httpauth.c
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1 /*
2  * HTTP authentication
3  * Copyright (c) 2010 Martin Storsjo
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "httpauth.h"
23 #include "libavutil/base64.h"
24 #include "libavutil/avstring.h"
25 #include "internal.h"
26 #include "libavutil/random_seed.h"
27 #include "libavutil/md5.h"
28 #include "avformat.h"
29 #include <ctype.h>
30 
31 static void handle_basic_params(HTTPAuthState *state, const char *key,
32  int key_len, char **dest, int *dest_len)
33 {
34  if (!strncmp(key, "realm=", key_len)) {
35  *dest = state->realm;
36  *dest_len = sizeof(state->realm);
37  }
38 }
39 
40 static void handle_digest_params(HTTPAuthState *state, const char *key,
41  int key_len, char **dest, int *dest_len)
42 {
43  DigestParams *digest = &state->digest_params;
44 
45  if (!strncmp(key, "realm=", key_len)) {
46  *dest = state->realm;
47  *dest_len = sizeof(state->realm);
48  } else if (!strncmp(key, "nonce=", key_len)) {
49  *dest = digest->nonce;
50  *dest_len = sizeof(digest->nonce);
51  } else if (!strncmp(key, "opaque=", key_len)) {
52  *dest = digest->opaque;
53  *dest_len = sizeof(digest->opaque);
54  } else if (!strncmp(key, "algorithm=", key_len)) {
55  *dest = digest->algorithm;
56  *dest_len = sizeof(digest->algorithm);
57  } else if (!strncmp(key, "qop=", key_len)) {
58  *dest = digest->qop;
59  *dest_len = sizeof(digest->qop);
60  }
61 }
62 
63 static void handle_digest_update(HTTPAuthState *state, const char *key,
64  int key_len, char **dest, int *dest_len)
65 {
66  DigestParams *digest = &state->digest_params;
67 
68  if (!strncmp(key, "nextnonce=", key_len)) {
69  *dest = digest->nonce;
70  *dest_len = sizeof(digest->nonce);
71  }
72 }
73 
74 static void choose_qop(char *qop, int size)
75 {
76  char *ptr = strstr(qop, "auth");
77  char *end = ptr + strlen("auth");
78 
79  if (ptr && (!*end || isspace(*end) || *end == ',') &&
80  (ptr == qop || isspace(ptr[-1]) || ptr[-1] == ',')) {
81  av_strlcpy(qop, "auth", size);
82  } else {
83  qop[0] = 0;
84  }
85 }
86 
88  const char *value)
89 {
90  if (!strcmp(key, "WWW-Authenticate") || !strcmp(key, "Proxy-Authenticate")) {
91  const char *p;
92  if (av_stristart(value, "Basic ", &p) &&
93  state->auth_type <= HTTP_AUTH_BASIC) {
94  state->auth_type = HTTP_AUTH_BASIC;
95  state->realm[0] = 0;
97  state);
98  } else if (av_stristart(value, "Digest ", &p) &&
99  state->auth_type <= HTTP_AUTH_DIGEST) {
100  state->auth_type = HTTP_AUTH_DIGEST;
101  memset(&state->digest_params, 0, sizeof(DigestParams));
102  state->realm[0] = 0;
104  state);
106  sizeof(state->digest_params.qop));
107  }
108  } else if (!strcmp(key, "Authentication-Info")) {
110  state);
111  }
112 }
113 
114 
115 static void update_md5_strings(struct AVMD5 *md5ctx, ...)
