tls_proxy_scan.c

[詳解]

/*++
/* NAME
/*  tls_proxy_scan
/* SUMMARY
/*  read TLS session state from stream
/* SYNOPSIS
/*  #include <tls_proxy.h>
/*
/*  int     tls_proxy_context_scan(scan_fn, stream, flags, ptr)
/*  ATTR_SCAN_MASTER_FN scan_fn;
/*  VSTREAM *stream;
/*  int     flags;
/*  void    *ptr;
/* DESCRIPTION
/*  tls_proxy_context_scan() reads a TLS_SESS_STATE structure
/*  from the named stream using the specified attribute scan
/*  routine.  tls_proxy_context_scan() is meant to be passed as
/*  a call-back to attr_scan(), thusly:
/*
/*  ... RECV_ATTR_FUNC(tls_proxy_context_scan, (void *) tls_context), ...
/* DIAGNOSTICS
/*  Fatal: out of memory.
/* LICENSE
/* .ad
/* .fi
/*  The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/*  Wietse Venema
/*  IBM T.J. Watson Research
/*  P.O. Box 704
/*  Yorktown Heights, NY 10598, USA
/*--*/

#ifdef USE_TLS

/* System library. */

#include <sys_defs.h>

/* Utility library */

#include <attr.h>

/* Global library. */

#include <mail_proto.h>

/* TLS library. */

#include <tls.h>
#include <tls_proxy.h>

/* tls_proxy_context_scan - receive TLS session state from stream */

int     tls_proxy_context_scan(ATTR_SCAN_MASTER_FN scan_fn, VSTREAM *fp,
                           int flags, void *ptr)
{
    TLS_SESS_STATE *tls_context = (TLS_SESS_STATE *) ptr;
    int     ret;
    VSTRING *peer_CN = vstring_alloc(25);
    VSTRING *issuer_CN = vstring_alloc(25);
    VSTRING *peer_cert_fprint = vstring_alloc(60);  /* 60 for SHA-1 */
    VSTRING *peer_pkey_fprint = vstring_alloc(60);  /* 60 for SHA-1 */
    VSTRING *protocol = vstring_alloc(25);
    VSTRING *cipher_name = vstring_alloc(25);

    /*
     * Note: memset() is not a portable way to initialize non-integer types.
     */
    memset(ptr, 0, sizeof(TLS_SESS_STATE));
    ret = scan_fn(fp, flags | ATTR_FLAG_MORE,
          RECV_ATTR_STR(MAIL_ATTR_PEER_CN, peer_CN),
          RECV_ATTR_STR(MAIL_ATTR_ISSUER_CN, issuer_CN),
          RECV_ATTR_STR(MAIL_ATTR_PEER_CERT_FPT, peer_cert_fprint),
          RECV_ATTR_STR(MAIL_ATTR_PEER_PKEY_FPT, peer_pkey_fprint),
          RECV_ATTR_INT(MAIL_ATTR_PEER_STATUS,
                &tls_context->peer_status),
          RECV_ATTR_STR(MAIL_ATTR_CIPHER_PROTOCOL, protocol),
          RECV_ATTR_STR(MAIL_ATTR_CIPHER_NAME, cipher_name),
          RECV_ATTR_INT(MAIL_ATTR_CIPHER_USEBITS,
                &tls_context->cipher_usebits),
          RECV_ATTR_INT(MAIL_ATTR_CIPHER_ALGBITS,
                &tls_context->cipher_algbits),
          ATTR_TYPE_END);
    tls_context->peer_CN = vstring_export(peer_CN);
    tls_context->issuer_CN = vstring_export(issuer_CN);
    tls_context->peer_cert_fprint = vstring_export(peer_cert_fprint);
    tls_context->peer_pkey_fprint = vstring_export(peer_pkey_fprint);
    tls_context->protocol = vstring_export(protocol);
    tls_context->cipher_name = vstring_export(cipher_name);
    return (ret == 9 ? 1 : -1);
}

#endif