openssl/crypto/asn1/asn_mime.c

976 lines
28 KiB
C

/*
* Copyright 2008-2020 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include "crypto/ctype.h"
#include "internal/cryptlib.h"
#include <openssl/rand.h>
#include <openssl/x509.h>
#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include "crypto/evp.h"
#include "internal/bio.h"
#include "asn1_local.h"
/*
* Generalised MIME like utilities for streaming ASN1. Although many have a
* PKCS7/CMS like flavour others are more general purpose.
*/
/*
* MIME format structures Note that all are translated to lower case apart
* from parameter values. Quotes are stripped off
*/
struct mime_param_st {
char *param_name; /* Param name e.g. "micalg" */
char *param_value; /* Param value e.g. "sha1" */
};
struct mime_header_st {
char *name; /* Name of line e.g. "content-type" */
char *value; /* Value of line e.g. "text/plain" */
STACK_OF(MIME_PARAM) *params; /* Zero or more parameters */
};
static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags,
const ASN1_ITEM *it);
static char *strip_ends(char *name);
static char *strip_start(char *name);
static char *strip_end(char *name);
static MIME_HEADER *mime_hdr_new(const char *name, const char *value);
static int mime_hdr_addparam(MIME_HEADER *mhdr, const char *name, const char *value);
static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio);
static int mime_hdr_cmp(const MIME_HEADER *const *a,
const MIME_HEADER *const *b);
static int mime_param_cmp(const MIME_PARAM *const *a,
const MIME_PARAM *const *b);
static void mime_param_free(MIME_PARAM *param);
static int mime_bound_check(char *line, int linelen, const char *bound, int blen);
static int multi_split(BIO *bio, const char *bound, STACK_OF(BIO) **ret);
static int strip_eol(char *linebuf, int *plen, int flags);
static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, const char *name);
static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, const char *name);
static void mime_hdr_free(MIME_HEADER *hdr);
#define MAX_SMLEN 1024
#define mime_debug(x) /* x */
/* Output an ASN1 structure in BER format streaming if necessary */
int i2d_ASN1_bio_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
const ASN1_ITEM *it)
{
/* If streaming create stream BIO and copy all content through it */
if (flags & SMIME_STREAM) {
BIO *bio, *tbio;
bio = BIO_new_NDEF(out, val, it);
if (!bio) {
ASN1err(ASN1_F_I2D_ASN1_BIO_STREAM, ERR_R_MALLOC_FAILURE);
return 0;
}
SMIME_crlf_copy(in, bio, flags);
(void)BIO_flush(bio);
/* Free up successive BIOs until we hit the old output BIO */
do {
tbio = BIO_pop(bio);
BIO_free(bio);
bio = tbio;
} while (bio != out);
}
/*
* else just write out ASN1 structure which will have all content stored
* internally
*/
else
ASN1_item_i2d_bio(it, out, val);
return 1;
}
/* Base 64 read and write of ASN1 structure */
static int B64_write_ASN1(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
const ASN1_ITEM *it)
{
BIO *b64;
int r;
b64 = BIO_new(BIO_f_base64());
if (b64 == NULL) {
ASN1err(ASN1_F_B64_WRITE_ASN1, ERR_R_MALLOC_FAILURE);
return 0;
}
/*
* prepend the b64 BIO so all data is base64 encoded.