116 {
117  va_list vl;
118 
119  va_start(vl, md5ctx);
120  while (1) {
121  const char* str = va_arg(vl, const char*);
122  if (!str)
123  break;
124  av_md5_update(md5ctx, str, strlen(str));
125  }
126  va_end(vl);
127 }
128 
129 /* Generate a digest reply, according to RFC 2617. */
130 static char *make_digest_auth(HTTPAuthState *state, const char *username,
131  const char *password, const char *uri,
132  const char *method)
133 {
134  DigestParams *digest = &state->digest_params;
135  int len;
136  uint32_t cnonce_buf[2];
137  char cnonce[17];
138  char nc[9];
139  int i;
140  char A1hash[33], A2hash[33], response[33];
141  struct AVMD5 *md5ctx;
142  uint8_t hash[16];
143  char *authstr;
144 
145  digest->nc++;
146  snprintf(nc, sizeof(nc), "%08x", digest->nc);
147 
148  /* Generate a client nonce. */
149  for (i = 0; i < 2; i++)
150  cnonce_buf[i] = av_get_random_seed();
151  ff_data_to_hex(cnonce, (const uint8_t*) cnonce_buf, sizeof(cnonce_buf), 1);
152  cnonce[2*sizeof(cnonce_buf)] = 0;
153 
154  md5ctx = av_malloc(av_md5_size);
155  if (!md5ctx)
156  return NULL;
157 
158  av_md5_init(md5ctx);
159  update_md5_strings(md5ctx, username, ":", state->realm, ":", password, NULL);
160  av_md5_final(md5ctx, hash);
161  ff_data_to_hex(A1hash, hash, 16, 1);
162  A1hash[32] = 0;
163 
164  if (!strcmp(digest->algorithm, "") || !strcmp(digest->algorithm, "MD5")) {
165  } else if (!strcmp(digest->algorithm, "MD5-sess")) {
166  av_md5_init(md5ctx);
167  update_md5_strings(md5ctx, A1hash, ":", digest->nonce, ":", cnonce, NULL);
168  av_md5_final(md5ctx, hash);
169  ff_data_to_hex(A1hash, hash, 16, 1);
170  A1hash[32] = 0;
171  } else {
172  /* Unsupported algorithm */
173  av_free(md5ctx);
174  return NULL;
175  }
176 
177  av_md5_init(md5ctx);
178  update_md5_strings(md5ctx, method, ":", uri, NULL);
179  av_md5_final(md5ctx, hash);
180  ff_data_to_hex(A2hash, hash, 16, 1);
181  A2hash[32] = 0;
182 
183  av_md5_init(md5ctx);
184  update_md5_strings(md5ctx, A1hash, ":", digest->nonce, NULL);
185  if (!strcmp(digest->qop, "auth") || !strcmp(digest->qop, "auth-int")) {
186  update_md5_strings(md5ctx, ":", nc, ":", cnonce, ":", digest->qop, NULL);
187  }
188  update_md5_strings(md5ctx, ":", A2hash, NULL);
189  av_md5_final(md5ctx, hash);
190  ff_data_to_hex(response, hash, 16, 1);
191  response[32] = 0;
192 
193  av_free(md5ctx);
194 
195  if (!strcmp(digest->qop, "") || !strcmp(digest->qop, "auth")) {
196  } else if (!strcmp(digest->qop, "auth-int")) {
197  /* qop=auth-int not supported */
198  return NULL;
199  } else {
200  /* Unsupported qop value. */
201  return NULL;
202  }
203 
204  len = strlen(username) + strlen(state->realm) + strlen(digest->nonce) +
205  strlen(uri) + strlen(response) + strlen(digest->algorithm) +
206  strlen(digest->opaque) + strlen(digest->qop) + strlen(cnonce) +
207  strlen(nc) + 150;
208 
209  authstr = av_malloc(len);
210  if (!authstr)
211  return NULL;
212  snprintf(authstr, len, "Authorization: Digest ");
213 
214  /* TODO: Escape the quoted strings properly. */
215  av_strlcatf(authstr, len, "username=\"%s\"", username);
216  av_strlcatf(authstr, len, ",realm=\"%s\"", state->realm);
217  av_strlcatf(authstr, len, ",nonce=\"%s\"", digest->nonce);
218  av_strlcatf(authstr, len, ",uri=\"%s\"", uri);
219  av_strlcatf(authstr, len, ",response=\"%s\"", response);
220  if (digest->algorithm[0])
221  av_strlcatf(authstr, len, ",algorithm=%s", digest->algorithm);
222  if (digest->opaque[0])
223  av_strlcatf(authstr, len, ",opaque=\"%s\"", digest->opaque);
224  if (digest->qop[0]) {
225  av_strlcatf(authstr, len, ",qop=\"%s\"", digest->qop);
226  av_strlcatf(authstr, len, ",cnonce=\"%s\"", cnonce);
227  av_strlcatf(authstr, len, ",nc=%s", nc);
228  }
229 
230  av_strlcatf(authstr, len, "\r\n");
231 
232  return authstr;
233 }
234 
236  const char *path, const char *method)
237 {
238  char *authstr = NULL;
239 
240  if (!auth || !strchr(auth, ':'))
241  return NULL;
242 
243  if (state->auth_type == HTTP_AUTH_BASIC) {
244  int auth_b64_len = AV_BASE64_SIZE(strlen(auth));
245  int len = auth_b64_len + 30;
246  char *ptr;
247  authstr = av_malloc(len);
248  if (!authstr)
249  return NULL;
250  snprintf(authstr, len, "Authorization: Basic ");
251  ptr = authstr + strlen(authstr);
252  av_base64_encode(ptr, auth_b64_len, auth, strlen(auth));
253  av_strlcat(ptr, "\r\n", len - (ptr - authstr));
254  } else if (state->auth_type == HTTP_AUTH_DIGEST) {
255  char *username = av_strdup(auth), *password;
256 
257  if (!username)
258  return NULL;
259 
260  if ((password = strchr(username, ':'))) {
261  *password++ = 0;
262  authstr = make_digest_auth(state, username, password, path, method);
263  }
264  av_free(username);
265  }
266  return authstr;
267 }
268 
int size
void(* ff_parse_key_val_cb)(void *context, const char *key, int key_len, char **dest, int *dest_len)
Callback function type for ff_parse_key_value.
