Installation

pip install snmp

The simplest way to install snmp is with pip:

pip install snmp

Source Download

You can also download snmp directly from GitHub. Copy the snmp subdirectory to your desired installation location.

Customization

Nearly the entire snmp library is written exclusively in Python, using only the standard library. The only exception is the snmp.security.usm.priv module, which relies on third-party libraries to support encryption in SNMPv3. However, this module is considered optional; all other features in the library will work perfectly fine without it.

There are two provided implementations for snmp.security.usm.priv: one that depends on the pycryptodome library, and one that uses OpenSSL. The module initialization code will automatically select between these implementations, depending on whether these dependencies are installed.

pycryptodome

The standard snmp.security.usm.priv implementation uses pycryptodome to perform the encryption and decryption. pycryptodome will be installed automatically when you install snmp with pip. There is also a requirements.txt file provided in snmp/security/usm/priv/pycryptodome, which specifies the precise requirement.

OpenSSL

The other snmp.security.usm.priv implementation uses the EVP_* family of functions, from OpenSSL. To enable it, you will use the cffi library to generate and compile a Python module that can interface with OpenSSL. If present, this module will always take precedence over pycryptodome, based on the assumption that you would not take the time to install it unless you wanted to use it.

First, install the cffi library with this command:

pip install -r snmp/cffi/requirements.txt

After installing cffi, run the following commands in the Python interactive shell:

>>> from snmp.cffi.openssl import ffi
>>> ffi.compile()

If this command fails, the most likely cause is from missing OpenSSL headers. Most Linux distributions provide OpenSSL binaries automatically, but require you to install the headers separately. The precise instructions will vary by system, so it will be up to you to figure it out.

In Ubuntu, it’s as simple as

sudo apt install libssl-dev

You can also download and install OpenSSL from source quite easily (run Configure, and then make install). If you install in a non-standard location, then set CPPFLAGS="-isystem <prefix>/include" and LDFLAGS="-Wl,-rpath,<prefix>/lib" in your environment before opening the Python interactive shell.

If installing OpenSSL headers doesn’t fix your issue, or you get stuck, please file a GitHub issue or email me directly at charlescdtolley@protonmail.com.