*/
out = BIO_push(b64, out);
r = i2d_ASN1_bio_stream(out, val, in, flags, it);
(void)BIO_flush(out);
BIO_pop(out);
BIO_free(b64);
return r;
}
/* Streaming ASN1 PEM write */
int PEM_write_bio_ASN1_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
const char *hdr, const ASN1_ITEM *it)
{
int r;
BIO_printf(out, "-----BEGIN %s-----\n", hdr);
r = B64_write_ASN1(out, val, in, flags, it);
BIO_printf(out, "-----END %s-----\n", hdr);
return r;
}
static ASN1_VALUE *b64_read_asn1(BIO *bio, const ASN1_ITEM *it)
{
BIO *b64;
ASN1_VALUE *val;
if ((b64 = BIO_new(BIO_f_base64())) == NULL) {
ASN1err(ASN1_F_B64_READ_ASN1, ERR_R_MALLOC_FAILURE);
return 0;
}
bio = BIO_push(b64, bio);
val = ASN1_item_d2i_bio(it, bio, NULL);
if (!val)
ASN1err(ASN1_F_B64_READ_ASN1, ASN1_R_DECODE_ERROR);
(void)BIO_flush(bio);
BIO_pop(bio);
BIO_free(b64);
return val;
}
/* Generate the MIME "micalg" parameter from RFC3851, RFC4490 */
static int asn1_write_micalg(BIO *out, STACK_OF(X509_ALGOR) *mdalgs)
{
const EVP_MD *md;
int i, have_unknown = 0, write_comma, ret = 0, md_nid;
have_unknown = 0;
write_comma = 0;
for (i = 0; i < sk_X509_ALGOR_num(mdalgs); i++) {
if (write_comma)
BIO_write(out, ",", 1);
write_comma = 1;
md_nid = OBJ_obj2nid(sk_X509_ALGOR_value(mdalgs, i)->algorithm);
md = EVP_get_digestbynid(md_nid);
if (md && md->md_ctrl) {
int rv;
char *micstr;
rv = md->md_ctrl(NULL, EVP_MD_CTRL_MICALG, 0, &micstr);
if (rv > 0) {
BIO_puts(out, micstr);
OPENSSL_free(micstr);
continue;
}
if (rv != -2)
goto err;
}
switch (md_nid) {
case NID_sha1:
BIO_puts(out, "sha1");
break;
case NID_md5:
BIO_puts(out, "md5");
break;
case NID_sha256:
BIO_puts(out, "sha-256");
break;
case NID_sha384:
BIO_puts(out, "sha-384");
break;
case NID_sha512:
BIO_puts(out, "sha-512");
break;
case NID_id_GostR3411_94:
BIO_puts(out, "gostr3411-94");
goto err;
case NID_id_GostR3411_2012_256:
BIO_puts(out, "gostr3411-2012-256");
goto err;
case NID_id_GostR3411_2012_512:
BIO_puts(out, "gostr3411-2012-512");
goto err;
default:
if (have_unknown)
write_comma = 0;
else {
BIO_puts(out, "unknown");
have_unknown = 1;
}
break;
}
}
ret = 1;
err:
return ret;
}
/* SMIME sender */
int SMIME_write_ASN1(BIO *bio, ASN1_VALUE *val, BIO *data, int flags,
int ctype_nid, int econt_nid,
STACK_OF(X509_ALGOR) *mdalgs, const ASN1_ITEM *it)
{
char bound[33], c;
int i;
const char *mime_prefix, *mime_eol, *cname = "smime.p7m";
const char *msg_type = NULL;
if (flags & SMIME_OLDMIME)
mime_prefix = "application/x-pkcs7-";
else
mime_prefix = "application/pkcs7-";
if (flags & SMIME_CRLFEOL)
mime_eol = "\r\n";
else
mime_eol = "\n";
if ((flags & SMIME_DETACHED) && data) {
/* We want multipart/signed */
/* Generate a random boundary */
if (RAND_bytes((unsigned char *)bound, 32) <= 0)
return 0;
for (i = 0; i < 32; i++) {
c = bound[i] & 0xf;
if (c < 10)
c += '0';
else
c += 'A' - 10;
bound[i] = c;
}
bound[32] = 0;
BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
BIO_printf(bio, "Content-Type: multipart/signed;");
BIO_printf(bio, " protocol=\"%ssignature\";", mime_prefix);
BIO_puts(bio, " micalg=\"");
asn1_write_micalg(bio, mdalgs);
