Merging OAuth branch. It should be stable now and is documented.

1 files changed, 439 insertions, 0 deletions

diff --git a/lib/oauth.c b/lib/oauth.c
new file mode 100644
index 00000000..9fb83922
--- /dev/null
+++ b/lib/oauth.c
@@ -0,0 +1,439 @@
+/***************************************************************************\
+*                                                                           *
+*  BitlBee - An IRC to IM gateway                                           *
+*  Simple OAuth client (consumer) implementation.                           *
+*                                                                           *
+*  Copyright 2010 Wilmer van der Gaast <wilmer@gaast.net>                   *
+*                                                                           *
+*  This library 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, version            *
+*  2.1.                                                                     *
+*                                                                           *
+*  This library 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 this library; if not, write to the Free Software Foundation,  *
+*  Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA           *
+*                                                                           *
+\***************************************************************************/
+
+#include <glib.h>
+#include <gmodule.h>
+#include <stdlib.h>
+#include <string.h>
+#include "http_client.h"
+#include "base64.h"
+#include "misc.h"
+#include "sha1.h"
+#include "url.h"
+#include "oauth.h"
+
+#define CONSUMER_KEY "xsDNKJuNZYkZyMcu914uEA"
+#define CONSUMER_SECRET "FCxqcr0pXKzsF9ajmP57S3VQ8V6Drk4o2QYtqMcOszo"
+/* How can it be a secret if it's right here in the source code? No clue... */
+
+#define HMAC_BLOCK_SIZE 64
+
+static char *oauth_sign( const char *method, const char *url,
+                         const char *params, const char *token_secret )
+{
+	sha1_state_t sha1;
+	uint8_t hash[sha1_hash_size];
+	uint8_t key[HMAC_BLOCK_SIZE+1];
+	char *s;
+	int i;
+	
+	/* Create K. If our current key is >64 chars we have to hash it,
+	   otherwise just pad. */
+	memset( key, 0, HMAC_BLOCK_SIZE );
+	i = strlen( CONSUMER_SECRET ) + 1 + ( token_secret ? strlen( token_secret ) : 0 );
+	if( i > HMAC_BLOCK_SIZE )
+	{
+		sha1_init( &sha1 );
+		sha1_append( &sha1, (uint8_t*) CONSUMER_SECRET, strlen( CONSUMER_SECRET ) );
+		sha1_append( &sha1, (uint8_t*) "&", 1 );
+		if( token_secret )
+			sha1_append( &sha1, (uint8_t*) token_secret, strlen( token_secret ) );
+		sha1_finish( &sha1, key );
+	}
+	else
+	{
+		g_snprintf( (gchar*) key, HMAC_BLOCK_SIZE + 1, "%s&%s",
+		            CONSUMER_SECRET, token_secret ? : "" );
+	}
+	
+	/* Inner part: H(K XOR 0x36, text) */
+	sha1_init( &sha1 );
+	
+	for( i = 0; i < HMAC_BLOCK_SIZE; i ++ )
+		key[i] ^= 0x36;
+	sha1_append( &sha1, key, HMAC_BLOCK_SIZE );
+	
+	/* OAuth: text = method&url&params, all http_encoded. */
+	sha1_append( &sha1, (const uint8_t*) method, strlen( method ) );
+	sha1_append( &sha1, (const uint8_t*) "&", 1 );
+	
+	s = g_new0( char, strlen( url ) * 3 + 1 );
+	strcpy( s, url );
+	http_encode( s );
+	sha1_append( &sha1, (const uint8_t*) s, strlen( s ) );
+	sha1_append( &sha1, (const uint8_t*) "&", 1 );
+	g_free( s );
+	
+	s = g_new0( char, strlen( params ) * 3 + 1 );
+	strcpy( s, params );
+	http_encode( s );
+	sha1_append( &sha1, (const uint8_t*) s, strlen( s ) );
+	g_free( s );
+	
+	sha1_finish( &sha1, hash );
+	
+	/* Final result: H(K XOR 0x5C, inner stuff) */
+	sha1_init( &sha1 );
+	for( i = 0; i < HMAC_BLOCK_SIZE; i ++ )
+		key[i] ^= 0x36 ^ 0x5c;
+	sha1_append( &sha1, key, HMAC_BLOCK_SIZE );
+	sha1_append( &sha1, hash, sha1_hash_size );
+	sha1_finish( &sha1, hash );
+	
+	/* base64_encode + HTTP escape it (both consumers 
+	   need it that away) and we're done. */
+	s = base64_encode( hash, sha1_hash_size );
+	s = g_realloc( s, strlen( s ) * 3 + 1 );
+	http_encode( s );
+	
