#define PDKIM_MAX_HEADERS 512
#define PDKIM_MAX_BODY_LINE_LEN 16384
#define PDKIM_DNS_TXT_MAX_NAMELEN 1024
-#define PDKIM_DEFAULT_SIGN_HEADERS "From:Sender:Reply-To:Subject:Date:"\
- "Message-ID:To:Cc:MIME-Version:Content-Type:"\
- "Content-Transfer-Encoding:Content-ID:"\
- "Content-Description:Resent-Date:Resent-From:"\
- "Resent-Sender:Resent-To:Resent-Cc:"\
- "Resent-Message-ID:In-Reply-To:References:"\
- "List-Id:List-Help:List-Unsubscribe:"\
- "List-Subscribe:List-Post:List-Owner:List-Archive"
/* -------------------------------------------------------------------------- */
struct pdkim_stringlist {
/* Trim whitespace fore & aft */
static void
-pdkim_strtrim(uschar * str)
+pdkim_strtrim(gstring * str)
{
-uschar * p = str;
-uschar * q = str;
-while (*p == '\t' || *p == ' ') p++; /* skip whitespace */
-while (*p) {*q = *p; q++; p++;} /* dump the leading whitespace */
-*q = '\0';
-while (q != str && ( (*q == '\0') || (*q == '\t') || (*q == ' ') ) )
- { /* dump trailing whitespace */
- *q = '\0';
- q--;
- }
+uschar * p = str->s;
+uschar * q;
+
+while (*p == '\t' || *p == ' ') /* dump the leading whitespace */
+ { str->size--; str->ptr--; str->s++; }
+
+while ( str->ptr > 0
+ && (q = str->s + str->ptr - 1), *q == '\t' || *q == ' '
+ )
+ str->ptr--; /* dump trailing whitespace */
+
+(void) string_from_gstring(str);
}
/* -------------------------------------------------------------------------- */
/* Matches the name of the passed raw "header" against
the passed colon-separated "tick", and invalidates
- the entry in tick. Returns OK or fail-code */
-/*XXX might be safer done using a pdkim_stringlist for "tick" */
+ the entry in tick. Entries can be prefixed for multi- or over-signing,
+ in which case do not invalidate.
+
+ Returns OK for a match, or fail-code
+*/
static int
header_name_match(const uschar * header, uschar * tick)
{
-uschar * hname;
-uschar * lcopy;
-uschar * p;
-uschar * q;
+const uschar * ticklist = tick;
+int sep = ':';
+BOOL multisign;
+uschar * hname, * p, * ele;
uschar * hcolon = Ustrchr(header, ':'); /* Get header name */
if (!hcolon)
/* if we had strncmpic() we wouldn't need this copy */
hname = string_copyn(header, hcolon-header);
-/* Copy tick-off list locally, so we can punch zeroes into it */
-p = lcopy = string_copy(tick);
-
-for (q = Ustrchr(p, ':'); q; q = Ustrchr(p, ':'))
+while (p = US ticklist, ele = string_nextinlist(&ticklist, &sep, NULL, 0))
{
- *q = '\0';
- if (strcmpic(p, hname) == 0)
- goto found;
-
- p = q+1;
+ switch (*ele)
+ {
+ case '=': case '+': multisign = TRUE; ele++; break;
+ default: multisign = FALSE; break;
}
-if (strcmpic(p, hname) == 0)
- goto found;
-
+ if (strcmpic(ele, hname) == 0)
+ {
+ if (!multisign)
+ *p = '_'; /* Invalidate this header name instance in tick-off list */
+ return PDKIM_OK;
+ }
+ }
return PDKIM_FAIL;
-
-found:
- /* Invalidate header name instance in tick-off list */
- tick[p-lcopy] = '_';
- return PDKIM_OK;
}
{
pdkim_signature * sig;
uschar *p, *q;
-uschar * cur_tag = NULL; int ts = 0, tl = 0;
-uschar * cur_val = NULL; int vs = 0, vl = 0;
+gstring * cur_tag = NULL;
+gstring * cur_val = NULL;
BOOL past_hname = FALSE;
BOOL in_b_val = FALSE;
int where = PDKIM_HDR_LIMBO;
if (where == PDKIM_HDR_TAG)
{
if (c >= 'a' && c <= 'z')
