CURLcode Curl_output_digest(struct connectdata *conn,
bool proxy,
const unsigned char *request,
const 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, */
size_t urilen;
unsigned char md5buf[16]; /* 16 bytes/128 bits */
unsigned char request_digest[33];
unsigned char *md5this;
unsigned char ha1[33];/* 32 digits and 1 zero byte */
unsigned char ha2[33];/* 32 digits and 1 zero byte */
char cnoncebuf[33];
char *cnonce = NULL;
size_t cnonce_sz = 0;
char *tmp = NULL;
char **allocuserpwd;
size_t userlen;
const char *userp;
char *userp_quoted;
const char *passwdp;
struct auth *authp;
struct SessionHandle *data = conn->data;
struct digestdata *d;
CURLcode result;
/* The CURL_OUTPUT_DIGEST_CONV macro below is for non-ASCII machines.
It converts digest text to ASCII so the MD5 will be correct for
what ultimately goes over the network.
*/
#define CURL_OUTPUT_DIGEST_CONV(a, b) \
result = Curl_convert_to_network(a, (char *)b, strlen((const char*)b)); \
if(result) { \
free(b); \
return result; \
}
if(proxy) {
d = &data->state.proxydigest;
allocuserpwd = &conn->allocptr.proxyuserpwd;
userp = conn->proxyuser;
passwdp = conn->proxypasswd;
authp = &data->state.authproxy;
}
else {
d = &data->state.digest;
allocuserpwd = &conn->allocptr.userpwd;
userp = conn->user;
passwdp = conn->passwd;
authp = &data->state.authhost;
}
Curl_safefree(*allocuserpwd);
/* not set means empty */
if(!userp)
userp="";
if(!passwdp)
passwdp="";
if(!d->nonce) {
authp->done = FALSE;
return CURLE_OK;
}
authp->done = TRUE;
if(!d->nc)
d->nc = 1;
if(!d->cnonce) {
snprintf(cnoncebuf, sizeof(cnoncebuf), "%08x%08x%08x%08x",
Curl_rand(data), Curl_rand(data),
Curl_rand(data), Curl_rand(data));
result = Curl_base64_encode(data, cnoncebuf, strlen(cnoncebuf),
&cnonce, &cnonce_sz);
if(result)
return result;
d->cnonce = cnonce;
}
/*
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", userp, d->realm, passwdp);
if(!md5this)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, md5this); /* convert on non-ASCII machines */
Curl_md5it(md5buf, md5this);
Curl_safefree(md5this);
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);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, tmp); /* convert on non-ASCII machines */
Curl_md5it(md5buf, (unsigned char *)tmp);
Curl_safefree(tmp);
md5_to_ascii(md5buf, ha1);
}
/*
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)
*/
/* So IE browsers < v7 cut off the URI part at the query part when they
evaluate the MD5 and some (IIS?) servers work with them so we may need to
do the Digest IE-style. Note that the different ways cause different MD5
sums to get sent.
Apache servers can be set to do the Digest IE-style automatically using
the BrowserMatch feature:
http://httpd.apache.org/docs/2.2/mod/mod_auth_digest.html#msie
Further details on Digest implementation differences:
http://www.fngtps.com/2006/09/http-authentication
*/
if(authp->iestyle && ((tmp = strchr((char *)uripath, '?')) != NULL))
urilen = tmp - (char *)uripath;
else
urilen = strlen((char *)uripath);
md5this = (unsigned char *)aprintf("%s:%.*s", request, urilen, uripath);
if(d->qop && Curl_raw_equal(d->qop, "auth-int")) {
/* We don't support auth-int for PUT or POST at the moment.
TODO: replace md5 of empty string with entity-body for PUT/POST */
unsigned char *md5this2 = (unsigned char *)
aprintf("%s:%s", md5this, "d41d8cd98f00b204e9800998ecf8427e");
Curl_safefree(md5this);
md5this = md5this2;
}
if(!md5this)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, md5this); /* convert on non-ASCII machines */
Curl_md5it(md5buf, md5this);
Curl_safefree(md5this);
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);
}
if(!md5this)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, md5this); /* convert on non-ASCII machines */
Curl_md5it(md5buf, md5this);
Curl_safefree(md5this);
md5_to_ascii(md5buf, request_digest);
/* for test case 64 (snooped from a Mozilla 1.3a request)
Authorization: Digest username="******", realm="testrealm", \
nonce="1053604145", uri="/64", response="c55f7f30d83d774a3d2dcacf725abaca"
Digest parameters are all quoted strings. Username which is provided by
the user will need double quotes and backslashes within it escaped. For
the other fields, this shouldn't be an issue. realm, nonce, and opaque
are copied as is from the server, escapes and all. cnonce is generated
with web-safe characters. uri is already percent encoded. nc is 8 hex
characters. algorithm and qop with standard values only contain web-safe
chracters.
