File libssh-cmake-Add-option-WITH_HERMETIC_USR.patch of Package libssh
From d88dbc1e0fa6dab2de359f211792c0b5c3ec7664 Mon Sep 17 00:00:00 2001
From: Lucas Mulling <lucas.mulling@suse.com>
Date: Mon, 17 Feb 2025 14:13:53 -0300
Subject: [PATCH] cmake: Add option WITH_HERMETIC_USR
Add a cmake option to enable hermetic-usr, i.e., use of config files in /usr/.
If turned on, GLOBAL_*_CONFIG is prepended with /usr/ and defined as
USR_GLOBAL_*_CONFIG. Config lookup follows this path GLOBAL_*_CONFIG ->
USR_GLOBAL_*_CONFIG.
Introduce a ssh_config_parse primitive. This avoids convoluted checks for file
presence (without modifing the behaviour of ssh_config_parse_file) and allows
marking whether the config is global at the call site.
Signed-off-by: Lucas Mulling <lucas.mulling@suse.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
---
CMakeLists.txt | 8 ++-
DefineOptions.cmake | 6 +++
config.h.cmake | 2 +
include/libssh/libssh.h | 3 +-
include/libssh/options.h | 1 +
src/config.c | 56 ++++++++++++++-------
src/options.c | 106 ++++++++++++++++++++++++---------------
7 files changed, 122 insertions(+), 60 deletions(-)
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9877cd70..9a4ea9e3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -249,9 +249,15 @@ message(STATUS "Benchmarks: ${WITH_BENCHMARKS}")
message(STATUS "Symbol versioning: ${WITH_SYMBOL_VERSIONING}")
message(STATUS "Allow ABI break: ${WITH_ABI_BREAK}")
message(STATUS "Release is final: ${WITH_FINAL}")
+if (WITH_HERMETIC_USR)
+ message(STATUS "User global client config: ${USR_GLOBAL_CLIENT_CONFIG}")
+endif ()
message(STATUS "Global client config: ${GLOBAL_CLIENT_CONFIG}")
if (WITH_SERVER)
-message(STATUS "Global bind config: ${GLOBAL_BIND_CONFIG}")
+ if (WITH_HERMETIC_USR)
+ message(STATUS "User global bind config: ${USR_GLOBAL_BIND_CONFIG}")
+ endif ()
+ message(STATUS "Global bind config: ${GLOBAL_BIND_CONFIG}")
endif()
message(STATUS "********************************************")
diff --git a/DefineOptions.cmake b/DefineOptions.cmake
index f1a6a244..91bb96db 100644
--- a/DefineOptions.cmake
+++ b/DefineOptions.cmake
@@ -27,6 +27,7 @@ option(WITH_INSECURE_NONE "Enable insecure none cipher and MAC algorithms (not s
option(WITH_EXEC "Enable libssh to execute arbitrary commands from configuration files or options (match exec, proxy commands and OpenSSH-based proxy-jumps)." ON)
option(FUZZ_TESTING "Build with fuzzer for the server and client (automatically enables none cipher!)" OFF)
option(PICKY_DEVELOPER "Build with picky developer flags" OFF)
+option(WITH_HERMETIC_USR "Build with support for hermetic /usr/" OFF)
if (WITH_ZLIB)
set(WITH_LIBZ ON)
@@ -59,6 +60,11 @@ if (NOT GLOBAL_CLIENT_CONFIG)
set(GLOBAL_CLIENT_CONFIG "/etc/ssh/ssh_config")
endif (NOT GLOBAL_CLIENT_CONFIG)
+if (WITH_HERMETIC_USR)
+ set(USR_GLOBAL_BIND_CONFIG "/usr${GLOBAL_BIND_CONFIG}")
+ set(USR_GLOBAL_CLIENT_CONFIG "/usr${GLOBAL_CLIENT_CONFIG}")
+endif (WITH_HERMETIC_USR)
+
if (FUZZ_TESTING)
set(WITH_INSECURE_NONE ON)
endif (FUZZ_TESTING)
diff --git a/config.h.cmake b/config.h.cmake
index 8dce5273..b61ce1db 100644
--- a/config.h.cmake
+++ b/config.h.cmake
@@ -9,9 +9,11 @@
#cmakedefine SOURCEDIR "${SOURCEDIR}"
/* Global bind configuration file path */
+#cmakedefine USR_GLOBAL_BIND_CONFIG "${USR_GLOBAL_BIND_CONFIG}"
#cmakedefine GLOBAL_BIND_CONFIG "${GLOBAL_BIND_CONFIG}"
/* Global client configuration file path */
+#cmakedefine USR_GLOBAL_CLIENT_CONFIG "${USR_GLOBAL_CLIENT_CONFIG}"
