Adding upstream version 1:2.3.21+dfsg1.upstream/1%2.3.21+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 522 insertions, 0 deletions

diff --git a/src/lib-mail/rfc822-parser.c b/src/lib-mail/rfc822-parser.c
new file mode 100644
index 0000000..c8595b4
--- /dev/null
+++ b/src/lib-mail/rfc822-parser.c
@@ -0,0 +1,522 @@
+/* Copyright (c) 2005-2018 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "str.h"
+#include "strescape.h"
+#include "rfc822-parser.h"
+
+/*
+   atext        =       ALPHA / DIGIT / ; Any character except controls,
+                        "!" / "#" /     ;  SP, and specials.
+                        "$" / "%" /     ;  Used for atoms
+                        "&" / "'" /
+                        "*" / "+" /
+                        "-" / "/" /
+                        "=" / "?" /
+                        "^" / "_" /
+                        "`" / "{" /
+                        "|" / "}" /
+                        "~"
+
+  MIME:
+
+  token := 1*<any (US-ASCII) CHAR except SPACE, CTLs,
+              or tspecials>
+  tspecials :=  "(" / ")" / "<" / ">" / "@" /
+                "," / ";" / ":" / "\" / <">
+                "/" / "[" / "]" / "?" / "="
+
+  So token is same as dot-atom, except stops also at '/', '?' and '='.
+*/
+
+/* atext chars are marked with 1, alpha and digits with 2,
+   atext-but-mime-tspecials with 4 */
+unsigned char rfc822_atext_chars[256] = {
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0-15 */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 16-31 */
+	0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 4, /* 32-47 */
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 4, 0, 4, /* 48-63 */
+	0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, /* 64-79 */
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 1, 1, /* 80-95 */
+	1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, /* 96-111 */
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 0, /* 112-127 */
+
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
+};
+
+void rfc822_parser_init(struct rfc822_parser_context *ctx,
+			const unsigned char *data, size_t size,
+			string_t *last_comment)
+{
+	i_zero(ctx);
+	ctx->data = data;
+	ctx->end = data + size;
+	ctx->last_comment = last_comment;
+}
+
+int rfc822_skip_comment(struct rfc822_parser_context *ctx)
+{
+	const unsigned char *start;
+	size_t len;
+	int level = 1;
+
+	i_assert(*ctx->data == '(');
+
+	if (ctx->last_comment != NULL)
+		str_truncate(ctx->last_comment, 0);
+
+	start = ++ctx->data;
+	for (; ctx->data < ctx->end; ctx->data++) {
+		switch (*ctx->data) {
+		case '\0':
+			if (ctx->last_comment != NULL &&
+			    ctx->nul_replacement_str != NULL) {
+				str_append_data(ctx->last_comment, start,
+						ctx->data - start);
+				str_append(ctx->last_comment,
+					   ctx->nul_replacement_str);
+				start = ctx->data + 1;
+			}
+			break;
+		case '(':
+			level++;
+			break;
+		case ')':
+			if (--level == 0) {
+				if (ctx->last_comment != NULL) {
+					str_append_data(ctx->last_comment, start,
+							ctx->data - start);
+				}
+				ctx->data++;
+				return ctx->data < ctx->end ? 1 : 0;
+			}
+			break;
+		case '\n':
+			/* folding whitespace, remove the (CR)LF */
+			if (ctx->last_comment == NULL)
+				break;
+			len = ctx->data - start;
+			if (len > 0 && start[len-1] == '\r')
+				len--;
+			str_append_data(ctx->last_comment, start, len);
+			start = ctx->data + 1;
+			break;
+		case '\\':
+			ctx->data++;
+			if (ctx->data >= ctx->end)
+				return -1;
+
+			if (*ctx->data == '\r' || *ctx->data == '\n' ||
+			    *ctx->data == '\0') {
+				/* quoted-pair doesn't allow CR/LF/NUL.