+	return s;
+}
+
+static char *oauth_nonce()
+{
+	unsigned char bytes[9];
+	
+	random_bytes( bytes, sizeof( bytes ) );
+	return base64_encode( bytes, sizeof( bytes ) );
+}
+
+void oauth_params_add( GSList **params, const char *key, const char *value )
+{
+	char *item;
+	
+	item = g_strdup_printf( "%s=%s", key, value );
+	*params = g_slist_insert_sorted( *params, item, (GCompareFunc) strcmp );
+}
+
+void oauth_params_del( GSList **params, const char *key )
+{
+	int key_len = strlen( key );
+	GSList *l, *n;
+	
+	for( l = *params; l; l = n )
+	{
+		n = l->next;
+		
+		if( strncmp( (char*) l->data, key, key_len ) == 0 &&
+		    ((char*)l->data)[key_len] == '=' )
+		{
+			g_free( l->data );
+			*params = g_slist_remove( *params, l->data );
+		}
+	}
+}
+
+void oauth_params_set( GSList **params, const char *key, const char *value )
+{
+	oauth_params_del( params, key );
+	oauth_params_add( params, key, value );
+}
+
+const char *oauth_params_get( GSList **params, const char *key )
+{
+	int key_len = strlen( key );
+	GSList *l;
+	
+	for( l = *params; l; l = l->next )
+	{
+		if( strncmp( (char*) l->data, key, key_len ) == 0 &&
+		    ((char*)l->data)[key_len] == '=' )
+			return (const char*) l->data + key_len + 1;
+	}
+	
+	return NULL;
+}
+
+static void oauth_params_parse( GSList **params, char *in )
+{
+	char *amp, *eq, *s;
+	
+	while( in && *in )
+	{
+		eq = strchr( in, '=' );
+		if( !eq )
+			break;
+		
+		*eq = '\0';
+		if( ( amp = strchr( eq + 1, '&' ) ) )
+			*amp = '\0';
+		
+		s = g_strdup( eq + 1 );
+		http_decode( s );
+		oauth_params_add( params, in, s );
+		g_free( s );
+		
+		*eq = '=';
+		if( amp == NULL )
+			break;
+		
+		*amp = '&';
+		in = amp + 1;
+	}
+}
+
+void oauth_params_free( GSList **params )
+{
+	while( params && *params )
+	{
+		g_free( (*params)->data );
+		*params = g_slist_remove( *params, (*params)->data );
+	}
+}
+
+char *oauth_params_string( GSList *params )
+{
+	GSList *l;
+	GString *str = g_string_new( "" );
+	
+	for( l = params; l; l = l->next )
+	{
+		char *s, *eq;
+		
+		s = g_malloc( strlen( l->data ) * 3 + 1 );
+		strcpy( s, l->data );
+		if( ( eq = strchr( s, '=' ) ) )
+			http_encode( eq + 1 );
+		g_string_append( str, s );
+		g_free( s );
+		
+		if( l->next )
+			g_string_append_c( str, '&' );
+	}
+	
+	return g_string_free( str, FALSE );
+}
+
+void oauth_info_free( struct oauth_info *info )
+{
+	if( info )
+	{
+		g_free( info->auth_params );
+		g_free( info->request_token );
+		g_free( info->access_token );
+		g_free( info );
+	}
+}
+
+static void oauth_add_default_params( GSList **params )
+{
+	char *s;
+	
+	oauth_params_set( params, "oauth_consumer_key", CONSUMER_KEY );
+	oauth_params_set( params, "oauth_signature_method", "HMAC-SHA1" );
+	
+	s = g_strdup_printf( "%d", (int) time( NULL ) );
+	oauth_params_set( params, "oauth_timestamp", s );
+	g_free( s );
+	
+	s = oauth_nonce();
+	oauth_params_set( params, "oauth_nonce", s );
+	g_free( s );
+	
+	oauth_params_set( params, "oauth_version", "1.0" );
+}
+
+static void *oauth_post_request( const char *url, GSList **params_, http_input_function func, void *data )
+{
+	GSList *params = NULL;
+	char *s, *params_s, *post;
+	void *req;
+	url_t url_p;
+	
+	if( !url_set( &url_p, url ) )
+	{
+		oauth_params_free( params_ );
+		return NULL;
+	}
+	
+	if( params_ )
+		params = *params_;
+	
+	oauth_add_default_params( &params );
+	
+	params_s = oauth_params_string( params );
+	oauth_params_free( &params );
+	
+	s = oauth_sign( "POST", url, params_s, NULL );
+	post = g_strdup_printf( "%s&oauth_signature=%s", params_s, s );
+	g_free( params_s );
+	g_free( s );
+	
+	s = g_strdup_printf( "POST %s HTTP/1.0\r\n"
+	                     "Host: %s\r\n"
+	                     "Content-Type: application/x-www-form-urlencoded\r\n"
+	                     "Content-Length: %zd\r\n"
+	                     "\r\n"
+	                     "%s", url_p.file, url_p.host, strlen( post ), post );
+	g_free( post );
+	
+	req = http_dorequest( url_p.host, url_p.port, url_p.proto == PROTO_HTTPS,
