[commit] master: make IMAP parsing case insensitive

[Oswald B. <os...@us...>]

commit 6b9d4311d284debb0dba1d32757c965150d0d1d1
Author: Oswald Buddenhagen <os...@us...>
Date:   Thu Nov 25 13:40:09 2021 +0100

    make IMAP parsing case insensitive
    
    it's easy to overlook, but the spec demands this. we got away with it so
    far, as everyone just uses UPPERCASE ... for the things we use so far.

 src/common.h   |  2 ++
 src/drv_imap.c | 19 +++++++++++++------
 src/util.c     |  7 +++++++
 3 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/src/common.h b/src/common.h
index 4b431365..9a25b56b 100644
--- a/src/common.h
+++ b/src/common.h
@@ -189,6 +189,8 @@ void *memrchr( const void *s, int c, size_t n );
 size_t strnlen( const char *str, size_t maxlen );
 #endif
 
+void to_upper( char *str, uint len );
+
 int starts_with( const char *str, int strl, const char *cmp, uint cmpl );
 int starts_with_upper( const char *str, int strl, const char *cmp, uint cmpl );
 int equals( const char *str, int strl, const char *cmp, uint cmpl );
diff --git a/src/drv_imap.c b/src/drv_imap.c
index a8c4fd6b..b44df29e 100644
--- a/src/drv_imap.c
+++ b/src/drv_imap.c
@@ -924,7 +924,7 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts )
 				if (sts->level && *s == ')')
 					break;
 			cur->len = (uint)(s - p);
-			if (equals( p, (int)cur->len, "NIL", 3 ))
+			if (equals_upper( p, (int)cur->len, "NIL", 3 ))
 				cur->val = NIL;
 			else
 				cur->val = nfstrndup( p, cur->len );
@@ -1086,12 +1086,13 @@ parse_fetched_flags( list_t *list, uchar *flags, uchar *status )
 		}
 		if (list->val[0] != '\\' && list->val[0] != '$')
 			continue;
-		if (equals( list->val, list->len, "\\Recent", 7 )) {
+		to_upper( list->val, list->len );
+		if (equals( list->val, list->len, "\\RECENT", 7 )) {
 			*status |= M_RECENT;
 			goto flagok;
 		}
 		for (uint i = 0; i < as(Flags); i++) {
-			if (!strcmp( Flags[i], list->val )) {
+			if (!strcasecmp( Flags[i], list->val )) {
 				*flags |= 1 << i;
 				goto flagok;
 			}
@@ -1169,9 +1170,10 @@ parse_fetch_rsp( imap_store_t *ctx, list_t *list )
 			error( "IMAP error: bogus item name in FETCH response\n" );
 			return LIST_BAD;
 		}
-		const char *name = tmp->val;
+		char *name = tmp->val;
 		uint namel = tmp->len;
 		tmp = tmp->next;
+		to_upper( name, namel );
 		if (equals( name, namel, "UID", 3 )) {
 			if (!is_atom( tmp ) || (uid = strtoul( tmp->val, &ep, 10 ), *ep)) {
 				error( "IMAP error: unable to parse UID\n" );
@@ -1282,6 +1284,7 @@ parse_capability( imap_store_t *ctx, char *cmd )
 	ctx->auth_mechs = NULL;
 	ctx->caps = 0x80000000;
 	while ((arg = next_arg( &cmd, &argl ))) {
+		to_upper( arg, argl );
 		if (starts_with( arg, argl, "AUTH=", 5 )) {
 			add_string_list_n( &ctx->auth_mechs, arg + 5, argl - 5 );
 		} else {
@@ -1308,6 +1311,7 @@ parse_response_code( imap_store_t *ctx, imap_cmd_t *cmd, char *s )
 		error( "IMAP error: malformed response code\n" );
 		return RESP_CANCEL;
 	}
+	to_upper( arg, argl );
 	if (equals( arg, argl, "UIDVALIDITY", 11 )) {
 		if (!(arg = next_arg( &s, &argl )) ||
 		    (ctx->uidvalidity = strtoul( arg, &earg, 10 ), *earg != ']'))
@@ -1374,7 +1378,7 @@ parse_response_code( imap_store_t *ctx, imap_cmd_t *cmd, char *s )
 				ret = RESP_CANCEL;
 				break;
 			}
-			if (equals( tmp->val, tmp->len, "\\*", 2 ) || equals( tmp->val, tmp->len, "$Forwarded", 10 )) {
+			if (equals( tmp->val, tmp->len, "\\*", 2 ) || equals_upper( tmp->val, tmp->len, "$FORWARDED", 10 )) {
 				ctx->has_forwarded = 1;
 				break;
 			}
@@ -1621,6 +1625,7 @@ imap_socket_read( void *aux )
 				break;
 			}
 
+			to_upper( arg, argl );
 			if (ctx->greeting == GreetingPending && equals( arg, argl, "PREAUTH", 7 )) {
 				parse_response_code( ctx, NULL, cmd );
 				ctx->greeting = GreetingPreauth;
@@ -1661,6 +1666,7 @@ imap_socket_read( void *aux )
 				resp = parse_list( ctx, cmd, parse_namespace_rsp, "NAMESPACE" );
 				goto listret;
 			} else if ((arg1 = next_arg( &cmd, &argl1 ))) {
+				to_upper( arg1, argl1 );
 				if (equals( arg1, argl1, "EXISTS", 6 )) {
 					ctx->total_msgs = atoi( arg );
 				} else if (equals( arg1, argl1, "EXPUNGE", 7 )) {
@@ -1736,13 +1742,14 @@ imap_socket_read( void *aux )
 				error( "IMAP error: malformed tagged response\n" );
 				break;
 			}
+			to_upper( arg, argl );
 			if (equals( arg, argl, "OK", 2 )) {
 				if (cmdp->param.to_trash)
 					ctx->trashnc = TrashKnown; /* Can't get NO [TRYCREATE] any more. */
 				resp = RESP_OK;
 			} else {
 				if (equals( arg, argl, "NO", 2 )) {
-					if (cmdp->param.create && cmd && starts_with( cmd, -1, "[TRYCREATE]", 11 )) { /* APPEND or UID COPY */
+					if (cmdp->param.create && cmd && starts_with_upper( cmd, -1, "[TRYCREATE]", 11 )) { /* APPEND or UID COPY */
 						imap_cmd_trycreate_t *cmd2 =
 							(imap_cmd_trycreate_t *)new_imap_cmd( sizeof(*cmd2) );
 						cmd2->orig_cmd = cmdp;
diff --git a/src/util.c b/src/util.c
index 162eb2ae..c0203994 100644
--- a/src/util.c
+++ b/src/util.c
@@ -284,6 +284,13 @@ strnlen( const char *str, size_t maxlen )
 
 #endif
 
+void
+to_upper( char *str, uint len )
+{
+	for (uint i = 0; i < len; i++)
+		str[i] = toupper( str[i] );
+}
+
 int
 starts_with( const char *str, int strl, const char *cmp, uint cmpl )
 {