BIO_printf(bio, "\"; boundary=\"----%s\"%s%s",
bound, mime_eol, mime_eol);
BIO_printf(bio, "This is an S/MIME signed message%s%s",
mime_eol, mime_eol);
/* Now write out the first part */
BIO_printf(bio, "------%s%s", bound, mime_eol);
if (!asn1_output_data(bio, data, val, flags, it))
return 0;
BIO_printf(bio, "%s------%s%s", mime_eol, bound, mime_eol);
/* Headers for signature */
BIO_printf(bio, "Content-Type: %ssignature;", mime_prefix);
BIO_printf(bio, " name=\"smime.p7s\"%s", mime_eol);
BIO_printf(bio, "Content-Transfer-Encoding: base64%s", mime_eol);
BIO_printf(bio, "Content-Disposition: attachment;");
BIO_printf(bio, " filename=\"smime.p7s\"%s%s", mime_eol, mime_eol);
B64_write_ASN1(bio, val, NULL, 0, it);
BIO_printf(bio, "%s------%s--%s%s", mime_eol, bound,
mime_eol, mime_eol);
return 1;
}
/* Determine smime-type header */
if (ctype_nid == NID_pkcs7_enveloped)
msg_type = "enveloped-data";
else if (ctype_nid == NID_pkcs7_signed) {
if (econt_nid == NID_id_smime_ct_receipt)
msg_type = "signed-receipt";
else if (sk_X509_ALGOR_num(mdalgs) >= 0)
msg_type = "signed-data";
else
msg_type = "certs-only";
} else if (ctype_nid == NID_id_smime_ct_compressedData) {
msg_type = "compressed-data";
cname = "smime.p7z";
}
/* MIME headers */
BIO_printf(bio, "MIME-Version: 1.0%s", mime_eol);
BIO_printf(bio, "Content-Disposition: attachment;");
BIO_printf(bio, " filename=\"%s\"%s", cname, mime_eol);
BIO_printf(bio, "Content-Type: %smime;", mime_prefix);
if (msg_type)
BIO_printf(bio, " smime-type=%s;", msg_type);
BIO_printf(bio, " name=\"%s\"%s", cname, mime_eol);
BIO_printf(bio, "Content-Transfer-Encoding: base64%s%s",
mime_eol, mime_eol);
if (!B64_write_ASN1(bio, val, data, flags, it))
return 0;
BIO_printf(bio, "%s", mime_eol);
return 1;
}
/* Handle output of ASN1 data */
static int asn1_output_data(BIO *out, BIO *data, ASN1_VALUE *val, int flags,
const ASN1_ITEM *it)
{
BIO *tmpbio;
const ASN1_AUX *aux = it->funcs;
ASN1_STREAM_ARG sarg;
int rv = 1;
/*
* If data is not detached or resigning then the output BIO is already
* set up to finalise when it is written through.
*/
if (!(flags & SMIME_DETACHED) || (flags & PKCS7_REUSE_DIGEST)) {
SMIME_crlf_copy(data, out, flags);
return 1;
}
if (!aux || !aux->asn1_cb) {
ASN1err(ASN1_F_ASN1_OUTPUT_DATA, ASN1_R_STREAMING_NOT_SUPPORTED);
return 0;
}
sarg.out = out;
sarg.ndef_bio = NULL;
sarg.boundary = NULL;
/* Let ASN1 code prepend any needed BIOs */
if (aux->asn1_cb(ASN1_OP_DETACHED_PRE, &val, it, &sarg) <= 0)
return 0;
/* Copy data across, passing through filter BIOs for processing */
SMIME_crlf_copy(data, sarg.ndef_bio, flags);
/* Finalize structure */
if (aux->asn1_cb(ASN1_OP_DETACHED_POST, &val, it, &sarg) <= 0)
rv = 0;
/* Now remove any digests prepended to the BIO */
while (sarg.ndef_bio != out) {
tmpbio = BIO_pop(sarg.ndef_bio);
BIO_free(sarg.ndef_bio);
sarg.ndef_bio = tmpbio;
}
return rv;
}
/*
* SMIME reader: handle multipart/signed and opaque signing. in multipart
* case the content is placed in a memory BIO pointed to by "bcont". In
* opaque this is set to NULL
*/
ASN1_VALUE *SMIME_read_ASN1(BIO *bio, BIO **bcont, const ASN1_ITEM *it)