- cur_tag = string_catn(cur_tag, &ts, &tl, p, 1);
+ cur_tag = string_catn(cur_tag, p, 1);
if (c == '=')
{
- cur_tag[tl] = '\0';
- if (Ustrcmp(cur_tag, "b") == 0)
+ if (Ustrcmp(string_from_gstring(cur_tag), "b") == 0)
{
*q++ = '=';
in_b_val = TRUE;
if (c == ';' || c == '\0')
{
- if (tl && vl)
+ if (cur_tag && cur_val)
{
- cur_val[vl] = '\0';
+ (void) string_from_gstring(cur_val);
pdkim_strtrim(cur_val);
- DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag, cur_val);
+ DEBUG(D_acl) debug_printf(" %s=%s\n", cur_tag->s, cur_val->s);
- switch (*cur_tag)
+ switch (*cur_tag->s)
{
case 'b':
- pdkim_decode_base64(cur_val,
- cur_tag[1] == 'h' ? &sig->bodyhash : &sig->sighash);
+ pdkim_decode_base64(cur_val->s,
+ cur_tag->s[1] == 'h' ? &sig->bodyhash : &sig->sighash);
break;
case 'v':
/* We only support version 1, and that is currently the
only version there is. */
sig->version =
- Ustrcmp(cur_val, PDKIM_SIGNATURE_VERSION) == 0 ? 1 : -1;
+ Ustrcmp(cur_val->s, PDKIM_SIGNATURE_VERSION) == 0 ? 1 : -1;
break;
case 'a':
{
- uschar * s = Ustrchr(cur_val, '-');
+ uschar * s = Ustrchr(cur_val->s, '-');
for(i = 0; i < nelem(pdkim_keytypes); i++)
- if (Ustrncmp(cur_val, pdkim_keytypes[i], s - cur_val) == 0)
+ if (Ustrncmp(cur_val->s, pdkim_keytypes[i], s - cur_val->s) == 0)
{ sig->keytype = i; break; }
for (++s, i = 0; i < nelem(pdkim_hashes); i++)
if (Ustrcmp(s, pdkim_hashes[i].dkim_hashname) == 0)
case 'c':
for (i = 0; pdkim_combined_canons[i].str; i++)
- if (Ustrcmp(cur_val, pdkim_combined_canons[i].str) == 0)
+ if (Ustrcmp(cur_val->s, pdkim_combined_canons[i].str) == 0)
{
sig->canon_headers = pdkim_combined_canons[i].canon_headers;
sig->canon_body = pdkim_combined_canons[i].canon_body;
break;
case 'q':
for (i = 0; pdkim_querymethods[i]; i++)
- if (Ustrcmp(cur_val, pdkim_querymethods[i]) == 0)
+ if (Ustrcmp(cur_val->s, pdkim_querymethods[i]) == 0)
{
sig->querymethod = i;
break;
}
break;
case 's':
- sig->selector = string_copy(cur_val); break;
+ sig->selector = string_copyn(cur_val->s, cur_val->ptr); break;
case 'd':
- sig->domain = string_copy(cur_val); break;
+ sig->domain = string_copyn(cur_val->s, cur_val->ptr); break;
case 'i':
- sig->identity = pdkim_decode_qp(cur_val); break;
+ sig->identity = pdkim_decode_qp(cur_val->s); break;
case 't':
- sig->created = strtoul(CS cur_val, NULL, 10); break;
+ sig->created = strtoul(CS cur_val->s, NULL, 10); break;
case 'x':
- sig->expires = strtoul(CS cur_val, NULL, 10); break;
+ sig->expires = strtoul(CS cur_val->s, NULL, 10); break;
case 'l':
- sig->bodylength = strtol(CS cur_val, NULL, 10); break;
+ sig->bodylength = strtol(CS cur_val->s, NULL, 10); break;
case 'h':
- sig->headernames = string_copy(cur_val); break;
+ sig->headernames = string_copyn(cur_val->s, cur_val->ptr); break;
case 'z':
- sig->copiedheaders = pdkim_decode_qp(cur_val); break;
+ sig->copiedheaders = pdkim_decode_qp(cur_val->s); break;
default:
DEBUG(D_acl) debug_printf(" Unknown tag encountered\n");
break;
}
}
- tl = 0;
- vl = 0;
+ cur_tag = cur_val = NULL;
in_b_val = FALSE;
where = PDKIM_HDR_LIMBO;
}
else
- cur_val = string_catn(cur_val, &vs, &vl, p, 1);
+ cur_val = string_catn(cur_val, p, 1);
}
NEXT_CHAR:
pdkim_signature * sig, * last_sig;
/* Special case: The last header can have an extra \r appended */
