curl/lib/http_digest.c

464 lines
13 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2004, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at http://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* $Id$
***************************************************************************/
#include "setup.h"
#ifndef CURL_DISABLE_HTTP
/* -- WIN32 approved -- */
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <ctype.h>
#include "urldata.h"
#include "sendf.h"
#include "strequal.h"
#include "base64.h"
#include "md5.h"
#include "http_digest.h"
#include "strtok.h"
#include "url.h" /* for Curl_safefree() */
#include "memory.h"
#define _MPRINTF_REPLACE /* use our functions only */
#include <curl/mprintf.h>
/* The last #include file should be: */
#include "memdebug.h"
/* Test example headers:
WWW-Authenticate: Digest realm="testrealm", nonce="1053604598"
Proxy-Authenticate: Digest realm="testrealm", nonce="1053604598"
*/
CURLdigest Curl_input_digest(struct connectdata *conn,
bool proxy,
char *header) /* rest of the *-authenticate:
header */
{
bool more = TRUE;
char *token = NULL;
char *tmp = NULL;
bool foundAuth = FALSE;
bool foundAuthInt = FALSE;
struct SessionHandle *data=conn->data;
bool before = FALSE; /* got a nonce before */
struct digestdata *d;
if(proxy) {
d = &data->state.proxydigest;
}
else {
d = &data->state.digest;
}
/* skip initial whitespaces */
while(*header && isspace((int)*header))
header++;
if(checkprefix("Digest", header)) {
header += strlen("Digest");
/* If we already have received a nonce, keep that in mind */
if(d->nonce)
before = TRUE;
/* clear off any former leftovers and init to defaults */
Curl_digest_cleanup_one(d);
while(more) {
char value[32];
char content[128];
size_t totlen=0;
while(*header && isspace((int)*header))
header++;
/* how big can these strings be? */
if((2 == sscanf(header, "%31[^=]=\"%127[^\"]\"",
value, content)) ||
/* try the same scan but without quotes around the content but don't
include the possibly trailing comma */
(2 == sscanf(header, "%31[^=]=%127[^,]",
value, content)) ) {
if(strequal(value, "nonce")) {
d->nonce = strdup(content);
if(!d->nonce)
return CURLDIGEST_NOMEM;
}
else if(strequal(value, "stale")) {
if(strequal(content, "true")) {
d->stale = TRUE;
d->nc = 1; /* we make a new nonce now */
}
}
else if(strequal(value, "realm")) {
d->realm = strdup(content);
if(!d->realm)
return CURLDIGEST_NOMEM;
}
else if(strequal(value, "opaque")) {
d->opaque = strdup(content);
if(!d->opaque)
return CURLDIGEST_NOMEM;
}
else if(strequal(value, "qop")) {
char *tok_buf;
/* tokenize the list and choose auth if possible, use a temporary
clone of the buffer since strtok_r() ruins it */
tmp = strdup(content);
if(!tmp)
return CURLDIGEST_NOMEM;
token = strtok_r(tmp, ",", &tok_buf);
while (token != NULL) {
if (strequal(token, "auth")) {
foundAuth = TRUE;
}
else if (strequal(token, "auth-int")) {
foundAuthInt = TRUE;
}
token = strtok_r(NULL, ",", &tok_buf);
}
free(tmp);
/*select only auth o auth-int. Otherwise, ignore*/
if (foundAuth) {
d->qop = strdup("auth");
if(!d->qop)
return CURLDIGEST_NOMEM;
}
else if (foundAuthInt) {
d->qop = strdup("auth-int");
if(!d->qop)
return CURLDIGEST_NOMEM;
}
}
else if(strequal(value, "algorithm")) {