Definition: internal.h:183
char algorithm[10]
Server specified digest algorithm.
Definition: httpauth.h:37
static int hash(int head, const int add)
Hash function adding character.
Definition: lzwenc.c:74
static void handle_basic_params(HTTPAuthState *state, const char *key, int key_len, char **dest, int *dest_len)
Definition: httpauth.c:31
HTTP Authentication state structure.
Definition: httpauth.h:52
int av_stristart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str independent of case.
Definition: avstring.c:40
char opaque[300]
A server-specified string that should be included in authentication responses, not included in the ac...
Definition: httpauth.h:41
const int av_md5_size
Definition: md5.c:44
HTTP 1.0 Basic auth from RFC 1945 (also in RFC 2617)
Definition: httpauth.h:30
Definition: md5.c:38
static void choose_qop(char *qop, int size)
Definition: httpauth.c:74
void av_md5_update(AVMD5 *ctx, const uint8_t *src, const int len)
Definition: md5.c:136
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:137
char * av_base64_encode(char *out, int out_size, const uint8_t *in, int in_size)
Encode data to base64 and null-terminate.
Definition: base64.c:72
size_t av_strlcpy(char *dst, const char *src, size_t size)
Copy the string src to dst, but no more than size - 1 bytes, and null-terminate dst.
Definition: avstring.c:64
#define AV_BASE64_SIZE(x)
Calculate the output size needed to base64-encode x bytes.
Definition: base64.h:59
static char * make_digest_auth(HTTPAuthState *state, const char *username, const char *password, const char *uri, const char *method)
Definition: httpauth.c:130
static void handle_digest_params(HTTPAuthState *state, const char *key, int key_len, char **dest, int *dest_len)
Definition: httpauth.c:40
NULL
Definition: eval.c:50
char * av_strdup(const char *s)
Duplicate the string s.
Definition: mem.c:162
char realm[200]
Authentication realm.
Definition: httpauth.h:60
void av_md5_init(AVMD5 *ctx)
Definition: md5.c:126
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:64
HTTP 1.1 Digest auth from RFC 2617.
Definition: httpauth.h:32
char qop[30]
Quality of protection, containing the one that we've chosen to use, from the alternatives that the se...
Definition: httpauth.h:38
size_t av_strlcatf(char *dst, size_t size, const char *fmt,...)
Definition: avstring.c:82
void av_md5_final(AVMD5 *ctx, uint8_t *dst)
Definition: md5.c:152
char * ff_http_auth_create_response(HTTPAuthState *state, const char *auth, const char *path, const char *method)
Definition: httpauth.c:235
size_t av_strlcat(char *dst, const char *src, size_t size)
Append the string src to the string dst, but to a total length of no more than size - 1 bytes...
Definition: avstring.c:74
static uint32_t state
Definition: trasher.c:25
void ff_parse_key_value(const char *str, ff_parse_key_val_cb callback_get_buf, void *context)
Parse a string with comma-separated key=value pairs.
Definition: utils.c:3909
Main libavformat public API header.
void ff_http_auth_handle_header(HTTPAuthState *state, const char *key, const char *value)
Definition: httpauth.c:87
static void handle_digest_update(HTTPAuthState *state, const char *key, int key_len, char **dest, int *dest_len)
Definition: httpauth.c:63
int len
char nonce[300]
Server specified nonce.
Definition: httpauth.h:36
DigestParams digest_params
The parameters specifiec to digest authentication.
Definition: httpauth.h:64
HTTPAuthType auth_type
The currently chosen auth type.
Definition: httpauth.h:56
int nc
Nonce count, the number of earlier replies where this particular nonce has been used.
Definition: httpauth.h:44
uint32_t av_get_random_seed(void)
Get random data.
Definition: random_seed.c:73
char * ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase)
Definition: utils.c:3771
static void update_md5_strings(struct AVMD5 *md5ctx,...)
Definition: httpauth.c:115