-if ( (ctx->cur_header_len > 1) &&
- (ctx->cur_header[(ctx->cur_header_len)-1] == '\r') )
- --ctx->cur_header_len;
-ctx->cur_header[ctx->cur_header_len] = '\0';
+if ( (ctx->cur_header->ptr > 1) &&
+ (ctx->cur_header->s[ctx->cur_header->ptr-1] == '\r') )
+ --ctx->cur_header->ptr;
+(void) string_from_gstring(ctx->cur_header);
if (++ctx->num_headers > PDKIM_MAX_HEADERS) goto BAIL;
for (sig = ctx->sig; sig; sig = sig->next) /* Traverse all signatures */
/* Add header to the signed headers list (in reverse order) */
- sig->headers = pdkim_prepend_stringlist(sig->headers,
- ctx->cur_header);
+ sig->headers = pdkim_prepend_stringlist(sig->headers, ctx->cur_header->s);
/* VERIFICATION ----------------------------------------------------------- */
/* DKIM-Signature: headers are added to the verification list */
DEBUG(D_acl)
{
debug_printf("PDKIM >> raw hdr: ");
- pdkim_quoteprint(CUS ctx->cur_header, ctx->cur_header_len);
+ pdkim_quoteprint(CUS ctx->cur_header->s, ctx->cur_header->ptr);
}
#endif
- if (strncasecmp(CCS ctx->cur_header,
+ if (strncasecmp(CCS ctx->cur_header->s,
DKIM_SIGNATURE_HEADERNAME,
Ustrlen(DKIM_SIGNATURE_HEADERNAME)) == 0)
{
DEBUG(D_acl) debug_printf(
"PDKIM >> Found sig, trying to parse >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
- sig = pdkim_parse_sig_header(ctx, ctx->cur_header);
+ sig = pdkim_parse_sig_header(ctx, ctx->cur_header->s);
if (!(last_sig = ctx->sig))
ctx->sig = sig;
}
/* all headers are stored for signature verification */
- ctx->headers = pdkim_prepend_stringlist(ctx->headers, ctx->cur_header);
+ ctx->headers = pdkim_prepend_stringlist(ctx->headers, ctx->cur_header->s);
}
BAIL:
-ctx->cur_header[ctx->cur_header_len = 0] = '\0'; /* leave buffer for reuse */
+ctx->cur_header->s[ctx->cur_header->ptr = 0] = '\0'; /* leave buffer for reuse */
return PDKIM_OK;
}
else if (c == '\n')
{
if (!(ctx->flags & PDKIM_SEEN_CR)) /* emulate the CR */
- ctx->cur_header = string_catn(ctx->cur_header, &ctx->cur_header_size,
- &ctx->cur_header_len, CUS "\r", 1);
+ ctx->cur_header = string_catn(ctx->cur_header, CUS "\r", 1);
if (ctx->flags & PDKIM_SEEN_LF) /* Seen last header line */
{
ctx->flags &= ~PDKIM_SEEN_LF;
}
- if (ctx->cur_header_len < PDKIM_MAX_HEADER_LEN)
- ctx->cur_header = string_catn(ctx->cur_header, &ctx->cur_header_size,
- &ctx->cur_header_len, CUS &data[p], 1);
+ if (!ctx->cur_header || ctx->cur_header->ptr < PDKIM_MAX_HEADER_LEN)
+ ctx->cur_header = string_catn(ctx->cur_header, CUS &data[p], 1);
}
}
return PDKIM_OK;
-/* Extend a grwong header with a continuation-linebreak */
-static uschar *
-pdkim_hdr_cont(uschar * str, int * size, int * ptr, int * col)
+/* Extend a growing header with a continuation-linebreak */
+static gstring *
+pdkim_hdr_cont(gstring * str, int * col)
{
*col = 1;
-return string_catn(str, size, ptr, US"\r\n\t", 3);
+return string_catn(str, US"\r\n\t", 3);
}
*
* col: this int holds and receives column number (octets since last '\n')
* str: partial string to append to
- * size: current buffer size for str
- * ptr: current tail-pointer for str
* pad: padding, split line or space after before or after eg: ";"
* intro: - must join to payload eg "h=", usually the tag name
* payload: eg base64 data - long data can be split arbitrarily.
