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The supported protocols depend on the version of <span class=\"productname\">OpenSSL</span> used, older versions not supporting the most modern protocol versions. If not specified, the default is <code class=\"literal\">TLSv1.2</code>, which satisfies industry best practices as of this writing.</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSL-MIN-PROTOCOL-VERSION", "source_option": {"keyword": "ssl_min_protocol_version", "declaration": "\"ssl_min_protocol_version\", \"PGSSLMINPROTOCOLVERSION\", \"TLSv1.2\", NULL, \"SSL-Minimum-Protocol-Version\", \"\", 8, offsetof(struct pg_conn, ssl_min_protocol_version)", "environment": "PGSSLMINPROTOCOLVERSION", "source_notes": [], "compiled_default_expression": "\"TLSv1.2\""}, "comparison_data": {"keyword": "ssl_min_protocol_version", "definition": "This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMINPROTOCOLVERSION behaves the same as the ssl_min_protocol_version connection parameter."]}], "signature": "ssl_min_protocol_version", "documented": true, "description": ["This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing."], "environment": [{"name": "PGSSLMINPROTOCOLVERSION", "source_url": "/docs/16/libpq-envars.html", "description": "PGSSLMINPROTOCOLVERSION behaves the same as the ssl_min_protocol_version connection parameter."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-SSL-MIN-PROTOCOL-VERSION\"><span class=\"term\"><code class=\"literal\">ssl_min_protocol_version</code></span> </dt><dd>\n<p>This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are <code class=\"literal\">TLSv1</code>, <code class=\"literal\">TLSv1.1</code>, <code class=\"literal\">TLSv1.2</code> and <code class=\"literal\">TLSv1.3</code>. The supported protocols depend on the version of <span class=\"productname\">OpenSSL</span> used, older versions not supporting the most modern protocol versions. If not specified, the default is <code class=\"literal\">TLSv1.2</code>, which satisfies industry best practices as of this writing.</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSL-MIN-PROTOCOL-VERSION", "source_option": {"keyword": "ssl_min_protocol_version", "declaration": "\"ssl_min_protocol_version\", \"PGSSLMINPROTOCOLVERSION\", \"TLSv1.2\", NULL, \"SSL-Minimum-Protocol-Version\", \"\", 8, offsetof(struct pg_conn, ssl_min_protocol_version)", "environment": "PGSSLMINPROTOCOLVERSION", "source_notes": [], "compiled_default_expression": "\"TLSv1.2\""}, "comparison_data": {"keyword": "ssl_min_protocol_version", "definition": "This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing.", "documented": true, "environment": "PGSSLMINPROTOCOLVERSION", "default_evidence": ["This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing."], "compiled_default_expression": "\"TLSv1.2\""}, "comparison_hash": "1bde3a5ef74c2c30ca78fc953caf88f143fc0f4ef6651c577120fadafcee565a", "default_evidence": ["This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMINPROTOCOLVERSION behaves the same as the ssl_min_protocol_version connection parameter."]}], "signature": "ssl_min_protocol_version", "documented": true, "description": ["This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing."], "environment": [{"name": "PGSSLMINPROTOCOLVERSION", "source_url": "/docs/17/libpq-envars.html", "description": "PGSSLMINPROTOCOLVERSION behaves the same as the ssl_min_protocol_version connection parameter."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-SSL-MIN-PROTOCOL-VERSION\"><span class=\"term\"><code class=\"literal\">ssl_min_protocol_version</code></span> </dt><dd>\n<p>This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are <code class=\"literal\">TLSv1</code>, <code class=\"literal\">TLSv1.1</code>, <code class=\"literal\">TLSv1.2</code> and <code class=\"literal\">TLSv1.3</code>. The supported protocols depend on the version of <span class=\"productname\">OpenSSL</span> used, older versions not supporting the most modern protocol versions. If not specified, the default is <code class=\"literal\">TLSv1.2</code>, which satisfies industry best practices as of this writing.</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSL-MIN-PROTOCOL-VERSION", "source_option": {"keyword": "ssl_min_protocol_version", "declaration": "\"ssl_min_protocol_version\", \"PGSSLMINPROTOCOLVERSION\", \"TLSv1.2\", NULL, \"SSL-Minimum-Protocol-Version\", \"\", 8, offsetof(struct pg_conn, ssl_min_protocol_version)", "environment": "PGSSLMINPROTOCOLVERSION", "source_notes": [], "compiled_default_expression": "\"TLSv1.2\""}, "comparison_data": {"keyword": "ssl_min_protocol_version", "definition": "This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMINPROTOCOLVERSION behaves the same as the ssl_min_protocol_version connection parameter."]}], "signature": "ssl_min_protocol_version", "documented": true, "description": ["This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing."], "environment": [{"name": "PGSSLMINPROTOCOLVERSION", "source_url": "/docs/18/libpq-envars.html", "description": "PGSSLMINPROTOCOLVERSION behaves the same as the ssl_min_protocol_version connection parameter."}], "manual_html": "<div><dl class=\"variablelist\"><dt id=\"LIBPQ-CONNECT-SSL-MIN-PROTOCOL-VERSION\"><span class=\"term\"><code class=\"literal\">ssl_min_protocol_version</code></span> </dt><dd>\n<p>This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are <code class=\"literal\">TLSv1</code>, <code class=\"literal\">TLSv1.1</code>, <code class=\"literal\">TLSv1.2</code> and <code class=\"literal\">TLSv1.3</code>. The supported protocols depend on the version of <span class=\"productname\">OpenSSL</span> used, older versions not supporting the most modern protocol versions. If not specified, the default is <code class=\"literal\">TLSv1.2</code>, which satisfies industry best practices as of this writing.</p>\n</dd></dl></div>", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSL-MIN-PROTOCOL-VERSION", "source_option": {"keyword": "ssl_min_protocol_version", "declaration": "\"ssl_min_protocol_version\", \"PGSSLMINPROTOCOLVERSION\", \"TLSv1.2\", NULL, \"SSL-Minimum-Protocol-Version\", \"\", 8, offsetof(struct pg_conn, ssl_min_protocol_version)", "environment": "PGSSLMINPROTOCOLVERSION", "source_notes": [], "compiled_default_expression": "\"TLSv1.2\""}, "comparison_data": {"keyword": "ssl_min_protocol_version", "definition": "This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing.", "documented": true, "environment": "PGSSLMINPROTOCOLVERSION", "default_evidence": ["This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing."], "compiled_default_expression": "\"TLSv1.2\""}, "comparison_hash": "1bde3a5ef74c2c30ca78fc953caf88f143fc0f4ef6651c577120fadafcee565a", "default_evidence": ["This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing."], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "comparison": {"left": "12", "right": "13", "status": "added", "diff": "--- PostgreSQL 12\n+++ PostgreSQL 13\n@@ -1 +1,10 @@\n-Not recorded in this version\n+{\n+  \"compiled_default_expression\": \"\\\"TLSv1.2\\\"\",\n+  \"default_evidence\": [\n+    \"This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing.\"\n+  ],\n+  \"definition\": \"This parameter specifies the minimum SSL/TLS protocol version to allow for the connection. Valid values are TLSv1 , TLSv1.1 , TLSv1.2 and TLSv1.3 . The supported protocols depend on the version of OpenSSL used, older versions not supporting the most modern protocol versions. If not specified, the default is TLSv1.2 , which satisfies industry best practices as of this writing.\",\n+  \"documented\": true,\n+  \"environment\": \"PGSSLMINPROTOCOLVERSION\",\n+  \"keyword\": \"ssl_min_protocol_version\"\n+}"}}