[commit] master: improve error reporting from IMAP list parsing
mailbox synchronizer
Brought to you by:
ossi
Menu
▾
▴
[commit] master: improve error reporting from IMAP list parsing
|
From: Oswald B. <os...@us...> - 2022-06-19 14:38:57
|
commit a07be5f175fbf5586ab54ec5c5bd94b7bf43f417
Author: Oswald Buddenhagen <os...@us...>
Date: Wed Nov 24 22:25:49 2021 +0100
improve error reporting from IMAP list parsing
so far, we'd print only a generic message - except in two cases, where
the generic error would be preceded by a specific one. now we always
print a single reasonably specific message.
src/drv_imap.c | 74 ++++++++++++++++++++++++++++++--------------------
1 file changed, 44 insertions(+), 30 deletions(-)
diff --git a/src/drv_imap.c b/src/drv_imap.c
index 87a1ecc3..51c44279 100644
--- a/src/drv_imap.c
+++ b/src/drv_imap.c
@@ -75,6 +75,7 @@ typedef struct {
list_t *head, **stack[MAX_LIST_DEPTH];
int (*callback)( imap_store_t *ctx, list_t *list );
int level, need_bytes;
+ const char *err;
} parse_list_state_t;
typedef struct imap_cmd imap_cmd_t;
@@ -109,6 +110,7 @@ union imap_store {
uint caps; // CAPABILITY results
string_list_t *auth_mechs;
parse_list_state_t parse_list_sts;
+ const char *parse_list_what;
char *parse_list_cmd;
// Command queue
imap_cmd_t *pending, **pending_append;
@@ -819,8 +821,10 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts )
goto getbytes;
}
- if (!s)
+ if (!s) {
+ sts->err = "missing value";
return LIST_BAD;
+ }
for (;;) {
while (isspace( (uchar)*s ))
s++;
@@ -836,7 +840,7 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts )
if (*s == '(') {
/* sublist */
if (sts->level == MAX_LIST_DEPTH)
- goto bail;
+ goto toodeep;
s++;
cur->val = LIST;
sts->stack[sts->level++] = curp;
@@ -846,11 +850,12 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts )
} else if (ctx && *s == '{') {
/* literal */
bytes = (int)(cur->len = strtoul( s + 1, &s, 10 ));
- if (*s != '}' || *++s)
+ if (*s != '}' || *++s) {
+ sts->err = "malformed literal";
goto bail;
+ }
if ((uint)bytes >= INT_MAX) {
- error( "IMAP error: excessively large literal from %s "
- "- THIS MIGHT BE AN ATTEMPT TO HACK YOU!\n", ctx->conn.name );
+ sts->err = "excessively large literal - THIS MIGHT BE AN ATTEMPT TO HACK YOU!";
goto bail;
}
@@ -861,7 +866,7 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts )
n = socket_read( &ctx->conn, s, (uint)bytes );
if (n < 0) {
badeof:
- error( "IMAP error: unexpected EOF from %s\n", ctx->conn.name );
+ sts->err = "unexpected EOF";
goto bail;
}
bytes -= n;
@@ -891,8 +896,10 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts )
while ((c = *s++) != '"') {
if (c == '\\')
c = *s++;
- if (!c)
+ if (!c) {
+ sts->err = "unterminated quoted string";
goto bail;
+ }
*d++ = c;
}
cur->len = (uint)(d - p);
@@ -914,8 +921,10 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts )
if (!sts->level)
break;
next2:
- if (!*s)
+ if (!*s) {
+ sts->err = "unterminated list";
goto bail;
+ }
}
*sp = s;
return LIST_OK;
@@ -926,6 +935,8 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts )
sts->need_bytes = bytes;
return LIST_PARTIAL;
}
+ toodeep:
+ sts->err = "too deeply nested lists";
bail:
free_list( sts->head );
sts->level = 0;
@@ -937,6 +948,7 @@ parse_list_init( parse_list_state_t *sts )
{
sts->need_bytes = -1;
sts->level = 1;
+ sts->err = NULL;
sts->head = NULL;
sts->stack[0] = &sts->head;
}