* names longer than 78, or bogus col. Input is assumed to be free of line breaks.
*/
-static uschar *
-pdkim_headcat(int * col, uschar * str, int * size, int * ptr,
+static gstring *
+pdkim_headcat(int * col, gstring * str,
const uschar * pad, const uschar * intro, const uschar * payload)
{
size_t l;
{
l = Ustrlen(pad);
if (*col + l > 78)
- str = pdkim_hdr_cont(str, size, ptr, col);
- str = string_catn(str, size, ptr, pad, l);
+ str = pdkim_hdr_cont(str, col);
+ str = string_catn(str, pad, l);
*col += l;
}
if (*col + l > 78)
{ /*can't fit intro - start a new line to make room.*/
- str = pdkim_hdr_cont(str, size, ptr, col);
+ str = pdkim_hdr_cont(str, col);
l = intro?Ustrlen(intro):0;
}
{ /* this fragment will not fit on a single line */
if (pad)
{
- str = string_catn(str, size, ptr, US" ", 1);
+ str = string_catn(str, US" ", 1);
*col += 1;
pad = NULL; /* only want this once */
l--;
{
size_t sl = Ustrlen(intro);
- str = string_catn(str, size, ptr, intro, sl);
+ str = string_catn(str, intro, sl);
*col += sl;
l -= sl;
intro = NULL; /* only want this once */
size_t sl = Ustrlen(payload);
size_t chomp = *col+sl < 77 ? sl : 78-*col;
- str = string_catn(str, size, ptr, payload, chomp);
+ str = string_catn(str, payload, chomp);
*col += chomp;
payload += chomp;
l -= chomp-1;
}
/* the while precondition tells us it didn't fit. */
- str = pdkim_hdr_cont(str, size, ptr, col);
+ str = pdkim_hdr_cont(str, col);
}
if (*col + l > 78)
{
- str = pdkim_hdr_cont(str, size, ptr, col);
+ str = pdkim_hdr_cont(str, col);
pad = NULL;
}
if (pad)
{
- str = string_catn(str, size, ptr, US" ", 1);
+ str = string_catn(str, US" ", 1);
*col += 1;
pad = NULL;
}
{
size_t sl = Ustrlen(intro);
- str = string_catn(str, size, ptr, intro, sl);
+ str = string_catn(str, intro, sl);
*col += sl;
l -= sl;
intro = NULL;
{
size_t sl = Ustrlen(payload);
- str = string_catn(str, size, ptr, payload, sl);
+ str = string_catn(str, payload, sl);
*col += sl;
}
uschar * base64_bh;
uschar * base64_b;
int col = 0;
-uschar * hdr; int hdr_size = 0, hdr_len = 0;
-uschar * canon_all; int can_size = 0, can_len = 0;
+gstring * hdr;
+gstring * canon_all;
-canon_all = string_cat (NULL, &can_size, &can_len,
- pdkim_canons[sig->canon_headers]);
-canon_all = string_catn(canon_all, &can_size, &can_len, US"/", 1);
-canon_all = string_cat (canon_all, &can_size, &can_len,
- pdkim_canons[sig->canon_body]);
-canon_all[can_len] = '\0';
+canon_all = string_cat (NULL, pdkim_canons[sig->canon_headers]);
+canon_all = string_catn(canon_all, US"/", 1);
+canon_all = string_cat (canon_all, pdkim_canons[sig->canon_body]);
+(void) string_from_gstring(canon_all);
-hdr = string_cat(NULL, &hdr_size, &hdr_len,
- US"DKIM-Signature: v="PDKIM_SIGNATURE_VERSION);
-col = hdr_len;
+hdr = string_cat(NULL, US"DKIM-Signature: v="PDKIM_SIGNATURE_VERSION);
+col = hdr->ptr;
/* Required and static bits */
-hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"a=",
- dkim_sig_to_a_tag(sig));
-hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"q=",
- pdkim_querymethods[sig->querymethod]);
-hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"c=",
- canon_all);
-hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"d=",
- sig->domain);
-hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"s=",
- sig->selector);
+hdr = pdkim_headcat(&col, hdr, US";", US"a=", dkim_sig_to_a_tag(sig));
+hdr = pdkim_headcat(&col, hdr, US";", US"q=", pdkim_querymethods[sig->querymethod]);
+hdr = pdkim_headcat(&col, hdr, US";", US"c=", canon_all->s);
+hdr = pdkim_headcat(&col, hdr, US";", US"d=", sig->domain);
+hdr = pdkim_headcat(&col, hdr, US";", US"s=", sig->selector);
/* list of header names can be split between items. */
{
if (c) *c ='\0';
if (!i)
- hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, NULL, NULL, US":");
+ hdr = pdkim_headcat(&col, hdr, NULL, NULL, US":");
- hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, s, i, n);
+ hdr = pdkim_headcat(&col, hdr, s, i, n);
if (!c)
break;
}
base64_bh = pdkim_encode_base64(&sig->bodyhash);
-hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"bh=", base64_bh);
+hdr = pdkim_headcat(&col, hdr, US";", US"bh=", base64_bh);
/* Optional bits */
if (sig->identity)
- hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"i=", sig->identity);
+ hdr = pdkim_headcat(&col, hdr, US";", US"i=", sig->identity);
if (sig->created > 0)
{
uschar minibuf[20];
snprintf(CS minibuf, sizeof(minibuf), "%lu", sig->created);
- hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"t=", minibuf);
+ hdr = pdkim_headcat(&col, hdr, US";", US"t=", minibuf);
}
if (sig->expires > 0)
uschar minibuf[20];
snprintf(CS minibuf, sizeof(minibuf), "%lu", sig->expires);
- hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"x=", minibuf);
+ hdr = pdkim_headcat(&col, hdr, US";", US"x=", minibuf);
}
if (sig->bodylength >= 0)
uschar minibuf[20];
snprintf(CS minibuf, sizeof(minibuf), "%lu", sig->bodylength);
- hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"l=", minibuf);
+ hdr = pdkim_headcat(&col, hdr, US";", US"l=", minibuf);
}
/* Preliminary or final version? */
if (final)
{
base64_b = pdkim_encode_base64(&sig->sighash);
- hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"b=", base64_b);
+ hdr = pdkim_headcat(&col, hdr, US";", US"b=", base64_b);
/* add trailing semicolon: I'm not sure if this is actually needed */
- hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, NULL, US";", US"");
+ hdr = pdkim_headcat(&col, hdr, NULL, US";", US"");
}
else
{
the headcat routine could insert a linebreak which the relaxer would reduce
to a single space preceding the terminating semicolon, resulting in an
incorrect header-hash. */
- hdr = pdkim_headcat(&col, hdr, &hdr_size, &hdr_len, US";", US"b=;", US"");
+ hdr = pdkim_headcat(&col, hdr, US";", US"b=;", US"");
}
-hdr[hdr_len] = '\0';
-return hdr;
+return string_from_gstring(hdr);
}
/* Check if we must still flush a (partial) header. If that is the
