| 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 (!strcmp(key, "WWW-Authenticate") || !strcmp(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 (!strcmp(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 | cnonce[2*sizeof(cnonce_buf)] = 0; |
| 160 | |
| 161 | md5ctx = av_md5_alloc(); |
| 162 | if (!md5ctx) |
| 163 | return NULL; |
| 164 | |
| 165 | av_md5_init(md5ctx); |
| 166 | update_md5_strings(md5ctx, username, ":", state->realm, ":", password, NULL); |
| 167 | av_md5_final(md5ctx, hash); |
| 168 | ff_data_to_hex(A1hash, hash, 16, 1); |
| 169 | A1hash[32] = 0; |
| 170 | |
| 171 | if (!strcmp(digest->algorithm, "") || !strcmp(digest->algorithm, "MD5")) { |
| 172 | } else if (!strcmp(digest->algorithm, "MD5-sess")) { |
| 173 | av_md5_init(md5ctx); |
| 174 | update_md5_strings(md5ctx, A1hash, ":", digest->nonce, ":", cnonce, NULL); |
| 175 | av_md5_final(md5ctx, hash); |
| 176 | ff_data_to_hex(A1hash, hash, 16, 1); |
| 177 | A1hash[32] = 0; |
| 178 | } else { |
| 179 | /* Unsupported algorithm */ |
| 180 | av_free(md5ctx); |
| 181 | return NULL; |
| 182 | } |
| 183 | |
| 184 | av_md5_init(md5ctx); |
| 185 | update_md5_strings(md5ctx, method, ":", uri, NULL); |
| 186 | av_md5_final(md5ctx, hash); |
| 187 | ff_data_to_hex(A2hash, hash, 16, 1); |
| 188 | A2hash[32] = 0; |
| 189 | |
| 190 | av_md5_init(md5ctx); |
| 191 | update_md5_strings(md5ctx, A1hash, ":", digest->nonce, NULL); |
| 192 | if (!strcmp(digest->qop, "auth") || !strcmp(digest->qop, "auth-int")) { |
| 193 | update_md5_strings(md5ctx, ":", nc, ":", cnonce, ":", digest->qop, NULL); |
| 194 | } |
| 195 | update_md5_strings(md5ctx, ":", A2hash, NULL); |
| 196 | av_md5_final(md5ctx, hash); |
| 197 | ff_data_to_hex(response, hash, 16, 1); |
| 198 | response[32] = 0; |
| 199 | |
| 200 | av_free(md5ctx); |
| 201 | |
| 202 | if (!strcmp(digest->qop, "") || !strcmp(digest->qop, "auth")) { |
| 203 | } else if (!strcmp(digest->qop, "auth-int")) { |
| 204 | /* qop=auth-int not supported */ |
| 205 | return NULL; |
| 206 | } else { |
| 207 | /* Unsupported qop value. */ |
| 208 | return NULL; |
| 209 | } |
| 210 | |
| 211 | len = strlen(username) + strlen(state->realm) + strlen(digest->nonce) + |
| 212 | strlen(uri) + strlen(response) + strlen(digest->algorithm) + |
| 213 | strlen(digest->opaque) + strlen(digest->qop) + strlen(cnonce) + |
| 214 | strlen(nc) + 150; |
| 215 | |
| 216 | authstr = av_malloc(len); |
| 217 | if (!authstr) |
| 218 | return NULL; |
| 219 | snprintf(authstr, len, "Authorization: Digest "); |
| 220 | |
| 221 | /* TODO: Escape the quoted strings properly. */ |
| 222 | av_strlcatf(authstr, len, "username=\"%s\"", username); |
| 223 | av_strlcatf(authstr, len, ",realm=\"%s\"", state->realm); |
| 224 | av_strlcatf(authstr, len, ",nonce=\"%s\"", digest->nonce); |
| 225 | av_strlcatf(authstr, len, ",uri=\"%s\"", uri); |
| 226 | av_strlcatf(authstr, len, ",response=\"%s\"", response); |
| 227 | |
| 228 | // we are violating the RFC and use "" because all others seem to do that too. |
| 229 | if (digest->algorithm[0]) |
| 230 | av_strlcatf(authstr, len, ",algorithm=\"%s\"", digest->algorithm); |
| 231 | |
| 232 | if (digest->opaque[0]) |
| 233 | av_strlcatf(authstr, len, ",opaque=\"%s\"", digest->opaque); |
| 234 | if (digest->qop[0]) { |
| 235 | av_strlcatf(authstr, len, ",qop=\"%s\"", digest->qop); |
| 236 | av_strlcatf(authstr, len, ",cnonce=\"%s\"", cnonce); |
| 237 | av_strlcatf(authstr, len, ",nc=%s", nc); |
| 238 | } |
| 239 | |
| 240 | av_strlcatf(authstr, len, "\r\n"); |
| 241 | |
| 242 | return authstr; |
| 243 | } |
| 244 | |
| 245 | char *ff_http_auth_create_response(HTTPAuthState *state, const char *auth, |
| 246 | const char *path, const char *method) |
| 247 | { |
| 248 | char *authstr = NULL; |
| 249 | |
| 250 | /* Clear the stale flag, we assume the auth is ok now. It is reset |
| 251 | * by the server headers if there's a new issue. */ |
| 252 | state->stale = 0; |
| 253 | if (!auth || !strchr(auth, ':')) |
| 254 | return NULL; |
| 255 | |
| 256 | if (state->auth_type == HTTP_AUTH_BASIC) { |
| 257 | int auth_b64_len, len; |
| 258 | char *ptr, *decoded_auth = ff_urldecode(auth); |
| 259 | |
| 260 | if (!decoded_auth) |
| 261 | return NULL; |
| 262 | |
| 263 | auth_b64_len = AV_BASE64_SIZE(strlen(decoded_auth)); |
| 264 | len = auth_b64_len + 30; |
| 265 | |
| 266 | authstr = av_malloc(len); |
| 267 | if (!authstr) { |
| 268 | av_free(decoded_auth); |
| 269 | return NULL; |
| 270 | } |
| 271 | |
| 272 | snprintf(authstr, len, "Authorization: Basic "); |
| 273 | ptr = authstr + strlen(authstr); |
| 274 | av_base64_encode(ptr, auth_b64_len, decoded_auth, strlen(decoded_auth)); |
| 275 | av_strlcat(ptr, "\r\n", len - (ptr - authstr)); |
| 276 | av_free(decoded_auth); |
| 277 | } else if (state->auth_type == HTTP_AUTH_DIGEST) { |
| 278 | char *username = ff_urldecode(auth), *password; |
| 279 | |
| 280 | if (!username) |
| 281 | return NULL; |
| 282 | |
| 283 | if ((password = strchr(username, ':'))) { |
| 284 | *password++ = 0; |
| 285 | authstr = make_digest_auth(state, username, password, path, method); |
| 286 | } |
| 287 | av_free(username); |
| 288 | } |
| 289 | return authstr; |
| 290 | } |