From b9a2f18466a0d3377bab3e7a57691bdd75d8507c Mon Sep 17 00:00:00 2001

From: Timo Sirainen <timo.sirainen@open-xchange.com>

Date: Mon, 17 Aug 2020 17:32:11 +0300

Subject: [PATCH] lib-imap: Add imap_parser_read_tag() and _read_command_name()

---

 src/lib-imap/imap-parser.c      | 67 +++++++++++++++++++++++++++++++++

 src/lib-imap/imap-parser.h      |  7 ++++

 src/lib-imap/test-imap-parser.c | 67 +++++++++++++++++++++++++++++++++

 3 files changed, 141 insertions(+)

diff --git a/src/lib-imap/imap-parser.c b/src/lib-imap/imap-parser.c

index b6c6e63fb1..52d79282fa 100644

--- a/src/lib-imap/imap-parser.c

+++ b/src/lib-imap/imap-parser.c

@@ -947,3 +947,70 @@ const char *imap_parser_read_word(struct imap_parser *parser)

 		return NULL;

 	}

 }

+

+static int

+imap_parser_read_next_atom(struct imap_parser *parser, bool parsing_tag,

+			   const char **atom_r)

+{

+	const unsigned char *data;

+	size_t i, data_size;

+

+	data = i_stream_get_data(parser->input, &data_size);

+

+	/*

+	   tag            = 1*<any ASTRING-CHAR except "+">

+	   ASTRING-CHAR   = ATOM-CHAR / resp-specials

+	   ATOM-CHAR      = <any CHAR except atom-specials>

+

+	   x-command      = "X" atom <experimental command arguments>

+	   atom           = 1*ATOM-CHAR

+	*/

+	for (i = 0; i < data_size; i++) {

+		/* explicitly check for atom-specials, because

+		   IS_ATOM_PARSER_INPUT() allows some atom-specials */

+		switch (data[i]) {

+		case ' ':

+		case '\r':

+		case '\n':

+			data_size = i + (data[i] == ' ' ? 1 : 0);

+			parser->line_size += data_size;

+			i_stream_skip(parser->input, data_size);

+			*atom_r = p_strndup(parser->pool, data, i);

+			/* don't allow empty string */

+			return i == 0 ? -1 : 1;

+		/* atom-specials: */

+		case '(':

+		case ')':

+		case '{':

+		/* list-wildcards: */

+		case '%':

+		case '*':

+		/* quoted-specials: */

+		case '"':

+		case '\\':

+		/* resp-specials: */

+		case ']':

+			return -1;

+		case '+':

+			if (parsing_tag)

+				return -1;

+			break;

+		default:

+			if ((unsigned char)data[i] < ' ' ||

+			    (unsigned char)data[i] >= 0x80)

+				return -1;

+		}

+	}

+	return 0;

+}

+

+int imap_parser_read_tag(struct imap_parser *parser, const char **tag_r)

+{

+	return imap_parser_read_next_atom(parser, TRUE, tag_r);

+}

+

+int imap_parser_read_command_name(struct imap_parser *parser,

+				  const char **name_r)

+{

+	return imap_parser_read_next_atom(parser, FALSE, name_r);

+}

diff --git a/src/lib-imap/imap-parser.h b/src/lib-imap/imap-parser.h

index e5d01c17f2..5e09d61d2b 100644

--- a/src/lib-imap/imap-parser.h

+++ b/src/lib-imap/imap-parser.h

@@ -101,5 +101,12 @@ int imap_parser_finish_line(struct imap_parser *parser, unsigned int count,

 /* Read one word - used for reading tag and command name.

    Returns NULL if more data is needed. */

 const char *imap_parser_read_word(struct imap_parser *parser);

+/* Read command tag. Returns 1 if tag was returned, 0 if more data is needed,

+   -1 if input isn't a valid tag. */

+int imap_parser_read_tag(struct imap_parser *parser, const char **tag_r);

+/* Read command name. Returns 1 if command name was returned, 0 if more data is

+   needed, -1 if input isn't a valid command name string. */

+int imap_parser_read_command_name(struct imap_parser *parser,

+				  const char **name_r);

 #endif

diff --git a/src/lib-imap/test-imap-parser.c b/src/lib-imap/test-imap-parser.c

index 93ef8fd59b..3ca4e34858 100644

--- a/src/lib-imap/test-imap-parser.c

+++ b/src/lib-imap/test-imap-parser.c

@@ -79,10 +79,77 @@ static void test_imap_parser_partial_list(void)

 	test_end();

 }

+static void test_imap_parser_read_tag_cmd(void)

+{

+	enum read_type {

+		BOTH,

+		TAG,

+		COMMAND

+	};

+	struct {

+		const char *input;

+		const char *tag;

+		int ret;

+		enum read_type type;

+	} tests[] = {

+		{ "tag foo", "tag", 1, BOTH },

+		{ "tag\r", "tag", 1, BOTH },

+		{ "tag\rfoo", "tag", 1, BOTH },

+		{ "tag\nfoo", "tag", 1, BOTH },

+		{ "tag\r\nfoo", "tag", 1, BOTH },

+		{ "\n", NULL, -1, BOTH },

+		{ "tag", NULL, 0, BOTH },

+		{ "tag\t", NULL, -1, BOTH },

+		{ "tag\001", NULL, -1, BOTH },

+		{ "tag\x80", NULL, -1, BOTH },

+		{ "tag(", NULL, -1, BOTH },

+		{ "tag)", NULL, -1, BOTH },

+		{ "tag{", NULL, -1, BOTH },

+		{ "tag/ ", "tag/", 1, BOTH },

+		{ "tag%", NULL, -1, BOTH },

+		{ "tag*", NULL, -1, BOTH },

+		{ "tag\"", NULL, -1, BOTH },

+		{ "tag\\", NULL, -1, BOTH },

+		{ "tag+", NULL, -1, TAG },

+		{ "tag+ ", "tag+", 1, COMMAND },

+	};

+	struct istream *input;

+	struct imap_parser *parser;

+	const char *atom;

+	int ret;

+

+	test_begin("imap_parser_read_tag and imap_parser_read_command_name");

+	for (unsigned int i = 0; i < N_ELEMENTS(tests); i++) {

+		if (tests[i].type != COMMAND) {

+			input = test_istream_create(tests[i].input);

+			test_assert(i_stream_read(input) > 0);

+			parser = imap_parser_create(input, NULL, 1024);

+			ret = imap_parser_read_tag(parser, &atom);

+			test_assert_idx(ret == tests[i].ret, i);

+			test_assert_idx(ret <= 0 || strcmp(tests[i].tag, atom) == 0, i);

+			imap_parser_unref(&parser);

+			i_stream_destroy(&input);

+		}

+

+		if (tests[i].type != TAG) {

+			input = test_istream_create(tests[i].input);

+			test_assert(i_stream_read(input) > 0);

+			parser = imap_parser_create(input, NULL, 1024);

+			ret = imap_parser_read_command_name(parser, &atom);

+			test_assert_idx(ret == tests[i].ret, i);

+			test_assert_idx(ret <= 0 || strcmp(tests[i].tag, atom) == 0, i);

+			imap_parser_unref(&parser);

+			i_stream_destroy(&input);

+		}

+	}

+	test_end();

+}

+

 int main(void)

 {

 	static void (*const test_functions[])(void) = {

 		test_imap_parser_crlf,

+		test_imap_parser_read_tag_cmd,

 		NULL

 	};

 	return test_run(test_functions);