static SPF_errcode_t
SPF_i_set_header_comment(SPF_response_t *spf_response)
{
SPF_server_t *spf_server;
SPF_request_t *spf_request;
char *spf_source;
size_t len;
char ip4_buf[ INET_ADDRSTRLEN ];
char ip6_buf[ INET6_ADDRSTRLEN ];
const char *ip;
char *buf;
char *sender_dom;
char *p, *p_end;
SPF_ASSERT_NOTNULL(spf_response);
spf_request = spf_response->spf_request;
SPF_ASSERT_NOTNULL(spf_request);
spf_server = spf_request->spf_server;
SPF_ASSERT_NOTNULL(spf_server);
if (spf_response->header_comment)
free(spf_response->header_comment);
spf_response->header_comment = NULL;
/* Is this cur_dom? */
sender_dom = spf_request->env_from_dp;
if (sender_dom == NULL)
sender_dom = spf_request->helo_dom;
if ( spf_response->reason == SPF_REASON_LOCAL_POLICY ) {
spf_source = strdup( "local policy" );
}
else if ( spf_response->reason == SPF_REASON_2MX ) {
if ( spf_request->rcpt_to_dom == NULL || spf_request->rcpt_to_dom[0] == '\0' )
SPF_error( "RCPT TO domain is NULL" );
spf_source = strdup( spf_request->rcpt_to_dom );
}
else if ( sender_dom == NULL ) {
spf_source = strdup( "unknown domain" );
}
else {
len = strlen( sender_dom ) + sizeof( "domain of " );
spf_source = malloc( len );
if ( spf_source )
snprintf( spf_source, len, "domain of %s", sender_dom );
}
if ( spf_source == NULL )
return SPF_E_INTERNAL_ERROR;
ip = NULL;
if ( spf_request->client_ver == AF_INET ) {
ip = inet_ntop( AF_INET, &spf_request->ipv4,
ip4_buf, sizeof( ip4_buf ) );
}
else if (spf_request->client_ver == AF_INET6 ) {
ip = inet_ntop( AF_INET6, &spf_request->ipv6,
ip6_buf, sizeof( ip6_buf ) );
}
if ( ip == NULL )
ip = "(unknown ip address)";
len = strlen( SPF_request_get_rec_dom(spf_request) ) + strlen( spf_source ) + strlen( ip ) + 80;
buf = malloc( len );
if ( buf == NULL ) {
free( spf_source );
return SPF_E_INTERNAL_ERROR;
}
p = buf;
p_end = p + len;
/* create the stock header comment */
p += snprintf( p, p_end - p, "%s: ", SPF_request_get_rec_dom(spf_request) );
switch(spf_response->result)
{
case SPF_RESULT_PASS:
if ( spf_response->reason == SPF_REASON_LOCALHOST )
snprintf( p, p_end - p, "localhost is always allowed." );
else if ( spf_response->reason == SPF_REASON_2MX )
snprintf( p, p_end - p, "message received from %s which is an MX secondary for %s.",
ip, spf_source );
else
snprintf( p, p_end - p, "%s designates %s as permitted sender",
spf_source, ip );
break;
case SPF_RESULT_FAIL:
snprintf( p, p_end - p, "%s does not designate %s as permitted sender",
spf_source, ip );
break;
case SPF_RESULT_SOFTFAIL:
snprintf( p, p_end - p, "transitioning %s does not designate %s as permitted sender",
spf_source, ip );
break;
case SPF_RESULT_PERMERROR:
snprintf(p, p_end - p, "error in processing during lookup of %s: %s",
spf_source, SPF_strerror(spf_response->err));
break;
case SPF_RESULT_NEUTRAL:
snprintf(p, p_end - p, "%s is neither permitted nor denied by %s",
ip, spf_source);
break;
case SPF_RESULT_NONE:
snprintf(p, p_end - p, "%s does not provide an SPF record",
spf_source);
break;
case SPF_RESULT_TEMPERROR:
snprintf(p, p_end - p, "encountered temporary error during SPF processing of %s",
spf_source );
break;
default:
snprintf( p, p_end - p, "error: unknown SPF result %d encountered while checking %s for %s",
spf_response->result, ip, spf_source );
break;
}
if (spf_source)
free(spf_source);
spf_response->header_comment = SPF_sanitize(spf_server, buf);
return SPF_E_SUCCESS;
}
/**
* This could better collect errors, like the compiler does.