case, the message has no body, and we must compute a body hash
out of '<CR><LF>' */
-if (ctx->cur_header && ctx->cur_header_len)
+if (ctx->cur_header && ctx->cur_header->ptr > 0)
{
blob * rnl = NULL;
int rc;
hctx hhash_ctx;
uschar * sig_hdr = US"";
blob hhash;
- blob hdata;
- int hdata_alloc = 0;
-
- hdata.data = NULL;
- hdata.len = 0;
+ gstring * hdata = NULL;
if (!exim_sha_init(&hhash_ctx, pdkim_hashes[sig->hashtype].exim_hashmethod))
{
if (ctx->flags & PDKIM_MODE_SIGN)
{
- int hs = 0, hl = 0;
+ gstring * g = NULL;
pdkim_stringlist *p;
const uschar * l;
uschar * s;
if (header_name_match(rh, sig->sign_headers) == PDKIM_OK)
{
/* Collect header names (Note: colon presence is guaranteed here) */
- sig->headernames = string_append_listele_n(sig->headernames, &hs, &hl,
- ':', rh, Ustrchr(rh, ':') - rh);
+ g = string_append_listele_n(g, ':', rh, Ustrchr(rh, ':') - rh);
if (sig->canon_headers == PDKIM_CANON_RELAXED)
rh = pdkim_relax_header(rh, TRUE); /* cook header for relaxed canon */
exim_sha_update(&hhash_ctx, CUS rh, Ustrlen(rh));
/* Remember headers block for signing (when the library cannot do incremental) */
- (void) exim_dkim_data_append(&hdata, &hdata_alloc, rh);
+ hdata = exim_dkim_data_append(hdata, rh);
DEBUG(D_acl) pdkim_quoteprint(rh, Ustrlen(rh));
}
}
- /* Any headers we wanted to sign but were not present must also be listed */
+ /* Any headers we wanted to sign but were not present must also be listed.
+ Ignore elements that have been ticked-off or are marked as never-oversign. */
+
l = sig->sign_headers;
while((s = string_nextinlist(&l, &sep, NULL, 0)))
- if (*s != '_')
- sig->headernames = string_append_listele(sig->headernames, &hs, &hl, ':', s);
- sig->headernames[hl] = '\0';
+ {
+ if (*s == '+') /* skip oversigning marker */
+ s++;
+ if (*s != '_' && *s != '=')
+ g = string_append_listele(g, ':', s);
+ }
+ sig->headernames = string_from_gstring(g);
/* Create signature header with b= omitted */
sig_hdr = pdkim_create_header(sig, FALSE);
/* Remember headers block for signing (when the signing library cannot do
incremental) */
if (ctx->flags & PDKIM_MODE_SIGN)
- (void) exim_dkim_data_append(&hdata, &hdata_alloc, US sig_hdr);
+ hdata = exim_dkim_data_append(hdata, US sig_hdr);
/* SIGNING ---------------------------------------------------------------- */
if (ctx->flags & PDKIM_MODE_SIGN)
calculated, with GnuTLS we have to sign an entire block of headers
(due to available interfaces) and it recalculates the hash internally. */
-#if defined(SIGN_OPENSSL) || defined(SIGN_GCRYPT)
- hdata = hhash;
+#if defined(SIGN_GNUTLS)
+ hhash.data = hdata->s;
+ hhash.len = hdata->ptr;
#endif
/*XXX extend for non-RSA algos */
if ((*err = exim_dkim_sign(&sctx,
pdkim_hashes[sig->hashtype].exim_hashmethod,
- &hdata, &sig->sighash)))
+ &hhash, &sig->sighash)))
{
DEBUG(D_acl) debug_printf("signing: %s\n", *err);
return PDKIM_ERR_RSA_SIGNING;
projects / exim.git / blobdiff