sslsniff(8)

NAME
sslsniff - Print data passed to OpenSSL, GnuTLS or NSS. Uses Linux eBPF/bcc.

SYNOPSIS
sslsniff [-h] [-p PID] [-u UID] [-x] [-c COMM] [-o] [-g] [-n] [-d] [--hexdump] [--max-buffer-size SIZE] [-l] [--handshake] [--extra-lib EXTRA_LIB]

DESCRIPTION
sslsniff prints data sent to write/send and read/recv functions of OpenSSL, GnuTLS and NSS, allowing us to read plain text content before encryption (when writing) and after decryption (when reading).

This works reading the second parameter of both functions (*buf).

Since this uses BPF, only the root user can use this tool.

REQUIREMENTS
CONFIG_BPF and bcc.

OPTIONS

-h  Print usage message.

-p PID
    Trace only functions in this process PID.

-u UID
    Trace only calls made by this UID.

-x  Show extra fields: UID and TID.

-c COMM
    Show only processes that match this COMM exactly.

-o, --no-openssl
    Do not trace OpenSSL functions.

-g, --no-gnutls
    Do not trace GnuTLS functions.

-n, --no-nss
    Do not trace GnuTLS functions.

--hexdump
    Show data as hexdump instead of trying to decode it as UTF-8

--max-buffer-size SIZE
    Sets maximum buffer size of intercepted data. Longer values would be truncated. Default value is 8 Kib, maximum possible value is a bit less than 32 Kib.

-l, --latency
    Show function latency in ms.

--handshake
    Show handshake latency, enabled only if latency option is on.

--extra-lib EXTRA_LIB
    Consist type of the library and library path separated by colon. Supported library types are: openssl, gnutls, nss. Can be specified multiple times.

EXAMPLES

Print all calls to SSL write/send and read/recv system-wide:
    # sslsniff

Print only OpenSSL calls issued by user with UID 1000
    # sslsniff -u 1000 --no-nss --no-gnutls

Print SSL handshake event and latency for all traced functions:
    # sslsniff -l --handshake

Print only calls to OpenSSL from /some/path/libssl.so
    sslsniff --no-openssl --no-gnutls --no-nss --extra-lib openssl:/some/path/libssl.so

FIELDS

FUNC
    Which function is being called (write/send or read/recv)

TIME
    Time of the command, in seconds.

COMM
    Entered command.

PID Process ID calling SSL.

LEN Bytes written or read by SSL functions.

UID UID of the process, displayed only if launched with -x.

TID Thread ID, displayed only if launched with -x.

LAT(ms)
    Function latency in ms.

SOURCE
This is from bcc.

    https://github.com/iovisor/bcc

Also look in the bcc distribution for a companion _examples.txt file containing example usage, output, and commentary for this tool.

OS
Linux

STABILITY
Unstable - in development.

AUTHORS
Adrian Lopez and Mark Drayton

SEE ALSO
trace(8)