hs20-osu-client: Explicit checks for snprintf() result

Get rid of the gcc warnings on potentially truncating the output buffer
by explicitly checking that there was enough room to write the full
string.

Signed-off-by: Jouni Malinen <j@w1.fi>

diff --git a/hs20/client/osu_client.c b/hs20/client/osu_client.c
index 7b274dac9d9b9f23295c90a0648cdcaed3845548..01e7b7553ff418dc6edd4db686232e9dc6db2520 100644 (file)
--- a/hs20/client/osu_client.c
+++ b/hs20/client/osu_client.c
@@ -2018,6 +2018,7 @@ static struct osu_data * parse_osu_providers(const char *fname, size_t *count)
        struct osu_data *osu = NULL, *last = NULL;
        size_t osu_count = 0;
        char *pos, *end;
+       int res;
 
        f = fopen(fname, "r");
        if (f == NULL) {
@@ -2037,15 +2038,20 @@ static struct osu_data * parse_osu_providers(const char *fname, size_t *count)
                        osu = last;
                        last = &osu[osu_count++];
                        memset(last, 0, sizeof(*last));
-                       snprintf(last->bssid, sizeof(last->bssid), "%s",
-                                buf + 13);
+                       res = os_snprintf(last->bssid, sizeof(last->bssid),
+                                         "%s", buf + 13);
+                       if (os_snprintf_error(sizeof(last->bssid), res))
+                               break;
                        continue;
                }
                if (!last)
                        continue;
 
                if (strncmp(buf, "uri=", 4) == 0) {
-                       snprintf(last->url, sizeof(last->url), "%s", buf + 4);
+                       res = os_snprintf(last->url, sizeof(last->url),
+                                         "%s", buf + 4);
+                       if (os_snprintf_error(sizeof(last->url), res))
+                               break;
                        continue;
                }
 
@@ -2055,26 +2061,37 @@ static struct osu_data * parse_osu_providers(const char *fname, size_t *count)
                }
 
                if (strncmp(buf, "osu_ssid=", 9) == 0) {
-                       snprintf(last->osu_ssid, sizeof(last->osu_ssid),
-                                "%s", buf + 9);
+                       res = os_snprintf(last->osu_ssid,
+                                         sizeof(last->osu_ssid),
+                                         "%s", buf + 9);
+                       if (os_snprintf_error(sizeof(last->osu_ssid), res))
+                               break;
                        continue;
                }
 
                if (strncmp(buf, "osu_ssid2=", 10) == 0) {
-                       snprintf(last->osu_ssid2, sizeof(last->osu_ssid2),
-                                "%s", buf + 10);
+                       res = os_snprintf(last->osu_ssid2,
+                                         sizeof(last->osu_ssid2),
+                                         "%s", buf + 10);
+                       if (os_snprintf_error(sizeof(last->osu_ssid2), res))
+                               break;
                        continue;
                }
 
                if (os_strncmp(buf, "osu_nai=", 8) == 0) {
-                       os_snprintf(last->osu_nai, sizeof(last->osu_nai),
-                                   "%s", buf + 8);
+                       res = os_snprintf(last->osu_nai, sizeof(last->osu_nai),
+                                         "%s", buf + 8);
+                       if (os_snprintf_error(sizeof(last->osu_nai), res))
+                               break;
                        continue;
                }
 
                if (os_strncmp(buf, "osu_nai2=", 9) == 0) {
-                       os_snprintf(last->osu_nai2, sizeof(last->osu_nai2),
-                                   "%s", buf + 9);
+                       res = os_snprintf(last->osu_nai2,
+                                         sizeof(last->osu_nai2),
+                                         "%s", buf + 9);
+                       if (os_snprintf_error(sizeof(last->osu_nai2), res))
+                               break;
                        continue;
                }
 
@@ -2087,8 +2104,14 @@ static struct osu_data * parse_osu_providers(const char *fname, size_t *count)
                                continue;
                        *pos++ = '\0';
                        txt = &last->friendly_name[last->friendly_name_count++];
-                       snprintf(txt->lang, sizeof(txt->lang), "%s", buf + 14);
-                       snprintf(txt->text, sizeof(txt->text), "%s", pos);
+                       res = os_snprintf(txt->lang, sizeof(txt->lang),
+                                         "%s", buf + 14);
+                       if (os_snprintf_error(sizeof(txt->lang), res))
+                               break;
+                       res = os_snprintf(txt->text, sizeof(txt->text),
+                                         "%s", pos);
+                       if (os_snprintf_error(sizeof(txt->text), res))
+                               break;
                }
 
                if (strncmp(buf, "desc=", 5) == 0) {
@@ -2100,8 +2123,14 @@ static struct osu_data * parse_osu_providers(const char *fname, size_t *count)
                                continue;
                        *pos++ = '\0';
                        txt = &last->serv_desc[last->serv_desc_count++];
-                       snprintf(txt->lang, sizeof(txt->lang), "%s", buf + 5);
-                       snprintf(txt->text, sizeof(txt->text), "%s", pos);
+                       res = os_snprintf(txt->lang, sizeof(txt->lang),
+                                         "%s", buf + 5);
+                       if (os_snprintf_error(sizeof(txt->lang), res))
+                               break;
+                       res = os_snprintf(txt->text, sizeof(txt->text),
+                                         "%s", pos);
+                       if (os_snprintf_error(sizeof(txt->text), res))
+                               break;
                }
 
                if (strncmp(buf, "icon=", 5) == 0) {
@@ -2124,23 +2153,30 @@ static struct osu_data * parse_osu_providers(const char *fname, size_t *count)
                        if (!end)
                                continue;
                        *end = '\0';
-                       snprintf(icon->lang, sizeof(icon->lang), "%s", pos);
+                       res = os_snprintf(icon->lang, sizeof(icon->lang),
+                                         "%s", pos);
+                       if (os_snprintf_error(sizeof(icon->lang), res))
+                               break;
                        pos = end + 1;
 
                        end = strchr(pos, ':');
                        if (end)
                                *end = '\0';
-                       snprintf(icon->mime_type, sizeof(icon->mime_type),
-                                "%s", pos);
-                       if (!pos)
+                       res = os_snprintf(icon->mime_type,
+                                         sizeof(icon->mime_type), "%s", pos);
+                       if (os_snprintf_error(sizeof(icon->mime_type), res))
+                               break;
+                       if (!end)
                                continue;
                        pos = end + 1;
 
                        end = strchr(pos, ':');
                        if (end)
                                *end = '\0';
-                       snprintf(icon->filename, sizeof(icon->filename),
-                                "%s", pos);
+                       res = os_snprintf(icon->filename,
+                                         sizeof(icon->filename), "%s", pos);
+                       if (os_snprintf_error(sizeof(icon->filename), res))
+                               break;
                        continue;
                }
        }