Split out http authentication handling into a separate file

This prepares for adding support for more authentication methods

Originally committed as revision 22660 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/Makefile

@@ -272,7 +272,7 @@ OBJS+= avio.o aviobuf.o
 
 OBJS-$(CONFIG_FILE_PROTOCOL)             += file.o
 OBJS-$(CONFIG_GOPHER_PROTOCOL)           += gopher.o
-OBJS-$(CONFIG_HTTP_PROTOCOL)             += http.o
+OBJS-$(CONFIG_HTTP_PROTOCOL)             += http.o httpauth.o
 OBJS-$(CONFIG_PIPE_PROTOCOL)             += file.o
 OBJS-$(CONFIG_RTMP_PROTOCOL)             += rtmpproto.o rtmppkt.o
 OBJS-$(CONFIG_RTP_PROTOCOL)              += rtpproto.o

libavformat/http.c

@@ -19,7 +19,6 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "libavutil/base64.h"
 #include "libavutil/avstring.h"
 #include "avformat.h"
 #include <unistd.h>
@@ -27,6 +26,7 @@
 #include "internal.h"
 #include "network.h"
 #include "os_support.h"
+#include "httpauth.h"
 
 /* XXX: POST protocol is not completely implemented because ffmpeg uses
    only a subset of it. */
@@ -44,6 +44,7 @@ typedef struct {
     int64_t chunksize;      /**< Used if "Transfer-Encoding: chunked" otherwise -1. */
     int64_t off, filesize;
     char location[URL_SIZE];
+    HTTPAuthState auth_state;
 } HTTPContext;
 
 static int http_connect(URLContext *h, const char *path, const char *hoststr,
@@ -60,6 +61,7 @@ static int http_open_cnx(URLContext *h)
     char path1[1024];
     char buf[1024];
     int port, use_proxy, err, location_changed = 0, redirects = 0;
+    HTTPAuthType cur_auth_type;
     HTTPContext *s = h->priv_data;
     URLContext *hd = NULL;
 
@@ -93,8 +95,16 @@ static int http_open_cnx(URLContext *h)
         goto fail;
 
     s->hd = hd;
+    cur_auth_type = s->auth_state.auth_type;
     if (http_connect(h, path, hoststr, auth, &location_changed) < 0)
         goto fail;
+    if (s->http_code == 401) {
+        if (cur_auth_type == HTTP_AUTH_NONE && s->auth_state.auth_type != HTTP_AUTH_NONE) {
+            url_close(hd);
+            goto redo;
+        } else
+            goto fail;
+    }
     if ((s->http_code == 302 || s->http_code == 303) && location_changed == 1) {
         /* url moved, get next */
         url_close(hd);
@@ -125,6 +135,7 @@ static int http_open(URLContext *h, const char *uri, int flags)
     s->filesize = -1;
     s->chunksize = -1;
     s->off = 0;
+    memset(&s->auth_state, 0, sizeof(s->auth_state));
     av_strlcpy(s->location, uri, URL_SIZE);
 
     ret = http_open_cnx(h);
@@ -193,8 +204,9 @@ static int process_line(URLContext *h, char *line, int line_count,
 
         dprintf(NULL, "http_code=%d\n", s->http_code);
 
-        /* error codes are 4xx and 5xx */
+        /* error codes are 4xx and 5xx, but regard 401 as a success, so we
-        if (s->http_code >= 400 && s->http_code < 600)
+         * don't abort until all headers have been parsed. */
+        if (s->http_code >= 400 && s->http_code < 600 && s->http_code != 401)
             return -1;
     } else {
         while (*p != '\0' && *p != ':')
@@ -225,6 +237,10 @@ static int process_line(URLContext *h, char *line, int line_count,
         } else if (!strcmp (tag, "Transfer-Encoding") && !strncasecmp(p, "chunked", 7)) {
             s->filesize = -1;
             s->chunksize = 0;
+        } else if (!strcmp (tag, "WWW-Authenticate")) {
+            ff_http_auth_handle_header(&s->auth_state, tag, p);
+        } else if (!strcmp (tag, "Authentication-Info")) {
+            ff_http_auth_handle_header(&s->auth_state, tag, p);
         }
     }
     return 1;
@@ -236,22 +252,21 @@ static int http_connect(URLContext *h, const char *path, const char *hoststr,
     HTTPContext *s = h->priv_data;
     int post, err;
     char line[1024];
-    char *auth_b64;
+    char *authstr = NULL;
-    int auth_b64_len = (strlen(auth) + 2) / 3 * 4 + 1;
     int64_t off = s->off;
 
 
     /* send http header */
     post = h->flags & URL_WRONLY;
-    auth_b64 = av_malloc(auth_b64_len);
+    authstr = ff_http_auth_create_response(&s->auth_state, auth, path,
-    av_base64_encode(auth_b64, auth_b64_len, auth, strlen(auth));
+                                        post ? "POST" : "GET");
     snprintf(s->buffer, sizeof(s->buffer),
              "%s %s HTTP/1.1\r\n"
              "User-Agent: %s\r\n"
              "Accept: */*\r\n"
              "Range: bytes=%"PRId64"-\r\n"
              "Host: %s\r\n"
-             "Authorization: Basic %s\r\n"
+             "%s"
              "Connection: close\r\n"
              "%s"
              "\r\n",
@@ -260,10 +275,10 @@ static int http_connect(URLContext *h, const char *path, const char *hoststr,
              LIBAVFORMAT_IDENT,
              s->off,
              hoststr,
-             auth_b64,
+             authstr ? authstr : "",
              post ? "Transfer-Encoding: chunked\r\n" : "");
 