* This requires that *bufp be either malloced to *buflenp, or NULL
* This may realloc *bufp.
*/
SPF_errcode_t
SPF_record_expand_data(SPF_server_t *spf_server,
SPF_request_t *spf_request,
SPF_response_t *spf_response,
SPF_data_t *data, size_t data_len,
char **bufp, size_t *buflenp)
{
SPF_data_t *d, *data_end;
size_t len;
const char *p_err; // XXX Check this value, when returned.
char *p, *p_end;
const char *p_read;
const char *p_read_end;
char *p_write;
char *p2, *p2_end;
const char *var;
char *munged_var = NULL;
char *url_var = NULL;
/* Pretty-printing buffers. */
char ip4_buf[ INET_ADDRSTRLEN ];
char ip6_buf[ INET6_ADDRSTRLEN ];
/* Hex buffer for ipv6 (size in nibbles) */
char ip6_rbuf[ sizeof( struct in6_addr ) * 4 + 1 ];
char time_buf[ sizeof( "4294967296" ) ]; /* 2^32 seconds max */
int num_found;
int i;
size_t buflen;
int compute_length;
SPF_errcode_t err;
/*
* make sure we were passed valid data to work with
*/
SPF_ASSERT_NOTNULL(spf_server);
SPF_ASSERT_NOTNULL(data);
SPF_ASSERT_NOTNULL(bufp);
SPF_ASSERT_NOTNULL(buflenp);
buflen = 1; /* For the terminating '\0' */
compute_length = 1;
p = NULL;
p_end = NULL;
/* data_end = SPF_mech_end_data( mech ); */ /* doesn't work for mods */
data_end = (SPF_data_t *)((char *)data + data_len);
top:
#ifdef DEBUG
fprintf(stderr, "Pass start compute_length=%d\n", compute_length);
#endif
/*
* expand the data
*/
for (d = data; d < data_end; d = SPF_data_next(d)) {
#ifdef DEBUG
fprintf(stderr, " Item type=%d at %p\n", d->dc.parm_type, d);
#endif
if (d->dc.parm_type == PARM_CIDR)
continue;
if (d->ds.parm_type == PARM_STRING) {
if (compute_length) {
buflen += d->ds.len;
continue;
}
/* This should NEVER happen now. */
if (p_end - (p + d->ds.len) <= 0)
SPF_error("Failed to allocate enough memory "
"to expand string.");
memcpy(p, SPF_data_str(d), d->ds.len);
p += d->ds.len;
continue;
}
/* Otherwise, it's a variable. */
var = NULL;
switch (d->dv.parm_type) {
case PARM_LP_FROM: /* local-part of envelope-sender */
var = spf_request->env_from_lp;
break;
case PARM_ENV_FROM: /* envelope-sender */
var = spf_request->env_from;
break;
case PARM_DP_FROM: /* envelope-domain */
var = spf_request->env_from_dp;
break;
case PARM_CUR_DOM: /* current-domain */
var = spf_request->cur_dom;
break;
case PARM_CLIENT_IP: /* SMTP client IP */
if (compute_length) {
len = sizeof(ip6_buf);
if (d->dv.url_encode)
len *= 3;
buflen += len;
continue;
}
if (spf_request->client_ver == AF_INET) {
p_err = inet_ntop(AF_INET, &spf_request->ipv4,
ip4_buf, sizeof(ip4_buf));
var = ip4_buf;
}
else if (spf_request->client_ver == AF_INET6) {
p2 = ip6_rbuf;
p2_end = p2 + sizeof(ip6_rbuf);
for (i = 0; i < array_elem(spf_request->ipv6.s6_addr); i++) {
p2 += snprintf(p2, p2_end - p2, "%.1x.%.1x.",
spf_request->ipv6.s6_addr[i] >> 4,
spf_request->ipv6.s6_addr[i] & 0xf);
}
/* squash the final '.' */
ip6_rbuf[sizeof(struct in6_addr) * 4 - 1] = '\0';
var = ip6_rbuf;
}
break;
case PARM_CLIENT_IP_P: /* SMTP client IP (pretty) */