{
BIO *asnin;
STACK_OF(MIME_HEADER) *headers = NULL;
STACK_OF(BIO) *parts = NULL;
MIME_HEADER *hdr;
MIME_PARAM *prm;
ASN1_VALUE *val;
int ret;
if (bcont)
*bcont = NULL;
if ((headers = mime_parse_hdr(bio)) == NULL) {
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_MIME_PARSE_ERROR);
return NULL;
}
if ((hdr = mime_hdr_find(headers, "content-type")) == NULL
|| hdr->value == NULL) {
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_CONTENT_TYPE);
return NULL;
}
/* Handle multipart/signed */
if (strcmp(hdr->value, "multipart/signed") == 0) {
/* Split into two parts */
prm = mime_param_find(hdr, "boundary");
if (!prm || !prm->param_value) {
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_MULTIPART_BOUNDARY);
return NULL;
}
ret = multi_split(bio, prm->param_value, &parts);
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
if (!ret || (sk_BIO_num(parts) != 2)) {
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_MULTIPART_BODY_FAILURE);
sk_BIO_pop_free(parts, BIO_vfree);
return NULL;
}
/* Parse the signature piece */
asnin = sk_BIO_value(parts, 1);
if ((headers = mime_parse_hdr(asnin)) == NULL) {
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_MIME_SIG_PARSE_ERROR);
sk_BIO_pop_free(parts, BIO_vfree);
return NULL;
}
/* Get content type */
if ((hdr = mime_hdr_find(headers, "content-type")) == NULL
|| hdr->value == NULL) {
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_NO_SIG_CONTENT_TYPE);
sk_BIO_pop_free(parts, BIO_vfree);
return NULL;
}
if (strcmp(hdr->value, "application/x-pkcs7-signature") &&
strcmp(hdr->value, "application/pkcs7-signature")) {
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_SIG_INVALID_MIME_TYPE);
ERR_add_error_data(2, "type: ", hdr->value);
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
sk_BIO_pop_free(parts, BIO_vfree);
return NULL;
}
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
/* Read in ASN1 */
if ((val = b64_read_asn1(asnin, it)) == NULL) {
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_ASN1_SIG_PARSE_ERROR);
sk_BIO_pop_free(parts, BIO_vfree);
return NULL;
}
if (bcont) {
*bcont = sk_BIO_value(parts, 0);
BIO_free(asnin);
sk_BIO_free(parts);
} else
sk_BIO_pop_free(parts, BIO_vfree);
return val;
}
/* OK, if not multipart/signed try opaque signature */
if (strcmp(hdr->value, "application/x-pkcs7-mime") &&
strcmp(hdr->value, "application/pkcs7-mime")) {
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_INVALID_MIME_TYPE);
ERR_add_error_data(2, "type: ", hdr->value);
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
return NULL;
}
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
if ((val = b64_read_asn1(bio, it)) == NULL) {
ASN1err(ASN1_F_SMIME_READ_ASN1, ASN1_R_ASN1_PARSE_ERROR);
return NULL;
}
return val;
}
/* Copy text from one BIO to another making the output CRLF at EOL */
int SMIME_crlf_copy(BIO *in, BIO *out, int flags)
{
BIO *bf;
char eol;
int len;
char linebuf[MAX_SMLEN];
int ret;
/*
* Buffer output so we don't write one line at a time. This is useful
* when streaming as we don't end up with one OCTET STRING per line.