*/
userp_quoted = string_quoted(userp);
if(!userp_quoted)
return CURLE_OUT_OF_MEMORY;
if(d->qop) {
*allocuserpwd =
aprintf( "%sAuthorization: Digest "
"username=\"%s\", "
"realm=\"%s\", "
"nonce=\"%s\", "
"uri=\"%.*s\", "
"cnonce=\"%s\", "
"nc=%08x, "
"qop=%s, "
"response=\"%s\"",
proxy?"Proxy-":"",
userp_quoted,
d->realm,
d->nonce,
urilen, uripath, /* this is the PATH part of the URL */
d->cnonce,
d->nc,
d->qop,
request_digest);
if(Curl_raw_equal(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 {
*allocuserpwd =
aprintf( "%sAuthorization: Digest "
"username=\"%s\", "
"realm=\"%s\", "
"nonce=\"%s\", "
"uri=\"%.*s\", "
"response=\"%s\"",
proxy?"Proxy-":"",
userp_quoted,
d->realm,
d->nonce,
urilen, uripath, /* this is the PATH part of the URL */
request_digest);
}
Curl_safefree(userp_quoted);
if(!*allocuserpwd)
return CURLE_OUT_OF_MEMORY;
/* Add optional fields */
if(d->opaque) {
/* append opaque */
tmp = aprintf("%s, opaque=\"%s\"", *allocuserpwd, d->opaque);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
free(*allocuserpwd);
*allocuserpwd = tmp;
}
if(d->algorithm) {
/* append algorithm */
tmp = aprintf("%s, algorithm=\"%s\"", *allocuserpwd, d->algorithm);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
free(*allocuserpwd);
*allocuserpwd = tmp;
}
/* append CRLF + zero (3 bytes) to the userpwd header */
userlen = strlen(*allocuserpwd);
tmp = realloc(*allocuserpwd, userlen + 3);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
strcpy(&tmp[userlen], "\r\n"); /* append the data */
*allocuserpwd = tmp;
return CURLE_OK;
}
CURLcode Curl_output_digest(struct connectdata *conn,
bool proxy,
const unsigned char *request,
const 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;
char **allocuserpwd;
const char *userp;
const char *passwdp;
struct auth *authp;
struct SessionHandle *data = conn->data;
struct digestdata *d;
#ifdef CURL_DOES_CONVERSIONS
CURLcode rc;
/* The CURL_OUTPUT_DIGEST_CONV macro below is for non-ASCII machines.
It converts digest text to ASCII so the MD5 will be correct for
what ultimately goes over the network.
*/
#define CURL_OUTPUT_DIGEST_CONV(a, b) \
rc = Curl_convert_to_network(a, (char *)b, strlen((const char*)b)); \
if(rc != CURLE_OK) { \
free(b); \
return rc; \
}
#else
#define CURL_OUTPUT_DIGEST_CONV(a, b)
#endif /* CURL_DOES_CONVERSIONS */
if(proxy) {
d = &data->state.proxydigest;
allocuserpwd = &conn->allocptr.proxyuserpwd;
userp = conn->proxyuser;
passwdp = conn->proxypasswd;
authp = &data->state.authproxy;
}
else {
d = &data->state.digest;
allocuserpwd = &conn->allocptr.userpwd;
userp = conn->user;
passwdp = conn->passwd;
authp = &data->state.authhost;
}
if(*allocuserpwd) {
Curl_safefree(*allocuserpwd);
*allocuserpwd = NULL;
}
/* not set means empty */
if(!userp)
userp="";
if(!passwdp)
passwdp="";
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", (long)now.tv_sec);
if(Curl_base64_encode(data, 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", userp, d->realm, passwdp);
if(!md5this)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, md5this); /* convert on non-ASCII machines */
Curl_md5it(md5buf, md5this);
free(md5this); /* free this again */
ha1 = 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);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, tmp); /* convert on non-ASCII machines */
Curl_md5it(md5buf, (unsigned char *)tmp);
free(tmp); /* free this again */
md5_to_ascii(md5buf, ha1);
}
/*
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)
*/
/* So IE browsers < v7 cut off the URI part at the query part when they
evaluate the MD5 and some (IIS?) servers work with them so we may need to
do the Digest IE-style. Note that the different ways cause different MD5
sums to get sent.