+				   They are part of the obs-qp though, so don't
+				   return them as error. */
+				ctx->data--;
+				break;
+			}
+			if (ctx->last_comment != NULL) {
+				str_append_data(ctx->last_comment, start,
+						ctx->data - start - 1);
+			}
+			start = ctx->data;
+			break;
+		}
+	}
+
+	/* missing ')' */
+	return -1;
+}
+
+int rfc822_skip_lwsp(struct rfc822_parser_context *ctx)
+{
+	for (; ctx->data < ctx->end;) {
+		if (*ctx->data == ' ' || *ctx->data == '\t' ||
+		    *ctx->data == '\r' || *ctx->data == '\n') {
+                        ctx->data++;
+			continue;
+		}
+
+		if (*ctx->data != '(')
+			break;
+
+		if (rfc822_skip_comment(ctx) < 0)
+			return -1;
+	}
+	return ctx->data < ctx->end ? 1 : 0;
+}
+
+int rfc822_parse_atom(struct rfc822_parser_context *ctx, string_t *str)
+{
+	const unsigned char *start;
+
+	/*
+	   atom            = [CFWS] 1*atext [CFWS]
+	   atext           =
+	     ; Any character except controls, SP, and specials.
+	*/
+	if (ctx->data >= ctx->end || !IS_ATEXT(*ctx->data))
+		return -1;
+
+	for (start = ctx->data++; ctx->data < ctx->end; ctx->data++) {
+		if (IS_ATEXT(*ctx->data))
+			continue;
+
+		str_append_data(str, start, ctx->data - start);
+		return rfc822_skip_lwsp(ctx);
+	}
+
+	str_append_data(str, start, ctx->data - start);
+	return 0;
+}
+
+int rfc822_parse_dot_atom(struct rfc822_parser_context *ctx, string_t *str)
+{
+	const unsigned char *start;
+	int ret;
+
+	/*
+	   dot-atom        = [CFWS] dot-atom-text [CFWS]
+	   dot-atom-text   = 1*atext *("." 1*atext)
+
+	   atext           =
+	     ; Any character except controls, SP, and specials.
+
+	   For RFC-822 compatibility allow LWSP around '.'
+	*/
+	if (ctx->data >= ctx->end || !IS_ATEXT(*ctx->data))
+		return -1;
+
+	for (start = ctx->data++; ctx->data < ctx->end; ) {
+		if (IS_ATEXT(*ctx->data)) {
+			ctx->data++;
+			continue;
+		}
+
+		if (start == ctx->data)
+			return -1;
+		str_append_data(str, start, ctx->data - start);
+
+		if ((ret = rfc822_skip_lwsp(ctx)) <= 0)
+			return ret;
+
+		if (*ctx->data != '.')
+			return 1;
+
+		ctx->data++;
+		str_append_c(str, '.');
+
+		if (rfc822_skip_lwsp(ctx) <= 0)
+			return -1;
+		start = ctx->data;
+	}
+
+	i_assert(start != ctx->data);
+	str_append_data(str, start, ctx->data - start);
+	return 0;
+}
+
+int rfc822_parse_mime_token(struct rfc822_parser_context *ctx, string_t *str)
+{
+	const unsigned char *start;
+
+	for (start = ctx->data; ctx->data < ctx->end; ctx->data++) {
+		if (IS_ATEXT_NON_TSPECIAL(*ctx->data) || *ctx->data == '.')
+			continue;
+
+		str_append_data(str, start, ctx->data - start);
+		return rfc822_skip_lwsp(ctx);
+	}
+
+	str_append_data(str, start, ctx->data - start);
+	return 0;
+}
+
+int rfc822_parse_quoted_string(struct rfc822_parser_context *ctx, string_t *str)
+{
+	const unsigned char *start;
+	size_t len;
+
+	i_assert(ctx->data < ctx->end);
+	i_assert(*ctx->data == '"');
+	ctx->data++;
+
+	for (start = ctx->data; ctx->data < ctx->end; ctx->data++) {
+		switch (*ctx->data) {
+		case '\0':
+			if (ctx->nul_replacement_str != NULL) {
+				str_append_data(str, start, ctx->data - start);
+				str_append(str, ctx->nul_replacement_str);
+				start = ctx->data + 1;
+			}
+			break;
+		case '"':
+			str_append_data(str, start, ctx->data - start);
+			ctx->data++;
+			return rfc822_skip_lwsp(ctx);
+		case '\n':
+			/* folding whitespace, remove the (CR)LF */
+			len = ctx->data - start;
+			if (len > 0 && start[len-1] == '\r')
+				len--;
+			str_append_data(str, start, len);
+			start = ctx->data + 1;
+			break;
+		case '\\':
+			ctx->data++;
+			if (ctx->data >= ctx->end)
+				return -1;
+
+			if (*ctx->data == '\r' || *ctx->data == '\n' ||
+			    *ctx->data == '\0') {
+				/* quoted-pair doesn't allow CR/LF/NUL.