*/
bf = BIO_new(BIO_f_buffer());
if (bf == NULL)
return 0;
out = BIO_push(bf, out);
if (flags & SMIME_BINARY) {
while ((len = BIO_read(in, linebuf, MAX_SMLEN)) > 0)
BIO_write(out, linebuf, len);
} else {
int eolcnt = 0;
if (flags & SMIME_TEXT)
BIO_printf(out, "Content-Type: text/plain\r\n\r\n");
while ((len = BIO_gets(in, linebuf, MAX_SMLEN)) > 0) {
eol = strip_eol(linebuf, &len, flags);
if (len) {
/* Not EOF: write out all CRLF */
if (flags & SMIME_ASCIICRLF) {
int i;
for (i = 0; i < eolcnt; i++)
BIO_write(out, "\r\n", 2);
eolcnt = 0;
}
BIO_write(out, linebuf, len);
if (eol)
BIO_write(out, "\r\n", 2);
} else if (flags & SMIME_ASCIICRLF)
eolcnt++;
else if (eol)
BIO_write(out, "\r\n", 2);
}
}
ret = BIO_flush(out);
BIO_pop(out);
BIO_free(bf);
if (ret <= 0)
return 0;
return 1;
}
/* Strip off headers if they are text/plain */
int SMIME_text(BIO *in, BIO *out)
{
char iobuf[4096];
int len;
STACK_OF(MIME_HEADER) *headers;
MIME_HEADER *hdr;
if ((headers = mime_parse_hdr(in)) == NULL) {
ASN1err(ASN1_F_SMIME_TEXT, ASN1_R_MIME_PARSE_ERROR);
return 0;
}
if ((hdr = mime_hdr_find(headers, "content-type")) == NULL
|| hdr->value == NULL) {
ASN1err(ASN1_F_SMIME_TEXT, ASN1_R_MIME_NO_CONTENT_TYPE);
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
return 0;
}
if (strcmp(hdr->value, "text/plain")) {
ASN1err(ASN1_F_SMIME_TEXT, ASN1_R_INVALID_MIME_TYPE);
ERR_add_error_data(2, "type: ", hdr->value);
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
return 0;
}
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0)
BIO_write(out, iobuf, len);
if (len < 0)
return 0;
return 1;
}
/*
* Split a multipart/XXX message body into component parts: result is
* canonical parts in a STACK of bios
*/
static int multi_split(BIO *bio, const char *bound, STACK_OF(BIO) **ret)
{
char linebuf[MAX_SMLEN];
int len, blen;
int eol = 0, next_eol = 0;
BIO *bpart = NULL;
STACK_OF(BIO) *parts;
char state, part, first;
blen = strlen(bound);
part = 0;
state = 0;
first = 1;
parts = sk_BIO_new_null();
*ret = parts;
if (*ret == NULL)
return 0;
while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
state = mime_bound_check(linebuf, len, bound, blen);
if (state == 1) {
first = 1;
part++;
} else if (state == 2) {
if (!sk_BIO_push(parts, bpart)) {
BIO_free(bpart);
return 0;
}
return 1;
} else if (part) {
/* Strip CR+LF from linebuf */
next_eol = strip_eol(linebuf, &len, 0);
if (first) {
first = 0;
if (bpart)
if (!sk_BIO_push(parts, bpart)) {
BIO_free(bpart);
return 0;
}
bpart = BIO_new(BIO_s_mem());
if (bpart == NULL)
return 0;
BIO_set_mem_eof_return(bpart, 0);
} else if (eol)
BIO_write(bpart, "\r\n", 2);
eol = next_eol;
if (len)
BIO_write(bpart, linebuf, len);
}
}
BIO_free(bpart);
return 0;
}
/* This is the big one: parse MIME header lines up to message body */
#define MIME_INVALID 0
#define MIME_START 1
#define MIME_TYPE 2
#define MIME_NAME 3
#define MIME_VALUE 4
#define MIME_QUOTE 5
#define MIME_COMMENT 6
static STACK_OF(MIME_HEADER) *mime_parse_hdr(BIO *bio)
{
char *p, *q, c;
char *ntmp;
char linebuf[MAX_SMLEN];
MIME_HEADER *mhdr = NULL, *new_hdr = NULL;
STACK_OF(MIME_HEADER) *headers;
int len, state, save_state = 0;
headers = sk_MIME_HEADER_new(mime_hdr_cmp);
