ARI - channel recording support

This patch is the first step in adding recording support to the
Asterisk REST Interface.

Recordings are stored in /var/spool/recording. Since recordings may be
destructive (overwriting existing files), the API rejects attempts to
escape the recording directory (avoiding issues if someone attempts to
record to ../../lib/sounds/greeting, for example).

(closes issue ASTERISK-21594)
(closes issue ASTERISK-21581)
Review: https://reviewboard.asterisk.org/r/2612/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@393550 65c4cc65-6c06-0410-ace0-fbb531ad65f3

5 files changed, 131 insertions, 6 deletions

diff --git a/main/app.c b/main/app.c
index a7a9029c9..031f6f28f 100644
--- a/main/app.c
+++ b/main/app.c
@@ -1169,7 +1169,7 @@ static int global_maxsilence = 0;
  * \retval 't' Recording ended from the message exceeding the maximum duration, or via DTMF in prepend mode
  * \retval dtmfchar Recording ended via the return value's DTMF character for either cancel or accept.
  */
-static int __ast_play_and_record(struct ast_channel *chan, const char *playfile, const char *recordfile, int maxtime, const char *fmt, int *duration, int *sound_duration, int beep, int silencethreshold, int maxsilence, const char *path, int prepend, const char *acceptdtmf, const char *canceldtmf, int skip_confirmation_sound)
+static int __ast_play_and_record(struct ast_channel *chan, const char *playfile, const char *recordfile, int maxtime, const char *fmt, int *duration, int *sound_duration, int beep, int silencethreshold, int maxsilence, const char *path, int prepend, const char *acceptdtmf, const char *canceldtmf, int skip_confirmation_sound, enum ast_record_if_exists if_exists)
 {
 	int d = 0;
 	char *fmts;
@@ -1186,6 +1186,21 @@ static int __ast_play_and_record(struct ast_channel *chan, const char *playfile,
 	struct ast_format rfmt;
 	struct ast_silence_generator *silgen = NULL;
 	char prependfile[PATH_MAX];
+	int ioflags;	/* IO flags for writing output file */
+
+	ioflags = O_CREAT|O_WRONLY;
+
+	switch (if_exists) {
+	case AST_RECORD_IF_EXISTS_FAIL:
+		ioflags |= O_EXCL;
+		break;
+	case AST_RECORD_IF_EXISTS_OVERWRITE:
+		ioflags |= O_TRUNC;
+		break;
+	case AST_RECORD_IF_EXISTS_APPEND:
+		ioflags |= O_APPEND;
+		break;
+	}
 
 	ast_format_clear(&rfmt);
 	if (silencethreshold < 0) {
@@ -1239,7 +1254,7 @@ static int __ast_play_and_record(struct ast_channel *chan, const char *playfile,
 
 	end = start = time(NULL);  /* pre-initialize end to be same as start in case we never get into loop */
 	for (x = 0; x < fmtcnt; x++) {
-		others[x] = ast_writefile(prepend ? prependfile : recordfile, sfmt[x], comment, O_TRUNC, 0, AST_FILE_MODE);
+		others[x] = ast_writefile(prepend ? prependfile : recordfile, sfmt[x], comment, ioflags, 0, AST_FILE_MODE);
 		ast_verb(3, "x=%d, open writing:  %s format: %s, %p\n", x, prepend ? prependfile : recordfile, sfmt[x], others[x]);
 
 		if (!others[x]) {
@@ -1477,19 +1492,19 @@ static int __ast_play_and_record(struct ast_channel *chan, const char *playfile,
 static const char default_acceptdtmf[] = "#";
 static const char default_canceldtmf[] = "";
 
-int ast_play_and_record_full(struct ast_channel *chan, const char *playfile, const char *recordfile, int maxtime, const char *fmt, int *duration, int *sound_duration, int silencethreshold, int maxsilence, const char *path, const char *acceptdtmf, const char *canceldtmf)
+int ast_play_and_record_full(struct ast_channel *chan, const char *playfile, const char *recordfile, int maxtime, const char *fmt, int *duration, int *sound_duration, int silencethreshold, int maxsilence, const char *path, const char *acceptdtmf, const char *canceldtmf, int skip_confirmation_sound, enum ast_record_if_exists if_exists)
 {
-	return __ast_play_and_record(chan, playfile, recordfile, maxtime, fmt, duration, sound_duration, 0, silencethreshold, maxsilence, path, 0, S_OR(acceptdtmf, default_acceptdtmf), S_OR(canceldtmf, default_canceldtmf), 0);
+	return __ast_play_and_record(chan, playfile, recordfile, maxtime, fmt, duration, sound_duration, 0, silencethreshold, maxsilence, path, 0, S_OR(acceptdtmf, default_acceptdtmf), S_OR(canceldtmf, default_canceldtmf), skip_confirmation_sound, if_exists);
 }
 