d->algorithm = strdup(content);
if(!d->algorithm)
return CURLDIGEST_NOMEM;
if(strequal(content, "MD5-sess"))
d->algo = CURLDIGESTALGO_MD5SESS;
else if(strequal(content, "MD5"))
d->algo = CURLDIGESTALGO_MD5;
else
return CURLDIGEST_BADALGO;
}
else {
/* unknown specifier, ignore it! */
}
totlen = strlen(value)+strlen(content)+3;
}
else
break; /* we're done here */
header += totlen;
if(',' == *header)
/* allow the list to be comma-separated */
header++;
}
/* We had a nonce since before, and we got another one now without
'stale=true'. This means we provided bad credentials in the previous
request */
if(before && !d->stale)
return CURLDIGEST_BAD;
/* We got this header without a nonce, that's a bad Digest line! */
if(!d->nonce)
return CURLDIGEST_BAD;
}
else
/* else not a digest, get out */
return CURLDIGEST_NONE;
return CURLDIGEST_FINE;
}
/* convert md5 chunk to RFC2617 (section 3.1.3) -suitable ascii string*/
static void md5_to_ascii(unsigned char *source, /* 16 bytes */
unsigned char *dest) /* 33 bytes */
{
int i;
for(i=0; i<16; i++)
sprintf((char *)&dest[i*2], "%02x", source[i]);
}
CURLcode Curl_output_digest(struct connectdata *conn,
bool proxy,
unsigned char *request,
unsigned char *uripath)
{
/* We have a Digest setup for this, use it! Now, to get all the details for
this sorted out, I must urge you dear friend to read up on the RFC2617
section 3.2.2, */
unsigned char md5buf[16]; /* 16 bytes/128 bits */
unsigned char request_digest[33];
unsigned char *md5this;
unsigned char *ha1;
unsigned char ha2[33];/* 32 digits and 1 zero byte */
char cnoncebuf[7];
char *cnonce;
char *tmp = NULL;
struct timeval now;
struct auth *authp;
char **userp;
struct SessionHandle *data = conn->data;
struct digestdata *d;
if(proxy) {
d = &data->state.proxydigest;
authp = &data->state.authproxy;
userp = &conn->allocptr.proxyuserpwd;
}
else {
d = &data->state.digest;
authp = &data->state.authhost;
userp = &conn->allocptr.userpwd;
}
if(!d->nonce) {
authp->done = FALSE;
return CURLE_OK;
}
authp->done = TRUE;
if(!d->nc)
d->nc = 1;
if(!d->cnonce) {
/* Generate a cnonce */
now = Curl_tvnow();
snprintf(cnoncebuf, sizeof(cnoncebuf), "%06ld", now.tv_sec);
if(Curl_base64_encode(cnoncebuf, strlen(cnoncebuf), &cnonce))
d->cnonce = cnonce;
else
return CURLE_OUT_OF_MEMORY;
}
/*
if the algorithm is "MD5" or unspecified (which then defaults to MD5):
A1 = unq(username-value) ":" unq(realm-value) ":" passwd
if the algorithm is "MD5-sess" then:
A1 = H( unq(username-value) ":" unq(realm-value) ":" passwd )
":" unq(nonce-value) ":" unq(cnonce-value)
*/
md5this = (unsigned char *)
aprintf("%s:%s:%s", conn->user, d->realm, conn->passwd);
if(!md5this)
return CURLE_OUT_OF_MEMORY;
Curl_md5it(md5buf, md5this);
free(md5this); /* free this again */
ha1 = (unsigned char *)malloc(33); /* 32 digits and 1 zero byte */
if(!ha1)
return CURLE_OUT_OF_MEMORY;
md5_to_ascii(md5buf, ha1);
if(d->algo == CURLDIGESTALGO_MD5SESS) {
/* nonce and cnonce are OUTSIDE the hash */
tmp = aprintf("%s:%s:%s", ha1, d->nonce, d->cnonce);
free(ha1);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
ha1 = (unsigned char *)tmp;
}
/*
If the "qop" directive's value is "auth" or is unspecified, then A2 is:
A2 = Method ":" digest-uri-value