Apache servers can be set to do the Digest IE-style automatically using
the BrowserMatch feature:
http://httpd.apache.org/docs/2.2/mod/mod_auth_digest.html#msie
Further details on Digest implementation differences:
http://www.fngtps.com/2006/09/http-authentication
*/
if(authp->iestyle && ((tmp = strchr((char *)uripath, '?')) != NULL)) {
md5this = (unsigned char *)aprintf("%s:%.*s", request,
(int)(tmp - (char *)uripath), uripath);
}
else
md5this = (unsigned char *)aprintf("%s:%s", request, uripath);
if(!md5this) {
free(ha1);
return CURLE_OUT_OF_MEMORY;
}
if(d->qop && Curl_raw_equal(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_OUTPUT_DIGEST_CONV(data, md5this); /* convert on non-ASCII machines */
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_OUTPUT_DIGEST_CONV(data, md5this); /* convert on non-ASCII machines */
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="******", realm="testrealm", \
nonce="1053604145", uri="/64", response="c55f7f30d83d774a3d2dcacf725abaca"
*/
if(d->qop) {
*allocuserpwd =
aprintf( "%sAuthorization: Digest "
"username=\"%s\", "
"realm=\"%s\", "
"nonce=\"%s\", "
"uri=\"%s\", "
"cnonce=\"%s\", "
"nc=%08x, "
"qop=\"%s\", "
"response=\"%s\"",
proxy?"Proxy-":"",
userp,
d->realm,
d->nonce,
uripath, /* this is the PATH part of the URL */
d->cnonce,
d->nc,
d->qop,
request_digest);
if(Curl_raw_equal(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 {
*allocuserpwd =
aprintf( "%sAuthorization: Digest "
"username=\"%s\", "
"realm=\"%s\", "
"nonce=\"%s\", "
"uri=\"%s\", "
"response=\"%s\"",
proxy?"Proxy-":"",
userp,
d->realm,
d->nonce,
uripath, /* this is the PATH part of the URL */
request_digest);
}
if(!*allocuserpwd)
return CURLE_OUT_OF_MEMORY;
/* Add optional fields */
if(d->opaque) {
/* append opaque */
tmp = aprintf("%s, opaque=\"%s\"", *allocuserpwd, d->opaque);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
free(*allocuserpwd);
*allocuserpwd = tmp;
}
if(d->algorithm) {
/* append algorithm */
tmp = aprintf("%s, algorithm=\"%s\"", *allocuserpwd, d->algorithm);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
free(*allocuserpwd);
*allocuserpwd = tmp;
}
/* append CRLF + zero (3 bytes) to the userpwd header */
tmp = realloc(*allocuserpwd, strlen(*allocuserpwd) + 3);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
strcat(tmp, "\r\n");
*allocuserpwd = tmp;
return CURLE_OK;
}
/*
* Curl_auth_create_digest_http_message()
*
* This is used to generate a HTTP DIGEST response message ready for sending
* to the recipient.
*
* Parameters:
*
* data [in] - The session handle.
* userp [in] - The user name.
* passdwp [in] - The user's password.
* request [in] - The HTTP request.
* uripath [in] - The path of the HTTP uri.
* digest [in/out] - The digest data struct being used and modified.
* outptr [in/out] - The address where a pointer to newly allocated memory
* holding the result will be stored upon completion.
* outlen [out] - The length of the output message.
*
* Returns CURLE_OK on success.