+				   They are part of the obs-qp though, so don't
+				   return them as error. */
+				ctx->data--;
+				break;
+			}
+			str_append_data(str, start, ctx->data - start - 1);
+			start = ctx->data;
+			break;
+		}
+	}
+
+	/* missing '"' */
+	return -1;
+}
+
+static int
+rfc822_parse_atom_or_dot(struct rfc822_parser_context *ctx, string_t *str)
+{
+	const unsigned char *start;
+
+	/*
+	   atom            = [CFWS] 1*atext [CFWS]
+	   atext           =
+	     ; Any character except controls, SP, and specials.
+
+	   The difference between this function and rfc822_parse_dot_atom()
+	   is that this doesn't just silently skip over all the whitespace.
+	*/
+	for (start = ctx->data; ctx->data < ctx->end; ctx->data++) {
+		if (IS_ATEXT(*ctx->data) || *ctx->data == '.')
+			continue;
+
+		str_append_data(str, start, ctx->data - start);
+		return rfc822_skip_lwsp(ctx);
+	}
+
+	str_append_data(str, start, ctx->data - start);
+	return 0;
+}
+
+int rfc822_parse_phrase(struct rfc822_parser_context *ctx, string_t *str)
+{
+	int ret;
+
+	/*
+	   phrase     = 1*word / obs-phrase
+	   word       = atom / quoted-string
+	   obs-phrase = word *(word / "." / CFWS)
+	*/
+
+	if (ctx->data >= ctx->end)
+		return 0;
+	if (*ctx->data == '.')
+		return -1;
+
+	for (;;) {
+		if (*ctx->data == '"')
+			ret = rfc822_parse_quoted_string(ctx, str);
+		else
+			ret = rfc822_parse_atom_or_dot(ctx, str);
+
+		if (ret <= 0)
+			return ret;
+
+		if (!IS_ATEXT(*ctx->data) && *ctx->data != '"'
+		    && *ctx->data != '.')
+			break;
+		str_append_c(str, ' ');
+	}
+	return rfc822_skip_lwsp(ctx);
+}
+
+static int
+rfc822_parse_domain_literal(struct rfc822_parser_context *ctx, string_t *str)
+{
+	const unsigned char *start;
+	size_t len;
+
+	/*
+	   domain-literal  = [CFWS] "[" *([FWS] dcontent) [FWS] "]" [CFWS]
+	   dcontent        = dtext / quoted-pair
+	   dtext           = NO-WS-CTL /     ; Non white space controls
+			     %d33-90 /       ; The rest of the US-ASCII
+			     %d94-126        ;  characters not including "[",
+					     ;  "]", or "\"
+	*/
+	i_assert(ctx->data < ctx->end);
+	i_assert(*ctx->data == '[');
+
+	for (start = ctx->data++; ctx->data < ctx->end; ctx->data++) {
+		switch (*ctx->data) {
+		case '\0':
+			if (ctx->nul_replacement_str != NULL) {
+				str_append_data(str, start, ctx->data - start);
+				str_append(str, ctx->nul_replacement_str);
+				start = ctx->data + 1;
+			}
+			break;
+		case '[':
+			/* not allowed */
+			return -1;
+		case ']':
+			str_append_data(str, start, ctx->data - start + 1);
+			ctx->data++;
+			return rfc822_skip_lwsp(ctx);
+		case '\n':
+			/* folding whitespace, remove the (CR)LF */
+			len = ctx->data - start;
+			if (len > 0 && start[len-1] == '\r')
+				len--;
+			str_append_data(str, start, len);
+			start = ctx->data + 1;
+			break;
+		case '\\':
+			/* note: the '\' is preserved in the output */
+			ctx->data++;
+			if (ctx->data >= ctx->end)
+				return -1;
+
+			if (*ctx->data == '\r' || *ctx->data == '\n' ||
+			    *ctx->data == '\0') {
+				/* quoted-pair doesn't allow CR/LF/NUL.