if (compute_length) {
len = sizeof(ip6_buf);
if (d->dv.url_encode)
len *= 3;
buflen += len;
continue;
}
if (spf_request->client_ver == AF_INET) {
p_err = inet_ntop(AF_INET, &spf_request->ipv4,
ip4_buf, sizeof(ip4_buf));
var = ip4_buf;
}
else if (spf_request->client_ver == AF_INET6) {
p_err = inet_ntop(AF_INET6, &spf_request->ipv6,
ip6_buf, sizeof(ip6_buf));
var = ip6_buf;
}
break;
case PARM_TIME: /* time in UTC epoch secs */
if (compute_length) {
len = sizeof(time_buf);
/* This never gets bigger using URL encoding. */
buflen += len;
continue;
}
snprintf(time_buf, sizeof(time_buf), "%ld",
(long)time(NULL));
var = time_buf;
break;
case PARM_CLIENT_DOM: /* SMTP client domain name */
var = SPF_request_get_client_dom(spf_request);
if (! var)
return SPF_E_NO_MEMORY;
break;
case PARM_CLIENT_VER: /* IP ver str - in-addr/ip6 */
if (spf_request->client_ver == AF_INET)
var = client_ver_ipv4;
else if (spf_request->client_ver == AF_INET6)
var = client_ver_ipv6;
break;
case PARM_HELO_DOM: /* HELO/EHLO domain */
var = spf_request->helo_dom;
break;
case PARM_REC_DOM: /* receiving domain */
var = SPF_request_get_rec_dom(spf_request);
break;
default:
#ifdef DEBUG
fprintf(stderr, "Invalid variable %d\n", d->dv.parm_type);
#endif
return SPF_E_INVALID_VAR;
break;
}
if (var == NULL)
return SPF_E_UNINIT_VAR;
len = strlen(var);
if (compute_length) {
if (d->dv.url_encode)
len *= 3;
buflen += len;
continue;
}
/* Now we put 'var' through the munging procedure. */
munged_var = (char *)malloc(len + 1);
if (munged_var == NULL)
return SPF_E_NO_MEMORY;
memset(munged_var, 0, len + 1);
p_read_end = var + len;
p_write = munged_var;
/* reverse */
/* The following code confuses both me and Coverity. Shevek. */
if (d->dv.rev) {
p_read = p_read_end - 1;
while ( p_read >= var ) {
if ( SPF_delim_valid(d, *p_read) ) {
/* Subtract 1 because p_read points to delim, and
* p_read_end points to the following delim. */
len = p_read_end - p_read - 1;
memcpy( p_write, p_read + 1, len );
p_write += len;
*p_write++ = '.';
p_read_end = p_read;
}
p_read--;
}
/* Now p_read_end should point one before the start of the
* string. p_read_end might also point there if the string
* starts with a delimiter. */
if (p_read_end >= p_read) {
len = p_read_end - p_read - 1;
memcpy( p_write, p_read + 1, len );
p_write += len;
*p_write++ = '.';
}
/* p_write always points to the 'next' character. */
p_write--;
*p_write = '\0';
}
else {
p_read = var;
while (p_read < p_read_end) {
if (SPF_delim_valid(d, *p_read))
*p_write++ = '.';
else
*p_write++ = *p_read;
p_read++;
}
*p_write = '\0';
}
/* Now munged_var is a copy of var, possibly reversed, and
* thus len == strlen(munged_var). However, we continue to
* manipulate the underlying munged_var since var is const. */
/* truncate, from the right hand side. */
if (d->dv.num_rhs > 0) {
p_read_end = munged_var + len; /* const, at '\0' */
p_write = munged_var + len - 1;
num_found = 0;
while (p_write > munged_var) {
if (*p_write == '.')