 int ast_play_and_record(struct ast_channel *chan, const char *playfile, const char *recordfile, int maxtime, const char *fmt, int *duration, int *sound_duration, int silencethreshold, int maxsilence, const char *path)
 {
-	return __ast_play_and_record(chan, playfile, recordfile, maxtime, fmt, duration, sound_duration, 0, silencethreshold, maxsilence, path, 0, default_acceptdtmf, default_canceldtmf, 0);
+	return __ast_play_and_record(chan, playfile, recordfile, maxtime, fmt, duration, sound_duration, 0, silencethreshold, maxsilence, path, 0, default_acceptdtmf, default_canceldtmf, 0, AST_RECORD_IF_EXISTS_OVERWRITE);
 }
 
 int ast_play_and_prepend(struct ast_channel *chan, char *playfile, char *recordfile, int maxtime, char *fmt, int *duration, int *sound_duration, int beep, int silencethreshold, int maxsilence)
 {
-	return __ast_play_and_record(chan, playfile, recordfile, maxtime, fmt, duration, sound_duration, beep, silencethreshold, maxsilence, NULL, 1, default_acceptdtmf, default_canceldtmf, 1);
+	return __ast_play_and_record(chan, playfile, recordfile, maxtime, fmt, duration, sound_duration, beep, silencethreshold, maxsilence, NULL, 1, default_acceptdtmf, default_canceldtmf, 1, AST_RECORD_IF_EXISTS_OVERWRITE);
 }
 
 /* Channel group core functions */
diff --git a/main/asterisk.c b/main/asterisk.c
index c1ce2c0f1..aa33f31e4 100644
--- a/main/asterisk.c
+++ b/main/asterisk.c
@@ -373,6 +373,7 @@ struct _cfg_paths {
 	char module_dir[PATH_MAX];
 	char spool_dir[PATH_MAX];
 	char monitor_dir[PATH_MAX];
+	char recording_dir[PATH_MAX];
 	char var_dir[PATH_MAX];
 	char data_dir[PATH_MAX];
 	char log_dir[PATH_MAX];
@@ -397,6 +398,7 @@ const char *ast_config_AST_CONFIG_FILE	= cfg_paths.config_file;
 const char *ast_config_AST_MODULE_DIR	= cfg_paths.module_dir;
 const char *ast_config_AST_SPOOL_DIR	= cfg_paths.spool_dir;
 const char *ast_config_AST_MONITOR_DIR	= cfg_paths.monitor_dir;
+const char *ast_config_AST_RECORDING_DIR	= cfg_paths.recording_dir;
 const char *ast_config_AST_VAR_DIR	= cfg_paths.var_dir;
 const char *ast_config_AST_DATA_DIR	= cfg_paths.data_dir;
 const char *ast_config_AST_LOG_DIR	= cfg_paths.log_dir;
@@ -3306,6 +3308,7 @@ static void ast_readconfig(void)
 	ast_copy_string(cfg_paths.spool_dir, DEFAULT_SPOOL_DIR, sizeof(cfg_paths.spool_dir));
 	ast_copy_string(cfg_paths.module_dir, DEFAULT_MODULE_DIR, sizeof(cfg_paths.module_dir));
 	snprintf(cfg_paths.monitor_dir, sizeof(cfg_paths.monitor_dir), "%s/monitor", cfg_paths.spool_dir);
+	snprintf(cfg_paths.recording_dir, sizeof(cfg_paths.recording_dir), "%s/recording", cfg_paths.spool_dir);
 	ast_copy_string(cfg_paths.var_dir, DEFAULT_VAR_DIR, sizeof(cfg_paths.var_dir));
 	ast_copy_string(cfg_paths.data_dir, DEFAULT_DATA_DIR, sizeof(cfg_paths.data_dir));
 	ast_copy_string(cfg_paths.log_dir, DEFAULT_LOG_DIR, sizeof(cfg_paths.log_dir));
@@ -3341,6 +3344,7 @@ static void ast_readconfig(void)
 		} else if (!strcasecmp(v->name, "astspooldir")) {
 			ast_copy_string(cfg_paths.spool_dir, v->value, sizeof(cfg_paths.spool_dir));
 			snprintf(cfg_paths.monitor_dir, sizeof(cfg_paths.monitor_dir), "%s/monitor", v->value);
+			snprintf(cfg_paths.recording_dir, sizeof(cfg_paths.recording_dir), "%s/recording", v->value);
 		} else if (!strcasecmp(v->name, "astvarlibdir")) {
 			ast_copy_string(cfg_paths.var_dir, v->value, sizeof(cfg_paths.var_dir));
 			if (!found.dbdir)
diff --git a/main/channel.c b/main/channel.c
index 9d1ec69c2..3bc5c0a75 100644
--- a/main/channel.c
+++ b/main/channel.c
@@ -3029,6 +3029,15 @@ int ast_answer(struct ast_channel *chan)
 	return __ast_answer(chan, 0);
 }
 