+				   They are part of the obs-qp though, so don't
+				   return them as error. */
+				str_append_data(str, start, ctx->data - start);
+				start = ctx->data;
+				ctx->data--;
+				break;
+			}
+		}
+	}
+
+	/* missing ']' */
+	return -1;
+}
+
+int rfc822_parse_domain(struct rfc822_parser_context *ctx, string_t *str)
+{
+	/*
+	   domain          = dot-atom / domain-literal / obs-domain
+	   domain-literal  = [CFWS] "[" *([FWS] dcontent) [FWS] "]" [CFWS]
+	   obs-domain      = atom *("." atom)
+	*/
+	i_assert(ctx->data < ctx->end);
+	i_assert(*ctx->data == '@');
+	ctx->data++;
+
+	if (rfc822_skip_lwsp(ctx) <= 0)
+		return -1;
+
+	if (*ctx->data == '[')
+		return rfc822_parse_domain_literal(ctx, str);
+	else
+		return rfc822_parse_dot_atom(ctx, str);
+}
+
+int rfc822_parse_content_type(struct rfc822_parser_context *ctx, string_t *str)
+{
+	size_t str_pos_0 = str->used;
+	if (rfc822_skip_lwsp(ctx) <= 0)
+		return -1;
+
+	/* get main type, require at least one byte */
+	if (rfc822_parse_mime_token(ctx, str) <= 0 ||
+	    str->used == str_pos_0)
+		return -1;
+
+	/* skip over "/" */
+	if (*ctx->data != '/') {
+		str_truncate(str, str_pos_0);
+		return -1;
+	}
+	ctx->data++;
+	if (rfc822_skip_lwsp(ctx) <= 0) {
+		str_truncate(str, str_pos_0);
+		return -1;
+	}
+	str_append_c(str, '/');
+
+	size_t str_pos = str->used;
+	/* get subtype, require at least one byte,
+	   and check the next separator to avoid accepting
+	   invalid values. */
+	int ret;
+	if ((ret = rfc822_parse_mime_token(ctx, str)) < 0 ||
+	    str->used == str_pos ||
+	    (ctx->data != ctx->end && *ctx->data != ';')) {
+		str_truncate(str, str_pos_0);
+		return -1;
+	}
+	return ret;
+}
+
+int rfc822_parse_content_param(struct rfc822_parser_context *ctx,
+			       const char **key_r, string_t *value)
+{
+	string_t *key;
+	int ret;
+
+	/* .. := *(";" parameter)
+	   parameter := attribute "=" value
+	   attribute := token
+	   value := token / quoted-string
+	*/
+	*key_r = NULL;
+	str_truncate(value, 0);
+
+	if (ctx->data >= ctx->end)
+		return 0;
+	if (*ctx->data != ';')
+		return -1;
+	ctx->data++;
+
+	if (rfc822_skip_lwsp(ctx) <= 0)
+		return -1;
+
+	key = t_str_new(64);
+	if (rfc822_parse_mime_token(ctx, key) <= 0)
+		return -1;
+
+	if (*ctx->data != '=')
+		return -1;
+	ctx->data++;
+
+	if ((ret = rfc822_skip_lwsp(ctx)) <= 0) {
+		/* broken / no value */
+	} else if (*ctx->data == '"') {
+		ret = rfc822_parse_quoted_string(ctx, value);
+	} else if (ctx->data < ctx->end && *ctx->data == '=') {
+		/* workaround for broken input:
+		   name==?utf-8?b?...?= */
+		while (ctx->data < ctx->end && *ctx->data != ';' &&
+		       *ctx->data != ' ' && *ctx->data != '\t' &&
+		       *ctx->data != '\r' && *ctx->data != '\n') {
+			str_append_c(value, *ctx->data);
+			ctx->data++;
+		}
+	} else {
+		ret = rfc822_parse_mime_token(ctx, value);
+	}
+
+	*key_r = str_c(key);
+	return ret < 0 ? -1 : 1;
+}