num_found++;
if (num_found == d->dv.num_rhs)
break;
p_write--;
}
p_write++; /* Move to just after the '.' */
/* This moves the '\0' as well. */
len = p_read_end - p_write;
memmove(munged_var, p_write, len + 1);
}
var = munged_var;
/* Now, we have 'var', of length 'len' */
/* URL encode */
if (d->dv.url_encode) {
url_var = malloc(len * 3 + 1);
if (url_var == NULL) {
if (munged_var)
free(munged_var);
return SPF_E_NO_MEMORY;
}
p_read = var;
p_write = url_var;
/* escape non-uric characters (rfc2396) */
while ( *p_read != '\0' )
{
if ( isalnum( (unsigned char)( *p_read ) ) )
*p_write++ = *p_read++;
else
{
switch( *p_read )
{
case '-':
case '_':
case '.':
case '!':
case '~':
case '*':
case '\'':
case '(':
case ')':
*p_write++ = *p_read++;
break;
default:
/* No point doing snprintf with a const '4'
* because we know we're going to get 4
* characters anyway. */
sprintf( p_write, "%%%02x", *p_read );
p_write += 3;
p_read++;
break;
}
}
}
*p_write = '\0';
var = url_var;
len = p_write - url_var; /* Not actually used. */
}
/* finish up */
len = snprintf(p, p_end - p, "%s", var);
p += len;
if (p_end - p <= 0) {
if (munged_var)
free(munged_var);
if (url_var)
free(url_var);
return SPF_E_INTERNAL_ERROR;
}
if (munged_var)
free(munged_var);
munged_var = NULL;
if (url_var)
free(url_var);
url_var = NULL;
}
static int verify_data(spctx_t* ctx)
{
char ebuf[256];
int n;
SPF_request_t *spf_request = NULL;
char * xforwardaddr = NULL;
char * xforwardhelo = NULL;
if(spf_server == NULL)
{
/* redirect errors */
SPF_error_handler = SPF_error_syslog;
SPF_warning_handler = SPF_warning_syslog;
SPF_info_handler = SPF_info_syslog;
SPF_debug_handler = SPF_debug_syslog;
spf_server = SPF_server_new(SPF_DNS_CACHE, 1);
if (spf_server == NULL)
return -1;
}
/* trim string */
if(ctx->xforwardaddr)
xforwardaddr = trim_space(ctx->xforwardaddr);
if(ctx->xforwardhelo)
xforwardhelo = trim_space(ctx->xforwardhelo);
sp_messagex(ctx, LOG_DEBUG, "New connection: ADDR %s - MAIL FROM %s - XF-ADDR %s - XF-HELO %s",
ctx->client.peername, ctx->sender, xforwardaddr, xforwardhelo);
spf_request = SPF_request_new(spf_server);
if( xforwardaddr )
SPF_request_set_ipv4_str( spf_request, xforwardaddr );
else if ( ctx->client.peername )
SPF_request_set_ipv4_str( spf_request, ctx->client.peername );
if( xforwardhelo )
SPF_request_set_helo_dom( spf_request, xforwardhelo );
if( ctx->sender )
SPF_request_set_env_from( spf_request, ctx->sender );
SPF_response_t *spf_response = NULL;
SPF_request_query_mailfrom(spf_request, &spf_response);
char hostname[100];
strncpy(hostname, SPF_request_get_rec_dom(spf_request), 99);
char *result_spf = NULL;
switch(SPF_response_result(spf_response))
{
case SPF_RESULT_NONE:
sp_messagex(ctx, LOG_DEBUG, "No SPF policy found for %s", ctx->sender);
result_spf = "none";
break;
case SPF_RESULT_NEUTRAL:
result_spf = "neutral";
sp_messagex(ctx, LOG_DEBUG, "SPF: NEUTRAL for %s", ctx->sender);
break;
case SPF_RESULT_SOFTFAIL:
result_spf = "softfail";
sp_messagex(ctx, LOG_DEBUG, "SPF: SOFTFAIL for %s", ctx->sender);
break;
case SPF_RESULT_PASS:
result_spf = "pass";
