| /*------------------------------------------------------------------------- | |
| * | |
| * sasl.h | |
| * Defines the SASL mechanism interface for the backend. | |
| * | |
| * Each SASL mechanism defines a frontend and a backend callback structure. | |
| * | |
| * See src/interfaces/libpq/fe-auth-sasl.h for the frontend counterpart. | |
| * | |
| * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group | |
| * Portions Copyright (c) 1994, Regents of the University of California | |
| * | |
| * src/include/libpq/sasl.h | |
| * | |
| *------------------------------------------------------------------------- | |
| */ | |
| /* Status codes for message exchange */ | |
| /* | |
| * Backend SASL mechanism callbacks. | |
| * | |
| * To implement a backend mechanism, declare a pg_be_sasl_mech struct with | |
| * appropriate callback implementations. Then pass the mechanism to | |
| * CheckSASLAuth() during ClientAuthentication(), once the server has decided | |
| * which authentication method to use. | |
| */ | |
| typedef struct pg_be_sasl_mech | |
| { | |
| /*--------- | |
| * get_mechanisms() | |
| * | |
| * Retrieves the list of SASL mechanism names supported by this | |
| * implementation. | |
| * | |
| * Input parameters: | |
| * | |
| * port: The client Port | |
| * | |
| * Output parameters: | |
| * | |
| * buf: A StringInfo buffer that the callback should populate with | |
| * supported mechanism names. The names are appended into this | |
| * StringInfo, each one ending with '\0' bytes. | |
| *--------- | |
| */ | |
| void (*get_mechanisms) (Port *port, StringInfo buf); | |
| /*--------- | |
| * init() | |
| * | |
| * Initializes mechanism-specific state for a connection. This callback | |
| * must return a pointer to its allocated state, which will be passed | |
| * as-is as the first argument to the other callbacks. | |
| * | |
| * Input parameters: | |
| * | |
| * port: The client Port. | |
| * | |
| * mech: The actual mechanism name in use by the client. | |
| * | |
| * shadow_pass: The stored secret for the role being authenticated, or | |
| * NULL if one does not exist. Mechanisms that do not use | |
| * shadow entries may ignore this parameter. If a | |
| * mechanism uses shadow entries but shadow_pass is NULL, | |
| * the implementation must continue the exchange as if the | |
| * user existed and the password did not match, to avoid | |
| * disclosing valid user names. | |
| *--------- | |
| */ | |
| void *(*init) (Port *port, const char *mech, const char *shadow_pass); | |
| /*--------- | |
| * exchange() | |
| * | |
| * Produces a server challenge to be sent to the client. The callback | |
| * must return one of the PG_SASL_EXCHANGE_* values, depending on | |
| * whether the exchange continues, has finished successfully, or has | |
| * failed. | |
| * | |
| * Input parameters: | |
| * | |
| * state: The opaque mechanism state returned by init() | |
| * | |
| * input: The response data sent by the client, or NULL if the | |
| * mechanism is client-first but the client did not send an | |
| * initial response. (This can only happen during the first | |
| * message from the client.) This is guaranteed to be | |
| * null-terminated for safety, but SASL allows embedded | |
| * nulls in responses, so mechanisms must be careful to | |
| * check inputlen. | |
| * | |
| * inputlen: The length of the challenge data sent by the server, or | |
| * -1 if the client did not send an initial response | |
| * | |
| * Output parameters, to be set by the callback function: | |
| * | |
| * output: A palloc'd buffer containing either the server's next | |
| * challenge (if PG_SASL_EXCHANGE_CONTINUE is returned) or | |
| * the server's outcome data (if PG_SASL_EXCHANGE_SUCCESS is | |
| * returned and the mechanism requires data to be sent during | |
| * a successful outcome). The callback should set this to | |
| * NULL if the exchange is over and no output should be sent, | |
| * which should correspond to either PG_SASL_EXCHANGE_FAILURE | |
| * or a PG_SASL_EXCHANGE_SUCCESS with no outcome data. | |
| * | |
| * outputlen: The length of the challenge data. Ignored if *output is | |
| * NULL. | |
| * | |
| * logdetail: Set to an optional DETAIL message to be printed to the | |
| * server log, to disambiguate failure modes. (The client | |
| * will only ever see the same generic authentication | |
| * failure message.) Ignored if the exchange is completed | |
| * with PG_SASL_EXCHANGE_SUCCESS. | |
| *--------- | |
| */ | |
| int (*exchange) (void *state, | |
| const char *input, int inputlen, | |
| char **output, int *outputlen, | |
| const char **logdetail); | |
| } pg_be_sasl_mech; | |
| /* Common implementation for auth.c */ | |
| extern int CheckSASLAuth(const pg_be_sasl_mech *mech, Port *port, | |
| char *shadow_pass, const char **logdetail); | |