FFmpeg
httpauth.c
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1 /*
2  * HTTP authentication
3  * Copyright (c) 2010 Martin Storsjo
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 "urldecode.h"
29 #include "avformat.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  } else if (!strncmp(key, "stale=", key_len)) {
61  *dest = digest->stale;
62  *dest_len = sizeof(digest->stale);
63  }
64 }
65 
66 static void handle_digest_update(HTTPAuthState *state, const char *key,
67  int key_len, char **dest, int *dest_len)
68 {
69  DigestParams *digest = &state->digest_params;
70 
71  if (!strncmp(key, "nextnonce=", key_len)) {
72  *dest = digest->nonce;
73  *dest_len = sizeof(digest->nonce);
74  }
75 }
76 
77 static void choose_qop(char *qop, int size)
78 {
79  char *ptr = strstr(qop, "auth");
80  char *end = ptr + strlen("auth");
81 
82  if (ptr && (!*end || av_isspace(*end) || *end == ',') &&
83  (ptr == qop || av_isspace(ptr[-1]) || ptr[-1] == ',')) {
84  av_strlcpy(qop, "auth", size);
85  } else {
86  qop[0] = 0;
87  }
88 }
89 
90 void ff_http_auth_handle_header(HTTPAuthState *state, const char *key,
91  const char *value)
92 {
93  if (!av_strcasecmp(key, "WWW-Authenticate") || !av_strcasecmp(key, "Proxy-Authenticate")) {
94  const char *p;
95  if (av_stristart(value, "Basic ", &p) &&
96  state->auth_type <= HTTP_AUTH_BASIC) {
97  state->auth_type = HTTP_AUTH_BASIC;
98  state->realm[0] = 0;
99  state->stale = 0;
100  ff_parse_key_value(p, (ff_parse_key_val_cb) handle_basic_params,
101  state);
102  } else if (av_stristart(value, "Digest ", &p) &&
103  state->auth_type <= HTTP_AUTH_DIGEST) {
104  state->auth_type = HTTP_AUTH_DIGEST;
105  memset(&state->digest_params, 0, sizeof(DigestParams));
106  state->realm[0] = 0;
107  state->stale = 0;
108  ff_parse_key_value(p, (ff_parse_key_val_cb) handle_digest_params,
109  state);
110  choose_qop(state->digest_params.qop,
111  sizeof(state->digest_params.qop));
112  if (!av_strcasecmp(state->digest_params.stale, "true"))
113  state->stale = 1;
114  }
115  } else if (!av_strcasecmp(key, "Authentication-Info")) {
116  ff_parse_key_value(value, (ff_parse_key_val_cb) handle_digest_update,
117  state);
118  }
119 }
120 
121 
122 static void update_md5_strings(struct AVMD5 *md5ctx, ...)
123 {
124  va_list vl;
125 
126  va_start(vl, md5ctx);
127  while (1) {
128  const char* str = va_arg(vl, const char*);
129  if (!str)
130  break;
131  av_md5_update(md5ctx, str, strlen(str));
132  }
133  va_end(vl);
134 }
135 
136 /* Generate a digest reply, according to RFC 2617. */
137 static char *make_digest_auth(HTTPAuthState *state, const char *username,
138  const char *password, const char *uri,
139  const char *method)
140 {
141  DigestParams *digest = &state->digest_params;
142  int len;
143  uint32_t cnonce_buf[2];
144  char cnonce[17];
145  char nc[9];
146  int i;
147  char A1hash[33], A2hash[33], response[33];
148  struct AVMD5 *md5ctx;
149  uint8_t hash[16];
150  char *authstr;
151 
152  digest->nc++;
153  snprintf(nc, sizeof(nc), "%08x", digest->nc);
154 
155  /* Generate a client nonce. */
156  for (i = 0; i < 2; i++)
157  cnonce_buf[i] = av_get_random_seed();
158  ff_data_to_hex(cnonce, (const uint8_t*) cnonce_buf, sizeof(cnonce_buf), 1);
159 
160  md5ctx = av_md5_alloc();
161  if (!md5ctx)
162  return NULL;
163 
164  av_md5_init(md5ctx);
165  update_md5_strings(md5ctx, username, ":", state->realm, ":", password, NULL);
166  av_md5_final(md5ctx, hash);
167  ff_data_to_hex(A1hash, hash, 16, 1);
168 
169  if (!strcmp(digest->algorithm, "") || !strcmp(digest->algorithm, "MD5")) {
170  } else if (!strcmp(digest->algorithm, "MD5-sess")) {
171  av_md5_init(md5ctx);
172  update_md5_strings(md5ctx, A1hash, ":", digest->nonce, ":", cnonce, NULL);
173  av_md5_final(md5ctx, hash);
174  ff_data_to_hex(A1hash, hash, 16, 1);
175  } else {
176  /* Unsupported algorithm */