+inline int ast_auto_answer(struct ast_channel *chan)
+{
+	if (ast_channel_state(chan) == AST_STATE_UP) {
+		/* Already answered */
+		return 0;
+	}
+	return ast_answer(chan);
+}
+
 int ast_channel_get_duration(struct ast_channel *chan)
 {
 	ast_assert(NULL != chan);
diff --git a/main/file.c b/main/file.c
index 016afd197..cb495b310 100644
--- a/main/file.c
+++ b/main/file.c
@@ -1020,6 +1020,9 @@ int ast_closestream(struct ast_filestream *f)
 	 * We close the stream in order to quit queuing frames now, because we might
 	 * change the writeformat, which could result in a subsequent write error, if
 	 * the format is different. */
+	if (f == NULL) {
+		return 0;
+	}
 	filestream_close(f);
 	ao2_ref(f, -1);
 	return 0;
diff --git a/main/utils.c b/main/utils.c
index 208a4d326..04f612703 100644
--- a/main/utils.c
+++ b/main/utils.c
@@ -2105,6 +2105,100 @@ int ast_mkdir(const char *path, int mode)
 	return 0;
 }
 
+static int safe_mkdir(const char *base_path, char *path, int mode)
+{
+	RAII_VAR(char *, absolute_path, NULL, free);
+
+	absolute_path = realpath(path, NULL);
+
+	if (absolute_path) {
+		/* Path exists, but is it in the right place? */
+		if (!ast_begins_with(absolute_path, base_path)) {
+			return EPERM;
+		}
+
+		/* It is in the right place! */
+		return 0;
+	} else {
+		/* Path doesn't exist. */
+
+		/* The slash terminating the subpath we're checking */
+		char *path_term = strchr(path, '/');
+		/* True indicates the parent path is within base_path */
+		int parent_is_safe = 0;
+		int res;
+
+		while (path_term) {
+			RAII_VAR(char *, absolute_subpath, NULL, free);
+
+			/* Truncate the path one past the slash */
+			char c = *(path_term + 1);
+			*(path_term + 1) = '\0';
+			absolute_subpath = realpath(path, NULL);
+
+			if (absolute_subpath) {
+				/* Subpath exists, but is it safe? */
+				parent_is_safe = ast_begins_with(
+					absolute_subpath, base_path);
+			} else if (parent_is_safe) {
+				/* Subpath does not exist, but parent is safe
+				 * Create it */
+				res = mkdir(path, mode);
+				if (res != 0) {
+					ast_assert(errno != EEXIST);
+					return errno;
+				}
+			} else {
+				/* Subpath did not exist, parent was not safe
+				 * Fail! */
+				errno = EPERM;
+				return errno;
+			}
+			/* Restore the path */
+			*(path_term + 1) = c;
+			/* Move on to the next slash */
+			path_term = strchr(path_term + 1, '/');
+		}
+
+		/* Now to build the final path, but only if it's safe */
+		if (!parent_is_safe) {
+			errno = EPERM;
+			return errno;
+		}
+
+		res = mkdir(path, mode);
+		if (res != 0 && errno != EEXIST) {
+			return errno;
+		}
+
+		return 0;
+	}
+}
+
+int ast_safe_mkdir(const char *base_path, const char *path, int mode)
+{
+	RAII_VAR(char *, absolute_base_path, NULL, free);
+	RAII_VAR(char *, p, NULL, ast_free);
+
+	if (base_path == NULL || path == NULL) {
+		errno = EFAULT;
+		return errno;
+	}
+
+	p = ast_strdup(path);
+	if (p == NULL) {
+		errno = ENOMEM;
+		return errno;
+	}
+
+	absolute_base_path = realpath(base_path, NULL);
+	if (absolute_base_path == NULL) {
+		return errno;
+	}
+
+	return safe_mkdir(absolute_base_path, p, mode);
+}
+
 int ast_utils_init(void)
 {
 	dev_urandom_fd = open("/dev/urandom", O_RDONLY);