1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2021, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * RFC2195 CRAM-MD5 authentication
22 *
23 ***************************************************************************/
24
25 #include "curl_setup.h"
26
27 #if !defined(CURL_DISABLE_CRYPTO_AUTH)
28
29 #include <curl/curl.h>
30 #include "urldata.h"
31
32 #include "vauth/vauth.h"
33 #include "curl_hmac.h"
34 #include "curl_md5.h"
35 #include "warnless.h"
36 #include "curl_printf.h"
37
38 /* The last #include files should be: */
39 #include "curl_memory.h"
40 #include "memdebug.h"
41
42
43 /*
44 * Curl_auth_create_cram_md5_message()
45 *
46 * This is used to generate a CRAM-MD5 response message ready for sending to
47 * the recipient.
48 *
49 * Parameters:
50 *
51 * chlg [in] - The challenge.
52 * userp [in] - The user name.
53 * passwdp [in] - The user's password.
54 * out [out] - The result storage.
55 *
56 * Returns CURLE_OK on success.
57 */
Curl_auth_create_cram_md5_message(const struct bufref * chlg,const char * userp,const char * passwdp,struct bufref * out)58 CURLcode Curl_auth_create_cram_md5_message(const struct bufref *chlg,
59 const char *userp,
60 const char *passwdp,
61 struct bufref *out)
62 {
63 struct HMAC_context *ctxt;
64 unsigned char digest[MD5_DIGEST_LEN];
65 char *response;
66
67 /* Compute the digest using the password as the key */
68 ctxt = Curl_HMAC_init(Curl_HMAC_MD5,
69 (const unsigned char *) passwdp,
70 curlx_uztoui(strlen(passwdp)));
71 if(!ctxt)
72 return CURLE_OUT_OF_MEMORY;
73
74 /* Update the digest with the given challenge */
75 if(Curl_bufref_len(chlg))
76 Curl_HMAC_update(ctxt, Curl_bufref_ptr(chlg),
77 curlx_uztoui(Curl_bufref_len(chlg)));
78
79 /* Finalise the digest */
80 Curl_HMAC_final(ctxt, digest);
81
82 /* Generate the response */
83 response = aprintf(
84 "%s %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
85 userp, digest[0], digest[1], digest[2], digest[3], digest[4],
86 digest[5], digest[6], digest[7], digest[8], digest[9], digest[10],
87 digest[11], digest[12], digest[13], digest[14], digest[15]);
88 if(!response)
89 return CURLE_OUT_OF_MEMORY;
90
91 Curl_bufref_set(out, response, strlen(response), curl_free);
92 return CURLE_OK;
93 }
94
95 #endif /* !CURL_DISABLE_CRYPTO_AUTH */
96