capability to register a custom receiver for SFTP STDERR channel raw or stream data
-* [SSHD-1133](https://issues.apache.org/jira/browse/SSHD-1133) Added capability to specify a custom charset for parsing incoming commands to the `ScpShell`
\ No newline at end of file
+* [SSHD-1133](https://issues.apache.org/jira/browse/SSHD-1133) Added capability to specify a custom charset for parsing incoming commands to the `ScpShell`
+* [SSHD-1133](https://issues.apache.org/jira/browse/SSHD-1133) Added capability to specify a custom charset for returning environment variables related data from the `ScpShell`
\ No newline at end of file
diff --git a/docs/scp.md b/docs/scp.md
index 06364c1..96274b8 100644
--- a/docs/scp.md
+++ b/docs/scp.md
@@ -204,6 +204,8 @@ ScpModuleProperties.SHELL_NAME_DECODING_CHARSET.set(sshd, Charset.forName("US-AS
**Caveat emptor:** that the code does not enforce "symmetry" of the chosen character sets - in other words, user can either by design or error cause different encoding to be used for the incoming commands vs. the outgoing responses. It is important to bear in mind that if the text to be encoded/decoded contains characters that cannot be safely handled by the chosen encoder/decoder than the result might not be correctly parsed/understood by the peer.
+A similar behavior is controlled via `SHELL_ENVVARS_ENCODING_CHARSET` which controls responses from the `ScpShell` regarding environment variables - the main difference being that the default is US-ASCII rather than UTF-8.
+
## Remote-to-remote transfer
The code provides an `ScpTransferHelper` class that enables copying files between 2 remote accounts without going through
diff --git a/sshd-scp/src/main/java/org/apache/sshd/scp/ScpModuleProperties.java b/sshd-scp/src/main/java/org/apache/sshd/scp/ScpModuleProperties.java
index 4bdae9a..9f19e02 100644
--- a/sshd-scp/src/main/java/org/apache/sshd/scp/ScpModuleProperties.java
+++ b/sshd-scp/src/main/java/org/apache/sshd/scp/ScpModuleProperties.java
@@ -60,6 +60,13 @@ public final class ScpModuleProperties {
= Property.charset("scp-shell-name-encoding-charset", StandardCharsets.UTF_8);
/**
+ * Used to indicate the {@link Charset} (or its name) for handling environment values in {@code ScpShell} -
+ * extracted from the channel session when shell initialized.
+ */
+ public static final Property<Charset> SHELL_ENVVARS_ENCODING_CHARSET
+ = Property.charset("scp-shell-envvars-encoding-charset", StandardCharsets.US_ASCII);
+
+ /**
* Used to indicate the {@link Charset} (or its name) for decoding incoming commands to be processed by the
* {@code ScpShell} - extracted from the channel session when shell initialized.
*/
diff --git a/sshd-scp/src/main/java/org/apache/sshd/scp/server/ScpShell.java b/sshd-scp/src/main/java/org/apache/sshd/scp/server/ScpShell.java
index af31fbc..df4d433 100644
--- a/sshd-scp/src/main/java/org/apache/sshd/scp/server/ScpShell.java
+++ b/sshd-scp/src/main/java/org/apache/sshd/scp/server/ScpShell.java
@@ -90,6 +90,7 @@ public class ScpShell extends AbstractFileSystemCommand implements ServerChannel
protected final Map<String, Object> variables = new HashMap<>();
protected final Charset nameEncodingCharset;
+ protected final Charset envVarsEnodingCharset;
protected final ScpFileOpener opener;
protected final ScpTransferEventListener listener;
@@ -107,6 +108,7 @@ public class ScpShell extends AbstractFileSystemCommand implements ServerChannel
this.channelSession = Objects.requireNonNull(channelSession, "No channel session provided");
nameEncodingCharset = ScpModuleProperties.SHELL_NAME_ENCODING_CHARSET.getRequired(channelSession);
+ envVarsEnodingCharset = ScpModuleProperties.SHELL_ENVVARS_ENCODING_CHARSET.getRequired(channelSession);
if (sendSize < ScpHelper.MIN_SEND_BUFFER_SIZE) {
throw new IllegalArgumentException(
@@ -155,7 +157,7 @@ public class ScpShell extends AbstractFileSystemCommand implements ServerChannel
}
protected void signalError(String cmd, String errorMsg) {
- signalError(cmd, errorMsg, StandardCharsets.US_ASCII);
+ signalError(cmd, errorMsg, envVarsEnodingCharset);
}
protected void signalError(String cmd, String errorMsg, Charset cs) {
@@ -217,6 +219,7 @@ public class ScpShell extends AbstractFileSystemCommand implements ServerChannel
log.warn("run({}) {}", channel, message);
try {
OutputStream stderr = getErrorStream();
+ // Don't encode it with any user defined charset
stderr.write(message.getBytes(StandardCharsets.US_ASCII));
} catch (IOException ioe) {
log.warn("run({}) Failed ({}) to write error message={}: {}",
@@ -311,7 +314,9 @@ public class ScpShell extends AbstractFileSystemCommand implements ServerChannel
protected void handleUnsupportedCommand(String command, String[] argv) throws Exception {
log.warn("handleUnsupportedCommand({}) unsupported: {}", getServerChannelSession(), command);
variables.put(STATUS, 127);
- getErrorStream().write(("command not found: " + argv[0] + "\n").getBytes(StandardCharsets.US_ASCII));
+ OutputStream errorStream = getErrorStream();
+ // Don't encode it with any user defined charset
+ errorStream.write(("command not found: " + argv[0] + "\n").getBytes(StandardCharsets.US_ASCII));
}
protected List<String[]> parse(String command) {
@@ -366,7 +371,7 @@ public class ScpShell extends AbstractFileSystemCommand implements ServerChannel
if (argv.length == 1) {
envValues.entrySet()
.stream()
- .forEach(e -> println(argv[0], e.getKey() + "=" + e.getValue(), stdout, StandardCharsets.US_ASCII));
+ .forEach(e -> println(argv[0], e.getKey() + "=" + e.getValue(), stdout, envVarsEnodingCharset));
variables.put(STATUS, 0);
return;
}
@@ -387,7 +392,7 @@ public class ScpShell extends AbstractFileSystemCommand implements ServerChannel
log.debug("printenv({}) {}={}", getServerChannelSession(), varName, varValue);
}
- println(argv[0], varValue, stdout, StandardCharsets.US_ASCII);
+ println(argv[0], varValue, stdout, envVarsEnodingCharset);
variables.put(STATUS, 0);
}