@@ -964,12 +976,23 @@ parse_next_list( imap_store_t *ctx, int (*cb)( imap_store_t *ctx, list_t *list )
}
static int
-parse_list( imap_store_t *ctx, char *s, int (*cb)( imap_store_t *ctx, list_t *list ) )
+parse_list( imap_store_t *ctx, char *s, int (*cb)( imap_store_t *ctx, list_t *list ), const char *what )
{
ctx->parse_list_cmd = s;
+ ctx->parse_list_what = what;
return parse_next_list( ctx, cb );
}
+static int
+parse_list_perror( imap_store_t *ctx )
+{
+ if (!ctx->parse_list_sts.err)
+ ctx->parse_list_sts.err = "unexpected value";
+ error( "IMAP error: malformed %s response from %s: %s\n",
+ ctx->parse_list_what, ctx->conn.name, ctx->parse_list_sts.err );
+ return LIST_BAD;
+}
+
static int parse_namespace_rsp_p2( imap_store_t *, list_t * );
static int parse_namespace_rsp_p3( imap_store_t *, list_t * );
@@ -981,8 +1004,7 @@ parse_namespace_rsp( imap_store_t *ctx, list_t *list )
if (!list) {
bad:
- error( "IMAP error: malformed NAMESPACE response\n" );
- return LIST_BAD;
+ return parse_list_perror( ctx );
}
if (list->val != NIL) {
if (list->val != LIST)
@@ -1121,10 +1143,8 @@ parse_fetch_rsp( imap_store_t *ctx, list_t *list )
uint uid = 0, size = 0, msgid_len = 0;
time_t date = 0;
- if (!is_list( list )) {
- error( "IMAP error: bogus FETCH response\n" );
- return LIST_BAD;
- }
+ if (!is_list( list ))
+ return parse_list_perror( ctx );
for (tmp = list->child; tmp; tmp = tmp->next) {
if (!is_atom( tmp )) {
@@ -1354,10 +1374,8 @@ parse_list_rsp( imap_store_t *ctx, list_t *list )
{
list_t *lp;
- if (!is_list( list )) {
- error( "IMAP error: malformed LIST response\n" );
- return LIST_BAD;
- }
+ if (!is_list( list ))
+ return parse_list_perror( ctx );
for (lp = list->child; lp; lp = lp->next)
if (is_atom( lp ) && !strcasecmp( lp->val, "\\NoSelect" ))
return LIST_OK;
@@ -1367,10 +1385,8 @@ parse_list_rsp( imap_store_t *ctx, list_t *list )
static int
parse_list_rsp_p1( imap_store_t *ctx, list_t *list )
{
- if (!is_opt_atom( list )) {
- error( "IMAP error: malformed LIST response\n" );
- return LIST_BAD;
- }
+ if (!is_opt_atom( list ))
+ return parse_list_perror( ctx );
if (!ctx->delimiter[0] && is_atom( list ))
ctx->delimiter[0] = list->val[0];
return parse_next_list( ctx, parse_list_rsp_p2 );
@@ -1413,10 +1429,8 @@ parse_list_rsp_p2( imap_store_t *ctx, list_t *list )
int argl;
uint l;
- if (!is_atom( list )) {
- error( "IMAP error: malformed LIST response\n" );
- return LIST_BAD;
- }
+ if (!is_atom( list ))
+ return parse_list_perror( ctx );
arg = list->val;
argl = (int)list->len;
if (argl > 1000) {
@@ -1623,10 +1637,10 @@ imap_socket_read( void *aux )
} else if (!strcmp( "CAPABILITY", arg )) {
parse_capability( ctx, cmd );
} else if (!strcmp( "LIST", arg ) || !strcmp( "LSUB", arg )) {
- resp = parse_list( ctx, cmd, parse_list_rsp );
+ resp = parse_list( ctx, cmd, parse_list_rsp, "LIST" );
goto listret;
} else if (!strcmp( "NAMESPACE", arg )) {
- resp = parse_list( ctx, cmd, parse_namespace_rsp );
+ resp = parse_list( ctx, cmd, parse_namespace_rsp, "NAMESPACE" );
goto listret;
} else if ((arg1 = next_arg( &cmd ))) {
if (!strcmp( "EXISTS", arg1 )) {
@@ -1645,7 +1659,7 @@ imap_socket_read( void *aux )
if (!(seq = strtoul( arg, &arg1, 10 )) || *arg1)
goto badseq;
ctx->fetch_seq = seq;
- resp = parse_list( ctx, cmd, parse_fetch_rsp );
+ resp = parse_list( ctx, cmd, parse_fetch_rsp, "FETCH" );
goto listret;
}
} else {
|