if (headers == NULL)
return NULL;
while ((len = BIO_gets(bio, linebuf, MAX_SMLEN)) > 0) {
/* If whitespace at line start then continuation line */
if (mhdr && ossl_isspace(linebuf[0]))
state = MIME_NAME;
else
state = MIME_START;
ntmp = NULL;
/* Go through all characters */
for (p = linebuf, q = linebuf; (c = *p) && (c != '\r') && (c != '\n');
p++) {
/*
* State machine to handle MIME headers if this looks horrible
* that's because it *is*
*/
switch (state) {
case MIME_START:
if (c == ':') {
state = MIME_TYPE;
*p = 0;
ntmp = strip_ends(q);
q = p + 1;
}
break;
case MIME_TYPE:
if (c == ';') {
mime_debug("Found End Value\n");
*p = 0;
new_hdr = mime_hdr_new(ntmp, strip_ends(q));
if (new_hdr == NULL)
goto err;
if (!sk_MIME_HEADER_push(headers, new_hdr))
goto err;
mhdr = new_hdr;
new_hdr = NULL;
ntmp = NULL;
q = p + 1;
state = MIME_NAME;
} else if (c == '(') {
save_state = state;
state = MIME_COMMENT;
}
break;
case MIME_COMMENT:
if (c == ')') {
state = save_state;
}
break;
case MIME_NAME:
if (c == '=') {
state = MIME_VALUE;
*p = 0;
ntmp = strip_ends(q);
q = p + 1;
}
break;
case MIME_VALUE:
if (c == ';') {
state = MIME_NAME;
*p = 0;
mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
ntmp = NULL;
q = p + 1;
} else if (c == '"') {
mime_debug("Found Quote\n");
state = MIME_QUOTE;
} else if (c == '(') {
save_state = state;
state = MIME_COMMENT;
}
break;
case MIME_QUOTE:
if (c == '"') {
mime_debug("Found Match Quote\n");
state = MIME_VALUE;
}
break;
}
}
if (state == MIME_TYPE) {
new_hdr = mime_hdr_new(ntmp, strip_ends(q));
if (new_hdr == NULL)
goto err;
if (!sk_MIME_HEADER_push(headers, new_hdr))
goto err;
mhdr = new_hdr;
new_hdr = NULL;
} else if (state == MIME_VALUE)
mime_hdr_addparam(mhdr, ntmp, strip_ends(q));
if (p == linebuf)
break; /* Blank line means end of headers */
}
return headers;
err:
mime_hdr_free(new_hdr);
sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
return NULL;
}
static char *strip_ends(char *name)
{
return strip_end(strip_start(name));
}
/* Strip a parameter of whitespace from start of param */
static char *strip_start(char *name)
{
char *p, c;
/* Look for first non white space or quote */
for (p = name; (c = *p); p++) {
if (c == '"') {
/* Next char is start of string if non null */
if (p[1])
return p + 1;
/* Else null string */
return NULL;
}
if (!ossl_isspace(c))
return p;
}
return NULL;
}
/* As above but strip from end of string : maybe should handle brackets? */
static char *strip_end(char *name)
{
char *p, c;
if (!name)
return NULL;
/* Look for first non white space or quote */
for (p = name + strlen(name) - 1; p >= name; p--) {
c = *p;
if (c == '"') {
if (p - 1 == name)
return NULL;
*p = 0;
return name;
}
if (ossl_isspace(c))
*p = 0;
else
return name;
}
return NULL;
}
static MIME_HEADER *mime_hdr_new(const char *name, const char *value)
{
MIME_HEADER *mhdr = NULL;
char *tmpname = NULL, *tmpval = NULL, *p;
if (name) {
if ((tmpname = OPENSSL_strdup(name)) == NULL)
return NULL;
for (p = tmpname; *p; p++)
*p = ossl_tolower(*p);
}
if (value) {
if ((tmpval = OPENSSL_strdup(value)) == NULL)
goto err;
for (p = tmpval; *p; p++)
*p = ossl_tolower(*p);
}
mhdr = OPENSSL_malloc(sizeof(*mhdr));
if (mhdr == NULL)