sp_messagex(ctx, LOG_DEBUG, "SPF: PASS for %s", ctx->sender);
break;
case SPF_RESULT_FAIL:
buffer_reject_message("550 SPF Reject", ebuf, sizeof(ebuf));
buffer_reject_message(SPF_response_get_smtp_comment(spf_response), ebuf, sizeof(ebuf));
final_reject_message(ebuf, sizeof(ebuf));
sp_messagex(ctx, LOG_DEBUG, "SPF FAIL for %s, ignore message", ctx->sender);
SPF_response_free(spf_response);
SPF_request_free(spf_request);
if(sp_fail_data(ctx, ebuf) == -1)
return -1;
else
return 0;
break;
case SPF_RESULT_TEMPERROR:
case SPF_RESULT_PERMERROR:
case SPF_RESULT_INVALID:
buffer_reject_message("450 temporary failure", ebuf, sizeof(ebuf));
final_reject_message(ebuf, sizeof(ebuf));
sp_messagex(ctx, LOG_DEBUG, "TEMP ERROR or INVALID RECORD in SPF for %s", ctx->sender);
SPF_response_free(spf_response);
SPF_request_free(spf_request);
if(sp_fail_data(ctx, ebuf) == -1)
return -1;
else
return 0;
break;
};
char auth_result_spf[1025];
snprintf(auth_result_spf, 1024, "spf=%s smtp.mailfrom=%s", result_spf, ctx->sender);
SPF_response_free(spf_response);
SPF_request_free(spf_request);
/* Tell client to start sending data */
if(sp_start_data (ctx) < 0)
return -1; /* Message already printed */
/* Setup DKIM verifier */
DKIMContext ctxt;
DKIMVerifyOptions vopts = {0};
vopts.nCheckPractices = 1;
vopts.pfnSelectorCallback = NULL; //SelectorCallback;
n = DKIMVerifyInit( &ctxt, &vopts );
/* Read data into verifier */
int len = -1;
const char *buffer = 0;
do
{
len = sp_read_data(ctx, &buffer);
if(len == -1)
return -1;
if(len > 0)
{
DKIMVerifyProcess( &ctxt, buffer, len );
sp_write_data( ctx, buffer, len );
}
} while(len > 0);
sp_write_data( ctx, NULL, 0 );
/* Verify DKIM */
n = DKIMVerifyResults( &ctxt );
/* Get verification details */
int nSigCount = 0;
DKIMVerifyDetails* pDetails;
char szPolicy[512];
DKIMVerifyGetDetails(&ctxt, &nSigCount, &pDetails, szPolicy );
/* Proxy based on verification results */
char auth_result_dkim[1025];
if(nSigCount == 0)
{
sp_messagex(ctx, LOG_DEBUG, "No DKIM signature, passthrough");
snprintf(auth_result_dkim, 1024, "dkim=none");
}
else if (n == DKIM_SUCCESS || n == DKIM_PARTIAL_SUCCESS)
{
sp_messagex(ctx, LOG_DEBUG, "DKIM verification: Success, adding header information");
int strpos = 0;
int i=0;
for(; i<nSigCount; ++i)
{
snprintf(&auth_result_dkim[strpos], 1024 - strpos,
"%sdkim=%s header.d=%s", (i>0 ? ";\n" : ""),
(pDetails[i].nResult == DKIM_SUCCESS ? "pass" : "fail"),
pDetails[i].szSignatureDomain);
strpos = strlen(auth_result_dkim);
}
} else {
sp_messagex(ctx, LOG_DEBUG, "DKIM verification: Failed, report error and ignore message.");
buffer_reject_message("550 DKIM Signature failed verification (http://www.dkim.org/info/dkim-faq.html)", ebuf, sizeof(ebuf));
final_reject_message(ebuf, sizeof(ebuf));
DKIMVerifyFree( &ctxt );
if(sp_fail_data(ctx, ebuf) == -1)
return -1;
else
return 0;
}
DKIMVerifyFree( &ctxt );
char auth_results_header[1025];
snprintf(auth_results_header, 1024, "Authentication-Results: %s;\n %s;\n %s;",
hostname, auth_result_spf, auth_result_dkim);
if( sp_done_data(ctx, auth_results_header) == -1)
return -1;
return 0;
}