+	                      s, func, data );
+	g_free( s );
+	
+	return req;
+}
+
+static void oauth_request_token_done( struct http_request *req );
+
+struct oauth_info *oauth_request_token( const char *url, oauth_cb func, void *data )
+{
+	struct oauth_info *st = g_new0( struct oauth_info, 1 );
+	GSList *params = NULL;
+	
+	st->func = func;
+	st->data = data;
+	
+	oauth_params_add( &params, "oauth_callback", "oob" );
+	
+	if( !oauth_post_request( url, &params, oauth_request_token_done, st ) )
+	{
+		oauth_info_free( st );
+		return NULL;
+	}
+	
+	return st;
+}
+
+static void oauth_request_token_done( struct http_request *req )
+{
+	struct oauth_info *st = req->data;
+	
+	st->http = req;
+	
+	if( req->status_code == 200 )
+	{
+		GSList *params = NULL;
+		
+		st->auth_params = g_strdup( req->reply_body );
+		oauth_params_parse( &params, st->auth_params );
+		st->request_token = g_strdup( oauth_params_get( &params, "oauth_token" ) );
+		oauth_params_free( &params );
+	}
+	
+	st->stage = OAUTH_REQUEST_TOKEN;
+	if( !st->func( st ) )
+		oauth_info_free( st );
+}
+
+static void oauth_access_token_done( struct http_request *req );
+
+void oauth_access_token( const char *url, const char *pin, struct oauth_info *st )
+{
+	GSList *params = NULL;
+	
+	oauth_params_add( &params, "oauth_token", st->request_token );
+	oauth_params_add( &params, "oauth_verifier", pin );
+	
+	if( !oauth_post_request( url, &params, oauth_access_token_done, st ) )
+		oauth_info_free( st );
+}
+
+static void oauth_access_token_done( struct http_request *req )
+{
+	struct oauth_info *st = req->data;
+	
+	st->http = req;
+	
+	if( req->status_code == 200 )
+	{
+		GSList *params = NULL;
+		const char *token, *token_secret;
+		
+		oauth_params_parse( &params, req->reply_body );
+		token = oauth_params_get( &params, "oauth_token" );
+		token_secret = oauth_params_get( &params, "oauth_token_secret" );
+		st->access_token = g_strdup_printf(
+			"oauth_token=%s&oauth_token_secret=%s", token, token_secret );
+		oauth_params_free( &params );
+	}
+	
+	st->stage = OAUTH_ACCESS_TOKEN;
+	st->func( st );
+	oauth_info_free( st );
+}
+
+char *oauth_http_header( char *access_token, const char *method, const char *url, char *args )
+{
+	GSList *params = NULL, *l;
+	char *token_secret, *sig, *params_s, *s;
+	GString *ret = NULL;
+	
+	/* First, get the two pieces of info from the access token that we need. */
+	oauth_params_parse( &params, access_token );
+	if( params == NULL )
+		goto err;
+	
+	/* Pick out the token secret, we shouldn't include it but use it for signing. */
+	token_secret = g_strdup( oauth_params_get( &params, "oauth_token_secret" ) );
+	if( token_secret == NULL )
+		goto err;
+	oauth_params_del( &params, "oauth_token_secret" );
+	
+	oauth_add_default_params( &params );
+	
+	/* Start building the OAuth header. 'key="value", '... */
+	ret = g_string_new( "OAuth " );
+	for( l = params; l; l = l->next )
+	{
+		char *kv = l->data;
+		char *eq = strchr( kv, '=' );
+		char esc[strlen(kv)*3+1];
+		
+		if( eq == NULL )
+			break; /* WTF */
+		
+		strcpy( esc, eq + 1 );
+		http_encode( esc );
+		
+		g_string_append_len( ret, kv, eq - kv + 1 );
+		g_string_append_c( ret, '"' );
+		g_string_append( ret, esc );
+		g_string_append( ret, "\", " );
+	}
+	
+	/* Now, before generating the signature, add GET/POST arguments to params
+	   since they should be included in the base signature string (but not in
+	   the HTTP header). */
+	if( args )
+		oauth_params_parse( &params, args );
+	if( ( s = strchr( url, '?' ) ) )
+	{
+		s = g_strdup( s + 1 );
+		oauth_params_parse( &params, s + 1 );
+		g_free( s );
+	}
+	
+	/* Append the signature and we're done! */
+	params_s = oauth_params_string( params );
+	sig = oauth_sign( method, url, params_s, token_secret );
+	g_string_append_printf( ret, "oauth_signature=\"%s\"", sig );
+	g_free( params_s );
+	
+err:
+	oauth_params_free( &params );
+	g_free( sig );
+	g_free( token_secret );
+	
+	return ret ? g_string_free( ret, FALSE ) : NULL;
+}