Views: apply user SSH public key override

With this patch the SSH public key override attribute is read from the
FreeIPA server and saved in the cache with the other override data.

Since it is possible to have multiple public SSH keys this override
value does not replace any other data but will be added to existing
values.

Fixes https://fedorahosted.org/sssd/ticket/2454

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>

1 files changed, 94 insertions, 29 deletions

diff --git a/src/responder/ssh/sshsrv_cmd.c b/src/responder/ssh/sshsrv_cmd.c
index ad8316398..5bed2e0ad 100644
--- a/src/responder/ssh/sshsrv_cmd.c
+++ b/src/responder/ssh/sshsrv_cmd.c
@@ -232,8 +232,8 @@ ssh_user_pubkeys_search_next(struct ssh_cmd_ctx *cmd_ctx)
         return EFAULT;
     }
 
-    ret = sysdb_get_user_attr(cmd_ctx, cmd_ctx->domain,
-                              cmd_ctx->name, attrs, &res);
+    ret = sysdb_get_user_attr_with_views(cmd_ctx, cmd_ctx->domain,
+                                         cmd_ctx->name, attrs, &res);
     if (ret != EOK) {
         DEBUG(SSSDBG_CRIT_FAILURE,
               "Failed to make request to our cache!\n");
@@ -782,6 +782,65 @@ ssh_cmd_parse_request(struct ssh_cmd_ctx *cmd_ctx)
     return EOK;
 }
 
+static errno_t decode_and_add_base64_data(struct ssh_cmd_ctx *cmd_ctx,
+                                          struct ldb_message_element *el,
+                                          size_t fqname_len,
+                                          const char *fqname,
+                                          size_t *c)
+{
+    struct cli_ctx *cctx = cmd_ctx->cctx;
+    uint8_t *key;
+    size_t key_len;
+    uint8_t *body;
+    size_t body_len;
+    int ret;
+    size_t d;
+    TALLOC_CTX *tmp_ctx;
+
+    if (el == NULL) {
+        DEBUG(SSSDBG_TRACE_ALL, "Mssing element, nothing to do.\n");
+        return EOK;
+    }
+
+    tmp_ctx = talloc_new(NULL);
+    if (tmp_ctx == NULL) {
+        DEBUG(SSSDBG_OP_FAILURE, "talloc_new failed.\n");
+        return ENOMEM;
+    }
+
+    for (d = 0; d < el->num_values; d++) {
+        key = sss_base64_decode(tmp_ctx, (const char *) el->values[d].data,
+                                &key_len);
+        if (key == NULL) {
+            DEBUG(SSSDBG_OP_FAILURE, "sss_base64_decode failed.\n");
+            ret = ENOMEM;
+            goto done;
+        }
+
+        ret = sss_packet_grow(cctx->creq->out,
+                              3*sizeof(uint32_t) + key_len + fqname_len);
+        if (ret != EOK) {
+            DEBUG(SSSDBG_OP_FAILURE, "sss_packet_grow failed.\n");
+            goto done;
+        }
+        sss_packet_get_body(cctx->creq->out, &body, &body_len);
+
+        SAFEALIGN_SET_UINT32(body+(*c), 0, c);
+        SAFEALIGN_SET_UINT32(body+(*c), fqname_len, c);
+        safealign_memcpy(body+(*c), fqname, fqname_len, c);
+        SAFEALIGN_SET_UINT32(body+(*c), key_len, c);
+        safealign_memcpy(body+(*c), key, key_len, c);
+
+    }
+
+    ret = EOK;
+
+done:
+    talloc_free(tmp_ctx);
+
+    return ret;
+}
+
 static errno_t
 ssh_cmd_build_reply(struct ssh_cmd_ctx *cmd_ctx)
 {
@@ -790,14 +849,13 @@ ssh_cmd_build_reply(struct ssh_cmd_ctx *cmd_ctx)
     uint8_t *body;
     size_t body_len;
     size_t c = 0;
-    unsigned int i;
-    struct ldb_message_element *el;
+    struct ldb_message_element *el = NULL;
+    struct ldb_message_element *el_override = NULL;
+    struct ldb_message_element *el_orig = NULL;
     uint32_t count = 0;
     const char *name;
     char *fqname;
     uint32_t fqname_len;
-    uint8_t *key;
-    size_t key_len;
 
     ret = sss_packet_new(cctx->creq, 0,
                          sss_packet_get_cmd(cctx->creq->in),
@@ -811,6 +869,20 @@ ssh_cmd_build_reply(struct ssh_cmd_ctx *cmd_ctx)
         count = el->num_values;
     }
 
+    el_orig = ldb_msg_find_element(cmd_ctx->result,
+                                  ORIGINALAD_PREFIX SYSDB_SSH_PUBKEY);
+    if (el_orig) {
+        count = el_orig->num_values;
+    }
+
+    if (DOM_HAS_VIEWS(cmd_ctx->domain)) {
+        el_override = ldb_msg_find_element(cmd_ctx->result,
+                                           OVERRIDE_PREFIX SYSDB_SSH_PUBKEY);
+        if (el_override) {
+            count += el_override->num_values;
+        }
+    }
+
     ret = sss_packet_grow(cctx->creq->out, 2*sizeof(uint32_t));
     if (ret != EOK) {
         return ret;
@@ -820,7 +892,7 @@ ssh_cmd_build_reply(struct ssh_cmd_ctx *cmd_ctx)
     SAFEALIGN_SET_UINT32(body+c, count, &c);
     SAFEALIGN_SET_UINT32(body+c, 0, &c);
 
-    if (!el) {
+    if (count == 0) {
         return EOK;
     }
 
@@ -840,30 +912,23 @@ ssh_cmd_build_reply(struct ssh_cmd_ctx *cmd_ctx)
 
     fqname_len = strlen(fqname)+1;
 
-    for (i = 0; i < el->num_values; i++) {
-        key = sss_base64_decode(cmd_ctx,
-                                (const char *)el->values[i].data,
-                                &key_len);
-        if (!key) {
-            return ENOMEM;
-        }
-
-        ret = sss_packet_grow(cctx->creq->out,
-                              3*sizeof(uint32_t) + key_len + fqname_len);
-        if (ret != EOK) {
-            talloc_free(key);
-            return ret;
-        }
-        sss_packet_get_body(cctx->creq->out, &body, &body_len);
+    ret = decode_and_add_base64_data(cmd_ctx, el, fqname_len, fqname, &c);
+    if (ret != EOK) {
+        DEBUG(SSSDBG_OP_FAILURE, "decode_and_add_base64_data failed.\n");
+        return ret;
+    }
 
-        SAFEALIGN_SET_UINT32(body+c, 0, &c);
-        SAFEALIGN_SET_UINT32(body+c, fqname_len, &c);
-        safealign_memcpy(body+c, fqname, fqname_len, &c);
-        SAFEALIGN_SET_UINT32(body+c, key_len, &c);
-        safealign_memcpy(body+c, key, key_len, &c);
+    ret = decode_and_add_base64_data(cmd_ctx, el_orig, fqname_len, fqname, &c);
+    if (ret != EOK) {
+        DEBUG(SSSDBG_OP_FAILURE, "decode_and_add_base64_data failed.\n");
+        return ret;
+    }
 
-        talloc_free(key);
-        count++;
+    ret = decode_and_add_base64_data(cmd_ctx, el_override, fqname_len, fqname,
+                                     &c);
+    if (ret != EOK) {
+        DEBUG(SSSDBG_OP_FAILURE, "decode_and_add_base64_data failed.\n");
+        return ret;
     }
 
     return EOK;