If the "qop" value is "auth-int", then A2 is:
A2 = Method ":" digest-uri-value ":" H(entity-body)
(The "Method" value is the HTTP request method as specified in section
5.1.1 of RFC 2616)
*/
md5this = (unsigned char *)aprintf("%s:%s", request, uripath);
if(!md5this) {
free(ha1);
return CURLE_OUT_OF_MEMORY;
}
if (d->qop && strequal(d->qop, "auth-int")) {
/* We don't support auth-int at the moment. I can't see a easy way to get
entity-body here */
/* TODO: Append H(entity-body)*/
}
Curl_md5it(md5buf, md5this);
free(md5this); /* free this again */
md5_to_ascii(md5buf, ha2);
if (d->qop) {
md5this = (unsigned char *)aprintf("%s:%s:%08x:%s:%s:%s",
ha1,
d->nonce,
d->nc,
d->cnonce,
d->qop,
ha2);
}
else {
md5this = (unsigned char *)aprintf("%s:%s:%s",
ha1,
d->nonce,
ha2);
}
free(ha1);
if(!md5this)
return CURLE_OUT_OF_MEMORY;
Curl_md5it(md5buf, md5this);
free(md5this); /* free this again */
md5_to_ascii(md5buf, request_digest);
/* for test case 64 (snooped from a Mozilla 1.3a request)
Authorization: Digest username="testuser", realm="testrealm", \
nonce="1053604145", uri="/64", response="c55f7f30d83d774a3d2dcacf725abaca"
*/
Curl_safefree(conn->allocptr.userpwd);
if (d->qop) {
*userp =
aprintf( "%sAuthorization: Digest "
"username=\"%s\", "
"realm=\"%s\", "
"nonce=\"%s\", "
"uri=\"%s\", "
"cnonce=\"%s\", "
"nc=%08x, "
"qop=\"%s\", "
"response=\"%s\"",
proxy?"Proxy-":"",
conn->user,
d->realm,
d->nonce,
uripath, /* this is the PATH part of the URL */
d->cnonce,
d->nc,
d->qop,
request_digest);
if(strequal(d->qop, "auth"))
d->nc++; /* The nc (from RFC) has to be a 8 hex digit number 0 padded
which tells to the server how many times you are using the
same nonce in the qop=auth mode. */
}
else {
*userp =
aprintf( "%sAuthorization: Digest "
"username=\"%s\", "
"realm=\"%s\", "
"nonce=\"%s\", "
"uri=\"%s\", "
"response=\"%s\"",
proxy?"Proxy-":"",
conn->user,
d->realm,
d->nonce,
uripath, /* this is the PATH part of the URL */
request_digest);
}
if(!*userp)
return CURLE_OUT_OF_MEMORY;
/* Add optional fields */
if(d->opaque) {
/* append opaque */
tmp = aprintf("%s, opaque=\"%s\"", *userp, d->opaque);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
free(*userp);
*userp = tmp;
}
if(d->algorithm) {
/* append algorithm */
tmp = aprintf("%s, algorithm=\"%s\"", *userp, d->algorithm);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
free(*userp);
*userp = tmp;
}
/* append CRLF to the userpwd header */
tmp = (char*) realloc(*userp, strlen(*userp) + 3 + 1);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
strcat(tmp, "\r\n");
*userp = tmp;
return CURLE_OK;
}
void Curl_digest_cleanup_one(struct digestdata *d)
{
if(d->nonce)
free(d->nonce);
d->nonce = NULL;
if(d->cnonce)
free(d->cnonce);
d->cnonce = NULL;
if(d->realm)
free(d->realm);
d->realm = NULL;
if(d->opaque)
free(d->opaque);
d->opaque = NULL;
if(d->qop)
free(d->qop);
d->qop = NULL;
if(d->algorithm)
free(d->algorithm);
d->algorithm = NULL;
d->nc = 0;
d->algo = CURLDIGESTALGO_MD5; /* default algorithm */
d->stale = FALSE; /* default means normal, not stale */
}
void Curl_digest_cleanup(struct SessionHandle *data)
{
Curl_digest_cleanup_one(&data->state.digest);
Curl_digest_cleanup_one(&data->state.proxydigest);
}
#endif