177  av_free(md5ctx);
178  return NULL;
179  }
180 
181  av_md5_init(md5ctx);
182  update_md5_strings(md5ctx, method, ":", uri, NULL);
183  av_md5_final(md5ctx, hash);
184  ff_data_to_hex(A2hash, hash, 16, 1);
185 
186  av_md5_init(md5ctx);
187  update_md5_strings(md5ctx, A1hash, ":", digest->nonce, NULL);
188  if (!strcmp(digest->qop, "auth") || !strcmp(digest->qop, "auth-int")) {
189  update_md5_strings(md5ctx, ":", nc, ":", cnonce, ":", digest->qop, NULL);
190  }
191  update_md5_strings(md5ctx, ":", A2hash, NULL);
192  av_md5_final(md5ctx, hash);
193  ff_data_to_hex(response, hash, 16, 1);
194 
195  av_free(md5ctx);
196 
197  if (!strcmp(digest->qop, "") || !strcmp(digest->qop, "auth")) {
198  } else if (!strcmp(digest->qop, "auth-int")) {
199  /* qop=auth-int not supported */
200  return NULL;
201  } else {
202  /* Unsupported qop value. */
203  return NULL;
204  }
205 
206  len = strlen(username) + strlen(state->realm) + strlen(digest->nonce) +
207  strlen(uri) + strlen(response) + strlen(digest->algorithm) +
208  strlen(digest->opaque) + strlen(digest->qop) + strlen(cnonce) +
209  strlen(nc) + 150;
210 
211  authstr = av_malloc(len);
212  if (!authstr)
213  return NULL;
214  snprintf(authstr, len, "Authorization: Digest ");
215 
216  /* TODO: Escape the quoted strings properly. */
217  av_strlcatf(authstr, len, "username=\"%s\"", username);
218  av_strlcatf(authstr, len, ", realm=\"%s\"", state->realm);
219  av_strlcatf(authstr, len, ", nonce=\"%s\"", digest->nonce);
220  av_strlcatf(authstr, len, ", uri=\"%s\"", uri);
221  av_strlcatf(authstr, len, ", response=\"%s\"", response);
222 
223  // we are violating the RFC and use "" because all others seem to do that too.
224  if (digest->algorithm[0])
225  av_strlcatf(authstr, len, ", algorithm=\"%s\"", digest->algorithm);
226 
227  if (digest->opaque[0])
228  av_strlcatf(authstr, len, ", opaque=\"%s\"", digest->opaque);
229  if (digest->qop[0]) {
230  av_strlcatf(authstr, len, ", qop=\"%s\"", digest->qop);
231  av_strlcatf(authstr, len, ", cnonce=\"%s\"", cnonce);
232  av_strlcatf(authstr, len, ", nc=%s", nc);
233  }
234 
235  av_strlcatf(authstr, len, "\r\n");
236 
237  return authstr;
238 }
239 
240 char *ff_http_auth_create_response(HTTPAuthState *state, const char *auth,
241  const char *path, const char *method)
242 {
243  char *authstr = NULL;
244 
245  /* Clear the stale flag, we assume the auth is ok now. It is reset
246  * by the server headers if there's a new issue. */
247  state->stale = 0;
248  if (!auth || !strchr(auth, ':'))
249  return NULL;
250 
251  if (state->auth_type == HTTP_AUTH_BASIC) {
252  int auth_b64_len, len;
253  char *ptr, *decoded_auth = ff_urldecode(auth, 0);
254 
255  if (!decoded_auth)
256  return NULL;
257 
258  auth_b64_len = AV_BASE64_SIZE(strlen(decoded_auth));
259  len = auth_b64_len + 30;
260 
261  authstr = av_malloc(len);
262  if (!authstr) {
263  av_free(decoded_auth);
264  return NULL;
265  }
266 
267  snprintf(authstr, len, "Authorization: Basic ");
268  ptr = authstr + strlen(authstr);
269  av_base64_encode(ptr, auth_b64_len, decoded_auth, strlen(decoded_auth));
270  av_strlcat(ptr, "\r\n", len - (ptr - authstr));
271  av_free(decoded_auth);
272  } else if (state->auth_type == HTTP_AUTH_DIGEST) {
273  char *username = ff_urldecode(auth, 0), *password;
274 
275  if (!username)
276  return NULL;
277 
278  if ((password = strchr(username, ':'))) {
279  *password++ = 0;
280  authstr = make_digest_auth(state, username, password, path, method);
281  }
282  av_free(username);
283  }
284  return authstr;
285 }
HTTP_AUTH_BASIC
@ HTTP_AUTH_BASIC
HTTP 1.0 Basic auth from RFC 1945 (also in RFC 2617)
Definition: httpauth.h:30
av_strcasecmp
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:215
av_isspace
static av_const int av_isspace(int c)
Locale-independent conversion of ASCII isspace.