-    av_freep(&auth_b64);
+    av_freep(&authstr);
     if (http_write(h, s->buffer, strlen(s->buffer)) < 0)
         return AVERROR(EIO);
 

libavformat/httpauth.c

@@ -0,0 +1,132 @@
+/*
+ * HTTP authentication
+ * Copyright (c) 2010 Martin Storsjo
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "httpauth.h"
+#include "libavutil/base64.h"
+#include "libavutil/avstring.h"
+#include "avformat.h"
+#include <ctype.h>
+
+static void parse_key_value(const char *params,
+                            void (*callback_get_buf)(HTTPAuthState *state,
+                            const char *key, int key_len,
+                            char **dest, int *dest_len), HTTPAuthState *state)
+{
+    const char *ptr = params;
+
+    /* Parse key=value pairs. */
+    for (;;) {
+        const char *key;
+        char *dest = NULL, *dest_end;
+        int key_len, dest_len = 0;
+
+        /* Skip whitespace and potential commas. */
+        while (*ptr && (isspace(*ptr) || *ptr == ','))
+            ptr++;
+        if (!*ptr)
+            break;
+
+        key = ptr;
+
+        if (!(ptr = strchr(key, '=')))
+            break;
+        ptr++;
+        key_len = ptr - key;
+
+        callback_get_buf(state, key, key_len, &dest, &dest_len);
+        dest_end = dest + dest_len - 1;
+
+        if (*ptr == '\"') {
+            ptr++;
+            while (*ptr && *ptr != '\"') {
+                if (*ptr == '\\') {
+                    if (!ptr[1])
+                        break;
+                    if (dest && dest < dest_end)
+                        *dest++ = ptr[1];
+                    ptr += 2;
+                } else {
+                    if (dest && dest < dest_end)
+                        *dest++ = *ptr;
+                    ptr++;
+                }
+            }
+            if (*ptr == '\"')
+                ptr++;
+        } else {
+            for (; *ptr && !(isspace(*ptr) || *ptr == ','); ptr++)
+                if (dest && dest < dest_end)
+                    *dest++ = *ptr;
+        }
+        if (dest)
+            *dest = 0;
+    }
+}
+
+static void handle_basic_params(HTTPAuthState *state, const char *key,
+                                int key_len, char **dest, int *dest_len)
+{
+    if (!strncmp(key, "realm=", key_len)) {
+        *dest     =        state->realm;
+        *dest_len = sizeof(state->realm);
+    }
+}
+
+void ff_http_auth_handle_header(HTTPAuthState *state, const char *key,
+                                const char *value)
+{
+    if (!state)
+        return;
+
+    if (!strcmp(key, "WWW-Authenticate")) {
+        const char *p;
+        if (av_stristart(value, "Basic ", &p) &&
+            state->auth_type <= HTTP_AUTH_BASIC) {
+            state->auth_type = HTTP_AUTH_BASIC;
+            state->realm[0] = 0;
+            parse_key_value(p, handle_basic_params, state);
+        }
+    }
+}
+
+char *ff_http_auth_create_response(HTTPAuthState *state, const char *auth,
+                                   const char *path, const char *method)
+{
+    char *authstr = NULL;
+
+    if (!auth || !strchr(auth, ':'))
+        return NULL;
+
+    if (state->auth_type == HTTP_AUTH_BASIC) {
+        int auth_b64_len = (strlen(auth) + 2) / 3 * 4 + 1;
+        int len = auth_b64_len + 30;
+        char *ptr;
+        authstr = av_malloc(len);
+        if (!authstr)
+            return NULL;
+        snprintf(authstr, len, "Authorization: Basic ");
+        ptr = authstr + strlen(authstr);
+        av_base64_encode(ptr, auth_b64_len, auth, strlen(auth));
+        av_strlcat(ptr, "\r\n", len);
+    }
+    return authstr;
+}
+

libavformat/httpauth.h

@@ -0,0 +1,54 @@
+/*
+ * HTTP authentication
+ * Copyright (c) 2010 Martin Storsjo
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVFORMAT_HTTPAUTH_H
+#define AVFORMAT_HTTPAUTH_H
+
+/**
+ * Authentication types, ordered from weakest to strongest.
+ */
+typedef enum HTTPAuthType {
+    HTTP_AUTH_NONE = 0,    /**< No authentication specified */
+    HTTP_AUTH_BASIC,       /**< HTTP 1.0 Basic auth from RFC 1945
+                             *  (also in RFC 2617) */
+} HTTPAuthType;
+
+/**
+ * HTTP Authentication state structure. Must be zero-initialized
+ * before used with the functions below.
+ */
+typedef struct {
+    /**
+     * The currently chosen auth type.
+     */
+    HTTPAuthType auth_type;
+    /**
+     * Authentication realm
+     */
+    char realm[200];
+} HTTPAuthState;
+
+void ff_http_auth_handle_header(HTTPAuthState *state, const char *key,
+                                const char *value);
+char *ff_http_auth_create_response(HTTPAuthState *state, const char *auth,
+                                   const char *path, const char *method);
+
+#endif /* AVFORMAT_HTTPAUTH_H */