#cmakedefine GLOBAL_CLIENT_CONFIG "${GLOBAL_CLIENT_CONFIG}"
/************************** HEADER FILES *************************/
diff --git a/include/libssh/libssh.h b/include/libssh/libssh.h
index 3bddb019..28fe7396 100644
--- a/include/libssh/libssh.h
+++ b/include/libssh/libssh.h
@@ -49,9 +49,10 @@
#endif
#endif
+#include <inttypes.h>
#include <stdarg.h>
+#include <stdbool.h>
#include <stdint.h>
-#include <inttypes.h>
#ifdef _MSC_VER
typedef int mode_t;
diff --git a/include/libssh/options.h b/include/libssh/options.h
index d32e1589..63b207fa 100644
--- a/include/libssh/options.h
+++ b/include/libssh/options.h
@@ -25,6 +25,7 @@
extern "C" {
#endif
+int ssh_config_parse(ssh_session session, FILE *fp, bool global);
int ssh_config_parse_file(ssh_session session, const char *filename);
int ssh_config_parse_string(ssh_session session, const char *input);
int ssh_options_set_algo(ssh_session session,
diff --git a/src/config.c b/src/config.c
index b4171efd..611c0349 100644
--- a/src/config.c
+++ b/src/config.c
@@ -1451,45 +1451,67 @@ ssh_config_parse_line(ssh_session session,
return 0;
}
-/* @brief Parse configuration file and set the options to the given session
+/* @brief Parse configuration from a file pointer
*
* @params[in] session The ssh session
- * @params[in] filename The path to the ssh configuration file
+ * @params[in] fp A valid file pointer
+ * @params[in] global Whether the config is global or not
*
* @returns 0 on successful parsing the configuration file, -1 on error
*/
-int ssh_config_parse_file(ssh_session session, const char *filename)
+int ssh_config_parse(ssh_session session, FILE *fp, bool global)
{
char line[MAX_LINE_SIZE] = {0};
unsigned int count = 0;
- FILE *f = NULL;
int parsing, rv;
+
+ parsing = 1;
+ while (fgets(line, sizeof(line), fp)) {
+ count++;
+ rv = ssh_config_parse_line(session, line, count, &parsing, 0, global);
+ if (rv < 0) {
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+/* @brief Parse configuration file and set the options to the given session
+ *
+ * @params[in] session The ssh session
+ * @params[in] filename The path to the ssh configuration file
+ *
+ * @returns 0 on successful parsing the configuration file, -1 on error
+ */
+int ssh_config_parse_file(ssh_session session, const char *filename)
+{
+ FILE *fp = NULL;
+ int rv;
bool global = 0;
- f = fopen(filename, "r");
- if (f == NULL) {
+ fp = fopen(filename, "r");
+ if (fp == NULL) {
return 0;
}
rv = strcmp(filename, GLOBAL_CLIENT_CONFIG);
+#ifdef USR_GLOBAL_CLIENT_CONFIG
+ if (rv != 0) {
+ rv = strcmp(filename, USR_GLOBAL_CLIENT_CONFIG);
+ }
+#endif
+
if (rv == 0) {
global = true;
}
SSH_LOG(SSH_LOG_PACKET, "Reading configuration data from %s", filename);
- parsing = 1;
- while (fgets(line, sizeof(line), f)) {
- count++;
- rv = ssh_config_parse_line(session, line, count, &parsing, 0, global);
- if (rv < 0) {
- fclose(f);
- return -1;
- }
- }
+ rv = ssh_config_parse(session, fp, global);
- fclose(f);
- return 0;
+ fclose(fp);
+ return rv;
}
/* @brief Parse configuration string and set the options to the given session
diff --git a/src/options.c b/src/options.c
index 785296dd..6a72e0e2 100644
--- a/src/options.c
+++ b/src/options.c
@@ -26,6 +26,7 @@
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <unistd.h>
#ifndef _WIN32
#include <pwd.h>
#else
@@ -1814,6 +1815,8 @@ int ssh_options_getopt(ssh_session session, int *argcptr, char **argv)
*
* @param filename The options file to use, if NULL the default
* ~/.ssh/config and /etc/ssh/ssh_config will be used.