Definition: avstring.h:227
make_digest_auth
static char * make_digest_auth(HTTPAuthState *state, const char *username, const char *password, const char *uri, const char *method)
Definition: httpauth.c:137
update_md5_strings
static void update_md5_strings(struct AVMD5 *md5ctx,...)
Definition: httpauth.c:122
ff_http_auth_create_response
char * ff_http_auth_create_response(HTTPAuthState *state, const char *auth, const char *path, const char *method)
Definition: httpauth.c:240
hash
uint8_t hash[HASH_SIZE]
Definition: movenc.c:57
av_strlcatf
size_t av_strlcatf(char *dst, size_t size, const char *fmt,...)
Definition: avstring.c:101
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
av_get_random_seed
uint32_t av_get_random_seed(void)
Get a seed to use in conjunction with random functions.
Definition: random_seed.c:120
ff_urldecode
char * ff_urldecode(const char *url, int decode_plus_sign)
Decodes an URL from its percent-encoded form back into normal representation.
Definition: urldecode.c:35
ff_data_to_hex
char * ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase)
Write hexadecimal string corresponding to given binary data.
Definition: utils.c:1147
AVMD5
Definition: md5.c:40
DigestParams::qop
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
HTTP_AUTH_DIGEST
@ HTTP_AUTH_DIGEST
HTTP 1.1 Digest auth from RFC 2617.
Definition: httpauth.h:32
av_stristart
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:45
key
const char * key
Definition: hwcontext_opencl.c:168
ff_http_auth_handle_header
void ff_http_auth_handle_header(HTTPAuthState *state, const char *key, const char *value)
Definition: httpauth.c:90
internal.h
handle_digest_params
static void handle_digest_params(HTTPAuthState *state, const char *key, int key_len, char **dest, int *dest_len)
Definition: httpauth.c:40
NULL
#define NULL
Definition: coverity.c:32
DigestParams::nonce
char nonce[300]
Server specified nonce.
Definition: httpauth.h:36
choose_qop
static void choose_qop(char *qop, int size)
Definition: httpauth.c:77
base64.h
HTTPAuthState
HTTP Authentication state structure.
Definition: httpauth.h:55
state
static struct @320 state
DigestParams::stale
char stale[10]
The server indicated that the auth was ok, but needs to be redone with a new, non-stale nonce.
Definition: httpauth.h:44
size
int size
Definition: twinvq_data.h:10344
handle_digest_update
static void handle_digest_update(HTTPAuthState *state, const char *key, int key_len, char **dest, int *dest_len)
Definition: httpauth.c:66
av_md5_init
void av_md5_init(AVMD5 *ctx)
Initialize MD5 hashing.
Definition: md5.c:141
httpauth.h
AV_BASE64_SIZE
#define AV_BASE64_SIZE(x)
Calculate the output size needed to base64-encode x bytes to a null-terminated string.
Definition: base64.h:66
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
handle_basic_params
static void handle_basic_params(HTTPAuthState *state, const char *key, int key_len, char **dest, int *dest_len)
Definition: httpauth.c:31
DigestParams::opaque
char opaque[300]
A server-specified string that should be included in authentication responses, not included in the ac...
Definition: httpauth.h:41
md5.h
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
DigestParams
Definition: httpauth.h:35
len
int len
Definition: vorbis_enc_data.h:426
av_md5_final
void av_md5_final(AVMD5 *ctx, uint8_t *dst)
Finish hashing and output digest value.
Definition: md5.c:186
av_strlcat
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:93
avformat.h
DigestParams::nc
int nc
Nonce count, the number of earlier replies where this particular nonce has been used.
Definition: httpauth.h:47
random_seed.h
urldecode.h
av_md5_alloc
struct AVMD5 * av_md5_alloc(void)
Allocate an AVMD5 context.
Definition: md5.c:48
ff_parse_key_val_cb
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:614
av_base64_encode
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:143
av_md5_update
void av_md5_update(AVMD5 *ctx, const uint8_t *src, size_t len)
Update hash value.
Definition: md5.c:151
DigestParams::algorithm
char algorithm[10]
Server specified digest algorithm.
Definition: httpauth.h:37
av_free
#define av_free(p)
Definition: tableprint_vlc.h:34
convert_header.str
string str
Definition: convert_header.py:20
av_strlcpy
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:83
avstring.h
snprintf
#define snprintf
Definition: snprintf.h:34
ff_parse_key_value
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:1222
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