goto err;
mhdr->name = tmpname;
mhdr->value = tmpval;
if ((mhdr->params = sk_MIME_PARAM_new(mime_param_cmp)) == NULL)
goto err;
return mhdr;
err:
OPENSSL_free(tmpname);
OPENSSL_free(tmpval);
OPENSSL_free(mhdr);
return NULL;
}
static int mime_hdr_addparam(MIME_HEADER *mhdr, const char *name, const char *value)
{
char *tmpname = NULL, *tmpval = NULL, *p;
MIME_PARAM *mparam = NULL;
if (name) {
tmpname = OPENSSL_strdup(name);
if (!tmpname)
goto err;
for (p = tmpname; *p; p++)
*p = ossl_tolower(*p);
}
if (value) {
tmpval = OPENSSL_strdup(value);
if (!tmpval)
goto err;
}
/* Parameter values are case sensitive so leave as is */
mparam = OPENSSL_malloc(sizeof(*mparam));
if (mparam == NULL)
goto err;
mparam->param_name = tmpname;
mparam->param_value = tmpval;
if (!sk_MIME_PARAM_push(mhdr->params, mparam))
goto err;
return 1;
err:
OPENSSL_free(tmpname);
OPENSSL_free(tmpval);
OPENSSL_free(mparam);
return 0;
}
static int mime_hdr_cmp(const MIME_HEADER *const *a,
const MIME_HEADER *const *b)
{
if (!(*a)->name || !(*b)->name)
return ! !(*a)->name - ! !(*b)->name;
return strcmp((*a)->name, (*b)->name);
}
static int mime_param_cmp(const MIME_PARAM *const *a,
const MIME_PARAM *const *b)
{
if (!(*a)->param_name || !(*b)->param_name)
return ! !(*a)->param_name - ! !(*b)->param_name;
return strcmp((*a)->param_name, (*b)->param_name);
}
/* Find a header with a given name (if possible) */
static MIME_HEADER *mime_hdr_find(STACK_OF(MIME_HEADER) *hdrs, const char *name)
{
MIME_HEADER htmp;
int idx;
htmp.name = (char *)name;
htmp.value = NULL;
htmp.params = NULL;
idx = sk_MIME_HEADER_find(hdrs, &htmp);
return sk_MIME_HEADER_value(hdrs, idx);
}
static MIME_PARAM *mime_param_find(MIME_HEADER *hdr, const char *name)
{
MIME_PARAM param;
int idx;
param.param_name = (char *)name;
param.param_value = NULL;
idx = sk_MIME_PARAM_find(hdr->params, &param);
return sk_MIME_PARAM_value(hdr->params, idx);
}
static void mime_hdr_free(MIME_HEADER *hdr)
{
if (hdr == NULL)
return;
OPENSSL_free(hdr->name);
OPENSSL_free(hdr->value);
if (hdr->params)
sk_MIME_PARAM_pop_free(hdr->params, mime_param_free);
OPENSSL_free(hdr);
}
static void mime_param_free(MIME_PARAM *param)
{
OPENSSL_free(param->param_name);
OPENSSL_free(param->param_value);
OPENSSL_free(param);
}
/*-
* Check for a multipart boundary. Returns:
* 0 : no boundary
* 1 : part boundary
* 2 : final boundary
*/
static int mime_bound_check(char *line, int linelen, const char *bound, int blen)
{
if (linelen == -1)
linelen = strlen(line);
if (blen == -1)
blen = strlen(bound);
/* Quickly eliminate if line length too short */
if (blen + 2 > linelen)
return 0;
/* Check for part boundary */
if ((strncmp(line, "--", 2) == 0)
&& strncmp(line + 2, bound, blen) == 0) {
if (strncmp(line + blen + 2, "--", 2) == 0)
return 2;
else
return 1;
}
return 0;
}
static int strip_eol(char *linebuf, int *plen, int flags)
{
int len = *plen;
char *p, c;
int is_eol = 0;
for (p = linebuf + len - 1; len > 0; len--, p--) {
c = *p;
if (c == '\n') {
is_eol = 1;
} else if (is_eol && flags & SMIME_ASCIICRLF && c == 32) {
/* Strip trailing space on a line; 32 == ASCII for ' ' */
continue;
} else if (c != '\r') {
break;
}
}
*plen = len;
return is_eol;
}