+ * If complied with support for hermetic-usr,
+ * /usr/etc/ssh/ssh_config will be used last.
*
* @return 0 on success, < 0 on error.
*
@@ -1821,48 +1824,63 @@ int ssh_options_getopt(ssh_session session, int *argcptr, char **argv)
*/
int ssh_options_parse_config(ssh_session session, const char *filename)
{
- char *expanded_filename = NULL;
- int r;
+ char *expanded_filename = NULL;
+ int r;
+ FILE *fp = NULL;
- if (session == NULL) {
- return -1;
- }
- if (session->opts.host == NULL) {
- ssh_set_error_invalid(session);
- return -1;
- }
-
- if (session->opts.sshdir == NULL) {
- r = ssh_options_set(session, SSH_OPTIONS_SSH_DIR, NULL);
- if (r < 0) {
- ssh_set_error_oom(session);
- return -1;
- }
- }
-
- /* set default filename */
- if (filename == NULL) {
- expanded_filename = ssh_path_expand_escape(session, "%d/config");
- } else {
- expanded_filename = ssh_path_expand_escape(session, filename);
- }
- if (expanded_filename == NULL) {
- return -1;
- }
-
- r = ssh_config_parse_file(session, expanded_filename);
- if (r < 0) {
- goto out;
- }
- if (filename == NULL) {
- r = ssh_config_parse_file(session, GLOBAL_CLIENT_CONFIG);
- }
-
- /* Do not process the default configuration as part of connection again */
- session->opts.config_processed = true;
+ if (session == NULL) {
+ return -1;
+ }
+ if (session->opts.host == NULL) {
+ ssh_set_error_invalid(session);
+ return -1;
+ }
+
+ if (session->opts.sshdir == NULL) {
+ r = ssh_options_set(session, SSH_OPTIONS_SSH_DIR, NULL);
+ if (r < 0) {
+ ssh_set_error_oom(session);
+ return -1;
+ }
+ }
+
+ /* set default filename */
+ if (filename == NULL) {
+ expanded_filename = ssh_path_expand_escape(session, "%d/config");
+ } else {
+ expanded_filename = ssh_path_expand_escape(session, filename);
+ }
+ if (expanded_filename == NULL) {
+ return -1;
+ }
+
+ r = ssh_config_parse_file(session, expanded_filename);
+ if (r < 0) {
+ goto out;
+ }
+ if (filename == NULL) {
+ if ((fp = fopen(GLOBAL_CLIENT_CONFIG, "r")) != NULL) {
+ filename = GLOBAL_CLIENT_CONFIG;
+#ifdef USR_GLOBAL_CLIENT_CONFIG
+ } else if ((fp = fopen(USR_GLOBAL_CLIENT_CONFIG, "r")) != NULL) {
+ filename = USR_GLOBAL_CLIENT_CONFIG;
+#endif
+ }
+
+ if (fp) {
+ SSH_LOG(SSH_LOG_PACKET,
+ "Reading configuration data from %s",
+ filename);
+ r = ssh_config_parse(session, fp, true);
+ fclose(fp);
+ }
+ }
+
+ /* Do not process the default configuration as part of connection again */
+ session->opts.config_processed = true;
out:
- free(expanded_filename);
- return r;
+ free(expanded_filename);
+ return r;
}
int ssh_options_apply(ssh_session session)
@@ -2706,7 +2724,13 @@ int ssh_bind_options_parse_config(ssh_bind sshbind, const char *filename)
/* If the global default configuration hasn't been processed yet, process it
* before the provided configuration. */
if (!(sshbind->config_processed)) {
- rc = ssh_bind_config_parse_file(sshbind, GLOBAL_BIND_CONFIG);
+ if (access(GLOBAL_BIND_CONFIG, F_OK) == 0) {
+ rc = ssh_bind_config_parse_file(sshbind, GLOBAL_BIND_CONFIG);
+#ifdef USR_GLOBAL_BIND_CONFIG
+ } else {
+ rc = ssh_bind_config_parse_file(sshbind, USR_GLOBAL_BIND_CONFIG);
+#endif
+ }
if (rc != 0) {
return rc;
}
--
2.50.0