*/
CURLcode Curl_auth_create_digest_http_message(struct Curl_easy *data,
const char *userp,
const char *passwdp,
const unsigned char *request,
const unsigned char *uripath,
struct digestdata *digest,
char **outptr, size_t *outlen)
{
CURLcode result;
unsigned char md5buf[16]; /* 16 bytes/128 bits */
unsigned char request_digest[33];
unsigned char *md5this;
unsigned char ha1[33]; /* 32 digits and 1 zero byte */
unsigned char ha2[33]; /* 32 digits and 1 zero byte */
char cnoncebuf[33];
char *cnonce = NULL;
size_t cnonce_sz = 0;
char *userp_quoted;
char *response = NULL;
char *tmp = NULL;
if(!digest->nc)
digest->nc = 1;
if(!digest->cnonce) {
snprintf(cnoncebuf, sizeof(cnoncebuf), "%08x%08x%08x%08x",
Curl_rand(data), Curl_rand(data),
Curl_rand(data), Curl_rand(data));
result = Curl_base64_encode(data, cnoncebuf, strlen(cnoncebuf),
&cnonce, &cnonce_sz);
if(result)
return result;
digest->cnonce = cnonce;
}
/*
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", userp, digest->realm, passwdp);
if(!md5this)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, md5this); /* convert on non-ASCII machines */
Curl_md5it(md5buf, md5this);
free(md5this);
auth_digest_md5_to_ascii(md5buf, ha1);
if(digest->algo == CURLDIGESTALGO_MD5SESS) {
/* nonce and cnonce are OUTSIDE the hash */
tmp = aprintf("%s:%s:%s", ha1, digest->nonce, digest->cnonce);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, tmp); /* Convert on non-ASCII machines */
Curl_md5it(md5buf, (unsigned char *) tmp);
free(tmp);
auth_digest_md5_to_ascii(md5buf, ha1);
}
/*
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(digest->qop && Curl_raw_equal(digest->qop, "auth-int")) {
/* We don't support auth-int for PUT or POST at the moment.
TODO: replace md5 of empty string with entity-body for PUT/POST */
unsigned char *md5this2 = (unsigned char *)
aprintf("%s:%s", md5this, "d41d8cd98f00b204e9800998ecf8427e");
free(md5this);
md5this = md5this2;
}
if(!md5this)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, md5this); /* convert on non-ASCII machines */
Curl_md5it(md5buf, md5this);
free(md5this);
auth_digest_md5_to_ascii(md5buf, ha2);
if(digest->qop) {
md5this = (unsigned char *) aprintf("%s:%s:%08x:%s:%s:%s",
ha1,
digest->nonce,
digest->nc,
digest->cnonce,
digest->qop,
ha2);
}
else {
md5this = (unsigned char *) aprintf("%s:%s:%s",
ha1,
digest->nonce,
ha2);
}
if(!md5this)
return CURLE_OUT_OF_MEMORY;
CURL_OUTPUT_DIGEST_CONV(data, md5this); /* convert on non-ASCII machines */
Curl_md5it(md5buf, md5this);
free(md5this);
auth_digest_md5_to_ascii(md5buf, request_digest);
/* For test case 64 (snooped from a Mozilla 1.3a request)
Authorization: Digest username="******", realm="testrealm", \
nonce="1053604145", uri="/64", response="c55f7f30d83d774a3d2dcacf725abaca"
Digest parameters are all quoted strings. Username which is provided by
the user will need double quotes and backslashes within it escaped. For
the other fields, this shouldn't be an issue. realm, nonce, and opaque
are copied as is from the server, escapes and all. cnonce is generated
with web-safe characters. uri is already percent encoded. nc is 8 hex
characters. algorithm and qop with standard values only contain web-safe
characters.
*/
userp_quoted = auth_digest_string_quoted(userp);
if(!userp_quoted)
return CURLE_OUT_OF_MEMORY;
if(digest->qop) {
response = aprintf("username=\"%s\", "
"realm=\"%s\", "
"nonce=\"%s\", "
"uri=\"%s\", "
"cnonce=\"%s\", "
"nc=%08x, "
"qop=%s, "
"response=\"%s\"",
userp_quoted,
digest->realm,
digest->nonce,
uripath,
digest->cnonce,
digest->nc,
digest->qop,
request_digest);
if(Curl_raw_equal(digest->qop, "auth"))
digest->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 {
response = aprintf("username=\"%s\", "
"realm=\"%s\", "
"nonce=\"%s\", "
"uri=\"%s\", "
"response=\"%s\"",
userp_quoted,
digest->realm,
digest->nonce,
uripath,
request_digest);
}
free(userp_quoted);
if(!response)
return CURLE_OUT_OF_MEMORY;
/* Add the optional fields */
if(digest->opaque) {
/* Append the opaque */
tmp = aprintf("%s, opaque=\"%s\"", response, digest->opaque);
free(response);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
response = tmp;
}
if(digest->algorithm) {
/* Append the algorithm */
tmp = aprintf("%s, algorithm=\"%s\"", response, digest->algorithm);
free(response);
if(!tmp)
return CURLE_OUT_OF_MEMORY;
response = tmp;
}
/* Return the output */
*outptr = response;
*outlen = strlen(response);
return CURLE_OK;
}